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linux/drivers/serial/sa1100.c
Alan Cox 33f0f88f1c [PATCH] TTY layer buffering revamp 
The API and code have been through various bits of initial review by
serial driver people but they definitely need to live somewhere for a
while so the unconverted drivers can get knocked into shape, existing
drivers that have been updated can be better tuned and bugs whacked out.

This replaces the tty flip buffers with kmalloc objects in rings. In the
normal situation for an IRQ driven serial port at typical speeds the
behaviour is pretty much the same, two buffers end up allocated and the
kernel cycles between them as before.

When there are delays or at high speed we now behave far better as the
buffer pool can grow a bit rather than lose characters. This also means
that we can operate at higher speeds reliably.

For drivers that receive characters in blocks (DMA based, USB and
especially virtualisation) the layer allows a lot of driver specific
code that works around the tty layer with private secondary queues to be
removed. The IBM folks need this sort of layer, the smart serial port
people do, the virtualisers do (because a virtualised tty typically
operates at infinite speed rather than emulating 9600 baud).

Finally many drivers had invalid and unsafe attempts to avoid buffer
overflows by directly invoking tty methods extracted out of the innards
of work queue structs. These are no longer needed and all go away. That
fixes various random hangs with serial ports on overflow.

The other change in here is to optimise the receive_room path that is
used by some callers. It turns out that only one ldisc uses receive room
except asa constant and it updates it far far less than the value is
read. We thus make it a variable not a function call.

I expect the code to contain bugs due to the size alone but I'll be
watching and squashing them and feeding out new patches as it goes.

Because the buffers now dynamically expand you should only run out of
buffering when the kernel runs out of memory for real.  That means a lot of
the horrible hacks high performance drivers used to do just aren't needed any
more.

Description:

tty_insert_flip_char is an old API and continues to work as before, as does
tty_flip_buffer_push() [this is why many drivers dont need modification].  It
does now also return the number of chars inserted

There are also

tty_buffer_request_room(tty, len)

which asks for a buffer block of the length requested and returns the space
found.  This improves efficiency with hardware that knows how much to
transfer.

and tty_insert_flip_string_flags(tty, str, flags, len)

to insert a string of characters and flags

For a smart interface the usual code is

    len = tty_request_buffer_room(tty, amount_hardware_says);
    tty_insert_flip_string(tty, buffer_from_card, len);

More description!

At the moment tty buffers are attached directly to the tty.  This is causing a
lot of the problems related to tty layer locking, also problems at high speed
and also with bursty data (such as occurs in virtualised environments)

I'm working on ripping out the flip buffers and replacing them with a pool of
dynamically allocated buffers.  This allows both for old style "byte I/O"
devices and also helps virtualisation and smart devices where large blocks of
data suddenely materialise and need storing.

So far so good.  Lots of drivers reference tty->flip.*.  Several of them also
call directly and unsafely into function pointers it provides.  This will all
break.  Most drivers can use tty_insert_flip_char which can be kept as an API
but others need more.

At the moment I've added the following interfaces, if people think more will
be needed now is a good time to say

 int tty_buffer_request_room(tty, size)

Try and ensure at least size bytes are available, returns actual room (may be
zero).  At the moment it just uses the flipbuf space but that will change.
Repeated calls without characters being added are not cumulative.  (ie if you
call it with 1, 1, 1, and then 4 you'll have four characters of space.  The
other functions will also try and grow buffers in future but this will be a
more efficient way when you know block sizes.

 int tty_insert_flip_char(tty, ch, flag)

As before insert a character if there is room.  Now returns 1 for success, 0
for failure.

 int tty_insert_flip_string(tty, str, len)

Insert a block of non error characters.  Returns the number inserted.

 int tty_prepare_flip_string(tty, strptr, len)

Adjust the buffer to allow len characters to be added.  Returns a buffer
pointer in strptr and the length available.  This allows for hardware that
needs to use functions like insl or mencpy_fromio.

Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:59 -08:00

928 lines
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/*
* linux/drivers/char/sa1100.c
*
* Driver for SA11x0 serial ports
*
* Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
*
* 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: sa1100.c,v 1.50 2002/07/29 14:41:04 rmk Exp $
*
*/
#include <linux/config.h>
#if defined(CONFIG_SERIAL_SA1100_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>
#include <asm/mach/serial_sa1100.h>
/* We've been assigned a range on the "Low-density serial ports" major */
#define SERIAL_SA1100_MAJOR 204
#define MINOR_START 5
#define NR_PORTS 3
#define SA1100_ISR_PASS_LIMIT 256
/*
* Convert from ignore_status_mask or read_status_mask to UTSR[01]
*/
#define SM_TO_UTSR0(x) ((x) & 0xff)
#define SM_TO_UTSR1(x) ((x) >> 8)
#define UTSR0_TO_SM(x) ((x))
#define UTSR1_TO_SM(x) ((x) << 8)
#define UART_GET_UTCR0(sport) __raw_readl((sport)->port.membase + UTCR0)
#define UART_GET_UTCR1(sport) __raw_readl((sport)->port.membase + UTCR1)
#define UART_GET_UTCR2(sport) __raw_readl((sport)->port.membase + UTCR2)
#define UART_GET_UTCR3(sport) __raw_readl((sport)->port.membase + UTCR3)
#define UART_GET_UTSR0(sport) __raw_readl((sport)->port.membase + UTSR0)
#define UART_GET_UTSR1(sport) __raw_readl((sport)->port.membase + UTSR1)
#define UART_GET_CHAR(sport) __raw_readl((sport)->port.membase + UTDR)
#define UART_PUT_UTCR0(sport,v) __raw_writel((v),(sport)->port.membase + UTCR0)
#define UART_PUT_UTCR1(sport,v) __raw_writel((v),(sport)->port.membase + UTCR1)
#define UART_PUT_UTCR2(sport,v) __raw_writel((v),(sport)->port.membase + UTCR2)
#define UART_PUT_UTCR3(sport,v) __raw_writel((v),(sport)->port.membase + UTCR3)
#define UART_PUT_UTSR0(sport,v) __raw_writel((v),(sport)->port.membase + UTSR0)
#define UART_PUT_UTSR1(sport,v) __raw_writel((v),(sport)->port.membase + UTSR1)
#define UART_PUT_CHAR(sport,v) __raw_writel((v),(sport)->port.membase + UTDR)
/*
* This is the size of our serial port register set.
*/
#define UART_PORT_SIZE 0x24
/*
* 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)
struct sa1100_port {
struct uart_port port;
struct timer_list timer;
unsigned int old_status;
};
/*
* Handle any change of modem status signal since we were last called.
*/
static void sa1100_mctrl_check(struct sa1100_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 sa1100_timeout(unsigned long data)
{
struct sa1100_port *sport = (struct sa1100_port *)data;
unsigned long flags;
if (sport->port.info) {
spin_lock_irqsave(&sport->port.lock, flags);
sa1100_mctrl_check(sport);
spin_unlock_irqrestore(&sport->port.lock, flags);
mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
}
}
/*
* interrupts disabled on entry
*/
static void sa1100_stop_tx(struct uart_port *port)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
u32 utcr3;
utcr3 = UART_GET_UTCR3(sport);
UART_PUT_UTCR3(sport, utcr3 & ~UTCR3_TIE);
sport->port.read_status_mask &= ~UTSR0_TO_SM(UTSR0_TFS);
}
/*
* port locked and interrupts disabled
*/
static void sa1100_start_tx(struct uart_port *port)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
u32 utcr3;
utcr3 = UART_GET_UTCR3(sport);
sport->port.read_status_mask |= UTSR0_TO_SM(UTSR0_TFS);
UART_PUT_UTCR3(sport, utcr3 | UTCR3_TIE);
}
/*
* Interrupts enabled
*/
static void sa1100_stop_rx(struct uart_port *port)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
u32 utcr3;
utcr3 = UART_GET_UTCR3(sport);
UART_PUT_UTCR3(sport, utcr3 & ~UTCR3_RIE);
}
/*
* Set the modem control timer to fire immediately.
*/
static void sa1100_enable_ms(struct uart_port *port)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
mod_timer(&sport->timer, jiffies);
}
static void
sa1100_rx_chars(struct sa1100_port *sport, struct pt_regs *regs)
{
struct tty_struct *tty = sport->port.info->tty;
unsigned int status, ch, flg;
status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
UTSR0_TO_SM(UART_GET_UTSR0(sport));
while (status & UTSR1_TO_SM(UTSR1_RNE)) {
ch = UART_GET_CHAR(sport);
sport->port.icount.rx++;
flg = TTY_NORMAL;
/*
* note that the error handling code is
* out of the main execution path
*/
if (status & UTSR1_TO_SM(UTSR1_PRE | UTSR1_FRE | UTSR1_ROR)) {
if (status & UTSR1_TO_SM(UTSR1_PRE))
sport->port.icount.parity++;
else if (status & UTSR1_TO_SM(UTSR1_FRE))
sport->port.icount.frame++;
if (status & UTSR1_TO_SM(UTSR1_ROR))
sport->port.icount.overrun++;
status &= sport->port.read_status_mask;
if (status & UTSR1_TO_SM(UTSR1_PRE))
flg = TTY_PARITY;
else if (status & UTSR1_TO_SM(UTSR1_FRE))
flg = TTY_FRAME;
#ifdef SUPPORT_SYSRQ
sport->port.sysrq = 0;
#endif
}
if (uart_handle_sysrq_char(&sport->port, ch, regs))
goto ignore_char;
uart_insert_char(&sport->port, status, UTSR1_TO_SM(UTSR1_ROR), ch, flg);
ignore_char:
status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
UTSR0_TO_SM(UART_GET_UTSR0(sport));
}
tty_flip_buffer_push(tty);
}
static void sa1100_tx_chars(struct sa1100_port *sport)
{
struct circ_buf *xmit = &sport->port.info->xmit;
if (sport->port.x_char) {
UART_PUT_CHAR(sport, sport->port.x_char);
sport->port.icount.tx++;
sport->port.x_char = 0;
return;
}
/*
* Check the modem control lines before
* transmitting anything.
*/
sa1100_mctrl_check(sport);
if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
sa1100_stop_tx(&sport->port);
return;
}
/*
* Tried using FIFO (not checking TNF) for fifo fill:
* still had the '4 bytes repeated' problem.
*/
while (UART_GET_UTSR1(sport) & UTSR1_TNF) {
UART_PUT_CHAR(sport, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
sport->port.icount.tx++;
if (uart_circ_empty(xmit))
break;
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&sport->port);
if (uart_circ_empty(xmit))
sa1100_stop_tx(&sport->port);
}
static irqreturn_t sa1100_int(int irq, void *dev_id, struct pt_regs *regs)
{
struct sa1100_port *sport = dev_id;
unsigned int status, pass_counter = 0;
spin_lock(&sport->port.lock);
status = UART_GET_UTSR0(sport);
status &= SM_TO_UTSR0(sport->port.read_status_mask) | ~UTSR0_TFS;
do {
if (status & (UTSR0_RFS | UTSR0_RID)) {
/* Clear the receiver idle bit, if set */
if (status & UTSR0_RID)
UART_PUT_UTSR0(sport, UTSR0_RID);
sa1100_rx_chars(sport, regs);
}
/* Clear the relevant break bits */
if (status & (UTSR0_RBB | UTSR0_REB))
UART_PUT_UTSR0(sport, status & (UTSR0_RBB | UTSR0_REB));
if (status & UTSR0_RBB)
sport->port.icount.brk++;
if (status & UTSR0_REB)
uart_handle_break(&sport->port);
if (status & UTSR0_TFS)
sa1100_tx_chars(sport);
if (pass_counter++ > SA1100_ISR_PASS_LIMIT)
break;
status = UART_GET_UTSR0(sport);
status &= SM_TO_UTSR0(sport->port.read_status_mask) |
~UTSR0_TFS;
} while (status & (UTSR0_TFS | UTSR0_RFS | UTSR0_RID));
spin_unlock(&sport->port.lock);
return IRQ_HANDLED;
}
/*
* Return TIOCSER_TEMT when transmitter is not busy.
*/
static unsigned int sa1100_tx_empty(struct uart_port *port)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
return UART_GET_UTSR1(sport) & UTSR1_TBY ? 0 : TIOCSER_TEMT;
}
static unsigned int sa1100_get_mctrl(struct uart_port *port)
{
return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
}
static void sa1100_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
}
/*
* Interrupts always disabled.
*/
static void sa1100_break_ctl(struct uart_port *port, int break_state)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
unsigned long flags;
unsigned int utcr3;
spin_lock_irqsave(&sport->port.lock, flags);
utcr3 = UART_GET_UTCR3(sport);
if (break_state == -1)
utcr3 |= UTCR3_BRK;
else
utcr3 &= ~UTCR3_BRK;
UART_PUT_UTCR3(sport, utcr3);
spin_unlock_irqrestore(&sport->port.lock, flags);
}
static int sa1100_startup(struct uart_port *port)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
int retval;
/*
* Allocate the IRQ
*/
retval = request_irq(sport->port.irq, sa1100_int, 0,
"sa11x0-uart", sport);
if (retval)
return retval;
/*
* Finally, clear and enable interrupts
*/
UART_PUT_UTSR0(sport, -1);
UART_PUT_UTCR3(sport, UTCR3_RXE | UTCR3_TXE | UTCR3_RIE);
/*
* Enable modem status interrupts
*/
spin_lock_irq(&sport->port.lock);
sa1100_enable_ms(&sport->port);
spin_unlock_irq(&sport->port.lock);
return 0;
}
static void sa1100_shutdown(struct uart_port *port)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
/*
* Stop our timer.
*/
del_timer_sync(&sport->timer);
/*
* Free the interrupt
*/
free_irq(sport->port.irq, sport);
/*
* Disable all interrupts, port and break condition.
*/
UART_PUT_UTCR3(sport, 0);
}
static void
sa1100_set_termios(struct uart_port *port, struct termios *termios,
struct termios *old)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
unsigned long flags;
unsigned int utcr0, old_utcr3, baud, quot;
unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
/*
* 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)
utcr0 = UTCR0_DSS;
else
utcr0 = 0;
if (termios->c_cflag & CSTOPB)
utcr0 |= UTCR0_SBS;
if (termios->c_cflag & PARENB) {
utcr0 |= UTCR0_PE;
if (!(termios->c_cflag & PARODD))
utcr0 |= UTCR0_OES;
}
/*
* 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 &= UTSR0_TO_SM(UTSR0_TFS);
sport->port.read_status_mask |= UTSR1_TO_SM(UTSR1_ROR);
if (termios->c_iflag & INPCK)
sport->port.read_status_mask |=
UTSR1_TO_SM(UTSR1_FRE | UTSR1_PRE);
if (termios->c_iflag & (BRKINT | PARMRK))
sport->port.read_status_mask |=
UTSR0_TO_SM(UTSR0_RBB | UTSR0_REB);
/*
* Characters to ignore
*/
sport->port.ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
sport->port.ignore_status_mask |=
UTSR1_TO_SM(UTSR1_FRE | UTSR1_PRE);
if (termios->c_iflag & IGNBRK) {
sport->port.ignore_status_mask |=
UTSR0_TO_SM(UTSR0_RBB | UTSR0_REB);
/*
* 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 |=
UTSR1_TO_SM(UTSR1_ROR);
}
del_timer_sync(&sport->timer);
/*
* Update the per-port timeout.
*/
uart_update_timeout(port, termios->c_cflag, baud);
/*
* disable interrupts and drain transmitter
*/
old_utcr3 = UART_GET_UTCR3(sport);
UART_PUT_UTCR3(sport, old_utcr3 & ~(UTCR3_RIE | UTCR3_TIE));
while (UART_GET_UTSR1(sport) & UTSR1_TBY)
barrier();
/* then, disable everything */
UART_PUT_UTCR3(sport, 0);
/* set the parity, stop bits and data size */
UART_PUT_UTCR0(sport, utcr0);
/* set the baud rate */
quot -= 1;
UART_PUT_UTCR1(sport, ((quot & 0xf00) >> 8));
UART_PUT_UTCR2(sport, (quot & 0xff));
UART_PUT_UTSR0(sport, -1);
UART_PUT_UTCR3(sport, old_utcr3);
if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
sa1100_enable_ms(&sport->port);
spin_unlock_irqrestore(&sport->port.lock, flags);
}
static const char *sa1100_type(struct uart_port *port)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
return sport->port.type == PORT_SA1100 ? "SA1100" : NULL;
}
/*
* Release the memory region(s) being used by 'port'.
*/
static void sa1100_release_port(struct uart_port *port)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
release_mem_region(sport->port.mapbase, UART_PORT_SIZE);
}
/*
* Request the memory region(s) being used by 'port'.
*/
static int sa1100_request_port(struct uart_port *port)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
return request_mem_region(sport->port.mapbase, UART_PORT_SIZE,
"sa11x0-uart") != NULL ? 0 : -EBUSY;
}
/*
* Configure/autoconfigure the port.
*/
static void sa1100_config_port(struct uart_port *port, int flags)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
if (flags & UART_CONFIG_TYPE &&
sa1100_request_port(&sport->port) == 0)
sport->port.type = PORT_SA1100;
}
/*
* Verify the new serial_struct (for TIOCSSERIAL).
* The only change we allow are to the flags and type, and
* even then only between PORT_SA1100 and PORT_UNKNOWN
*/
static int
sa1100_verify_port(struct uart_port *port, struct serial_struct *ser)
{
struct sa1100_port *sport = (struct sa1100_port *)port;
int ret = 0;
if (ser->type != PORT_UNKNOWN && ser->type != PORT_SA1100)
ret = -EINVAL;
if (sport->port.irq != ser->irq)
ret = -EINVAL;
if (ser->io_type != SERIAL_IO_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 sa1100_pops = {
.tx_empty = sa1100_tx_empty,
.set_mctrl = sa1100_set_mctrl,
.get_mctrl = sa1100_get_mctrl,
.stop_tx = sa1100_stop_tx,
.start_tx = sa1100_start_tx,
.stop_rx = sa1100_stop_rx,
.enable_ms = sa1100_enable_ms,
.break_ctl = sa1100_break_ctl,
.startup = sa1100_startup,
.shutdown = sa1100_shutdown,
.set_termios = sa1100_set_termios,
.type = sa1100_type,
.release_port = sa1100_release_port,
.request_port = sa1100_request_port,
.config_port = sa1100_config_port,
.verify_port = sa1100_verify_port,
};
static struct sa1100_port sa1100_ports[NR_PORTS];
/*
* Setup the SA1100 serial ports. Note that we don't include the IrDA
* port here since we have our own SIR/FIR driver (see drivers/net/irda)
*
* Note also that we support "console=ttySAx" 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.
*
* Note that NanoEngine UART3 becomes UART2, and UART2 is no longer
* used here.
*/
static void __init sa1100_init_ports(void)
{
static int first = 1;
int i;
if (!first)
return;
first = 0;
for (i = 0; i < NR_PORTS; i++) {
sa1100_ports[i].port.uartclk = 3686400;
sa1100_ports[i].port.ops = &sa1100_pops;
sa1100_ports[i].port.fifosize = 8;
sa1100_ports[i].port.line = i;
sa1100_ports[i].port.iotype = SERIAL_IO_MEM;
init_timer(&sa1100_ports[i].timer);
sa1100_ports[i].timer.function = sa1100_timeout;
sa1100_ports[i].timer.data = (unsigned long)&sa1100_ports[i];
}
/*
* make transmit lines outputs, so that when the port
* is closed, the output is in the MARK state.
*/
PPDR |= PPC_TXD1 | PPC_TXD3;
PPSR |= PPC_TXD1 | PPC_TXD3;
}
void __init sa1100_register_uart_fns(struct sa1100_port_fns *fns)
{
if (fns->get_mctrl)
sa1100_pops.get_mctrl = fns->get_mctrl;
if (fns->set_mctrl)
sa1100_pops.set_mctrl = fns->set_mctrl;
sa1100_pops.pm = fns->pm;
sa1100_pops.set_wake = fns->set_wake;
}
void __init sa1100_register_uart(int idx, int port)
{
if (idx >= NR_PORTS) {
printk(KERN_ERR "%s: bad index number %d\n", __FUNCTION__, idx);
return;
}
switch (port) {
case 1:
sa1100_ports[idx].port.membase = (void __iomem *)&Ser1UTCR0;
sa1100_ports[idx].port.mapbase = _Ser1UTCR0;
sa1100_ports[idx].port.irq = IRQ_Ser1UART;
sa1100_ports[idx].port.flags = ASYNC_BOOT_AUTOCONF;
break;
case 2:
sa1100_ports[idx].port.membase = (void __iomem *)&Ser2UTCR0;
sa1100_ports[idx].port.mapbase = _Ser2UTCR0;
sa1100_ports[idx].port.irq = IRQ_Ser2ICP;
sa1100_ports[idx].port.flags = ASYNC_BOOT_AUTOCONF;
break;
case 3:
sa1100_ports[idx].port.membase = (void __iomem *)&Ser3UTCR0;
sa1100_ports[idx].port.mapbase = _Ser3UTCR0;
sa1100_ports[idx].port.irq = IRQ_Ser3UART;
sa1100_ports[idx].port.flags = ASYNC_BOOT_AUTOCONF;
break;
default:
printk(KERN_ERR "%s: bad port number %d\n", __FUNCTION__, port);
}
}
#ifdef CONFIG_SERIAL_SA1100_CONSOLE
/*
* Interrupts are disabled on entering
*/
static void
sa1100_console_write(struct console *co, const char *s, unsigned int count)
{
struct sa1100_port *sport = &sa1100_ports[co->index];
unsigned int old_utcr3, status, i;
/*
* First, save UTCR3 and then disable interrupts
*/
old_utcr3 = UART_GET_UTCR3(sport);
UART_PUT_UTCR3(sport, (old_utcr3 & ~(UTCR3_RIE | UTCR3_TIE)) |
UTCR3_TXE);
/*
* Now, do each character
*/
for (i = 0; i < count; i++) {
do {
status = UART_GET_UTSR1(sport);
} while (!(status & UTSR1_TNF));
UART_PUT_CHAR(sport, s[i]);
if (s[i] == '\n') {
do {
status = UART_GET_UTSR1(sport);
} while (!(status & UTSR1_TNF));
UART_PUT_CHAR(sport, '\r');
}
}
/*
* Finally, wait for transmitter to become empty
* and restore UTCR3
*/
do {
status = UART_GET_UTSR1(sport);
} while (status & UTSR1_TBY);
UART_PUT_UTCR3(sport, old_utcr3);
}
/*
* If the port was already initialised (eg, by a boot loader),
* try to determine the current setup.
*/
static void __init
sa1100_console_get_options(struct sa1100_port *sport, int *baud,
int *parity, int *bits)
{
unsigned int utcr3;
utcr3 = UART_GET_UTCR3(sport) & (UTCR3_RXE | UTCR3_TXE);
if (utcr3 == (UTCR3_RXE | UTCR3_TXE)) {
/* ok, the port was enabled */
unsigned int utcr0, quot;
utcr0 = UART_GET_UTCR0(sport);
*parity = 'n';
if (utcr0 & UTCR0_PE) {
if (utcr0 & UTCR0_OES)
*parity = 'e';
else
*parity = 'o';
}
if (utcr0 & UTCR0_DSS)
*bits = 8;
else
*bits = 7;
quot = UART_GET_UTCR2(sport) | UART_GET_UTCR1(sport) << 8;
quot &= 0xfff;
*baud = sport->port.uartclk / (16 * (quot + 1));
}
}
static int __init
sa1100_console_setup(struct console *co, char *options)
{
struct sa1100_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 >= NR_PORTS)
co->index = 0;
sport = &sa1100_ports[co->index];
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
sa1100_console_get_options(sport, &baud, &parity, &bits);
return uart_set_options(&sport->port, co, baud, parity, bits, flow);
}
static struct uart_driver sa1100_reg;
static struct console sa1100_console = {
.name = "ttySA",
.write = sa1100_console_write,
.device = uart_console_device,
.setup = sa1100_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &sa1100_reg,
};
static int __init sa1100_rs_console_init(void)
{
sa1100_init_ports();
register_console(&sa1100_console);
return 0;
}
console_initcall(sa1100_rs_console_init);
#define SA1100_CONSOLE &sa1100_console
#else
#define SA1100_CONSOLE NULL
#endif
static struct uart_driver sa1100_reg = {
.owner = THIS_MODULE,
.driver_name = "ttySA",
.dev_name = "ttySA",
.devfs_name = "ttySA",
.major = SERIAL_SA1100_MAJOR,
.minor = MINOR_START,
.nr = NR_PORTS,
.cons = SA1100_CONSOLE,
};
static int sa1100_serial_suspend(struct platform_device *dev, pm_message_t state)
{
struct sa1100_port *sport = platform_get_drvdata(dev);
if (sport)
uart_suspend_port(&sa1100_reg, &sport->port);
return 0;
}
static int sa1100_serial_resume(struct platform_device *dev)
{
struct sa1100_port *sport = platform_get_drvdata(dev);
if (sport)
uart_resume_port(&sa1100_reg, &sport->port);
return 0;
}
static int sa1100_serial_probe(struct platform_device *dev)
{
struct resource *res = dev->resource;
int i;
for (i = 0; i < dev->num_resources; i++, res++)
if (res->flags & IORESOURCE_MEM)
break;
if (i < dev->num_resources) {
for (i = 0; i < NR_PORTS; i++) {
if (sa1100_ports[i].port.mapbase != res->start)
continue;
sa1100_ports[i].port.dev = &dev->dev;
uart_add_one_port(&sa1100_reg, &sa1100_ports[i].port);
platform_set_drvdata(dev, &sa1100_ports[i]);
break;
}
}
return 0;
}
static int sa1100_serial_remove(struct platform_device *pdev)
{
struct sa1100_port *sport = platform_get_drvdata(pdev);
platform_set_drvdata(pdev, NULL);
if (sport)
uart_remove_one_port(&sa1100_reg, &sport->port);
return 0;
}
static struct platform_driver sa11x0_serial_driver = {
.probe = sa1100_serial_probe,
.remove = sa1100_serial_remove,
.suspend = sa1100_serial_suspend,
.resume = sa1100_serial_resume,
.driver = {
.name = "sa11x0-uart",
},
};
static int __init sa1100_serial_init(void)
{
int ret;
printk(KERN_INFO "Serial: SA11x0 driver $Revision: 1.50 $\n");
sa1100_init_ports();
ret = uart_register_driver(&sa1100_reg);
if (ret == 0) {
ret = platform_driver_register(&sa11x0_serial_driver);
if (ret)
uart_unregister_driver(&sa1100_reg);
}
return ret;
}
static void __exit sa1100_serial_exit(void)
{
platform_driver_unregister(&sa11x0_serial_driver);
uart_unregister_driver(&sa1100_reg);
}
module_init(sa1100_serial_init);
module_exit(sa1100_serial_exit);
MODULE_AUTHOR("Deep Blue Solutions Ltd");
MODULE_DESCRIPTION("SA1100 generic serial port driver $Revision: 1.50 $");
MODULE_LICENSE("GPL");
MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_SA1100_MAJOR);
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