Merge bk://bk.arm.linux.org.uk/linux-2.6-serial

into ppc970.osdl.org:/home/torvalds/v2.5/linux

drivers/serial/Kconfig

@@ -324,6 +324,29 @@ config SERIAL_UART00_CONSOLE
 	  your boot loader (lilo or loadlin) about how to pass options to the
 	  kernel at boot time.)
 
+config SERIAL_PXA
+	bool "PXA serial port support"
+	depends on ARM && ARCH_PXA
+	select SERIAL_CORE
+	help
+	  If you have a machine based on an Intel XScale PXA2xx CPU you
+	  can enable its onboard serial ports by enabling this option.
+
+config SERIAL_PXA_CONSOLE
+	bool "Console on PXA serial port"
+	depends on SERIAL_PXA
+	select SERIAL_CORE_CONSOLE
+	help
+	  If you have enabled the serial port on the Intel XScale PXA
+	  CPU you can make it the console by answering Y to this option.
+
+	  Even if you say Y here, the currently visible virtual console
+	  (/dev/tty0) will still be used as the system console by default, but
+	  you can alter that using a kernel command line option such as
+	  "console=ttySA0". (Try "man bootparam" or see the documentation of
+	  your boot loader (lilo or loadlin) about how to pass options to the
+	  kernel at boot time.)
+
 config SERIAL_SA1100
 	bool "SA1100 serial port support"
 	depends on ARM && ARCH_SA1100

drivers/serial/Makefile

@@ -19,6 +19,7 @@ obj-$(CONFIG_SERIAL_8250_ACORN) += 8250_acorn.o
 obj-$(CONFIG_SERIAL_ANAKIN) += anakin.o
 obj-$(CONFIG_SERIAL_AMBA) += amba.o
 obj-$(CONFIG_SERIAL_CLPS711X) += clps711x.o
+obj-$(CONFIG_SERIAL_PXA) += pxa.o
 obj-$(CONFIG_SERIAL_SA1100) += sa1100.o
 obj-$(CONFIG_SERIAL_UART00) += uart00.o
 obj-$(CONFIG_SERIAL_SUNCORE) += suncore.o

drivers/serial/pxa.c

+/*
+ *  linux/drivers/serial/pxa.c
+ *
+ *  Based on drivers/serial/8250.c by Russell King.
+ *
+ *  Author:	Nicolas Pitre
+ *  Created:	Feb 20, 2003
+ *  Copyright:	(C) 2003 Monta Vista Software, Inc.
+ *
+ * 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.
+ *
+ * Note 1: This driver is made separate from the already too overloaded
+ * 8250.c because it needs some kirks of its own and that'll make it
+ * easier to add DMA support.
+ *
+ * Note 2: I'm too sick of device allocation policies for serial ports.
+ * If someone else wants to request an "official" allocation of major/minor
+ * for this driver please be my guest.  And don't forget that new hardware
+ * to come from Intel might have more than 3 or 4 of those UARTs.  Let's
+ * hope for a better port registration and dynamic device allocation scheme
+ * with the serial core maintainer satisfaction to appear soon.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/tty.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/serial_reg.h>
+#include <linux/circ_buf.h>
+#include <linux/serial.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+
+#include <asm/io.h>
+#include <asm/hardware.h>
+#include <asm/irq.h>
+
+#if defined(CONFIG_SERIAL_PXA_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/serial_core.h>
+
+
+struct uart_pxa_port {
+	struct uart_port        port;
+	unsigned char           ier;
+	unsigned char           lcr;
+	unsigned char           mcr;
+	unsigned int            lsr_break_flag;
+	unsigned int		cken;
+	char			*name;
+};
+
+static inline unsigned int serial_in(struct uart_pxa_port *up, int offset)
+{
+	offset <<= 2;
+	return readl(up->port.membase + offset);
+}
+
+static inline void serial_out(struct uart_pxa_port *up, int offset, int value)
+{
+	offset <<= 2;
+	writel(value, up->port.membase + offset);
+}
+
+static void serial_pxa_enable_ms(struct uart_port *port)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+
+	up->ier |= UART_IER_MSI;
+	serial_out(up, UART_IER, up->ier);
+}
+
+static void serial_pxa_stop_tx(struct uart_port *port, unsigned int tty_stop)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+
+	if (up->ier & UART_IER_THRI) {
+		up->ier &= ~UART_IER_THRI;
+		serial_out(up, UART_IER, up->ier);
+	}
+}
+
+static void serial_pxa_stop_rx(struct uart_port *port)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+
+	up->ier &= ~UART_IER_RLSI;
+	up->port.read_status_mask &= ~UART_LSR_DR;
+	serial_out(up, UART_IER, up->ier);
+}
+
+static inline void
+receive_chars(struct uart_pxa_port *up, int *status, struct pt_regs *regs)
+{
+	struct tty_struct *tty = up->port.info->tty;
+	unsigned char ch;
+	int max_count = 256;
+
+	do {
+		if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
+			/*
+			 * FIXME: Deadlock can happen here if we're a
+			 * low-latency port.  We're holding the per-port
+			 * spinlock, and we call flush_to_ldisc->
+			 * n_tty_receive_buf->n_tty_receive_char->
+			 * opost->uart_put_char.
+			 */
+			tty->flip.work.func((void *)tty);
+			if (tty->flip.count >= TTY_FLIPBUF_SIZE)
+				return; // if TTY_DONT_FLIP is set
+		}
+		ch = serial_in(up, UART_RX);
+		*tty->flip.char_buf_ptr = ch;
+		*tty->flip.flag_buf_ptr = TTY_NORMAL;
+		up->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);
+				up->port.icount.brk++;
+				/*
+				 * We do the SysRQ and SAK checking
+				 * here because otherwise the break
+				 * may get masked by ignore_status_mask
+				 * or read_status_mask.
+				 */
+				if (uart_handle_break(&up->port))
+					goto ignore_char;
+			} else if (*status & UART_LSR_PE)
+				up->port.icount.parity++;
+			else if (*status & UART_LSR_FE)
+				up->port.icount.frame++;
+			if (*status & UART_LSR_OE)
+				up->port.icount.overrun++;
+
+			/*
+			 * Mask off conditions which should be ignored.
+			 */
+			*status &= up->port.read_status_mask;
+
+#ifdef CONFIG_SERIAL_PXA_CONSOLE
+			if (up->port.line == up->port.cons->index) {
+				/* Recover the break flag from console xmit */
+				*status |= up->lsr_break_flag;
+				up->lsr_break_flag = 0;
+			}
+#endif
+			if (*status & UART_LSR_BI) {
+				*tty->flip.flag_buf_ptr = TTY_BREAK;
+			} else if (*status & UART_LSR_PE)
+				*tty->flip.flag_buf_ptr = TTY_PARITY;
+			else if (*status & UART_LSR_FE)
+				*tty->flip.flag_buf_ptr = TTY_FRAME;
+		}
+		if (uart_handle_sysrq_char(&up->port, ch, regs))
+			goto ignore_char;
+		if ((*status & up->port.ignore_status_mask) == 0) {
+			tty->flip.flag_buf_ptr++;
+			tty->flip.char_buf_ptr++;
+			tty->flip.count++;
+		}
+		if ((*status & UART_LSR_OE) &&
+		    tty->flip.count < TTY_FLIPBUF_SIZE) {
+			/*
+			 * Overrun is special, since it's reported
+			 * immediately, and doesn't affect the current
+			 * character.
+			 */
+			*tty->flip.flag_buf_ptr = TTY_OVERRUN;
+			tty->flip.flag_buf_ptr++;
+			tty->flip.char_buf_ptr++;
+			tty->flip.count++;
+		}
+	ignore_char:
+		*status = serial_in(up, UART_LSR);
+	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
+	tty_flip_buffer_push(tty);
+}
+
+static void transmit_chars(struct uart_pxa_port *up)
+{
+	struct circ_buf *xmit = &up->port.info->xmit;
+	int count;
+
+	if (up->port.x_char) {
+		serial_out(up, UART_TX, up->port.x_char);
+		up->port.icount.tx++;
+		up->port.x_char = 0;
+		return;
+	}
+	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
+		serial_pxa_stop_tx(&up->port, 0);
+		return;
+	}
+
+	count = up->port.fifosize / 2;
+	do {
+		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		up->port.icount.tx++;
+		if (uart_circ_empty(xmit))
+			break;
+	} while (--count > 0);
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(&up->port);
+
+
+	if (uart_circ_empty(xmit))
+		serial_pxa_stop_tx(&up->port, 0);
+}
+
+static void serial_pxa_start_tx(struct uart_port *port, unsigned int tty_start)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+
+	if (!(up->ier & UART_IER_THRI)) {
+		up->ier |= UART_IER_THRI;
+		serial_out(up, UART_IER, up->ier);
+	}
+}
+
+static inline void check_modem_status(struct uart_pxa_port *up)
+{
+	int status;
+
+	status = serial_in(up, UART_MSR);
+
+	if ((status & UART_MSR_ANY_DELTA) == 0)
+		return;
+
+	if (status & UART_MSR_TERI)
+		up->port.icount.rng++;
+	if (status & UART_MSR_DDSR)
+		up->port.icount.dsr++;
+	if (status & UART_MSR_DDCD)
+		uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
+	if (status & UART_MSR_DCTS)
+		uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
+
+	wake_up_interruptible(&up->port.info->delta_msr_wait);
+}
+
+/*
+ * This handles the interrupt from one port.
+ */
+static inline irqreturn_t
+serial_pxa_irq(int irq, void *dev_id, struct pt_regs *regs)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)dev_id;
+	unsigned int iir, lsr;
+
+	iir = serial_in(up, UART_IIR);
+	if (iir & UART_IIR_NO_INT)
+		return IRQ_NONE;
+	lsr = serial_in(up, UART_LSR);
+	if (lsr & UART_LSR_DR)
+		receive_chars(up, &lsr, regs);
+	check_modem_status(up);
+	if (lsr & UART_LSR_THRE)
+		transmit_chars(up);
+	return IRQ_HANDLED;
+}
+
+static unsigned int serial_pxa_tx_empty(struct uart_port *port)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+	unsigned long flags;
+	unsigned int ret;
+
+	spin_lock_irqsave(&up->port.lock, flags);
+	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
+	spin_unlock_irqrestore(&up->port.lock, flags);
+
+	return ret;
+}
+
+static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+	unsigned long flags;
+	unsigned char status;
+	unsigned int ret;
+
+return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
+	spin_lock_irqsave(&up->port.lock, flags);
+	status = serial_in(up, UART_MSR);
+	spin_unlock_irqrestore(&up->port.lock, flags);
+
+	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 serial_pxa_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+	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;
+
+	mcr |= up->mcr;
+
+	serial_out(up, UART_MCR, mcr);
+}
+
+static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+	unsigned long flags;
+
+	spin_lock_irqsave(&up->port.lock, flags);
+	if (break_state == -1)
+		up->lcr |= UART_LCR_SBC;
+	else
+		up->lcr &= ~UART_LCR_SBC;
+	serial_out(up, UART_LCR, up->lcr);
+	spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+#if 0
+static void serial_pxa_dma_init(struct pxa_uart *up)
+{
+	up->rxdma =
+		pxa_request_dma(up->name, DMA_PRIO_LOW, pxa_receive_dma, up);
+	if (up->rxdma < 0)
+		goto out;
+	up->txdma =
+		pxa_request_dma(up->name, DMA_PRIO_LOW, pxa_transmit_dma, up);
+	if (up->txdma < 0)
+		goto err_txdma;
+	up->dmadesc = kmalloc(4 * sizeof(pxa_dma_desc), GFP_KERNEL);
+	if (!up->dmadesc)
+		goto err_alloc;
+
+	/* ... */
+err_alloc:
+	pxa_free_dma(up->txdma);
+err_rxdma:
+	pxa_free_dma(up->rxdma);
+out:
+	return;
+}
+#endif
+
+static int serial_pxa_startup(struct uart_port *port)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+	unsigned long flags;
+	int retval;
+
+	up->mcr = 0;
+
+	/*
+	 * Allocate the IRQ
+	 */
+	retval = request_irq(up->port.irq, serial_pxa_irq, 0, up->name, up);
+	if (retval)
+		return retval;
+
+	CKEN |= up->cken;
+	udelay(1);
+
+	/*
+	 * Clear the FIFO buffers and disable them.
+	 * (they will be reenabled in set_termios())
+	 */
+	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
+			UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+	serial_out(up, UART_FCR, 0);
+
+	/*
+	 * Clear the interrupt registers.
+	 */
+	(void) serial_in(up, UART_LSR);
+	(void) serial_in(up, UART_RX);
+	(void) serial_in(up, UART_IIR);
+	(void) serial_in(up, UART_MSR);
+
+	/*
+	 * Now, initialize the UART
+	 */
+	serial_out(up, UART_LCR, UART_LCR_WLEN8);
+
+	spin_lock_irqsave(&up->port.lock, flags);
+	up->port.mctrl |= TIOCM_OUT2;
+	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
+	spin_unlock_irqrestore(&up->port.lock, flags);
+
+	/*
+	 * Finally, enable interrupts.  Note: Modem status interrupts
+	 * are set via set_termios(), which will be occuring imminently
+	 * anyway, so we don't enable them here.
+	 */
+	up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
+	serial_out(up, UART_IER, up->ier);
+
+	/*
+	 * And clear the interrupt registers again for luck.
+	 */
+	(void) serial_in(up, UART_LSR);
+	(void) serial_in(up, UART_RX);
+	(void) serial_in(up, UART_IIR);
+	(void) serial_in(up, UART_MSR);
+
+	return 0;
+}
+
+static void serial_pxa_shutdown(struct uart_port *port)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+	unsigned long flags;
+
+	free_irq(up->port.irq, up);
+
+	/*
+	 * Disable interrupts from this port
+	 */
+	up->ier = 0;
+	serial_out(up, UART_IER, 0);
+
+	spin_lock_irqsave(&up->port.lock, flags);
+	up->port.mctrl &= ~TIOCM_OUT2;
+	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
+	spin_unlock_irqrestore(&up->port.lock, flags);
+
+	/*
+	 * Disable break condition and FIFOs
+	 */
+	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
+	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
+				  UART_FCR_CLEAR_RCVR |
+				  UART_FCR_CLEAR_XMIT);
+	serial_out(up, UART_FCR, 0);
+
+	CKEN &= ~up->cken;
+}
+
+static void
+serial_pxa_set_termios(struct uart_port *port, struct termios *termios,
+		       struct termios *old)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+	unsigned char cval, fcr = 0;
+	unsigned long flags;
+	unsigned int baud, quot;
+
+	switch (termios->c_cflag & CSIZE) {
+	case CS5:
+		cval = 0x00;
+		break;
+	case CS6:
+		cval = 0x01;
+		break;
+	case CS7:
+		cval = 0x02;
+		break;
+	default:
+	case CS8:
+		cval = 0x03;
+		break;
+	}
+
+	if (termios->c_cflag & CSTOPB)
+		cval |= 0x04;
+	if (termios->c_cflag & PARENB)
+		cval |= UART_LCR_PARITY;
+	if (!(termios->c_cflag & PARODD))
+		cval |= UART_LCR_EPAR;
+
+	/*
+	 * Ask the core to calculate the divisor for us.
+	 */
+	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
+	quot = uart_get_divisor(port, baud);
+
+	if ((up->port.uartclk / quot) < (2400 * 16))
+		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
+	else
+		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
+
+	/*
+	 * Ok, we're now changing the port state.  Do it with
+	 * interrupts disabled.
+	 */
+	spin_lock_irqsave(&up->port.lock, flags);
+
+	/*
+	 * Ensure the port will be enabled.
+	 * This is required especially for serial console.
+	 */
+	up->ier |= IER_UUE;
+
+	/*
+	 * Update the per-port timeout.
+	 */
+	uart_update_timeout(port, termios->c_cflag, quot);
+
+	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
+	if (termios->c_iflag & INPCK)
+		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
+	if (termios->c_iflag & (BRKINT | PARMRK))
+		up->port.read_status_mask |= UART_LSR_BI;
+
+	/*
+	 * Characters to ignore
+	 */
+	up->port.ignore_status_mask = 0;
+	if (termios->c_iflag & IGNPAR)
+		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
+	if (termios->c_iflag & IGNBRK) {
+		up->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)
+			up->port.ignore_status_mask |= UART_LSR_OE;
+	}
+
+	/*
+	 * ignore all characters if CREAD is not set
+	 */
+	if ((termios->c_cflag & CREAD) == 0)
+		up->port.ignore_status_mask |= UART_LSR_DR;
+
+	/*
+	 * CTS flow control flag and modem status interrupts
+	 */
+	up->ier &= ~UART_IER_MSI;
+	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
+		up->ier |= UART_IER_MSI;
+
+	serial_out(up, UART_IER, up->ier);
+
+	serial_out(up, UART_LCR, cval | UART_LCR_DLAB);/* set DLAB */
+	serial_out(up, UART_DLL, quot & 0xff);		/* LS of divisor */
+	serial_out(up, UART_DLM, quot >> 8);		/* MS of divisor */
+	serial_out(up, UART_LCR, cval);		/* reset DLAB */
+	up->lcr = cval;					/* Save LCR */
+	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
+	serial_out(up, UART_FCR, fcr);
+	spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static void
+serial_pxa_pm(struct uart_port *port, unsigned int state,
+	      unsigned int oldstate)
+{
+	if (state) {
+		/* sleep */
+	} else {
+		/* wake */
+	}
+}
+
+static void serial_pxa_release_port(struct uart_port *port)
+{
+}
+
+static int serial_pxa_request_port(struct uart_port *port)
+{
+	return 0;
+}
+
+static void serial_pxa_config_port(struct uart_port *port, int flags)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+	up->port.type = PORT_PXA;
+}
+
+static int
+serial_pxa_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+	/* we don't want the core code to modify any port params */
+	return -EINVAL;
+}
+
+static const char *
+serial_pxa_type(struct uart_port *port)
+{
+	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
+	return up->name;
+}
+
+#ifdef CONFIG_SERIAL_PXA_CONSOLE
+
+extern struct uart_pxa_port serial_pxa_ports[];
+extern struct uart_driver serial_pxa_reg;
+
+#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
+
+/*
+ *	Wait for transmitter & holding register to empty
+ */
+static inline void wait_for_xmitr(struct uart_pxa_port *up)
+{
+	unsigned int status, tmout = 10000;
+
+	/* Wait up to 10ms for the character(s) to be sent. */
+	do {
+		status = serial_in(up, UART_LSR);
+
+		if (status & UART_LSR_BI)
+			up->lsr_break_flag = UART_LSR_BI;
+
+		if (--tmout == 0)
+			break;
+		udelay(1);
+	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
+
+	/* Wait up to 1s for flow control if necessary */
+	if (up->port.flags & UPF_CONS_FLOW) {
+		tmout = 1000000;
+		while (--tmout &&
+		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
+			udelay(1);
+	}
+}
+
+/*
+ * Print a string to the serial port trying not to disturb
+ * any possible real use of the port...
+ *
+ *	The console_lock must be held when we get here.
+ */
+static void
+serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
+{
+	struct uart_pxa_port *up = &serial_pxa_ports[co->index];
+	unsigned int ier;
+	int i;
+
+	/*
+	 *	First save the UER then disable the interrupts
+	 */
+	ier = serial_in(up, UART_IER);
+	serial_out(up, UART_IER, UART_IER_UUE);
+
+	/*
+	 *	Now, do each character
+	 */
+	for (i = 0; i < count; i++, s++) {
+		wait_for_xmitr(up);
+
+		/*
+		 *	Send the character out.
+		 *	If a LF, also do CR...
+		 */
+		serial_out(up, UART_TX, *s);
+		if (*s == 10) {
+			wait_for_xmitr(up);
+			serial_out(up, UART_TX, 13);
+		}
+	}
+
+	/*
+	 *	Finally, wait for transmitter to become empty
+	 *	and restore the IER
+	 */
+	wait_for_xmitr(up);
+	serial_out(up, UART_IER, ier);
+}
+
+static int __init
+serial_pxa_console_setup(struct console *co, char *options)
+{
+	struct uart_pxa_port *up;
+	int baud = 9600;
+	int bits = 8;
+	int parity = 'n';
+	int flow = 'n';
+
+	if (co->index == -1 || co->index >= serial_pxa_reg.nr)
+		co->index = 0;
+       	up = &serial_pxa_ports[co->index];
+
+	if (options)
+		uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+	return uart_set_options(&up->port, co, baud, parity, bits, flow);
+}
+
+static struct console serial_pxa_console = {
+	.name		= "ttyS",
+	.write		= serial_pxa_console_write,
+	.device		= uart_console_device,
+	.setup		= serial_pxa_console_setup,
+	.flags		= CON_PRINTBUFFER,
+	.index		= -1,
+	.data		= &serial_pxa_reg,
+};
+
+static int __init
+serial_pxa_console_init(void)
+{
+	register_console(&serial_pxa_console);
+	return 0;
+}
+
+console_initcall(serial_pxa_console_init);
+
+#define PXA_CONSOLE	&serial_pxa_console
+#else
+#define PXA_CONSOLE	NULL
+#endif
+
+struct uart_ops serial_pxa_pops = {
+	.tx_empty	= serial_pxa_tx_empty,
+	.set_mctrl	= serial_pxa_set_mctrl,
+	.get_mctrl	= serial_pxa_get_mctrl,
+	.stop_tx	= serial_pxa_stop_tx,
+	.start_tx	= serial_pxa_start_tx,
+	.stop_rx	= serial_pxa_stop_rx,
+	.enable_ms	= serial_pxa_enable_ms,
+	.break_ctl	= serial_pxa_break_ctl,
+	.startup	= serial_pxa_startup,
+	.shutdown	= serial_pxa_shutdown,
+	.set_termios	= serial_pxa_set_termios,
+	.pm		= serial_pxa_pm,
+	.type		= serial_pxa_type,
+	.release_port	= serial_pxa_release_port,
+	.request_port	= serial_pxa_request_port,
+	.config_port	= serial_pxa_config_port,
+	.verify_port	= serial_pxa_verify_port,
+};
+
+static struct uart_pxa_port serial_pxa_ports[] = {
+     {	/* FFUART */
+	.name	= "FFUART",
+	.cken	= CKEN6_FFUART,
+	.port	= {
+		.type		= PORT_PXA,
+		.iotype		= SERIAL_IO_MEM,
+		.membase	= (void *)&FFUART,
+		.mapbase	= __PREG(FFUART),
+		.irq		= IRQ_FFUART,
+		.uartclk	= 921600 * 16,
+		.fifosize	= 64,
+		.flags		= ASYNC_SKIP_TEST,
+		.ops		= &serial_pxa_pops,
+		.line		= 0,
+	},
+  }, {	/* BTUART */
+	.name	= "BTUART",
+	.cken	= CKEN7_BTUART,
+	.port	= {
+		.type		= PORT_PXA,
+		.iotype		= SERIAL_IO_MEM,
+		.membase	= (void *)&BTUART,
+		.mapbase	= __PREG(BTUART),
+		.irq		= IRQ_BTUART,
+		.uartclk	= 921600 * 16,
+		.fifosize	= 64,
+		.flags		= ASYNC_SKIP_TEST,
+		.ops		= &serial_pxa_pops,
+		.line		= 1,
+	},
+  }, {	/* STUART */
+	.name	= "STUART",
+	.cken	= CKEN5_STUART,
+	.port	= {
+		.type		= PORT_PXA,
+		.iotype		= SERIAL_IO_MEM,
+		.membase	= (void *)&STUART,
+		.mapbase	= __PREG(STUART),
+		.irq		= IRQ_STUART,
+		.uartclk	= 921600 * 16,
+		.fifosize	= 64,
+		.flags		= ASYNC_SKIP_TEST,
+		.ops		= &serial_pxa_pops,
+		.line		= 2,
+	},
+  }
+};
+
+static struct uart_driver serial_pxa_reg = {
+	.owner		= THIS_MODULE,
+	.driver_name	= "PXA serial",
+	.devfs_name	= "tts/",
+	.dev_name	= "ttyS",
+	.major		= TTY_MAJOR,
+	.minor		= 64,
+	.nr		= ARRAY_SIZE(serial_pxa_ports),
+	.cons		= PXA_CONSOLE,
+};
+
+static int __init serial_pxa_init(void)
+{
+	int i, ret;
+
+	ret = uart_register_driver(&serial_pxa_reg);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < ARRAY_SIZE(serial_pxa_ports); i++)
+		uart_add_one_port(&serial_pxa_reg, &serial_pxa_ports[i].port);
+
+	return 0;
+}
+
+static void __exit serial_pxa_exit(void)
+{
+	uart_unregister_driver(&serial_pxa_reg);
+}
+
+module_init(serial_pxa_init);
+module_exit(serial_pxa_exit);
+
+MODULE_LICENSE("GPL");
+

include/linux/serial_core.h

@@ -46,6 +46,7 @@
  * separate so any additions to the old serial.c that occur before
  * we are merged can be easily merged here.
  */
+#define PORT_PXA	31
 #define PORT_AMBA	32
 #define PORT_CLPS711X	33
 #define PORT_SA1100	34

include/linux/serial_reg.h

@@ -140,6 +140,21 @@
 #define UART_MSR_DCTS	0x01	/* Delta CTS */
 #define UART_MSR_ANY_DELTA 0x0F	/* Any of the delta bits! */
 
+/*
+ * The Intel PXA2xx chip defines those bits
+ */
+#define UART_IER_DMAE	0x80	/* DMA Requests Enable */
+#define UART_IER_UUE	0x40	/* UART Unit Enable */
+#define UART_IER_NRZE	0x20	/* NRZ coding Enable */
+#define UART_IER_RTOIE	0x10	/* Receiver Time Out Interrupt Enable */
+
+#define UART_IIR_TOD	0x08	/* Character Timeout Indication Detected */
+
+#define UART_FCR_PXAR1	0x00	/* receive FIFO treshold = 1 */
+#define UART_FCR_PXAR8	0x40	/* receive FIFO treshold = 8 */
+#define UART_FCR_PXAR16	0x80	/* receive FIFO treshold = 16 */
+#define UART_FCR_PXAR32	0xc0	/* receive FIFO treshold = 32 */
+
 /*
  * These are the definitions for the Extended Features Register
  * (StarTech 16C660 only, when DLAB=1)