Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-22 02:52:56 +00:00
Code Issues Packages Projects Releases Wiki Activity
1d6ba284df
linux/drivers/tty/serial/st-asc.c
Maxime COQUELIN 1d6ba284df serial: st-asc: Fix overflow in baudrate calculation 
In the current calculation, if the required baud rate is above 262143,
we get an overflow.

This patch uses a 64bits variable to do the maths.
Also, we remove the '+1' to avoid a divide by zero if the input clock
rate is something unexpected.
Indeed, if the input clock rate is zero, it is preferable to be notified,
since the UART won't work anyway.

Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-27 11:05:08 -07:00

927 lines
22 KiB
C
Raw Blame History

/*
* st-asc.c: ST Asynchronous serial controller (ASC) driver
*
* Copyright (C) 2003-2013 STMicroelectronics (R&D) Limited
*
* 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.
*
*/
#if defined(CONFIG_SERIAL_ST_ASC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/module.h>
#include <linux/serial.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/serial_core.h>
#include <linux/clk.h>
#define DRIVER_NAME "st-asc"
#define ASC_SERIAL_NAME "ttyAS"
#define ASC_FIFO_SIZE 16
#define ASC_MAX_PORTS 8
struct asc_port {
struct uart_port port;
struct clk *clk;
unsigned int hw_flow_control:1;
unsigned int force_m1:1;
};
static struct asc_port asc_ports[ASC_MAX_PORTS];
static struct uart_driver asc_uart_driver;
/*---- UART Register definitions ------------------------------*/
/* Register offsets */
#define ASC_BAUDRATE 0x00
#define ASC_TXBUF 0x04
#define ASC_RXBUF 0x08
#define ASC_CTL 0x0C
#define ASC_INTEN 0x10
#define ASC_STA 0x14
#define ASC_GUARDTIME 0x18
#define ASC_TIMEOUT 0x1C
#define ASC_TXRESET 0x20
#define ASC_RXRESET 0x24
#define ASC_RETRIES 0x28
/* ASC_RXBUF */
#define ASC_RXBUF_PE 0x100
#define ASC_RXBUF_FE 0x200
/**
* Some of status comes from higher bits of the character and some come from
* the status register. Combining both of them in to single status using dummy
* bits.
*/
#define ASC_RXBUF_DUMMY_RX 0x10000
#define ASC_RXBUF_DUMMY_BE 0x20000
#define ASC_RXBUF_DUMMY_OE 0x40000
/* ASC_CTL */
#define ASC_CTL_MODE_MSK 0x0007
#define ASC_CTL_MODE_8BIT 0x0001
#define ASC_CTL_MODE_7BIT_PAR 0x0003
#define ASC_CTL_MODE_9BIT 0x0004
#define ASC_CTL_MODE_8BIT_WKUP 0x0005
#define ASC_CTL_MODE_8BIT_PAR 0x0007
#define ASC_CTL_STOP_MSK 0x0018
#define ASC_CTL_STOP_HALFBIT 0x0000
#define ASC_CTL_STOP_1BIT 0x0008
#define ASC_CTL_STOP_1_HALFBIT 0x0010
#define ASC_CTL_STOP_2BIT 0x0018
#define ASC_CTL_PARITYODD 0x0020
#define ASC_CTL_LOOPBACK 0x0040
#define ASC_CTL_RUN 0x0080
#define ASC_CTL_RXENABLE 0x0100
#define ASC_CTL_SCENABLE 0x0200
#define ASC_CTL_FIFOENABLE 0x0400
#define ASC_CTL_CTSENABLE 0x0800
#define ASC_CTL_BAUDMODE 0x1000
/* ASC_GUARDTIME */
#define ASC_GUARDTIME_MSK 0x00FF
/* ASC_INTEN */
#define ASC_INTEN_RBE 0x0001
#define ASC_INTEN_TE 0x0002
#define ASC_INTEN_THE 0x0004
#define ASC_INTEN_PE 0x0008
#define ASC_INTEN_FE 0x0010
#define ASC_INTEN_OE 0x0020
#define ASC_INTEN_TNE 0x0040
#define ASC_INTEN_TOI 0x0080
#define ASC_INTEN_RHF 0x0100
/* ASC_RETRIES */
#define ASC_RETRIES_MSK 0x00FF
/* ASC_RXBUF */
#define ASC_RXBUF_MSK 0x03FF
/* ASC_STA */
#define ASC_STA_RBF 0x0001
#define ASC_STA_TE 0x0002
#define ASC_STA_THE 0x0004
#define ASC_STA_PE 0x0008
#define ASC_STA_FE 0x0010
#define ASC_STA_OE 0x0020
#define ASC_STA_TNE 0x0040
#define ASC_STA_TOI 0x0080
#define ASC_STA_RHF 0x0100
#define ASC_STA_TF 0x0200
#define ASC_STA_NKD 0x0400
/* ASC_TIMEOUT */
#define ASC_TIMEOUT_MSK 0x00FF
/* ASC_TXBUF */
#define ASC_TXBUF_MSK 0x01FF
/*---- Inline function definitions ---------------------------*/
static inline struct asc_port *to_asc_port(struct uart_port *port)
{
return container_of(port, struct asc_port, port);
}
static inline u32 asc_in(struct uart_port *port, u32 offset)
{
return readl(port->membase + offset);
}
static inline void asc_out(struct uart_port *port, u32 offset, u32 value)
{
writel(value, port->membase + offset);
}
/*
* Some simple utility functions to enable and disable interrupts.
* Note that these need to be called with interrupts disabled.
*/
static inline void asc_disable_tx_interrupts(struct uart_port *port)
{
u32 intenable = asc_in(port, ASC_INTEN) & ~ASC_INTEN_THE;
asc_out(port, ASC_INTEN, intenable);
(void)asc_in(port, ASC_INTEN); /* Defeat bus write posting */
}
static inline void asc_enable_tx_interrupts(struct uart_port *port)
{
u32 intenable = asc_in(port, ASC_INTEN) | ASC_INTEN_THE;
asc_out(port, ASC_INTEN, intenable);
}
static inline void asc_disable_rx_interrupts(struct uart_port *port)
{
u32 intenable = asc_in(port, ASC_INTEN) & ~ASC_INTEN_RBE;
asc_out(port, ASC_INTEN, intenable);
(void)asc_in(port, ASC_INTEN); /* Defeat bus write posting */
}
static inline void asc_enable_rx_interrupts(struct uart_port *port)
{
u32 intenable = asc_in(port, ASC_INTEN) | ASC_INTEN_RBE;
asc_out(port, ASC_INTEN, intenable);
}
static inline u32 asc_txfifo_is_empty(struct uart_port *port)
{
return asc_in(port, ASC_STA) & ASC_STA_TE;
}
static inline u32 asc_txfifo_is_half_empty(struct uart_port *port)
{
return asc_in(port, ASC_STA) & ASC_STA_THE;
}
static inline const char *asc_port_name(struct uart_port *port)
{
return to_platform_device(port->dev)->name;
}
/*----------------------------------------------------------------------*/
/*
* This section contains code to support the use of the ASC as a
* generic serial port.
*/
static inline unsigned asc_hw_txroom(struct uart_port *port)
{
u32 status = asc_in(port, ASC_STA);
if (status & ASC_STA_THE)
return port->fifosize / 2;
else if (!(status & ASC_STA_TF))
return 1;
return 0;
}
/*
* Start transmitting chars.
* This is called from both interrupt and task level.
* Either way interrupts are disabled.
*/
static void asc_transmit_chars(struct uart_port *port)
{
struct circ_buf *xmit = &port->state->xmit;
int txroom;
unsigned char c;
txroom = asc_hw_txroom(port);
if ((txroom != 0) && port->x_char) {
c = port->x_char;
port->x_char = 0;
asc_out(port, ASC_TXBUF, c);
port->icount.tx++;
txroom = asc_hw_txroom(port);
}
if (uart_tx_stopped(port)) {
/*
* We should try and stop the hardware here, but I
* don't think the ASC has any way to do that.
*/
asc_disable_tx_interrupts(port);
return;
}
if (uart_circ_empty(xmit)) {
asc_disable_tx_interrupts(port);
return;
}
if (txroom == 0)
return;
do {
c = xmit->buf[xmit->tail];
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
asc_out(port, ASC_TXBUF, c);
port->icount.tx++;
txroom--;
} while ((txroom > 0) && (!uart_circ_empty(xmit)));
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
if (uart_circ_empty(xmit))
asc_disable_tx_interrupts(port);
}
static void asc_receive_chars(struct uart_port *port)
{
struct tty_port *tport = &port->state->port;
unsigned long status;
unsigned long c = 0;
char flag;
if (port->irq_wake)
pm_wakeup_event(tport->tty->dev, 0);
while ((status = asc_in(port, ASC_STA)) & ASC_STA_RBF) {
c = asc_in(port, ASC_RXBUF) | ASC_RXBUF_DUMMY_RX;
flag = TTY_NORMAL;
port->icount.rx++;
if ((c & (ASC_RXBUF_FE | ASC_RXBUF_PE)) ||
status & ASC_STA_OE) {
if (c & ASC_RXBUF_FE) {
if (c == (ASC_RXBUF_FE | ASC_RXBUF_DUMMY_RX)) {
port->icount.brk++;
if (uart_handle_break(port))
continue;
c |= ASC_RXBUF_DUMMY_BE;
} else {
port->icount.frame++;
}
} else if (c & ASC_RXBUF_PE) {
port->icount.parity++;
}
/*
* Reading any data from the RX FIFO clears the
* overflow error condition.
*/
if (status & ASC_STA_OE) {
port->icount.overrun++;
c |= ASC_RXBUF_DUMMY_OE;
}
c &= port->read_status_mask;
if (c & ASC_RXBUF_DUMMY_BE)
flag = TTY_BREAK;
else if (c & ASC_RXBUF_PE)
flag = TTY_PARITY;
else if (c & ASC_RXBUF_FE)
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char(port, c & 0xff))
continue;
uart_insert_char(port, c, ASC_RXBUF_DUMMY_OE, c & 0xff, flag);
}
/* Tell the rest of the system the news. New characters! */
tty_flip_buffer_push(tport);
}
static irqreturn_t asc_interrupt(int irq, void *ptr)
{
struct uart_port *port = ptr;
u32 status;
spin_lock(&port->lock);
status = asc_in(port, ASC_STA);
if (status & ASC_STA_RBF) {
/* Receive FIFO not empty */
asc_receive_chars(port);
}
if ((status & ASC_STA_THE) &&
(asc_in(port, ASC_INTEN) & ASC_INTEN_THE)) {
/* Transmitter FIFO at least half empty */
asc_transmit_chars(port);
}
spin_unlock(&port->lock);
return IRQ_HANDLED;
}
/*----------------------------------------------------------------------*/
/*
* UART Functions
*/
static unsigned int asc_tx_empty(struct uart_port *port)
{
return asc_txfifo_is_empty(port) ? TIOCSER_TEMT : 0;
}
static void asc_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
/*
* This routine is used for seting signals of: DTR, DCD, CTS/RTS
* We use ASC's hardware for CTS/RTS, so don't need any for that.
* Some boards have DTR and DCD implemented using PIO pins,
* code to do this should be hooked in here.
*/
}
static unsigned int asc_get_mctrl(struct uart_port *port)
{
/*
* This routine is used for geting signals of: DTR, DCD, DSR, RI,
* and CTS/RTS
*/
return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
}
/* There are probably characters waiting to be transmitted. */
static void asc_start_tx(struct uart_port *port)
{
struct circ_buf *xmit = &port->state->xmit;
if (!uart_circ_empty(xmit))
asc_enable_tx_interrupts(port);
}
/* Transmit stop */
static void asc_stop_tx(struct uart_port *port)
{
asc_disable_tx_interrupts(port);
}
/* Receive stop */
static void asc_stop_rx(struct uart_port *port)
{
asc_disable_rx_interrupts(port);
}
/* Handle breaks - ignored by us */
static void asc_break_ctl(struct uart_port *port, int break_state)
{
/* Nothing here yet .. */
}
/*
* Enable port for reception.
*/
static int asc_startup(struct uart_port *port)
{
if (request_irq(port->irq, asc_interrupt, IRQF_NO_SUSPEND,
asc_port_name(port), port)) {
dev_err(port->dev, "cannot allocate irq.\n");
return -ENODEV;
}
asc_transmit_chars(port);
asc_enable_rx_interrupts(port);
return 0;
}
static void asc_shutdown(struct uart_port *port)
{
asc_disable_tx_interrupts(port);
asc_disable_rx_interrupts(port);
free_irq(port->irq, port);
}
static void asc_pm(struct uart_port *port, unsigned int state,
unsigned int oldstate)
{
struct asc_port *ascport = to_asc_port(port);
unsigned long flags = 0;
u32 ctl;
switch (state) {
case UART_PM_STATE_ON:
clk_prepare_enable(ascport->clk);
break;
case UART_PM_STATE_OFF:
/*
* Disable the ASC baud rate generator, which is as close as
* we can come to turning it off. Note this is not called with
* the port spinlock held.
*/
spin_lock_irqsave(&port->lock, flags);
ctl = asc_in(port, ASC_CTL) & ~ASC_CTL_RUN;
asc_out(port, ASC_CTL, ctl);
spin_unlock_irqrestore(&port->lock, flags);
clk_disable_unprepare(ascport->clk);
break;
}
}
static void asc_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
struct asc_port *ascport = to_asc_port(port);
unsigned int baud;
u32 ctrl_val;
tcflag_t cflag;
unsigned long flags;
/* Update termios to reflect hardware capabilities */
termios->c_cflag &= ~(CMSPAR |
(ascport->hw_flow_control ? 0 : CRTSCTS));
port->uartclk = clk_get_rate(ascport->clk);
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
cflag = termios->c_cflag;
spin_lock_irqsave(&port->lock, flags);
/* read control register */
ctrl_val = asc_in(port, ASC_CTL);
/* stop serial port and reset value */
asc_out(port, ASC_CTL, (ctrl_val & ~ASC_CTL_RUN));
ctrl_val = ASC_CTL_RXENABLE | ASC_CTL_FIFOENABLE;
/* reset fifo rx & tx */
asc_out(port, ASC_TXRESET, 1);
asc_out(port, ASC_RXRESET, 1);
/* set character length */
if ((cflag & CSIZE) == CS7) {
ctrl_val |= ASC_CTL_MODE_7BIT_PAR;
} else {
ctrl_val |= (cflag & PARENB) ? ASC_CTL_MODE_8BIT_PAR :
ASC_CTL_MODE_8BIT;
}
/* set stop bit */
ctrl_val |= (cflag & CSTOPB) ? ASC_CTL_STOP_2BIT : ASC_CTL_STOP_1BIT;
/* odd parity */
if (cflag & PARODD)
ctrl_val |= ASC_CTL_PARITYODD;
/* hardware flow control */
if ((cflag & CRTSCTS))
ctrl_val |= ASC_CTL_CTSENABLE;
if ((baud < 19200) && !ascport->force_m1) {
asc_out(port, ASC_BAUDRATE, (port->uartclk / (16 * baud)));
} else {
/*
* MODE 1: recommended for high bit rates (above 19.2K)
*
* baudrate * 16 * 2^16
* ASCBaudRate = ------------------------
* inputclock
*
* To keep maths inside 64bits, we divide inputclock by 16.
*/
u64 dividend = (u64)baud * (1 << 16);
do_div(dividend, port->uartclk / 16);
asc_out(port, ASC_BAUDRATE, dividend);
ctrl_val |= ASC_CTL_BAUDMODE;
}
uart_update_timeout(port, cflag, baud);
ascport->port.read_status_mask = ASC_RXBUF_DUMMY_OE;
if (termios->c_iflag & INPCK)
ascport->port.read_status_mask |= ASC_RXBUF_FE | ASC_RXBUF_PE;
if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
ascport->port.read_status_mask |= ASC_RXBUF_DUMMY_BE;
/*
* Characters to ignore
*/
ascport->port.ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
ascport->port.ignore_status_mask |= ASC_RXBUF_FE | ASC_RXBUF_PE;
if (termios->c_iflag & IGNBRK) {
ascport->port.ignore_status_mask |= ASC_RXBUF_DUMMY_BE;
/*
* If we're ignoring parity and break indicators,
* ignore overruns too (for real raw support).
*/
if (termios->c_iflag & IGNPAR)
ascport->port.ignore_status_mask |= ASC_RXBUF_DUMMY_OE;
}
/*
* Ignore all characters if CREAD is not set.
*/
if (!(termios->c_cflag & CREAD))
ascport->port.ignore_status_mask |= ASC_RXBUF_DUMMY_RX;
/* Set the timeout */
asc_out(port, ASC_TIMEOUT, 20);
/* write final value and enable port */
asc_out(port, ASC_CTL, (ctrl_val | ASC_CTL_RUN));
spin_unlock_irqrestore(&port->lock, flags);
}
static const char *asc_type(struct uart_port *port)
{
return (port->type == PORT_ASC) ? DRIVER_NAME : NULL;
}
static void asc_release_port(struct uart_port *port)
{
}
static int asc_request_port(struct uart_port *port)
{
return 0;
}
/*
* Called when the port is opened, and UPF_BOOT_AUTOCONF flag is set
* Set type field if successful
*/
static void asc_config_port(struct uart_port *port, int flags)
{
if ((flags & UART_CONFIG_TYPE))
port->type = PORT_ASC;
}
static int
asc_verify_port(struct uart_port *port, struct serial_struct *ser)
{
/* No user changeable parameters */
return -EINVAL;
}
#ifdef CONFIG_CONSOLE_POLL
/*
* Console polling routines for writing and reading from the uart while
* in an interrupt or debug context (i.e. kgdb).
*/
static int asc_get_poll_char(struct uart_port *port)
{
if (!(asc_in(port, ASC_STA) & ASC_STA_RBF))
return NO_POLL_CHAR;
return asc_in(port, ASC_RXBUF);
}
static void asc_put_poll_char(struct uart_port *port, unsigned char c)
{
while (!asc_txfifo_is_half_empty(port))
cpu_relax();
asc_out(port, ASC_TXBUF, c);
}
#endif /* CONFIG_CONSOLE_POLL */
/*---------------------------------------------------------------------*/
static struct uart_ops asc_uart_ops = {
.tx_empty = asc_tx_empty,
.set_mctrl = asc_set_mctrl,
.get_mctrl = asc_get_mctrl,
.start_tx = asc_start_tx,
.stop_tx = asc_stop_tx,
.stop_rx = asc_stop_rx,
.break_ctl = asc_break_ctl,
.startup = asc_startup,
.shutdown = asc_shutdown,
.set_termios = asc_set_termios,
.type = asc_type,
.release_port = asc_release_port,
.request_port = asc_request_port,
.config_port = asc_config_port,
.verify_port = asc_verify_port,
.pm = asc_pm,
#ifdef CONFIG_CONSOLE_POLL
.poll_get_char = asc_get_poll_char,
.poll_put_char = asc_put_poll_char,
#endif /* CONFIG_CONSOLE_POLL */
};
static int asc_init_port(struct asc_port *ascport,
struct platform_device *pdev)
{
struct uart_port *port = &ascport->port;
struct resource *res;
port->iotype = UPIO_MEM;
port->flags = UPF_BOOT_AUTOCONF;
port->ops = &asc_uart_ops;
port->fifosize = ASC_FIFO_SIZE;
port->dev = &pdev->dev;
port->irq = platform_get_irq(pdev, 0);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
port->membase = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(port->membase))
return PTR_ERR(port->membase);
port->mapbase = res->start;
spin_lock_init(&port->lock);
ascport->clk = devm_clk_get(&pdev->dev, NULL);
if (WARN_ON(IS_ERR(ascport->clk)))
return -EINVAL;
/* ensure that clk rate is correct by enabling the clk */
clk_prepare_enable(ascport->clk);
ascport->port.uartclk = clk_get_rate(ascport->clk);
WARN_ON(ascport->port.uartclk == 0);
clk_disable_unprepare(ascport->clk);
return 0;
}
static struct asc_port *asc_of_get_asc_port(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
int id;
if (!np)
return NULL;
id = of_alias_get_id(np, ASC_SERIAL_NAME);
if (id < 0)
id = 0;
if (WARN_ON(id >= ASC_MAX_PORTS))
return NULL;
asc_ports[id].hw_flow_control = of_property_read_bool(np,
"st,hw-flow-control");
asc_ports[id].force_m1 = of_property_read_bool(np, "st,force_m1");
asc_ports[id].port.line = id;
return &asc_ports[id];
}
#ifdef CONFIG_OF
static struct of_device_id asc_match[] = {
{ .compatible = "st,asc", },
{},
};
MODULE_DEVICE_TABLE(of, asc_match);
#endif
static int asc_serial_probe(struct platform_device *pdev)
{
int ret;
struct asc_port *ascport;
ascport = asc_of_get_asc_port(pdev);
if (!ascport)
return -ENODEV;
ret = asc_init_port(ascport, pdev);
if (ret)
return ret;
ret = uart_add_one_port(&asc_uart_driver, &ascport->port);
if (ret)
return ret;
platform_set_drvdata(pdev, &ascport->port);
return 0;
}
static int asc_serial_remove(struct platform_device *pdev)
{
struct uart_port *port = platform_get_drvdata(pdev);
return uart_remove_one_port(&asc_uart_driver, port);
}
#ifdef CONFIG_PM_SLEEP
static int asc_serial_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct uart_port *port = platform_get_drvdata(pdev);
return uart_suspend_port(&asc_uart_driver, port);
}
static int asc_serial_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct uart_port *port = platform_get_drvdata(pdev);
return uart_resume_port(&asc_uart_driver, port);
}
#endif /* CONFIG_PM_SLEEP */
/*----------------------------------------------------------------------*/
#ifdef CONFIG_SERIAL_ST_ASC_CONSOLE
static void asc_console_putchar(struct uart_port *port, int ch)
{
unsigned int timeout = 1000000;
/* Wait for upto 1 second in case flow control is stopping us. */
while (--timeout && !asc_txfifo_is_half_empty(port))
udelay(1);
asc_out(port, ASC_TXBUF, ch);
}
/*
* Print a string to the serial port trying not to disturb
* any possible real use of the port...
*/
static void asc_console_write(struct console *co, const char *s, unsigned count)
{
struct uart_port *port = &asc_ports[co->index].port;
unsigned long flags;
unsigned long timeout = 1000000;
int locked = 1;
u32 intenable;
local_irq_save(flags);
if (port->sysrq)
locked = 0; /* asc_interrupt has already claimed the lock */
else if (oops_in_progress)
locked = spin_trylock(&port->lock);
else
spin_lock(&port->lock);
/*
* Disable interrupts so we don't get the IRQ line bouncing
* up and down while interrupts are disabled.
*/
intenable = asc_in(port, ASC_INTEN);
asc_out(port, ASC_INTEN, 0);
(void)asc_in(port, ASC_INTEN); /* Defeat bus write posting */
uart_console_write(port, s, count, asc_console_putchar);
while (--timeout && !asc_txfifo_is_empty(port))
udelay(1);
asc_out(port, ASC_INTEN, intenable);
if (locked)
spin_unlock(&port->lock);
local_irq_restore(flags);
}
static int asc_console_setup(struct console *co, char *options)
{
struct asc_port *ascport;
int baud = 9600;
int bits = 8;
int parity = 'n';
int flow = 'n';
if (co->index >= ASC_MAX_PORTS)
return -ENODEV;
ascport = &asc_ports[co->index];
/*
* This driver does not support early console initialization
* (use ARM early printk support instead), so we only expect
* this to be called during the uart port registration when the
* driver gets probed and the port should be mapped at that point.
*/
if (ascport->port.mapbase == 0 || ascport->port.membase == NULL)
return -ENXIO;
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
return uart_set_options(&ascport->port, co, baud, parity, bits, flow);
}
static struct console asc_console = {
.name = ASC_SERIAL_NAME,
.device = uart_console_device,
.write = asc_console_write,
.setup = asc_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &asc_uart_driver,
};
#define ASC_SERIAL_CONSOLE (&asc_console)
#else
#define ASC_SERIAL_CONSOLE NULL
#endif /* CONFIG_SERIAL_ST_ASC_CONSOLE */
static struct uart_driver asc_uart_driver = {
.owner = THIS_MODULE,
.driver_name = DRIVER_NAME,
.dev_name = ASC_SERIAL_NAME,
.major = 0,
.minor = 0,
.nr = ASC_MAX_PORTS,
.cons = ASC_SERIAL_CONSOLE,
};
static const struct dev_pm_ops asc_serial_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(asc_serial_suspend, asc_serial_resume)
};
static struct platform_driver asc_serial_driver = {
.probe = asc_serial_probe,
.remove = asc_serial_remove,
.driver = {
.name = DRIVER_NAME,
.pm = &asc_serial_pm_ops,
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(asc_match),
},
};
static int __init asc_init(void)
{
int ret;
static char banner[] __initdata =
KERN_INFO "STMicroelectronics ASC driver initialized\n";
printk(banner);
ret = uart_register_driver(&asc_uart_driver);
if (ret)
return ret;
ret = platform_driver_register(&asc_serial_driver);
if (ret)
uart_unregister_driver(&asc_uart_driver);
return ret;
}
static void __exit asc_exit(void)
{
platform_driver_unregister(&asc_serial_driver);
uart_unregister_driver(&asc_uart_driver);
}
module_init(asc_init);
module_exit(asc_exit);
MODULE_ALIAS("platform:" DRIVER_NAME);
MODULE_AUTHOR("STMicroelectronics (R&D) Limited");
MODULE_DESCRIPTION("STMicroelectronics ASC serial port driver");
MODULE_LICENSE("GPL");
Reference in New Issue View Git Blame Copy Permalink