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linux/drivers/serial/amba-pl011.c
Russell King b129a8ccd5 [SERIAL] Clean up and fix tty transmission start/stoping 
The start_tx and stop_tx methods were passed a flag to indicate
whether the start/stop was from the tty start/stop callbacks, and
some drivers used this flag to decide whether to ask the UART to
immediately stop transmission (where the UART supports such a
feature.)

There are other cases when we wish this to occur - when CTS is
lowered, or if we change from soft to hard flow control and CTS
is inactive.  In these cases, this flag was false, and we would
allow the transmitter to drain before stopping.

There is really only one case where we want to let the transmitter
drain before disabling, and that's when we run out of characters
to send.

Hence, re-jig the start_tx and stop_tx methods to eliminate this
flag, and introduce new functions for the special "disable and
allow transmitter to drain" case.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-08-31 10:12:14 +01:00

860 lines
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/*
* linux/drivers/char/amba.c
*
* Driver for AMBA serial ports
*
* Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
*
* Copyright 1999 ARM Limited
* Copyright (C) 2000 Deep Blue Solutions Ltd.
*
* 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
*
* $Id: amba.c,v 1.41 2002/07/28 10:03:27 rmk Exp $
*
* This is a generic driver for ARM AMBA-type serial ports. They
* have a lot of 16550-like features, but are not register compatible.
* Note that although they do have CTS, DCD and DSR inputs, they do
* not have an RI input, nor do they have DTR or RTS outputs. If
* required, these have to be supplied via some other means (eg, GPIO)
* and hooked into this driver.
*/
#include <linux/config.h>
#if defined(CONFIG_SERIAL_AMBA_PL011_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/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/amba.h>
#include <asm/hardware/clock.h>
#include <asm/hardware/amba_serial.h>
#define UART_NR 14
#define SERIAL_AMBA_MAJOR 204
#define SERIAL_AMBA_MINOR 64
#define SERIAL_AMBA_NR UART_NR
#define AMBA_ISR_PASS_LIMIT 256
#define UART_DUMMY_RSR_RX 256
/*
* We wrap our port structure around the generic uart_port.
*/
struct uart_amba_port {
struct uart_port port;
struct clk *clk;
unsigned int im; /* interrupt mask */
unsigned int old_status;
};
static void pl011_stop_tx(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
uap->im &= ~UART011_TXIM;
writew(uap->im, uap->port.membase + UART011_IMSC);
}
static void pl011_start_tx(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
uap->im |= UART011_TXIM;
writew(uap->im, uap->port.membase + UART011_IMSC);
}
static void pl011_stop_rx(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM|
UART011_PEIM|UART011_BEIM|UART011_OEIM);
writew(uap->im, uap->port.membase + UART011_IMSC);
}
static void pl011_enable_ms(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM;
writew(uap->im, uap->port.membase + UART011_IMSC);
}
static void
#ifdef SUPPORT_SYSRQ
pl011_rx_chars(struct uart_amba_port *uap, struct pt_regs *regs)
#else
pl011_rx_chars(struct uart_amba_port *uap)
#endif
{
struct tty_struct *tty = uap->port.info->tty;
unsigned int status, ch, flag, rsr, max_count = 256;
status = readw(uap->port.membase + UART01x_FR);
while ((status & UART01x_FR_RXFE) == 0 && max_count--) {
if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
if (tty->low_latency)
tty_flip_buffer_push(tty);
/*
* If this failed then we will throw away the
* bytes but must do so to clear interrupts
*/
}
ch = readw(uap->port.membase + UART01x_DR);
flag = TTY_NORMAL;
uap->port.icount.rx++;
/*
* Note that the error handling code is
* out of the main execution path
*/
rsr = readw(uap->port.membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
if (unlikely(rsr & UART01x_RSR_ANY)) {
if (rsr & UART01x_RSR_BE) {
rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
uap->port.icount.brk++;
if (uart_handle_break(&uap->port))
goto ignore_char;
} else if (rsr & UART01x_RSR_PE)
uap->port.icount.parity++;
else if (rsr & UART01x_RSR_FE)
uap->port.icount.frame++;
if (rsr & UART01x_RSR_OE)
uap->port.icount.overrun++;
rsr &= uap->port.read_status_mask;
if (rsr & UART01x_RSR_BE)
flag = TTY_BREAK;
else if (rsr & UART01x_RSR_PE)
flag = TTY_PARITY;
else if (rsr & UART01x_RSR_FE)
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char(&uap->port, ch, regs))
goto ignore_char;
uart_insert_char(&uap->port, rsr, UART01x_RSR_OE, ch, flag);
ignore_char:
status = readw(uap->port.membase + UART01x_FR);
}
tty_flip_buffer_push(tty);
return;
}
static void pl011_tx_chars(struct uart_amba_port *uap)
{
struct circ_buf *xmit = &uap->port.info->xmit;
int count;
if (uap->port.x_char) {
writew(uap->port.x_char, uap->port.membase + UART01x_DR);
uap->port.icount.tx++;
uap->port.x_char = 0;
return;
}
if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) {
pl011_stop_tx(&uap->port);
return;
}
count = uap->port.fifosize >> 1;
do {
writew(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
uap->port.icount.tx++;
if (uart_circ_empty(xmit))
break;
} while (--count > 0);
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&uap->port);
if (uart_circ_empty(xmit))
pl011_stop_tx(&uap->port);
}
static void pl011_modem_status(struct uart_amba_port *uap)
{
unsigned int status, delta;
status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
delta = status ^ uap->old_status;
uap->old_status = status;
if (!delta)
return;
if (delta & UART01x_FR_DCD)
uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
if (delta & UART01x_FR_DSR)
uap->port.icount.dsr++;
if (delta & UART01x_FR_CTS)
uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
wake_up_interruptible(&uap->port.info->delta_msr_wait);
}
static irqreturn_t pl011_int(int irq, void *dev_id, struct pt_regs *regs)
{
struct uart_amba_port *uap = dev_id;
unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
int handled = 0;
spin_lock(&uap->port.lock);
status = readw(uap->port.membase + UART011_MIS);
if (status) {
do {
writew(status & ~(UART011_TXIS|UART011_RTIS|
UART011_RXIS),
uap->port.membase + UART011_ICR);
if (status & (UART011_RTIS|UART011_RXIS))
#ifdef SUPPORT_SYSRQ
pl011_rx_chars(uap, regs);
#else
pl011_rx_chars(uap);
#endif
if (status & (UART011_DSRMIS|UART011_DCDMIS|
UART011_CTSMIS|UART011_RIMIS))
pl011_modem_status(uap);
if (status & UART011_TXIS)
pl011_tx_chars(uap);
if (pass_counter-- == 0)
break;
status = readw(uap->port.membase + UART011_MIS);
} while (status != 0);
handled = 1;
}
spin_unlock(&uap->port.lock);
return IRQ_RETVAL(handled);
}
static unsigned int pl01x_tx_empty(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int status = readw(uap->port.membase + UART01x_FR);
return status & (UART01x_FR_BUSY|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT;
}
static unsigned int pl01x_get_mctrl(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int result = 0;
unsigned int status = readw(uap->port.membase + UART01x_FR);
#define BIT(uartbit, tiocmbit) \
if (status & uartbit) \
result |= tiocmbit
BIT(UART01x_FR_DCD, TIOCM_CAR);
BIT(UART01x_FR_DSR, TIOCM_DSR);
BIT(UART01x_FR_CTS, TIOCM_CTS);
BIT(UART011_FR_RI, TIOCM_RNG);
#undef BIT
return result;
}
static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int cr;
cr = readw(uap->port.membase + UART011_CR);
#define BIT(tiocmbit, uartbit) \
if (mctrl & tiocmbit) \
cr |= uartbit; \
else \
cr &= ~uartbit
BIT(TIOCM_RTS, UART011_CR_RTS);
BIT(TIOCM_DTR, UART011_CR_DTR);
BIT(TIOCM_OUT1, UART011_CR_OUT1);
BIT(TIOCM_OUT2, UART011_CR_OUT2);
BIT(TIOCM_LOOP, UART011_CR_LBE);
#undef BIT
writew(cr, uap->port.membase + UART011_CR);
}
static void pl011_break_ctl(struct uart_port *port, int break_state)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned long flags;
unsigned int lcr_h;
spin_lock_irqsave(&uap->port.lock, flags);
lcr_h = readw(uap->port.membase + UART011_LCRH);
if (break_state == -1)
lcr_h |= UART01x_LCRH_BRK;
else
lcr_h &= ~UART01x_LCRH_BRK;
writew(lcr_h, uap->port.membase + UART011_LCRH);
spin_unlock_irqrestore(&uap->port.lock, flags);
}
static int pl011_startup(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int cr;
int retval;
/*
* Try to enable the clock producer.
*/
retval = clk_enable(uap->clk);
if (retval)
goto out;
uap->port.uartclk = clk_get_rate(uap->clk);
/*
* Allocate the IRQ
*/
retval = request_irq(uap->port.irq, pl011_int, 0, "uart-pl011", uap);
if (retval)
goto clk_dis;
writew(UART011_IFLS_RX4_8|UART011_IFLS_TX4_8,
uap->port.membase + UART011_IFLS);
/*
* Provoke TX FIFO interrupt into asserting.
*/
cr = UART01x_CR_UARTEN | UART011_CR_TXE | UART011_CR_LBE;
writew(cr, uap->port.membase + UART011_CR);
writew(0, uap->port.membase + UART011_FBRD);
writew(1, uap->port.membase + UART011_IBRD);
writew(0, uap->port.membase + UART011_LCRH);
writew(0, uap->port.membase + UART01x_DR);
while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY)
barrier();
cr = UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
writew(cr, uap->port.membase + UART011_CR);
/*
* initialise the old status of the modem signals
*/
uap->old_status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
/*
* Finally, enable interrupts
*/
spin_lock_irq(&uap->port.lock);
uap->im = UART011_RXIM | UART011_RTIM;
writew(uap->im, uap->port.membase + UART011_IMSC);
spin_unlock_irq(&uap->port.lock);
return 0;
clk_dis:
clk_disable(uap->clk);
out:
return retval;
}
static void pl011_shutdown(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned long val;
/*
* disable all interrupts
*/
spin_lock_irq(&uap->port.lock);
uap->im = 0;
writew(uap->im, uap->port.membase + UART011_IMSC);
writew(0xffff, uap->port.membase + UART011_ICR);
spin_unlock_irq(&uap->port.lock);
/*
* Free the interrupt
*/
free_irq(uap->port.irq, uap);
/*
* disable the port
*/
writew(UART01x_CR_UARTEN | UART011_CR_TXE, uap->port.membase + UART011_CR);
/*
* disable break condition and fifos
*/
val = readw(uap->port.membase + UART011_LCRH);
val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN);
writew(val, uap->port.membase + UART011_LCRH);
/*
* Shut down the clock producer
*/
clk_disable(uap->clk);
}
static void
pl011_set_termios(struct uart_port *port, struct termios *termios,
struct termios *old)
{
unsigned int lcr_h, old_cr;
unsigned long flags;
unsigned int baud, quot;
/*
* Ask the core to calculate the divisor for us.
*/
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
quot = port->uartclk * 4 / baud;
switch (termios->c_cflag & CSIZE) {
case CS5:
lcr_h = UART01x_LCRH_WLEN_5;
break;
case CS6:
lcr_h = UART01x_LCRH_WLEN_6;
break;
case CS7:
lcr_h = UART01x_LCRH_WLEN_7;
break;
default: // CS8
lcr_h = UART01x_LCRH_WLEN_8;
break;
}
if (termios->c_cflag & CSTOPB)
lcr_h |= UART01x_LCRH_STP2;
if (termios->c_cflag & PARENB) {
lcr_h |= UART01x_LCRH_PEN;
if (!(termios->c_cflag & PARODD))
lcr_h |= UART01x_LCRH_EPS;
}
if (port->fifosize > 1)
lcr_h |= UART01x_LCRH_FEN;
spin_lock_irqsave(&port->lock, flags);
/*
* Update the per-port timeout.
*/
uart_update_timeout(port, termios->c_cflag, baud);
port->read_status_mask = UART01x_RSR_OE;
if (termios->c_iflag & INPCK)
port->read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
if (termios->c_iflag & (BRKINT | PARMRK))
port->read_status_mask |= UART01x_RSR_BE;
/*
* Characters to ignore
*/
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
if (termios->c_iflag & IGNBRK) {
port->ignore_status_mask |= UART01x_RSR_BE;
/*
* If we're ignoring parity and break indicators,
* ignore overruns too (for real raw support).
*/
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |= UART01x_RSR_OE;
}
/*
* Ignore all characters if CREAD is not set.
*/
if ((termios->c_cflag & CREAD) == 0)
port->ignore_status_mask |= UART_DUMMY_RSR_RX;
if (UART_ENABLE_MS(port, termios->c_cflag))
pl011_enable_ms(port);
/* first, disable everything */
old_cr = readw(port->membase + UART011_CR);
writew(0, port->membase + UART011_CR);
/* Set baud rate */
writew(quot & 0x3f, port->membase + UART011_FBRD);
writew(quot >> 6, port->membase + UART011_IBRD);
/*
* ----------v----------v----------v----------v-----
* NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
* ----------^----------^----------^----------^-----
*/
writew(lcr_h, port->membase + UART011_LCRH);
writew(old_cr, port->membase + UART011_CR);
spin_unlock_irqrestore(&port->lock, flags);
}
static const char *pl011_type(struct uart_port *port)
{
return port->type == PORT_AMBA ? "AMBA/PL011" : NULL;
}
/*
* Release the memory region(s) being used by 'port'
*/
static void pl010_release_port(struct uart_port *port)
{
release_mem_region(port->mapbase, SZ_4K);
}
/*
* Request the memory region(s) being used by 'port'
*/
static int pl010_request_port(struct uart_port *port)
{
return request_mem_region(port->mapbase, SZ_4K, "uart-pl011")
!= NULL ? 0 : -EBUSY;
}
/*
* Configure/autoconfigure the port.
*/
static void pl010_config_port(struct uart_port *port, int flags)
{
if (flags & UART_CONFIG_TYPE) {
port->type = PORT_AMBA;
pl010_request_port(port);
}
}
/*
* verify the new serial_struct (for TIOCSSERIAL).
*/
static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
{
int ret = 0;
if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
ret = -EINVAL;
if (ser->irq < 0 || ser->irq >= NR_IRQS)
ret = -EINVAL;
if (ser->baud_base < 9600)
ret = -EINVAL;
return ret;
}
static struct uart_ops amba_pl011_pops = {
.tx_empty = pl01x_tx_empty,
.set_mctrl = pl011_set_mctrl,
.get_mctrl = pl01x_get_mctrl,
.stop_tx = pl011_stop_tx,
.start_tx = pl011_start_tx,
.stop_rx = pl011_stop_rx,
.enable_ms = pl011_enable_ms,
.break_ctl = pl011_break_ctl,
.startup = pl011_startup,
.shutdown = pl011_shutdown,
.set_termios = pl011_set_termios,
.type = pl011_type,
.release_port = pl010_release_port,
.request_port = pl010_request_port,
.config_port = pl010_config_port,
.verify_port = pl010_verify_port,
};
static struct uart_amba_port *amba_ports[UART_NR];
#ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE
static inline void
pl011_console_write_char(struct uart_amba_port *uap, char ch)
{
unsigned int status;
do {
status = readw(uap->port.membase + UART01x_FR);
} while (status & UART01x_FR_TXFF);
writew(ch, uap->port.membase + UART01x_DR);
}
static void
pl011_console_write(struct console *co, const char *s, unsigned int count)
{
struct uart_amba_port *uap = amba_ports[co->index];
unsigned int status, old_cr, new_cr;
int i;
clk_enable(uap->clk);
/*
* First save the CR then disable the interrupts
*/
old_cr = readw(uap->port.membase + UART011_CR);
new_cr = old_cr & ~UART011_CR_CTSEN;
new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
writew(new_cr, uap->port.membase + UART011_CR);
/*
* Now, do each character
*/
for (i = 0; i < count; i++) {
pl011_console_write_char(uap, s[i]);
if (s[i] == '\n')
pl011_console_write_char(uap, '\r');
}
/*
* Finally, wait for transmitter to become empty
* and restore the TCR
*/
do {
status = readw(uap->port.membase + UART01x_FR);
} while (status & UART01x_FR_BUSY);
writew(old_cr, uap->port.membase + UART011_CR);
clk_disable(uap->clk);
}
static void __init
pl011_console_get_options(struct uart_amba_port *uap, int *baud,
int *parity, int *bits)
{
if (readw(uap->port.membase + UART011_CR) & UART01x_CR_UARTEN) {
unsigned int lcr_h, ibrd, fbrd;
lcr_h = readw(uap->port.membase + UART011_LCRH);
*parity = 'n';
if (lcr_h & UART01x_LCRH_PEN) {
if (lcr_h & UART01x_LCRH_EPS)
*parity = 'e';
else
*parity = 'o';
}
if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
*bits = 7;
else
*bits = 8;
ibrd = readw(uap->port.membase + UART011_IBRD);
fbrd = readw(uap->port.membase + UART011_FBRD);
*baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd);
}
}
static int __init pl011_console_setup(struct console *co, char *options)
{
struct uart_amba_port *uap;
int baud = 38400;
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 >= UART_NR)
co->index = 0;
uap = amba_ports[co->index];
uap->port.uartclk = clk_get_rate(uap->clk);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
pl011_console_get_options(uap, &baud, &parity, &bits);
return uart_set_options(&uap->port, co, baud, parity, bits, flow);
}
extern struct uart_driver amba_reg;
static struct console amba_console = {
.name = "ttyAMA",
.write = pl011_console_write,
.device = uart_console_device,
.setup = pl011_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &amba_reg,
};
#define AMBA_CONSOLE (&amba_console)
#else
#define AMBA_CONSOLE NULL
#endif
static struct uart_driver amba_reg = {
.owner = THIS_MODULE,
.driver_name = "ttyAMA",
.dev_name = "ttyAMA",
.major = SERIAL_AMBA_MAJOR,
.minor = SERIAL_AMBA_MINOR,
.nr = UART_NR,
.cons = AMBA_CONSOLE,
};
static int pl011_probe(struct amba_device *dev, void *id)
{
struct uart_amba_port *uap;
void __iomem *base;
int i, ret;
for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
if (amba_ports[i] == NULL)
break;
if (i == ARRAY_SIZE(amba_ports)) {
ret = -EBUSY;
goto out;
}
uap = kmalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
if (uap == NULL) {
ret = -ENOMEM;
goto out;
}
base = ioremap(dev->res.start, PAGE_SIZE);
if (!base) {
ret = -ENOMEM;
goto free;
}
memset(uap, 0, sizeof(struct uart_amba_port));
uap->clk = clk_get(&dev->dev, "UARTCLK");
if (IS_ERR(uap->clk)) {
ret = PTR_ERR(uap->clk);
goto unmap;
}
ret = clk_use(uap->clk);
if (ret)
goto putclk;
uap->port.dev = &dev->dev;
uap->port.mapbase = dev->res.start;
uap->port.membase = base;
uap->port.iotype = UPIO_MEM;
uap->port.irq = dev->irq[0];
uap->port.fifosize = 16;
uap->port.ops = &amba_pl011_pops;
uap->port.flags = UPF_BOOT_AUTOCONF;
uap->port.line = i;
amba_ports[i] = uap;
amba_set_drvdata(dev, uap);
ret = uart_add_one_port(&amba_reg, &uap->port);
if (ret) {
amba_set_drvdata(dev, NULL);
amba_ports[i] = NULL;
clk_unuse(uap->clk);
putclk:
clk_put(uap->clk);
unmap:
iounmap(base);
free:
kfree(uap);
}
out:
return ret;
}
static int pl011_remove(struct amba_device *dev)
{
struct uart_amba_port *uap = amba_get_drvdata(dev);
int i;
amba_set_drvdata(dev, NULL);
uart_remove_one_port(&amba_reg, &uap->port);
for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
if (amba_ports[i] == uap)
amba_ports[i] = NULL;
iounmap(uap->port.membase);
clk_unuse(uap->clk);
clk_put(uap->clk);
kfree(uap);
return 0;
}
static struct amba_id pl011_ids[] __initdata = {
{
.id = 0x00041011,
.mask = 0x000fffff,
},
{ 0, 0 },
};
static struct amba_driver pl011_driver = {
.drv = {
.name = "uart-pl011",
},
.id_table = pl011_ids,
.probe = pl011_probe,
.remove = pl011_remove,
};
static int __init pl011_init(void)
{
int ret;
printk(KERN_INFO "Serial: AMBA PL011 UART driver\n");
ret = uart_register_driver(&amba_reg);
if (ret == 0) {
ret = amba_driver_register(&pl011_driver);
if (ret)
uart_unregister_driver(&amba_reg);
}
return ret;
}
static void __exit pl011_exit(void)
{
amba_driver_unregister(&pl011_driver);
uart_unregister_driver(&amba_reg);
}
module_init(pl011_init);
module_exit(pl011_exit);
MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
MODULE_DESCRIPTION("ARM AMBA serial port driver");
MODULE_LICENSE("GPL");
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