Merge tag 'tty-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver update from Greg Kroah-Hartman:
"Here's the big tty/serial driver merge request for 3.10-rc1

Once again, Jiri has a number of TTY driver fixes and cleanups, and
Peter Hurley came through with a bunch of ldisc fixes that resolve a
number of reported issues. There are some other serial driver
cleanups as well.

All of these have been in the linux-next tree for a while"

* tag 'tty-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (117 commits)
tty/serial/sirf: fix MODULE_DEVICE_TABLE
serial: mxs: drop superfluous {get|put}_device
serial: mxs: fix buffer overflow
ARM: PL011: add support for extended FIFO-size of PL011-r1p5
serial_core.c: add put_device() after device_find_child()
tty: Fix unsafe bit ops in tty_throttle_safe/unthrottle_safe
serial: sccnxp: Replace pdata.init/exit with regulator API
serial: sccnxp: Do not override device name
TTY: pty, fix compilation warning
TTY: rocket, fix compilation warning
TTY: ircomm: fix DTR being raised on hang up
TTY: synclinkmp: fix DTR being raised on hang up
TTY: synclink_gt: fix DTR being raised on hang up
TTY: synclink: fix DTR being raised on hang up
serial: 8250_dw: Fix the stub for dw8250_probe_acpi()
serial: 8250_dw: Convert to devm_ioremap()
serial: 8250_dw: Set port capabilities based on CPR register
serial: 8250_dw: Let ACPI code extract the DMA client info
serial: 8250_dw: Support clk framework also with ACPI
serial: 8250_dw: Enable runtime PM
...

Documentation/devicetree/bindings/tty/serial/of-serial.txt

···
   RTAS and should not be registered.
 - no-loopback-test: set to indicate that the port does not implements loopback
   test mode
+- fifo-size: the fifo size of the UART.
+- auto-flow-control: one way to enable automatic flow control support. The
+  driver is allowed to detect support for the capability even without this
+  property.
 
 Example:
 

arch/arm/mach-s3c24xx/clock-s3c2440.c

···
 	.ctrlbit	= S3C2440_CLKCON_AC97,
 };
 
+#define S3C24XX_VA_UART0      (S3C_VA_UART)
+#define S3C24XX_VA_UART1      (S3C_VA_UART + 0x4000 )
+#define S3C24XX_VA_UART2      (S3C_VA_UART + 0x8000 )
+#define S3C24XX_VA_UART3      (S3C_VA_UART + 0xC000 )
+
 static unsigned long  s3c2440_fclk_n_getrate(struct clk *clk)
 {
 	unsigned long ucon0, ucon1, ucon2, divisor;

arch/arm/mach-s3c24xx/common.c

···
 
 /* Serial port registrations */
 
+#define S3C2410_PA_UART0      (S3C24XX_PA_UART)
+#define S3C2410_PA_UART1      (S3C24XX_PA_UART + 0x4000 )
+#define S3C2410_PA_UART2      (S3C24XX_PA_UART + 0x8000 )
+#define S3C2443_PA_UART3      (S3C24XX_PA_UART + 0xC000 )
+
 static struct resource s3c2410_uart0_resource[] = {
 	[0] = DEFINE_RES_MEM(S3C2410_PA_UART0, SZ_16K),
 	[1] = DEFINE_RES_NAMED(IRQ_S3CUART_RX0, \

arch/arm/plat-samsung/include/plat/regs-serial.h

···
-/* arch/arm/plat-samsung/include/plat/regs-serial.h
- *
- *  From linux/include/asm-arm/hardware/serial_s3c2410.h
- *
- *  Internal header file for Samsung S3C2410 serial ports (UART0-2)
- *
- *  Copyright (C) 2002 Shane Nay ([e-mail])
- *
- *  Additional defines, Copyright 2003 Simtec Electronics ([e-mail])
- *
- *  Adapted from:
- *
- *  Internal header file for MX1ADS serial ports (UART1 & 2)
- *
- *  Copyright (C) 2002 Shane Nay ([e-mail])
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-*/
-
-#ifndef __ASM_ARM_REGS_SERIAL_H
-#define __ASM_ARM_REGS_SERIAL_H
-
-#define S3C24XX_VA_UART0      (S3C_VA_UART)
-#define S3C24XX_VA_UART1      (S3C_VA_UART + 0x4000 )
-#define S3C24XX_VA_UART2      (S3C_VA_UART + 0x8000 )
-#define S3C24XX_VA_UART3      (S3C_VA_UART + 0xC000 )
-
-#define S3C2410_PA_UART0      (S3C24XX_PA_UART)
-#define S3C2410_PA_UART1      (S3C24XX_PA_UART + 0x4000 )
-#define S3C2410_PA_UART2      (S3C24XX_PA_UART + 0x8000 )
-#define S3C2443_PA_UART3      (S3C24XX_PA_UART + 0xC000 )
-
-#define S3C2410_URXH	  (0x24)
-#define S3C2410_UTXH	  (0x20)
-#define S3C2410_ULCON	  (0x00)
-#define S3C2410_UCON	  (0x04)
-#define S3C2410_UFCON	  (0x08)
-#define S3C2410_UMCON	  (0x0C)
-#define S3C2410_UBRDIV	  (0x28)
-#define S3C2410_UTRSTAT	  (0x10)
-#define S3C2410_UERSTAT	  (0x14)
-#define S3C2410_UFSTAT	  (0x18)
-#define S3C2410_UMSTAT	  (0x1C)
-
-#define S3C2410_LCON_CFGMASK	  ((0xF<<3)|(0x3))
-
-#define S3C2410_LCON_CS5	  (0x0)
-#define S3C2410_LCON_CS6	  (0x1)
-#define S3C2410_LCON_CS7	  (0x2)
-#define S3C2410_LCON_CS8	  (0x3)
-#define S3C2410_LCON_CSMASK	  (0x3)
-
-#define S3C2410_LCON_PNONE	  (0x0)
-#define S3C2410_LCON_PEVEN	  (0x5 << 3)
-#define S3C2410_LCON_PODD	  (0x4 << 3)
-#define S3C2410_LCON_PMASK	  (0x7 << 3)
-
-#define S3C2410_LCON_STOPB	  (1<<2)
-#define S3C2410_LCON_IRM          (1<<6)
-
-#define S3C2440_UCON_CLKMASK	  (3<<10)
-#define S3C2440_UCON_CLKSHIFT	  (10)
-#define S3C2440_UCON_PCLK	  (0<<10)
-#define S3C2440_UCON_UCLK	  (1<<10)
-#define S3C2440_UCON_PCLK2	  (2<<10)
-#define S3C2440_UCON_FCLK	  (3<<10)
-#define S3C2443_UCON_EPLL	  (3<<10)
-
-#define S3C6400_UCON_CLKMASK	(3<<10)
-#define S3C6400_UCON_CLKSHIFT	(10)
-#define S3C6400_UCON_PCLK	(0<<10)
-#define S3C6400_UCON_PCLK2	(2<<10)
-#define S3C6400_UCON_UCLK0	(1<<10)
-#define S3C6400_UCON_UCLK1	(3<<10)
-
-#define S3C2440_UCON2_FCLK_EN	  (1<<15)
-#define S3C2440_UCON0_DIVMASK	  (15 << 12)
-#define S3C2440_UCON1_DIVMASK	  (15 << 12)
-#define S3C2440_UCON2_DIVMASK	  (7 << 12)
-#define S3C2440_UCON_DIVSHIFT	  (12)
-
-#define S3C2412_UCON_CLKMASK	(3<<10)
-#define S3C2412_UCON_CLKSHIFT	(10)
-#define S3C2412_UCON_UCLK	(1<<10)
-#define S3C2412_UCON_USYSCLK	(3<<10)
-#define S3C2412_UCON_PCLK	(0<<10)
-#define S3C2412_UCON_PCLK2	(2<<10)
-
-#define S3C2410_UCON_CLKMASK	(1 << 10)
-#define S3C2410_UCON_CLKSHIFT	(10)
-#define S3C2410_UCON_UCLK	  (1<<10)
-#define S3C2410_UCON_SBREAK	  (1<<4)
-
-#define S3C2410_UCON_TXILEVEL	  (1<<9)
-#define S3C2410_UCON_RXILEVEL	  (1<<8)
-#define S3C2410_UCON_TXIRQMODE	  (1<<2)
-#define S3C2410_UCON_RXIRQMODE	  (1<<0)
-#define S3C2410_UCON_RXFIFO_TOI	  (1<<7)
-#define S3C2443_UCON_RXERR_IRQEN  (1<<6)
-#define S3C2443_UCON_LOOPBACK	  (1<<5)
-
-#define S3C2410_UCON_DEFAULT	  (S3C2410_UCON_TXILEVEL  | \
-				   S3C2410_UCON_RXILEVEL  | \
-				   S3C2410_UCON_TXIRQMODE | \
-				   S3C2410_UCON_RXIRQMODE | \
-				   S3C2410_UCON_RXFIFO_TOI)
-
-#define S3C2410_UFCON_FIFOMODE	  (1<<0)
-#define S3C2410_UFCON_TXTRIG0	  (0<<6)
-#define S3C2410_UFCON_RXTRIG8	  (1<<4)
-#define S3C2410_UFCON_RXTRIG12	  (2<<4)
-
-/* S3C2440 FIFO trigger levels */
-#define S3C2440_UFCON_RXTRIG1	  (0<<4)
-#define S3C2440_UFCON_RXTRIG8	  (1<<4)
-#define S3C2440_UFCON_RXTRIG16	  (2<<4)
-#define S3C2440_UFCON_RXTRIG32	  (3<<4)
-
-#define S3C2440_UFCON_TXTRIG0	  (0<<6)
-#define S3C2440_UFCON_TXTRIG16	  (1<<6)
-#define S3C2440_UFCON_TXTRIG32	  (2<<6)
-#define S3C2440_UFCON_TXTRIG48	  (3<<6)
-
-#define S3C2410_UFCON_RESETBOTH	  (3<<1)
-#define S3C2410_UFCON_RESETTX	  (1<<2)
-#define S3C2410_UFCON_RESETRX	  (1<<1)
-
-#define S3C2410_UFCON_DEFAULT	  (S3C2410_UFCON_FIFOMODE | \
-				   S3C2410_UFCON_TXTRIG0  | \
-				   S3C2410_UFCON_RXTRIG8 )
-
-#define	S3C2410_UMCOM_AFC	  (1<<4)
-#define	S3C2410_UMCOM_RTS_LOW	  (1<<0)
-
-#define S3C2412_UMCON_AFC_63	(0<<5)		/* same as s3c2443 */
-#define S3C2412_UMCON_AFC_56	(1<<5)
-#define S3C2412_UMCON_AFC_48	(2<<5)
-#define S3C2412_UMCON_AFC_40	(3<<5)
-#define S3C2412_UMCON_AFC_32	(4<<5)
-#define S3C2412_UMCON_AFC_24	(5<<5)
-#define S3C2412_UMCON_AFC_16	(6<<5)
-#define S3C2412_UMCON_AFC_8	(7<<5)
-
-#define S3C2410_UFSTAT_TXFULL	  (1<<9)
-#define S3C2410_UFSTAT_RXFULL	  (1<<8)
-#define S3C2410_UFSTAT_TXMASK	  (15<<4)
-#define S3C2410_UFSTAT_TXSHIFT	  (4)
-#define S3C2410_UFSTAT_RXMASK	  (15<<0)
-#define S3C2410_UFSTAT_RXSHIFT	  (0)
-
-/* UFSTAT S3C2443 same as S3C2440 */
-#define S3C2440_UFSTAT_TXFULL	  (1<<14)
-#define S3C2440_UFSTAT_RXFULL	  (1<<6)
-#define S3C2440_UFSTAT_TXSHIFT	  (8)
-#define S3C2440_UFSTAT_RXSHIFT	  (0)
-#define S3C2440_UFSTAT_TXMASK	  (63<<8)
-#define S3C2440_UFSTAT_RXMASK	  (63)
-
-#define S3C2410_UTRSTAT_TXE	  (1<<2)
-#define S3C2410_UTRSTAT_TXFE	  (1<<1)
-#define S3C2410_UTRSTAT_RXDR	  (1<<0)
-
-#define S3C2410_UERSTAT_OVERRUN	  (1<<0)
-#define S3C2410_UERSTAT_FRAME	  (1<<2)
-#define S3C2410_UERSTAT_BREAK	  (1<<3)
-#define S3C2443_UERSTAT_PARITY	  (1<<1)
-
-#define S3C2410_UERSTAT_ANY	  (S3C2410_UERSTAT_OVERRUN | \
-				   S3C2410_UERSTAT_FRAME | \
-				   S3C2410_UERSTAT_BREAK)
-
-#define S3C2410_UMSTAT_CTS	  (1<<0)
-#define S3C2410_UMSTAT_DeltaCTS	  (1<<2)
-
-#define S3C2443_DIVSLOT		  (0x2C)
-
-/* S3C64XX interrupt registers. */
-#define S3C64XX_UINTP		0x30
-#define S3C64XX_UINTSP		0x34
-#define S3C64XX_UINTM		0x38
-
-#define S3C64XX_UINTM_RXD	(0)
-#define S3C64XX_UINTM_TXD	(2)
-#define S3C64XX_UINTM_RXD_MSK	(1 << S3C64XX_UINTM_RXD)
-#define S3C64XX_UINTM_TXD_MSK	(1 << S3C64XX_UINTM_TXD)
-
-/* Following are specific to S5PV210 */
-#define S5PV210_UCON_CLKMASK	(1<<10)
-#define S5PV210_UCON_CLKSHIFT	(10)
-#define S5PV210_UCON_PCLK	(0<<10)
-#define S5PV210_UCON_UCLK	(1<<10)
-
-#define S5PV210_UFCON_TXTRIG0	(0<<8)
-#define S5PV210_UFCON_TXTRIG4	(1<<8)
-#define S5PV210_UFCON_TXTRIG8	(2<<8)
-#define S5PV210_UFCON_TXTRIG16	(3<<8)
-#define S5PV210_UFCON_TXTRIG32	(4<<8)
-#define S5PV210_UFCON_TXTRIG64	(5<<8)
-#define S5PV210_UFCON_TXTRIG128 (6<<8)
-#define S5PV210_UFCON_TXTRIG256 (7<<8)
-
-#define S5PV210_UFCON_RXTRIG1	(0<<4)
-#define S5PV210_UFCON_RXTRIG4	(1<<4)
-#define S5PV210_UFCON_RXTRIG8	(2<<4)
-#define S5PV210_UFCON_RXTRIG16	(3<<4)
-#define S5PV210_UFCON_RXTRIG32	(4<<4)
-#define S5PV210_UFCON_RXTRIG64	(5<<4)
-#define S5PV210_UFCON_RXTRIG128	(6<<4)
-#define S5PV210_UFCON_RXTRIG256	(7<<4)
-
-#define S5PV210_UFSTAT_TXFULL	(1<<24)
-#define S5PV210_UFSTAT_RXFULL	(1<<8)
-#define S5PV210_UFSTAT_TXMASK	(255<<16)
-#define S5PV210_UFSTAT_TXSHIFT	(16)
-#define S5PV210_UFSTAT_RXMASK	(255<<0)
-#define S5PV210_UFSTAT_RXSHIFT	(0)
-
-#define S3C2410_UCON_CLKSEL0	(1 << 0)
-#define S3C2410_UCON_CLKSEL1	(1 << 1)
-#define S3C2410_UCON_CLKSEL2	(1 << 2)
-#define S3C2410_UCON_CLKSEL3	(1 << 3)
-
-/* Default values for s5pv210 UCON and UFCON uart registers */
-#define S5PV210_UCON_DEFAULT	(S3C2410_UCON_TXILEVEL |	\
-				 S3C2410_UCON_RXILEVEL |	\
-				 S3C2410_UCON_TXIRQMODE |	\
-				 S3C2410_UCON_RXIRQMODE |	\
-				 S3C2410_UCON_RXFIFO_TOI |	\
-				 S3C2443_UCON_RXERR_IRQEN)
-
-#define S5PV210_UFCON_DEFAULT	(S3C2410_UFCON_FIFOMODE |	\
-				 S5PV210_UFCON_TXTRIG4 |	\
-				 S5PV210_UFCON_RXTRIG4)
-
-#ifndef __ASSEMBLY__
-
-/* configuration structure for per-machine configurations for the
- * serial port
- *
- * the pointer is setup by the machine specific initialisation from the
- * arch/arm/mach-s3c2410/ directory.
-*/
-
-struct s3c2410_uartcfg {
-	unsigned char	   hwport;	 /* hardware port number */
-	unsigned char	   unused;
-	unsigned short	   flags;
-	upf_t		   uart_flags;	 /* default uart flags */
-	unsigned int	   clk_sel;
-
-	unsigned int	   has_fracval;
-
-	unsigned long	   ucon;	 /* value of ucon for port */
-	unsigned long	   ulcon;	 /* value of ulcon for port */
-	unsigned long	   ufcon;	 /* value of ufcon for port */
-};
-
-/* s3c24xx_uart_devs
- *
- * this is exported from the core as we cannot use driver_register(),
- * or platform_add_device() before the console_initcall()
-*/
-
-extern struct platform_device *s3c24xx_uart_devs[4];
-
-#endif /* __ASSEMBLY__ */
-
-#endif /* __ASM_ARM_REGS_SERIAL_H */
-
+#include <linux/serial_s3c.h>

arch/ia64/hp/sim/simserial.c

···
 		goto out;
 	}
 
-	if (info->xmit.head == info->xmit.tail || tty->stopped ||
-			tty->hw_stopped) {
+	if (info->xmit.head == info->xmit.tail || tty->stopped) {
 #ifdef SIMSERIAL_DEBUG
 		printk("transmit_chars: head=%d, tail=%d, stopped=%d\n",
 		       info->xmit.head, info->xmit.tail, tty->stopped);
···
 	struct serial_state *info = tty->driver_data;
 
 	if (info->xmit.head == info->xmit.tail || tty->stopped ||
-			tty->hw_stopped || !info->xmit.buf)
+			!info->xmit.buf)
 		return;
 
 	transmit_chars(tty, info, NULL);
···
 	 * Hey, we transmit directly from here in our case
 	 */
 	if (CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE) &&
-			!tty->stopped && !tty->hw_stopped)
+			!tty->stopped)
 		transmit_chars(tty, info, NULL);
 
 	return ret;
···
 
 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
 
-static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
-{
-	/* Handle turning off CRTSCTS */
-	if ((old_termios->c_cflag & CRTSCTS) &&
-	    !(tty->termios.c_cflag & CRTSCTS)) {
-		tty->hw_stopped = 0;
-	}
-}
 /*
  * This routine will shutdown a serial port; interrupts are disabled, and
  * DTR is dropped if the hangup on close termio flag is on.
···
 	.throttle = rs_throttle,
 	.unthrottle = rs_unthrottle,
 	.send_xchar = rs_send_xchar,
-	.set_termios = rs_set_termios,
 	.hangup = rs_hangup,
 	.proc_fops = &rs_proc_fops,
 };

arch/um/drivers/chan_kern.c

···
 		reactivate_fd(chan->fd, irq);
 	if (err == -EIO) {
 		if (chan->primary) {
-			struct tty_struct *tty = tty_port_tty_get(&line->port);
-			if (tty != NULL) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			tty_port_tty_hangup(&line->port, false);
 			if (line->chan_out != chan)
 				close_one_chan(line->chan_out, 1);
 		}

arch/um/drivers/line.c

···
 {
 	struct chan *chan = data;
 	struct line *line = chan->line;
-	struct tty_struct *tty;
 	int err;
 
 	/*
···
 	}
 	spin_unlock(&line->lock);
 
-	tty = tty_port_tty_get(&line->port);
-	if (tty == NULL)
-		return IRQ_NONE;
-
-	tty_wakeup(tty);
-	tty_kref_put(tty);
+	tty_port_tty_wakeup(&line->port);
 
 	return IRQ_HANDLED;
 }

drivers/isdn/capi/capi.c

···
 {
 	struct capidev *cdev = ap->private;
 #ifdef CONFIG_ISDN_CAPI_MIDDLEWARE
-	struct tty_struct *tty;
 	struct capiminor *mp;
 	u16 datahandle;
 	struct capincci *np;
···
 			 CAPIMSG_U16(skb->data, CAPIMSG_BASELEN + 4 + 2));
 		kfree_skb(skb);
 		capiminor_del_ack(mp, datahandle);
-		tty = tty_port_tty_get(&mp->port);
-		if (tty) {
-			tty_wakeup(tty);
-			tty_kref_put(tty);
-		}
+		tty_port_tty_wakeup(&mp->port);
 		handle_minor_send(mp);
 
 	} else {

drivers/isdn/gigaset/interface.c

···
 static void if_wake(unsigned long data)
 {
 	struct cardstate *cs = (struct cardstate *)data;
-	struct tty_struct *tty = tty_port_tty_get(&cs->port);
 
-	if (tty) {
-		tty_wakeup(tty);
-		tty_kref_put(tty);
-	}
+	tty_port_tty_wakeup(&cs->port);
 }
 
 /*** interface to common ***/

drivers/isdn/i4l/isdn_tty.c

···
 		    tty->termios.c_ospeed == old_termios->c_ospeed)
 			return;
 		isdn_tty_change_speed(info);
-		if ((old_termios->c_cflag & CRTSCTS) &&
-		    !(tty->termios.c_cflag & CRTSCTS))
-			tty->hw_stopped = 0;
 	}
 }
 

drivers/mmc/card/sdio_uart.c

···
 static void sdio_uart_port_remove(struct sdio_uart_port *port)
 {
 	struct sdio_func *func;
-	struct tty_struct *tty;
 
 	BUG_ON(sdio_uart_table[port->index] != port);
 
···
 	sdio_claim_host(func);
 	port->func = NULL;
 	mutex_unlock(&port->func_lock);
-	tty = tty_port_tty_get(&port->port);
 	/* tty_hangup is async so is this safe as is ?? */
-	if (tty) {
-		tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	tty_port_tty_hangup(&port->port, false);
 	mutex_unlock(&port->port.mutex);
 	sdio_release_irq(func);
 	sdio_disable_func(func);
···
 			wake_up_interruptible(&port->port.open_wait);
 		else {
 			/* DCD drop - hang up if tty attached */
-			tty = tty_port_tty_get(&port->port);
-			if (tty) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			tty_port_tty_hangup(&port->port, false);
 		}
 	}
 	if (status & UART_MSR_DCTS) {

drivers/net/caif/caif_serial.c

···
 {
 	ser->tty_status =
 		ser->tty->stopped << 5 |
-		ser->tty->hw_stopped << 4 |
 		ser->tty->flow_stopped << 3 |
 		ser->tty->packet << 2 |
-		ser->tty->port->low_latency << 1 |
-		ser->tty->warned;
+		ser->tty->port->low_latency << 1;
 }
 static inline void debugfs_init(struct ser_device *ser, struct tty_struct *tty)
 {

drivers/net/ppp/ppp_async.c

···
 		/* flush our buffers and the serial port's buffer */
 		if (arg == TCIOFLUSH || arg == TCOFLUSH)
 			ppp_async_flush_output(ap);
-		err = tty_perform_flush(tty, arg);
+		err = n_tty_ioctl_helper(tty, file, cmd, arg);
 		break;
 
 	case FIONREAD:

drivers/net/ppp/ppp_synctty.c

···
 		/* flush our buffers and the serial port's buffer */
 		if (arg == TCIOFLUSH || arg == TCOFLUSH)
 			ppp_sync_flush_output(ap);
-		err = tty_perform_flush(tty, arg);
+		err = n_tty_ioctl_helper(tty, file, cmd, arg);
 		break;
 
 	case FIONREAD:

drivers/net/usb/hso.c

···
 {
 	struct hso_serial *serial = urb->context;
 	int status = urb->status;
-	struct tty_struct *tty;
 
 	/* sanity check */
 	if (!serial) {
···
 		return;
 	}
 	hso_put_activity(serial->parent);
-	tty = tty_port_tty_get(&serial->port);
-	if (tty) {
-		tty_wakeup(tty);
-		tty_kref_put(tty);
-	}
+	tty_port_tty_wakeup(&serial->port);
 	hso_kick_transmit(serial);
 
 	D1(" ");
···
 		put_rxbuf_data_and_resubmit_ctrl_urb(serial);
 		spin_unlock(&serial->serial_lock);
 	} else {
-		struct tty_struct *tty = tty_port_tty_get(&serial->port);
 		hso_put_activity(serial->parent);
-		if (tty) {
-			tty_wakeup(tty);
-			tty_kref_put(tty);
-		}
+		tty_port_tty_wakeup(&serial->port);
 		/* response to a write command */
 		hso_kick_transmit(serial);
 	}
···
 static void hso_free_interface(struct usb_interface *interface)
 {
 	struct hso_serial *hso_dev;
-	struct tty_struct *tty;
 	int i;
 
 	for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++) {
 		if (serial_table[i] &&
 		    (serial_table[i]->interface == interface)) {
 			hso_dev = dev2ser(serial_table[i]);
-			tty = tty_port_tty_get(&hso_dev->port);
-			if (tty) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			tty_port_tty_hangup(&hso_dev->port, false);
 			mutex_lock(&hso_dev->parent->mutex);
 			hso_dev->parent->usb_gone = 1;
 			mutex_unlock(&hso_dev->parent->mutex);

drivers/s390/char/sclp_tty.c

···
 static void
 sclp_ttybuf_callback(struct sclp_buffer *buffer, int rc)
 {
-	struct tty_struct *tty;
 	unsigned long flags;
 	void *page;
 
···
 					    struct sclp_buffer, list);
 		spin_unlock_irqrestore(&sclp_tty_lock, flags);
 	} while (buffer && sclp_emit_buffer(buffer, sclp_ttybuf_callback));
-	/* check if the tty needs a wake up call */
-	tty = tty_port_tty_get(&sclp_port);
-	if (tty != NULL) {
-		tty_wakeup(tty);
-		tty_kref_put(tty);
-	}
+
+	tty_port_tty_wakeup(&sclp_port);
 }
 
 static inline void

drivers/s390/char/sclp_vt220.c

···
 static void
 sclp_vt220_process_queue(struct sclp_vt220_request *request)
 {
-	struct tty_struct *tty;
 	unsigned long flags;
 	void *page;
 
···
 	} while (__sclp_vt220_emit(request));
 	if (request == NULL && sclp_vt220_flush_later)
 		sclp_vt220_emit_current();
-	/* Check if the tty needs a wake up call */
-	tty = tty_port_tty_get(&sclp_vt220_port);
-	if (tty) {
-		tty_wakeup(tty);
-		tty_kref_put(tty);
-	}
+	tty_port_tty_wakeup(&sclp_vt220_port);
 }
 
 #define SCLP_BUFFER_MAX_RETRY		1

drivers/staging/fwserial/fwserial.c

···
 			      struct fwtty_transaction *txn)
 {
 	struct fwtty_port *port = txn->port;
-	struct tty_struct *tty;
 	int len;
 
 	fwtty_dbg(port, "rcode: %d", rcode);
···
 		port->stats.dropped += txn->dma_pended.len;
 	}
 
-	if (len < WAKEUP_CHARS) {
-		tty = tty_port_tty_get(&port->port);
-		if (tty) {
-			tty_wakeup(tty);
-			tty_kref_put(tty);
-		}
-	}
+	if (len < WAKEUP_CHARS)
+		tty_port_tty_wakeup(&port->port);
 }
 
 static int fwtty_tx(struct fwtty_port *port, bool drain)

drivers/staging/serqt_usb2/serqt_usb2.c

···
 
 static void qt_write_bulk_callback(struct urb *urb)
 {
-	struct tty_struct *tty;
 	int status;
 	struct quatech_port *quatech_port;
 
···
 
 	quatech_port = urb->context;
 
-	tty = tty_port_tty_get(&quatech_port->port->port);
-
-	if (tty)
-		tty_wakeup(tty);
-	tty_kref_put(tty);
+	tty_port_tty_wakeup(&quatech_port->port->port);
 }
 
 static void qt_interrupt_callback(struct urb *urb)

drivers/tty/amiserial.c

···
 	},
 };
 
-static int __init amiga_serial_init(void)
-{
-	return platform_driver_probe(&amiga_serial_driver, amiga_serial_probe);
-}
-
-module_init(amiga_serial_init);
-
-static void __exit amiga_serial_exit(void)
-{
-	platform_driver_unregister(&amiga_serial_driver);
-}
-
-module_exit(amiga_serial_exit);
+module_platform_driver_probe(amiga_serial_driver, amiga_serial_probe);
 
 
 #if defined(CONFIG_SERIAL_CONSOLE) && !defined(MODULE)

drivers/tty/cyclades.c

···
 					readl(&info->u.cyz.ch_ctrl->rs_status);
 				if (dcd & C_RS_DCD)
 					wake_up_interruptible(&info->port.open_wait);
-				else {
-					struct tty_struct *tty;
-					tty = tty_port_tty_get(&info->port);
-					if (tty) {
-						tty_hangup(tty);
-						tty_kref_put(tty);
-					}
-				}
+				else
+					tty_port_tty_hangup(&info->port, false);
 			}
 			break;
 		case C_CM_MCTS:

drivers/tty/ehv_bytechan.c

···
 static irqreturn_t ehv_bc_tty_tx_isr(int irq, void *data)
 {
 	struct ehv_bc_data *bc = data;
-	struct tty_struct *ttys = tty_port_tty_get(&bc->port);
 
 	ehv_bc_tx_dequeue(bc);
-	if (ttys) {
-		tty_wakeup(ttys);
-		tty_kref_put(ttys);
-	}
+	tty_port_tty_wakeup(&bc->port);
 
 	return IRQ_HANDLED;
 }

drivers/tty/hvc/hvsi.c

···
 {
 	struct hvsi_struct *hp =
 		container_of(work, struct hvsi_struct, writer.work);
-	struct tty_struct *tty;
 	unsigned long flags;
 #ifdef DEBUG
 	static long start_j = 0;
···
 		start_j = 0;
 #endif /* DEBUG */
 		wake_up_all(&hp->emptyq);
-		tty = tty_port_tty_get(&hp->port);
-		if (tty) {
-			tty_wakeup(tty);
-			tty_kref_put(tty);
-		}
+		tty_port_tty_wakeup(&hp->port);
 	}
 
 out:

drivers/tty/ipwireless/hardware.c

···
 	flush_work(&hw->work_rx);
 
 	for (i = 0; i < NL_NUM_OF_ADDRESSES; i++)
-		if (hw->packet_assembler[i] != NULL)
-			kfree(hw->packet_assembler[i]);
+		kfree(hw->packet_assembler[i]);
 
 	for (i = 0; i < NL_NUM_OF_PRIORITIES; i++)
 		list_for_each_entry_safe(tp, tq, &hw->tx_queue[i], queue) {

drivers/tty/moxa.c

···
 
 	/* pci hot-un-plug support */
 	for (a = 0; a < brd->numPorts; a++)
-		if (brd->ports[a].port.flags & ASYNC_INITIALIZED) {
-			struct tty_struct *tty = tty_port_tty_get(
-						&brd->ports[a].port);
-			if (tty) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
-		}
+		if (brd->ports[a].port.flags & ASYNC_INITIALIZED)
+			tty_port_tty_hangup(&brd->ports[a].port, false);
+
 	for (a = 0; a < MAX_PORTS_PER_BOARD; a++)
 		tty_port_destroy(&brd->ports[a].port);
+
 	while (1) {
 		opened = 0;
 		for (a = 0; a < brd->numPorts; a++)
···
 
 static void moxa_new_dcdstate(struct moxa_port *p, u8 dcd)
 {
-	struct tty_struct *tty;
 	unsigned long flags;
 	dcd = !!dcd;
 
···
 	if (dcd != p->DCDState) {
         	p->DCDState = dcd;
         	spin_unlock_irqrestore(&p->port.lock, flags);
-		tty = tty_port_tty_get(&p->port);
-		if (tty && !C_CLOCAL(tty) && !dcd)
-			tty_hangup(tty);
-		tty_kref_put(tty);
+		if (!dcd)
+			tty_port_tty_hangup(&p->port, true);
 	}
 	else
 		spin_unlock_irqrestore(&p->port.lock, flags);

drivers/tty/mxser.c

···
 	mutex_lock(&port->mutex);
 	mxser_close_port(port);
 	mxser_flush_buffer(tty);
+	if (test_bit(ASYNCB_INITIALIZED, &port->flags)) {
+		if (C_HUPCL(tty))
+			tty_port_lower_dtr_rts(port);
+	}
 	mxser_shutdown_port(port);
 	clear_bit(ASYNCB_INITIALIZED, &port->flags);
 	mutex_unlock(&port->mutex);

drivers/tty/n_gsm.c

···
 		pr_debug("DLCI %d goes closed.\n", dlci->addr);
 	dlci->state = DLCI_CLOSED;
 	if (dlci->addr != 0) {
-		struct tty_struct  *tty = tty_port_tty_get(&dlci->port);
-		if (tty) {
-			tty_hangup(tty);
-			tty_kref_put(tty);
-		}
+		tty_port_tty_hangup(&dlci->port, false);
 		kfifo_reset(dlci->fifo);
 	} else
 		dlci->gsm->dead = 1;
···
 	if (tty_port_close_start(&dlci->port, tty, filp) == 0)
 		goto out;
 	gsm_dlci_begin_close(dlci);
+	if (test_bit(ASYNCB_INITIALIZED, &dlci->port.flags)) {
+		if (C_HUPCL(tty))
+			tty_port_lower_dtr_rts(&dlci->port);
+	}
 	tty_port_close_end(&dlci->port, tty);
 	tty_port_tty_set(&dlci->port, NULL);
 out:

drivers/tty/n_tty.c

···
 	if (left && !old_left) {
 		WARN_RATELIMIT(tty->port->itty == NULL,
 				"scheduling with invalid itty\n");
+		/* see if ldisc has been killed - if so, this means that
+		 * even though the ldisc has been halted and ->buf.work
+		 * cancelled, ->buf.work is about to be rescheduled
+		 */
+		WARN_RATELIMIT(test_bit(TTY_LDISC_HALTED, &tty->flags),
+			       "scheduling buffer work for halted ldisc\n");
 		schedule_work(&tty->port->buf.work);
 	}
 }
···
 }
 
 /**
- *	check_unthrottle	-	allow new receive data
- *	@tty; tty device
- *
- *	Check whether to call the driver unthrottle functions
- *
- *	Can sleep, may be called under the atomic_read_lock mutex but
- *	this is not guaranteed.
- */
-static void check_unthrottle(struct tty_struct *tty)
-{
-	if (tty->count)
-		tty_unthrottle(tty);
-}
-
-/**
  *	reset_buffer_flags	-	reset buffer state
  *	@tty: terminal to reset
  *
- *	Reset the read buffer counters, clear the flags,
- *	and make sure the driver is unthrottled. Called
- *	from n_tty_open() and n_tty_flush_buffer().
+ *	Reset the read buffer counters and clear the flags.
+ *	Called from n_tty_open() and n_tty_flush_buffer().
  *
  *	Locking: tty_read_lock for read fields.
  */
 
-static void reset_buffer_flags(struct tty_struct *tty)
+static void reset_buffer_flags(struct n_tty_data *ldata)
 {
-	struct n_tty_data *ldata = tty->disc_data;
 	unsigned long flags;
 
 	raw_spin_lock_irqsave(&ldata->read_lock, flags);
···
 
 	ldata->canon_head = ldata->canon_data = ldata->erasing = 0;
 	bitmap_zero(ldata->read_flags, N_TTY_BUF_SIZE);
-	n_tty_set_room(tty);
 }
 
-/**
- *	n_tty_flush_buffer	-	clean input queue
- *	@tty:	terminal device
- *
- *	Flush the input buffer. Called when the line discipline is
- *	being closed, when the tty layer wants the buffer flushed (eg
- *	at hangup) or when the N_TTY line discipline internally has to
- *	clean the pending queue (for example some signals).
- *
- *	Locking: ctrl_lock, read_lock.
- */
-
-static void n_tty_flush_buffer(struct tty_struct *tty)
+static void n_tty_packet_mode_flush(struct tty_struct *tty)
 {
 	unsigned long flags;
-	/* clear everything and unthrottle the driver */
-	reset_buffer_flags(tty);
-
-	if (!tty->link)
-		return;
 
 	spin_lock_irqsave(&tty->ctrl_lock, flags);
 	if (tty->link->packet) {
···
 		wake_up_interruptible(&tty->link->read_wait);
 	}
 	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+}
+
+/**
+ *	n_tty_flush_buffer	-	clean input queue
+ *	@tty:	terminal device
+ *
+ *	Flush the input buffer. Called when the tty layer wants the
+ *	buffer flushed (eg at hangup) or when the N_TTY line discipline
+ *	internally has to clean the pending queue (for example some signals).
+ *
+ *	Locking: ctrl_lock, read_lock.
+ */
+
+static void n_tty_flush_buffer(struct tty_struct *tty)
+{
+	reset_buffer_flags(tty->disc_data);
+	n_tty_set_room(tty);
+
+	if (tty->link)
+		n_tty_packet_mode_flush(tty);
 }
 
 /**
···
  *	isig		-	handle the ISIG optio
  *	@sig: signal
  *	@tty: terminal
- *	@flush: force flush
  *
- *	Called when a signal is being sent due to terminal input. This
- *	may caus terminal flushing to take place according to the termios
- *	settings and character used. Called from the driver receive_buf
- *	path so serialized.
+ *	Called when a signal is being sent due to terminal input.
+ *	Called from the driver receive_buf path so serialized.
  *
- *	Locking: ctrl_lock, read_lock (both via flush buffer)
+ *	Locking: ctrl_lock
  */
 
-static inline void isig(int sig, struct tty_struct *tty, int flush)
+static inline void isig(int sig, struct tty_struct *tty)
 {
-	if (tty->pgrp)
-		kill_pgrp(tty->pgrp, sig, 1);
-	if (flush || !L_NOFLSH(tty)) {
-		n_tty_flush_buffer(tty);
-		tty_driver_flush_buffer(tty);
+	struct pid *tty_pgrp = tty_get_pgrp(tty);
+	if (tty_pgrp) {
+		kill_pgrp(tty_pgrp, sig, 1);
+		put_pid(tty_pgrp);
 	}
 }
 
···
 	if (I_IGNBRK(tty))
 		return;
 	if (I_BRKINT(tty)) {
-		isig(SIGINT, tty, 1);
+		isig(SIGINT, tty);
+		if (!L_NOFLSH(tty)) {
+			n_tty_flush_buffer(tty);
+			tty_driver_flush_buffer(tty);
+		}
 		return;
 	}
 	if (I_PARMRK(tty)) {
···
 		signal = SIGTSTP;
 		if (c == SUSP_CHAR(tty)) {
 send_signal:
-			/*
-			 * Note that we do not use isig() here because we want
-			 * the order to be:
-			 * 1) flush, 2) echo, 3) signal
-			 */
 			if (!L_NOFLSH(tty)) {
 				n_tty_flush_buffer(tty);
 				tty_driver_flush_buffer(tty);
···
 				echo_char(c, tty);
 				process_echoes(tty);
 			}
-			if (tty->pgrp)
-				kill_pgrp(tty->pgrp, signal, 1);
+			isig(signal, tty);
 			return;
 		}
 	}
···
 	 * mode.  We don't want to throttle the driver if we're in
 	 * canonical mode and don't have a newline yet!
 	 */
-	if (tty->receive_room < TTY_THRESHOLD_THROTTLE)
-		tty_throttle(tty);
-
-        /* FIXME: there is a tiny race here if the receive room check runs
-           before the other work executes and empties the buffer (upping
-           the receiving room and unthrottling. We then throttle and get
-           stuck. This has been observed and traced down by Vincent Pillet/
-           We need to address this when we sort out out the rx path locking */
+	while (1) {
+		tty_set_flow_change(tty, TTY_THROTTLE_SAFE);
+		if (tty->receive_room >= TTY_THRESHOLD_THROTTLE)
+			break;
+		if (!tty_throttle_safe(tty))
+			break;
+	}
+	__tty_set_flow_change(tty, 0);
 }
 
 int is_ignored(int sig)
···
 {
 	struct n_tty_data *ldata = tty->disc_data;
 
-	n_tty_flush_buffer(tty);
+	if (tty->link)
+		n_tty_packet_mode_flush(tty);
+
 	kfree(ldata->read_buf);
 	kfree(ldata->echo_buf);
 	kfree(ldata);
···
 		goto err_free_bufs;
 
 	tty->disc_data = ldata;
-	reset_buffer_flags(tty);
-	tty_unthrottle(tty);
+	reset_buffer_flags(tty->disc_data);
 	ldata->column = 0;
-	n_tty_set_termios(tty, NULL);
 	tty->minimum_to_wake = 1;
 	tty->closing = 0;
+	/* indicate buffer work may resume */
+	clear_bit(TTY_LDISC_HALTED, &tty->flags);
+	n_tty_set_termios(tty, NULL);
+	tty_unthrottle(tty);
 
 	return 0;
 err_free_bufs:
···
  *	and if appropriate send any needed signals and return a negative
  *	error code if action should be taken.
  *
- *	FIXME:
- *	Locking: None - redirected write test is safe, testing
- *	current->signal should possibly lock current->sighand
- *	pgrp locking ?
+ *	Locking: redirected write test is safe
+ *		 current->signal->tty check is safe
+ *		 ctrl_lock to safely reference tty->pgrp
  */
 
 static int job_control(struct tty_struct *tty, struct file *file)
···
 	/* NOTE: not yet done after every sleep pending a thorough
 	   check of the logic of this change. -- jlc */
 	/* don't stop on /dev/console */
-	if (file->f_op->write != redirected_tty_write &&
-	    current->signal->tty == tty) {
-		if (!tty->pgrp)
-			printk(KERN_ERR "n_tty_read: no tty->pgrp!\n");
-		else if (task_pgrp(current) != tty->pgrp) {
-			if (is_ignored(SIGTTIN) ||
-			    is_current_pgrp_orphaned())
-				return -EIO;
-			kill_pgrp(task_pgrp(current), SIGTTIN, 1);
-			set_thread_flag(TIF_SIGPENDING);
-			return -ERESTARTSYS;
-		}
+	if (file->f_op->write == redirected_tty_write ||
+	    current->signal->tty != tty)
+		return 0;
+
+	spin_lock_irq(&tty->ctrl_lock);
+	if (!tty->pgrp)
+		printk(KERN_ERR "n_tty_read: no tty->pgrp!\n");
+	else if (task_pgrp(current) != tty->pgrp) {
+		spin_unlock_irq(&tty->ctrl_lock);
+		if (is_ignored(SIGTTIN) || is_current_pgrp_orphaned())
+			return -EIO;
+		kill_pgrp(task_pgrp(current), SIGTTIN, 1);
+		set_thread_flag(TIF_SIGPENDING);
+		return -ERESTARTSYS;
 	}
+	spin_unlock_irq(&tty->ctrl_lock);
 	return 0;
 }
 
···
 		 * longer than TTY_THRESHOLD_UNTHROTTLE in canonical mode,
 		 * we won't get any more characters.
 		 */
-		if (n_tty_chars_in_buffer(tty) <= TTY_THRESHOLD_UNTHROTTLE) {
+		while (1) {
+			tty_set_flow_change(tty, TTY_UNTHROTTLE_SAFE);
+			if (n_tty_chars_in_buffer(tty) > TTY_THRESHOLD_UNTHROTTLE)
+				break;
+			if (!tty->count)
+				break;
 			n_tty_set_room(tty);
-			check_unthrottle(tty);
+			if (!tty_unthrottle_safe(tty))
+				break;
 		}
+		__tty_set_flow_change(tty, 0);
 
 		if (b - buf >= minimum)
 			break;

drivers/tty/nozomi.c

···
 	const u8 toggle = port->toggle_ul;
 	void __iomem *addr = port->ul_addr[toggle];
 	const u32 ul_size = port->ul_size[toggle];
-	struct tty_struct *tty = tty_port_tty_get(&port->port);
 
 	/* Get data from tty and place in buf for now */
 	size = kfifo_out(&port->fifo_ul, dc->send_buf,
···
 
 	if (size == 0) {
 		DBG4("No more data to send, disable link:");
-		tty_kref_put(tty);
 		return 0;
 	}
 
···
 	write_mem32(addr, (u32 *) &size, 4);
 	write_mem32(addr + 4, (u32 *) dc->send_buf, size);
 
-	if (tty)
-		tty_wakeup(tty);
+	tty_port_tty_wakeup(&port->port);
 
-	tty_kref_put(tty);
 	return 1;
 }
 
···
 
 	DBG1(" ");
 
-	for (i = 0; i < MAX_PORT; ++i) {
-		struct tty_struct *tty = tty_port_tty_get(&dc->port[i].port);
-		if (tty && list_empty(&tty->hangup_work.entry))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	for (i = 0; i < MAX_PORT; ++i)
+		tty_port_tty_hangup(&dc->port[i].port, false);
+
 	/* Racy below - surely should wait for scheduled work to be done or
 	   complete off a hangup method ? */
 	while (dc->open_ttys)

drivers/tty/pty.c

···
 	return retval;
 }
 
-/* this is called once with whichever end is closed last */
-static void pty_unix98_shutdown(struct tty_struct *tty)
-{
-	devpts_kill_index(tty->driver_data, tty->index);
-}
-
 static void pty_cleanup(struct tty_struct *tty)
 {
-	tty->port->itty = NULL;
 	tty_port_put(tty->port);
 }
 
···
 
 static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
 {
+}
+
+/* this is called once with whichever end is closed last */
+static void pty_unix98_shutdown(struct tty_struct *tty)
+{
+	devpts_kill_index(tty->driver_data, tty->index);
 }
 
 static const struct tty_operations ptm_unix98_ops = {

drivers/tty/rocket.c

···
 
 	/*  Loop sending data to FIFO until done or FIFO full */
 	while (1) {
-		if (tty->stopped || tty->hw_stopped)
+		if (tty->stopped)
 			break;
 		c = min(info->xmit_fifo_room, info->xmit_cnt);
 		c = min(c, XMIT_BUF_SIZE - info->xmit_tail);
···
 		       (ChanStatus & CD_ACT) ? "on" : "off");
 #endif
 		if (!(ChanStatus & CD_ACT) && info->cd_status) {
-			struct tty_struct *tty;
 #ifdef ROCKET_DEBUG_HANGUP
 			printk(KERN_INFO "CD drop, calling hangup.\n");
 #endif
-			tty = tty_port_tty_get(&info->port);
-			if (tty) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			tty_port_tty_hangup(&info->port, false);
 		}
 		info->cd_status = (ChanStatus & CD_ACT) ? 1 : 0;
 		wake_up_interruptible(&info->port.open_wait);
···
 
 	/* Handle transition away from B0 status */
 	if (!(old_termios->c_cflag & CBAUD) && (tty->termios.c_cflag & CBAUD)) {
-		if (!tty->hw_stopped || !(tty->termios.c_cflag & CRTSCTS))
-			sSetRTS(cp);
+		sSetRTS(cp);
 		sSetDTR(cp);
 	}
 
-	if ((old_termios->c_cflag & CRTSCTS) && !(tty->termios.c_cflag & CRTSCTS)) {
-		tty->hw_stopped = 0;
+	if ((old_termios->c_cflag & CRTSCTS) && !(tty->termios.c_cflag & CRTSCTS))
 		rp_start(tty);
-	}
 }
 
 static int rp_break(struct tty_struct *tty, int break_state)
···
 	spin_lock_irqsave(&info->slock, flags);
 	cp = &info->channel;
 
-	if (!tty->stopped && !tty->hw_stopped && info->xmit_fifo_room == 0)
+	if (!tty->stopped && info->xmit_fifo_room == 0)
 		info->xmit_fifo_room = TXFIFO_SIZE - sGetTxCnt(cp);
 
-	if (tty->stopped || tty->hw_stopped || info->xmit_fifo_room == 0 || info->xmit_cnt != 0) {
+	if (tty->stopped || info->xmit_fifo_room == 0 || info->xmit_cnt != 0) {
 		info->xmit_buf[info->xmit_head++] = ch;
 		info->xmit_head &= XMIT_BUF_SIZE - 1;
 		info->xmit_cnt++;
···
 #endif
 	cp = &info->channel;
 
-	if (!tty->stopped && !tty->hw_stopped && info->xmit_fifo_room < count)
+	if (!tty->stopped && info->xmit_fifo_room < count)
 		info->xmit_fifo_room = TXFIFO_SIZE - sGetTxCnt(cp);
 
         /*
 	 *  If the write queue for the port is empty, and there is FIFO space, stuff bytes 
 	 *  into FIFO.  Use the write queue for temp storage.
          */
-	if (!tty->stopped && !tty->hw_stopped && info->xmit_cnt == 0 && info->xmit_fifo_room > 0) {
+	if (!tty->stopped && info->xmit_cnt == 0 && info->xmit_fifo_room > 0) {
 		c = min(count, info->xmit_fifo_room);
 		b = buf;
 
···
 		retval += c;
 	}
 
-	if ((retval > 0) && !tty->stopped && !tty->hw_stopped)
+	if ((retval > 0) && !tty->stopped)
 		set_bit((info->aiop * 8) + info->chan, (void *) &xmit_flags[info->board]);
 	
 end:
···
 		return (CtlP->NumAiop);
 }
 
+#ifdef CONFIG_PCI
 /***************************************************************************
 Function: sPCIInitController
 Purpose:  Initialization of controller global registers and controller
···
 	else
 		return (CtlP->NumAiop);
 }
+
+/*  Resets the speaker controller on RocketModem II and III devices */
+static void rmSpeakerReset(CONTROLLER_T * CtlP, unsigned long model)
+{
+	ByteIO_t addr;
+
+	/* RocketModem II speaker control is at the 8th port location of offset 0x40 */
+	if ((model == MODEL_RP4M) || (model == MODEL_RP6M)) {
+		addr = CtlP->AiopIO[0] + 0x4F;
+		sOutB(addr, 0);
+	}
+
+	/* RocketModem III speaker control is at the 1st port location of offset 0x80 */
+	if ((model == MODEL_UPCI_RM3_8PORT)
+	    || (model == MODEL_UPCI_RM3_4PORT)) {
+		addr = CtlP->AiopIO[0] + 0x88;
+		sOutB(addr, 0);
+	}
+}
+#endif
 
 /***************************************************************************
 Function: sReadAiopID
···
 	if (!on)
 		addr += 8;
 	sOutB(addr + chan, 0);	/* apply or remove reset */
-}
-
-/*  Resets the speaker controller on RocketModem II and III devices */
-static void rmSpeakerReset(CONTROLLER_T * CtlP, unsigned long model)
-{
-	ByteIO_t addr;
-
-	/* RocketModem II speaker control is at the 8th port location of offset 0x40 */
-	if ((model == MODEL_RP4M) || (model == MODEL_RP6M)) {
-		addr = CtlP->AiopIO[0] + 0x4F;
-		sOutB(addr, 0);
-	}
-
-	/* RocketModem III speaker control is at the 1st port location of offset 0x80 */
-	if ((model == MODEL_UPCI_RM3_8PORT)
-	    || (model == MODEL_UPCI_RM3_4PORT)) {
-		addr = CtlP->AiopIO[0] + 0x88;
-		sOutB(addr, 0);
-	}
 }
 
 /*  Returns the line number given the controller (board), aiop and channel number */

drivers/tty/serial/68328serial.c

···
 	/* Enable transmitter */
 	local_irq_save(flags);
 
-	if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
-			!info->xmit_buf) {
+	if (info->xmit_cnt <= 0 || tty->stopped || !info->xmit_buf) {
 		local_irq_restore(flags);
 		return;
 	}
···
 		total += c;
 	}
 
-	if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped) {
+	if (info->xmit_cnt && !tty->stopped) {
 		/* Enable transmitter */
 		local_irq_disable();		
 #ifndef USE_INTS
···
 	change_speed(info, tty);
 
 	if ((old_termios->c_cflag & CRTSCTS) &&
-	    !(tty->termios.c_cflag & CRTSCTS)) {
-		tty->hw_stopped = 0;
+	    !(tty->termios.c_cflag & CRTSCTS))
 		rs_start(tty);
-	}
 	
 }
 

drivers/tty/serial/8250/8250.h

···
  * is cleared, the machine locks up with endless interrupts.
  */
 #define ALPHA_KLUDGE_MCR  (UART_MCR_OUT2 | UART_MCR_OUT1)
-#elif defined(CONFIG_SBC8560)
-/*
- * WindRiver did something similarly broken on their SBC8560 board. The
- * UART tristates its IRQ output while OUT2 is clear, but they pulled
- * the interrupt line _up_ instead of down, so if we register the IRQ
- * while the UART is in that state, we die in an IRQ storm. */
-#define ALPHA_KLUDGE_MCR (UART_MCR_OUT2)
 #else
 #define ALPHA_KLUDGE_MCR 0
 #endif

drivers/tty/serial/8250/8250_core.c

···
 	if (nr_uarts > UART_NR)
 		nr_uarts = UART_NR;
 
-	for (i = 0; i < nr_uarts; i++) {
+	for (i = 0; i < UART_NR; i++) {
 		struct uart_8250_port *up = &serial8250_ports[i];
 		struct uart_port *port = &up->port;
 
···
 	 * if so, search for the first available port that does have
 	 * console support.
 	 */
-	if (co->index >= nr_uarts)
+	if (co->index >= UART_NR)
 		co->index = 0;
 	port = &serial8250_ports[co->index].port;
 	if (!port->iobase && !port->membase)
···
 	int line;
 	struct uart_port *port;
 
-	for (line = 0; line < nr_uarts; line++) {
+	for (line = 0; line < UART_NR; line++) {
 		port = &serial8250_ports[line].port;
 		if (uart_match_port(p, port))
 			return line;
···
 {
 	int i;
 
-	for (i = 0; i < nr_uarts; i++) {
+	for (i = 0; i < UART_NR; i++) {
 		struct uart_8250_port *up = &serial8250_ports[i];
 
 		if (up->port.dev == &dev->dev)
···
 	/*
 	 * First, find a port entry which matches.
 	 */
-	for (i = 0; i < nr_uarts; i++)
+	for (i = 0; i < UART_NR; i++)
 		if (uart_match_port(&serial8250_ports[i].port, port))
 			return &serial8250_ports[i];
 
···
 	 * free entry.  We look for one which hasn't been previously
 	 * used (indicated by zero iobase).
 	 */
-	for (i = 0; i < nr_uarts; i++)
+	for (i = 0; i < UART_NR; i++)
 		if (serial8250_ports[i].port.type == PORT_UNKNOWN &&
 		    serial8250_ports[i].port.iobase == 0)
 			return &serial8250_ports[i];
···
 	 * That also failed.  Last resort is to find any entry which
 	 * doesn't have a real port associated with it.
 	 */
-	for (i = 0; i < nr_uarts; i++)
+	for (i = 0; i < UART_NR; i++)
 		if (serial8250_ports[i].port.type == PORT_UNKNOWN)
 			return &serial8250_ports[i];
 
···
 		uart->port.fifosize	= up->port.fifosize;
 		uart->tx_loadsz		= up->tx_loadsz;
 		uart->capabilities	= up->capabilities;
+
+		/* Take tx_loadsz from fifosize if it wasn't set separately */
+		if (uart->port.fifosize && !uart->tx_loadsz)
+			uart->tx_loadsz = uart->port.fifosize;
 
 		if (up->port.dev)
 			uart->port.dev = up->port.dev;

drivers/tty/serial/8250/8250_dma.c

···
 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 		uart_write_wakeup(&p->port);
 
-	if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) {
+	if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port))
 		serial8250_tx_dma(p);
-		uart_write_wakeup(&p->port);
-	}
 }
 
 static void __dma_rx_complete(void *param)
···
 	struct circ_buf			*xmit = &p->port.state->xmit;
 	struct dma_async_tx_descriptor	*desc;
 
-	if (dma->tx_running)
-		return -EBUSY;
+	if (uart_tx_stopped(&p->port) || dma->tx_running ||
+	    uart_circ_empty(xmit))
+		return 0;
 
 	dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
-	if (!dma->tx_size)
-		return -EINVAL;
 
 	desc = dmaengine_prep_slave_single(dma->txchan,
 					   dma->tx_addr + xmit->tail,
···
 	struct dma_tx_state		state;
 	int				dma_status;
 
-	/*
-	 * If RCVR FIFO trigger level was not reached, complete the transfer and
-	 * let 8250.c copy the remaining data.
-	 */
-	if ((iir & 0x3f) == UART_IIR_RX_TIMEOUT) {
-		dma_status = dmaengine_tx_status(dma->rxchan, dma->rx_cookie,
-						&state);
+	dma_status = dmaengine_tx_status(dma->rxchan, dma->rx_cookie, &state);
+
+	switch (iir & 0x3f) {
+	case UART_IIR_RLSI:
+		/* 8250_core handles errors and break interrupts */
+		return -EIO;
+	case UART_IIR_RX_TIMEOUT:
+		/*
+		 * If RCVR FIFO trigger level was not reached, complete the
+		 * transfer and let 8250_core copy the remaining data.
+		 */
 		if (dma_status == DMA_IN_PROGRESS) {
 			dmaengine_pause(dma->rxchan);
 			__dma_rx_complete(p);
 		}
 		return -ETIMEDOUT;
+	default:
+		break;
 	}
+
+	if (dma_status)
+		return 0;
 
 	desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr,
 					   dma->rx_size, DMA_DEV_TO_MEM,
···
 	struct uart_8250_dma	*dma = p->dma;
 	dma_cap_mask_t		mask;
 
-	dma->rxconf.src_addr = p->port.mapbase + UART_RX;
-	dma->txconf.dst_addr = p->port.mapbase + UART_TX;
+	/* Default slave configuration parameters */
+	dma->rxconf.direction		= DMA_DEV_TO_MEM;
+	dma->rxconf.src_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
+	dma->rxconf.src_addr		= p->port.mapbase + UART_RX;
+
+	dma->txconf.direction		= DMA_MEM_TO_DEV;
+	dma->txconf.dst_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
+	dma->txconf.dst_addr		= p->port.mapbase + UART_TX;
 
 	dma_cap_zero(mask);
 	dma_cap_set(DMA_SLAVE, mask);
 
 	/* Get a channel for RX */
-	dma->rxchan = dma_request_channel(mask, dma->fn, dma->rx_param);
+	dma->rxchan = dma_request_slave_channel_compat(mask,
+						       dma->fn, dma->rx_param,
+						       p->port.dev, "rx");
 	if (!dma->rxchan)
 		return -ENODEV;
 
 	dmaengine_slave_config(dma->rxchan, &dma->rxconf);
 
 	/* Get a channel for TX */
-	dma->txchan = dma_request_channel(mask, dma->fn, dma->tx_param);
+	dma->txchan = dma_request_slave_channel_compat(mask,
+						       dma->fn, dma->tx_param,
+						       p->port.dev, "tx");
 	if (!dma->txchan) {
 		dma_release_channel(dma->rxchan);
 		return -ENODEV;

drivers/tty/serial/8250/8250_dw.c

···
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/acpi.h>
+#include <linux/clk.h>
+#include <linux/pm_runtime.h>
 
 #include "8250.h"
 
···
 #define DW_UART_USR	0x1f /* UART Status Register */
 #define DW_UART_CPR	0xf4 /* Component Parameter Register */
 #define DW_UART_UCV	0xf8 /* UART Component Version */
-
-/* Intel Low Power Subsystem specific */
-#define LPSS_PRV_CLOCK_PARAMS 0x800
 
 /* Component Parameter Register bits */
 #define DW_UART_CPR_ABP_DATA_WIDTH	(3 << 0)
···
 
 
 struct dw8250_data {
-	int	last_lcr;
-	int	line;
+	int		last_lcr;
+	int		line;
+	struct clk	*clk;
 };
 
 static void dw8250_serial_out(struct uart_port *p, int offset, int value)
···
 	return 0;
 }
 
+static void
+dw8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old)
+{
+	if (!state)
+		pm_runtime_get_sync(port->dev);
+
+	serial8250_do_pm(port, state, old);
+
+	if (state)
+		pm_runtime_put_sync_suspend(port->dev);
+}
+
 static int dw8250_probe_of(struct uart_port *p)
 {
 	struct device_node	*np = p->dev->of_node;
···
 	if (!of_property_read_u32(np, "reg-shift", &val))
 		p->regshift = val;
 
+	/* clock got configured through clk api, all done */
+	if (p->uartclk)
+		return 0;
+
+	/* try to find out clock frequency from DT as fallback */
 	if (of_property_read_u32(np, "clock-frequency", &val)) {
-		dev_err(p->dev, "no clock-frequency property set\n");
+		dev_err(p->dev, "clk or clock-frequency not defined\n");
 		return -EINVAL;
 	}
 	p->uartclk = val;
···
 }
 
 #ifdef CONFIG_ACPI
-static bool dw8250_acpi_dma_filter(struct dma_chan *chan, void *parm)
-{
-	return chan->chan_id == *(int *)parm;
-}
-
-static acpi_status
-dw8250_acpi_walk_resource(struct acpi_resource *res, void *data)
-{
-	struct uart_port		*p = data;
-	struct uart_8250_port		*port;
-	struct uart_8250_dma		*dma;
-	struct acpi_resource_fixed_dma	*fixed_dma;
-	struct dma_slave_config		*slave;
-
-	port = container_of(p, struct uart_8250_port, port);
-
-	switch (res->type) {
-	case ACPI_RESOURCE_TYPE_FIXED_DMA:
-		fixed_dma = &res->data.fixed_dma;
-
-		/* TX comes first */
-		if (!port->dma) {
-			dma = devm_kzalloc(p->dev, sizeof(*dma), GFP_KERNEL);
-			if (!dma)
-				return AE_NO_MEMORY;
-
-			port->dma = dma;
-			slave = &dma->txconf;
-
-			slave->direction	= DMA_MEM_TO_DEV;
-			slave->dst_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
-			slave->slave_id		= fixed_dma->request_lines;
-			slave->dst_maxburst	= port->tx_loadsz / 4;
-
-			dma->tx_chan_id		= fixed_dma->channels;
-			dma->tx_param		= &dma->tx_chan_id;
-			dma->fn			= dw8250_acpi_dma_filter;
-		} else {
-			dma = port->dma;
-			slave = &dma->rxconf;
-
-			slave->direction	= DMA_DEV_TO_MEM;
-			slave->src_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;
-			slave->slave_id		= fixed_dma->request_lines;
-			slave->src_maxburst	= p->fifosize / 4;
-
-			dma->rx_chan_id		= fixed_dma->channels;
-			dma->rx_param		= &dma->rx_chan_id;
-		}
-
-		break;
-	}
-
-	return AE_OK;
-}
-
-static int dw8250_probe_acpi(struct uart_port *p)
+static int dw8250_probe_acpi(struct uart_8250_port *up)
 {
 	const struct acpi_device_id *id;
-	acpi_status status;
-	u32 reg;
+	struct uart_port *p = &up->port;
 
 	id = acpi_match_device(p->dev->driver->acpi_match_table, p->dev);
 	if (!id)
···
 	p->serial_in = dw8250_serial_in32;
 	p->serial_out = dw8250_serial_out32;
 	p->regshift = 2;
-	p->uartclk = (unsigned int)id->driver_data;
 
-	status = acpi_walk_resources(ACPI_HANDLE(p->dev), METHOD_NAME__CRS,
-				     dw8250_acpi_walk_resource, p);
-	if (ACPI_FAILURE(status)) {
-		dev_err_ratelimited(p->dev, "%s failed \"%s\"\n", __func__,
-				    acpi_format_exception(status));
-		return -ENODEV;
-	}
+	if (!p->uartclk)
+		p->uartclk = (unsigned int)id->driver_data;
 
-	/* Fix Haswell issue where the clocks do not get enabled */
-	if (!strcmp(id->id, "INT33C4") || !strcmp(id->id, "INT33C5")) {
-		reg = readl(p->membase + LPSS_PRV_CLOCK_PARAMS);
-		writel(reg | 1, p->membase + LPSS_PRV_CLOCK_PARAMS);
-	}
+	up->dma = devm_kzalloc(p->dev, sizeof(*up->dma), GFP_KERNEL);
+	if (!up->dma)
+		return -ENOMEM;
+
+	up->dma->rxconf.src_maxburst = p->fifosize / 4;
+	up->dma->txconf.dst_maxburst = p->fifosize / 4;
 
 	return 0;
 }
 #else
-static inline int dw8250_probe_acpi(struct uart_port *p)
+static inline int dw8250_probe_acpi(struct uart_8250_port *up)
 {
 	return -ENODEV;
 }
···
 		p->flags |= UPF_FIXED_TYPE;
 		p->fifosize = DW_UART_CPR_FIFO_SIZE(reg);
 		up->tx_loadsz = p->fifosize;
+		up->capabilities = UART_CAP_FIFO;
 	}
+
+	if (reg & DW_UART_CPR_AFCE_MODE)
+		up->capabilities |= UART_CAP_AFE;
 }
 
 static int dw8250_probe(struct platform_device *pdev)
···
 	uart.port.mapbase = regs->start;
 	uart.port.irq = irq->start;
 	uart.port.handle_irq = dw8250_handle_irq;
+	uart.port.pm = dw8250_do_pm;
 	uart.port.type = PORT_8250;
 	uart.port.flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_FIXED_PORT;
 	uart.port.dev = &pdev->dev;
 
-	uart.port.membase = ioremap(regs->start, resource_size(regs));
+	uart.port.membase = devm_ioremap(&pdev->dev, regs->start,
+					 resource_size(regs));
 	if (!uart.port.membase)
 		return -ENOMEM;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->clk = devm_clk_get(&pdev->dev, NULL);
+	if (!IS_ERR(data->clk)) {
+		clk_prepare_enable(data->clk);
+		uart.port.uartclk = clk_get_rate(data->clk);
+	}
 
 	uart.port.iotype = UPIO_MEM;
 	uart.port.serial_in = dw8250_serial_in;
 	uart.port.serial_out = dw8250_serial_out;
+	uart.port.private_data = data;
 
 	dw8250_setup_port(&uart);
 
···
 		if (err)
 			return err;
 	} else if (ACPI_HANDLE(&pdev->dev)) {
-		err = dw8250_probe_acpi(&uart.port);
+		err = dw8250_probe_acpi(&uart);
 		if (err)
 			return err;
 	} else {
 		return -ENODEV;
 	}
 
-	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
-	uart.port.private_data = data;
-
 	data->line = serial8250_register_8250_port(&uart);
 	if (data->line < 0)
 		return data->line;
 
 	platform_set_drvdata(pdev, data);
+
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
 
 	return 0;
 }
···
 {
 	struct dw8250_data *data = platform_get_drvdata(pdev);
 
+	pm_runtime_get_sync(&pdev->dev);
+
 	serial8250_unregister_port(data->line);
+
+	if (!IS_ERR(data->clk))
+		clk_disable_unprepare(data->clk);
+
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_put_noidle(&pdev->dev);
 
 	return 0;
 }
 
 #ifdef CONFIG_PM
-static int dw8250_suspend(struct platform_device *pdev, pm_message_t state)
+static int dw8250_suspend(struct device *dev)
 {
-	struct dw8250_data *data = platform_get_drvdata(pdev);
+	struct dw8250_data *data = dev_get_drvdata(dev);
 
 	serial8250_suspend_port(data->line);
 
 	return 0;
 }
 
-static int dw8250_resume(struct platform_device *pdev)
+static int dw8250_resume(struct device *dev)
 {
-	struct dw8250_data *data = platform_get_drvdata(pdev);
+	struct dw8250_data *data = dev_get_drvdata(dev);
 
 	serial8250_resume_port(data->line);
 
 	return 0;
 }
-#else
-#define dw8250_suspend NULL
-#define dw8250_resume NULL
 #endif /* CONFIG_PM */
+
+#ifdef CONFIG_PM_RUNTIME
+static int dw8250_runtime_suspend(struct device *dev)
+{
+	struct dw8250_data *data = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(data->clk);
+
+	return 0;
+}
+
+static int dw8250_runtime_resume(struct device *dev)
+{
+	struct dw8250_data *data = dev_get_drvdata(dev);
+
+	clk_prepare_enable(data->clk);
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops dw8250_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(dw8250_suspend, dw8250_resume)
+	SET_RUNTIME_PM_OPS(dw8250_runtime_suspend, dw8250_runtime_resume, NULL)
+};
 
 static const struct of_device_id dw8250_of_match[] = {
 	{ .compatible = "snps,dw-apb-uart" },
···
 MODULE_DEVICE_TABLE(of, dw8250_of_match);
 
 static const struct acpi_device_id dw8250_acpi_match[] = {
-	{ "INT33C4", 100000000 },
-	{ "INT33C5", 100000000 },
+	{ "INT33C4", 0 },
+	{ "INT33C5", 0 },
 	{ },
 };
 MODULE_DEVICE_TABLE(acpi, dw8250_acpi_match);
···
 	.driver = {
 		.name		= "dw-apb-uart",
 		.owner		= THIS_MODULE,
+		.pm		= &dw8250_pm_ops,
 		.of_match_table	= dw8250_of_match,
 		.acpi_match_table = ACPI_PTR(dw8250_acpi_match),
 	},
 	.probe			= dw8250_probe,
 	.remove			= dw8250_remove,
-	.suspend		= dw8250_suspend,
-	.resume			= dw8250_resume,
 };
 
 module_platform_driver(dw8250_platform_driver);

drivers/tty/serial/amba-pl011.c

···
  * and hooked into this driver.
  */
 
+
 #if defined(CONFIG_SERIAL_AMBA_PL011_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 #define SUPPORT_SYSRQ
 #endif
···
 /* There is by now at least one vendor with differing details, so handle it */
 struct vendor_data {
 	unsigned int		ifls;
-	unsigned int		fifosize;
 	unsigned int		lcrh_tx;
 	unsigned int		lcrh_rx;
 	bool			oversampling;
 	bool			dma_threshold;
 	bool			cts_event_workaround;
+
+	unsigned int (*get_fifosize)(unsigned int periphid);
 };
+
+static unsigned int get_fifosize_arm(unsigned int periphid)
+{
+	unsigned int rev = (periphid >> 20) & 0xf;
+	return rev < 3 ? 16 : 32;
+}
 
 static struct vendor_data vendor_arm = {
 	.ifls			= UART011_IFLS_RX4_8|UART011_IFLS_TX4_8,
-	.fifosize		= 16,
 	.lcrh_tx		= UART011_LCRH,
 	.lcrh_rx		= UART011_LCRH,
 	.oversampling		= false,
 	.dma_threshold		= false,
 	.cts_event_workaround	= false,
+	.get_fifosize		= get_fifosize_arm,
 };
+
+static unsigned int get_fifosize_st(unsigned int periphid)
+{
+	return 64;
+}
 
 static struct vendor_data vendor_st = {
 	.ifls			= UART011_IFLS_RX_HALF|UART011_IFLS_TX_HALF,
-	.fifosize		= 64,
 	.lcrh_tx		= ST_UART011_LCRH_TX,
 	.lcrh_rx		= ST_UART011_LCRH_RX,
 	.oversampling		= true,
 	.dma_threshold		= true,
 	.cts_event_workaround	= true,
+	.get_fifosize		= get_fifosize_st,
 };
 
 static struct uart_amba_port *amba_ports[UART_NR];
···
 	struct pl011_sgbuf	sgbuf_b;
 	dma_cookie_t		cookie;
 	bool			running;
+	struct timer_list	timer;
+	unsigned int last_residue;
+	unsigned long last_jiffies;
+	bool auto_poll_rate;
+	unsigned int poll_rate;
+	unsigned int poll_timeout;
 };
 
 struct pl011_dmatx_data {
···
 static int pl011_sgbuf_init(struct dma_chan *chan, struct pl011_sgbuf *sg,
 	enum dma_data_direction dir)
 {
-	sg->buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL);
+	dma_addr_t dma_addr;
+
+	sg->buf = dma_alloc_coherent(chan->device->dev,
+		PL011_DMA_BUFFER_SIZE, &dma_addr, GFP_KERNEL);
 	if (!sg->buf)
 		return -ENOMEM;
 
-	sg_init_one(&sg->sg, sg->buf, PL011_DMA_BUFFER_SIZE);
+	sg_init_table(&sg->sg, 1);
+	sg_set_page(&sg->sg, phys_to_page(dma_addr),
+		PL011_DMA_BUFFER_SIZE, offset_in_page(dma_addr));
+	sg_dma_address(&sg->sg) = dma_addr;
 
-	if (dma_map_sg(chan->device->dev, &sg->sg, 1, dir) != 1) {
-		kfree(sg->buf);
-		return -EINVAL;
-	}
 	return 0;
 }
 
···
 	enum dma_data_direction dir)
 {
 	if (sg->buf) {
-		dma_unmap_sg(chan->device->dev, &sg->sg, 1, dir);
-		kfree(sg->buf);
+		dma_free_coherent(chan->device->dev,
+			PL011_DMA_BUFFER_SIZE, sg->buf,
+			sg_dma_address(&sg->sg));
 	}
 }
 
···
 
 		dmaengine_slave_config(chan, &rx_conf);
 		uap->dmarx.chan = chan;
+
+		if (plat->dma_rx_poll_enable) {
+			/* Set poll rate if specified. */
+			if (plat->dma_rx_poll_rate) {
+				uap->dmarx.auto_poll_rate = false;
+				uap->dmarx.poll_rate = plat->dma_rx_poll_rate;
+			} else {
+				/*
+				 * 100 ms defaults to poll rate if not
+				 * specified. This will be adjusted with
+				 * the baud rate at set_termios.
+				 */
+				uap->dmarx.auto_poll_rate = true;
+				uap->dmarx.poll_rate =  100;
+			}
+			/* 3 secs defaults poll_timeout if not specified. */
+			if (plat->dma_rx_poll_timeout)
+				uap->dmarx.poll_timeout =
+					plat->dma_rx_poll_timeout;
+			else
+				uap->dmarx.poll_timeout = 3000;
+		} else
+			uap->dmarx.auto_poll_rate = false;
 
 		dev_info(uap->port.dev, "DMA channel RX %s\n",
 			 dma_chan_name(uap->dmarx.chan));
···
 	struct tty_port *port = &uap->port.state->port;
 	struct pl011_sgbuf *sgbuf = use_buf_b ?
 		&uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a;
-	struct device *dev = uap->dmarx.chan->device->dev;
 	int dma_count = 0;
 	u32 fifotaken = 0; /* only used for vdbg() */
 
-	/* Pick everything from the DMA first */
+	struct pl011_dmarx_data *dmarx = &uap->dmarx;
+	int dmataken = 0;
+
+	if (uap->dmarx.poll_rate) {
+		/* The data can be taken by polling */
+		dmataken = sgbuf->sg.length - dmarx->last_residue;
+		/* Recalculate the pending size */
+		if (pending >= dmataken)
+			pending -= dmataken;
+	}
+
+	/* Pick the remain data from the DMA */
 	if (pending) {
-		/* Sync in buffer */
-		dma_sync_sg_for_cpu(dev, &sgbuf->sg, 1, DMA_FROM_DEVICE);
 
 		/*
 		 * First take all chars in the DMA pipe, then look in the FIFO.
 		 * Note that tty_insert_flip_buf() tries to take as many chars
 		 * as it can.
 		 */
-		dma_count = tty_insert_flip_string(port, sgbuf->buf, pending);
-
-		/* Return buffer to device */
-		dma_sync_sg_for_device(dev, &sgbuf->sg, 1, DMA_FROM_DEVICE);
+		dma_count = tty_insert_flip_string(port, sgbuf->buf + dmataken,
+				pending);
 
 		uap->port.icount.rx += dma_count;
 		if (dma_count < pending)
 			dev_warn(uap->port.dev,
 				 "couldn't insert all characters (TTY is full?)\n");
 	}
+
+	/* Reset the last_residue for Rx DMA poll */
+	if (uap->dmarx.poll_rate)
+		dmarx->last_residue = sgbuf->sg.length;
 
 	/*
 	 * Only continue with trying to read the FIFO if all DMA chars have
···
 	writew(uap->dmacr, uap->port.membase + UART011_DMACR);
 }
 
+/*
+ * Timer handler for Rx DMA polling.
+ * Every polling, It checks the residue in the dma buffer and transfer
+ * data to the tty. Also, last_residue is updated for the next polling.
+ */
+static void pl011_dma_rx_poll(unsigned long args)
+{
+	struct uart_amba_port *uap = (struct uart_amba_port *)args;
+	struct tty_port *port = &uap->port.state->port;
+	struct pl011_dmarx_data *dmarx = &uap->dmarx;
+	struct dma_chan *rxchan = uap->dmarx.chan;
+	unsigned long flags = 0;
+	unsigned int dmataken = 0;
+	unsigned int size = 0;
+	struct pl011_sgbuf *sgbuf;
+	int dma_count;
+	struct dma_tx_state state;
+
+	sgbuf = dmarx->use_buf_b ? &uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a;
+	rxchan->device->device_tx_status(rxchan, dmarx->cookie, &state);
+	if (likely(state.residue < dmarx->last_residue)) {
+		dmataken = sgbuf->sg.length - dmarx->last_residue;
+		size = dmarx->last_residue - state.residue;
+		dma_count = tty_insert_flip_string(port, sgbuf->buf + dmataken,
+				size);
+		if (dma_count == size)
+			dmarx->last_residue =  state.residue;
+		dmarx->last_jiffies = jiffies;
+	}
+	tty_flip_buffer_push(port);
+
+	/*
+	 * If no data is received in poll_timeout, the driver will fall back
+	 * to interrupt mode. We will retrigger DMA at the first interrupt.
+	 */
+	if (jiffies_to_msecs(jiffies - dmarx->last_jiffies)
+			> uap->dmarx.poll_timeout) {
+
+		spin_lock_irqsave(&uap->port.lock, flags);
+		pl011_dma_rx_stop(uap);
+		spin_unlock_irqrestore(&uap->port.lock, flags);
+
+		uap->dmarx.running = false;
+		dmaengine_terminate_all(rxchan);
+		del_timer(&uap->dmarx.timer);
+	} else {
+		mod_timer(&uap->dmarx.timer,
+			jiffies + msecs_to_jiffies(uap->dmarx.poll_rate));
+	}
+}
+
 static void pl011_dma_startup(struct uart_amba_port *uap)
 {
 	int ret;
···
 		if (pl011_dma_rx_trigger_dma(uap))
 			dev_dbg(uap->port.dev, "could not trigger initial "
 				"RX DMA job, fall back to interrupt mode\n");
+		if (uap->dmarx.poll_rate) {
+			init_timer(&(uap->dmarx.timer));
+			uap->dmarx.timer.function = pl011_dma_rx_poll;
+			uap->dmarx.timer.data = (unsigned long)uap;
+			mod_timer(&uap->dmarx.timer,
+				jiffies +
+				msecs_to_jiffies(uap->dmarx.poll_rate));
+			uap->dmarx.last_residue = PL011_DMA_BUFFER_SIZE;
+			uap->dmarx.last_jiffies = jiffies;
+		}
 	}
 }
 
···
 		/* Clean up the RX DMA */
 		pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_a, DMA_FROM_DEVICE);
 		pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_b, DMA_FROM_DEVICE);
+		if (uap->dmarx.poll_rate)
+			del_timer_sync(&uap->dmarx.timer);
 		uap->using_rx_dma = false;
 	}
 }
···
 {
 	return uap->using_rx_dma && uap->dmarx.running;
 }
-
 
 #else
 /* Blank functions if the DMA engine is not available */
···
 			dev_dbg(uap->port.dev, "could not trigger RX DMA job "
 				"fall back to interrupt mode again\n");
 			uap->im |= UART011_RXIM;
-		} else
+		} else {
 			uap->im &= ~UART011_RXIM;
+#ifdef CONFIG_DMA_ENGINE
+			/* Start Rx DMA poll */
+			if (uap->dmarx.poll_rate) {
+				uap->dmarx.last_jiffies = jiffies;
+				uap->dmarx.last_residue	= PL011_DMA_BUFFER_SIZE;
+				mod_timer(&uap->dmarx.timer,
+					jiffies +
+					msecs_to_jiffies(uap->dmarx.poll_rate));
+			}
+#endif
+		}
+
 		writew(uap->im, uap->port.membase + UART011_IMSC);
 	}
 	spin_lock(&uap->port.lock);
···
 	unsigned int dummy_read;
 
 	spin_lock_irqsave(&uap->port.lock, flags);
-
 	status = readw(uap->port.membase + UART011_MIS);
 	if (status) {
 		do {
···
 	 */
 	baud = uart_get_baud_rate(port, termios, old, 0,
 				  port->uartclk / clkdiv);
+#ifdef CONFIG_DMA_ENGINE
+	/*
+	 * Adjust RX DMA polling rate with baud rate if not specified.
+	 */
+	if (uap->dmarx.auto_poll_rate)
+		uap->dmarx.poll_rate = DIV_ROUND_UP(10000000, baud);
+#endif
 
 	if (baud > port->uartclk/16)
 		quot = DIV_ROUND_CLOSEST(port->uartclk * 8, baud);
···
 	uap->lcrh_rx = vendor->lcrh_rx;
 	uap->lcrh_tx = vendor->lcrh_tx;
 	uap->old_cr = 0;
-	uap->fifosize = vendor->fifosize;
+	uap->fifosize = vendor->get_fifosize(dev->periphid);
 	uap->port.dev = &dev->dev;
 	uap->port.mapbase = dev->res.start;
 	uap->port.membase = base;

drivers/tty/serial/arc_uart.c

···
 /*
  * Driver internal routine, used by both tty(serial core) as well as tx-isr
  *  -Called under spinlock in either cases
- *  -also tty->stopped / tty->hw_stopped has already been checked
+ *  -also tty->stopped has already been checked
  *     = by uart_start( ) before calling us
  *     = tx_ist checks that too before calling
  */

drivers/tty/serial/bfin_uart.c

···
 }
 #endif
 
-#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
-	defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
-static void bfin_kgdboc_port_shutdown(struct uart_port *port)
-{
-	if (kgdboc_break_enabled) {
-		kgdboc_break_enabled = 0;
-		bfin_serial_shutdown(port);
-	}
-}
-
-static int bfin_kgdboc_port_startup(struct uart_port *port)
-{
-	kgdboc_port_line = port->line;
-	kgdboc_break_enabled = !bfin_serial_startup(port);
-	return 0;
-}
-#endif
-
 static struct uart_ops bfin_serial_pops = {
 	.tx_empty	= bfin_serial_tx_empty,
 	.set_mctrl	= bfin_serial_set_mctrl,
···
 	.request_port	= bfin_serial_request_port,
 	.config_port	= bfin_serial_config_port,
 	.verify_port	= bfin_serial_verify_port,
-#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
-	defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
-	.kgdboc_port_startup	= bfin_kgdboc_port_startup,
-	.kgdboc_port_shutdown	= bfin_kgdboc_port_shutdown,
-#endif
 #ifdef CONFIG_CONSOLE_POLL
 	.poll_put_char	= bfin_serial_poll_put_char,
 	.poll_get_char	= bfin_serial_poll_get_char,

drivers/tty/serial/crisv10.c

···
 
 
 #define DEF_BAUD 115200   /* 115.2 kbit/s */
-#define STD_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)
 #define DEF_RX 0x20  /* or SERIAL_CTRL_W >> 8 */
 /* Default value of tx_ctrl register: has txd(bit 7)=1 (idle) as default */
 #define DEF_TX 0x80  /* or SERIAL_CTRL_B */
···
 	  .ifirstadr   = R_DMA_CH7_FIRST,
 	  .icmdadr     = R_DMA_CH7_CMD,
 	  .idescradr   = R_DMA_CH7_DESCR,
-	  .flags       = STD_FLAGS,
 	  .rx_ctrl     = DEF_RX,
 	  .tx_ctrl     = DEF_TX,
 	  .iseteop     = 2,
···
 	  .ifirstadr   = R_DMA_CH9_FIRST,
 	  .icmdadr     = R_DMA_CH9_CMD,
 	  .idescradr   = R_DMA_CH9_DESCR,
-	  .flags       = STD_FLAGS,
 	  .rx_ctrl     = DEF_RX,
 	  .tx_ctrl     = DEF_TX,
 	  .iseteop     = 3,
···
 	  .ifirstadr   = R_DMA_CH3_FIRST,
 	  .icmdadr     = R_DMA_CH3_CMD,
 	  .idescradr   = R_DMA_CH3_DESCR,
-	  .flags       = STD_FLAGS,
 	  .rx_ctrl     = DEF_RX,
 	  .tx_ctrl     = DEF_TX,
 	  .iseteop     = 0,
···
 	  .ifirstadr   = R_DMA_CH5_FIRST,
 	  .icmdadr     = R_DMA_CH5_CMD,
 	  .idescradr   = R_DMA_CH5_DESCR,
-	  .flags       = STD_FLAGS,
 	  .rx_ctrl     = DEF_RX,
 	  .tx_ctrl     = DEF_TX,
 	  .iseteop     = 1,
···
 
 */
 
-static
-struct e100_serial * handle_ser_rx_interrupt_no_dma(struct e100_serial *info)
+static void handle_ser_rx_interrupt_no_dma(struct e100_serial *info)
 {
 	unsigned long data_read;
 
···
 	}
 
 	tty_flip_buffer_push(&info->port);
-	return info;
 }
 
-static struct e100_serial* handle_ser_rx_interrupt(struct e100_serial *info)
+static void handle_ser_rx_interrupt(struct e100_serial *info)
 {
 	unsigned char rstat;
 
···
 #endif
 /*	DEBUG_LOG(info->line, "ser_interrupt stat %03X\n", rstat | (i << 8)); */
 	if (!info->uses_dma_in) {
-		return handle_ser_rx_interrupt_no_dma(info);
+		handle_ser_rx_interrupt_no_dma(info);
+		return;
 	}
 	/* DMA is used */
 	rstat = info->ioport[REG_STATUS];
···
 	/* Restarting the DMA never hurts */
 	*info->icmdadr = IO_STATE(R_DMA_CH6_CMD, cmd, restart);
 	START_FLUSH_FAST_TIMER(info, "ser_int");
-	return info;
 } /* handle_ser_rx_interrupt */
 
 static void handle_ser_tx_interrupt(struct e100_serial *info)
···
 	}
 	/* Normal char-by-char interrupt */
 	if (info->xmit.head == info->xmit.tail
-	    || info->port.tty->stopped
-	    || info->port.tty->hw_stopped) {
+	    || info->port.tty->stopped) {
 		DFLOW(DEBUG_LOG(info->line, "tx_int: stopped %i\n",
 				info->port.tty->stopped));
 		e100_disable_serial_tx_ready_irq(info);
···
 
 	/* if it was already initialized, skip this */
 
-	if (info->flags & ASYNC_INITIALIZED) {
+	if (info->port.flags & ASYNC_INITIALIZED) {
 		local_irq_restore(flags);
 		free_page(xmit_page);
 		return 0;
···
 
 #endif /* CONFIG_SVINTO_SIM */
 
-	info->flags |= ASYNC_INITIALIZED;
+	info->port.flags |= ASYNC_INITIALIZED;
 
 	local_irq_restore(flags);
 	return 0;
···
 
 #endif /* CONFIG_SVINTO_SIM */
 
-	if (!(info->flags & ASYNC_INITIALIZED))
+	if (!(info->port.flags & ASYNC_INITIALIZED))
 		return;
 
 #ifdef SERIAL_DEBUG_OPEN
···
 	if (info->port.tty)
 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
 
-	info->flags &= ~ASYNC_INITIALIZED;
+	info->port.flags &= ~ASYNC_INITIALIZED;
 	local_irq_restore(flags);
 }
 
···
 	/* possibly, the tx/rx should be disabled first to do this safely */
 
 	/* change baud-rate and write it to the hardware */
-	if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) {
+	if ((info->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) {
 		/* Special baudrate */
 		u32 mask = 0xFF << (info->line*8); /* Each port has 8 bits */
 		unsigned long alt_source =
···
 	if (info->tr_running ||
 	    info->xmit.head == info->xmit.tail ||
 	    tty->stopped ||
-	    tty->hw_stopped ||
 	    !info->xmit.buf)
 		return;
 
···
 
 	if (info->xmit.head != info->xmit.tail &&
 	    !tty->stopped &&
-	    !tty->hw_stopped &&
 	    !info->tr_running) {
 		start_transmit(info);
 	}
···
 	tmp.line = info->line;
 	tmp.port = (int)info->ioport;
 	tmp.irq = info->irq;
-	tmp.flags = info->flags;
+	tmp.flags = info->port.flags;
 	tmp.baud_base = info->baud_base;
-	tmp.close_delay = info->close_delay;
-	tmp.closing_wait = info->closing_wait;
+	tmp.close_delay = info->port.close_delay;
+	tmp.closing_wait = info->port.closing_wait;
 	tmp.custom_divisor = info->custom_divisor;
 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
 		return -EFAULT;
···
 
 	if (!capable(CAP_SYS_ADMIN)) {
 		if ((new_serial.type != info->type) ||
-		    (new_serial.close_delay != info->close_delay) ||
+		    (new_serial.close_delay != info->port.close_delay) ||
 		    ((new_serial.flags & ~ASYNC_USR_MASK) !=
-		     (info->flags & ~ASYNC_USR_MASK)))
+		     (info->port.flags & ~ASYNC_USR_MASK)))
 			return -EPERM;
-		info->flags = ((info->flags & ~ASYNC_USR_MASK) |
+		info->port.flags = ((info->port.flags & ~ASYNC_USR_MASK) |
 			       (new_serial.flags & ASYNC_USR_MASK));
 		goto check_and_exit;
 	}
 
-	if (info->count > 1)
+	if (info->port.count > 1)
 		return -EBUSY;
 
 	/*
···
 	 */
 
 	info->baud_base = new_serial.baud_base;
-	info->flags = ((info->flags & ~ASYNC_FLAGS) |
+	info->port.flags = ((info->port.flags & ~ASYNC_FLAGS) |
 		       (new_serial.flags & ASYNC_FLAGS));
 	info->custom_divisor = new_serial.custom_divisor;
 	info->type = new_serial.type;
-	info->close_delay = new_serial.close_delay;
-	info->closing_wait = new_serial.closing_wait;
-	info->port.low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+	info->port.close_delay = new_serial.close_delay;
+	info->port.closing_wait = new_serial.closing_wait;
+	info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
  check_and_exit:
-	if (info->flags & ASYNC_INITIALIZED) {
+	if (info->port.flags & ASYNC_INITIALIZED) {
 		change_speed(info);
 	} else
 		retval = startup(info);
···
 
 	/* Handle turning off CRTSCTS */
 	if ((old_termios->c_cflag & CRTSCTS) &&
-	    !(tty->termios.c_cflag & CRTSCTS)) {
-		tty->hw_stopped = 0;
+	    !(tty->termios.c_cflag & CRTSCTS))
 		rs_start(tty);
-	}
 
 }
 
···
 	printk("[%d] rs_close ttyS%d, count = %d\n", current->pid,
 	       info->line, info->count);
 #endif
-	if ((tty->count == 1) && (info->count != 1)) {
+	if ((tty->count == 1) && (info->port.count != 1)) {
 		/*
 		 * Uh, oh.  tty->count is 1, which means that the tty
 		 * structure will be freed.  Info->count should always
···
 		 */
 		printk(KERN_ERR
 		       "rs_close: bad serial port count; tty->count is 1, "
-		       "info->count is %d\n", info->count);
-		info->count = 1;
+		       "info->count is %d\n", info->port.count);
+		info->port.count = 1;
 	}
-	if (--info->count < 0) {
+	if (--info->port.count < 0) {
 		printk(KERN_ERR "rs_close: bad serial port count for ttyS%d: %d\n",
-		       info->line, info->count);
-		info->count = 0;
+		       info->line, info->port.count);
+		info->port.count = 0;
 	}
-	if (info->count) {
+	if (info->port.count) {
 		local_irq_restore(flags);
 		return;
 	}
-	info->flags |= ASYNC_CLOSING;
+	info->port.flags |= ASYNC_CLOSING;
 	/*
 	 * Save the termios structure, since this port may have
 	 * separate termios for callout and dialin.
 	 */
-	if (info->flags & ASYNC_NORMAL_ACTIVE)
+	if (info->port.flags & ASYNC_NORMAL_ACTIVE)
 		info->normal_termios = tty->termios;
 	/*
 	 * Now we wait for the transmit buffer to clear; and we notify
 	 * the line discipline to only process XON/XOFF characters.
 	 */
 	tty->closing = 1;
-	if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
-		tty_wait_until_sent(tty, info->closing_wait);
+	if (info->port.closing_wait != ASYNC_CLOSING_WAIT_NONE)
+		tty_wait_until_sent(tty, info->port.closing_wait);
 	/*
 	 * At this point we stop accepting input.  To do this, we
 	 * disable the serial receiver and the DMA receive interrupt.
···
 	e100_disable_rx(info);
 	e100_disable_rx_irq(info);
 
-	if (info->flags & ASYNC_INITIALIZED) {
+	if (info->port.flags & ASYNC_INITIALIZED) {
 		/*
 		 * Before we drop DTR, make sure the UART transmitter
 		 * has completely drained; this is especially
···
 	tty->closing = 0;
 	info->event = 0;
 	info->port.tty = NULL;
-	if (info->blocked_open) {
-		if (info->close_delay)
-			schedule_timeout_interruptible(info->close_delay);
-		wake_up_interruptible(&info->open_wait);
+	if (info->port.blocked_open) {
+		if (info->port.close_delay)
+			schedule_timeout_interruptible(info->port.close_delay);
+		wake_up_interruptible(&info->port.open_wait);
 	}
-	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
-	wake_up_interruptible(&info->close_wait);
+	info->port.flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
+	wake_up_interruptible(&info->port.close_wait);
 	local_irq_restore(flags);
 
 	/* port closed */
···
 	rs_flush_buffer(tty);
 	shutdown(info);
 	info->event = 0;
-	info->count = 0;
-	info->flags &= ~ASYNC_NORMAL_ACTIVE;
+	info->port.count = 0;
+	info->port.flags &= ~ASYNC_NORMAL_ACTIVE;
 	info->port.tty = NULL;
-	wake_up_interruptible(&info->open_wait);
+	wake_up_interruptible(&info->port.open_wait);
 }
 
 /*
···
 	 * until it's done, and then try again.
 	 */
 	if (tty_hung_up_p(filp) ||
-	    (info->flags & ASYNC_CLOSING)) {
-		wait_event_interruptible_tty(tty, info->close_wait,
-			!(info->flags & ASYNC_CLOSING));
+	    (info->port.flags & ASYNC_CLOSING)) {
+		wait_event_interruptible_tty(tty, info->port.close_wait,
+			!(info->port.flags & ASYNC_CLOSING));
 #ifdef SERIAL_DO_RESTART
-		if (info->flags & ASYNC_HUP_NOTIFY)
+		if (info->port.flags & ASYNC_HUP_NOTIFY)
 			return -EAGAIN;
 		else
 			return -ERESTARTSYS;
···
 	 */
 	if ((filp->f_flags & O_NONBLOCK) ||
 	    (tty->flags & (1 << TTY_IO_ERROR))) {
-		info->flags |= ASYNC_NORMAL_ACTIVE;
+		info->port.flags |= ASYNC_NORMAL_ACTIVE;
 		return 0;
 	}
 
···
 	/*
 	 * Block waiting for the carrier detect and the line to become
 	 * free (i.e., not in use by the callout).  While we are in
-	 * this loop, info->count is dropped by one, so that
+	 * this loop, info->port.count is dropped by one, so that
 	 * rs_close() knows when to free things.  We restore it upon
 	 * exit, either normal or abnormal.
 	 */
 	retval = 0;
-	add_wait_queue(&info->open_wait, &wait);
+	add_wait_queue(&info->port.open_wait, &wait);
 #ifdef SERIAL_DEBUG_OPEN
 	printk("block_til_ready before block: ttyS%d, count = %d\n",
-	       info->line, info->count);
+	       info->line, info->port.count);
 #endif
 	local_irq_save(flags);
 	if (!tty_hung_up_p(filp)) {
 		extra_count++;
-		info->count--;
+		info->port.count--;
 	}
 	local_irq_restore(flags);
-	info->blocked_open++;
+	info->port.blocked_open++;
 	while (1) {
 		local_irq_save(flags);
 		/* assert RTS and DTR */
···
 		local_irq_restore(flags);
 		set_current_state(TASK_INTERRUPTIBLE);
 		if (tty_hung_up_p(filp) ||
-		    !(info->flags & ASYNC_INITIALIZED)) {
+		    !(info->port.flags & ASYNC_INITIALIZED)) {
 #ifdef SERIAL_DO_RESTART
-			if (info->flags & ASYNC_HUP_NOTIFY)
+			if (info->port.flags & ASYNC_HUP_NOTIFY)
 				retval = -EAGAIN;
 			else
 				retval = -ERESTARTSYS;
···
 #endif
 			break;
 		}
-		if (!(info->flags & ASYNC_CLOSING) && do_clocal)
+		if (!(info->port.flags & ASYNC_CLOSING) && do_clocal)
 			/* && (do_clocal || DCD_IS_ASSERTED) */
 			break;
 		if (signal_pending(current)) {
···
 		}
 #ifdef SERIAL_DEBUG_OPEN
 		printk("block_til_ready blocking: ttyS%d, count = %d\n",
-		       info->line, info->count);
+		       info->line, info->port.count);
 #endif
 		tty_unlock(tty);
 		schedule();
 		tty_lock(tty);
 	}
 	set_current_state(TASK_RUNNING);
-	remove_wait_queue(&info->open_wait, &wait);
+	remove_wait_queue(&info->port.open_wait, &wait);
 	if (extra_count)
-		info->count++;
-	info->blocked_open--;
+		info->port.count++;
+	info->port.blocked_open--;
 #ifdef SERIAL_DEBUG_OPEN
 	printk("block_til_ready after blocking: ttyS%d, count = %d\n",
-	       info->line, info->count);
+	       info->line, info->port.count);
 #endif
 	if (retval)
 		return retval;
-	info->flags |= ASYNC_NORMAL_ACTIVE;
+	info->port.flags |= ASYNC_NORMAL_ACTIVE;
 	return 0;
 }
 
···
 
 #ifdef SERIAL_DEBUG_OPEN
         printk("[%d] rs_open %s, count = %d\n", current->pid, tty->name,
- 	       info->count);
+ 	       info->port.count);
 #endif
 
-	info->count++;
+	info->port.count++;
 	tty->driver_data = info;
 	info->port.tty = tty;
 
-	info->port.low_latency = !!(info->flags & ASYNC_LOW_LATENCY);
+	info->port.low_latency = !!(info->port.flags & ASYNC_LOW_LATENCY);
 
 	/*
 	 * If the port is in the middle of closing, bail out now
 	 */
 	if (tty_hung_up_p(filp) ||
-	    (info->flags & ASYNC_CLOSING)) {
-		wait_event_interruptible_tty(tty, info->close_wait,
-			!(info->flags & ASYNC_CLOSING));
+	    (info->port.flags & ASYNC_CLOSING)) {
+		wait_event_interruptible_tty(tty, info->port.close_wait,
+			!(info->port.flags & ASYNC_CLOSING));
 #ifdef SERIAL_DO_RESTART
-		return ((info->flags & ASYNC_HUP_NOTIFY) ?
+		return ((info->port.flags & ASYNC_HUP_NOTIFY) ?
 			-EAGAIN : -ERESTARTSYS);
 #else
 		return -EAGAIN;
···
 	/*
 	 * If DMA is enabled try to allocate the irq's.
 	 */
-	if (info->count == 1) {
+	if (info->port.count == 1) {
 		allocated_resources = 1;
 		if (info->dma_in_enabled) {
 			if (request_irq(info->dma_in_irq_nbr,
···
 		if (allocated_resources)
 			deinit_port(info);
 
-		/* FIXME Decrease count info->count here too? */
+		/* FIXME Decrease count info->port.count here too? */
 		return retval;
 	}
 
···
 		return retval;
 	}
 
-	if ((info->count == 1) && (info->flags & ASYNC_SPLIT_TERMIOS)) {
+	if ((info->port.count == 1) && (info->port.flags & ASYNC_SPLIT_TERMIOS)) {
 		tty->termios = info->normal_termios;
 		change_speed(info);
 	}
···
 		if (info->port.tty->stopped)
 			seq_printf(m, " stopped:%i",
 				   (int)info->port.tty->stopped);
-		if (info->port.tty->hw_stopped)
-			seq_printf(m, " hw_stopped:%i",
-				   (int)info->port.tty->hw_stopped);
 	}
 
 	{
···
 		info->forced_eop = 0;
 		info->baud_base = DEF_BAUD_BASE;
 		info->custom_divisor = 0;
-		info->flags = 0;
-		info->close_delay = 5*HZ/10;
-		info->closing_wait = 30*HZ;
 		info->x_char = 0;
 		info->event = 0;
-		info->count = 0;
-		info->blocked_open = 0;
 		info->normal_termios = driver->init_termios;
-		init_waitqueue_head(&info->open_wait);
-		init_waitqueue_head(&info->close_wait);
 		info->xmit.buf = NULL;
 		info->xmit.tail = info->xmit.head = 0;
 		info->first_recv_buffer = info->last_recv_buffer = NULL;

drivers/tty/serial/crisv10.h

···
 	volatile u8 *icmdadr;		/* adr to R_DMA_CHx_CMD */
 	volatile u32 *idescradr;	/* adr to R_DMA_CHx_DESCR */
 
-	int flags;	/* defined in tty.h */
-
 	u8 rx_ctrl;	/* shadow for R_SERIALx_REC_CTRL */
 	u8 tx_ctrl;	/* shadow for R_SERIALx_TR_CTRL */
 	u8 iseteop;	/* bit number for R_SET_EOP for the input dma */
···
 
 	volatile int		tr_running; /* 1 if output is running */
 
-	struct tty_struct	*tty;
-	int			read_status_mask;
-	int			ignore_status_mask;
 	int			x_char;	/* xon/xoff character */
-	int			close_delay;
-	unsigned short		closing_wait;
-	unsigned short		closing_wait2;
 	unsigned long		event;
-	unsigned long		last_active;
 	int			line;
 	int			type;  /* PORT_ETRAX */
-	int			count;	    /* # of fd on device */
-	int			blocked_open; /* # of blocked opens */
 	struct circ_buf		xmit;
 	struct etrax_recv_buffer *first_recv_buffer;
 	struct etrax_recv_buffer *last_recv_buffer;
···
 	struct work_struct	work;
 	struct async_icount	icount;   /* error-statistics etc.*/
 	struct ktermios		normal_termios;
-	struct ktermios		callout_termios;
-	wait_queue_head_t	open_wait;
-	wait_queue_head_t	close_wait;
 
 	unsigned long char_time_usec;       /* The time for 1 char, in usecs */
 	unsigned long flush_time_usec;      /* How often we should flush */

drivers/tty/serial/icom.c

···
 	struct icom_adapter *cur_adapter_entry;
 	struct list_head *tmp;
 
-	icom_adapter = (struct icom_adapter *)
-	    kzalloc(sizeof(struct icom_adapter), GFP_KERNEL);
+	icom_adapter = kzalloc(sizeof(struct icom_adapter), GFP_KERNEL);
 
 	if (!icom_adapter) {
 		return -ENOMEM;

drivers/tty/serial/ifx6x60.c

···
 }
 
 /**
- *	ifx_spi_hangup		-	hang up an IFX device
- *	@ifx_dev: our SPI device
- *
- *	Hang up the tty attached to the IFX device if one is currently
- *	open. If not take no action
- */
-static void ifx_spi_ttyhangup(struct ifx_spi_device *ifx_dev)
-{
-	struct tty_port *pport = &ifx_dev->tty_port;
-	struct tty_struct *tty = tty_port_tty_get(pport);
-	if (tty) {
-		tty_hangup(tty);
-		tty_kref_put(tty);
-	}
-}
-
-/**
  *	ifx_spi_timeout		-	SPI timeout
  *	@arg: our SPI device
  *
···
 	struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *)arg;
 
 	dev_warn(&ifx_dev->spi_dev->dev, "*** SPI Timeout ***");
-	ifx_spi_ttyhangup(ifx_dev);
+	tty_port_tty_hangup(&ifx_dev->tty_port, false);
 	mrdy_set_low(ifx_dev);
 	clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
 }
···
 }
 
 /**
- *	ifx_spi_wakeup_serial	-	SPI space made
- *	@port_data: our SPI device
- *
- *	We have emptied the FIFO enough that we want to get more data
- *	queued into it. Poke the line discipline via tty_wakeup so that
- *	it will feed us more bits
- */
-static void ifx_spi_wakeup_serial(struct ifx_spi_device *ifx_dev)
-{
-	struct tty_struct *tty;
-
-	tty = tty_port_tty_get(&ifx_dev->tty_port);
-	if (!tty)
-		return;
-	tty_wakeup(tty);
-	tty_kref_put(tty);
-}
-
-/**
  *	ifx_spi_prepare_tx_buffer	-	prepare transmit frame
  *	@ifx_dev: our SPI device
  *
···
 			tx_count += temp_count;
 			if (temp_count == queue_length)
 				/* poke port to get more data */
-				ifx_spi_wakeup_serial(ifx_dev);
+				tty_port_tty_wakeup(&ifx_dev->tty_port);
 			else /* more data in port, use next SPI message */
 				ifx_dev->spi_more = 1;
 		}
···
 static void ifx_spi_complete(void *ctx)
 {
 	struct ifx_spi_device *ifx_dev = ctx;
-	struct tty_struct *tty;
-	struct tty_ldisc *ldisc = NULL;
 	int length;
 	int actual_length;
 	unsigned char more;
···
 			 */
 			ifx_spi_power_state_clear(ifx_dev,
 						  IFX_SPI_POWER_DATA_PENDING);
-			tty = tty_port_tty_get(&ifx_dev->tty_port);
-			if (tty) {
-				ldisc = tty_ldisc_ref(tty);
-				if (ldisc) {
-					ldisc->ops->write_wakeup(tty);
-					tty_ldisc_deref(ldisc);
-				}
-				tty_kref_put(tty);
-			}
+			tty_port_tty_wakeup(&ifx_dev->tty_port);
 		}
 	}
 }
···
 		set_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
 		if (!solreset) {
 			/* unsolicited reset  */
-			ifx_spi_ttyhangup(ifx_dev);
+			tty_port_tty_hangup(&ifx_dev->tty_port, false);
 		}
 	} else {
 		/* exited reset */
···
  */
 
 /**
- *	ifx_spi_spi_suspend	-	suspend SPI on system suspend
- *	@dev: device being suspended
- *
- *	Suspend the SPI side. No action needed on Intel MID platforms, may
- *	need extending for other systems.
- */
-static int ifx_spi_spi_suspend(struct spi_device *spi, pm_message_t msg)
-{
-	return 0;
-}
-
-/**
- *	ifx_spi_spi_resume	-	resume SPI side on system resume
- *	@dev: device being suspended
- *
- *	Suspend the SPI side. No action needed on Intel MID platforms, may
- *	need extending for other systems.
- */
-static int ifx_spi_spi_resume(struct spi_device *spi)
-{
-	return 0;
-}
-
-/**
  *	ifx_spi_pm_suspend	-	suspend modem on system suspend
  *	@dev: device being suspended
  *
···
 	.probe = ifx_spi_spi_probe,
 	.shutdown = ifx_spi_spi_shutdown,
 	.remove = ifx_spi_spi_remove,
-	.suspend = ifx_spi_spi_suspend,
-	.resume = ifx_spi_spi_resume,
 	.id_table = ifx_id_table
 };
 

drivers/tty/serial/jsm/jsm_tty.c

···
 
 	jsm_dbg(READ, &ch->ch_bd->pci_dev, "start 2\n");
 
-	if (data_len <= 0) {
-		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
-		jsm_dbg(READ, &ch->ch_bd->pci_dev, "jsm_input 1\n");
-		return;
-	}
-
 	len = tty_buffer_request_room(port, data_len);
 	n = len;
 

drivers/tty/serial/max3100.c

···
 	max3100s[i]->spi = spi;
 	max3100s[i]->irq = spi->irq;
 	spin_lock_init(&max3100s[i]->conf_lock);
-	dev_set_drvdata(&spi->dev, max3100s[i]);
+	spi_set_drvdata(spi, max3100s[i]);
 	pdata = spi->dev.platform_data;
 	max3100s[i]->crystal = pdata->crystal;
 	max3100s[i]->loopback = pdata->loopback;
···
 
 static int max3100_remove(struct spi_device *spi)
 {
-	struct max3100_port *s = dev_get_drvdata(&spi->dev);
+	struct max3100_port *s = spi_get_drvdata(spi);
 	int i;
 
 	mutex_lock(&max3100s_lock);
···
 	return 0;
 }
 
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
 
-static int max3100_suspend(struct spi_device *spi, pm_message_t state)
+static int max3100_suspend(struct device *dev)
 {
-	struct max3100_port *s = dev_get_drvdata(&spi->dev);
+	struct max3100_port *s = dev_get_drvdata(dev);
 
 	dev_dbg(&s->spi->dev, "%s\n", __func__);
 
···
 	return 0;
 }
 
-static int max3100_resume(struct spi_device *spi)
+static int max3100_resume(struct device *dev)
 {
-	struct max3100_port *s = dev_get_drvdata(&spi->dev);
+	struct max3100_port *s = dev_get_drvdata(dev);
 
 	dev_dbg(&s->spi->dev, "%s\n", __func__);
 
···
 	return 0;
 }
 
+static SIMPLE_DEV_PM_OPS(max3100_pm_ops, max3100_suspend, max3100_resume);
+#define MAX3100_PM_OPS (&max3100_pm_ops)
+
 #else
-#define max3100_suspend NULL
-#define max3100_resume  NULL
+#define MAX3100_PM_OPS NULL
 #endif
 
 static struct spi_driver max3100_driver = {
 	.driver = {
 		.name		= "max3100",
 		.owner		= THIS_MODULE,
+		.pm		= MAX3100_PM_OPS,
 	},
-
 	.probe		= max3100_probe,
 	.remove		= max3100_remove,
-	.suspend	= max3100_suspend,
-	.resume		= max3100_resume,
 };
 
 module_spi_driver(max3100_driver);

drivers/tty/serial/max310x.c

···
 	.verify_port	= max310x_verify_port,
 };
 
-static int max310x_suspend(struct spi_device *spi, pm_message_t state)
+#ifdef CONFIG_PM_SLEEP
+
+static int max310x_suspend(struct device *dev)
 {
 	int ret;
-	struct max310x_port *s = dev_get_drvdata(&spi->dev);
+	struct max310x_port *s = dev_get_drvdata(dev);
 
-	dev_dbg(&spi->dev, "Suspend\n");
+	dev_dbg(dev, "Suspend\n");
 
 	ret = uart_suspend_port(&s->uart, &s->port);
 
···
 	return ret;
 }
 
-static int max310x_resume(struct spi_device *spi)
+static int max310x_resume(struct device *dev)
 {
-	struct max310x_port *s = dev_get_drvdata(&spi->dev);
+	struct max310x_port *s = dev_get_drvdata(dev);
 
-	dev_dbg(&spi->dev, "Resume\n");
+	dev_dbg(dev, "Resume\n");
 
 	if (s->pdata->suspend)
 		s->pdata->suspend(0);
···
 
 	return uart_resume_port(&s->uart, &s->port);
 }
+
+static SIMPLE_DEV_PM_OPS(max310x_pm_ops, max310x_suspend, max310x_resume);
+#define MAX310X_PM_OPS (&max310x_pm_ops)
+
+#else
+#define MAX310X_PM_OPS NULL
+#endif
 
 #ifdef CONFIG_GPIOLIB
 static int max310x_gpio_get(struct gpio_chip *chip, unsigned offset)
···
 	.driver = {
 		.name	= "max310x",
 		.owner	= THIS_MODULE,
+		.pm	= MAX310X_PM_OPS,
 	},
 	.probe		= max310x_probe,
 	.remove		= max310x_remove,
-	.suspend	= max310x_suspend,
-	.resume		= max310x_resume,
 	.id_table	= max310x_id_table,
 };
 module_spi_driver(max310x_driver);

drivers/tty/serial/mrst_max3110.c

···
 	.cons		= &serial_m3110_console,
 };
 
-#ifdef CONFIG_PM
-static int serial_m3110_suspend(struct spi_device *spi, pm_message_t state)
+#ifdef CONFIG_PM_SLEEP
+static int serial_m3110_suspend(struct device *dev)
 {
+	struct spi_device *spi = to_spi_device(dev);
 	struct uart_max3110 *max = spi_get_drvdata(spi);
 
 	disable_irq(max->irq);
···
 	return 0;
 }
 
-static int serial_m3110_resume(struct spi_device *spi)
+static int serial_m3110_resume(struct device *dev)
 {
+	struct spi_device *spi = to_spi_device(dev);
 	struct uart_max3110 *max = spi_get_drvdata(spi);
 
 	max3110_out(max, max->cur_conf);
···
 	enable_irq(max->irq);
 	return 0;
 }
+
+static SIMPLE_DEV_PM_OPS(serial_m3110_pm_ops, serial_m3110_suspend,
+			serial_m3110_resume);
+#define SERIAL_M3110_PM_OPS (&serial_m3110_pm_ops)
+
 #else
-#define serial_m3110_suspend	NULL
-#define serial_m3110_resume	NULL
+#define SERIAL_M3110_PM_OPS NULL
 #endif
 
 static int serial_m3110_probe(struct spi_device *spi)
···
 	.driver = {
 			.name	= "spi_max3111",
 			.owner	= THIS_MODULE,
+			.pm	= SERIAL_M3110_PM_OPS,
 	},
 	.probe		= serial_m3110_probe,
 	.remove		= serial_m3110_remove,
-	.suspend	= serial_m3110_suspend,
-	.resume		= serial_m3110_resume,
 };
 
 static int __init serial_m3110_init(void)

drivers/tty/serial/msm_serial_hs.c

···
 	unsigned int error_f = 0;
 	unsigned long flags;
 	unsigned int flush;
-	struct tty_struct *tty;
 	struct tty_port *port;
 	struct uart_port *uport;
 	struct msm_hs_port *msm_uport;
···
 	clk_enable(msm_uport->clk);
 
 	port = &uport->state->port;
-	tty = port->tty;
 
 	msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_DISABLE);
 

drivers/tty/serial/msm_smd_tty.c

···
 
 static int smd_tty_port_activate(struct tty_port *tport, struct tty_struct *tty)
 {
+	struct smd_tty_info *info = container_of(tport, struct smd_tty_info,
+			port);
 	int i, res = 0;
-	int n = tty->index;
 	const char *name = NULL;
-	struct smd_tty_info *info = smd_tty + n;
 
 	for (i = 0; i < smd_tty_channels_len; i++) {
-		if (smd_tty_channels[i].id == n) {
+		if (smd_tty_channels[i].id == tty->index) {
 			name = smd_tty_channels[i].name;
 			break;
 		}
···
 
 static void smd_tty_port_shutdown(struct tty_port *tport)
 {
-	struct smd_tty_info *info;
-	struct tty_struct *tty = tty_port_tty_get(tport);
+	struct smd_tty_info *info = container_of(tport, struct smd_tty_info,
+			port);
 
-	info = tty->driver_data;
 	if (info->ch) {
 		smd_close(info->ch);
 		info->ch = 0;
 	}
-
-	tty->driver_data = 0;
-	tty_kref_put(tty);
 }
 
 static int smd_tty_open(struct tty_struct *tty, struct file *f)

drivers/tty/serial/mxs-auart.c

···
 	unsigned int old_ctrl0, old_ctrl2;
 	unsigned int to = 1000;
 
-	if (co->index >	MXS_AUART_PORTS || co->index < 0)
+	if (co->index >= MXS_AUART_PORTS || co->index < 0)
 		return;
 
 	s = auart_port[co->index];
···
 	s->port.fifosize = 16;
 	s->port.uartclk = clk_get_rate(s->clk);
 	s->port.type = PORT_IMX;
-	s->port.dev = s->dev = get_device(&pdev->dev);
+	s->port.dev = s->dev = &pdev->dev;
 
 	s->ctrl = 0;
 
···
 	auart_port[pdev->id] = NULL;
 	free_irq(s->irq, s);
 out_free_clk:
-	put_device(s->dev);
 	clk_put(s->clk);
 out_free:
 	kfree(s);
···
 
 	auart_port[pdev->id] = NULL;
 
-	put_device(s->dev);
 	clk_put(s->clk);
 	free_irq(s->irq, s);
 	kfree(s);

drivers/tty/serial/of_serial.c

···
 #include <linux/slab.h>
 #include <linux/delay.h>
 #include <linux/serial_core.h>
-#include <linux/serial_8250.h>
 #include <linux/serial_reg.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
 #include <linux/nwpserial.h>
 #include <linux/clk.h>
+
+#include "8250/8250.h"
 
 struct of_serial_info {
 	struct clk *clk;
···
 	if (of_property_read_u32(np, "reg-shift", &prop) == 0)
 		port->regshift = prop;
 
+	/* Check for fifo size */
+	if (of_property_read_u32(np, "fifo-size", &prop) == 0)
+		port->fifosize = prop;
+
 	port->irq = irq_of_parse_and_map(np, 0);
 	port->iotype = UPIO_MEM;
 	if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
···
 #ifdef CONFIG_SERIAL_8250
 	case PORT_8250 ... PORT_MAX_8250:
 	{
-		/* For now the of bindings don't support the extra
-		   8250 specific bits */
 		struct uart_8250_port port8250;
 		memset(&port8250, 0, sizeof(port8250));
 		port8250.port = port;
+
+		if (port.fifosize)
+			port8250.capabilities = UART_CAP_FIFO;
+
+		if (of_property_read_bool(ofdev->dev.of_node,
+					  "auto-flow-control"))
+			port8250.capabilities |= UART_CAP_AFE;
+
 		ret = serial8250_register_8250_port(&port8250);
 		break;
 	}

drivers/tty/serial/pch_uart.c

···
 	return 0;
 }
 
-static struct uart_ops pch_uart_ops = {
-	.tx_empty = pch_uart_tx_empty,
-	.set_mctrl = pch_uart_set_mctrl,
-	.get_mctrl = pch_uart_get_mctrl,
-	.stop_tx = pch_uart_stop_tx,
-	.start_tx = pch_uart_start_tx,
-	.stop_rx = pch_uart_stop_rx,
-	.enable_ms = pch_uart_enable_ms,
-	.break_ctl = pch_uart_break_ctl,
-	.startup = pch_uart_startup,
-	.shutdown = pch_uart_shutdown,
-	.set_termios = pch_uart_set_termios,
-/*	.pm		= pch_uart_pm,		Not supported yet */
-/*	.set_wake	= pch_uart_set_wake,	Not supported yet */
-	.type = pch_uart_type,
-	.release_port = pch_uart_release_port,
-	.request_port = pch_uart_request_port,
-	.config_port = pch_uart_config_port,
-	.verify_port = pch_uart_verify_port
-};
-
-#ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
-
 /*
  *	Wait for transmitter & holding register to empty
  */
···
 		}
 	}
 }
+
+#ifdef CONFIG_CONSOLE_POLL
+/*
+ * Console polling routines for communicate via uart while
+ * in an interrupt or debug context.
+ */
+static int pch_uart_get_poll_char(struct uart_port *port)
+{
+	struct eg20t_port *priv =
+		container_of(port, struct eg20t_port, port);
+	u8 lsr = ioread8(priv->membase + UART_LSR);
+
+	if (!(lsr & UART_LSR_DR))
+		return NO_POLL_CHAR;
+
+	return ioread8(priv->membase + PCH_UART_RBR);
+}
+
+
+static void pch_uart_put_poll_char(struct uart_port *port,
+			 unsigned char c)
+{
+	unsigned int ier;
+	struct eg20t_port *priv =
+		container_of(port, struct eg20t_port, port);
+
+	/*
+	 * First save the IER then disable the interrupts
+	 */
+	ier = ioread8(priv->membase + UART_IER);
+	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_ALL_INT);
+
+	wait_for_xmitr(priv, UART_LSR_THRE);
+	/*
+	 * Send the character out.
+	 * If a LF, also do CR...
+	 */
+	iowrite8(c, priv->membase + PCH_UART_THR);
+	if (c == 10) {
+		wait_for_xmitr(priv, UART_LSR_THRE);
+		iowrite8(13, priv->membase + PCH_UART_THR);
+	}
+
+	/*
+	 * Finally, wait for transmitter to become empty
+	 * and restore the IER
+	 */
+	wait_for_xmitr(priv, BOTH_EMPTY);
+	iowrite8(ier, priv->membase + UART_IER);
+}
+#endif /* CONFIG_CONSOLE_POLL */
+
+static struct uart_ops pch_uart_ops = {
+	.tx_empty = pch_uart_tx_empty,
+	.set_mctrl = pch_uart_set_mctrl,
+	.get_mctrl = pch_uart_get_mctrl,
+	.stop_tx = pch_uart_stop_tx,
+	.start_tx = pch_uart_start_tx,
+	.stop_rx = pch_uart_stop_rx,
+	.enable_ms = pch_uart_enable_ms,
+	.break_ctl = pch_uart_break_ctl,
+	.startup = pch_uart_startup,
+	.shutdown = pch_uart_shutdown,
+	.set_termios = pch_uart_set_termios,
+/*	.pm		= pch_uart_pm,		Not supported yet */
+/*	.set_wake	= pch_uart_set_wake,	Not supported yet */
+	.type = pch_uart_type,
+	.release_port = pch_uart_release_port,
+	.request_port = pch_uart_request_port,
+	.config_port = pch_uart_config_port,
+	.verify_port = pch_uart_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+	.poll_get_char = pch_uart_get_poll_char,
+	.poll_put_char = pch_uart_put_poll_char,
+#endif
+};
+
+#ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
 
 static void pch_console_putchar(struct uart_port *port, int ch)
 {
···
 #define PCH_CONSOLE	(&pch_console)
 #else
 #define PCH_CONSOLE	NULL
-#endif
+#endif	/* CONFIG_SERIAL_PCH_UART_CONSOLE */
 
 static struct uart_driver pch_uart_driver = {
 	.owner = THIS_MODULE,

drivers/tty/serial/samsung.c

···
 #include <linux/tty_flip.h>
 #include <linux/serial_core.h>
 #include <linux/serial.h>
+#include <linux/serial_s3c.h>
 #include <linux/delay.h>
 #include <linux/clk.h>
 #include <linux/cpufreq.h>
···
 
 #include <asm/irq.h>
 
-#include <mach/hardware.h>
-
-#include <plat/regs-serial.h>
+#ifdef CONFIG_SAMSUNG_CLOCK
 #include <plat/clock.h>
+#endif
 
 #include "samsung.h"
 
···
 
 	/* Clear pending interrupts and mask all interrupts */
 	if (s3c24xx_serial_has_interrupt_mask(port)) {
+		free_irq(port->irq, ourport);
+
 		wr_regl(port, S3C64XX_UINTP, 0xf);
 		wr_regl(port, S3C64XX_UINTM, 0xf);
 	}
···
 
 	dbg("s3c64xx_serial_startup: port=%p (%08lx,%p)\n",
 	    port->mapbase, port->membase);
+
+	wr_regl(port, S3C64XX_UINTM, 0xf);
 
 	ret = request_irq(port->irq, s3c64xx_serial_handle_irq, IRQF_SHARED,
 			  s3c24xx_serial_portname(port), ourport);
···
 #define S3C24XX_SERIAL_CONSOLE NULL
 #endif
 
-#ifdef CONFIG_CONSOLE_POLL
+#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
 static int s3c24xx_serial_get_poll_char(struct uart_port *port);
 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
 			 unsigned char c);
···
 	.request_port	= s3c24xx_serial_request_port,
 	.config_port	= s3c24xx_serial_config_port,
 	.verify_port	= s3c24xx_serial_verify_port,
-#ifdef CONFIG_CONSOLE_POLL
+#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
 	.poll_get_char = s3c24xx_serial_get_poll_char,
 	.poll_put_char = s3c24xx_serial_put_poll_char,
 #endif
···
 	return 0;
 }
 
+#ifdef CONFIG_SAMSUNG_CLOCK
 static ssize_t s3c24xx_serial_show_clksrc(struct device *dev,
 					  struct device_attribute *attr,
 					  char *buf)
···
 }
 
 static DEVICE_ATTR(clock_source, S_IRUGO, s3c24xx_serial_show_clksrc, NULL);
-
+#endif
 
 /* Device driver serial port probe */
 
···
 	uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
 	platform_set_drvdata(pdev, &ourport->port);
 
+#ifdef CONFIG_SAMSUNG_CLOCK
 	ret = device_create_file(&pdev->dev, &dev_attr_clock_source);
 	if (ret < 0)
 		dev_err(&pdev->dev, "failed to add clock source attr.\n");
+#endif
 
 	ret = s3c24xx_serial_cpufreq_register(ourport);
 	if (ret < 0)
···
 
 	if (port) {
 		s3c24xx_serial_cpufreq_deregister(to_ourport(port));
+#ifdef CONFIG_SAMSUNG_CLOCK
 		device_remove_file(&dev->dev, &dev_attr_clock_source);
+#endif
 		uart_remove_one_port(&s3c24xx_uart_drv, port);
 	}
 
···
 	return 0;
 }
 
+static int s3c24xx_serial_resume_noirq(struct device *dev)
+{
+	struct uart_port *port = s3c24xx_dev_to_port(dev);
+
+	if (port) {
+		/* restore IRQ mask */
+		if (s3c24xx_serial_has_interrupt_mask(port)) {
+			unsigned int uintm = 0xf;
+			if (tx_enabled(port))
+				uintm &= ~S3C64XX_UINTM_TXD_MSK;
+			if (rx_enabled(port))
+				uintm &= ~S3C64XX_UINTM_RXD_MSK;
+			wr_regl(port, S3C64XX_UINTM, uintm);
+		}
+	}
+
+	return 0;
+}
+
 static const struct dev_pm_ops s3c24xx_serial_pm_ops = {
 	.suspend = s3c24xx_serial_suspend,
 	.resume = s3c24xx_serial_resume,
+	.resume_noirq = s3c24xx_serial_resume_noirq,
 };
 #define SERIAL_SAMSUNG_PM_OPS	(&s3c24xx_serial_pm_ops)
 
···
 	return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
 }
 
+static bool
+s3c24xx_port_configured(unsigned int ucon)
+{
+	/* consider the serial port configured if the tx/rx mode set */
+	return (ucon & 0xf) != 0;
+}
+
 #ifdef CONFIG_CONSOLE_POLL
 /*
  * Console polling routines for writing and reading from the uart while
···
 		unsigned char c)
 {
 	unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON);
+	unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
+
+	/* not possible to xmit on unconfigured port */
+	if (!s3c24xx_port_configured(ucon))
+		return;
 
 	while (!s3c24xx_serial_console_txrdy(port, ufcon))
 		cpu_relax();
···
 s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
 {
 	unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON);
+	unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
+
+	/* not possible to xmit on unconfigured port */
+	if (!s3c24xx_port_configured(ucon))
+		return;
+
 	while (!s3c24xx_serial_console_txrdy(port, ufcon))
 		barrier();
 	wr_regb(cons_uart, S3C2410_UTXH, ch);
···
 	    "registers: ulcon=%08x, ucon=%08x, ubdriv=%08x\n",
 	    port, ulcon, ucon, ubrdiv);
 
-	if ((ucon & 0xf) != 0) {
-		/* consider the serial port configured if the tx/rx mode set */
-
+	if (s3c24xx_port_configured(ucon)) {
 		switch (ulcon & S3C2410_LCON_CSMASK) {
 		case S3C2410_LCON_CS5:
 			*bits = 5;

drivers/tty/serial/samsung.h

···
 #define wr_regb(port, reg, val) __raw_writeb(val, portaddr(port, reg))
 #define wr_regl(port, reg, val) __raw_writel(val, portaddr(port, reg))
 
-#ifdef CONFIG_SERIAL_SAMSUNG_DEBUG
+#if defined(CONFIG_SERIAL_SAMSUNG_DEBUG) && \
+    defined(CONFIG_DEBUG_LL) && \
+    !defined(MODULE)
 
 extern void printascii(const char *);
 

drivers/tty/serial/sccnxp.c

···
 #include <linux/spinlock.h>
 #include <linux/platform_device.h>
 #include <linux/platform_data/serial-sccnxp.h>
+#include <linux/regulator/consumer.h>
 
 #define SCCNXP_NAME			"uart-sccnxp"
 #define SCCNXP_MAJOR			204
···
 	struct timer_list	timer;
 
 	struct sccnxp_pdata	pdata;
+
+	struct regulator	*regulator;
 };
 
 static inline u8 sccnxp_raw_read(void __iomem *base, u8 reg, u8 shift)
···
 		return -EADDRNOTAVAIL;
 	}
 
-	dev_set_name(&pdev->dev, SCCNXP_NAME);
-
 	s = devm_kzalloc(&pdev->dev, sizeof(struct sccnxp_port), GFP_KERNEL);
 	if (!s) {
 		dev_err(&pdev->dev, "Error allocating port structure\n");
···
 		goto err_out;
 	}
 
+	s->regulator = devm_regulator_get(&pdev->dev, "VCC");
+	if (!IS_ERR(s->regulator)) {
+		ret = regulator_enable(s->regulator);
+		if (ret) {
+			dev_err(&pdev->dev,
+				"Failed to enable regulator: %i\n", ret);
+			return ret;
+		}
+	}
+
 	membase = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(membase)) {
 		ret = PTR_ERR(membase);
···
 	s->imr = 0;
 	sccnxp_write(&s->port[0], SCCNXP_IMR_REG, 0);
 
-	/* Board specific configure */
-	if (s->pdata.init)
-		s->pdata.init();
-
 	if (!s->poll) {
 		ret = devm_request_threaded_irq(&pdev->dev, s->irq, NULL,
 						sccnxp_ist,
···
 	uart_unregister_driver(&s->uart);
 	platform_set_drvdata(pdev, NULL);
 
-	if (s->pdata.exit)
-		s->pdata.exit();
+	if (!IS_ERR(s->regulator))
+		return regulator_disable(s->regulator);
 
 	return 0;
 }

drivers/tty/serial/serial-tegra.c

···
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
 #include <linux/dmapool.h>
+#include <linux/err.h>
 #include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/module.h>
···
 	}
 
 	u->mapbase = resource->start;
-	u->membase = devm_request_and_ioremap(&pdev->dev, resource);
-	if (!u->membase) {
-		dev_err(&pdev->dev, "memregion/iomap address req failed\n");
-		return -EADDRNOTAVAIL;
-	}
+	u->membase = devm_ioremap_resource(&pdev->dev, resource);
+	if (IS_ERR(u->membase))
+		return PTR_ERR(u->membase);
 
 	tup->uart_clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(tup->uart_clk)) {

drivers/tty/serial/serial_core.c

···
 		mutex_unlock(&port->mutex);
 		return 0;
 	}
+	put_device(tty_dev);
+
 	if (console_suspend_enabled || !uart_console(uport))
 		uport->suspended = 1;
 
···
 			disable_irq_wake(uport->irq);
 			uport->irq_wake = 0;
 		}
+		put_device(tty_dev);
 		mutex_unlock(&port->mutex);
 		return 0;
 	}
+	put_device(tty_dev);
 	uport->suspended = 0;
 
 	/*

drivers/tty/serial/sh-sci.h

···
     defined(CONFIG_CPU_SUBTYPE_SH7720) || \
     defined(CONFIG_CPU_SUBTYPE_SH7721) || \
     defined(CONFIG_ARCH_SH73A0) || \
-    defined(CONFIG_ARCH_SH7367) || \
-    defined(CONFIG_ARCH_SH7377) || \
     defined(CONFIG_ARCH_SH7372) || \
     defined(CONFIG_ARCH_R8A7740)
 

drivers/tty/serial/sirfsoc_uart.c

···
 	{ .compatible = "sirf,marco-uart", },
 	{}
 };
-MODULE_DEVICE_TABLE(of, sirfsoc_serial_of_match);
+MODULE_DEVICE_TABLE(of, sirfsoc_uart_ids);
 
 static struct platform_driver sirfsoc_uart_driver = {
 	.probe		= sirfsoc_uart_probe,

drivers/tty/serial/sunsab.c

···
 				flag = TTY_FRAME;
 		}
 
-		if (uart_handle_sysrq_char(&up->port, ch))
+		if (uart_handle_sysrq_char(&up->port, ch) || !port)
 			continue;
 
 		if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&

drivers/tty/serial/sunzilog.c

···
 			else if (r1 & CRC_ERR)
 				flag = TTY_FRAME;
 		}
-		if (uart_handle_sysrq_char(&up->port, ch))
+		if (uart_handle_sysrq_char(&up->port, ch) || !port)
 			continue;
 
 		if (up->port.ignore_status_mask == 0xff ||

drivers/tty/serial/vt8500_serial.c

···
 #include <linux/clk.h>
 #include <linux/platform_device.h>
 #include <linux/of.h>
+#include <linux/err.h>
 
 /*
  * UART Register offsets
···
 	if (!vt8500_port)
 		return -ENOMEM;
 
-	vt8500_port->uart.membase = devm_request_and_ioremap(&pdev->dev, mmres);
-	if (!vt8500_port->uart.membase)
-		return -EADDRNOTAVAIL;
+	vt8500_port->uart.membase = devm_ioremap_resource(&pdev->dev, mmres);
+	if (IS_ERR(vt8500_port->uart.membase))
+		return PTR_ERR(vt8500_port->uart.membase);
 
 	vt8500_port->clk = of_clk_get(pdev->dev.of_node, 0);
 	if (IS_ERR(vt8500_port->clk)) {

drivers/tty/serial/xilinx_uartps.c

···
 	xuartps_writel(XUARTPS_IXR_TXEMPTY | XUARTPS_IXR_PARITY |
 		XUARTPS_IXR_FRAMING | XUARTPS_IXR_OVERRUN |
 		XUARTPS_IXR_RXTRIG | XUARTPS_IXR_TOUT, XUARTPS_IER_OFFSET);
-	xuartps_writel(~(XUARTPS_IXR_TXEMPTY | XUARTPS_IXR_PARITY |
-		XUARTPS_IXR_FRAMING | XUARTPS_IXR_OVERRUN |
-		XUARTPS_IXR_RXTRIG | XUARTPS_IXR_TOUT), XUARTPS_IDR_OFFSET);
 
 	return retval;
 }

drivers/tty/synclink.c

···
 		container_of(work, struct mgsl_struct, task);
 	int action;
 
-	if (!info)
-		return;
-		
 	if ( debug_level >= DEBUG_LEVEL_BH )
 		printk( "%s(%d):mgsl_bh_handler(%s) entry\n",
 			__FILE__,__LINE__,info->device_name);
···
 	port->blocked_open++;
 	
 	while (1) {
-		if (tty->termios.c_cflag & CBAUD)
+		if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
 			tty_port_raise_dtr_rts(port);
 		
 		set_current_state(TASK_INTERRUPTIBLE);

drivers/tty/synclink_gt.c

···
 	port->blocked_open++;
 
 	while (1) {
-		if ((tty->termios.c_cflag & CBAUD))
+		if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
 			tty_port_raise_dtr_rts(port);
 
 		set_current_state(TASK_INTERRUPTIBLE);

drivers/tty/synclinkmp.c

···
 	port->blocked_open++;
 
 	while (1) {
-		if (tty->termios.c_cflag & CBAUD)
+		if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
 			tty_port_raise_dtr_rts(port);
 
 		set_current_state(TASK_INTERRUPTIBLE);

drivers/tty/sysrq.c

···
 }
 static struct sysrq_key_op sysrq_SAK_op = {
 	.handler	= sysrq_handle_SAK,
-	.help_msg	= "saK",
+	.help_msg	= "sak(k)",
 	.action_msg	= "SAK",
 	.enable_mask	= SYSRQ_ENABLE_KEYBOARD,
 };
···
 
 static struct sysrq_key_op sysrq_unraw_op = {
 	.handler	= sysrq_handle_unraw,
-	.help_msg	= "unRaw",
+	.help_msg	= "unraw(r)",
 	.action_msg	= "Keyboard mode set to system default",
 	.enable_mask	= SYSRQ_ENABLE_KEYBOARD,
 };
···
 }
 static struct sysrq_key_op sysrq_crash_op = {
 	.handler	= sysrq_handle_crash,
-	.help_msg	= "Crash",
+	.help_msg	= "crash(c)",
 	.action_msg	= "Trigger a crash",
 	.enable_mask	= SYSRQ_ENABLE_DUMP,
 };
···
 }
 static struct sysrq_key_op sysrq_reboot_op = {
 	.handler	= sysrq_handle_reboot,
-	.help_msg	= "reBoot",
+	.help_msg	= "reboot(b)",
 	.action_msg	= "Resetting",
 	.enable_mask	= SYSRQ_ENABLE_BOOT,
 };
···
 }
 static struct sysrq_key_op sysrq_sync_op = {
 	.handler	= sysrq_handle_sync,
-	.help_msg	= "Sync",
+	.help_msg	= "sync(s)",
 	.action_msg	= "Emergency Sync",
 	.enable_mask	= SYSRQ_ENABLE_SYNC,
 };
···
 
 static struct sysrq_key_op sysrq_show_timers_op = {
 	.handler	= sysrq_handle_show_timers,
-	.help_msg	= "show-all-timers(Q)",
+	.help_msg	= "show-all-timers(q)",
 	.action_msg	= "Show clockevent devices & pending hrtimers (no others)",
 };
 
···
 }
 static struct sysrq_key_op sysrq_mountro_op = {
 	.handler	= sysrq_handle_mountro,
-	.help_msg	= "Unmount",
+	.help_msg	= "unmount(u)",
 	.action_msg	= "Emergency Remount R/O",
 	.enable_mask	= SYSRQ_ENABLE_REMOUNT,
 };
···
 
 static struct sysrq_key_op sysrq_showlocks_op = {
 	.handler	= sysrq_handle_showlocks,
-	.help_msg	= "show-all-locks(D)",
+	.help_msg	= "show-all-locks(d)",
 	.action_msg	= "Show Locks Held",
 };
 #else
···
 
 static struct sysrq_key_op sysrq_showallcpus_op = {
 	.handler	= sysrq_handle_showallcpus,
-	.help_msg	= "show-backtrace-all-active-cpus(L)",
+	.help_msg	= "show-backtrace-all-active-cpus(l)",
 	.action_msg	= "Show backtrace of all active CPUs",
 	.enable_mask	= SYSRQ_ENABLE_DUMP,
 };
···
 }
 static struct sysrq_key_op sysrq_showregs_op = {
 	.handler	= sysrq_handle_showregs,
-	.help_msg	= "show-registers(P)",
+	.help_msg	= "show-registers(p)",
 	.action_msg	= "Show Regs",
 	.enable_mask	= SYSRQ_ENABLE_DUMP,
 };
···
 }
 static struct sysrq_key_op sysrq_showstate_op = {
 	.handler	= sysrq_handle_showstate,
-	.help_msg	= "show-task-states(T)",
+	.help_msg	= "show-task-states(t)",
 	.action_msg	= "Show State",
 	.enable_mask	= SYSRQ_ENABLE_DUMP,
 };
···
 }
 static struct sysrq_key_op sysrq_showstate_blocked_op = {
 	.handler	= sysrq_handle_showstate_blocked,
-	.help_msg	= "show-blocked-tasks(W)",
+	.help_msg	= "show-blocked-tasks(w)",
 	.action_msg	= "Show Blocked State",
 	.enable_mask	= SYSRQ_ENABLE_DUMP,
 };
···
 }
 static struct sysrq_key_op sysrq_ftrace_dump_op = {
 	.handler	= sysrq_ftrace_dump,
-	.help_msg	= "dump-ftrace-buffer(Z)",
+	.help_msg	= "dump-ftrace-buffer(z)",
 	.action_msg	= "Dump ftrace buffer",
 	.enable_mask	= SYSRQ_ENABLE_DUMP,
 };
···
 }
 static struct sysrq_key_op sysrq_showmem_op = {
 	.handler	= sysrq_handle_showmem,
-	.help_msg	= "show-memory-usage(M)",
+	.help_msg	= "show-memory-usage(m)",
 	.action_msg	= "Show Memory",
 	.enable_mask	= SYSRQ_ENABLE_DUMP,
 };
···
 }
 static struct sysrq_key_op sysrq_term_op = {
 	.handler	= sysrq_handle_term,
-	.help_msg	= "terminate-all-tasks(E)",
+	.help_msg	= "terminate-all-tasks(e)",
 	.action_msg	= "Terminate All Tasks",
 	.enable_mask	= SYSRQ_ENABLE_SIGNAL,
 };
···
 }
 static struct sysrq_key_op sysrq_moom_op = {
 	.handler	= sysrq_handle_moom,
-	.help_msg	= "memory-full-oom-kill(F)",
+	.help_msg	= "memory-full-oom-kill(f)",
 	.action_msg	= "Manual OOM execution",
 	.enable_mask	= SYSRQ_ENABLE_SIGNAL,
 };
···
 }
 static struct sysrq_key_op sysrq_thaw_op = {
 	.handler	= sysrq_handle_thaw,
-	.help_msg	= "thaw-filesystems(J)",
+	.help_msg	= "thaw-filesystems(j)",
 	.action_msg	= "Emergency Thaw of all frozen filesystems",
 	.enable_mask	= SYSRQ_ENABLE_SIGNAL,
 };
···
 }
 static struct sysrq_key_op sysrq_kill_op = {
 	.handler	= sysrq_handle_kill,
-	.help_msg	= "kill-all-tasks(I)",
+	.help_msg	= "kill-all-tasks(i)",
 	.action_msg	= "Kill All Tasks",
 	.enable_mask	= SYSRQ_ENABLE_SIGNAL,
 };
···
 }
 static struct sysrq_key_op sysrq_unrt_op = {
 	.handler	= sysrq_handle_unrt,
-	.help_msg	= "nice-all-RT-tasks(N)",
+	.help_msg	= "nice-all-RT-tasks(n)",
 	.action_msg	= "Nice All RT Tasks",
 	.enable_mask	= SYSRQ_ENABLE_RTNICE,
 };

drivers/tty/tty_buffer.c

···
 				tty_buffer_free(port, head);
 				continue;
 			}
-			/* Ldisc or user is trying to flush the buffers
-			   we are feeding to the ldisc, stop feeding the
-			   line discipline as we want to empty the queue */
-			if (test_bit(TTYP_FLUSHPENDING, &port->iflags))
-				break;
 			if (!tty->receive_room)
 				break;
 			if (count > tty->receive_room)
···
 			disc->ops->receive_buf(tty, char_buf,
 							flag_buf, count);
 			spin_lock_irqsave(&buf->lock, flags);
+			/* Ldisc or user is trying to flush the buffers.
+			   We may have a deferred request to flush the
+			   input buffer, if so pull the chain under the lock
+			   and empty the queue */
+			if (test_bit(TTYP_FLUSHPENDING, &port->iflags)) {
+				__tty_buffer_flush(port);
+				clear_bit(TTYP_FLUSHPENDING, &port->iflags);
+				wake_up(&tty->read_wait);
+				break;
+			}
 		}
 		clear_bit(TTYP_FLUSHING, &port->iflags);
 	}
 
-	/* We may have a deferred request to flush the input buffer,
-	   if so pull the chain under the lock and empty the queue */
-	if (test_bit(TTYP_FLUSHPENDING, &port->iflags)) {
-		__tty_buffer_flush(port);
-		clear_bit(TTYP_FLUSHPENDING, &port->iflags);
-		wake_up(&tty->read_wait);
-	}
 	spin_unlock_irqrestore(&buf->lock, flags);
 
 	tty_ldisc_deref(disc);

drivers/tty/tty_io.c

···
 EXPORT_SYMBOL_GPL(tty_wakeup);
 
 /**
+ *	tty_signal_session_leader	- sends SIGHUP to session leader
+ *	@tty		controlling tty
+ *	@exit_session	if non-zero, signal all foreground group processes
+ *
+ *	Send SIGHUP and SIGCONT to the session leader and its process group.
+ *	Optionally, signal all processes in the foreground process group.
+ *
+ *	Returns the number of processes in the session with this tty
+ *	as their controlling terminal. This value is used to drop
+ *	tty references for those processes.
+ */
+static int tty_signal_session_leader(struct tty_struct *tty, int exit_session)
+{
+	struct task_struct *p;
+	int refs = 0;
+	struct pid *tty_pgrp = NULL;
+
+	read_lock(&tasklist_lock);
+	if (tty->session) {
+		do_each_pid_task(tty->session, PIDTYPE_SID, p) {
+			spin_lock_irq(&p->sighand->siglock);
+			if (p->signal->tty == tty) {
+				p->signal->tty = NULL;
+				/* We defer the dereferences outside fo
+				   the tasklist lock */
+				refs++;
+			}
+			if (!p->signal->leader) {
+				spin_unlock_irq(&p->sighand->siglock);
+				continue;
+			}
+			__group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p);
+			__group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p);
+			put_pid(p->signal->tty_old_pgrp);  /* A noop */
+			spin_lock(&tty->ctrl_lock);
+			tty_pgrp = get_pid(tty->pgrp);
+			if (tty->pgrp)
+				p->signal->tty_old_pgrp = get_pid(tty->pgrp);
+			spin_unlock(&tty->ctrl_lock);
+			spin_unlock_irq(&p->sighand->siglock);
+		} while_each_pid_task(tty->session, PIDTYPE_SID, p);
+	}
+	read_unlock(&tasklist_lock);
+
+	if (tty_pgrp) {
+		if (exit_session)
+			kill_pgrp(tty_pgrp, SIGHUP, exit_session);
+		put_pid(tty_pgrp);
+	}
+
+	return refs;
+}
+
+/**
  *	__tty_hangup		-	actual handler for hangup events
  *	@work: tty device
  *
···
  *		  tasklist_lock to walk task list for hangup event
  *		    ->siglock to protect ->signal/->sighand
  */
-static void __tty_hangup(struct tty_struct *tty)
+static void __tty_hangup(struct tty_struct *tty, int exit_session)
 {
 	struct file *cons_filp = NULL;
 	struct file *filp, *f = NULL;
-	struct task_struct *p;
 	struct tty_file_private *priv;
 	int    closecount = 0, n;
-	unsigned long flags;
-	int refs = 0;
+	int refs;
 
 	if (!tty)
 		return;
···
 	}
 	spin_unlock(&tty_files_lock);
 
+	refs = tty_signal_session_leader(tty, exit_session);
+	/* Account for the p->signal references we killed */
+	while (refs--)
+		tty_kref_put(tty);
+
 	/*
 	 * it drops BTM and thus races with reopen
 	 * we protect the race by TTY_HUPPING
 	 */
 	tty_ldisc_hangup(tty);
 
-	read_lock(&tasklist_lock);
-	if (tty->session) {
-		do_each_pid_task(tty->session, PIDTYPE_SID, p) {
-			spin_lock_irq(&p->sighand->siglock);
-			if (p->signal->tty == tty) {
-				p->signal->tty = NULL;
-				/* We defer the dereferences outside fo
-				   the tasklist lock */
-				refs++;
-			}
-			if (!p->signal->leader) {
-				spin_unlock_irq(&p->sighand->siglock);
-				continue;
-			}
-			__group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p);
-			__group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p);
-			put_pid(p->signal->tty_old_pgrp);  /* A noop */
-			spin_lock_irqsave(&tty->ctrl_lock, flags);
-			if (tty->pgrp)
-				p->signal->tty_old_pgrp = get_pid(tty->pgrp);
-			spin_unlock_irqrestore(&tty->ctrl_lock, flags);
-			spin_unlock_irq(&p->sighand->siglock);
-		} while_each_pid_task(tty->session, PIDTYPE_SID, p);
-	}
-	read_unlock(&tasklist_lock);
-
-	spin_lock_irqsave(&tty->ctrl_lock, flags);
+	spin_lock_irq(&tty->ctrl_lock);
 	clear_bit(TTY_THROTTLED, &tty->flags);
 	clear_bit(TTY_PUSH, &tty->flags);
 	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
···
 	tty->session = NULL;
 	tty->pgrp = NULL;
 	tty->ctrl_status = 0;
-	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
-
-	/* Account for the p->signal references we killed */
-	while (refs--)
-		tty_kref_put(tty);
+	spin_unlock_irq(&tty->ctrl_lock);
 
 	/*
 	 * If one of the devices matches a console pointer, we
···
 	 */
 	set_bit(TTY_HUPPED, &tty->flags);
 	clear_bit(TTY_HUPPING, &tty->flags);
-	tty_ldisc_enable(tty);
 
 	tty_unlock(tty);
 
···
 	struct tty_struct *tty =
 		container_of(work, struct tty_struct, hangup_work);
 
-	__tty_hangup(tty);
+	__tty_hangup(tty, 0);
 }
 
 /**
···
 
 	printk(KERN_DEBUG "%s vhangup...\n", tty_name(tty, buf));
 #endif
-	__tty_hangup(tty);
+	__tty_hangup(tty, 0);
 }
 
 EXPORT_SYMBOL(tty_vhangup);
···
 		tty_vhangup(tty);
 		tty_kref_put(tty);
 	}
+}
+
+/**
+ *	tty_vhangup_session		-	hangup session leader exit
+ *	@tty: tty to hangup
+ *
+ *	The session leader is exiting and hanging up its controlling terminal.
+ *	Every process in the foreground process group is signalled SIGHUP.
+ *
+ *	We do this synchronously so that when the syscall returns the process
+ *	is complete. That guarantee is necessary for security reasons.
+ */
+
+static void tty_vhangup_session(struct tty_struct *tty)
+{
+#ifdef TTY_DEBUG_HANGUP
+	char	buf[64];
+
+	printk(KERN_DEBUG "%s vhangup session...\n", tty_name(tty, buf));
+#endif
+	__tty_hangup(tty, 1);
 }
 
 /**
···
 
 	tty = get_current_tty();
 	if (tty) {
-		struct pid *tty_pgrp = get_pid(tty->pgrp);
-		if (on_exit) {
-			if (tty->driver->type != TTY_DRIVER_TYPE_PTY)
-				tty_vhangup(tty);
+		if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY) {
+			tty_vhangup_session(tty);
+		} else {
+			struct pid *tty_pgrp = tty_get_pgrp(tty);
+			if (tty_pgrp) {
+				kill_pgrp(tty_pgrp, SIGHUP, on_exit);
+				kill_pgrp(tty_pgrp, SIGCONT, on_exit);
+				put_pid(tty_pgrp);
+			}
 		}
 		tty_kref_put(tty);
-		if (tty_pgrp) {
-			kill_pgrp(tty_pgrp, SIGHUP, on_exit);
-			if (!on_exit)
-				kill_pgrp(tty_pgrp, SIGCONT, on_exit);
-			put_pid(tty_pgrp);
-		}
+
 	} else if (on_exit) {
 		struct pid *old_pgrp;
 		spin_lock_irq(&current->sighand->siglock);
···
 	}
 	tty->count++;
 
-	mutex_lock(&tty->ldisc_mutex);
 	WARN_ON(!test_bit(TTY_LDISC, &tty->flags));
-	mutex_unlock(&tty->ldisc_mutex);
 
 	return 0;
 }
···
 }
 EXPORT_SYMBOL(tty_free_termios);
 
+/**
+ *	tty_flush_works		-	flush all works of a tty
+ *	@tty: tty device to flush works for
+ *
+ *	Sync flush all works belonging to @tty.
+ */
+static void tty_flush_works(struct tty_struct *tty)
+{
+	flush_work(&tty->SAK_work);
+	flush_work(&tty->hangup_work);
+}
 
 /**
  *	release_one_tty		-	release tty structure memory
···
 	tty_free_termios(tty);
 	tty_driver_remove_tty(tty->driver, tty);
 	tty->port->itty = NULL;
+	cancel_work_sync(&tty->port->buf.work);
 
 	if (tty->link)
 		tty_kref_put(tty->link);
···
 		return 0;
 
 #ifdef TTY_DEBUG_HANGUP
-	printk(KERN_DEBUG "%s: freeing tty structure...\n", __func__);
+	printk(KERN_DEBUG "%s: %s: final close\n", __func__, tty_name(tty, buf));
 #endif
 	/*
 	 * Ask the line discipline code to release its structures
 	 */
 	tty_ldisc_release(tty, o_tty);
+
+	/* Wait for pending work before tty destruction commmences */
+	tty_flush_works(tty);
+	if (o_tty)
+		tty_flush_works(o_tty);
+
+#ifdef TTY_DEBUG_HANGUP
+	printk(KERN_DEBUG "%s: %s: freeing structure...\n", __func__, tty_name(tty, buf));
+#endif
 	/*
 	 * The release_tty function takes care of the details of clearing
 	 * the slots and preserving the termios structure. The tty_unlock_pair

drivers/tty/tty_ioctl.c

···
 	if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) &&
 	    tty->ops->throttle)
 		tty->ops->throttle(tty);
+	tty->flow_change = 0;
 	mutex_unlock(&tty->termios_mutex);
 }
 EXPORT_SYMBOL(tty_throttle);
···
 	if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) &&
 	    tty->ops->unthrottle)
 		tty->ops->unthrottle(tty);
+	tty->flow_change = 0;
 	mutex_unlock(&tty->termios_mutex);
 }
 EXPORT_SYMBOL(tty_unthrottle);
+
+/**
+ *	tty_throttle_safe	-	flow control
+ *	@tty: terminal
+ *
+ *	Similar to tty_throttle() but will only attempt throttle
+ *	if tty->flow_change is TTY_THROTTLE_SAFE. Prevents an accidental
+ *	throttle due to race conditions when throttling is conditional
+ *	on factors evaluated prior to throttling.
+ *
+ *	Returns 0 if tty is throttled (or was already throttled)
+ */
+
+int tty_throttle_safe(struct tty_struct *tty)
+{
+	int ret = 0;
+
+	mutex_lock(&tty->termios_mutex);
+	if (!test_bit(TTY_THROTTLED, &tty->flags)) {
+		if (tty->flow_change != TTY_THROTTLE_SAFE)
+			ret = 1;
+		else {
+			set_bit(TTY_THROTTLED, &tty->flags);
+			if (tty->ops->throttle)
+				tty->ops->throttle(tty);
+		}
+	}
+	mutex_unlock(&tty->termios_mutex);
+
+	return ret;
+}
+
+/**
+ *	tty_unthrottle_safe	-	flow control
+ *	@tty: terminal
+ *
+ *	Similar to tty_unthrottle() but will only attempt unthrottle
+ *	if tty->flow_change is TTY_UNTHROTTLE_SAFE. Prevents an accidental
+ *	unthrottle due to race conditions when unthrottling is conditional
+ *	on factors evaluated prior to unthrottling.
+ *
+ *	Returns 0 if tty is unthrottled (or was already unthrottled)
+ */
+
+int tty_unthrottle_safe(struct tty_struct *tty)
+{
+	int ret = 0;
+
+	mutex_lock(&tty->termios_mutex);
+	if (test_bit(TTY_THROTTLED, &tty->flags)) {
+		if (tty->flow_change != TTY_UNTHROTTLE_SAFE)
+			ret = 1;
+		else {
+			clear_bit(TTY_THROTTLED, &tty->flags);
+			if (tty->ops->unthrottle)
+				tty->ops->unthrottle(tty);
+		}
+	}
+	mutex_unlock(&tty->termios_mutex);
+
+	return ret;
+}
 
 /**
  *	tty_wait_until_sent	-	wait for I/O to finish
···
 	tty_termios_encode_baud_rate(&tty->termios, ibaud, obaud);
 }
 EXPORT_SYMBOL_GPL(tty_encode_baud_rate);
-
-/**
- *	tty_get_baud_rate	-	get tty bit rates
- *	@tty: tty to query
- *
- *	Returns the baud rate as an integer for this terminal. The
- *	termios lock must be held by the caller and the terminal bit
- *	flags may be updated.
- *
- *	Locking: none
- */
-
-speed_t tty_get_baud_rate(struct tty_struct *tty)
-{
-	speed_t baud = tty_termios_baud_rate(&tty->termios);
-
-	if (baud == 38400 && tty->alt_speed) {
-		if (!tty->warned) {
-			printk(KERN_WARNING "Use of setserial/setrocket to "
-					    "set SPD_* flags is deprecated\n");
-			tty->warned = 1;
-		}
-		baud = tty->alt_speed;
-	}
-
-	return baud;
-}
-EXPORT_SYMBOL(tty_get_baud_rate);
 
 /**
  *	tty_termios_copy_hw	-	copy hardware settings
···
 }
 EXPORT_SYMBOL_GPL(tty_mode_ioctl);
 
-int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
-{
-	struct tty_ldisc *ld;
-	int retval = tty_check_change(tty);
-	if (retval)
-		return retval;
 
-	ld = tty_ldisc_ref_wait(tty);
+/* Caller guarantees ldisc reference is held */
+static int __tty_perform_flush(struct tty_struct *tty, unsigned long arg)
+{
+	struct tty_ldisc *ld = tty->ldisc;
+
 	switch (arg) {
 	case TCIFLUSH:
 		if (ld && ld->ops->flush_buffer) {
···
 		tty_driver_flush_buffer(tty);
 		break;
 	default:
-		tty_ldisc_deref(ld);
 		return -EINVAL;
 	}
-	tty_ldisc_deref(ld);
 	return 0;
+}
+
+int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
+{
+	struct tty_ldisc *ld;
+	int retval = tty_check_change(tty);
+	if (retval)
+		return retval;
+
+	ld = tty_ldisc_ref_wait(tty);
+	retval = __tty_perform_flush(tty, arg);
+	if (ld)
+		tty_ldisc_deref(ld);
+	return retval;
 }
 EXPORT_SYMBOL_GPL(tty_perform_flush);
 
···
 		}
 		return 0;
 	case TCFLSH:
-		return tty_perform_flush(tty, arg);
+		return __tty_perform_flush(tty, arg);
 	default:
 		/* Try the mode commands */
 		return tty_mode_ioctl(tty, file, cmd, arg);

drivers/tty/tty_ldisc.c

···
 #include <linux/uaccess.h>
 #include <linux/ratelimit.h>
 
+#undef LDISC_DEBUG_HANGUP
+
+#ifdef LDISC_DEBUG_HANGUP
+#define tty_ldisc_debug(tty, f, args...) ({				       \
+	char __b[64];							       \
+	printk(KERN_DEBUG "%s: %s: " f, __func__, tty_name(tty, __b), ##args); \
+})
+#else
+#define tty_ldisc_debug(tty, f, args...)
+#endif
+
 /*
  *	This guards the refcounted line discipline lists. The lock
  *	must be taken with irqs off because there are hangup path
···
 static DECLARE_WAIT_QUEUE_HEAD(tty_ldisc_wait);
 /* Line disc dispatch table */
 static struct tty_ldisc_ops *tty_ldiscs[NR_LDISCS];
-
-static inline struct tty_ldisc *get_ldisc(struct tty_ldisc *ld)
-{
-	if (ld)
-		atomic_inc(&ld->users);
-	return ld;
-}
-
-static void put_ldisc(struct tty_ldisc *ld)
-{
-	unsigned long flags;
-
-	if (WARN_ON_ONCE(!ld))
-		return;
-
-	/*
-	 * If this is the last user, free the ldisc, and
-	 * release the ldisc ops.
-	 *
-	 * We really want an "atomic_dec_and_raw_lock_irqsave()",
-	 * but we don't have it, so this does it by hand.
-	 */
-	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
-	if (atomic_dec_and_test(&ld->users)) {
-		struct tty_ldisc_ops *ldo = ld->ops;
-
-		ldo->refcount--;
-		module_put(ldo->owner);
-		raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
-
-		kfree(ld);
-		return;
-	}
-	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
-
-	if (waitqueue_active(&ld->wq_idle))
-		wake_up(&ld->wq_idle);
-}
 
 /**
  *	tty_register_ldisc	-	install a line discipline
···
 	return ld;
 }
 
+/**
+ *	tty_ldisc_put		-	release the ldisc
+ *
+ *	Complement of tty_ldisc_get().
+ */
+static inline void tty_ldisc_put(struct tty_ldisc *ld)
+{
+	unsigned long flags;
+
+	if (WARN_ON_ONCE(!ld))
+		return;
+
+	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
+
+	/* unreleased reader reference(s) will cause this WARN */
+	WARN_ON(!atomic_dec_and_test(&ld->users));
+
+	ld->ops->refcount--;
+	module_put(ld->ops->owner);
+	kfree(ld);
+	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+}
+
 static void *tty_ldiscs_seq_start(struct seq_file *m, loff_t *pos)
 {
 	return (*pos < NR_LDISCS) ? pos : NULL;
···
 };
 
 /**
- *	tty_ldisc_assign	-	set ldisc on a tty
- *	@tty: tty to assign
- *	@ld: line discipline
- *
- *	Install an instance of a line discipline into a tty structure. The
- *	ldisc must have a reference count above zero to ensure it remains.
- *	The tty instance refcount starts at zero.
- *
- *	Locking:
- *		Caller must hold references
- */
-
-static void tty_ldisc_assign(struct tty_struct *tty, struct tty_ldisc *ld)
-{
-	tty->ldisc = ld;
-}
-
-/**
  *	tty_ldisc_try		-	internal helper
  *	@tty: the tty
  *
···
 	unsigned long flags;
 	struct tty_ldisc *ld;
 
+	/* FIXME: this allows reference acquire after TTY_LDISC is cleared */
 	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
 	ld = NULL;
-	if (test_bit(TTY_LDISC, &tty->flags))
-		ld = get_ldisc(tty->ldisc);
+	if (test_bit(TTY_LDISC, &tty->flags) && tty->ldisc) {
+		ld = tty->ldisc;
+		atomic_inc(&ld->users);
+	}
 	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
 	return ld;
 }
···
 
 void tty_ldisc_deref(struct tty_ldisc *ld)
 {
-	put_ldisc(ld);
+	unsigned long flags;
+
+	if (WARN_ON_ONCE(!ld))
+		return;
+
+	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
+	/*
+	 * WARNs if one-too-many reader references were released
+	 * - the last reference must be released with tty_ldisc_put
+	 */
+	WARN_ON(atomic_dec_and_test(&ld->users));
+	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+
+	if (waitqueue_active(&ld->wq_idle))
+		wake_up(&ld->wq_idle);
 }
 EXPORT_SYMBOL_GPL(tty_ldisc_deref);
-
-static inline void tty_ldisc_put(struct tty_ldisc *ld)
-{
-	put_ldisc(ld);
-}
 
 /**
  *	tty_ldisc_enable	-	allow ldisc use
···
  *	Clearing directly is allowed.
  */
 
-void tty_ldisc_enable(struct tty_struct *tty)
+static void tty_ldisc_enable(struct tty_struct *tty)
 {
+	clear_bit(TTY_LDISC_HALTED, &tty->flags);
 	set_bit(TTY_LDISC, &tty->flags);
 	clear_bit(TTY_LDISC_CHANGING, &tty->flags);
 	wake_up(&tty_ldisc_wait);
···
 	/* There is an outstanding reference here so this is safe */
 	old = tty_ldisc_get(old->ops->num);
 	WARN_ON(IS_ERR(old));
-	tty_ldisc_assign(tty, old);
+	tty->ldisc = old;
 	tty_set_termios_ldisc(tty, old->ops->num);
 	if (tty_ldisc_open(tty, old) < 0) {
 		tty_ldisc_put(old);
···
 		new_ldisc = tty_ldisc_get(N_TTY);
 		if (IS_ERR(new_ldisc))
 			panic("n_tty: get");
-		tty_ldisc_assign(tty, new_ldisc);
+		tty->ldisc = new_ldisc;
 		tty_set_termios_ldisc(tty, N_TTY);
 		r = tty_ldisc_open(tty, new_ldisc);
 		if (r < 0)
···
 			      "%s --- error %d.",
 			      tty_name(tty, buf), r);
 	}
-}
-
-/**
- *	tty_ldisc_halt		-	shut down the line discipline
- *	@tty: tty device
- *
- *	Shut down the line discipline and work queue for this tty device.
- *	The TTY_LDISC flag being cleared ensures no further references can
- *	be obtained while the delayed work queue halt ensures that no more
- *	data is fed to the ldisc.
- *
- *	You need to do a 'flush_scheduled_work()' (outside the ldisc_mutex)
- *	in order to make sure any currently executing ldisc work is also
- *	flushed.
- */
-
-static int tty_ldisc_halt(struct tty_struct *tty)
-{
-	clear_bit(TTY_LDISC, &tty->flags);
-	return cancel_work_sync(&tty->port->buf.work);
-}
-
-/**
- *	tty_ldisc_flush_works	-	flush all works of a tty
- *	@tty: tty device to flush works for
- *
- *	Sync flush all works belonging to @tty.
- */
-static void tty_ldisc_flush_works(struct tty_struct *tty)
-{
-	flush_work(&tty->hangup_work);
-	flush_work(&tty->SAK_work);
-	flush_work(&tty->port->buf.work);
 }
 
 /**
···
 }
 
 /**
+ *	tty_ldisc_halt		-	shut down the line discipline
+ *	@tty: tty device
+ *	@o_tty: paired pty device (can be NULL)
+ *	@timeout: # of jiffies to wait for ldisc refs to be released
+ *
+ *	Shut down the line discipline and work queue for this tty device and
+ *	its paired pty (if exists). Clearing the TTY_LDISC flag ensures
+ *	no further references can be obtained, while waiting for existing
+ *	references to be released ensures no more data is fed to the ldisc.
+ *
+ *	You need to do a 'flush_scheduled_work()' (outside the ldisc_mutex)
+ *	in order to make sure any currently executing ldisc work is also
+ *	flushed.
+ */
+
+static int tty_ldisc_halt(struct tty_struct *tty, struct tty_struct *o_tty,
+			  long timeout)
+{
+	int retval;
+
+	clear_bit(TTY_LDISC, &tty->flags);
+	if (o_tty)
+		clear_bit(TTY_LDISC, &o_tty->flags);
+
+	retval = tty_ldisc_wait_idle(tty, timeout);
+	if (!retval && o_tty)
+		retval = tty_ldisc_wait_idle(o_tty, timeout);
+	if (retval)
+		return retval;
+
+	set_bit(TTY_LDISC_HALTED, &tty->flags);
+	if (o_tty)
+		set_bit(TTY_LDISC_HALTED, &o_tty->flags);
+
+	return 0;
+}
+
+/**
+ *	tty_ldisc_hangup_halt - halt the line discipline for hangup
+ *	@tty: tty being hung up
+ *
+ *	Shut down the line discipline and work queue for the tty device
+ *	being hungup. Clear the TTY_LDISC flag to ensure no further
+ *	references can be obtained and wait for remaining references to be
+ *	released to ensure no more data is fed to this ldisc.
+ *	Caller must hold legacy and ->ldisc_mutex.
+ *
+ *	NB: tty_set_ldisc() is prevented from changing the ldisc concurrently
+ *	with this function by checking the TTY_HUPPING flag.
+ */
+static bool tty_ldisc_hangup_halt(struct tty_struct *tty)
+{
+	char cur_n[TASK_COMM_LEN], tty_n[64];
+	long timeout = 3 * HZ;
+
+	clear_bit(TTY_LDISC, &tty->flags);
+
+	if (tty->ldisc) {	/* Not yet closed */
+		tty_unlock(tty);
+
+		while (tty_ldisc_wait_idle(tty, timeout) == -EBUSY) {
+			timeout = MAX_SCHEDULE_TIMEOUT;
+			printk_ratelimited(KERN_WARNING
+				"%s: waiting (%s) for %s took too long, but we keep waiting...\n",
+				__func__, get_task_comm(cur_n, current),
+				tty_name(tty, tty_n));
+		}
+
+		set_bit(TTY_LDISC_HALTED, &tty->flags);
+
+		/* must reacquire both locks and preserve lock order */
+		mutex_unlock(&tty->ldisc_mutex);
+		tty_lock(tty);
+		mutex_lock(&tty->ldisc_mutex);
+	}
+	return !!tty->ldisc;
+}
+
+/**
  *	tty_set_ldisc		-	set line discipline
  *	@tty: the terminal to set
  *	@ldisc: the line discipline
···
 {
 	int retval;
 	struct tty_ldisc *o_ldisc, *new_ldisc;
-	int work, o_work = 0;
 	struct tty_struct *o_tty;
 
 	new_ldisc = tty_ldisc_get(ldisc);
···
 		return 0;
 	}
 
-	tty_unlock(tty);
-	/*
-	 *	Problem: What do we do if this blocks ?
-	 *	We could deadlock here
-	 */
-
-	tty_wait_until_sent(tty, 0);
-
-	tty_lock(tty);
 	mutex_lock(&tty->ldisc_mutex);
 
 	/*
···
 	 *	parallel to the change and re-referencing the tty.
 	 */
 
-	work = tty_ldisc_halt(tty);
-	if (o_tty)
-		o_work = tty_ldisc_halt(o_tty);
+	retval = tty_ldisc_halt(tty, o_tty, 5 * HZ);
 
 	/*
-	 * Wait for ->hangup_work and ->buf.work handlers to terminate.
+	 * Wait for hangup to complete, if pending.
 	 * We must drop the mutex here in case a hangup is also in process.
 	 */
 
 	mutex_unlock(&tty->ldisc_mutex);
 
-	tty_ldisc_flush_works(tty);
-
-	retval = tty_ldisc_wait_idle(tty, 5 * HZ);
+	flush_work(&tty->hangup_work);
 
 	tty_lock(tty);
 	mutex_lock(&tty->ldisc_mutex);
···
 	tty_ldisc_close(tty, o_ldisc);
 
 	/* Now set up the new line discipline. */
-	tty_ldisc_assign(tty, new_ldisc);
+	tty->ldisc = new_ldisc;
 	tty_set_termios_ldisc(tty, ldisc);
 
 	retval = tty_ldisc_open(tty, new_ldisc);
···
 
 	/* Restart the work queue in case no characters kick it off. Safe if
 	   already running */
-	if (work)
-		schedule_work(&tty->port->buf.work);
-	if (o_work)
+	schedule_work(&tty->port->buf.work);
+	if (o_tty)
 		schedule_work(&o_tty->port->buf.work);
+
 	mutex_unlock(&tty->ldisc_mutex);
 	tty_unlock(tty);
 	return retval;
···
 
 	tty_ldisc_close(tty, tty->ldisc);
 	tty_ldisc_put(tty->ldisc);
-	tty->ldisc = NULL;
 	/*
 	 *	Switch the line discipline back
 	 */
-	tty_ldisc_assign(tty, ld);
+	tty->ldisc = ld;
 	tty_set_termios_ldisc(tty, ldisc);
 
 	return 0;
···
 	struct tty_ldisc *ld;
 	int reset = tty->driver->flags & TTY_DRIVER_RESET_TERMIOS;
 	int err = 0;
+
+	tty_ldisc_debug(tty, "closing ldisc: %p\n", tty->ldisc);
 
 	/*
 	 * FIXME! What are the locking issues here? This may me overdoing
···
 	 */
 	mutex_lock(&tty->ldisc_mutex);
 
-	/*
-	 * this is like tty_ldisc_halt, but we need to give up
-	 * the BTM before calling cancel_work_sync, which may
-	 * need to wait for another function taking the BTM
-	 */
-	clear_bit(TTY_LDISC, &tty->flags);
-	tty_unlock(tty);
-	cancel_work_sync(&tty->port->buf.work);
-	mutex_unlock(&tty->ldisc_mutex);
-retry:
-	tty_lock(tty);
-	mutex_lock(&tty->ldisc_mutex);
+	if (tty_ldisc_hangup_halt(tty)) {
 
-	/* At this point we have a closed ldisc and we want to
-	   reopen it. We could defer this to the next open but
-	   it means auditing a lot of other paths so this is
-	   a FIXME */
-	if (tty->ldisc) {	/* Not yet closed */
-		if (atomic_read(&tty->ldisc->users) != 1) {
-			char cur_n[TASK_COMM_LEN], tty_n[64];
-			long timeout = 3 * HZ;
-			tty_unlock(tty);
-
-			while (tty_ldisc_wait_idle(tty, timeout) == -EBUSY) {
-				timeout = MAX_SCHEDULE_TIMEOUT;
-				printk_ratelimited(KERN_WARNING
-					"%s: waiting (%s) for %s took too long, but we keep waiting...\n",
-					__func__, get_task_comm(cur_n, current),
-					tty_name(tty, tty_n));
-			}
-			mutex_unlock(&tty->ldisc_mutex);
-			goto retry;
-		}
-
+		/* At this point we have a halted ldisc; we want to close it and
+		   reopen a new ldisc. We could defer the reopen to the next
+		   open but it means auditing a lot of other paths so this is
+		   a FIXME */
 		if (reset == 0) {
 
 			if (!tty_ldisc_reinit(tty, tty->termios.c_line))
···
 	mutex_unlock(&tty->ldisc_mutex);
 	if (reset)
 		tty_reset_termios(tty);
+
+	tty_ldisc_debug(tty, "re-opened ldisc: %p\n", tty->ldisc);
 }
 
 /**
···
 
 static void tty_ldisc_kill(struct tty_struct *tty)
 {
-	/* There cannot be users from userspace now. But there still might be
-	 * drivers holding a reference via tty_ldisc_ref. Do not steal them the
-	 * ldisc until they are done. */
-	tty_ldisc_wait_idle(tty, MAX_SCHEDULE_TIMEOUT);
-
 	mutex_lock(&tty->ldisc_mutex);
 	/*
 	 * Now kill off the ldisc
···
 void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty)
 {
 	/*
-	 * Prevent flush_to_ldisc() from rescheduling the work for later.  Then
-	 * kill any delayed work. As this is the final close it does not
-	 * race with the set_ldisc code path.
+	 * Shutdown this line discipline. As this is the final close,
+	 * it does not race with the set_ldisc code path.
 	 */
 
-	tty_ldisc_halt(tty);
-	if (o_tty)
-		tty_ldisc_halt(o_tty);
+	tty_ldisc_debug(tty, "closing ldisc: %p\n", tty->ldisc);
 
-	tty_ldisc_flush_works(tty);
-	if (o_tty)
-		tty_ldisc_flush_works(o_tty);
+	tty_ldisc_halt(tty, o_tty, MAX_SCHEDULE_TIMEOUT);
 
 	tty_lock_pair(tty, o_tty);
 	/* This will need doing differently if we need to lock */
···
 	tty_unlock_pair(tty, o_tty);
 	/* And the memory resources remaining (buffers, termios) will be
 	   disposed of when the kref hits zero */
+
+	tty_ldisc_debug(tty, "ldisc closed\n");
 }
 
 /**
···
 	struct tty_ldisc *ld = tty_ldisc_get(N_TTY);
 	if (IS_ERR(ld))
 		panic("n_tty: init_tty");
-	tty_ldisc_assign(tty, ld);
+	tty->ldisc = ld;
 }
 
 /**
···
  */
 void tty_ldisc_deinit(struct tty_struct *tty)
 {
-	put_ldisc(tty->ldisc);
-	tty_ldisc_assign(tty, NULL);
+	tty_ldisc_put(tty->ldisc);
+	tty->ldisc = NULL;
 }
 
 void tty_ldisc_begin(void)

drivers/tty/tty_port.c

···
  */
 void tty_port_destroy(struct tty_port *port)
 {
+	cancel_work_sync(&port->buf.work);
 	tty_buffer_free_all(port);
 }
 EXPORT_SYMBOL(tty_port_destroy);
···
 }
 EXPORT_SYMBOL(tty_port_tty_set);
 
-static void tty_port_shutdown(struct tty_port *port)
+static void tty_port_shutdown(struct tty_port *port, struct tty_struct *tty)
 {
 	mutex_lock(&port->mutex);
-	if (port->ops->shutdown && !port->console &&
-		test_and_clear_bit(ASYNCB_INITIALIZED, &port->flags))
+	if (port->console)
+		goto out;
+
+	if (test_and_clear_bit(ASYNCB_INITIALIZED, &port->flags)) {
+		/*
+		 * Drop DTR/RTS if HUPCL is set. This causes any attached
+		 * modem to hang up the line.
+		 */
+		if (tty && C_HUPCL(tty))
+			tty_port_lower_dtr_rts(port);
+
+		if (port->ops->shutdown)
 			port->ops->shutdown(port);
+	}
+out:
 	mutex_unlock(&port->mutex);
 }
 
···
 
 void tty_port_hangup(struct tty_port *port)
 {
+	struct tty_struct *tty;
 	unsigned long flags;
 
 	spin_lock_irqsave(&port->lock, flags);
 	port->count = 0;
 	port->flags &= ~ASYNC_NORMAL_ACTIVE;
-	if (port->tty) {
-		set_bit(TTY_IO_ERROR, &port->tty->flags);
-		tty_kref_put(port->tty);
-	}
+	tty = port->tty;
+	if (tty)
+		set_bit(TTY_IO_ERROR, &tty->flags);
 	port->tty = NULL;
 	spin_unlock_irqrestore(&port->lock, flags);
+	tty_port_shutdown(port, tty);
+	tty_kref_put(tty);
 	wake_up_interruptible(&port->open_wait);
 	wake_up_interruptible(&port->delta_msr_wait);
-	tty_port_shutdown(port);
 }
 EXPORT_SYMBOL(tty_port_hangup);
+
+/**
+ * tty_port_tty_hangup - helper to hang up a tty
+ *
+ * @port: tty port
+ * @check_clocal: hang only ttys with CLOCAL unset?
+ */
+void tty_port_tty_hangup(struct tty_port *port, bool check_clocal)
+{
+	struct tty_struct *tty = tty_port_tty_get(port);
+
+	if (tty && (!check_clocal || !C_CLOCAL(tty))) {
+		tty_hangup(tty);
+		tty_kref_put(tty);
+	}
+}
+EXPORT_SYMBOL_GPL(tty_port_tty_hangup);
+
+/**
+ * tty_port_tty_wakeup - helper to wake up a tty
+ *
+ * @port: tty port
+ */
+void tty_port_tty_wakeup(struct tty_port *port)
+{
+	struct tty_struct *tty = tty_port_tty_get(port);
+
+	if (tty) {
+		tty_wakeup(tty);
+		tty_kref_put(tty);
+	}
+}
+EXPORT_SYMBOL_GPL(tty_port_tty_wakeup);
 
 /**
  *	tty_port_carrier_raised	-	carrier raised check
···
 
 	while (1) {
 		/* Indicate we are open */
-		if (tty->termios.c_cflag & CBAUD)
+		if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
 			tty_port_raise_dtr_rts(port);
 
 		prepare_to_wait(&port->open_wait, &wait, TASK_INTERRUPTIBLE);
···
 }
 EXPORT_SYMBOL(tty_port_block_til_ready);
 
+static void tty_port_drain_delay(struct tty_port *port, struct tty_struct *tty)
+{
+	unsigned int bps = tty_get_baud_rate(tty);
+	long timeout;
+
+	if (bps > 1200) {
+		timeout = (HZ * 10 * port->drain_delay) / bps;
+		timeout = max_t(long, timeout, HZ / 10);
+	} else {
+		timeout = 2 * HZ;
+	}
+	schedule_timeout_interruptible(timeout);
+}
+
 int tty_port_close_start(struct tty_port *port,
 				struct tty_struct *tty, struct file *filp)
 {
···
 	set_bit(ASYNCB_CLOSING, &port->flags);
 	tty->closing = 1;
 	spin_unlock_irqrestore(&port->lock, flags);
-	/* Don't block on a stalled port, just pull the chain */
-	if (tty->flow_stopped)
-		tty_driver_flush_buffer(tty);
-	if (test_bit(ASYNCB_INITIALIZED, &port->flags) &&
-			port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
-		tty_wait_until_sent_from_close(tty, port->closing_wait);
-	if (port->drain_delay) {
-		unsigned int bps = tty_get_baud_rate(tty);
-		long timeout;
 
-		if (bps > 1200)
-			timeout = max_t(long,
-				(HZ * 10 * port->drain_delay) / bps, HZ / 10);
-		else
-			timeout = 2 * HZ;
-		schedule_timeout_interruptible(timeout);
+	if (test_bit(ASYNCB_INITIALIZED, &port->flags)) {
+		/* Don't block on a stalled port, just pull the chain */
+		if (tty->flow_stopped)
+			tty_driver_flush_buffer(tty);
+		if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
+			tty_wait_until_sent_from_close(tty, port->closing_wait);
+		if (port->drain_delay)
+			tty_port_drain_delay(port, tty);
 	}
 	/* Flush the ldisc buffering */
 	tty_ldisc_flush(tty);
-
-	/* Drop DTR/RTS if HUPCL is set. This causes any attached modem to
-	   hang up the line */
-	if (tty->termios.c_cflag & HUPCL)
-		tty_port_lower_dtr_rts(port);
 
 	/* Don't call port->drop for the last reference. Callers will want
 	   to drop the last active reference in ->shutdown() or the tty
···
 {
 	if (tty_port_close_start(port, tty, filp) == 0)
 		return;
-	tty_port_shutdown(port);
+	tty_port_shutdown(port, tty);
 	set_bit(TTY_IO_ERROR, &tty->flags);
 	tty_port_close_end(port, tty);
 	tty_port_tty_set(port, NULL);

drivers/tty/vt/consolemap.c

···
 	q = p->inverse_translations[i];
 
 	if (!q) {
-		q = p->inverse_translations[i] = (unsigned char *) 
-			kmalloc(MAX_GLYPH, GFP_KERNEL);
+		q = p->inverse_translations[i] = kmalloc(MAX_GLYPH, GFP_KERNEL);
 		if (!q) return;
 	}
 	memset(q, 0, MAX_GLYPH);

drivers/usb/class/cdc-acm.c

···
 {
 	struct acm *acm = urb->context;
 	struct usb_cdc_notification *dr = urb->transfer_buffer;
-	struct tty_struct *tty;
 	unsigned char *data;
 	int newctrl;
 	int retval;
···
 		break;
 
 	case USB_CDC_NOTIFY_SERIAL_STATE:
-		tty = tty_port_tty_get(&acm->port);
 		newctrl = get_unaligned_le16(data);
 
-		if (tty) {
-			if (!acm->clocal &&
-				(acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
-				dev_dbg(&acm->control->dev,
-					"%s - calling hangup\n", __func__);
-				tty_hangup(tty);
-			}
-			tty_kref_put(tty);
+		if (!acm->clocal && (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
+			dev_dbg(&acm->control->dev, "%s - calling hangup\n",
+					__func__);
+			tty_port_tty_hangup(&acm->port, false);
 		}
 
 		acm->ctrlin = newctrl;
···
 static void acm_softint(struct work_struct *work)
 {
 	struct acm *acm = container_of(work, struct acm, work);
-	struct tty_struct *tty;
 
 	dev_vdbg(&acm->data->dev, "%s\n", __func__);
 
-	tty = tty_port_tty_get(&acm->port);
-	if (!tty)
-		return;
-	tty_wakeup(tty);
-	tty_kref_put(tty);
+	tty_port_tty_wakeup(&acm->port);
 }
 
 /*
···
 static int acm_reset_resume(struct usb_interface *intf)
 {
 	struct acm *acm = usb_get_intfdata(intf);
-	struct tty_struct *tty;
 
-	if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) {
-		tty = tty_port_tty_get(&acm->port);
-		if (tty) {
-			tty_hangup(tty);
-			tty_kref_put(tty);
-		}
-	}
+	if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags))
+		tty_port_tty_hangup(&acm->port, false);
 
 	return acm_resume(intf);
 }

drivers/usb/serial/digi_acceleport.c

···
 
 /* Local Function Declarations */
 
-static void digi_wakeup_write(struct usb_serial_port *port);
 static void digi_wakeup_write_lock(struct work_struct *work);
 static int digi_write_oob_command(struct usb_serial_port *port,
 	unsigned char *buf, int count, int interruptible);
···
 	unsigned long flags;
 
 	spin_lock_irqsave(&priv->dp_port_lock, flags);
-	digi_wakeup_write(port);
+	tty_port_tty_wakeup(&port->port);
 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
 }
-
-static void digi_wakeup_write(struct usb_serial_port *port)
-{
-	struct tty_struct *tty = tty_port_tty_get(&port->port);
-	if (tty) {
-		tty_wakeup(tty);
-		tty_kref_put(tty);
-	}
-}
-
 
 /*
  *  Digi Write OOB Command
···
 		}
 	}
 	/* wake up processes sleeping on writes immediately */
-	digi_wakeup_write(port);
+	tty_port_tty_wakeup(&port->port);
 	/* also queue up a wakeup at scheduler time, in case we */
 	/* lost the race in write_chan(). */
 	schedule_work(&priv->dp_wakeup_work);
···
 				/* port must be open to use tty struct */
 				if (rts) {
 					tty->hw_stopped = 0;
-					digi_wakeup_write(port);
+					tty_port_tty_wakeup(&port->port);
 				}
 			} else {
 				priv->dp_modem_signals &= ~TIOCM_CTS;

drivers/usb/serial/io_edgeport.c

···
 	struct device *dev;
 	struct edgeport_port *edge_port;
 	struct usb_serial_port *port;
-	struct tty_struct *tty;
 	unsigned char *data = urb->transfer_buffer;
 	int length = urb->actual_length;
 	int bytes_avail;
···
 
 					/* tell the tty driver that something
 					   has changed */
-					tty = tty_port_tty_get(
-						&edge_port->port->port);
-					if (tty) {
-						tty_wakeup(tty);
-						tty_kref_put(tty);
-					}
+					tty_port_tty_wakeup(&edge_port->port->port);
 					/* Since we have more credit, check
 					   if more data can be sent */
 					send_more_port_data(edge_serial,
···
 static void edge_bulk_out_data_callback(struct urb *urb)
 {
 	struct edgeport_port *edge_port = urb->context;
-	struct tty_struct *tty;
 	int status = urb->status;
 
 	if (status) {
···
 			__func__, status);
 	}
 
-	tty = tty_port_tty_get(&edge_port->port->port);
-
-	if (tty && edge_port->open) {
-		/* let the tty driver wakeup if it has a special
-		   write_wakeup function */
-		tty_wakeup(tty);
-	}
-	tty_kref_put(tty);
+	if (edge_port->open)
+		tty_port_tty_wakeup(&edge_port->port->port);
 
 	/* Release the Write URB */
 	edge_port->write_in_progress = false;
···
 static void edge_bulk_out_cmd_callback(struct urb *urb)
 {
 	struct edgeport_port *edge_port = urb->context;
-	struct tty_struct *tty;
 	int status = urb->status;
 
 	atomic_dec(&CmdUrbs);
···
 		return;
 	}
 
-	/* Get pointer to tty */
-	tty = tty_port_tty_get(&edge_port->port->port);
-
 	/* tell the tty driver that something has changed */
-	if (tty && edge_port->open)
-		tty_wakeup(tty);
-	tty_kref_put(tty);
+	if (edge_port->open)
+		tty_port_tty_wakeup(&edge_port->port->port);
 
 	/* we have completed the command */
 	edge_port->commandPending = false;

drivers/usb/serial/keyspan.c

···
 	struct usb_serial			*serial;
 	struct usb_serial_port			*port;
 	struct keyspan_port_private	 	*p_priv;
-	struct tty_struct			*tty;
 	int old_dcd_state, err;
 	int status = urb->status;
 
···
 	p_priv->dcd_state = ((msg->gpia_dcd) ? 1 : 0);
 	p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-	if (old_dcd_state != p_priv->dcd_state) {
-		tty = tty_port_tty_get(&port->port);
-		if (tty && !C_CLOCAL(tty))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	if (old_dcd_state != p_priv->dcd_state)
+		tty_port_tty_hangup(&port->port, true);
 
 	/* Resubmit urb so we continue receiving */
 	err = usb_submit_urb(urb, GFP_ATOMIC);
···
 	struct usb_serial			*serial;
 	struct usb_serial_port			*port;
 	struct keyspan_port_private	 	*p_priv;
-	struct tty_struct			*tty;
 	int old_dcd_state;
 	int status = urb->status;
 
···
 	p_priv->dcd_state = ((msg->dcd) ? 1 : 0);
 	p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-	if (old_dcd_state != p_priv->dcd_state && old_dcd_state) {
-		tty = tty_port_tty_get(&port->port);
-		if (tty && !C_CLOCAL(tty))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	if (old_dcd_state != p_priv->dcd_state && old_dcd_state)
+		tty_port_tty_hangup(&port->port, true);
 
 		/* Resubmit urb so we continue receiving */
 	err = usb_submit_urb(urb, GFP_ATOMIC);
···
 	p_priv->dcd_state = ((msg->dcd) ? 1 : 0);
 	p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-	if (old_dcd_state != p_priv->dcd_state && old_dcd_state) {
-		struct tty_struct *tty = tty_port_tty_get(&port->port);
-		if (tty && !C_CLOCAL(tty))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	if (old_dcd_state != p_priv->dcd_state && old_dcd_state)
+		tty_port_tty_hangup(&port->port, true);
 
 	/* Resubmit urb so we continue receiving */
 	err = usb_submit_urb(urb, GFP_ATOMIC);
···
 	struct usb_serial			*serial;
 	struct usb_serial_port			*port;
 	struct keyspan_port_private	 	*p_priv;
-	struct tty_struct			*tty;
 	int old_dcd_state, err;
 	int status = urb->status;
 
···
 	p_priv->dcd_state = ((msg->dcd) ? 1 : 0);
 	p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-	if (old_dcd_state != p_priv->dcd_state && old_dcd_state) {
-		tty = tty_port_tty_get(&port->port);
-		if (tty && !C_CLOCAL(tty))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	if (old_dcd_state != p_priv->dcd_state && old_dcd_state)
+		tty_port_tty_hangup(&port->port, true);
 
 	/* Resubmit urb so we continue receiving */
 	err = usb_submit_urb(urb, GFP_ATOMIC);
···
 	p_priv->cts_state = ((msg->hskia_cts) ? 1 : 0);
 	p_priv->dcd_state = ((msg->gpia_dcd) ? 1 : 0);
 
-	if (old_dcd_state != p_priv->dcd_state && old_dcd_state) {
-		struct tty_struct *tty = tty_port_tty_get(&port->port);
-		if (tty && !C_CLOCAL(tty))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	if (old_dcd_state != p_priv->dcd_state && old_dcd_state)
+		tty_port_tty_hangup(&port->port, true);
 
 	/* Resubmit urb so we continue receiving */
 	err = usb_submit_urb(urb, GFP_ATOMIC);

drivers/usb/serial/keyspan_pda.c

···
 	struct keyspan_pda_private *priv =
 		container_of(work, struct keyspan_pda_private, wakeup_work);
 	struct usb_serial_port *port = priv->port;
-	struct tty_struct *tty = tty_port_tty_get(&port->port);
-	if (tty)
-		tty_wakeup(tty);
-	tty_kref_put(tty);
+
+	tty_port_tty_wakeup(&port->port);
 }
 
 static void keyspan_pda_request_unthrottle(struct work_struct *work)

drivers/usb/serial/mos7720.c

···
 static void mos7720_bulk_out_data_callback(struct urb *urb)
 {
 	struct moschip_port *mos7720_port;
-	struct tty_struct *tty;
 	int status = urb->status;
 
 	if (status) {
···
 		return ;
 	}
 
-	tty = tty_port_tty_get(&mos7720_port->port->port);
-
-	if (tty && mos7720_port->open)
-		tty_wakeup(tty);
-	tty_kref_put(tty);
+	if (mos7720_port->open)
+		tty_port_tty_wakeup(&mos7720_port->port->port);
 }
 
 /*

drivers/usb/serial/mos7840.c

···
 {
 	struct moschip_port *mos7840_port;
 	struct usb_serial_port *port;
-	struct tty_struct *tty;
 	int status = urb->status;
 	int i;
 
···
 	if (mos7840_port_paranoia_check(port, __func__))
 		return;
 
-	tty = tty_port_tty_get(&port->port);
-	if (tty && mos7840_port->open)
-		tty_wakeup(tty);
-	tty_kref_put(tty);
+	if (mos7840_port->open)
+		tty_port_tty_wakeup(&port->port);
 
 }
 

drivers/usb/serial/option.c

···
 			portdata->dsr_state = ((signals & 0x02) ? 1 : 0);
 			portdata->ri_state = ((signals & 0x08) ? 1 : 0);
 
-			if (old_dcd_state && !portdata->dcd_state) {
-				struct tty_struct *tty =
-						tty_port_tty_get(&port->port);
-				if (tty && !C_CLOCAL(tty))
-					tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			if (old_dcd_state && !portdata->dcd_state)
+				tty_port_tty_hangup(&port->port, true);
 		} else {
 			dev_dbg(dev, "%s: type %x req %x\n", __func__,
 				req_pkt->bRequestType, req_pkt->bRequest);

drivers/usb/serial/quatech2.c

···
 };
 
 struct qt2_port_private {
-	bool is_open;
 	u8   device_port;
 
 	spinlock_t urb_lock;
···
 		return status;
 	}
 
-	port_priv->is_open = true;
 	port_priv->device_port = (u8) device_port;
 
 	if (tty)
···
 
 	serial = port->serial;
 	port_priv = usb_get_serial_port_data(port);
-
-	port_priv->is_open = false;
 
 	spin_lock_irqsave(&port_priv->urb_lock, flags);
 	usb_kill_urb(port_priv->write_urb);
···
 						 __func__);
 					break;
 				}
-
-				if (port_priv->is_open)
-					tty_flip_buffer_push(&port->port);
+				tty_flip_buffer_push(&port->port);
 
 				newport = *(ch + 3);
 
···
 		tty_insert_flip_string(&port->port, ch, 1);
 	}
 
-	if (port_priv->is_open)
-		tty_flip_buffer_push(&port->port);
+	tty_flip_buffer_push(&port->port);
 }
 
 static void qt2_write_bulk_callback(struct urb *urb)
···
 	u16 val;
 
 	port_priv = usb_get_serial_port_data(port);
-
-	if (!port_priv->is_open) {
-		dev_err(&port->dev,
-			"%s - port is not open\n", __func__);
-		return;
-	}
 
 	val = (break_state == -1) ? 1 : 0;
 

drivers/usb/serial/sierra.c

···
 			unsigned char signals = *((unsigned char *)
 					urb->transfer_buffer +
 					sizeof(struct usb_ctrlrequest));
-			struct tty_struct *tty;
 
 			dev_dbg(&port->dev, "%s: signal x%x\n", __func__,
 				signals);
···
 			portdata->dsr_state = ((signals & 0x02) ? 1 : 0);
 			portdata->ri_state = ((signals & 0x08) ? 1 : 0);
 
-			tty = tty_port_tty_get(&port->port);
-			if (tty && !C_CLOCAL(tty) &&
-					old_dcd_state && !portdata->dcd_state)
-				tty_hangup(tty);
-			tty_kref_put(tty);
+			if (old_dcd_state && !portdata->dcd_state)
+				tty_port_tty_hangup(&port->port, true);
 		} else {
 			dev_dbg(&port->dev, "%s: type %x req %x\n",
 				__func__, req_pkt->bRequestType,

drivers/usb/serial/ti_usb_3410_5052.c

···
 {
 	int count, result;
 	struct usb_serial_port *port = tport->tp_port;
-	struct tty_struct *tty = tty_port_tty_get(&port->port);	/* FIXME */
 	unsigned long flags;
 
 	spin_lock_irqsave(&tport->tp_lock, flags);
···
 	}
 
 	/* more room in the buffer for new writes, wakeup */
-	if (tty)
-		tty_wakeup(tty);
-	tty_kref_put(tty);
+	tty_port_tty_wakeup(&port->port);
+
 	wake_up_interruptible(&tport->tp_write_wait);
 	return;
 unlock:
 	spin_unlock_irqrestore(&tport->tp_lock, flags);
-	tty_kref_put(tty);
 	return;
 }
 

drivers/usb/serial/usb-serial.c

···
 {
 	struct usb_serial_port *port =
 		container_of(work, struct usb_serial_port, work);
-	struct tty_struct *tty;
 
-	tty = tty_port_tty_get(&port->port);
-	if (!tty)
-		return;
-
-	dev_dbg(tty->dev, "%s - port %d\n", __func__, port->number);
-
-	tty_wakeup(tty);
-	tty_kref_put(tty);
+	tty_port_tty_wakeup(&port->port);
 }
 
 static void kill_traffic(struct usb_serial_port *port)

include/linux/amba/serial.h

···
 	bool (*dma_filter)(struct dma_chan *chan, void *filter_param);
 	void *dma_rx_param;
 	void *dma_tx_param;
+	bool dma_rx_poll_enable;
+	unsigned int dma_rx_poll_rate;
+	unsigned int dma_rx_poll_timeout;
         void (*init) (void);
 	void (*exit) (void);
 };

include/linux/platform_data/serial-sccnxp.h

···
 	const u32		mctrl_cfg[SCCNXP_MAX_UARTS];
 	/* Timer value for polling mode (usecs) */
 	const unsigned int	poll_time_us;
-	/* Called during startup */
-	void (*init)(void);
-	/* Called before finish */
-	void (*exit)(void);
 };
 
 #endif

include/linux/serial_s3c.h

···
+/*
+ *  Internal header file for Samsung S3C2410 serial ports (UART0-2)
+ *
+ *  Copyright (C) 2002 Shane Nay ([e-mail])
+ *
+ *  Additional defines, Copyright 2003 Simtec Electronics ([e-mail])
+ *
+ *  Adapted from:
+ *
+ *  Internal header file for MX1ADS serial ports (UART1 & 2)
+ *
+ *  Copyright (C) 2002 Shane Nay ([e-mail])
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+#ifndef __ASM_ARM_REGS_SERIAL_H
+#define __ASM_ARM_REGS_SERIAL_H
+
+#define S3C2410_URXH	  (0x24)
+#define S3C2410_UTXH	  (0x20)
+#define S3C2410_ULCON	  (0x00)
+#define S3C2410_UCON	  (0x04)
+#define S3C2410_UFCON	  (0x08)
+#define S3C2410_UMCON	  (0x0C)
+#define S3C2410_UBRDIV	  (0x28)
+#define S3C2410_UTRSTAT	  (0x10)
+#define S3C2410_UERSTAT	  (0x14)
+#define S3C2410_UFSTAT	  (0x18)
+#define S3C2410_UMSTAT	  (0x1C)
+
+#define S3C2410_LCON_CFGMASK	  ((0xF<<3)|(0x3))
+
+#define S3C2410_LCON_CS5	  (0x0)
+#define S3C2410_LCON_CS6	  (0x1)
+#define S3C2410_LCON_CS7	  (0x2)
+#define S3C2410_LCON_CS8	  (0x3)
+#define S3C2410_LCON_CSMASK	  (0x3)
+
+#define S3C2410_LCON_PNONE	  (0x0)
+#define S3C2410_LCON_PEVEN	  (0x5 << 3)
+#define S3C2410_LCON_PODD	  (0x4 << 3)
+#define S3C2410_LCON_PMASK	  (0x7 << 3)
+
+#define S3C2410_LCON_STOPB	  (1<<2)
+#define S3C2410_LCON_IRM          (1<<6)
+
+#define S3C2440_UCON_CLKMASK	  (3<<10)
+#define S3C2440_UCON_CLKSHIFT	  (10)
+#define S3C2440_UCON_PCLK	  (0<<10)
+#define S3C2440_UCON_UCLK	  (1<<10)
+#define S3C2440_UCON_PCLK2	  (2<<10)
+#define S3C2440_UCON_FCLK	  (3<<10)
+#define S3C2443_UCON_EPLL	  (3<<10)
+
+#define S3C6400_UCON_CLKMASK	(3<<10)
+#define S3C6400_UCON_CLKSHIFT	(10)
+#define S3C6400_UCON_PCLK	(0<<10)
+#define S3C6400_UCON_PCLK2	(2<<10)
+#define S3C6400_UCON_UCLK0	(1<<10)
+#define S3C6400_UCON_UCLK1	(3<<10)
+
+#define S3C2440_UCON2_FCLK_EN	  (1<<15)
+#define S3C2440_UCON0_DIVMASK	  (15 << 12)
+#define S3C2440_UCON1_DIVMASK	  (15 << 12)
+#define S3C2440_UCON2_DIVMASK	  (7 << 12)
+#define S3C2440_UCON_DIVSHIFT	  (12)
+
+#define S3C2412_UCON_CLKMASK	(3<<10)
+#define S3C2412_UCON_CLKSHIFT	(10)
+#define S3C2412_UCON_UCLK	(1<<10)
+#define S3C2412_UCON_USYSCLK	(3<<10)
+#define S3C2412_UCON_PCLK	(0<<10)
+#define S3C2412_UCON_PCLK2	(2<<10)
+
+#define S3C2410_UCON_CLKMASK	(1 << 10)
+#define S3C2410_UCON_CLKSHIFT	(10)
+#define S3C2410_UCON_UCLK	  (1<<10)
+#define S3C2410_UCON_SBREAK	  (1<<4)
+
+#define S3C2410_UCON_TXILEVEL	  (1<<9)
+#define S3C2410_UCON_RXILEVEL	  (1<<8)
+#define S3C2410_UCON_TXIRQMODE	  (1<<2)
+#define S3C2410_UCON_RXIRQMODE	  (1<<0)
+#define S3C2410_UCON_RXFIFO_TOI	  (1<<7)
+#define S3C2443_UCON_RXERR_IRQEN  (1<<6)
+#define S3C2443_UCON_LOOPBACK	  (1<<5)
+
+#define S3C2410_UCON_DEFAULT	  (S3C2410_UCON_TXILEVEL  | \
+				   S3C2410_UCON_RXILEVEL  | \
+				   S3C2410_UCON_TXIRQMODE | \
+				   S3C2410_UCON_RXIRQMODE | \
+				   S3C2410_UCON_RXFIFO_TOI)
+
+#define S3C2410_UFCON_FIFOMODE	  (1<<0)
+#define S3C2410_UFCON_TXTRIG0	  (0<<6)
+#define S3C2410_UFCON_RXTRIG8	  (1<<4)
+#define S3C2410_UFCON_RXTRIG12	  (2<<4)
+
+/* S3C2440 FIFO trigger levels */
+#define S3C2440_UFCON_RXTRIG1	  (0<<4)
+#define S3C2440_UFCON_RXTRIG8	  (1<<4)
+#define S3C2440_UFCON_RXTRIG16	  (2<<4)
+#define S3C2440_UFCON_RXTRIG32	  (3<<4)
+
+#define S3C2440_UFCON_TXTRIG0	  (0<<6)
+#define S3C2440_UFCON_TXTRIG16	  (1<<6)
+#define S3C2440_UFCON_TXTRIG32	  (2<<6)
+#define S3C2440_UFCON_TXTRIG48	  (3<<6)
+
+#define S3C2410_UFCON_RESETBOTH	  (3<<1)
+#define S3C2410_UFCON_RESETTX	  (1<<2)
+#define S3C2410_UFCON_RESETRX	  (1<<1)
+
+#define S3C2410_UFCON_DEFAULT	  (S3C2410_UFCON_FIFOMODE | \
+				   S3C2410_UFCON_TXTRIG0  | \
+				   S3C2410_UFCON_RXTRIG8 )
+
+#define	S3C2410_UMCOM_AFC	  (1<<4)
+#define	S3C2410_UMCOM_RTS_LOW	  (1<<0)
+
+#define S3C2412_UMCON_AFC_63	(0<<5)		/* same as s3c2443 */
+#define S3C2412_UMCON_AFC_56	(1<<5)
+#define S3C2412_UMCON_AFC_48	(2<<5)
+#define S3C2412_UMCON_AFC_40	(3<<5)
+#define S3C2412_UMCON_AFC_32	(4<<5)
+#define S3C2412_UMCON_AFC_24	(5<<5)
+#define S3C2412_UMCON_AFC_16	(6<<5)
+#define S3C2412_UMCON_AFC_8	(7<<5)
+
+#define S3C2410_UFSTAT_TXFULL	  (1<<9)
+#define S3C2410_UFSTAT_RXFULL	  (1<<8)
+#define S3C2410_UFSTAT_TXMASK	  (15<<4)
+#define S3C2410_UFSTAT_TXSHIFT	  (4)
+#define S3C2410_UFSTAT_RXMASK	  (15<<0)
+#define S3C2410_UFSTAT_RXSHIFT	  (0)
+
+/* UFSTAT S3C2443 same as S3C2440 */
+#define S3C2440_UFSTAT_TXFULL	  (1<<14)
+#define S3C2440_UFSTAT_RXFULL	  (1<<6)
+#define S3C2440_UFSTAT_TXSHIFT	  (8)
+#define S3C2440_UFSTAT_RXSHIFT	  (0)
+#define S3C2440_UFSTAT_TXMASK	  (63<<8)
+#define S3C2440_UFSTAT_RXMASK	  (63)
+
+#define S3C2410_UTRSTAT_TXE	  (1<<2)
+#define S3C2410_UTRSTAT_TXFE	  (1<<1)
+#define S3C2410_UTRSTAT_RXDR	  (1<<0)
+
+#define S3C2410_UERSTAT_OVERRUN	  (1<<0)
+#define S3C2410_UERSTAT_FRAME	  (1<<2)
+#define S3C2410_UERSTAT_BREAK	  (1<<3)
+#define S3C2443_UERSTAT_PARITY	  (1<<1)
+
+#define S3C2410_UERSTAT_ANY	  (S3C2410_UERSTAT_OVERRUN | \
+				   S3C2410_UERSTAT_FRAME | \
+				   S3C2410_UERSTAT_BREAK)
+
+#define S3C2410_UMSTAT_CTS	  (1<<0)
+#define S3C2410_UMSTAT_DeltaCTS	  (1<<2)
+
+#define S3C2443_DIVSLOT		  (0x2C)
+
+/* S3C64XX interrupt registers. */
+#define S3C64XX_UINTP		0x30
+#define S3C64XX_UINTSP		0x34
+#define S3C64XX_UINTM		0x38
+
+#define S3C64XX_UINTM_RXD	(0)
+#define S3C64XX_UINTM_TXD	(2)
+#define S3C64XX_UINTM_RXD_MSK	(1 << S3C64XX_UINTM_RXD)
+#define S3C64XX_UINTM_TXD_MSK	(1 << S3C64XX_UINTM_TXD)
+
+/* Following are specific to S5PV210 */
+#define S5PV210_UCON_CLKMASK	(1<<10)
+#define S5PV210_UCON_CLKSHIFT	(10)
+#define S5PV210_UCON_PCLK	(0<<10)
+#define S5PV210_UCON_UCLK	(1<<10)
+
+#define S5PV210_UFCON_TXTRIG0	(0<<8)
+#define S5PV210_UFCON_TXTRIG4	(1<<8)
+#define S5PV210_UFCON_TXTRIG8	(2<<8)
+#define S5PV210_UFCON_TXTRIG16	(3<<8)
+#define S5PV210_UFCON_TXTRIG32	(4<<8)
+#define S5PV210_UFCON_TXTRIG64	(5<<8)
+#define S5PV210_UFCON_TXTRIG128 (6<<8)
+#define S5PV210_UFCON_TXTRIG256 (7<<8)
+
+#define S5PV210_UFCON_RXTRIG1	(0<<4)
+#define S5PV210_UFCON_RXTRIG4	(1<<4)
+#define S5PV210_UFCON_RXTRIG8	(2<<4)
+#define S5PV210_UFCON_RXTRIG16	(3<<4)
+#define S5PV210_UFCON_RXTRIG32	(4<<4)
+#define S5PV210_UFCON_RXTRIG64	(5<<4)
+#define S5PV210_UFCON_RXTRIG128	(6<<4)
+#define S5PV210_UFCON_RXTRIG256	(7<<4)
+
+#define S5PV210_UFSTAT_TXFULL	(1<<24)
+#define S5PV210_UFSTAT_RXFULL	(1<<8)
+#define S5PV210_UFSTAT_TXMASK	(255<<16)
+#define S5PV210_UFSTAT_TXSHIFT	(16)
+#define S5PV210_UFSTAT_RXMASK	(255<<0)
+#define S5PV210_UFSTAT_RXSHIFT	(0)
+
+#define S3C2410_UCON_CLKSEL0	(1 << 0)
+#define S3C2410_UCON_CLKSEL1	(1 << 1)
+#define S3C2410_UCON_CLKSEL2	(1 << 2)
+#define S3C2410_UCON_CLKSEL3	(1 << 3)
+
+/* Default values for s5pv210 UCON and UFCON uart registers */
+#define S5PV210_UCON_DEFAULT	(S3C2410_UCON_TXILEVEL |	\
+				 S3C2410_UCON_RXILEVEL |	\
+				 S3C2410_UCON_TXIRQMODE |	\
+				 S3C2410_UCON_RXIRQMODE |	\
+				 S3C2410_UCON_RXFIFO_TOI |	\
+				 S3C2443_UCON_RXERR_IRQEN)
+
+#define S5PV210_UFCON_DEFAULT	(S3C2410_UFCON_FIFOMODE |	\
+				 S5PV210_UFCON_TXTRIG4 |	\
+				 S5PV210_UFCON_RXTRIG4)
+
+#ifndef __ASSEMBLY__
+
+/* configuration structure for per-machine configurations for the
+ * serial port
+ *
+ * the pointer is setup by the machine specific initialisation from the
+ * arch/arm/mach-s3c2410/ directory.
+*/
+
+struct s3c2410_uartcfg {
+	unsigned char	   hwport;	 /* hardware port number */
+	unsigned char	   unused;
+	unsigned short	   flags;
+	upf_t		   uart_flags;	 /* default uart flags */
+	unsigned int	   clk_sel;
+
+	unsigned int	   has_fracval;
+
+	unsigned long	   ucon;	 /* value of ucon for port */
+	unsigned long	   ulcon;	 /* value of ulcon for port */
+	unsigned long	   ufcon;	 /* value of ufcon for port */
+};
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_ARM_REGS_SERIAL_H */
+

include/linux/tty.h

···
 	int count;
 	struct winsize winsize;		/* termios mutex */
 	unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
-	unsigned char warned:1;
 	unsigned char ctrl_status;	/* ctrl_lock */
 	unsigned int receive_room;	/* Bytes free for queue */
+	int flow_change;
 
 	struct tty_struct *link;
 	struct fasync_struct *fasync;
···
 #define TTY_NO_WRITE_SPLIT 	17	/* Preserve write boundaries to driver */
 #define TTY_HUPPED 		18	/* Post driver->hangup() */
 #define TTY_HUPPING 		21	/* ->hangup() in progress */
+#define TTY_LDISC_HALTED	22	/* Line discipline is halted */
 
 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
+
+/* Values for tty->flow_change */
+#define TTY_THROTTLE_SAFE 1
+#define TTY_UNTHROTTLE_SAFE 2
+
+static inline void __tty_set_flow_change(struct tty_struct *tty, int val)
+{
+	tty->flow_change = val;
+}
+
+static inline void tty_set_flow_change(struct tty_struct *tty, int val)
+{
+	tty->flow_change = val;
+	smp_mb();
+}
 
 #ifdef CONFIG_TTY
 extern void console_init(void);
···
 extern void tty_driver_flush_buffer(struct tty_struct *tty);
 extern void tty_throttle(struct tty_struct *tty);
 extern void tty_unthrottle(struct tty_struct *tty);
+extern int tty_throttle_safe(struct tty_struct *tty);
+extern int tty_unthrottle_safe(struct tty_struct *tty);
 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
 extern void tty_driver_remove_tty(struct tty_driver *driver,
 				  struct tty_struct *tty);
···
 extern void tty_buffer_free_all(struct tty_port *port);
 extern void tty_buffer_flush(struct tty_struct *tty);
 extern void tty_buffer_init(struct tty_port *port);
-extern speed_t tty_get_baud_rate(struct tty_struct *tty);
 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
 						speed_t ibaud, speed_t obaud);
 extern void tty_encode_baud_rate(struct tty_struct *tty,
 						speed_t ibaud, speed_t obaud);
+
+/**
+ *	tty_get_baud_rate	-	get tty bit rates
+ *	@tty: tty to query
+ *
+ *	Returns the baud rate as an integer for this terminal. The
+ *	termios lock must be held by the caller and the terminal bit
+ *	flags may be updated.
+ *
+ *	Locking: none
+ */
+static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
+{
+	return tty_termios_baud_rate(&tty->termios);
+}
+
 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
···
 extern void tty_port_raise_dtr_rts(struct tty_port *port);
 extern void tty_port_lower_dtr_rts(struct tty_port *port);
 extern void tty_port_hangup(struct tty_port *port);
+extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
+extern void tty_port_tty_wakeup(struct tty_port *port);
 extern int tty_port_block_til_ready(struct tty_port *port,
 				struct tty_struct *tty, struct file *filp);
 extern int tty_port_close_start(struct tty_port *port,
···
 extern void tty_ldisc_init(struct tty_struct *tty);
 extern void tty_ldisc_deinit(struct tty_struct *tty);
 extern void tty_ldisc_begin(void);
-/* This last one is just for the tty layer internals and shouldn't be used elsewhere */
-extern void tty_ldisc_enable(struct tty_struct *tty);
 
 
 /* n_tty.c */

include/linux/tty_ldisc.h

···
  *
  * int	(*open)(struct tty_struct *);
  *
- * 	This function is called when the line discipline is associated
- * 	with the tty.  The line discipline can use this as an
- * 	opportunity to initialize any state needed by the ldisc routines.
- * 
+ *	This function is called when the line discipline is associated
+ *	with the tty.  The line discipline can use this as an
+ *	opportunity to initialize any state needed by the ldisc routines.
+ *
  * void	(*close)(struct tty_struct *);
  *
  *	This function is called when the line discipline is being
- * 	shutdown, either because the tty is being closed or because
- * 	the tty is being changed to use a new line discipline
- * 
+ *	shutdown, either because the tty is being closed or because
+ *	the tty is being changed to use a new line discipline
+ *
  * void	(*flush_buffer)(struct tty_struct *tty);
  *
- * 	This function instructs the line discipline to clear its
- * 	buffers of any input characters it may have queued to be
- * 	delivered to the user mode process.
- * 
+ *	This function instructs the line discipline to clear its
+ *	buffers of any input characters it may have queued to be
+ *	delivered to the user mode process.
+ *
  * ssize_t (*chars_in_buffer)(struct tty_struct *tty);
  *
- * 	This function returns the number of input characters the line
+ *	This function returns the number of input characters the line
  *	discipline may have queued up to be delivered to the user mode
  *	process.
- * 
+ *
  * ssize_t (*read)(struct tty_struct * tty, struct file * file,
  *		   unsigned char * buf, size_t nr);
  *
- * 	This function is called when the user requests to read from
- * 	the tty.  The line discipline will return whatever characters
- * 	it has buffered up for the user.  If this function is not
- * 	defined, the user will receive an EIO error.
- * 
- * ssize_t (*write)(struct tty_struct * tty, struct file * file,
- * 		    const unsigned char * buf, size_t nr);
+ *	This function is called when the user requests to read from
+ *	the tty.  The line discipline will return whatever characters
+ *	it has buffered up for the user.  If this function is not
+ *	defined, the user will receive an EIO error.
  *
- * 	This function is called when the user requests to write to the
- * 	tty.  The line discipline will deliver the characters to the
- * 	low-level tty device for transmission, optionally performing
- * 	some processing on the characters first.  If this function is
- * 	not defined, the user will receive an EIO error.
- * 
+ * ssize_t (*write)(struct tty_struct * tty, struct file * file,
+ *		    const unsigned char * buf, size_t nr);
+ *
+ *	This function is called when the user requests to write to the
+ *	tty.  The line discipline will deliver the characters to the
+ *	low-level tty device for transmission, optionally performing
+ *	some processing on the characters first.  If this function is
+ *	not defined, the user will receive an EIO error.
+ *
  * int	(*ioctl)(struct tty_struct * tty, struct file * file,
- * 		 unsigned int cmd, unsigned long arg);
+ *		 unsigned int cmd, unsigned long arg);
  *
  *	This function is called when the user requests an ioctl which
- * 	is not handled by the tty layer or the low-level tty driver.
- * 	It is intended for ioctls which affect line discpline
- * 	operation.  Note that the search order for ioctls is (1) tty
- * 	layer, (2) tty low-level driver, (3) line discpline.  So a
- * 	low-level driver can "grab" an ioctl request before the line
- * 	discpline has a chance to see it.
- * 
- * long	(*compat_ioctl)(struct tty_struct * tty, struct file * file,
- * 		        unsigned int cmd, unsigned long arg);
+ *	is not handled by the tty layer or the low-level tty driver.
+ *	It is intended for ioctls which affect line discpline
+ *	operation.  Note that the search order for ioctls is (1) tty
+ *	layer, (2) tty low-level driver, (3) line discpline.  So a
+ *	low-level driver can "grab" an ioctl request before the line
+ *	discpline has a chance to see it.
  *
- *      Process ioctl calls from 32-bit process on 64-bit system
+ * long	(*compat_ioctl)(struct tty_struct * tty, struct file * file,
+ *		        unsigned int cmd, unsigned long arg);
+ *
+ *	Process ioctl calls from 32-bit process on 64-bit system
  *
  * void	(*set_termios)(struct tty_struct *tty, struct ktermios * old);
  *
- * 	This function notifies the line discpline that a change has
- * 	been made to the termios structure.
- * 
- * int	(*poll)(struct tty_struct * tty, struct file * file,
- * 		  poll_table *wait);
+ *	This function notifies the line discpline that a change has
+ *	been made to the termios structure.
  *
- * 	This function is called when a user attempts to select/poll on a
- * 	tty device.  It is solely the responsibility of the line
- * 	discipline to handle poll requests.
+ * int	(*poll)(struct tty_struct * tty, struct file * file,
+ *		  poll_table *wait);
+ *
+ *	This function is called when a user attempts to select/poll on a
+ *	tty device.  It is solely the responsibility of the line
+ *	discipline to handle poll requests.
  *
  * void	(*receive_buf)(struct tty_struct *, const unsigned char *cp,
- * 		       char *fp, int count);
+ *		       char *fp, int count);
  *
- * 	This function is called by the low-level tty driver to send
- * 	characters received by the hardware to the line discpline for
- * 	processing.  <cp> is a pointer to the buffer of input
- * 	character received by the device.  <fp> is a pointer to a
- * 	pointer of flag bytes which indicate whether a character was
- * 	received with a parity error, etc.
- * 
+ *	This function is called by the low-level tty driver to send
+ *	characters received by the hardware to the line discpline for
+ *	processing.  <cp> is a pointer to the buffer of input
+ *	character received by the device.  <fp> is a pointer to a
+ *	pointer of flag bytes which indicate whether a character was
+ *	received with a parity error, etc.
+ *
  * void	(*write_wakeup)(struct tty_struct *);
  *
- * 	This function is called by the low-level tty driver to signal
- * 	that line discpline should try to send more characters to the
- * 	low-level driver for transmission.  If the line discpline does
- * 	not have any more data to send, it can just return.
+ *	This function is called by the low-level tty driver to signal
+ *	that line discpline should try to send more characters to the
+ *	low-level driver for transmission.  If the line discpline does
+ *	not have any more data to send, it can just return.
  *
  * int (*hangup)(struct tty_struct *)
  *
···
 	char	*name;
 	int	num;
 	int	flags;
-	
+
 	/*
 	 * The following routines are called from above.
 	 */
···
 	void	(*close)(struct tty_struct *);
 	void	(*flush_buffer)(struct tty_struct *tty);
 	ssize_t	(*chars_in_buffer)(struct tty_struct *tty);
-	ssize_t	(*read)(struct tty_struct * tty, struct file * file,
-			unsigned char __user * buf, size_t nr);
-	ssize_t	(*write)(struct tty_struct * tty, struct file * file,
-			 const unsigned char * buf, size_t nr);	
-	int	(*ioctl)(struct tty_struct * tty, struct file * file,
+	ssize_t	(*read)(struct tty_struct *tty, struct file *file,
+			unsigned char __user *buf, size_t nr);
+	ssize_t	(*write)(struct tty_struct *tty, struct file *file,
+			 const unsigned char *buf, size_t nr);
+	int	(*ioctl)(struct tty_struct *tty, struct file *file,
 			 unsigned int cmd, unsigned long arg);
-	long	(*compat_ioctl)(struct tty_struct * tty, struct file * file,
+	long	(*compat_ioctl)(struct tty_struct *tty, struct file *file,
 				unsigned int cmd, unsigned long arg);
-	void	(*set_termios)(struct tty_struct *tty, struct ktermios * old);
+	void	(*set_termios)(struct tty_struct *tty, struct ktermios *old);
 	unsigned int (*poll)(struct tty_struct *, struct file *,
 			     struct poll_table_struct *);
 	int	(*hangup)(struct tty_struct *tty);
-	
+
 	/*
 	 * The following routines are called from below.
 	 */
···
 	void	(*dcd_change)(struct tty_struct *, unsigned int);
 
 	struct  module *owner;
-	
+
 	int refcount;
 };
 

net/irda/ircomm/ircomm_tty.c

···
 	spin_unlock_irqrestore(&port->lock, flags);
 
 	while (1) {
-		if (tty->termios.c_cflag & CBAUD)
+		if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
 			tty_port_raise_dtr_rts(port);
 
 		set_current_state(TASK_INTERRUPTIBLE);

net/irda/ircomm/ircomm_tty_attach.c

···
 			self->settings.dce = IRCOMM_DELTA_CD;
 			ircomm_tty_check_modem_status(self);
 		} else {
-			struct tty_struct *tty = tty_port_tty_get(&self->port);
 			IRDA_DEBUG(0, "%s(), hanging up!\n", __func__ );
-			if (tty) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			tty_port_tty_hangup(&self->port, false);
 		}
 		break;
 	default: