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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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/* * Note: Although this driver assumes a 16550A-like UART implementation, * it is not possible to leverage the common 8250/16550 driver, nor the * core UART infrastructure, as they assumes direct access to the hardware * registers, often under a spinlock. This is not possible in the SDIO * context as SDIO access functions must be able to sleep. * * Because we need to lock the SDIO host to ensure an exclusive access to * the card, we simply rely on that lock to also prevent and serialize * concurrent access to the same port. */
#include <linux/module.h>#include <linux/init.h>#include <linux/kernel.h>#include <linux/sched.h>#include <linux/mutex.h>#include <linux/seq_file.h>#include <linux/serial.h>#include <linux/serial_reg.h>#include <linux/circ_buf.h>#include <linux/tty.h>#include <linux/tty_flip.h>#include <linux/kfifo.h>#include <linux/slab.h>
#include <linux/mmc/core.h>#include <linux/mmc/card.h>#include <linux/mmc/sdio_func.h>#include <linux/mmc/sdio_ids.h>
#define UART_NR 8 /* Number of UARTs this driver can handle */
#define FIFO_SIZE PAGE_SIZE#define WAKEUP_CHARS 256
struct uart_icount { __u32 cts; __u32 dsr; __u32 rng; __u32 dcd; __u32 rx; __u32 tx; __u32 frame; __u32 overrun; __u32 parity; __u32 brk;};
struct sdio_uart_port { struct tty_port port; unsigned int index; struct sdio_func *func; struct mutex func_lock; struct task_struct *in_sdio_uart_irq; unsigned int regs_offset; struct kfifo xmit_fifo; spinlock_t write_lock; struct uart_icount icount; unsigned int uartclk; unsigned int mctrl; unsigned int rx_mctrl; unsigned int read_status_mask; unsigned int ignore_status_mask; unsigned char x_char; unsigned char ier; unsigned char lcr;};
static struct sdio_uart_port *sdio_uart_table[UART_NR];static DEFINE_SPINLOCK(sdio_uart_table_lock);
static int sdio_uart_add_port(struct sdio_uart_port *port){ int index, ret = -EBUSY;
mutex_init(&port->func_lock); spin_lock_init(&port->write_lock); if (kfifo_alloc(&port->xmit_fifo, FIFO_SIZE, GFP_KERNEL)) return -ENOMEM;
spin_lock(&sdio_uart_table_lock); for (index = 0; index < UART_NR; index++) { if (!sdio_uart_table[index]) { port->index = index; sdio_uart_table[index] = port; ret = 0; break; } } spin_unlock(&sdio_uart_table_lock);
if (ret) kfifo_free(&port->xmit_fifo);
return ret;}
static struct sdio_uart_port *sdio_uart_port_get(unsigned index){ struct sdio_uart_port *port;
if (index >= UART_NR) return NULL;
spin_lock(&sdio_uart_table_lock); port = sdio_uart_table[index]; if (port) tty_port_get(&port->port); spin_unlock(&sdio_uart_table_lock);
return port;}
static void sdio_uart_port_put(struct sdio_uart_port *port){ tty_port_put(&port->port);}
static void sdio_uart_port_remove(struct sdio_uart_port *port){ struct sdio_func *func;
spin_lock(&sdio_uart_table_lock); sdio_uart_table[port->index] = NULL; spin_unlock(&sdio_uart_table_lock);
/* * We're killing a port that potentially still is in use by * the tty layer. Be careful to prevent any further access * to the SDIO function and arrange for the tty layer to * give up on that port ASAP. * Beware: the lock ordering is critical. */ mutex_lock(&port->port.mutex); mutex_lock(&port->func_lock); func = port->func; sdio_claim_host(func); port->func = NULL; mutex_unlock(&port->func_lock); /* tty_hangup is async so is this safe as is ?? */ tty_port_tty_hangup(&port->port, false); mutex_unlock(&port->port.mutex); sdio_release_irq(func); sdio_disable_func(func); sdio_release_host(func);
sdio_uart_port_put(port);}
static int sdio_uart_claim_func(struct sdio_uart_port *port){ mutex_lock(&port->func_lock); if (unlikely(!port->func)) { mutex_unlock(&port->func_lock); return -ENODEV; } if (likely(port->in_sdio_uart_irq != current)) sdio_claim_host(port->func); mutex_unlock(&port->func_lock); return 0;}
static inline void sdio_uart_release_func(struct sdio_uart_port *port){ if (likely(port->in_sdio_uart_irq != current)) sdio_release_host(port->func);}
static inline u8 sdio_in(struct sdio_uart_port *port, int offset){ return sdio_readb(port->func, port->regs_offset + offset, NULL);}
static inline void sdio_out(struct sdio_uart_port *port, int offset, int value){ sdio_writeb(port->func, value, port->regs_offset + offset, NULL);}
static unsigned int sdio_uart_get_mctrl(struct sdio_uart_port *port){ unsigned int ret; u8 status;
/* FIXME: What stops this losing the delta bits and breaking sdio_uart_check_modem_status ? */ status = sdio_in(port, UART_MSR);
ret = 0; if (status & UART_MSR_DCD) ret |= TIOCM_CAR; if (status & UART_MSR_RI) ret |= TIOCM_RNG; if (status & UART_MSR_DSR) ret |= TIOCM_DSR; if (status & UART_MSR_CTS) ret |= TIOCM_CTS; return ret;}
static void sdio_uart_write_mctrl(struct sdio_uart_port *port, unsigned int mctrl){ unsigned char mcr = 0;
if (mctrl & TIOCM_RTS) mcr |= UART_MCR_RTS; if (mctrl & TIOCM_DTR) mcr |= UART_MCR_DTR; if (mctrl & TIOCM_OUT1) mcr |= UART_MCR_OUT1; if (mctrl & TIOCM_OUT2) mcr |= UART_MCR_OUT2; if (mctrl & TIOCM_LOOP) mcr |= UART_MCR_LOOP;
sdio_out(port, UART_MCR, mcr);}
static inline void sdio_uart_update_mctrl(struct sdio_uart_port *port, unsigned int set, unsigned int clear){ unsigned int old;
old = port->mctrl; port->mctrl = (old & ~clear) | set; if (old != port->mctrl) sdio_uart_write_mctrl(port, port->mctrl);}
#define sdio_uart_set_mctrl(port, x) sdio_uart_update_mctrl(port, x, 0)#define sdio_uart_clear_mctrl(port, x) sdio_uart_update_mctrl(port, 0, x)
static void sdio_uart_change_speed(struct sdio_uart_port *port, struct ktermios *termios, const struct ktermios *old){ unsigned char cval, fcr = 0; unsigned int baud, quot;
cval = UART_LCR_WLEN(tty_get_char_size(termios->c_cflag));
if (termios->c_cflag & CSTOPB) cval |= UART_LCR_STOP; if (termios->c_cflag & PARENB) cval |= UART_LCR_PARITY; if (!(termios->c_cflag & PARODD)) cval |= UART_LCR_EPAR;
for (;;) { baud = tty_termios_baud_rate(termios); if (baud == 0) baud = 9600; /* Special case: B0 rate. */ if (baud <= port->uartclk) break; /* * Oops, the quotient was zero. Try again with the old * baud rate if possible, otherwise default to 9600. */ termios->c_cflag &= ~CBAUD; if (old) { termios->c_cflag |= old->c_cflag & CBAUD; old = NULL; } else termios->c_cflag |= B9600; } quot = (2 * port->uartclk + baud) / (2 * baud);
if (baud < 2400) fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1; else fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10;
port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR; if (termios->c_iflag & INPCK) port->read_status_mask |= UART_LSR_FE | UART_LSR_PE; if (termios->c_iflag & (BRKINT | PARMRK)) port->read_status_mask |= UART_LSR_BI;
/* * Characters to ignore */ port->ignore_status_mask = 0; if (termios->c_iflag & IGNPAR) port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE; if (termios->c_iflag & IGNBRK) { port->ignore_status_mask |= UART_LSR_BI; /* * If we're ignoring parity and break indicators, * ignore overruns too (for real raw support). */ if (termios->c_iflag & IGNPAR) port->ignore_status_mask |= UART_LSR_OE; }
/* * ignore all characters if CREAD is not set */ if ((termios->c_cflag & CREAD) == 0) port->ignore_status_mask |= UART_LSR_DR;
/* * CTS flow control flag and modem status interrupts */ port->ier &= ~UART_IER_MSI; if ((termios->c_cflag & CRTSCTS) || !(termios->c_cflag & CLOCAL)) port->ier |= UART_IER_MSI;
port->lcr = cval;
sdio_out(port, UART_IER, port->ier); sdio_out(port, UART_LCR, cval | UART_LCR_DLAB); sdio_out(port, UART_DLL, quot & 0xff); sdio_out(port, UART_DLM, quot >> 8); sdio_out(port, UART_LCR, cval); sdio_out(port, UART_FCR, fcr);
sdio_uart_write_mctrl(port, port->mctrl);}
static void sdio_uart_start_tx(struct sdio_uart_port *port){ if (!(port->ier & UART_IER_THRI)) { port->ier |= UART_IER_THRI; sdio_out(port, UART_IER, port->ier); }}
static void sdio_uart_stop_tx(struct sdio_uart_port *port){ if (port->ier & UART_IER_THRI) { port->ier &= ~UART_IER_THRI; sdio_out(port, UART_IER, port->ier); }}
static void sdio_uart_stop_rx(struct sdio_uart_port *port){ port->ier &= ~UART_IER_RLSI; port->read_status_mask &= ~UART_LSR_DR; sdio_out(port, UART_IER, port->ier);}
static void sdio_uart_receive_chars(struct sdio_uart_port *port, u8 *status){ int max_count = 256;
do { u8 ch = sdio_in(port, UART_RX); u8 flag = TTY_NORMAL; port->icount.rx++;
if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE | UART_LSR_FE | UART_LSR_OE))) { /* * For statistics only */ if (*status & UART_LSR_BI) { *status &= ~(UART_LSR_FE | UART_LSR_PE); port->icount.brk++; } else if (*status & UART_LSR_PE) port->icount.parity++; else if (*status & UART_LSR_FE) port->icount.frame++; if (*status & UART_LSR_OE) port->icount.overrun++;
/* * Mask off conditions which should be ignored. */ *status &= port->read_status_mask; if (*status & UART_LSR_BI) flag = TTY_BREAK; else if (*status & UART_LSR_PE) flag = TTY_PARITY; else if (*status & UART_LSR_FE) flag = TTY_FRAME; }
if ((*status & port->ignore_status_mask & ~UART_LSR_OE) == 0) tty_insert_flip_char(&port->port, ch, flag);
/* * Overrun is special. Since it's reported immediately, * it doesn't affect the current character. */ if (*status & ~port->ignore_status_mask & UART_LSR_OE) tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
*status = sdio_in(port, UART_LSR); } while ((*status & UART_LSR_DR) && (max_count-- > 0));
tty_flip_buffer_push(&port->port);}
static void sdio_uart_transmit_chars(struct sdio_uart_port *port){ struct kfifo *xmit = &port->xmit_fifo; int count; struct tty_struct *tty; u8 iobuf[16]; int len;
if (port->x_char) { sdio_out(port, UART_TX, port->x_char); port->icount.tx++; port->x_char = 0; return; }
tty = tty_port_tty_get(&port->port);
if (tty == NULL || !kfifo_len(xmit) || tty->flow.stopped || tty->hw_stopped) { sdio_uart_stop_tx(port); tty_kref_put(tty); return; }
len = kfifo_out_locked(xmit, iobuf, 16, &port->write_lock); for (count = 0; count < len; count++) { sdio_out(port, UART_TX, iobuf[count]); port->icount.tx++; }
len = kfifo_len(xmit); if (len < WAKEUP_CHARS) { tty_wakeup(tty); if (len == 0) sdio_uart_stop_tx(port); } tty_kref_put(tty);}
static void sdio_uart_check_modem_status(struct sdio_uart_port *port){ struct tty_struct *tty; u8 status;
status = sdio_in(port, UART_MSR);
if ((status & UART_MSR_ANY_DELTA) == 0) return;
if (status & UART_MSR_TERI) port->icount.rng++; if (status & UART_MSR_DDSR) port->icount.dsr++; if (status & UART_MSR_DDCD) { port->icount.dcd++; /* DCD raise - wake for open */ if (status & UART_MSR_DCD) wake_up_interruptible(&port->port.open_wait); else { /* DCD drop - hang up if tty attached */ tty_port_tty_hangup(&port->port, false); } } if (status & UART_MSR_DCTS) { port->icount.cts++; tty = tty_port_tty_get(&port->port); if (tty && C_CRTSCTS(tty)) { bool cts = status & UART_MSR_CTS; if (tty->hw_stopped) { if (cts) { tty->hw_stopped = false; sdio_uart_start_tx(port); tty_wakeup(tty); } } else { if (!cts) { tty->hw_stopped = true; sdio_uart_stop_tx(port); } } } tty_kref_put(tty); }}
/* * This handles the interrupt from one port. */static void sdio_uart_irq(struct sdio_func *func){ struct sdio_uart_port *port = sdio_get_drvdata(func); u8 iir, lsr;
/* * In a few places sdio_uart_irq() is called directly instead of * waiting for the actual interrupt to be raised and the SDIO IRQ * thread scheduled in order to reduce latency. However, some * interaction with the tty core may end up calling us back * (serial echo, flow control, etc.) through those same places * causing undesirable effects. Let's stop the recursion here. */ if (unlikely(port->in_sdio_uart_irq == current)) return;
iir = sdio_in(port, UART_IIR); if (iir & UART_IIR_NO_INT) return;
port->in_sdio_uart_irq = current; lsr = sdio_in(port, UART_LSR); if (lsr & UART_LSR_DR) sdio_uart_receive_chars(port, &lsr); sdio_uart_check_modem_status(port); if (lsr & UART_LSR_THRE) sdio_uart_transmit_chars(port); port->in_sdio_uart_irq = NULL;}
static bool uart_carrier_raised(struct tty_port *tport){ struct sdio_uart_port *port = container_of(tport, struct sdio_uart_port, port); unsigned int ret = sdio_uart_claim_func(port); if (ret) /* Missing hardware shouldn't block for carrier */ return 1; ret = sdio_uart_get_mctrl(port); sdio_uart_release_func(port);
return ret & TIOCM_CAR;}
/** * uart_dtr_rts - port helper to set uart signals * @tport: tty port to be updated * @active: set to turn on DTR/RTS * * Called by the tty port helpers when the modem signals need to be * adjusted during an open, close and hangup. */
static void uart_dtr_rts(struct tty_port *tport, bool active){ struct sdio_uart_port *port = container_of(tport, struct sdio_uart_port, port); int ret = sdio_uart_claim_func(port); if (ret) return; if (!active) sdio_uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS); else sdio_uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS); sdio_uart_release_func(port);}
/** * sdio_uart_activate - start up hardware * @tport: tty port to activate * @tty: tty bound to this port * * Activate a tty port. The port locking guarantees us this will be * run exactly once per set of opens, and if successful will see the * shutdown method run exactly once to match. Start up and shutdown are * protected from each other by the internal locking and will not run * at the same time even during a hangup event. * * If we successfully start up the port we take an extra kref as we * will keep it around until shutdown when the kref is dropped. */
static int sdio_uart_activate(struct tty_port *tport, struct tty_struct *tty){ struct sdio_uart_port *port = container_of(tport, struct sdio_uart_port, port); int ret;
/* * Set the TTY IO error marker - we will only clear this * once we have successfully opened the port. */ set_bit(TTY_IO_ERROR, &tty->flags);
kfifo_reset(&port->xmit_fifo);
ret = sdio_uart_claim_func(port); if (ret) return ret; ret = sdio_enable_func(port->func); if (ret) goto err1; ret = sdio_claim_irq(port->func, sdio_uart_irq); if (ret) goto err2;
/* * Clear the FIFO buffers and disable them. * (they will be reenabled in sdio_change_speed()) */ sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO); sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); sdio_out(port, UART_FCR, 0);
/* * Clear the interrupt registers. */ (void) sdio_in(port, UART_LSR); (void) sdio_in(port, UART_RX); (void) sdio_in(port, UART_IIR); (void) sdio_in(port, UART_MSR);
/* * Now, initialize the UART */ sdio_out(port, UART_LCR, UART_LCR_WLEN8);
port->ier = UART_IER_RLSI|UART_IER_RDI|UART_IER_RTOIE|UART_IER_UUE; port->mctrl = TIOCM_OUT2;
sdio_uart_change_speed(port, &tty->termios, NULL);
if (C_BAUD(tty)) sdio_uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR);
if (C_CRTSCTS(tty)) if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS)) tty->hw_stopped = true;
clear_bit(TTY_IO_ERROR, &tty->flags);
/* Kick the IRQ handler once while we're still holding the host lock */ sdio_uart_irq(port->func);
sdio_uart_release_func(port); return 0;
err2: sdio_disable_func(port->func);err1: sdio_uart_release_func(port); return ret;}
/** * sdio_uart_shutdown - stop hardware * @tport: tty port to shut down * * Deactivate a tty port. The port locking guarantees us this will be * run only if a successful matching activate already ran. The two are * protected from each other by the internal locking and will not run * at the same time even during a hangup event. */
static void sdio_uart_shutdown(struct tty_port *tport){ struct sdio_uart_port *port = container_of(tport, struct sdio_uart_port, port); int ret;
ret = sdio_uart_claim_func(port); if (ret) return;
sdio_uart_stop_rx(port);
/* Disable interrupts from this port */ sdio_release_irq(port->func); port->ier = 0; sdio_out(port, UART_IER, 0);
sdio_uart_clear_mctrl(port, TIOCM_OUT2);
/* Disable break condition and FIFOs. */ port->lcr &= ~UART_LCR_SBC; sdio_out(port, UART_LCR, port->lcr); sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); sdio_out(port, UART_FCR, 0);
sdio_disable_func(port->func);
sdio_uart_release_func(port);}
static void sdio_uart_port_destroy(struct tty_port *tport){ struct sdio_uart_port *port = container_of(tport, struct sdio_uart_port, port); kfifo_free(&port->xmit_fifo); kfree(port);}
/** * sdio_uart_install - install method * @driver: the driver in use (sdio_uart in our case) * @tty: the tty being bound * * Look up and bind the tty and the driver together. Initialize * any needed private data (in our case the termios) */
static int sdio_uart_install(struct tty_driver *driver, struct tty_struct *tty){ int idx = tty->index; struct sdio_uart_port *port = sdio_uart_port_get(idx); int ret = tty_standard_install(driver, tty);
if (ret == 0) /* This is the ref sdio_uart_port get provided */ tty->driver_data = port; else sdio_uart_port_put(port); return ret;}
/** * sdio_uart_cleanup - called on the last tty kref drop * @tty: the tty being destroyed * * Called asynchronously when the last reference to the tty is dropped. * We cannot destroy the tty->driver_data port kref until this point */
static void sdio_uart_cleanup(struct tty_struct *tty){ struct sdio_uart_port *port = tty->driver_data; tty->driver_data = NULL; /* Bug trap */ sdio_uart_port_put(port);}
/* * Open/close/hangup is now entirely boilerplate */
static int sdio_uart_open(struct tty_struct *tty, struct file *filp){ struct sdio_uart_port *port = tty->driver_data; return tty_port_open(&port->port, tty, filp);}
static void sdio_uart_close(struct tty_struct *tty, struct file * filp){ struct sdio_uart_port *port = tty->driver_data; tty_port_close(&port->port, tty, filp);}
static void sdio_uart_hangup(struct tty_struct *tty){ struct sdio_uart_port *port = tty->driver_data; tty_port_hangup(&port->port);}
static ssize_t sdio_uart_write(struct tty_struct *tty, const u8 *buf, size_t count){ struct sdio_uart_port *port = tty->driver_data; int ret;
if (!port->func) return -ENODEV;
ret = kfifo_in_locked(&port->xmit_fifo, buf, count, &port->write_lock); if (!(port->ier & UART_IER_THRI)) { int err = sdio_uart_claim_func(port); if (!err) { sdio_uart_start_tx(port); sdio_uart_irq(port->func); sdio_uart_release_func(port); } else ret = err; }
return ret;}
static unsigned int sdio_uart_write_room(struct tty_struct *tty){ struct sdio_uart_port *port = tty->driver_data; return FIFO_SIZE - kfifo_len(&port->xmit_fifo);}
static unsigned int sdio_uart_chars_in_buffer(struct tty_struct *tty){ struct sdio_uart_port *port = tty->driver_data; return kfifo_len(&port->xmit_fifo);}
static void sdio_uart_send_xchar(struct tty_struct *tty, u8 ch){ struct sdio_uart_port *port = tty->driver_data;
port->x_char = ch; if (ch && !(port->ier & UART_IER_THRI)) { if (sdio_uart_claim_func(port) != 0) return; sdio_uart_start_tx(port); sdio_uart_irq(port->func); sdio_uart_release_func(port); }}
static void sdio_uart_throttle(struct tty_struct *tty){ struct sdio_uart_port *port = tty->driver_data;
if (!I_IXOFF(tty) && !C_CRTSCTS(tty)) return;
if (sdio_uart_claim_func(port) != 0) return;
if (I_IXOFF(tty)) { port->x_char = STOP_CHAR(tty); sdio_uart_start_tx(port); }
if (C_CRTSCTS(tty)) sdio_uart_clear_mctrl(port, TIOCM_RTS);
sdio_uart_irq(port->func); sdio_uart_release_func(port);}
static void sdio_uart_unthrottle(struct tty_struct *tty){ struct sdio_uart_port *port = tty->driver_data;
if (!I_IXOFF(tty) && !C_CRTSCTS(tty)) return;
if (sdio_uart_claim_func(port) != 0) return;
if (I_IXOFF(tty)) { if (port->x_char) { port->x_char = 0; } else { port->x_char = START_CHAR(tty); sdio_uart_start_tx(port); } }
if (C_CRTSCTS(tty)) sdio_uart_set_mctrl(port, TIOCM_RTS);
sdio_uart_irq(port->func); sdio_uart_release_func(port);}
static void sdio_uart_set_termios(struct tty_struct *tty, const struct ktermios *old_termios){ struct sdio_uart_port *port = tty->driver_data; unsigned int cflag = tty->termios.c_cflag;
if (sdio_uart_claim_func(port) != 0) return;
sdio_uart_change_speed(port, &tty->termios, old_termios);
/* Handle transition to B0 status */ if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD)) sdio_uart_clear_mctrl(port, TIOCM_RTS | TIOCM_DTR);
/* Handle transition away from B0 status */ if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) { unsigned int mask = TIOCM_DTR; if (!(cflag & CRTSCTS) || !tty_throttled(tty)) mask |= TIOCM_RTS; sdio_uart_set_mctrl(port, mask); }
/* Handle turning off CRTSCTS */ if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) { tty->hw_stopped = false; sdio_uart_start_tx(port); }
/* Handle turning on CRTSCTS */ if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) { if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS)) { tty->hw_stopped = true; sdio_uart_stop_tx(port); } }
sdio_uart_release_func(port);}
static int sdio_uart_break_ctl(struct tty_struct *tty, int break_state){ struct sdio_uart_port *port = tty->driver_data; int result;
result = sdio_uart_claim_func(port); if (result != 0) return result;
if (break_state == -1) port->lcr |= UART_LCR_SBC; else port->lcr &= ~UART_LCR_SBC; sdio_out(port, UART_LCR, port->lcr);
sdio_uart_release_func(port); return 0;}
static int sdio_uart_tiocmget(struct tty_struct *tty){ struct sdio_uart_port *port = tty->driver_data; int result;
result = sdio_uart_claim_func(port); if (!result) { result = port->mctrl | sdio_uart_get_mctrl(port); sdio_uart_release_func(port); }
return result;}
static int sdio_uart_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear){ struct sdio_uart_port *port = tty->driver_data; int result;
result = sdio_uart_claim_func(port); if (!result) { sdio_uart_update_mctrl(port, set, clear); sdio_uart_release_func(port); }
return result;}
static int sdio_uart_proc_show(struct seq_file *m, void *v){ int i;
seq_printf(m, "serinfo:1.0 driver%s%s revision:%s\n", "", "", ""); for (i = 0; i < UART_NR; i++) { struct sdio_uart_port *port = sdio_uart_port_get(i); if (port) { seq_printf(m, "%d: uart:SDIO", i); if (capable(CAP_SYS_ADMIN)) { seq_printf(m, " tx:%d rx:%d", port->icount.tx, port->icount.rx); if (port->icount.frame) seq_printf(m, " fe:%d", port->icount.frame); if (port->icount.parity) seq_printf(m, " pe:%d", port->icount.parity); if (port->icount.brk) seq_printf(m, " brk:%d", port->icount.brk); if (port->icount.overrun) seq_printf(m, " oe:%d", port->icount.overrun); if (port->icount.cts) seq_printf(m, " cts:%d", port->icount.cts); if (port->icount.dsr) seq_printf(m, " dsr:%d", port->icount.dsr); if (port->icount.rng) seq_printf(m, " rng:%d", port->icount.rng); if (port->icount.dcd) seq_printf(m, " dcd:%d", port->icount.dcd); } sdio_uart_port_put(port); seq_putc(m, '\n'); } } return 0;}
static const struct tty_port_operations sdio_uart_port_ops = { .dtr_rts = uart_dtr_rts, .carrier_raised = uart_carrier_raised, .shutdown = sdio_uart_shutdown, .activate = sdio_uart_activate, .destruct = sdio_uart_port_destroy,};
static const struct tty_operations sdio_uart_ops = { .open = sdio_uart_open, .close = sdio_uart_close, .write = sdio_uart_write, .write_room = sdio_uart_write_room, .chars_in_buffer = sdio_uart_chars_in_buffer, .send_xchar = sdio_uart_send_xchar, .throttle = sdio_uart_throttle, .unthrottle = sdio_uart_unthrottle, .set_termios = sdio_uart_set_termios, .hangup = sdio_uart_hangup, .break_ctl = sdio_uart_break_ctl, .tiocmget = sdio_uart_tiocmget, .tiocmset = sdio_uart_tiocmset, .install = sdio_uart_install, .cleanup = sdio_uart_cleanup, .proc_show = sdio_uart_proc_show,};
static struct tty_driver *sdio_uart_tty_driver;
static int sdio_uart_probe(struct sdio_func *func, const struct sdio_device_id *id){ struct sdio_uart_port *port; int ret;
port = kzalloc_obj(struct sdio_uart_port); if (!port) return -ENOMEM;
if (func->class == SDIO_CLASS_UART) { pr_warn("%s: need info on UART class basic setup\n", sdio_func_id(func)); kfree(port); return -ENOSYS; } else if (func->class == SDIO_CLASS_GPS) { /* * We need tuple 0x91. It contains SUBTPL_SIOREG * and SUBTPL_RCVCAPS. */ struct sdio_func_tuple *tpl; for (tpl = func->tuples; tpl; tpl = tpl->next) { if (tpl->code != 0x91) continue; if (tpl->size < 10) continue; if (tpl->data[1] == 0) /* SUBTPL_SIOREG */ break; } if (!tpl) { pr_warn("%s: can't find tuple 0x91 subtuple 0 (SUBTPL_SIOREG) for GPS class\n", sdio_func_id(func)); kfree(port); return -EINVAL; } pr_debug("%s: Register ID = 0x%02x, Exp ID = 0x%02x\n", sdio_func_id(func), tpl->data[2], tpl->data[3]); port->regs_offset = (tpl->data[4] << 0) | (tpl->data[5] << 8) | (tpl->data[6] << 16); pr_debug("%s: regs offset = 0x%x\n", sdio_func_id(func), port->regs_offset); port->uartclk = tpl->data[7] * 115200; if (port->uartclk == 0) port->uartclk = 115200; pr_debug("%s: clk %d baudcode %u 4800-div %u\n", sdio_func_id(func), port->uartclk, tpl->data[7], tpl->data[8] | (tpl->data[9] << 8)); } else { kfree(port); return -EINVAL; }
port->func = func; sdio_set_drvdata(func, port); tty_port_init(&port->port); port->port.ops = &sdio_uart_port_ops;
ret = sdio_uart_add_port(port); if (ret) { kfree(port); } else { struct device *dev; dev = tty_port_register_device(&port->port, sdio_uart_tty_driver, port->index, &func->dev); if (IS_ERR(dev)) { sdio_uart_port_remove(port); ret = PTR_ERR(dev); } }
return ret;}
static void sdio_uart_remove(struct sdio_func *func){ struct sdio_uart_port *port = sdio_get_drvdata(func);
tty_unregister_device(sdio_uart_tty_driver, port->index); sdio_uart_port_remove(port);}
static const struct sdio_device_id sdio_uart_ids[] = { { SDIO_DEVICE_CLASS(SDIO_CLASS_UART) }, { SDIO_DEVICE_CLASS(SDIO_CLASS_GPS) }, { /* end: all zeroes */ },};
MODULE_DEVICE_TABLE(sdio, sdio_uart_ids);
static struct sdio_driver sdio_uart_driver = { .probe = sdio_uart_probe, .remove = sdio_uart_remove, .name = "sdio_uart", .id_table = sdio_uart_ids,};
static int __init sdio_uart_init(void){ int ret; struct tty_driver *tty_drv;
sdio_uart_tty_driver = tty_drv = tty_alloc_driver(UART_NR, TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV); if (IS_ERR(tty_drv)) return PTR_ERR(tty_drv);
tty_drv->driver_name = "sdio_uart"; tty_drv->name = "ttySDIO"; tty_drv->major = 0; /* dynamically allocated */ tty_drv->minor_start = 0; tty_drv->type = TTY_DRIVER_TYPE_SERIAL; tty_drv->subtype = SERIAL_TYPE_NORMAL; tty_drv->init_termios = tty_std_termios; tty_drv->init_termios.c_cflag = B4800 | CS8 | CREAD | HUPCL | CLOCAL; tty_drv->init_termios.c_ispeed = 4800; tty_drv->init_termios.c_ospeed = 4800; tty_set_operations(tty_drv, &sdio_uart_ops);
ret = tty_register_driver(tty_drv); if (ret) goto err1;
ret = sdio_register_driver(&sdio_uart_driver); if (ret) goto err2;
return 0;
err2: tty_unregister_driver(tty_drv);err1: tty_driver_kref_put(tty_drv); return ret;}
static void __exit sdio_uart_exit(void){ sdio_unregister_driver(&sdio_uart_driver); tty_unregister_driver(sdio_uart_tty_driver); tty_driver_kref_put(sdio_uart_tty_driver);}
module_init(sdio_uart_init);module_exit(sdio_uart_exit);
MODULE_AUTHOR("Nicolas Pitre");MODULE_DESCRIPTION("SDIO UART/GPS driver");MODULE_LICENSE("GPL");