kernel-ark/drivers/watchdog/mtx-1_wdt.c
Manuel Lauss b7f720d68c MIPS: Alchemy: Clean up GPIO registers and accessors
remove au_readl/au_writel, remove the predefined GPIO1/2 KSEG1 register
addresses and fix the fallout in all boards and drivers.

This also fixes a bug in the mtx-1_wdt driver which was introduced by
commit 6ea8115bb6
("Convert mtx1 wdt to be a platform device and use generic GPIO API")
before this patch mtx-1_wdt only modified GPIO215, the patch then
used the gpio resource information as bit index into the GPIO2 register
but the conversion to the GPIO API didn't realize that.
With this patch the drivers original behaviour is restored and GPIO15
is left alone.

Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
Cc: Florian Fainelli <florian@openwrt.org>
To: Linux-MIPS <linux-mips@linux-mips.org>
Cc: linux-watchdog@vger.kernel.org
Cc: Wim Van Sebroeck <wim@iguana.be>
Patchwork: https://patchwork.linux-mips.org/patch/2381/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org
2011-05-19 09:55:46 +01:00

271 lines
6.4 KiB
C

/*
* Driver for the MTX-1 Watchdog.
*
* (C) Copyright 2005 4G Systems <info@4g-systems.biz>,
* All Rights Reserved.
* http://www.4g-systems.biz
*
* (C) Copyright 2007 OpenWrt.org, Florian Fainelli <florian@openwrt.org>
*
* 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.
*
* Neither Michael Stickel nor 4G Systems admit liability nor provide
* warranty for any of this software. This material is provided
* "AS-IS" and at no charge.
*
* (c) Copyright 2005 4G Systems <info@4g-systems.biz>
*
* Release 0.01.
* Author: Michael Stickel michael.stickel@4g-systems.biz
*
* Release 0.02.
* Author: Florian Fainelli florian@openwrt.org
* use the Linux watchdog/timer APIs
*
* The Watchdog is configured to reset the MTX-1
* if it is not triggered for 100 seconds.
* It should not be triggered more often than 1.6 seconds.
*
* A timer triggers the watchdog every 5 seconds, until
* it is opened for the first time. After the first open
* it MUST be triggered every 2..95 seconds.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/timer.h>
#include <linux/completion.h>
#include <linux/jiffies.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#include <linux/gpio.h>
#include <asm/mach-au1x00/au1000.h>
#define MTX1_WDT_INTERVAL (5 * HZ)
static int ticks = 100 * HZ;
static struct {
struct completion stop;
spinlock_t lock;
int running;
struct timer_list timer;
int queue;
int default_ticks;
unsigned long inuse;
unsigned gpio;
int gstate;
} mtx1_wdt_device;
static void mtx1_wdt_trigger(unsigned long unused)
{
u32 tmp;
spin_lock(&mtx1_wdt_device.lock);
if (mtx1_wdt_device.running)
ticks--;
/* toggle wdt gpio */
mtx1_wdt_device.gstate = ~mtx1_wdt_device.gstate;
if (mtx1_wdt_device.gstate)
gpio_direction_output(mtx1_wdt_device.gpio, 1);
else
gpio_direction_input(mtx1_wdt_device.gpio);
if (mtx1_wdt_device.queue && ticks)
mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
else
complete(&mtx1_wdt_device.stop);
spin_unlock(&mtx1_wdt_device.lock);
}
static void mtx1_wdt_reset(void)
{
ticks = mtx1_wdt_device.default_ticks;
}
static void mtx1_wdt_start(void)
{
unsigned long flags;
spin_lock_irqsave(&mtx1_wdt_device.lock, flags);
if (!mtx1_wdt_device.queue) {
mtx1_wdt_device.queue = 1;
mtx1_wdt_device.gstate = 1;
gpio_direction_output(mtx1_wdt_device.gpio, 1);
mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
}
mtx1_wdt_device.running++;
spin_unlock_irqrestore(&mtx1_wdt_device.lock, flags);
}
static int mtx1_wdt_stop(void)
{
unsigned long flags;
spin_lock_irqsave(&mtx1_wdt_device.lock, flags);
if (mtx1_wdt_device.queue) {
mtx1_wdt_device.queue = 0;
mtx1_wdt_device.gstate = 0;
gpio_direction_output(mtx1_wdt_device.gpio, 0);
}
ticks = mtx1_wdt_device.default_ticks;
spin_unlock_irqrestore(&mtx1_wdt_device.lock, flags);
return 0;
}
/* Filesystem functions */
static int mtx1_wdt_open(struct inode *inode, struct file *file)
{
if (test_and_set_bit(0, &mtx1_wdt_device.inuse))
return -EBUSY;
return nonseekable_open(inode, file);
}
static int mtx1_wdt_release(struct inode *inode, struct file *file)
{
clear_bit(0, &mtx1_wdt_device.inuse);
return 0;
}
static long mtx1_wdt_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
void __user *argp = (void __user *)arg;
int __user *p = (int __user *)argp;
unsigned int value;
static const struct watchdog_info ident = {
.options = WDIOF_CARDRESET,
.identity = "MTX-1 WDT",
};
switch (cmd) {
case WDIOC_GETSUPPORT:
if (copy_to_user(argp, &ident, sizeof(ident)))
return -EFAULT;
break;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
put_user(0, p);
break;
case WDIOC_SETOPTIONS:
if (get_user(value, p))
return -EFAULT;
if (value & WDIOS_ENABLECARD)
mtx1_wdt_start();
else if (value & WDIOS_DISABLECARD)
mtx1_wdt_stop();
else
return -EINVAL;
return 0;
case WDIOC_KEEPALIVE:
mtx1_wdt_reset();
break;
default:
return -ENOTTY;
}
return 0;
}
static ssize_t mtx1_wdt_write(struct file *file, const char *buf,
size_t count, loff_t *ppos)
{
if (!count)
return -EIO;
mtx1_wdt_reset();
return count;
}
static const struct file_operations mtx1_wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.unlocked_ioctl = mtx1_wdt_ioctl,
.open = mtx1_wdt_open,
.write = mtx1_wdt_write,
.release = mtx1_wdt_release,
};
static struct miscdevice mtx1_wdt_misc = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &mtx1_wdt_fops,
};
static int __devinit mtx1_wdt_probe(struct platform_device *pdev)
{
int ret;
mtx1_wdt_device.gpio = pdev->resource[0].start;
spin_lock_init(&mtx1_wdt_device.lock);
init_completion(&mtx1_wdt_device.stop);
mtx1_wdt_device.queue = 0;
clear_bit(0, &mtx1_wdt_device.inuse);
setup_timer(&mtx1_wdt_device.timer, mtx1_wdt_trigger, 0L);
mtx1_wdt_device.default_ticks = ticks;
ret = misc_register(&mtx1_wdt_misc);
if (ret < 0) {
printk(KERN_ERR " mtx-1_wdt : failed to register\n");
return ret;
}
mtx1_wdt_start();
printk(KERN_INFO "MTX-1 Watchdog driver\n");
return 0;
}
static int __devexit mtx1_wdt_remove(struct platform_device *pdev)
{
/* FIXME: do we need to lock this test ? */
if (mtx1_wdt_device.queue) {
mtx1_wdt_device.queue = 0;
wait_for_completion(&mtx1_wdt_device.stop);
}
misc_deregister(&mtx1_wdt_misc);
return 0;
}
static struct platform_driver mtx1_wdt = {
.probe = mtx1_wdt_probe,
.remove = __devexit_p(mtx1_wdt_remove),
.driver.name = "mtx1-wdt",
.driver.owner = THIS_MODULE,
};
static int __init mtx1_wdt_init(void)
{
return platform_driver_register(&mtx1_wdt);
}
static void __exit mtx1_wdt_exit(void)
{
platform_driver_unregister(&mtx1_wdt);
}
module_init(mtx1_wdt_init);
module_exit(mtx1_wdt_exit);
MODULE_AUTHOR("Michael Stickel, Florian Fainelli");
MODULE_DESCRIPTION("Driver for the MTX-1 watchdog");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS("platform:mtx1-wdt");