watchdog: s3c2410: convert to use the watchdog framework
authorWolfram Sang <w.sang@pengutronix.de>
Mon, 26 Sep 2011 13:40:14 +0000 (15:40 +0200)
committerWim Van Sebroeck <wim@iguana.be>
Sat, 5 Nov 2011 20:25:20 +0000 (21:25 +0100)
Make this driver a user of the watchdog framework and remove now
centrally handled parts. Tested on a mini2440.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
drivers/watchdog/Kconfig
drivers/watchdog/s3c2410_wdt.c

index 64c6752..40a36c5 100644 (file)
@@ -170,6 +170,7 @@ config HAVE_S3C2410_WATCHDOG
 config S3C2410_WATCHDOG
        tristate "S3C2410 Watchdog"
        depends on ARCH_S3C2410 || HAVE_S3C2410_WATCHDOG
+       select WATCHDOG_CORE
        help
          Watchdog timer block in the Samsung SoCs. This will reboot
          the system when the timer expires with the watchdog enabled.
index 30da88f..5de7e4f 100644 (file)
@@ -27,9 +27,8 @@
 #include <linux/moduleparam.h>
 #include <linux/types.h>
 #include <linux/timer.h>
-#include <linux/miscdevice.h>
+#include <linux/miscdevice.h> /* for MODULE_ALIAS_MISCDEV */
 #include <linux/watchdog.h>
-#include <linux/fs.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
@@ -38,6 +37,7 @@
 #include <linux/io.h>
 #include <linux/cpufreq.h>
 #include <linux/slab.h>
+#include <linux/err.h>
 
 #include <mach/map.h>
 
@@ -74,14 +74,12 @@ MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, "
                        "0 to reboot (default 0)");
 MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug (default 0)");
 
-static unsigned long open_lock;
 static struct device    *wdt_dev;      /* platform device attached to */
 static struct resource *wdt_mem;
 static struct resource *wdt_irq;
 static struct clk      *wdt_clock;
 static void __iomem    *wdt_base;
 static unsigned int     wdt_count;
-static char             expect_close;
 static DEFINE_SPINLOCK(wdt_lock);
 
 /* watchdog control routines */
@@ -93,11 +91,13 @@ static DEFINE_SPINLOCK(wdt_lock);
 
 /* functions */
 
-static void s3c2410wdt_keepalive(void)
+static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
 {
        spin_lock(&wdt_lock);
        writel(wdt_count, wdt_base + S3C2410_WTCNT);
        spin_unlock(&wdt_lock);
+
+       return 0;
 }
 
 static void __s3c2410wdt_stop(void)
@@ -109,14 +109,16 @@ static void __s3c2410wdt_stop(void)
        writel(wtcon, wdt_base + S3C2410_WTCON);
 }
 
-static void s3c2410wdt_stop(void)
+static int s3c2410wdt_stop(struct watchdog_device *wdd)
 {
        spin_lock(&wdt_lock);
        __s3c2410wdt_stop();
        spin_unlock(&wdt_lock);
+
+       return 0;
 }
 
-static void s3c2410wdt_start(void)
+static int s3c2410wdt_start(struct watchdog_device *wdd)
 {
        unsigned long wtcon;
 
@@ -142,6 +144,8 @@ static void s3c2410wdt_start(void)
        writel(wdt_count, wdt_base + S3C2410_WTCNT);
        writel(wtcon, wdt_base + S3C2410_WTCON);
        spin_unlock(&wdt_lock);
+
+       return 0;
 }
 
 static inline int s3c2410wdt_is_running(void)
@@ -149,7 +153,7 @@ static inline int s3c2410wdt_is_running(void)
        return readl(wdt_base + S3C2410_WTCON) & S3C2410_WTCON_ENABLE;
 }
 
-static int s3c2410wdt_set_heartbeat(int timeout)
+static int s3c2410wdt_set_heartbeat(struct watchdog_device *wdd, unsigned timeout)
 {
        unsigned long freq = clk_get_rate(wdt_clock);
        unsigned int count;
@@ -182,8 +186,6 @@ static int s3c2410wdt_set_heartbeat(int timeout)
                }
        }
 
-       tmr_margin = timeout;
-
        DBG("%s: timeout=%d, divisor=%d, count=%d (%08x)\n",
            __func__, timeout, divisor, count, count/divisor);
 
@@ -201,70 +203,6 @@ static int s3c2410wdt_set_heartbeat(int timeout)
        return 0;
 }
 
-/*
- *     /dev/watchdog handling
- */
-
-static int s3c2410wdt_open(struct inode *inode, struct file *file)
-{
-       if (test_and_set_bit(0, &open_lock))
-               return -EBUSY;
-
-       if (nowayout)
-               __module_get(THIS_MODULE);
-
-       expect_close = 0;
-
-       /* start the timer */
-       s3c2410wdt_start();
-       return nonseekable_open(inode, file);
-}
-
-static int s3c2410wdt_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)
-               s3c2410wdt_stop();
-       else {
-               dev_err(wdt_dev, "Unexpected close, not stopping watchdog\n");
-               s3c2410wdt_keepalive();
-       }
-       expect_close = 0;
-       clear_bit(0, &open_lock);
-       return 0;
-}
-
-static ssize_t s3c2410wdt_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;
-                       }
-               }
-               s3c2410wdt_keepalive();
-       }
-       return len;
-}
-
 #define OPTIONS (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE)
 
 static const struct watchdog_info s3c2410_wdt_ident = {
@@ -273,53 +211,17 @@ static const struct watchdog_info s3c2410_wdt_ident = {
        .identity         =     "S3C2410 Watchdog",
 };
 
-
-static long s3c2410wdt_ioctl(struct file *file,        unsigned int cmd,
-                                                       unsigned long arg)
-{
-       void __user *argp = (void __user *)arg;
-       int __user *p = argp;
-       int new_margin;
-
-       switch (cmd) {
-       case WDIOC_GETSUPPORT:
-               return copy_to_user(argp, &s3c2410_wdt_ident,
-                       sizeof(s3c2410_wdt_ident)) ? -EFAULT : 0;
-       case WDIOC_GETSTATUS:
-       case WDIOC_GETBOOTSTATUS:
-               return put_user(0, p);
-       case WDIOC_KEEPALIVE:
-               s3c2410wdt_keepalive();
-               return 0;
-       case WDIOC_SETTIMEOUT:
-               if (get_user(new_margin, p))
-                       return -EFAULT;
-               if (s3c2410wdt_set_heartbeat(new_margin))
-                       return -EINVAL;
-               s3c2410wdt_keepalive();
-               return put_user(tmr_margin, p);
-       case WDIOC_GETTIMEOUT:
-               return put_user(tmr_margin, p);
-       default:
-               return -ENOTTY;
-       }
-}
-
-/* kernel interface */
-
-static const struct file_operations s3c2410wdt_fops = {
-       .owner          = THIS_MODULE,
-       .llseek         = no_llseek,
-       .write          = s3c2410wdt_write,
-       .unlocked_ioctl = s3c2410wdt_ioctl,
-       .open           = s3c2410wdt_open,
-       .release        = s3c2410wdt_release,
+static struct watchdog_ops s3c2410wdt_ops = {
+       .owner = THIS_MODULE,
+       .start = s3c2410wdt_start,
+       .stop = s3c2410wdt_stop,
+       .ping = s3c2410wdt_keepalive,
+       .set_timeout = s3c2410wdt_set_heartbeat,
 };
 
-static struct miscdevice s3c2410wdt_miscdev = {
-       .minor          = WATCHDOG_MINOR,
-       .name           = "watchdog",
-       .fops           = &s3c2410wdt_fops,
+static struct watchdog_device s3c2410_wdd = {
+       .info = &s3c2410_wdt_ident,
+       .ops = &s3c2410wdt_ops,
 };
 
 /* interrupt handler code */
@@ -328,7 +230,7 @@ static irqreturn_t s3c2410wdt_irq(int irqno, void *param)
 {
        dev_info(wdt_dev, "watchdog timer expired (irq)\n");
 
-       s3c2410wdt_keepalive();
+       s3c2410wdt_keepalive(&s3c2410_wdd);
        return IRQ_HANDLED;
 }
 
@@ -349,14 +251,14 @@ static int s3c2410wdt_cpufreq_transition(struct notifier_block *nb,
                 * the watchdog is running.
                 */
 
-               s3c2410wdt_keepalive();
+               s3c2410wdt_keepalive(&s3c2410_wdd);
        } else if (val == CPUFREQ_POSTCHANGE) {
-               s3c2410wdt_stop();
+               s3c2410wdt_stop(&s3c2410_wdd);
 
-               ret = s3c2410wdt_set_heartbeat(tmr_margin);
+               ret = s3c2410wdt_set_heartbeat(&s3c2410_wdd, s3c2410_wdd.timeout);
 
                if (ret >= 0)
-                       s3c2410wdt_start();
+                       s3c2410wdt_start(&s3c2410_wdd);
                else
                        goto err;
        }
@@ -365,7 +267,8 @@ done:
        return 0;
 
  err:
-       dev_err(wdt_dev, "cannot set new value for timeout %d\n", tmr_margin);
+       dev_err(wdt_dev, "cannot set new value for timeout %d\n",
+                               s3c2410_wdd.timeout);
        return ret;
 }
 
@@ -396,10 +299,6 @@ static inline void s3c2410wdt_cpufreq_deregister(void)
 }
 #endif
 
-
-
-/* device interface */
-
 static int __devinit s3c2410wdt_probe(struct platform_device *pdev)
 {
        struct device *dev;
@@ -466,8 +365,8 @@ static int __devinit s3c2410wdt_probe(struct platform_device *pdev)
        /* see if we can actually set the requested timer margin, and if
         * not, try the default value */
 
-       if (s3c2410wdt_set_heartbeat(tmr_margin)) {
-               started = s3c2410wdt_set_heartbeat(
+       if (s3c2410wdt_set_heartbeat(&s3c2410_wdd, tmr_margin)) {
+               started = s3c2410wdt_set_heartbeat(&s3c2410_wdd,
                                        CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME);
 
                if (started == 0)
@@ -479,22 +378,21 @@ static int __devinit s3c2410wdt_probe(struct platform_device *pdev)
                                                        "cannot start\n");
        }
 
-       ret = misc_register(&s3c2410wdt_miscdev);
+       ret = watchdog_register_device(&s3c2410_wdd);
        if (ret) {
-               dev_err(dev, "cannot register miscdev on minor=%d (%d)\n",
-                       WATCHDOG_MINOR, ret);
+               dev_err(dev, "cannot register watchdog (%d)\n", ret);
                goto err_cpufreq;
        }
 
        if (tmr_atboot && started == 0) {
                dev_info(dev, "starting watchdog timer\n");
-               s3c2410wdt_start();
+               s3c2410wdt_start(&s3c2410_wdd);
        } else if (!tmr_atboot) {
                /* if we're not enabling the watchdog, then ensure it is
                 * disabled if it has been left running from the bootloader
                 * or other source */
 
-               s3c2410wdt_stop();
+               s3c2410wdt_stop(&s3c2410_wdd);
        }
 
        /* print out a statement of readiness */
@@ -530,7 +428,7 @@ static int __devinit s3c2410wdt_probe(struct platform_device *pdev)
 
 static int __devexit s3c2410wdt_remove(struct platform_device *dev)
 {
-       misc_deregister(&s3c2410wdt_miscdev);
+       watchdog_unregister_device(&s3c2410_wdd);
 
        s3c2410wdt_cpufreq_deregister();
 
@@ -550,7 +448,7 @@ static int __devexit s3c2410wdt_remove(struct platform_device *dev)
 
 static void s3c2410wdt_shutdown(struct platform_device *dev)
 {
-       s3c2410wdt_stop();
+       s3c2410wdt_stop(&s3c2410_wdd);
 }
 
 #ifdef CONFIG_PM
@@ -565,7 +463,7 @@ static int s3c2410wdt_suspend(struct platform_device *dev, pm_message_t state)
        wtdat_save = readl(wdt_base + S3C2410_WTDAT);
 
        /* Note that WTCNT doesn't need to be saved. */
-       s3c2410wdt_stop();
+       s3c2410wdt_stop(&s3c2410_wdd);
 
        return 0;
 }