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linux/drivers/serial/imx.c

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/*
* linux/drivers/serial/imx.c
*
* Driver for Motorola IMX serial ports
*
* Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
*
* Author: Sascha Hauer <sascha@saschahauer.de>
* Copyright (C) 2004 Pengutronix
*
* 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
*
* [29-Mar-2005] Mike Lee
* Added hardware handshake
*/
#include <linux/config.h>
#if defined(CONFIG_SERIAL_IMX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/platform_device.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/hardware.h>
/* We've been assigned a range on the "Low-density serial ports" major */
#define SERIAL_IMX_MAJOR 204
#define MINOR_START 41
#define NR_PORTS 2
#define IMX_ISR_PASS_LIMIT 256
/*
* This is the size of our serial port register set.
*/
#define UART_PORT_SIZE 0x100
/*
* This determines how often we check the modem status signals
* for any change. They generally aren't connected to an IRQ
* so we have to poll them. We also check immediately before
* filling the TX fifo incase CTS has been dropped.
*/
#define MCTRL_TIMEOUT (250*HZ/1000)
#define DRIVER_NAME "IMX-uart"
struct imx_port {
struct uart_port port;
struct timer_list timer;
unsigned int old_status;
int txirq,rxirq,rtsirq;
};
/*
* Handle any change of modem status signal since we were last called.
*/
static void imx_mctrl_check(struct imx_port *sport)
{
unsigned int status, changed;
status = sport->port.ops->get_mctrl(&sport->port);
changed = status ^ sport->old_status;
if (changed == 0)
return;
sport->old_status = status;
if (changed & TIOCM_RI)
sport->port.icount.rng++;
if (changed & TIOCM_DSR)
sport->port.icount.dsr++;
if (changed & TIOCM_CAR)
uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
if (changed & TIOCM_CTS)
uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
wake_up_interruptible(&sport->port.info->delta_msr_wait);
}
/*
* This is our per-port timeout handler, for checking the
* modem status signals.
*/
static void imx_timeout(unsigned long data)
{
struct imx_port *sport = (struct imx_port *)data;
unsigned long flags;
if (sport->port.info) {
spin_lock_irqsave(&sport->port.lock, flags);
imx_mctrl_check(sport);
spin_unlock_irqrestore(&sport->port.lock, flags);
mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
}
}
/*
* interrupts disabled on entry
*/
static void imx_stop_tx(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
UCR1((u32)sport->port.membase) &= ~UCR1_TXMPTYEN;
}
/*
* interrupts disabled on entry
*/
static void imx_stop_rx(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
UCR2((u32)sport->port.membase) &= ~UCR2_RXEN;
}
/*
* Set the modem control timer to fire immediately.
*/
static void imx_enable_ms(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
mod_timer(&sport->timer, jiffies);
}
static inline void imx_transmit_buffer(struct imx_port *sport)
{
struct circ_buf *xmit = &sport->port.info->xmit;
do {
/* send xmit->buf[xmit->tail]
* out the port here */
URTX0((u32)sport->port.membase) = xmit->buf[xmit->tail];
xmit->tail = (xmit->tail + 1) &
(UART_XMIT_SIZE - 1);
sport->port.icount.tx++;
if (uart_circ_empty(xmit))
break;
} while (!(UTS((u32)sport->port.membase) & UTS_TXFULL));
if (uart_circ_empty(xmit))
imx_stop_tx(&sport->port);
}
/*
* interrupts disabled on entry
*/
static void imx_start_tx(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
UCR1((u32)sport->port.membase) |= UCR1_TXMPTYEN;
if(UTS((u32)sport->port.membase) & UTS_TXEMPTY)
imx_transmit_buffer(sport);
}
static irqreturn_t imx_rtsint(int irq, void *dev_id, struct pt_regs *regs)
{
struct imx_port *sport = (struct imx_port *)dev_id;
unsigned int val = USR1((u32)sport->port.membase)&USR1_RTSS;
unsigned long flags;
spin_lock_irqsave(&sport->port.lock, flags);
USR1((u32)sport->port.membase) = USR1_RTSD;
uart_handle_cts_change(&sport->port, !!val);
wake_up_interruptible(&sport->port.info->delta_msr_wait);
spin_unlock_irqrestore(&sport->port.lock, flags);
return IRQ_HANDLED;
}
static irqreturn_t imx_txint(int irq, void *dev_id, struct pt_regs *regs)
{
struct imx_port *sport = (struct imx_port *)dev_id;
struct circ_buf *xmit = &sport->port.info->xmit;
unsigned long flags;
spin_lock_irqsave(&sport->port.lock,flags);
if (sport->port.x_char)
{
/* Send next char */
URTX0((u32)sport->port.membase) = sport->port.x_char;
goto out;
}
if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
imx_stop_tx(&sport->port);
goto out;
}
imx_transmit_buffer(sport);
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&sport->port);
out:
spin_unlock_irqrestore(&sport->port.lock,flags);
return IRQ_HANDLED;
}
static irqreturn_t imx_rxint(int irq, void *dev_id, struct pt_regs *regs)
{
struct imx_port *sport = dev_id;
unsigned int rx,flg,ignored = 0;
struct tty_struct *tty = sport->port.info->tty;
unsigned long flags;
rx = URXD0((u32)sport->port.membase);
spin_lock_irqsave(&sport->port.lock,flags);
do {
flg = TTY_NORMAL;
sport->port.icount.rx++;
if( USR2((u32)sport->port.membase) & USR2_BRCD ) {
USR2((u32)sport->port.membase) |= USR2_BRCD;
if(uart_handle_break(&sport->port))
goto ignore_char;
}
if (uart_handle_sysrq_char
(&sport->port, (unsigned char)rx, regs))
goto ignore_char;
if( rx & (URXD_PRERR | URXD_OVRRUN | URXD_FRMERR) )
goto handle_error;
error_return:
tty_insert_flip_char(tty, rx, flg);
if (tty->flip.count >= TTY_FLIPBUF_SIZE)
goto out;
ignore_char:
rx = URXD0((u32)sport->port.membase);
} while(rx & URXD_CHARRDY);
out:
spin_unlock_irqrestore(&sport->port.lock,flags);
tty_flip_buffer_push(tty);
return IRQ_HANDLED;
handle_error:
if (rx & URXD_PRERR)
sport->port.icount.parity++;
else if (rx & URXD_FRMERR)
sport->port.icount.frame++;
if (rx & URXD_OVRRUN)
sport->port.icount.overrun++;
if (rx & sport->port.ignore_status_mask) {
if (++ignored > 100)
goto out;
goto ignore_char;
}
rx &= sport->port.read_status_mask;
if (rx & URXD_PRERR)
flg = TTY_PARITY;
else if (rx & URXD_FRMERR)
flg = TTY_FRAME;
if (rx & URXD_OVRRUN)
flg = TTY_OVERRUN;
#ifdef SUPPORT_SYSRQ
sport->port.sysrq = 0;
#endif
goto error_return;
}
/*
* Return TIOCSER_TEMT when transmitter is not busy.
*/
static unsigned int imx_tx_empty(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
return USR2((u32)sport->port.membase) & USR2_TXDC ? TIOCSER_TEMT : 0;
}
/*
* We have a modem side uart, so the meanings of RTS and CTS are inverted.
*/
static unsigned int imx_get_mctrl(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
unsigned int tmp = TIOCM_DSR | TIOCM_CAR;
if (USR1((u32)sport->port.membase) & USR1_RTSS)
tmp |= TIOCM_CTS;
if (UCR2((u32)sport->port.membase) & UCR2_CTS)
tmp |= TIOCM_RTS;
return tmp;
}
static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct imx_port *sport = (struct imx_port *)port;
if (mctrl & TIOCM_RTS)
UCR2((u32)sport->port.membase) |= UCR2_CTS;
else
UCR2((u32)sport->port.membase) &= ~UCR2_CTS;
}
/*
* Interrupts always disabled.
*/
static void imx_break_ctl(struct uart_port *port, int break_state)
{
struct imx_port *sport = (struct imx_port *)port;
unsigned long flags;
spin_lock_irqsave(&sport->port.lock, flags);
if ( break_state != 0 )
UCR1((u32)sport->port.membase) |= UCR1_SNDBRK;
else
UCR1((u32)sport->port.membase) &= ~UCR1_SNDBRK;
spin_unlock_irqrestore(&sport->port.lock, flags);
}
#define TXTL 2 /* reset default */
#define RXTL 1 /* reset default */
static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode)
{
unsigned int val;
unsigned int ufcr_rfdiv;
/* set receiver / transmitter trigger level.
* RFDIV is set such way to satisfy requested uartclk value
*/
val = TXTL<<10 | RXTL;
ufcr_rfdiv = (imx_get_perclk1() + sport->port.uartclk / 2) / sport->port.uartclk;
if(!ufcr_rfdiv)
ufcr_rfdiv = 1;
if(ufcr_rfdiv >= 7)
ufcr_rfdiv = 6;
else
ufcr_rfdiv = 6 - ufcr_rfdiv;
val |= UFCR_RFDIV & (ufcr_rfdiv << 7);
UFCR((u32)sport->port.membase) = val;
return 0;
}
static int imx_startup(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
int retval;
unsigned long flags;
imx_setup_ufcr(sport, 0);
/* disable the DREN bit (Data Ready interrupt enable) before
* requesting IRQs
*/
UCR4((u32)sport->port.membase) &= ~UCR4_DREN;
/*
* Allocate the IRQ
*/
retval = request_irq(sport->rxirq, imx_rxint, 0,
DRIVER_NAME, sport);
if (retval) goto error_out1;
retval = request_irq(sport->txirq, imx_txint, 0,
DRIVER_NAME, sport);
if (retval) goto error_out2;
retval = request_irq(sport->rtsirq, imx_rtsint, 0,
DRIVER_NAME, sport);
if (retval) goto error_out3;
set_irq_type(sport->rtsirq, IRQT_BOTHEDGE);
/*
* Finally, clear and enable interrupts
*/
USR1((u32)sport->port.membase) = USR1_RTSD;
UCR1((u32)sport->port.membase) |=
(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN);
UCR2((u32)sport->port.membase) |= (UCR2_RXEN | UCR2_TXEN);
/*
* Enable modem status interrupts
*/
spin_lock_irqsave(&sport->port.lock,flags);
imx_enable_ms(&sport->port);
spin_unlock_irqrestore(&sport->port.lock,flags);
return 0;
error_out3:
free_irq(sport->txirq, sport);
error_out2:
free_irq(sport->rxirq, sport);
error_out1:
return retval;
}
static void imx_shutdown(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
/*
* Stop our timer.
*/
del_timer_sync(&sport->timer);
/*
* Free the interrupts
*/
free_irq(sport->rtsirq, sport);
free_irq(sport->txirq, sport);
free_irq(sport->rxirq, sport);
/*
* Disable all interrupts, port and break condition.
*/
UCR1((u32)sport->port.membase) &=
~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN);
}
static void
imx_set_termios(struct uart_port *port, struct termios *termios,
struct termios *old)
{
struct imx_port *sport = (struct imx_port *)port;
unsigned long flags;
unsigned int ucr2, old_ucr1, old_txrxen, baud, quot;
unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
/*
* If we don't support modem control lines, don't allow
* these to be set.
*/
if (0) {
termios->c_cflag &= ~(HUPCL | CRTSCTS | CMSPAR);
termios->c_cflag |= CLOCAL;
}
/*
* We only support CS7 and CS8.
*/
while ((termios->c_cflag & CSIZE) != CS7 &&
(termios->c_cflag & CSIZE) != CS8) {
termios->c_cflag &= ~CSIZE;
termios->c_cflag |= old_csize;
old_csize = CS8;
}
if ((termios->c_cflag & CSIZE) == CS8)
ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS;
else
ucr2 = UCR2_SRST | UCR2_IRTS;
if (termios->c_cflag & CRTSCTS) {
ucr2 &= ~UCR2_IRTS;
ucr2 |= UCR2_CTSC;
}
if (termios->c_cflag & CSTOPB)
ucr2 |= UCR2_STPB;
if (termios->c_cflag & PARENB) {
ucr2 |= UCR2_PREN;
if (!(termios->c_cflag & PARODD))
ucr2 |= UCR2_PROE;
}
/*
* 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);
spin_lock_irqsave(&sport->port.lock, flags);
sport->port.read_status_mask = 0;
if (termios->c_iflag & INPCK)
sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR);
if (termios->c_iflag & (BRKINT | PARMRK))
sport->port.read_status_mask |= URXD_BRK;
/*
* Characters to ignore
*/
sport->port.ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
sport->port.ignore_status_mask |= URXD_PRERR;
if (termios->c_iflag & IGNBRK) {
sport->port.ignore_status_mask |= URXD_BRK;
/*
* If we're ignoring parity and break indicators,
* ignore overruns too (for real raw support).
*/
if (termios->c_iflag & IGNPAR)
sport->port.ignore_status_mask |= URXD_OVRRUN;
}
del_timer_sync(&sport->timer);
/*
* Update the per-port timeout.
*/
uart_update_timeout(port, termios->c_cflag, baud);
/*
* disable interrupts and drain transmitter
*/
old_ucr1 = UCR1((u32)sport->port.membase);
UCR1((u32)sport->port.membase) &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN);
while ( !(USR2((u32)sport->port.membase) & USR2_TXDC))
barrier();
/* then, disable everything */
old_txrxen = UCR2((u32)sport->port.membase) & ( UCR2_TXEN | UCR2_RXEN );
UCR2((u32)sport->port.membase) &= ~( UCR2_TXEN | UCR2_RXEN);
/* set the parity, stop bits and data size */
UCR2((u32)sport->port.membase) = ucr2;
/* set the baud rate. We assume uartclk = 16 MHz
*
* baud * 16 UBIR - 1
* --------- = --------
* uartclk UBMR - 1
*/
UBIR((u32)sport->port.membase) = (baud / 100) - 1;
UBMR((u32)sport->port.membase) = 10000 - 1;
UCR1((u32)sport->port.membase) = old_ucr1;
UCR2((u32)sport->port.membase) |= old_txrxen;
if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
imx_enable_ms(&sport->port);
spin_unlock_irqrestore(&sport->port.lock, flags);
}
static const char *imx_type(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
return sport->port.type == PORT_IMX ? "IMX" : NULL;
}
/*
* Release the memory region(s) being used by 'port'.
*/
static void imx_release_port(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
release_mem_region(sport->port.mapbase, UART_PORT_SIZE);
}
/*
* Request the memory region(s) being used by 'port'.
*/
static int imx_request_port(struct uart_port *port)
{
struct imx_port *sport = (struct imx_port *)port;
return request_mem_region(sport->port.mapbase, UART_PORT_SIZE,
"imx-uart") != NULL ? 0 : -EBUSY;
}
/*
* Configure/autoconfigure the port.
*/
static void imx_config_port(struct uart_port *port, int flags)
{
struct imx_port *sport = (struct imx_port *)port;
if (flags & UART_CONFIG_TYPE &&
imx_request_port(&sport->port) == 0)
sport->port.type = PORT_IMX;
}
/*
* Verify the new serial_struct (for TIOCSSERIAL).
* The only change we allow are to the flags and type, and
* even then only between PORT_IMX and PORT_UNKNOWN
*/
static int
imx_verify_port(struct uart_port *port, struct serial_struct *ser)
{
struct imx_port *sport = (struct imx_port *)port;
int ret = 0;
if (ser->type != PORT_UNKNOWN && ser->type != PORT_IMX)
ret = -EINVAL;
if (sport->port.irq != ser->irq)
ret = -EINVAL;
if (ser->io_type != UPIO_MEM)
ret = -EINVAL;
if (sport->port.uartclk / 16 != ser->baud_base)
ret = -EINVAL;
if ((void *)sport->port.mapbase != ser->iomem_base)
ret = -EINVAL;
if (sport->port.iobase != ser->port)
ret = -EINVAL;
if (ser->hub6 != 0)
ret = -EINVAL;
return ret;
}
static struct uart_ops imx_pops = {
.tx_empty = imx_tx_empty,
.set_mctrl = imx_set_mctrl,
.get_mctrl = imx_get_mctrl,
.stop_tx = imx_stop_tx,
.start_tx = imx_start_tx,
.stop_rx = imx_stop_rx,
.enable_ms = imx_enable_ms,
.break_ctl = imx_break_ctl,
.startup = imx_startup,
.shutdown = imx_shutdown,
.set_termios = imx_set_termios,
.type = imx_type,
.release_port = imx_release_port,
.request_port = imx_request_port,
.config_port = imx_config_port,
.verify_port = imx_verify_port,
};
static struct imx_port imx_ports[] = {
{
.txirq = UART1_MINT_TX,
.rxirq = UART1_MINT_RX,
.rtsirq = UART1_MINT_RTS,
.port = {
.type = PORT_IMX,
.iotype = SERIAL_IO_MEM,
.membase = (void *)IMX_UART1_BASE,
.mapbase = IMX_UART1_BASE, /* FIXME */
.irq = UART1_MINT_RX,
.uartclk = 16000000,
.fifosize = 8,
.flags = ASYNC_BOOT_AUTOCONF,
.ops = &imx_pops,
.line = 0,
},
}, {
.txirq = UART2_MINT_TX,
.rxirq = UART2_MINT_RX,
.rtsirq = UART2_MINT_RTS,
.port = {
.type = PORT_IMX,
.iotype = SERIAL_IO_MEM,
.membase = (void *)IMX_UART2_BASE,
.mapbase = IMX_UART2_BASE, /* FIXME */
.irq = UART2_MINT_RX,
.uartclk = 16000000,
.fifosize = 8,
.flags = ASYNC_BOOT_AUTOCONF,
.ops = &imx_pops,
.line = 1,
},
}
};
/*
* Setup the IMX serial ports.
* Note also that we support "console=ttySMXx" where "x" is either 0 or 1.
* Which serial port this ends up being depends on the machine you're
* running this kernel on. I'm not convinced that this is a good idea,
* but that's the way it traditionally works.
*
*/
static void __init imx_init_ports(void)
{
static int first = 1;
int i;
if (!first)
return;
first = 0;
for (i = 0; i < ARRAY_SIZE(imx_ports); i++) {
init_timer(&imx_ports[i].timer);
imx_ports[i].timer.function = imx_timeout;
imx_ports[i].timer.data = (unsigned long)&imx_ports[i];
}
imx_gpio_mode(PC9_PF_UART1_CTS);
imx_gpio_mode(PC10_PF_UART1_RTS);
imx_gpio_mode(PC11_PF_UART1_TXD);
imx_gpio_mode(PC12_PF_UART1_RXD);
imx_gpio_mode(PB28_PF_UART2_CTS);
imx_gpio_mode(PB29_PF_UART2_RTS);
imx_gpio_mode(PB30_PF_UART2_TXD);
imx_gpio_mode(PB31_PF_UART2_RXD);
#if 0 /* We don't need these, on the mx1 the _modem_ side of the uart
* is implemented.
*/
imx_gpio_mode(PD7_AF_UART2_DTR);
imx_gpio_mode(PD8_AF_UART2_DCD);
imx_gpio_mode(PD9_AF_UART2_RI);
imx_gpio_mode(PD10_AF_UART2_DSR);
#endif
}
#ifdef CONFIG_SERIAL_IMX_CONSOLE
/*
* Interrupts are disabled on entering
*/
static void
imx_console_write(struct console *co, const char *s, unsigned int count)
{
struct imx_port *sport = &imx_ports[co->index];
unsigned int old_ucr1, old_ucr2, i;
/*
* First, save UCR1/2 and then disable interrupts
*/
old_ucr1 = UCR1((u32)sport->port.membase);
old_ucr2 = UCR2((u32)sport->port.membase);
UCR1((u32)sport->port.membase) =
(old_ucr1 | UCR1_UARTCLKEN | UCR1_UARTEN)
& ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN);
UCR2((u32)sport->port.membase) = old_ucr2 | UCR2_TXEN;
/*
* Now, do each character
*/
for (i = 0; i < count; i++) {
while ((UTS((u32)sport->port.membase) & UTS_TXFULL))
barrier();
URTX0((u32)sport->port.membase) = s[i];
if (s[i] == '\n') {
while ((UTS((u32)sport->port.membase) & UTS_TXFULL))
barrier();
URTX0((u32)sport->port.membase) = '\r';
}
}
/*
* Finally, wait for transmitter to become empty
* and restore UCR1/2
*/
while (!(USR2((u32)sport->port.membase) & USR2_TXDC));
UCR1((u32)sport->port.membase) = old_ucr1;
UCR2((u32)sport->port.membase) = old_ucr2;
}
/*
* If the port was already initialised (eg, by a boot loader),
* try to determine the current setup.
*/
static void __init
imx_console_get_options(struct imx_port *sport, int *baud,
int *parity, int *bits)
{
if ( UCR1((u32)sport->port.membase) | UCR1_UARTEN ) {
/* ok, the port was enabled */
unsigned int ucr2, ubir,ubmr, uartclk;
unsigned int baud_raw;
unsigned int ucfr_rfdiv;
ucr2 = UCR2((u32)sport->port.membase);
*parity = 'n';
if (ucr2 & UCR2_PREN) {
if (ucr2 & UCR2_PROE)
*parity = 'o';
else
*parity = 'e';
}
if (ucr2 & UCR2_WS)
*bits = 8;
else
*bits = 7;
ubir = UBIR((u32)sport->port.membase) & 0xffff;
ubmr = UBMR((u32)sport->port.membase) & 0xffff;
ucfr_rfdiv = (UFCR((u32)sport->port.membase) & UFCR_RFDIV) >> 7;
if (ucfr_rfdiv == 6)
ucfr_rfdiv = 7;
else
ucfr_rfdiv = 6 - ucfr_rfdiv;
uartclk = imx_get_perclk1();
uartclk /= ucfr_rfdiv;
{ /*
* The next code provides exact computation of
* baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1))
* without need of float support or long long division,
* which would be required to prevent 32bit arithmetic overflow
*/
unsigned int mul = ubir + 1;
unsigned int div = 16 * (ubmr + 1);
unsigned int rem = uartclk % div;
baud_raw = (uartclk / div) * mul;
baud_raw += (rem * mul + div / 2) / div;
*baud = (baud_raw + 50) / 100 * 100;
}
if(*baud != baud_raw)
printk(KERN_INFO "Serial: Console IMX rounded baud rate from %d to %d\n",
baud_raw, *baud);
}
}
static int __init
imx_console_setup(struct console *co, char *options)
{
struct imx_port *sport;
int baud = 9600;
int bits = 8;
int parity = 'n';
int flow = 'n';
/*
* 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(imx_ports))
co->index = 0;
sport = &imx_ports[co->index];
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
imx_console_get_options(sport, &baud, &parity, &bits);
imx_setup_ufcr(sport, 0);
return uart_set_options(&sport->port, co, baud, parity, bits, flow);
}
static struct uart_driver imx_reg;
static struct console imx_console = {
.name = "ttySMX",
.write = imx_console_write,
.device = uart_console_device,
.setup = imx_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &imx_reg,
};
static int __init imx_rs_console_init(void)
{
imx_init_ports();
register_console(&imx_console);
return 0;
}
console_initcall(imx_rs_console_init);
#define IMX_CONSOLE &imx_console
#else
#define IMX_CONSOLE NULL
#endif
static struct uart_driver imx_reg = {
.owner = THIS_MODULE,
.driver_name = DRIVER_NAME,
.dev_name = "ttySMX",
.devfs_name = "ttsmx/",
.major = SERIAL_IMX_MAJOR,
.minor = MINOR_START,
.nr = ARRAY_SIZE(imx_ports),
.cons = IMX_CONSOLE,
};
static int serial_imx_suspend(struct platform_device *dev, pm_message_t state)
{
struct imx_port *sport = platform_get_drvdata(dev);
if (sport)
uart_suspend_port(&imx_reg, &sport->port);
return 0;
}
static int serial_imx_resume(struct platform_device *dev)
{
struct imx_port *sport = platform_get_drvdata(dev);
if (sport)
uart_resume_port(&imx_reg, &sport->port);
return 0;
}
static int serial_imx_probe(struct platform_device *dev)
{
imx_ports[dev->id].port.dev = &dev->dev;
uart_add_one_port(&imx_reg, &imx_ports[dev->id].port);
platform_set_drvdata(dev, &imx_ports[dev->id]);
return 0;
}
static int serial_imx_remove(struct platform_device *dev)
{
struct imx_port *sport = platform_get_drvdata(dev);
platform_set_drvdata(dev, NULL);
if (sport)
uart_remove_one_port(&imx_reg, &sport->port);
return 0;
}
static struct platform_driver serial_imx_driver = {
.probe = serial_imx_probe,
.remove = serial_imx_remove,
.suspend = serial_imx_suspend,
.resume = serial_imx_resume,
.driver = {
.name = "imx-uart",
},
};
static int __init imx_serial_init(void)
{
int ret;
printk(KERN_INFO "Serial: IMX driver\n");
imx_init_ports();
ret = uart_register_driver(&imx_reg);
if (ret)
return ret;
ret = platform_driver_register(&serial_imx_driver);
if (ret != 0)
uart_unregister_driver(&imx_reg);
return 0;
}
static void __exit imx_serial_exit(void)
{
uart_unregister_driver(&imx_reg);
platform_driver_unregister(&serial_imx_driver);
}
module_init(imx_serial_init);
module_exit(imx_serial_exit);
MODULE_AUTHOR("Sascha Hauer");
MODULE_DESCRIPTION("IMX generic serial port driver");
MODULE_LICENSE("GPL");
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