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/*
* arch/xtensa/platforms/iss/console.c
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001-2005 Tensilica Inc.
* Authors Christian Zankel, Joe Taylor
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/console.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/major.h>
#include <linux/param.h>
#include <linux/seq_file.h>
#include <linux/serial.h>
#include <linux/uaccess.h>
#include <asm/irq.h>
#include <platform/simcall.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#define SERIAL_MAX_NUM_LINES 1
#define SERIAL_TIMER_VALUE (HZ / 10)
static void rs_poll(struct timer_list *);
static struct tty_driver *serial_driver;
static struct tty_port serial_port;
static DEFINE_TIMER(serial_timer, rs_poll);
static DEFINE_SPINLOCK(timer_lock);
static int rs_open(struct tty_struct *tty, struct file * filp)
{
spin_lock_bh(&timer_lock);
if (tty->count == 1)
mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
spin_unlock_bh(&timer_lock);
return 0;
}
static void rs_close(struct tty_struct *tty, struct file * filp)
{
spin_lock_bh(&timer_lock);
if (tty->count == 1)
del_timer_sync(&serial_timer);
spin_unlock_bh(&timer_lock);
}
static int rs_write(struct tty_struct * tty,
const unsigned char *buf, int count)
{
/* see drivers/char/serialX.c to reference original version */
simc_write(1, buf, count);
return count;
}
static void rs_poll(struct timer_list *unused)
{
struct tty_port *port = &serial_port;
int i = 0;
int rd = 1;
unsigned char c;
spin_lock(&timer_lock);
while (simc_poll(0)) {
rd = simc_read(0, &c, 1);
if (rd <= 0)
break;
tty_insert_flip_char(port, c, TTY_NORMAL);
i++;
}
if (i)
tty_flip_buffer_push(port);
if (rd)
mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
spin_unlock(&timer_lock);
}
static int rs_put_char(struct tty_struct *tty, unsigned char ch)
{
return rs_write(tty, &ch, 1);
}
static void rs_flush_chars(struct tty_struct *tty)
{
}
static int rs_write_room(struct tty_struct *tty)
{
/* Let's say iss can always accept 2K characters.. */
return 2 * 1024;
}
static int rs_chars_in_buffer(struct tty_struct *tty)
{
/* the iss doesn't buffer characters */
return 0;
}
static void rs_hangup(struct tty_struct *tty)
{
/* Stub, once again.. */
}
static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
{
/* Stub, once again.. */
}
static int rs_proc_show(struct seq_file *m, void *v)
{
seq_printf(m, "serinfo:1.0 driver:0.1\n");
return 0;
}
static const struct tty_operations serial_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,
.hangup = rs_hangup,
.wait_until_sent = rs_wait_until_sent,
.proc_show = rs_proc_show,
};
int __init rs_init(void)
{
tty_port_init(&serial_port);
serial_driver = alloc_tty_driver(SERIAL_MAX_NUM_LINES);
/* Initialize the tty_driver structure */
serial_driver->driver_name = "iss_serial";
serial_driver->name = "ttyS";
serial_driver->major = TTY_MAJOR;
serial_driver->minor_start = 64;
serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
serial_driver->subtype = SERIAL_TYPE_NORMAL;
serial_driver->init_termios = tty_std_termios;
serial_driver->init_termios.c_cflag =
B9600 | CS8 | CREAD | HUPCL | CLOCAL;
serial_driver->flags = TTY_DRIVER_REAL_RAW;
tty_set_operations(serial_driver, &serial_ops);
tty_port_link_device(&serial_port, serial_driver, 0);
if (tty_register_driver(serial_driver))
panic("Couldn't register serial driver\n");
return 0;
}
static __exit void rs_exit(void)
{
int error;
if ((error = tty_unregister_driver(serial_driver)))
pr_err("ISS_SERIAL: failed to unregister serial driver (%d)\n",
error);
put_tty_driver(serial_driver);
tty_port_destroy(&serial_port);
}
/* We use `late_initcall' instead of just `__initcall' as a workaround for
* the fact that (1) simcons_tty_init can't be called before tty_init,
* (2) tty_init is called via `module_init', (3) if statically linked,
* module_init == device_init, and (4) there's no ordering of init lists.
* We can do this easily because simcons is always statically linked, but
* other tty drivers that depend on tty_init and which must use
* `module_init' to declare their init routines are likely to be broken.
*/
late_initcall(rs_init);
#ifdef CONFIG_SERIAL_CONSOLE
static void iss_console_write(struct console *co, const char *s, unsigned count)
{
int len = strlen(s);
if (s != 0 && *s != 0)
simc_write(1, s, count < len ? count : len);
}
static struct tty_driver* iss_console_device(struct console *c, int *index)
{
*index = c->index;
return serial_driver;
}
static struct console sercons = {
.name = "ttyS",
.write = iss_console_write,
.device = iss_console_device,
.flags = CON_PRINTBUFFER,
.index = -1
};
static int __init iss_console_init(void)
{
register_console(&sercons);
return 0;
}
console_initcall(iss_console_init);
#endif /* CONFIG_SERIAL_CONSOLE */
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