linux/drivers/tty/serial/amba-pl010.c

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/*
* 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
*
* 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.
*/
#if defined(CONFIG_SERIAL_AMBA_PL010_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 <linux/amba/bus.h>
#include <linux/amba/serial.h>
#include <linux/clk.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <asm/io.h>
#define UART_NR 8
#define SERIAL_AMBA_MAJOR 204
#define SERIAL_AMBA_MINOR 16
#define SERIAL_AMBA_NR UART_NR
#define AMBA_ISR_PASS_LIMIT 256
#define UART_RX_DATA(s) (((s) & UART01x_FR_RXFE) == 0)
#define UART_TX_READY(s) (((s) & UART01x_FR_TXFF) == 0)
#define UART_DUMMY_RSR_RX 256
#define UART_PORT_SIZE 64
/*
* We wrap our port structure around the generic uart_port.
*/
struct uart_amba_port {
struct uart_port port;
struct clk *clk;
struct amba_device *dev;
struct amba_pl010_data *data;
unsigned int old_status;
};
static void pl010_stop_tx(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int cr;
cr = readb(uap->port.membase + UART010_CR);
cr &= ~UART010_CR_TIE;
writel(cr, uap->port.membase + UART010_CR);
}
static void pl010_start_tx(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int cr;
cr = readb(uap->port.membase + UART010_CR);
cr |= UART010_CR_TIE;
writel(cr, uap->port.membase + UART010_CR);
}
static void pl010_stop_rx(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int cr;
cr = readb(uap->port.membase + UART010_CR);
cr &= ~(UART010_CR_RIE | UART010_CR_RTIE);
writel(cr, uap->port.membase + UART010_CR);
}
static void pl010_enable_ms(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int cr;
cr = readb(uap->port.membase + UART010_CR);
cr |= UART010_CR_MSIE;
writel(cr, uap->port.membase + UART010_CR);
}
static void pl010_rx_chars(struct uart_amba_port *uap)
{
unsigned int status, ch, flag, rsr, max_count = 256;
status = readb(uap->port.membase + UART01x_FR);
while (UART_RX_DATA(status) && max_count--) {
ch = readb(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 = readb(uap->port.membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
if (unlikely(rsr & UART01x_RSR_ANY)) {
writel(0, uap->port.membase + UART01x_ECR);
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))
goto ignore_char;
uart_insert_char(&uap->port, rsr, UART01x_RSR_OE, ch, flag);
ignore_char:
status = readb(uap->port.membase + UART01x_FR);
}
spin_unlock(&uap->port.lock);
tty_flip_buffer_push(&uap->port.state->port);
spin_lock(&uap->port.lock);
}
static void pl010_tx_chars(struct uart_amba_port *uap)
{
struct circ_buf *xmit = &uap->port.state->xmit;
int count;
if (uap->port.x_char) {
writel(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)) {
pl010_stop_tx(&uap->port);
return;
}
count = uap->port.fifosize >> 1;
do {
writel(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))
pl010_stop_tx(&uap->port);
}
static void pl010_modem_status(struct uart_amba_port *uap)
{
unsigned int status, delta;
writel(0, uap->port.membase + UART010_ICR);
status = readb(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.state->port.delta_msr_wait);
}
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 21:55:46 +08:00
static irqreturn_t pl010_int(int irq, void *dev_id)
{
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 = readb(uap->port.membase + UART010_IIR);
if (status) {
do {
if (status & (UART010_IIR_RTIS | UART010_IIR_RIS))
pl010_rx_chars(uap);
if (status & UART010_IIR_MIS)
pl010_modem_status(uap);
if (status & UART010_IIR_TIS)
pl010_tx_chars(uap);
if (pass_counter-- == 0)
break;
status = readb(uap->port.membase + UART010_IIR);
} while (status & (UART010_IIR_RTIS | UART010_IIR_RIS |
UART010_IIR_TIS));
handled = 1;
}
spin_unlock(&uap->port.lock);
return IRQ_RETVAL(handled);
}
static unsigned int pl010_tx_empty(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int status = readb(uap->port.membase + UART01x_FR);
return status & UART01x_FR_BUSY ? 0 : TIOCSER_TEMT;
}
static unsigned int pl010_get_mctrl(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int result = 0;
unsigned int status;
status = readb(uap->port.membase + UART01x_FR);
if (status & UART01x_FR_DCD)
result |= TIOCM_CAR;
if (status & UART01x_FR_DSR)
result |= TIOCM_DSR;
if (status & UART01x_FR_CTS)
result |= TIOCM_CTS;
return result;
}
static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
if (uap->data)
uap->data->set_mctrl(uap->dev, uap->port.membase, mctrl);
}
static void pl010_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 = readb(uap->port.membase + UART010_LCRH);
if (break_state == -1)
lcr_h |= UART01x_LCRH_BRK;
else
lcr_h &= ~UART01x_LCRH_BRK;
writel(lcr_h, uap->port.membase + UART010_LCRH);
spin_unlock_irqrestore(&uap->port.lock, flags);
}
static int pl010_startup(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
int retval;
/*
* Try to enable the clock producer.
*/
retval = clk_prepare_enable(uap->clk);
if (retval)
goto out;
uap->port.uartclk = clk_get_rate(uap->clk);
/*
* Allocate the IRQ
*/
retval = request_irq(uap->port.irq, pl010_int, 0, "uart-pl010", uap);
if (retval)
goto clk_dis;
/*
* initialise the old status of the modem signals
*/
uap->old_status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
/*
* Finally, enable interrupts
*/
writel(UART01x_CR_UARTEN | UART010_CR_RIE | UART010_CR_RTIE,
uap->port.membase + UART010_CR);
return 0;
clk_dis:
clk_disable_unprepare(uap->clk);
out:
return retval;
}
static void pl010_shutdown(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
/*
* Free the interrupt
*/
free_irq(uap->port.irq, uap);
/*
* disable all interrupts, disable the port
*/
writel(0, uap->port.membase + UART010_CR);
/* disable break condition and fifos */
writel(readb(uap->port.membase + UART010_LCRH) &
~(UART01x_LCRH_BRK | UART01x_LCRH_FEN),
uap->port.membase + UART010_LCRH);
/*
* Shut down the clock producer
*/
clk_disable_unprepare(uap->clk);
}
static void
pl010_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
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, uap->port.uartclk/16);
quot = uart_get_divisor(port, 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 (uap->port.fifosize > 1)
lcr_h |= UART01x_LCRH_FEN;
spin_lock_irqsave(&uap->port.lock, flags);
/*
* Update the per-port timeout.
*/
uart_update_timeout(port, termios->c_cflag, baud);
uap->port.read_status_mask = UART01x_RSR_OE;
if (termios->c_iflag & INPCK)
uap->port.read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
if (termios->c_iflag & (BRKINT | PARMRK))
uap->port.read_status_mask |= UART01x_RSR_BE;
/*
* Characters to ignore
*/
uap->port.ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
uap->port.ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
if (termios->c_iflag & IGNBRK) {
uap->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)
uap->port.ignore_status_mask |= UART01x_RSR_OE;
}
/*
* Ignore all characters if CREAD is not set.
*/
if ((termios->c_cflag & CREAD) == 0)
uap->port.ignore_status_mask |= UART_DUMMY_RSR_RX;
/* first, disable everything */
old_cr = readb(uap->port.membase + UART010_CR) & ~UART010_CR_MSIE;
if (UART_ENABLE_MS(port, termios->c_cflag))
old_cr |= UART010_CR_MSIE;
writel(0, uap->port.membase + UART010_CR);
/* Set baud rate */
quot -= 1;
writel((quot & 0xf00) >> 8, uap->port.membase + UART010_LCRM);
writel(quot & 0xff, uap->port.membase + UART010_LCRL);
/*
* ----------v----------v----------v----------v-----
* NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
* ----------^----------^----------^----------^-----
*/
writel(lcr_h, uap->port.membase + UART010_LCRH);
writel(old_cr, uap->port.membase + UART010_CR);
spin_unlock_irqrestore(&uap->port.lock, flags);
}
static void pl010_set_ldisc(struct uart_port *port, int new)
{
if (new == N_PPS) {
port->flags |= UPF_HARDPPS_CD;
pl010_enable_ms(port);
} else
port->flags &= ~UPF_HARDPPS_CD;
}
static const char *pl010_type(struct uart_port *port)
{
return port->type == PORT_AMBA ? "AMBA" : NULL;
}
/*
* Release the memory region(s) being used by 'port'
*/
static void pl010_release_port(struct uart_port *port)
{
release_mem_region(port->mapbase, UART_PORT_SIZE);
}
/*
* Request the memory region(s) being used by 'port'
*/
static int pl010_request_port(struct uart_port *port)
{
return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010")
!= 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_pl010_pops = {
.tx_empty = pl010_tx_empty,
.set_mctrl = pl010_set_mctrl,
.get_mctrl = pl010_get_mctrl,
.stop_tx = pl010_stop_tx,
.start_tx = pl010_start_tx,
.stop_rx = pl010_stop_rx,
.enable_ms = pl010_enable_ms,
.break_ctl = pl010_break_ctl,
.startup = pl010_startup,
.shutdown = pl010_shutdown,
.set_termios = pl010_set_termios,
.set_ldisc = pl010_set_ldisc,
.type = pl010_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_PL010_CONSOLE
static void pl010_console_putchar(struct uart_port *port, int ch)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int status;
do {
status = readb(uap->port.membase + UART01x_FR);
barrier();
} while (!UART_TX_READY(status));
writel(ch, uap->port.membase + UART01x_DR);
}
static void
pl010_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;
clk_enable(uap->clk);
/*
* First save the CR then disable the interrupts
*/
old_cr = readb(uap->port.membase + UART010_CR);
writel(UART01x_CR_UARTEN, uap->port.membase + UART010_CR);
uart_console_write(&uap->port, s, count, pl010_console_putchar);
/*
* Finally, wait for transmitter to become empty
* and restore the TCR
*/
do {
status = readb(uap->port.membase + UART01x_FR);
barrier();
} while (status & UART01x_FR_BUSY);
writel(old_cr, uap->port.membase + UART010_CR);
clk_disable(uap->clk);
}
static void __init
pl010_console_get_options(struct uart_amba_port *uap, int *baud,
int *parity, int *bits)
{
if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) {
unsigned int lcr_h, quot;
lcr_h = readb(uap->port.membase + UART010_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;
quot = readb(uap->port.membase + UART010_LCRL) |
readb(uap->port.membase + UART010_LCRM) << 8;
*baud = uap->port.uartclk / (16 * (quot + 1));
}
}
static int __init pl010_console_setup(struct console *co, char *options)
{
struct uart_amba_port *uap;
int baud = 38400;
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 >= UART_NR)
co->index = 0;
uap = amba_ports[co->index];
if (!uap)
return -ENODEV;
ret = clk_prepare(uap->clk);
if (ret)
return ret;
uap->port.uartclk = clk_get_rate(uap->clk);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
pl010_console_get_options(uap, &baud, &parity, &bits);
return uart_set_options(&uap->port, co, baud, parity, bits, flow);
}
static struct uart_driver amba_reg;
static struct console amba_console = {
.name = "ttyAM",
.write = pl010_console_write,
.device = uart_console_device,
.setup = pl010_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 = "ttyAM",
.dev_name = "ttyAM",
.major = SERIAL_AMBA_MAJOR,
.minor = SERIAL_AMBA_MINOR,
.nr = UART_NR,
.cons = AMBA_CONSOLE,
};
static int pl010_probe(struct amba_device *dev, const struct amba_id *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 = kzalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
if (!uap) {
ret = -ENOMEM;
goto out;
}
base = ioremap(dev->res.start, resource_size(&dev->res));
if (!base) {
ret = -ENOMEM;
goto free;
}
uap->clk = clk_get(&dev->dev, NULL);
if (IS_ERR(uap->clk)) {
ret = PTR_ERR(uap->clk);
goto unmap;
}
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_pl010_pops;
uap->port.flags = UPF_BOOT_AUTOCONF;
uap->port.line = i;
uap->dev = dev;
uap->data = dev_get_platdata(&dev->dev);
amba_ports[i] = uap;
amba_set_drvdata(dev, uap);
ret = uart_add_one_port(&amba_reg, &uap->port);
if (ret) {
amba_ports[i] = NULL;
clk_put(uap->clk);
unmap:
iounmap(base);
free:
kfree(uap);
}
out:
return ret;
}
static int pl010_remove(struct amba_device *dev)
{
struct uart_amba_port *uap = amba_get_drvdata(dev);
int i;
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_put(uap->clk);
kfree(uap);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int pl010_suspend(struct device *dev)
{
struct uart_amba_port *uap = dev_get_drvdata(dev);
if (uap)
uart_suspend_port(&amba_reg, &uap->port);
return 0;
}
static int pl010_resume(struct device *dev)
{
struct uart_amba_port *uap = dev_get_drvdata(dev);
if (uap)
uart_resume_port(&amba_reg, &uap->port);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(pl010_dev_pm_ops, pl010_suspend, pl010_resume);
static struct amba_id pl010_ids[] = {
{
.id = 0x00041010,
.mask = 0x000fffff,
},
{ 0, 0 },
};
MODULE_DEVICE_TABLE(amba, pl010_ids);
static struct amba_driver pl010_driver = {
.drv = {
.name = "uart-pl010",
.pm = &pl010_dev_pm_ops,
},
.id_table = pl010_ids,
.probe = pl010_probe,
.remove = pl010_remove,
};
static int __init pl010_init(void)
{
int ret;
printk(KERN_INFO "Serial: AMBA driver\n");
ret = uart_register_driver(&amba_reg);
if (ret == 0) {
ret = amba_driver_register(&pl010_driver);
if (ret)
uart_unregister_driver(&amba_reg);
}
return ret;
}
static void __exit pl010_exit(void)
{
amba_driver_unregister(&pl010_driver);
uart_unregister_driver(&amba_reg);
}
module_init(pl010_init);
module_exit(pl010_exit);
MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
MODULE_DESCRIPTION("ARM AMBA serial port driver");
MODULE_LICENSE("GPL");