lisa/android_kernel_xiaomi_sm8350
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
49f680ea7b
android_kernel_xiaomi_sm8350/arch/ia64/hp/sim/simserial.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2 
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

1033 lines
25 KiB
C
Raw Blame History

/*
* Simulated Serial Driver (fake serial)
*
* This driver is mostly used for bringup purposes and will go away.
* It has a strong dependency on the system console. All outputs
* are rerouted to the same facility as the one used by printk which, in our
* case means sys_sim.c console (goes via the simulator). The code hereafter
* is completely leveraged from the serial.c driver.
*
* Copyright (C) 1999-2000, 2002-2003 Hewlett-Packard Co
* Stephane Eranian <eranian@hpl.hp.com>
* David Mosberger-Tang <davidm@hpl.hp.com>
*
* 02/04/00 D. Mosberger Merged in serial.c bug fixes in rs_close().
* 02/25/00 D. Mosberger Synced up with 2.3.99pre-5 version of serial.c.
* 07/30/02 D. Mosberger Replace sti()/cli() with explicit spinlocks & local irq masking
*/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/major.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/console.h>
#include <linux/module.h>
#include <linux/serial.h>
#include <linux/serialP.h>
#include <asm/irq.h>
#include <asm/hw_irq.h>
#include <asm/uaccess.h>
#ifdef CONFIG_KDB
# include <linux/kdb.h>
#endif
#undef SIMSERIAL_DEBUG /* define this to get some debug information */
#define KEYBOARD_INTR 3 /* must match with simulator! */
#define NR_PORTS 1 /* only one port for now */
#define SERIAL_INLINE 1
#ifdef SERIAL_INLINE
#define _INLINE_ inline
#endif
#define IRQ_T(info) ((info->flags & ASYNC_SHARE_IRQ) ? SA_SHIRQ : SA_INTERRUPT)
#define SSC_GETCHAR 21
extern long ia64_ssc (long, long, long, long, int);
extern void ia64_ssc_connect_irq (long intr, long irq);
static char *serial_name = "SimSerial driver";
static char *serial_version = "0.6";
/*
* This has been extracted from asm/serial.h. We need one eventually but
* I don't know exactly what we're going to put in it so just fake one
* for now.
*/
#define BASE_BAUD ( 1843200 / 16 )
#define STD_COM_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)
/*
* Most of the values here are meaningless to this particular driver.
* However some values must be preserved for the code (leveraged from serial.c
* to work correctly).
* port must not be 0
* type must not be UNKNOWN
* So I picked arbitrary (guess from where?) values instead
*/
static struct serial_state rs_table[NR_PORTS]={
/* UART CLK PORT IRQ FLAGS */
{ 0, BASE_BAUD, 0x3F8, 0, STD_COM_FLAGS,0,PORT_16550 } /* ttyS0 */
};
/*
* Just for the fun of it !
*/
static struct serial_uart_config uart_config[] = {
{ "unknown", 1, 0 },
{ "8250", 1, 0 },
{ "16450", 1, 0 },
{ "16550", 1, 0 },
{ "16550A", 16, UART_CLEAR_FIFO | UART_USE_FIFO },
{ "cirrus", 1, 0 },
{ "ST16650", 1, UART_CLEAR_FIFO | UART_STARTECH },
{ "ST16650V2", 32, UART_CLEAR_FIFO | UART_USE_FIFO |
UART_STARTECH },
{ "TI16750", 64, UART_CLEAR_FIFO | UART_USE_FIFO},
{ 0, 0}
};
struct tty_driver *hp_simserial_driver;
static struct async_struct *IRQ_ports[NR_IRQS];
static struct console *console;
static unsigned char *tmp_buf;
static DECLARE_MUTEX(tmp_buf_sem);
extern struct console *console_drivers; /* from kernel/printk.c */
/*
* ------------------------------------------------------------
* rs_stop() and rs_start()
*
* This routines are called before setting or resetting tty->stopped.
* They enable or disable transmitter interrupts, as necessary.
* ------------------------------------------------------------
*/
static void rs_stop(struct tty_struct *tty)
{
#ifdef SIMSERIAL_DEBUG
printk("rs_stop: tty->stopped=%d tty->hw_stopped=%d tty->flow_stopped=%d\n",
tty->stopped, tty->hw_stopped, tty->flow_stopped);
#endif
}
static void rs_start(struct tty_struct *tty)
{
#if SIMSERIAL_DEBUG
printk("rs_start: tty->stopped=%d tty->hw_stopped=%d tty->flow_stopped=%d\n",
tty->stopped, tty->hw_stopped, tty->flow_stopped);
#endif
}
static void receive_chars(struct tty_struct *tty, struct pt_regs *regs)
{
unsigned char ch;
static unsigned char seen_esc = 0;
while ( (ch = ia64_ssc(0, 0, 0, 0, SSC_GETCHAR)) ) {
if ( ch == 27 && seen_esc == 0 ) {
seen_esc = 1;
continue;
} else {
if ( seen_esc==1 && ch == 'O' ) {
seen_esc = 2;
continue;
} else if ( seen_esc == 2 ) {
if ( ch == 'P' ) show_state(); /* F1 key */
#ifdef CONFIG_KDB
if ( ch == 'S' )
kdb(KDB_REASON_KEYBOARD, 0, (kdb_eframe_t) regs);
#endif
seen_esc = 0;
continue;
}
}
seen_esc = 0;
if (tty->flip.count >= TTY_FLIPBUF_SIZE) break;
*tty->flip.char_buf_ptr = ch;
*tty->flip.flag_buf_ptr = 0;
tty->flip.flag_buf_ptr++;
tty->flip.char_buf_ptr++;
tty->flip.count++;
}
tty_flip_buffer_push(tty);
}
/*
* This is the serial driver's interrupt routine for a single port
*/
static irqreturn_t rs_interrupt_single(int irq, void *dev_id, struct pt_regs * regs)
{
struct async_struct * info;
/*
* I don't know exactly why they don't use the dev_id opaque data
* pointer instead of this extra lookup table
*/
info = IRQ_ports[irq];
if (!info || !info->tty) {
printk(KERN_INFO "simrs_interrupt_single: info|tty=0 info=%p problem\n", info);
return IRQ_NONE;
}
/*
* pretty simple in our case, because we only get interrupts
* on inbound traffic
*/
receive_chars(info->tty, regs);
return IRQ_HANDLED;
}
/*
* -------------------------------------------------------------------
* Here ends the serial interrupt routines.
* -------------------------------------------------------------------
*/
#if 0
/*
* not really used in our situation so keep them commented out for now
*/
static DECLARE_TASK_QUEUE(tq_serial); /* used to be at the top of the file */
static void do_serial_bh(void)
{
run_task_queue(&tq_serial);
printk(KERN_ERR "do_serial_bh: called\n");
}
#endif
static void do_softint(void *private_)
{
printk(KERN_ERR "simserial: do_softint called\n");
}
static void rs_put_char(struct tty_struct *tty, unsigned char ch)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
unsigned long flags;
if (!tty || !info->xmit.buf) return;
local_irq_save(flags);
if (CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE) == 0) {
local_irq_restore(flags);
return;
}
info->xmit.buf[info->xmit.head] = ch;
info->xmit.head = (info->xmit.head + 1) & (SERIAL_XMIT_SIZE-1);
local_irq_restore(flags);
}
static _INLINE_ void transmit_chars(struct async_struct *info, int *intr_done)
{
int count;
unsigned long flags;
local_irq_save(flags);
if (info->x_char) {
char c = info->x_char;
console->write(console, &c, 1);
info->state->icount.tx++;
info->x_char = 0;
goto out;
}
if (info->xmit.head == info->xmit.tail || info->tty->stopped || info->tty->hw_stopped) {
#ifdef SIMSERIAL_DEBUG
printk("transmit_chars: head=%d, tail=%d, stopped=%d\n",
info->xmit.head, info->xmit.tail, info->tty->stopped);
#endif
goto out;
}
/*
* We removed the loop and try to do it in to chunks. We need
* 2 operations maximum because it's a ring buffer.
*
* First from current to tail if possible.
* Then from the beginning of the buffer until necessary
*/
count = min(CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE),
SERIAL_XMIT_SIZE - info->xmit.tail);
console->write(console, info->xmit.buf+info->xmit.tail, count);
info->xmit.tail = (info->xmit.tail+count) & (SERIAL_XMIT_SIZE-1);
/*
* We have more at the beginning of the buffer
*/
count = CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
if (count) {
console->write(console, info->xmit.buf, count);
info->xmit.tail += count;
}
out:
local_irq_restore(flags);
}
static void rs_flush_chars(struct tty_struct *tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
if (info->xmit.head == info->xmit.tail || tty->stopped || tty->hw_stopped ||
!info->xmit.buf)
return;
transmit_chars(info, NULL);
}
static int rs_write(struct tty_struct * tty,
const unsigned char *buf, int count)
{
int c, ret = 0;
struct async_struct *info = (struct async_struct *)tty->driver_data;
unsigned long flags;
if (!tty || !info->xmit.buf || !tmp_buf) return 0;
local_irq_save(flags);
while (1) {
c = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
if (count < c)
c = count;
if (c <= 0) {
break;
}
memcpy(info->xmit.buf + info->xmit.head, buf, c);
info->xmit.head = ((info->xmit.head + c) &
(SERIAL_XMIT_SIZE-1));
buf += c;
count -= c;
ret += c;
}
local_irq_restore(flags);
/*
* Hey, we transmit directly from here in our case
*/
if (CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE)
&& !tty->stopped && !tty->hw_stopped) {
transmit_chars(info, NULL);
}
return ret;
}
static int rs_write_room(struct tty_struct *tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
}
static int rs_chars_in_buffer(struct tty_struct *tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
}
static void rs_flush_buffer(struct tty_struct *tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
unsigned long flags;
local_irq_save(flags);
info->xmit.head = info->xmit.tail = 0;
local_irq_restore(flags);
wake_up_interruptible(&tty->write_wait);
if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
tty->ldisc.write_wakeup)
(tty->ldisc.write_wakeup)(tty);
}
/*
* This function is used to send a high-priority XON/XOFF character to
* the device
*/
static void rs_send_xchar(struct tty_struct *tty, char ch)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
info->x_char = ch;
if (ch) {
/*
* I guess we could call console->write() directly but
* let's do that for now.
*/
transmit_chars(info, NULL);
}
}
/*
* ------------------------------------------------------------
* rs_throttle()
*
* This routine is called by the upper-layer tty layer to signal that
* incoming characters should be throttled.
* ------------------------------------------------------------
*/
static void rs_throttle(struct tty_struct * tty)
{
if (I_IXOFF(tty)) rs_send_xchar(tty, STOP_CHAR(tty));
printk(KERN_INFO "simrs_throttle called\n");
}
static void rs_unthrottle(struct tty_struct * tty)
{
struct async_struct *info = (struct async_struct *)tty->driver_data;
if (I_IXOFF(tty)) {
if (info->x_char)
info->x_char = 0;
else
rs_send_xchar(tty, START_CHAR(tty));
}
printk(KERN_INFO "simrs_unthrottle called\n");
}
/*
* rs_break() --- routine which turns the break handling on or off
*/
static void rs_break(struct tty_struct *tty, int break_state)
{
}
static int rs_ioctl(struct tty_struct *tty, struct file * file,
unsigned int cmd, unsigned long arg)
{
if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
(cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
(cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
if (tty->flags & (1 << TTY_IO_ERROR))
return -EIO;
}
switch (cmd) {
case TIOCMGET:
printk(KERN_INFO "rs_ioctl: TIOCMGET called\n");
return -EINVAL;
case TIOCMBIS:
case TIOCMBIC:
case TIOCMSET:
printk(KERN_INFO "rs_ioctl: TIOCMBIS/BIC/SET called\n");
return -EINVAL;
case TIOCGSERIAL:
printk(KERN_INFO "simrs_ioctl TIOCGSERIAL called\n");
return 0;
case TIOCSSERIAL:
printk(KERN_INFO "simrs_ioctl TIOCSSERIAL called\n");
return 0;
case TIOCSERCONFIG:
printk(KERN_INFO "rs_ioctl: TIOCSERCONFIG called\n");
return -EINVAL;
case TIOCSERGETLSR: /* Get line status register */
printk(KERN_INFO "rs_ioctl: TIOCSERGETLSR called\n");
return -EINVAL;
case TIOCSERGSTRUCT:
printk(KERN_INFO "rs_ioctl: TIOCSERGSTRUCT called\n");
#if 0
if (copy_to_user((struct async_struct *) arg,
info, sizeof(struct async_struct)))
return -EFAULT;
#endif
return 0;
/*
* Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
* - mask passed in arg for lines of interest
* (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
* Caller should use TIOCGICOUNT to see which one it was
*/
case TIOCMIWAIT:
printk(KERN_INFO "rs_ioctl: TIOCMIWAIT: called\n");
return 0;
/*
* Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
* Return: write counters to the user passed counter struct
* NB: both 1->0 and 0->1 transitions are counted except for
* RI where only 0->1 is counted.
*/
case TIOCGICOUNT:
printk(KERN_INFO "rs_ioctl: TIOCGICOUNT called\n");
return 0;
case TIOCSERGWILD:
case TIOCSERSWILD:
/* "setserial -W" is called in Debian boot */
printk (KERN_INFO "TIOCSER?WILD ioctl obsolete, ignored.\n");
return 0;
default:
return -ENOIOCTLCMD;
}
return 0;
}
#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
{
unsigned int cflag = tty->termios->c_cflag;
if ( (cflag == old_termios->c_cflag)
&& ( RELEVANT_IFLAG(tty->termios->c_iflag)
== RELEVANT_IFLAG(old_termios->c_iflag)))
return;
/* Handle turning off CRTSCTS */
if ((old_termios->c_cflag & CRTSCTS) &&
!(tty->termios->c_cflag & CRTSCTS)) {
tty->hw_stopped = 0;
rs_start(tty);
}
}
/*
* This routine will shutdown a serial port; interrupts are disabled, and
* DTR is dropped if the hangup on close termio flag is on.
*/
static void shutdown(struct async_struct * info)
{
unsigned long flags;
struct serial_state *state;
int retval;
if (!(info->flags & ASYNC_INITIALIZED)) return;
state = info->state;
#ifdef SIMSERIAL_DEBUG
printk("Shutting down serial port %d (irq %d)....", info->line,
state->irq);
#endif
local_irq_save(flags);
{
/*
* First unlink the serial port from the IRQ chain...
*/
if (info->next_port)
info->next_port->prev_port = info->prev_port;
if (info->prev_port)
info->prev_port->next_port = info->next_port;
else
IRQ_ports[state->irq] = info->next_port;
/*
* Free the IRQ, if necessary
*/
if (state->irq && (!IRQ_ports[state->irq] ||
!IRQ_ports[state->irq]->next_port)) {
if (IRQ_ports[state->irq]) {
free_irq(state->irq, NULL);
retval = request_irq(state->irq, rs_interrupt_single,
IRQ_T(info), "serial", NULL);
if (retval)
printk(KERN_ERR "serial shutdown: request_irq: error %d"
" Couldn't reacquire IRQ.\n", retval);
} else
free_irq(state->irq, NULL);
}
if (info->xmit.buf) {
free_page((unsigned long) info->xmit.buf);
info->xmit.buf = 0;
}
if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags);
info->flags &= ~ASYNC_INITIALIZED;
}
local_irq_restore(flags);
}
/*
* ------------------------------------------------------------
* rs_close()
*
* This routine is called when the serial port gets closed. First, we
* wait for the last remaining data to be sent. Then, we unlink its
* async structure from the interrupt chain if necessary, and we free
* that IRQ if nothing is left in the chain.
* ------------------------------------------------------------
*/
static void rs_close(struct tty_struct *tty, struct file * filp)
{
struct async_struct * info = (struct async_struct *)tty->driver_data;
struct serial_state *state;
unsigned long flags;
if (!info ) return;
state = info->state;
local_irq_save(flags);
if (tty_hung_up_p(filp)) {
#ifdef SIMSERIAL_DEBUG
printk("rs_close: hung_up\n");
#endif
local_irq_restore(flags);
return;
}
#ifdef SIMSERIAL_DEBUG
printk("rs_close ttys%d, count = %d\n", info->line, state->count);
#endif
if ((tty->count == 1) && (state->count != 1)) {
/*
* Uh, oh. tty->count is 1, which means that the tty
* structure will be freed. state->count should always
* be one in these conditions. If it's greater than
* one, we've got real problems, since it means the
* serial port won't be shutdown.
*/
printk(KERN_ERR "rs_close: bad serial port count; tty->count is 1, "
"state->count is %d\n", state->count);
state->count = 1;
}
if (--state->count < 0) {
printk(KERN_ERR "rs_close: bad serial port count for ttys%d: %d\n",
info->line, state->count);
state->count = 0;
}
if (state->count) {
local_irq_restore(flags);
return;
}
info->flags |= ASYNC_CLOSING;
local_irq_restore(flags);
/*
* Now we wait for the transmit buffer to clear; and we notify
* the line discipline to only process XON/XOFF characters.
*/
shutdown(info);
if (tty->driver->flush_buffer) tty->driver->flush_buffer(tty);
if (tty->ldisc.flush_buffer) tty->ldisc.flush_buffer(tty);
info->event = 0;
info->tty = 0;
if (info->blocked_open) {
if (info->close_delay) {
current->state = TASK_INTERRUPTIBLE;
schedule_timeout(info->close_delay);
}
wake_up_interruptible(&info->open_wait);
}
info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
wake_up_interruptible(&info->close_wait);
}
/*
* rs_wait_until_sent() --- wait until the transmitter is empty
*/
static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
{
}
/*
* rs_hangup() --- called by tty_hangup() when a hangup is signaled.
*/
static void rs_hangup(struct tty_struct *tty)
{
struct async_struct * info = (struct async_struct *)tty->driver_data;
struct serial_state *state = info->state;
#ifdef SIMSERIAL_DEBUG
printk("rs_hangup: called\n");
#endif
state = info->state;
rs_flush_buffer(tty);
if (info->flags & ASYNC_CLOSING)
return;
shutdown(info);
info->event = 0;
state->count = 0;
info->flags &= ~ASYNC_NORMAL_ACTIVE;
info->tty = 0;
wake_up_interruptible(&info->open_wait);
}
static int get_async_struct(int line, struct async_struct **ret_info)
{
struct async_struct *info;
struct serial_state *sstate;
sstate = rs_table + line;
sstate->count++;
if (sstate->info) {
*ret_info = sstate->info;
return 0;
}
info = kmalloc(sizeof(struct async_struct), GFP_KERNEL);
if (!info) {
sstate->count--;
return -ENOMEM;
}
memset(info, 0, sizeof(struct async_struct));
init_waitqueue_head(&info->open_wait);
init_waitqueue_head(&info->close_wait);
init_waitqueue_head(&info->delta_msr_wait);
info->magic = SERIAL_MAGIC;
info->port = sstate->port;
info->flags = sstate->flags;
info->xmit_fifo_size = sstate->xmit_fifo_size;
info->line = line;
INIT_WORK(&info->work, do_softint, info);
info->state = sstate;
if (sstate->info) {
kfree(info);
*ret_info = sstate->info;
return 0;
}
*ret_info = sstate->info = info;
return 0;
}
static int
startup(struct async_struct *info)
{
unsigned long flags;
int retval=0;
irqreturn_t (*handler)(int, void *, struct pt_regs *);
struct serial_state *state= info->state;
unsigned long page;
page = get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
local_irq_save(flags);
if (info->flags & ASYNC_INITIALIZED) {
free_page(page);
goto errout;
}
if (!state->port || !state->type) {
if (info->tty) set_bit(TTY_IO_ERROR, &info->tty->flags);
free_page(page);
goto errout;
}
if (info->xmit.buf)
free_page(page);
else
info->xmit.buf = (unsigned char *) page;
#ifdef SIMSERIAL_DEBUG
printk("startup: ttys%d (irq %d)...", info->line, state->irq);
#endif
/*
* Allocate the IRQ if necessary
*/
if (state->irq && (!IRQ_ports[state->irq] ||
!IRQ_ports[state->irq]->next_port)) {
if (IRQ_ports[state->irq]) {
retval = -EBUSY;
goto errout;
} else
handler = rs_interrupt_single;
retval = request_irq(state->irq, handler, IRQ_T(info), "simserial", NULL);
if (retval) {
if (capable(CAP_SYS_ADMIN)) {
if (info->tty)
set_bit(TTY_IO_ERROR,
&info->tty->flags);
retval = 0;
}
goto errout;
}
}
/*
* Insert serial port into IRQ chain.
*/
info->prev_port = 0;
info->next_port = IRQ_ports[state->irq];
if (info->next_port)
info->next_port->prev_port = info;
IRQ_ports[state->irq] = info;
if (info->tty) clear_bit(TTY_IO_ERROR, &info->tty->flags);
info->xmit.head = info->xmit.tail = 0;
#if 0
/*
* Set up serial timers...
*/
timer_table[RS_TIMER].expires = jiffies + 2*HZ/100;
timer_active |= 1 << RS_TIMER;
#endif
/*
* Set up the tty->alt_speed kludge
*/
if (info->tty) {
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
info->tty->alt_speed = 57600;
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
info->tty->alt_speed = 115200;
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
info->tty->alt_speed = 230400;
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
info->tty->alt_speed = 460800;
}
info->flags |= ASYNC_INITIALIZED;
local_irq_restore(flags);
return 0;
errout:
local_irq_restore(flags);
return retval;
}
/*
* This routine is called whenever a serial port is opened. It
* enables interrupts for a serial port, linking in its async structure into
* the IRQ chain. It also performs the serial-specific
* initialization for the tty structure.
*/
static int rs_open(struct tty_struct *tty, struct file * filp)
{
struct async_struct *info;
int retval, line;
unsigned long page;
line = tty->index;
if ((line < 0) || (line >= NR_PORTS))
return -ENODEV;
retval = get_async_struct(line, &info);
if (retval)
return retval;
tty->driver_data = info;
info->tty = tty;
#ifdef SIMSERIAL_DEBUG
printk("rs_open %s, count = %d\n", tty->name, info->state->count);
#endif
info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
if (!tmp_buf) {
page = get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
if (tmp_buf)
free_page(page);
else
tmp_buf = (unsigned char *) page;
}
/*
* If the port is the middle of closing, bail out now
*/
if (tty_hung_up_p(filp) ||
(info->flags & ASYNC_CLOSING)) {
if (info->flags & ASYNC_CLOSING)
interruptible_sleep_on(&info->close_wait);
#ifdef SERIAL_DO_RESTART
return ((info->flags & ASYNC_HUP_NOTIFY) ?
-EAGAIN : -ERESTARTSYS);
#else
return -EAGAIN;
#endif
}
/*
* Start up serial port
*/
retval = startup(info);
if (retval) {
return retval;
}
/*
* figure out which console to use (should be one already)
*/
console = console_drivers;
while (console) {
if ((console->flags & CON_ENABLED) && console->write) break;
console = console->next;
}
#ifdef SIMSERIAL_DEBUG
printk("rs_open ttys%d successful\n", info->line);
#endif
return 0;
}
/*
* /proc fs routines....
*/
static inline int line_info(char *buf, struct serial_state *state)
{
return sprintf(buf, "%d: uart:%s port:%lX irq:%d\n",
state->line, uart_config[state->type].name,
state->port, state->irq);
}
static int rs_read_proc(char *page, char **start, off_t off, int count,
int *eof, void *data)
{
int i, len = 0, l;
off_t begin = 0;
len += sprintf(page, "simserinfo:1.0 driver:%s\n", serial_version);
for (i = 0; i < NR_PORTS && len < 4000; i++) {
l = line_info(page + len, &rs_table[i]);
len += l;
if (len+begin > off+count)
goto done;
if (len+begin < off) {
begin += len;
len = 0;
}
}
*eof = 1;
done:
if (off >= len+begin)
return 0;
*start = page + (begin-off);
return ((count < begin+len-off) ? count : begin+len-off);
}
/*
* ---------------------------------------------------------------------
* rs_init() and friends
*
* rs_init() is called at boot-time to initialize the serial driver.
* ---------------------------------------------------------------------
*/
/*
* This routine prints out the appropriate serial driver version
* number, and identifies which options were configured into this
* driver.
*/
static inline void show_serial_version(void)
{
printk(KERN_INFO "%s version %s with", serial_name, serial_version);
printk(KERN_INFO " no serial options enabled\n");
}
static struct tty_operations hp_ops = {
.open = rs_open,
.close = rs_close,
.write = rs_write,
.put_char = rs_put_char,
.flush_chars = rs_flush_chars,
.write_room = rs_write_room,
.chars_in_buffer = rs_chars_in_buffer,
.flush_buffer = rs_flush_buffer,
.ioctl = rs_ioctl,
.throttle = rs_throttle,
.unthrottle = rs_unthrottle,
.send_xchar = rs_send_xchar,
.set_termios = rs_set_termios,
.stop = rs_stop,
.start = rs_start,
.hangup = rs_hangup,
.break_ctl = rs_break,
.wait_until_sent = rs_wait_until_sent,
.read_proc = rs_read_proc,
};
/*
* The serial driver boot-time initialization code!
*/
static int __init
simrs_init (void)
{
int i;
struct serial_state *state;
if (!ia64_platform_is("hpsim"))
return -ENODEV;
hp_simserial_driver = alloc_tty_driver(1);
if (!hp_simserial_driver)
return -ENOMEM;
show_serial_version();
/* Initialize the tty_driver structure */
hp_simserial_driver->owner = THIS_MODULE;
hp_simserial_driver->driver_name = "simserial";
hp_simserial_driver->name = "ttyS";
hp_simserial_driver->major = TTY_MAJOR;
hp_simserial_driver->minor_start = 64;
hp_simserial_driver->type = TTY_DRIVER_TYPE_SERIAL;
hp_simserial_driver->subtype = SERIAL_TYPE_NORMAL;
hp_simserial_driver->init_termios = tty_std_termios;
hp_simserial_driver->init_termios.c_cflag =
B9600 | CS8 | CREAD | HUPCL | CLOCAL;
hp_simserial_driver->flags = TTY_DRIVER_REAL_RAW;
tty_set_operations(hp_simserial_driver, &hp_ops);
/*
* Let's have a little bit of fun !
*/
for (i = 0, state = rs_table; i < NR_PORTS; i++,state++) {
if (state->type == PORT_UNKNOWN) continue;
if (!state->irq) {
state->irq = assign_irq_vector(AUTO_ASSIGN);
ia64_ssc_connect_irq(KEYBOARD_INTR, state->irq);
}
printk(KERN_INFO "ttyS%d at 0x%04lx (irq = %d) is a %s\n",
state->line,
state->port, state->irq,
uart_config[state->type].name);
}
if (tty_register_driver(hp_simserial_driver))
panic("Couldn't register simserial driver\n");
return 0;
}
#ifndef MODULE
__initcall(simrs_init);
#endif
Reference in New Issue View Git Blame Copy Permalink