[RFC PATCH] watchdog: ep93xx: Use the WatchDog Timer Driver Core.

From: H Hartley Sweeten
Date: Mon Aug 01 2011 - 16:58:31 EST


Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Wim Van Sebroeck <wim@xxxxxxxxx> (maintainer:WATCHDOG DEVICE D...)

---

diff --git a/drivers/watchdog/ep93xx_wdt.c b/drivers/watchdog/ep93xx_wdt.c
index 726b7df..bb97351 100644
--- a/drivers/watchdog/ep93xx_wdt.c
+++ b/drivers/watchdog/ep93xx_wdt.c
@@ -24,11 +24,9 @@
*/

#include <linux/module.h>
-#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/timer.h>
-#include <linux/uaccess.h>
#include <linux/io.h>
#include <mach/hardware.h>

@@ -39,15 +37,17 @@
#define WDT_TIMEOUT 30

static int nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");
+
static int timeout = WDT_TIMEOUT;
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout,
+ "Watchdog timeout in seconds. (1<=timeout<=3600, default="
+ __MODULE_STRING(WDT_TIMEOUT) ")");

static struct timer_list timer;
static unsigned long next_heartbeat;
-static unsigned long wdt_status;
-static unsigned long boot_status;
-
-#define WDT_IN_USE 0
-#define WDT_OK_TO_CLOSE 1

#define EP93XX_WDT_REG(x) (EP93XX_WATCHDOG_BASE + (x))
#define EP93XX_WDT_WATCHDOG EP93XX_WDT_REG(0x00)
@@ -71,130 +71,46 @@ static inline void wdt_ping(void)
__raw_writew(0x5555, EP93XX_WDT_WATCHDOG);
}

-static void wdt_startup(void)
+static int void ep93xx_wdt_start(struct watchdog_device *wdd)
{
- next_heartbeat = jiffies + (timeout * HZ);
+ next_heartbeat = jiffies + (wdd->timeout * HZ);

wdt_enable();
mod_timer(&timer, jiffies + WDT_INTERVAL);
+ return 0;
}

-static void wdt_shutdown(void)
+static int ep93xx_wdt_stop(struct watchdog_device *wdd)
{
del_timer_sync(&timer);
wdt_disable();
+ return 0;
}

-static void wdt_keepalive(void)
+static int ep93xx_wdt_keepalive(struct watchdog_device *wdd)
{
/* user land ping */
- next_heartbeat = jiffies + (timeout * HZ);
-}
-
-static int ep93xx_wdt_open(struct inode *inode, struct file *file)
-{
- if (test_and_set_bit(WDT_IN_USE, &wdt_status))
- return -EBUSY;
-
- clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
-
- wdt_startup();
-
- return nonseekable_open(inode, file);
-}
-
-static ssize_t
-ep93xx_wdt_write(struct file *file, const char __user *data, size_t len,
- loff_t *ppos)
-{
- if (len) {
- if (!nowayout) {
- size_t i;
-
- clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
-
- for (i = 0; i != len; i++) {
- char c;
-
- if (get_user(c, data + i))
- return -EFAULT;
-
- if (c == 'V')
- set_bit(WDT_OK_TO_CLOSE, &wdt_status);
- else
- clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
- }
- }
- wdt_keepalive();
- }
-
- return len;
+ next_heartbeat = jiffies + (wdd->timeout * HZ);
+ return 0;
}

-static const struct watchdog_info ident = {
- .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE,
- .identity = "EP93xx Watchdog",
+static const struct watchdog_info ep93xx_wdt_ident = {
+ .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE,
+ .identity = "EP93xx Watchdog",
};

-static long ep93xx_wdt_ioctl(struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- int ret = -ENOTTY;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- ret = copy_to_user((struct watchdog_info __user *)arg, &ident,
- sizeof(ident)) ? -EFAULT : 0;
- break;
-
- case WDIOC_GETSTATUS:
- ret = put_user(0, (int __user *)arg);
- break;
-
- case WDIOC_GETBOOTSTATUS:
- ret = put_user(boot_status, (int __user *)arg);
- break;
-
- case WDIOC_KEEPALIVE:
- wdt_keepalive();
- ret = 0;
- break;
-
- case WDIOC_GETTIMEOUT:
- /* actually, it is 0.250 seconds.... */
- ret = put_user(1, (int __user *)arg);
- break;
- }
- return ret;
-}
-
-static int ep93xx_wdt_release(struct inode *inode, struct file *file)
-{
- if (test_bit(WDT_OK_TO_CLOSE, &wdt_status))
- wdt_shutdown();
- else
- printk(KERN_CRIT PFX
- "Device closed unexpectedly - timer will not stop\n");
-
- clear_bit(WDT_IN_USE, &wdt_status);
- clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
-
- return 0;
-}
-
-static const struct file_operations ep93xx_wdt_fops = {
+static const struct watchdog_ops ep93xx_wdt_ops = {
.owner = THIS_MODULE,
- .write = ep93xx_wdt_write,
- .unlocked_ioctl = ep93xx_wdt_ioctl,
- .open = ep93xx_wdt_open,
- .release = ep93xx_wdt_release,
- .llseek = no_llseek,
+ .start = ep93xx_wdt_start,
+ .stop = ep93xx_wdt_stop,
+ .ping = ep93xx_wdt_keepalive,
};

-static struct miscdevice ep93xx_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &ep93xx_wdt_fops,
+static struct watchdog_device ep93xx_wdd = {
+ .info = &ep93xx_wdt_ident,
+ .ops = &ep93xx_wdt_ops,
+ .min_timeout = 1,
+ .max_timeout = 3600,
};

static void ep93xx_timer_ping(unsigned long data)
@@ -210,43 +126,31 @@ static int __init ep93xx_wdt_init(void)
{
int err;

- err = misc_register(&ep93xx_wdt_miscdev);
+ ep93xx_wdd.bootstatus = readl(EP93XX_WDT_WATCHDOG);
+ ep93xx_wdd.timeout = timeout;
+
+ err = watchdog_register_device(&ep93xx_wdd);
+ if (err)
+ return err;

- boot_status = __raw_readl(EP93XX_WDT_WATCHDOG) & 0x01 ? 1 : 0;
+ setup_timer(&timer, ep93xx_timer_ping, 1);

printk(KERN_INFO PFX "EP93XX watchdog, driver version "
WDT_VERSION "%s\n",
- (__raw_readl(EP93XX_WDT_WATCHDOG) & 0x08)
+ (ep93xx_wdd.bootstatus & 0x08)
? " (nCS1 disable detected)" : "");

- if (timeout < 1 || timeout > 3600) {
- timeout = WDT_TIMEOUT;
- printk(KERN_INFO PFX
- "timeout value must be 1<=x<=3600, using %d\n",
- timeout);
- }
-
- setup_timer(&timer, ep93xx_timer_ping, 1);
- return err;
+ return 0;
}
+module_init(ep93xx_wdt_init);

static void __exit ep93xx_wdt_exit(void)
{
- wdt_shutdown();
- misc_deregister(&ep93xx_wdt_miscdev);
+ wdt_shutdown(&ep93xx_wdd);
+ watchdog_unregister_device(&ep93xx_wdd);
}
-
-module_init(ep93xx_wdt_init);
module_exit(ep93xx_wdt_exit);

-module_param(nowayout, int, 0);
-MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");
-
-module_param(timeout, int, 0);
-MODULE_PARM_DESC(timeout,
- "Watchdog timeout in seconds. (1<=timeout<=3600, default="
- __MODULE_STRING(WDT_TIMEOUT) ")");
-
MODULE_AUTHOR("Ray Lehtiniemi <rayl@xxxxxxxx>,"
"Alessandro Zummo <a.zummo@xxxxxxxxxxxx>");
MODULE_DESCRIPTION("EP93xx Watchdog");
--
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