arch/xtensa/platforms/iss/console.c - maze/linux - Git at Google

 /*
  * arch/xtensa/platform-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/slab.h>
 #include <linux/mm.h>
 #include <linux/major.h>
 #include <linux/param.h>
 #include <linux/serial.h>
 #include <linux/serialP.h>

 #include <asm/uaccess.h>
 #include <asm/irq.h>

 #include <asm/platform/simcall.h>

 #include <linux/tty.h>
 #include <linux/tty_flip.h>

 #ifdef SERIAL_INLINE
 #define _INLINE_ inline
 #endif

 #define SERIAL_MAX_NUM_LINES 1
 #define SERIAL_TIMER_VALUE (20 * HZ)

 static struct tty_driver *serial_driver;
 static struct timer_list serial_timer;

 static DEFINE_SPINLOCK(timer_lock);

 int errno;

 static int __simc (int a, int b, int c, int d, int e, int f) __attribute__((__noinline__));
 static int __simc (int a, int b, int c, int d, int e, int f)
 {
 	int ret;
 	__asm__ __volatile__ ("simcall\n"
 			"mov %0, a2\n"
 			"mov %1, a3\n" : "=a" (ret), "=a" (errno)
 			: : "a2", "a3");
 	return ret;
 }

 static char *serial_version = "0.1";
 static char *serial_name = "ISS serial driver";

 /*
  * 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 void rs_poll(unsigned long);

 static int rs_open(struct tty_struct *tty, struct file * filp)
 {
 	int line = tty->index;

 	if ((line < 0) || (line >= SERIAL_MAX_NUM_LINES))
 		return -ENODEV;

 	spin_lock(&timer_lock);

 	if (tty->count == 1) {
 		init_timer(&serial_timer);
 		serial_timer.data = (unsigned long) tty;
 		serial_timer.function = rs_poll;
 		mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
 	}
 	spin_unlock(&timer_lock);

 	return 0;
 }


 /*
  * ------------------------------------------------------------
  * iss_serial_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)
 {
 	spin_lock(&timer_lock);
 	if (tty->count == 1)
 		del_timer_sync(&serial_timer);
 	spin_unlock(&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 (SYS_write, 1, (unsigned long)buf, count, 0, 0);
 	return count;
 }

 static void rs_poll(unsigned long priv)
 {
 	struct tty_struct* tty = (struct tty_struct*) priv;

 	struct timeval tv = { .tv_sec = 0, .tv_usec = 0 };
 	int i = 0;
 	unsigned char c;

 	spin_lock(&timer_lock);

 	while (__simc(SYS_select_one, 0, XTISS_SELECT_ONE_READ, (int)&tv,0,0)){
 		__simc (SYS_read, 0, (unsigned long)&c, 1, 0, 0);
 		tty_insert_flip_char(tty, c, TTY_NORMAL);
 		i++;
 	}

 	if (i)
 		tty_flip_buffer_push(tty);


 	mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
 	spin_unlock(&timer_lock);
 }


 static void rs_put_char(struct tty_struct *tty, unsigned char ch)
 {
 	char buf[2];

 	if (!tty)
 		return;

 	buf[0] = ch;
 	buf[1] = '\0';		/* Is this NULL necessary? */
 	__simc (SYS_write, 1, (unsigned long) buf, 1, 0, 0);
 }

 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_read_proc(char *page, char **start, off_t off, int count,
 			int *eof, void *data)
 {
 	int len = 0;
 	off_t begin = 0;

 	len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version);
 	*eof = 1;

 	if (off >= len + begin)
 		return 0;

 	*start = page + (off - begin);
 	return ((count < begin + len - off) ? count : begin + len - off);
 }


 static 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,
 	.read_proc = rs_read_proc
 };

 int __init rs_init(void)
 {
 	serial_driver = alloc_tty_driver(1);

 	printk ("%s %s\n", serial_name, serial_version);

 	/* Initialize the tty_driver structure */

 	serial_driver->owner = THIS_MODULE;
 	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);

 	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)))
 		printk("ISS_SERIAL: failed to unregister serial driver (%d)\n",
 		       error);
 	put_tty_driver(serial_driver);
 }


 /* 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 (SYS_write, 1, (unsigned long)s,
 			count < len ? count : len,0,0);
 }

 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 */
	/*
	* arch/xtensa/platform-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/slab.h>
	#include <linux/mm.h>
	#include <linux/major.h>
	#include <linux/param.h>
	#include <linux/serial.h>
	#include <linux/serialP.h>

	#include <asm/uaccess.h>
	#include <asm/irq.h>

	#include <asm/platform/simcall.h>

	#include <linux/tty.h>
	#include <linux/tty_flip.h>

	#ifdef SERIAL_INLINE
	#define _INLINE_ inline
	#endif

	#define SERIAL_MAX_NUM_LINES 1
	#define SERIAL_TIMER_VALUE (20 * HZ)

	static struct tty_driver *serial_driver;
	static struct timer_list serial_timer;

	static DEFINE_SPINLOCK(timer_lock);

	int errno;

	static int __simc (int a, int b, int c, int d, int e, int f) __attribute__((__noinline__));
	static int __simc (int a, int b, int c, int d, int e, int f)
	{
	int ret;
	__asm__ __volatile__ ("simcall\n"
	"mov %0, a2\n"
	"mov %1, a3\n" : "=a" (ret), "=a" (errno)
	: : "a2", "a3");
	return ret;
	}

	static char *serial_version = "0.1";
	static char *serial_name = "ISS serial driver";

	/*
	* 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 void rs_poll(unsigned long);

	static int rs_open(struct tty_struct tty, struct file filp)
	{
	int line = tty->index;

	if ((line < 0) \|\| (line >= SERIAL_MAX_NUM_LINES))
	return -ENODEV;

	spin_lock(&timer_lock);

	if (tty->count == 1) {
	init_timer(&serial_timer);
	serial_timer.data = (unsigned long) tty;
	serial_timer.function = rs_poll;
	mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
	}
	spin_unlock(&timer_lock);

	return 0;
	}


	/*
	* ------------------------------------------------------------
	* iss_serial_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)
	{
	spin_lock(&timer_lock);
	if (tty->count == 1)
	del_timer_sync(&serial_timer);
	spin_unlock(&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 (SYS_write, 1, (unsigned long)buf, count, 0, 0);
	return count;
	}

	static void rs_poll(unsigned long priv)
	{
	struct tty_struct* tty = (struct tty_struct*) priv;

	struct timeval tv = { .tv_sec = 0, .tv_usec = 0 };
	int i = 0;
	unsigned char c;

	spin_lock(&timer_lock);

	while (__simc(SYS_select_one, 0, XTISS_SELECT_ONE_READ, (int)&tv,0,0)){
	__simc (SYS_read, 0, (unsigned long)&c, 1, 0, 0);
	tty_insert_flip_char(tty, c, TTY_NORMAL);
	i++;
	}

	if (i)
	tty_flip_buffer_push(tty);


	mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE);
	spin_unlock(&timer_lock);
	}


	static void rs_put_char(struct tty_struct *tty, unsigned char ch)
	{
	char buf[2];

	if (!tty)
	return;

	buf[0] = ch;
	buf[1] = '\0'; /* Is this NULL necessary? */
	__simc (SYS_write, 1, (unsigned long) buf, 1, 0, 0);
	}

	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_read_proc(char page, char *start, off_t off, int count,
	int eof, void data)
	{
	int len = 0;
	off_t begin = 0;

	len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version);
	*eof = 1;

	if (off >= len + begin)
	return 0;

	*start = page + (off - begin);
	return ((count < begin + len - off) ? count : begin + len - off);
	}


	static 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,
	.read_proc = rs_read_proc
	};

	int __init rs_init(void)
	{
	serial_driver = alloc_tty_driver(1);

	printk ("%s %s\n", serial_name, serial_version);

	/* Initialize the tty_driver structure */

	serial_driver->owner = THIS_MODULE;
	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);

	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)))
	printk("ISS_SERIAL: failed to unregister serial driver (%d)\n",
	error);
	put_tty_driver(serial_driver);
	}


	/* 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 (SYS_write, 1, (unsigned long)s,
	count < len ? count : len,0,0);
	}

	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 */