watchdog: softdog: convert to watchdog core

Convert softdog.c to the new watchdog API.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

2 files changed, 37 insertions, 146 deletions

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 8f5c31763286..af7444188f5c 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -55,6 +55,7 @@ comment "Watchdog Device Drivers"
 
 config SOFT_WATCHDOG
         tristate "Software watchdog"
+        select WATCHDOG_CORE
         help
           A software monitoring watchdog. This will fail to reboot your system
           from some situations that the hardware watchdog will recover
diff --git a/drivers/watchdog/softdog.c b/drivers/watchdog/softdog.c
index da8620f829b2..fe83beb8f1b7 100644
--- a/drivers/watchdog/softdog.c
+++ b/drivers/watchdog/softdog.c
@@ -1,5 +1,5 @@
 /*
- *      SoftDog 0.07:   A Software Watchdog Device
+ *      SoftDog:        A Software Watchdog Device
  *
  *      (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>,
  *                                                      All Rights Reserved.
@@ -44,17 +44,15 @@
 #include <linux/timer.h>
 #include <linux/miscdevice.h>
 #include <linux/watchdog.h>
-#include <linux/fs.h>
 #include <linux/notifier.h>
 #include <linux/reboot.h>
 #include <linux/init.h>
 #include <linux/jiffies.h>
-#include <linux/uaccess.h>
 #include <linux/kernel.h>
 
 #define TIMER_MARGIN    60              /* Default is 60 seconds */
-static int soft_margin = TIMER_MARGIN;  /* in seconds */
-module_param(soft_margin, int, 0);
+static unsigned int soft_margin = TIMER_MARGIN; /* in seconds */
+module_param(soft_margin, uint, 0);
 MODULE_PARM_DESC(soft_margin,
         "Watchdog soft_margin in seconds. (0 < soft_margin < 65536, default="
                                         __MODULE_STRING(TIMER_MARGIN) ")");
@@ -65,16 +63,10 @@ MODULE_PARM_DESC(nowayout,
                 "Watchdog cannot be stopped once started (default="
                                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
-#ifdef ONLY_TESTING
-static int soft_noboot = 1;
-#else
 static int soft_noboot = 0;
-#endif  /* ONLY_TESTING */
-
 module_param(soft_noboot, int, 0);
 MODULE_PARM_DESC(soft_noboot,
-        "Softdog action, set to 1 to ignore reboots, 0 to reboot "
-                                        "(default depends on ONLY_TESTING)");
+        "Softdog action, set to 1 to ignore reboots, 0 to reboot (default=0)");
 
 static int soft_panic;
 module_param(soft_panic, int, 0);
@@ -89,9 +81,6 @@ static void watchdog_fire(unsigned long);
 
 static struct timer_list watchdog_ticktock =
                 TIMER_INITIALIZER(watchdog_fire, 0, 0);
-static unsigned long driver_open, orphan_timer;
-static char expect_close;
-
 
 /*
  *      If the timer expires..
@@ -99,9 +88,6 @@ static char expect_close;
 
 static void watchdog_fire(unsigned long data)
 {
-        if (test_and_clear_bit(0, &orphan_timer))
-                module_put(THIS_MODULE);
-
         if (soft_noboot)
                 pr_crit("Triggered - Reboot ignored\n");
         else if (soft_panic) {
@@ -118,127 +104,25 @@ static void watchdog_fire(unsigned long data)
  *      Softdog operations
  */
 
-static int softdog_keepalive(void)
+static int softdog_ping(struct watchdog_device *w)
 {
-        mod_timer(&watchdog_ticktock, jiffies+(soft_margin*HZ));
+        mod_timer(&watchdog_ticktock, jiffies+(w->timeout*HZ));
         return 0;
 }
 
-static int softdog_stop(void)
+static int softdog_stop(struct watchdog_device *w)
 {
         del_timer(&watchdog_ticktock);
         return 0;
 }
 
-static int softdog_set_heartbeat(int t)
+static int softdog_set_timeout(struct watchdog_device *w, unsigned int t)
 {
-        if ((t < 0x0001) || (t > 0xFFFF))
-                return -EINVAL;
-
-        soft_margin = t;
+        w->timeout = t;
         return 0;
 }
 
 /*
- *      /dev/watchdog handling
- */
-
-static int softdog_open(struct inode *inode, struct file *file)
-{
-        if (test_and_set_bit(0, &driver_open))
-                return -EBUSY;
-        if (!test_and_clear_bit(0, &orphan_timer))
-                __module_get(THIS_MODULE);
-        /*
-         *      Activate timer
-         */
-        softdog_keepalive();
-        return nonseekable_open(inode, file);
-}
-
-static int softdog_release(struct inode *inode, struct file *file)
-{
-        /*
-         *      Shut off the timer.
-         *      Lock it in if it's a module and we set nowayout
-         */
-        if (expect_close == 42) {
-                softdog_stop();
-                module_put(THIS_MODULE);
-        } else {
-                pr_crit("Unexpected close, not stopping watchdog!\n");
-                set_bit(0, &orphan_timer);
-                softdog_keepalive();
-        }
-        clear_bit(0, &driver_open);
-        expect_close = 0;
-        return 0;
-}
-
-static ssize_t softdog_write(struct file *file, const char __user *data,
-                                                size_t len, loff_t *ppos)
-{
-        /*
-         *      Refresh the timer.
-         */
-        if (len) {
-                if (!nowayout) {
-                        size_t i;
-
-                        /* In case it was set long ago */
-                        expect_close = 0;
-
-                        for (i = 0; i != len; i++) {
-                                char c;
-
-                                if (get_user(c, data + i))
-                                        return -EFAULT;
-                                if (c == 'V')
-                                        expect_close = 42;
-                        }
-                }
-                softdog_keepalive();
-        }
-        return len;
-}
-
-static long softdog_ioctl(struct file *file, unsigned int cmd,
-                                                        unsigned long arg)
-{
-        void __user *argp = (void __user *)arg;
-        int __user *p = argp;
-        int new_margin;
-        static const struct watchdog_info ident = {
-                .options =              WDIOF_SETTIMEOUT |
-                                        WDIOF_KEEPALIVEPING |
-                                        WDIOF_MAGICCLOSE,
-                .firmware_version =     0,
-                .identity =             "Software Watchdog",
-        };
-        switch (cmd) {
-        case WDIOC_GETSUPPORT:
-                return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
-        case WDIOC_GETSTATUS:
-        case WDIOC_GETBOOTSTATUS:
-                return put_user(0, p);
-        case WDIOC_KEEPALIVE:
-                softdog_keepalive();
-                return 0;
-        case WDIOC_SETTIMEOUT:
-                if (get_user(new_margin, p))
-                        return -EFAULT;
-                if (softdog_set_heartbeat(new_margin))
-                        return -EINVAL;
-                softdog_keepalive();
-                /* Fall */
-        case WDIOC_GETTIMEOUT:
-                return put_user(soft_margin, p);
-        default:
-                return -ENOTTY;
-        }
-}
-
-/*
  *      Notifier for system down
  */
 
@@ -247,7 +131,7 @@ static int softdog_notify_sys(struct notifier_block *this, unsigned long code,
 {
         if (code == SYS_DOWN || code == SYS_HALT)
                 /* Turn the WDT off */
-                softdog_stop();
+                softdog_stop(NULL);
         return NOTIFY_DONE;
 }
 
@@ -255,23 +139,28 @@ static int softdog_notify_sys(struct notifier_block *this, unsigned long code,
  *      Kernel Interfaces
  */
 
-static const struct file_operations softdog_fops = {
-        .owner          = THIS_MODULE,
-        .llseek         = no_llseek,
-        .write          = softdog_write,
-        .unlocked_ioctl = softdog_ioctl,
-        .open           = softdog_open,
-        .release        = softdog_release,
+static struct notifier_block softdog_notifier = {
+        .notifier_call  = softdog_notify_sys,
 };
 
-static struct miscdevice softdog_miscdev = {
-        .minor          = WATCHDOG_MINOR,
-        .name           = "watchdog",
-        .fops           = &softdog_fops,
+static struct watchdog_info softdog_info = {
+        .identity = "Software Watchdog",
+        .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
 };
 
-static struct notifier_block softdog_notifier = {
-        .notifier_call  = softdog_notify_sys,
+static struct watchdog_ops softdog_ops = {
+        .owner = THIS_MODULE,
+        .start = softdog_ping,
+        .stop = softdog_stop,
+        .ping = softdog_ping,
+        .set_timeout = softdog_set_timeout,
+};
+
+static struct watchdog_device softdog_dev = {
+        .info = &softdog_info,
+        .ops = &softdog_ops,
+        .min_timeout = 1,
+        .max_timeout = 0xFFFF
 };
 
 static int __init watchdog_init(void)
@@ -280,11 +169,14 @@ static int __init watchdog_init(void)
 
         /* Check that the soft_margin value is within it's range;
            if not reset to the default */
-        if (softdog_set_heartbeat(soft_margin)) {
-                softdog_set_heartbeat(TIMER_MARGIN);
+        if (soft_margin < 1 || soft_margin > 65535) {
                 pr_info("soft_margin must be 0 < soft_margin < 65536, using %d\n",
                         TIMER_MARGIN);
+                return -EINVAL;
         }
+        softdog_dev.timeout = soft_margin;
+
+        watchdog_set_nowayout(&softdog_dev, nowayout);
 
         ret = register_reboot_notifier(&softdog_notifier);
         if (ret) {
@@ -292,15 +184,13 @@ static int __init watchdog_init(void)
                 return ret;
         }
 
-        ret = misc_register(&softdog_miscdev);
+        ret = watchdog_register_device(&softdog_dev);
         if (ret) {
-                pr_err("cannot register miscdev on minor=%d (err=%d)\n",
-                       WATCHDOG_MINOR, ret);
                 unregister_reboot_notifier(&softdog_notifier);
                 return ret;
         }
 
-        pr_info("Software Watchdog Timer: 0.07 initialized. soft_noboot=%d soft_margin=%d sec soft_panic=%d (nowayout= %d)\n",
+        pr_info("Software Watchdog Timer: 0.08 initialized. soft_noboot=%d soft_margin=%d sec soft_panic=%d (nowayout=%d)\n",
                 soft_noboot, soft_margin, soft_panic, nowayout);
 
         return 0;
@@ -308,7 +198,7 @@ static int __init watchdog_init(void)
 
 static void __exit watchdog_exit(void)
 {
-        misc_deregister(&softdog_miscdev);
+        watchdog_unregister_device(&softdog_dev);
         unregister_reboot_notifier(&softdog_notifier);
 }