[PATCH 1/2] serial: Add auart driver for i.MX23/28
Sascha Hauer
s.hauer at pengutronix.de
Thu Jan 13 08:14:35 EST 2011
Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
drivers/serial/Kconfig | 15 +
drivers/serial/Makefile | 1 +
drivers/serial/mxs-auart.c | 806 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 822 insertions(+), 0 deletions(-)
create mode 100644 drivers/serial/mxs-auart.c
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index ec3c214..6a2a39c 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -1657,4 +1657,19 @@ config SERIAL_PCH_UART
This driver is for PCH(Platform controller Hub) UART of Intel EG20T
which is an IOH(Input/Output Hub) for x86 embedded processor.
Enabling PCH_DMA, this PCH UART works as DMA mode.
+
+config SERIAL_MXS_AUART
+ depends on ARCH_MXS
+ tristate "MXS AUART support"
+ select SERIAL_CORE
+ help
+ This driver supports the MXS Application UART (AUART) port.
+
+config SERIAL_MXS_AUART_CONSOLE
+ bool "MXS AUART console support"
+ depends on SERIAL_MXS_AUART=y
+ select SERIAL_CORE_CONSOLE
+ help
+ Enable a MXS AUART port to be the system console.
+
endmenu
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index 8ea92e9..c855071 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -92,3 +92,4 @@ obj-$(CONFIG_SERIAL_MRST_MAX3110) += mrst_max3110.o
obj-$(CONFIG_SERIAL_MFD_HSU) += mfd.o
obj-$(CONFIG_SERIAL_IFX6X60) += ifx6x60.o
obj-$(CONFIG_SERIAL_PCH_UART) += pch_uart.o
+obj-$(CONFIG_SERIAL_MXS_AUART) += mxs-auart.o
diff --git a/drivers/serial/mxs-auart.c b/drivers/serial/mxs-auart.c
new file mode 100644
index 0000000..6529fd7
--- /dev/null
+++ b/drivers/serial/mxs-auart.c
@@ -0,0 +1,806 @@
+/*
+ * Freescale STMP37XX/STMP378X Application UART driver
+ *
+ * Author: dmitry pervushin <dimka at embeddedalley.com>
+ *
+ * Copyright 2008-2010 Freescale Semiconductor, Inc.
+ * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+
+#include <asm/cacheflush.h>
+
+#define MXS_AUART_PORTS 5
+
+#define AUART_CTRL0 0x00000000
+#define AUART_CTRL0_SET 0x00000004
+#define AUART_CTRL0_CLR 0x00000008
+#define AUART_CTRL0_TOG 0x0000000c
+#define AUART_CTRL1 0x00000010
+#define AUART_CTRL1_SET 0x00000014
+#define AUART_CTRL1_CLR 0x00000018
+#define AUART_CTRL1_TOG 0x0000001c
+#define AUART_CTRL2 0x00000020
+#define AUART_CTRL2_SET 0x00000024
+#define AUART_CTRL2_CLR 0x00000028
+#define AUART_CTRL2_TOG 0x0000002c
+#define AUART_LINECTRL 0x00000030
+#define AUART_LINECTRL_SET 0x00000034
+#define AUART_LINECTRL_CLR 0x00000038
+#define AUART_LINECTRL_TOG 0x0000003c
+#define AUART_LINECTRL2 0x00000040
+#define AUART_LINECTRL2_SET 0x00000044
+#define AUART_LINECTRL2_CLR 0x00000048
+#define AUART_LINECTRL2_TOG 0x0000004c
+#define AUART_INTR 0x00000050
+#define AUART_INTR_SET 0x00000054
+#define AUART_INTR_CLR 0x00000058
+#define AUART_INTR_TOG 0x0000005c
+#define AUART_DATA 0x00000060
+#define AUART_STAT 0x00000070
+#define AUART_DEBUG 0x00000080
+#define AUART_VERSION 0x00000090
+#define AUART_AUTOBAUD 0x000000a0
+
+#define AUART_CTRL0_SFTRST (1 << 31)
+#define AUART_CTRL0_CLKGATE (1 << 30)
+
+
+#define AUART_CTRL2_CTSEN (1 << 15)
+#define AUART_CTRL2_RTS (1 << 11)
+#define AUART_CTRL2_RXE (1 << 9)
+#define AUART_CTRL2_TXE (1 << 8)
+#define AUART_CTRL2_UARTEN (1 << 0)
+
+#define AUART_LINECTRL_BAUD_DIVINT_SHIFT 16
+#define AUART_LINECTRL_BAUD_DIVINT_MASK 0xffff0000
+#define AUART_LINECTRL_BAUD_DIVINT(v) (((v) & 0xffff) << 16)
+#define AUART_LINECTRL_BAUD_DIVFRAC_SHIFT 8
+#define AUART_LINECTRL_BAUD_DIVFRAC_MASK 0x00003f00
+#define AUART_LINECTRL_BAUD_DIVFRAC(v) (((v) & 0x3f) << 8)
+#define AUART_LINECTRL_WLEN_MASK 0x00000060
+#define AUART_LINECTRL_WLEN(v) (((v) & 0x3) << 5)
+#define AUART_LINECTRL_FEN (1 << 4)
+#define AUART_LINECTRL_STP2 (1 << 3)
+#define AUART_LINECTRL_EPS (1 << 2)
+#define AUART_LINECTRL_PEN (1 << 1)
+#define AUART_LINECTRL_BRK (1 << 0)
+
+#define AUART_INTR_RTIEN (1 << 22)
+#define AUART_INTR_TXIEN (1 << 21)
+#define AUART_INTR_RXIEN (1 << 20)
+#define AUART_INTR_CTSMIEN (1 << 17)
+#define AUART_INTR_RTIS (1 << 6)
+#define AUART_INTR_TXIS (1 << 5)
+#define AUART_INTR_RXIS (1 << 4)
+#define AUART_INTR_CTSMIS (1 << 1)
+
+#define AUART_STAT_BUSY (1 << 29)
+#define AUART_STAT_CTS (1 << 28)
+#define AUART_STAT_TXFE (1 << 27)
+#define AUART_STAT_TXFF (1 << 25)
+#define AUART_STAT_RXFE (1 << 24)
+#define AUART_STAT_OERR (1 << 19)
+#define AUART_STAT_BERR (1 << 18)
+#define AUART_STAT_PERR (1 << 17)
+#define AUART_STAT_FERR (1 << 16)
+
+#define UART_DUMMY_STAT_RX (1 << 31)
+
+static struct uart_driver auart_driver;
+
+struct mxs_auart_port {
+ struct uart_port port;
+
+ unsigned int flags;
+ unsigned int ctrl;
+
+ unsigned int irq;
+
+ struct clk *clk;
+ struct device *dev;
+};
+
+static void mxs_auart_stop_tx(struct uart_port *u);
+
+#define to_auart_port(u) container_of(u, struct mxs_auart_port, port)
+
+static inline void mxs_auart_tx_chars(struct mxs_auart_port *s)
+{
+ struct circ_buf *xmit = &s->port.state->xmit;
+
+ while (!(readl(s->port.membase + AUART_STAT) &
+ AUART_STAT_TXFF)) {
+ if (s->port.x_char) {
+ s->port.icount.tx++;
+ writel(s->port.x_char,
+ s->port.membase + AUART_DATA);
+ s->port.x_char = 0;
+ continue;
+ }
+ if (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) {
+ s->port.icount.tx++;
+ writel(xmit->buf[xmit->tail],
+ s->port.membase + AUART_DATA);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&s->port);
+ } else
+ break;
+ }
+ if (uart_circ_empty(&(s->port.state->xmit)))
+ writel(AUART_INTR_TXIEN,
+ s->port.membase + AUART_INTR_CLR);
+ else
+ writel(AUART_INTR_TXIEN,
+ s->port.membase + AUART_INTR_SET);
+
+ if (uart_tx_stopped(&s->port))
+ mxs_auart_stop_tx(&s->port);
+}
+
+static void mxs_auart_rx_char(struct mxs_auart_port *s)
+{
+ int flag;
+ u32 stat;
+ u8 c;
+
+ c = readl(s->port.membase + AUART_DATA);
+ stat = readl(s->port.membase + AUART_STAT) | UART_DUMMY_STAT_RX;
+
+ flag = TTY_NORMAL;
+ s->port.icount.rx++;
+
+ if (stat & AUART_STAT_BERR) {
+ s->port.icount.brk++;
+ if (uart_handle_break(&s->port))
+ goto out;
+ } else if (stat & AUART_STAT_PERR) {
+ s->port.icount.parity++;
+ } else if (stat & AUART_STAT_FERR) {
+ s->port.icount.frame++;
+ }
+
+ /*
+ * Mask off conditions which should be ingored.
+ */
+ stat &= s->port.read_status_mask;
+
+ if (stat & AUART_STAT_BERR) {
+ flag = TTY_BREAK;
+ } else if (stat & AUART_STAT_PERR)
+ flag = TTY_PARITY;
+ else if (stat & AUART_STAT_FERR)
+ flag = TTY_FRAME;
+
+ if (stat & AUART_STAT_OERR)
+ s->port.icount.overrun++;
+
+ if (uart_handle_sysrq_char(&s->port, c))
+ goto out;
+
+ uart_insert_char(&s->port, stat, AUART_STAT_OERR, c, flag);
+out:
+ writel(stat, s->port.membase + AUART_STAT);
+}
+
+static void mxs_auart_rx_chars(struct mxs_auart_port *s)
+{
+ struct tty_struct *tty = s->port.state->port.tty;
+ u32 stat = 0;
+
+ for (;;) {
+ stat = readl(s->port.membase + AUART_STAT);
+ if (stat & AUART_STAT_RXFE)
+ break;
+ mxs_auart_rx_char(s);
+ }
+
+ writel(stat, s->port.membase + AUART_STAT);
+ tty_flip_buffer_push(tty);
+}
+
+static int mxs_auart_request_port(struct uart_port *u)
+{
+ return 0;
+}
+
+static int mxs_auart_verify_port(struct uart_port *u,
+ struct serial_struct *ser)
+{
+ if (u->type != PORT_UNKNOWN && u->type != PORT_IMX)
+ return -EINVAL;
+ return 0;
+}
+
+static void mxs_auart_config_port(struct uart_port *u, int flags)
+{
+}
+
+static const char *mxs_auart_type(struct uart_port *u)
+{
+ struct mxs_auart_port *s = to_auart_port(u);
+
+ return dev_name(s->dev);
+}
+
+static void mxs_auart_release_port(struct uart_port *u)
+{
+}
+
+static void mxs_auart_set_mctrl(struct uart_port *u, unsigned mctrl)
+{
+ struct mxs_auart_port *s = to_auart_port(u);
+
+ u32 ctrl = readl(u->membase + AUART_CTRL2);
+
+ ctrl &= ~AUART_CTRL2_RTS;
+ if (mctrl & TIOCM_RTS)
+ ctrl |= AUART_CTRL2_RTS;
+ s->ctrl = mctrl;
+ writel(ctrl, u->membase + AUART_CTRL2);
+}
+
+static u32 mxs_auart_get_mctrl(struct uart_port *u)
+{
+ struct mxs_auart_port *s = to_auart_port(u);
+ u32 stat = readl(u->membase + AUART_STAT);
+ int ctrl2 = readl(u->membase + AUART_CTRL2);
+ u32 mctrl = s->ctrl;
+
+ mctrl &= ~TIOCM_CTS;
+ if (stat & AUART_STAT_CTS)
+ mctrl |= TIOCM_CTS;
+
+ if (ctrl2 & AUART_CTRL2_RTS)
+ mctrl |= TIOCM_RTS;
+
+ return mctrl;
+}
+
+static void mxs_auart_settermios(struct uart_port *u,
+ struct ktermios *termios,
+ struct ktermios *old)
+{
+ u32 bm, ctrl, ctrl2, div;
+ unsigned int cflag, baud;
+
+ cflag = termios->c_cflag;
+
+ ctrl = AUART_LINECTRL_FEN;
+ ctrl2 = readl(u->membase + AUART_CTRL2);
+
+ /* byte size */
+ switch (cflag & CSIZE) {
+ case CS5:
+ bm = 0;
+ break;
+ case CS6:
+ bm = 1;
+ break;
+ case CS7:
+ bm = 2;
+ break;
+ case CS8:
+ bm = 3;
+ break;
+ default:
+ return;
+ }
+
+ ctrl |= AUART_LINECTRL_WLEN(bm);
+
+ /* parity */
+ if (cflag & PARENB) {
+ ctrl |= AUART_LINECTRL_PEN;
+ if ((cflag & PARODD) == 0)
+ ctrl |= AUART_LINECTRL_EPS;
+ }
+
+ u->read_status_mask = 0;
+
+ if (termios->c_iflag & INPCK)
+ u->read_status_mask |= AUART_STAT_PERR;
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ u->read_status_mask |= AUART_STAT_BERR;
+
+ /*
+ * Characters to ignore
+ */
+ u->ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ u->ignore_status_mask |= AUART_STAT_PERR;
+ if (termios->c_iflag & IGNBRK) {
+ u->ignore_status_mask |= AUART_STAT_BERR;
+ /*
+ * If we're ignoring parity and break indicators,
+ * ignore overruns too (for real raw support).
+ */
+ if (termios->c_iflag & IGNPAR)
+ u->ignore_status_mask |= AUART_STAT_OERR;
+ }
+
+ /*
+ * ignore all characters if CREAD is not set
+ */
+ if ((termios->c_cflag & CREAD) == 0)
+ u->ignore_status_mask |= UART_DUMMY_STAT_RX;
+
+ /* figure out the stop bits requested */
+ if (cflag & CSTOPB)
+ ctrl |= AUART_LINECTRL_STP2;
+
+ /* figure out the hardware flow control settings */
+ if (cflag & CRTSCTS)
+ ctrl2 |= AUART_CTRL2_CTSEN;
+ else
+ ctrl2 &= ~AUART_CTRL2_CTSEN;
+
+ /* set baud rate */
+ baud = uart_get_baud_rate(u, termios, old, 0, u->uartclk);
+ div = u->uartclk * 32 / baud;
+ ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F);
+ ctrl |= AUART_LINECTRL_BAUD_DIVINT(div >> 6);
+
+ if ((cflag & CREAD) != 0)
+ ctrl2 |= AUART_CTRL2_RXE;
+
+ writel(ctrl, u->membase + AUART_LINECTRL);
+ writel(ctrl2, u->membase + AUART_CTRL2);
+}
+
+static irqreturn_t mxs_auart_irq_handle(int irq, void *context)
+{
+ u32 istatus, istat;
+ struct mxs_auart_port *s = context;
+ u32 stat = readl(s->port.membase + AUART_STAT);
+
+ istatus = istat = readl(s->port.membase + AUART_INTR);
+
+ if (istat & AUART_INTR_CTSMIS) {
+ uart_handle_cts_change(&s->port, stat & AUART_STAT_CTS);
+ writel(AUART_INTR_CTSMIS,
+ s->port.membase + AUART_INTR_CLR);
+ istat &= ~AUART_INTR_CTSMIS;
+ }
+
+ if (istat & (AUART_INTR_RTIS | AUART_INTR_RXIS)) {
+ mxs_auart_rx_chars(s);
+ istat &= ~(AUART_INTR_RTIS | AUART_INTR_RXIS);
+ }
+
+ if (istat & AUART_INTR_TXIS) {
+ mxs_auart_tx_chars(s);
+ istat &= ~AUART_INTR_TXIS;
+ }
+
+ writel(istatus & (AUART_INTR_RTIS
+ | AUART_INTR_TXIS
+ | AUART_INTR_RXIS
+ | AUART_INTR_CTSMIS),
+ s->port.membase + AUART_INTR_CLR);
+
+ return IRQ_HANDLED;
+}
+
+static void mxs_auart_reset(struct uart_port *u)
+{
+ int i;
+ unsigned int reg;
+
+ writel(AUART_CTRL0_SFTRST,
+ u->membase + AUART_CTRL0_CLR);
+
+ for (i = 0; i < 10000; i++) {
+ reg = readl(u->membase + AUART_CTRL0);
+ if (!(reg & AUART_CTRL0_SFTRST))
+ break;
+ udelay(3);
+ }
+}
+
+static int mxs_auart_startup(struct uart_port *u)
+{
+ struct mxs_auart_port *s = to_auart_port(u);
+
+ clk_enable(s->clk);
+
+ writel(AUART_CTRL0_CLKGATE,
+ u->membase + AUART_CTRL0_CLR);
+
+ writel(AUART_CTRL2_UARTEN,
+ s->port.membase + AUART_CTRL2_SET);
+
+ writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN,
+ s->port.membase + AUART_INTR);
+
+ writel(AUART_INTR_CTSMIEN,
+ s->port.membase + AUART_INTR_SET);
+
+ /*
+ * Enable fifo so all four bytes of a DMA word are written to
+ * output (otherwise, only the LSB is written, ie. 1 in 4 bytes)
+ */
+ writel(AUART_LINECTRL_FEN,
+ s->port.membase + AUART_LINECTRL_SET);
+
+ return 0;
+}
+
+static void mxs_auart_shutdown(struct uart_port *u)
+{
+ struct mxs_auart_port *s = to_auart_port(u);
+
+ writel(AUART_CTRL2_UARTEN,
+ s->port.membase + AUART_CTRL2_CLR);
+
+ writel(AUART_CTRL0_CLKGATE,
+ u->membase + AUART_CTRL0_SET);
+
+ writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN |
+ AUART_INTR_CTSMIEN,
+ s->port.membase + AUART_INTR_CLR);
+
+ clk_disable(s->clk);
+}
+
+static unsigned int mxs_auart_tx_empty(struct uart_port *u)
+{
+ if (readl(u->membase + AUART_STAT) & AUART_STAT_TXFE)
+ return TIOCSER_TEMT;
+ else
+ return 0;
+}
+
+static void mxs_auart_start_tx(struct uart_port *u)
+{
+ struct mxs_auart_port *s = to_auart_port(u);
+
+ /* enable transmitter */
+ writel(AUART_CTRL2_TXE, u->membase + AUART_CTRL2_SET);
+
+ mxs_auart_tx_chars(s);
+}
+
+static void mxs_auart_stop_tx(struct uart_port *u)
+{
+ writel(AUART_CTRL2_TXE, u->membase + AUART_CTRL2_CLR);
+}
+
+static void mxs_auart_stop_rx(struct uart_port *u)
+{
+ writel(AUART_CTRL2_RXE, u->membase + AUART_CTRL2_CLR);
+}
+
+static void mxs_auart_break_ctl(struct uart_port *u, int ctl)
+{
+ if (ctl)
+ writel(AUART_LINECTRL_BRK,
+ u->membase + AUART_LINECTRL_SET);
+ else
+ writel(AUART_LINECTRL_BRK,
+ u->membase + AUART_LINECTRL_CLR);
+}
+
+static void mxs_auart_enable_ms(struct uart_port *port)
+{
+ /* just empty */
+}
+
+static struct uart_ops mxs_auart_ops = {
+ .tx_empty = mxs_auart_tx_empty,
+ .start_tx = mxs_auart_start_tx,
+ .stop_tx = mxs_auart_stop_tx,
+ .stop_rx = mxs_auart_stop_rx,
+ .enable_ms = mxs_auart_enable_ms,
+ .break_ctl = mxs_auart_break_ctl,
+ .set_mctrl = mxs_auart_set_mctrl,
+ .get_mctrl = mxs_auart_get_mctrl,
+ .startup = mxs_auart_startup,
+ .shutdown = mxs_auart_shutdown,
+ .set_termios = mxs_auart_settermios,
+ .type = mxs_auart_type,
+ .release_port = mxs_auart_release_port,
+ .request_port = mxs_auart_request_port,
+ .config_port = mxs_auart_config_port,
+ .verify_port = mxs_auart_verify_port,
+};
+
+static struct mxs_auart_port *auart_port[MXS_AUART_PORTS];
+
+#ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE
+static void mxs_auart_console_putchar(struct uart_port *port, int ch)
+{
+ unsigned int status;
+
+ do {
+ status = readl(port->membase + AUART_STAT);
+ } while (status & AUART_STAT_TXFF);
+ writel(ch, port->membase + AUART_DATA);
+}
+
+static void
+auart_console_write(struct console *co, const char *str, unsigned int count)
+{
+ struct mxs_auart_port *s;
+ struct uart_port *port;
+ unsigned int status, old_ctrl0, old_ctrl2;
+
+ if (co->index > MXS_AUART_PORTS || co->index < 0)
+ return;
+
+ s = auart_port[co->index];
+ port = &s->port;
+
+ clk_enable(s->clk);
+
+ /* First save the CR then disable the interrupts */
+ old_ctrl2 = readl(port->membase + AUART_CTRL2);
+ old_ctrl0 = readl(port->membase + AUART_CTRL0);
+
+ writel(AUART_CTRL0_CLKGATE,
+ port->membase + AUART_CTRL0_CLR);
+ writel(AUART_CTRL2_UARTEN | AUART_CTRL2_TXE,
+ port->membase + AUART_CTRL2_SET);
+
+ uart_console_write(port, str, count, mxs_auart_console_putchar);
+
+ /*
+ * Finally, wait for transmitter to become empty
+ * and restore the TCR
+ */
+ do {
+ status = readl(port->membase + AUART_STAT);
+ } while (status & AUART_STAT_BUSY);
+
+ writel(old_ctrl0, port->membase + AUART_CTRL0);
+ writel(old_ctrl2, port->membase + AUART_CTRL2);
+
+ clk_disable(s->clk);
+}
+
+static void __init
+auart_console_get_options(struct uart_port *port, int *baud,
+ int *parity, int *bits)
+{
+ unsigned int lcr_h, quot;
+
+ if (!(readl(port->membase + AUART_CTRL2) & AUART_CTRL2_UARTEN))
+ return;
+
+ lcr_h = readl(port->membase + AUART_LINECTRL);
+
+ *parity = 'n';
+ if (lcr_h & AUART_LINECTRL_PEN) {
+ if (lcr_h & AUART_LINECTRL_EPS)
+ *parity = 'e';
+ else
+ *parity = 'o';
+ }
+
+ if ((lcr_h & AUART_LINECTRL_WLEN_MASK) == AUART_LINECTRL_WLEN(2))
+ *bits = 7;
+ else
+ *bits = 8;
+
+ quot = ((readl(port->membase + AUART_LINECTRL)
+ & AUART_LINECTRL_BAUD_DIVINT_MASK))
+ >> (AUART_LINECTRL_BAUD_DIVINT_SHIFT - 6);
+ quot |= ((readl(port->membase + AUART_LINECTRL)
+ & AUART_LINECTRL_BAUD_DIVFRAC_MASK))
+ >> AUART_LINECTRL_BAUD_DIVFRAC_SHIFT;
+ if (quot == 0)
+ quot = 1;
+
+ *baud = (port->uartclk << 2) / quot;
+}
+
+static int __init
+auart_console_setup(struct console *co, char *options)
+{
+ struct mxs_auart_port *s;
+ int baud = 9600;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+ int ret;
+
+ /*
+ * Check whether an invalid uart number has been specified, and
+ * if so, search for the first available port that does have
+ * console support.
+ */
+ if (co->index == -1 || co->index >= ARRAY_SIZE(auart_port))
+ co->index = 0;
+ s = auart_port[co->index];
+ if (!s)
+ return -ENODEV;
+
+ clk_enable(s->clk);
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+ else
+ auart_console_get_options(&s->port, &baud, &parity, &bits);
+
+ ret = uart_set_options(&s->port, co, baud, parity, bits, flow);
+
+ clk_disable(s->clk);
+
+ return ret;
+}
+
+static struct console auart_console = {
+ .name = "ttyAPP",
+ .write = auart_console_write,
+ .device = uart_console_device,
+ .setup = auart_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &auart_driver,
+};
+#endif
+
+static struct uart_driver auart_driver = {
+ .owner = THIS_MODULE,
+ .driver_name = "ttyAPP",
+ .dev_name = "ttyAPP",
+ .major = 0,
+ .minor = 0,
+ .nr = MXS_AUART_PORTS,
+#ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE
+ .cons = &auart_console,
+#endif
+};
+
+static int __devinit mxs_auart_probe(struct platform_device *pdev)
+{
+ struct mxs_auart_port *s;
+ u32 version;
+ int ret = 0;
+ struct resource *r;
+
+ s = kzalloc(sizeof(struct mxs_auart_port), GFP_KERNEL);
+ if (!s) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ s->clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(s->clk)) {
+ ret = PTR_ERR(s->clk);
+ goto out_free;
+ }
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!r) {
+ ret = -ENXIO;
+ goto out_free_clk;
+ }
+
+ s->port.mapbase = r->start;
+ s->port.membase = ioremap(r->start, resource_size(r));
+ s->port.ops = &mxs_auart_ops;
+ s->port.iotype = UPIO_MEM;
+ s->port.line = pdev->id < 0 ? 0 : pdev->id;
+ 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->flags = 0;
+ s->ctrl = 0;
+
+ s->irq = platform_get_irq(pdev, 0);
+ s->port.irq = s->irq;
+ ret = request_irq(s->irq, mxs_auart_irq_handle, 0, dev_name(&pdev->dev), s);
+ if (ret)
+ goto out_free_clk;
+
+ platform_set_drvdata(pdev, s);
+
+ auart_port[pdev->id] = s;
+
+ mxs_auart_reset(&s->port);
+
+ ret = uart_add_one_port(&auart_driver, &s->port);
+ if (ret)
+ goto out_free_irq;
+
+ version = readl(s->port.membase + AUART_VERSION);
+ dev_info(&pdev->dev, "Found APPUART %d.%d.%d\n",
+ (version >> 24) & 0xff,
+ (version >> 16) & 0xff, version & 0xffff);
+
+ return 0;
+
+out_free_irq:
+ auart_port[pdev->id] = NULL;
+ free_irq(s->irq, s);
+out_free_clk:
+ clk_put(s->clk);
+out_free:
+ kfree(s);
+out:
+ return ret;
+}
+
+static int __devexit mxs_auart_remove(struct platform_device *pdev)
+{
+ struct mxs_auart_port *s = platform_get_drvdata(pdev);
+
+ uart_remove_one_port(&auart_driver, &s->port);
+
+ auart_port[pdev->id] = NULL;
+
+ clk_put(s->clk);
+ free_irq(s->irq, s);
+ kfree(s);
+
+ return 0;
+}
+
+static struct platform_driver mxs_auart_driver = {
+ .probe = mxs_auart_probe,
+ .remove = __devexit_p(mxs_auart_remove),
+ .driver = {
+ .name = "mxs-auart",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init mxs_auart_init(void)
+{
+ int r;
+
+ r = uart_register_driver(&auart_driver);
+ if (r)
+ goto out;
+
+ r = platform_driver_register(&mxs_auart_driver);
+ if (r)
+ goto out_err;
+
+ return 0;
+out_err:
+ uart_unregister_driver(&auart_driver);
+out:
+ return r;
+}
+
+static void __exit mxs_auart_exit(void)
+{
+ platform_driver_unregister(&mxs_auart_driver);
+ uart_unregister_driver(&auart_driver);
+}
+
+module_init(mxs_auart_init);
+module_exit(mxs_auart_exit);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Freescale MXS application uart driver");
--
1.7.2.3
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