tty: serial: handle HAS_IOPORT dependencies

In a future patch HAS_IOPORT=n will disable inb()/outb() and friends at
compile time. We thus need to add HAS_IOPORT as dependency for those
drivers using them unconditionally. Some 8250 serial drivers support
MMIO only use, so fence only the parts requiring I/O ports and print an
error message if a device can't be supported with the current
configuration.

Co-developed-by: Arnd Bergmann <[e-mail]>
Signed-off-by: Arnd Bergmann <[e-mail]>
Acked-by: Greg Kroah-Hartman <[e-mail]>
Reviewed-by: Maciej W. Rozycki <[e-mail]>
Signed-off-by: Niklas Schnelle <[e-mail]>
Signed-off-by: Arnd Bergmann <[e-mail]>

drivers/tty/Kconfig

···
 
 config MOXA_SMARTIO
 	tristate "Moxa SmartIO support v. 2.0"
-	depends on SERIAL_NONSTANDARD && PCI
+	depends on SERIAL_NONSTANDARD && PCI && HAS_IOPORT
 	help
 	  Say Y here if you have a Moxa SmartIO multiport serial card and/or
 	  want to help develop a new version of this driver.
···
 
 config IPWIRELESS
 	tristate "IPWireless 3G UMTS PCMCIA card support"
-	depends on PCMCIA && NETDEVICES
+	depends on PCMCIA && NETDEVICES && HAS_IOPORT
 	select PPP
 	help
 	  This is a driver for 3G UMTS PCMCIA card from IPWireless company. In

drivers/tty/serial/8250/8250_early.c

···
 		return readl(port->membase + offset);
 	case UPIO_MEM32BE:
 		return ioread32be(port->membase + offset);
+#ifdef CONFIG_HAS_IOPORT
 	case UPIO_PORT:
 		return inb(port->iobase + offset);
+#endif
 	default:
 		return 0;
 	}
···
 	case UPIO_MEM32BE:
 		iowrite32be(value, port->membase + offset);
 		break;
+#ifdef CONFIG_HAS_IOPORT
 	case UPIO_PORT:
 		outb(value, port->iobase + offset);
 		break;
+#endif
 	}
 }
 

drivers/tty/serial/8250/8250_pci.c

···
 	struct resource *iobase = NULL;
 	u32 miscr, uartbar, ioport;
 
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(dev);
+
 	/* search for the base-ioport */
 	for (i = 0; i < ARRAY_SIZE(inta_addr); i++) {
 		iobase = request_region(inta_addr[i], ITE_887x_IOSIZE,
···
 	const struct pci_device_id *match;
 	bool amcc = false;
 
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(dev);
+
 	match = pci_match_id(quatech_cards, dev);
 	if (match)
 		amcc = match->driver_data;
···
 		  const struct pciserial_board *board,
 		  struct uart_8250_port *port, int idx)
 {
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(priv->dev);
+
 	/* Needed by pci_quatech calls below */
 	port->port.iobase = pci_resource_start(priv->dev, FL_GET_BASE(board->flags));
 	/* Set up the clocking */
···
 	u8 config_base;
 	u16 iobase;
 
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(pdev);
+
 	config_base = 0x40 + 0x08 * idx;
 
 	/* Get the io address from configuration space */
···
 	resource_size_t bar_data[3];
 	u8 config_base;
 	struct serial_private *priv = pci_get_drvdata(dev);
+
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(dev);
 
 	if (!(pci_resource_flags(dev, 5) & IORESOURCE_IO) ||
 			!(pci_resource_flags(dev, 4) & IORESOURCE_IO) ||
···
 			   const struct pciserial_board *board,
 			   struct uart_8250_port *port, int idx)
 {
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(priv->dev);
+
 	port->port.flags |= UPF_BUG_THRE;
 	port->port.serial_in = kt_serial_in;
 	port->port.handle_break = kt_handle_break;
···
 		    const struct pciserial_board *board,
 		    struct uart_8250_port *port, int idx)
 {
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(priv->dev);
+
 	port->port.flags |= UPF_FIXED_TYPE;
 	port->port.type = PORT_16550A;
 	return pci_default_setup(priv, board, port, idx);
···
 		const struct pciserial_board *board,
 		struct uart_8250_port *port, int idx)
 {
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(priv->dev);
+
 	port->port.flags |= UPF_FIXED_TYPE;
 	port->port.type = PORT_16550A;
 	return pci_default_setup(priv, board, port, idx);
···
 		    const struct pciserial_board *board,
 		    struct uart_8250_port *port, int idx)
 {
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(priv->dev);
+
 	port->port.flags |= UPF_FIXED_TYPE;
 	port->port.type = PORT_16850;
 	return pci_default_setup(priv, board, port, idx);
···
 	int max_port;
 	unsigned long iobase;
 
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(dev);
 
 	switch (dev->device) {
 	case 0x3853: /* 8 ports */
···
 static void pci_wch_ch38x_exit(struct pci_dev *dev)
 {
 	unsigned long iobase;
+
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT)) {
+		serial_8250_warn_need_ioport(dev);
+		return;
+	}
 
 	iobase = pci_resource_start(dev, 0);
 	outb(0x0, iobase + CH384_XINT_ENABLE_REG);
···
 	unsigned int i, num_ports = moxa_get_nports(device);
 	u8 val, init_mode = MOXA_RS232;
 
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(dev);
+
 	if (!(pci_moxa_supported_rs(dev) & MOXA_SUPP_RS232)) {
 		init_mode = MOXA_RS422;
 	}
···
 {
 	unsigned int bar = FL_GET_BASE(board->flags);
 	int offset;
+
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT))
+		return serial_8250_warn_need_ioport(priv->dev);
 
 	if (board->num_ports == 4 && idx == 3)
 		offset = 7 * board->uart_offset;

drivers/tty/serial/8250/8250_pcilib.c

···
 #include "8250.h"
 #include "8250_pcilib.h"
 
+int serial_8250_warn_need_ioport(struct pci_dev *dev)
+{
+	dev_warn(&dev->dev,
+		 "Serial port not supported because of missing I/O resource\n");
+
+	return -ENXIO;
+}
+
 int serial8250_pci_setup_port(struct pci_dev *dev, struct uart_8250_port *port,
 		   u8 bar, unsigned int offset, int regshift)
 {
···
 		port->port.mapbase = pci_resource_start(dev, bar) + offset;
 		port->port.membase = pcim_iomap_table(dev)[bar] + offset;
 		port->port.regshift = regshift;
-	} else {
+	} else if (IS_ENABLED(CONFIG_HAS_IOPORT)) {
 		port->port.iotype = UPIO_PORT;
 		port->port.iobase = pci_resource_start(dev, bar) + offset;
 		port->port.mapbase = 0;
 		port->port.membase = NULL;
 		port->port.regshift = 0;
+	} else {
+		return serial_8250_warn_need_ioport(dev);
 	}
 	return 0;
 }

drivers/tty/serial/8250/8250_pcilib.h

···
 
 int serial8250_pci_setup_port(struct pci_dev *dev, struct uart_8250_port *port, u8 bar,
 		   unsigned int offset, int regshift);
+
+int serial_8250_warn_need_ioport(struct pci_dev *dev);

drivers/tty/serial/8250/8250_port.c

···
 	serial_out(up, UART_DLM, value >> 8 & 0xff);
 }
 
+#ifdef CONFIG_HAS_IOPORT
 static unsigned int hub6_serial_in(struct uart_port *p, int offset)
 {
 	offset = offset << p->regshift;
···
 	outb(p->hub6 - 1 + offset, p->iobase);
 	outb(value, p->iobase + 1);
 }
+#endif /* CONFIG_HAS_IOPORT */
 
 static unsigned int mem_serial_in(struct uart_port *p, int offset)
 {
···
 	return ioread32be(p->membase + offset);
 }
 
+#ifdef CONFIG_HAS_IOPORT
 static unsigned int io_serial_in(struct uart_port *p, int offset)
 {
 	offset = offset << p->regshift;
···
 {
 	offset = offset << p->regshift;
 	outb(value, p->iobase + offset);
+}
+#endif
+static unsigned int no_serial_in(struct uart_port *p, int offset)
+{
+	return (unsigned int)-1;
+}
+
+static void no_serial_out(struct uart_port *p, int offset, int value)
+{
 }
 
 static int serial8250_default_handle_irq(struct uart_port *port);
···
 	up->dl_write = default_serial_dl_write;
 
 	switch (p->iotype) {
+#ifdef CONFIG_HAS_IOPORT
 	case UPIO_HUB6:
 		p->serial_in = hub6_serial_in;
 		p->serial_out = hub6_serial_out;
 		break;
+#endif
 
 	case UPIO_MEM:
 		p->serial_in = mem_serial_in;
···
 		p->serial_in = mem32be_serial_in;
 		p->serial_out = mem32be_serial_out;
 		break;
-
-	default:
+#ifdef CONFIG_HAS_IOPORT
+	case UPIO_PORT:
 		p->serial_in = io_serial_in;
 		p->serial_out = io_serial_out;
 		break;
+#endif
+	default:
+		WARN(1, "Unsupported UART type %x\n", p->iotype);
+		p->serial_in = no_serial_in;
+		p->serial_out = no_serial_out;
 	}
 	/* Remember loaded iotype */
 	up->cur_iotype = p->iotype;
···
 		 */
 		scratch = serial_in(up, UART_IER);
 		serial_out(up, UART_IER, 0);
-#ifdef __i386__
+#if defined(__i386__) && defined(CONFIG_HAS_IOPORT)
 		outb(0xff, 0x080);
 #endif
 		/*
···
 		 */
 		scratch2 = serial_in(up, UART_IER) & UART_IER_ALL_INTR;
 		serial_out(up, UART_IER, UART_IER_ALL_INTR);
-#ifdef __i386__
+#if defined(__i386__) && defined(CONFIG_HAS_IOPORT)
 		outb(0, 0x080);
 #endif
 		scratch3 = serial_in(up, UART_IER) & UART_IER_ALL_INTR;

drivers/tty/serial/8250/Kconfig

···
 
 config SERIAL_8250_FINTEK
 	bool "Support for Fintek variants"
-	depends on SERIAL_8250
+	depends on SERIAL_8250 && HAS_IOPORT
 	help
 	  Selecting this option will add support for the RS232 and RS485
 	  capabilities of the Fintek F81216A LPC to 4 UART as well similar
···
 
 config SERIAL_8250_CS
 	tristate "8250/16550 PCMCIA device support"
-	depends on PCMCIA && SERIAL_8250
+	depends on PCMCIA && SERIAL_8250 && HAS_IOPORT
 	help
 	  Say Y here to enable support for 16-bit PCMCIA serial devices,
 	  including serial port cards, modems, and the modem functions of

drivers/tty/serial/Kconfig

···
 
 config SERIAL_JSM
 	tristate "Digi International NEO and Classic PCI Support"
-	depends on PCI
+	depends on PCI && HAS_IOPORT
 	select SERIAL_CORE
 	help
 	  This is a driver for Digi International's Neo and Classic series

include/linux/serial_core.h

···
 	 * The remaining bits are serial-core specific and not modifiable by
 	 * userspace.
 	 */
+#ifdef CONFIG_HAS_IOPORT
 #define UPF_FOURPORT		((__force upf_t) ASYNC_FOURPORT       /* 1  */ )
+#else
+#define UPF_FOURPORT		0
+#endif
 #define UPF_SAK			((__force upf_t) ASYNC_SAK            /* 2  */ )
 #define UPF_SPD_HI		((__force upf_t) ASYNC_SPD_HI         /* 4  */ )
 #define UPF_SPD_VHI		((__force upf_t) ASYNC_SPD_VHI        /* 5  */ )