watchdog: ep93xx_wdt: cleanup and let the core handle the heartbeat

Cleanup this driver and remove the 200ms heartbeat timer. The core now
has the ability to handle the heartbeat.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
[groeck: Dropped 0-initialization of static variable]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 44 insertions, 70 deletions

diff --git a/drivers/watchdog/ep93xx_wdt.c b/drivers/watchdog/ep93xx_wdt.c
index 8a6e1a7c63ae..f9b14e6efd9a 100644
--- a/drivers/watchdog/ep93xx_wdt.c
+++ b/drivers/watchdog/ep93xx_wdt.c
@@ -19,21 +19,13 @@
  * for us to rely on the user space daemon alone. So we ping the
  * wdt each ~200msec and eventually stop doing it if the user space
  * daemon dies.
- *
- * TODO:
- *
- *      - Test last reset from watchdog status
- *      - Add a few missing ioctls
  */
 
 #include <linux/platform_device.h>
 #include <linux/module.h>
 #include <linux/watchdog.h>
-#include <linux/timer.h>
 #include <linux/io.h>
 
-#define WDT_VERSION     "0.4"
-
 /* default timeout (secs) */
 #define WDT_TIMEOUT 30
 
@@ -41,59 +33,48 @@ static bool nowayout = WATCHDOG_NOWAYOUT;
 module_param(nowayout, bool, 0);
 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");
 
-static unsigned int timeout = WDT_TIMEOUT;
+static unsigned int timeout;
 module_param(timeout, uint, 0);
-MODULE_PARM_DESC(timeout,
-        "Watchdog timeout in seconds. (1<=timeout<=3600, default="
-                                __MODULE_STRING(WDT_TIMEOUT) ")");
-
-static void __iomem *mmio_base;
-static struct timer_list timer;
-static unsigned long next_heartbeat;
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds.");
 
 #define EP93XX_WATCHDOG         0x00
 #define EP93XX_WDSTATUS         0x04
 
-/* reset the wdt every ~200ms - the heartbeat of the device is 0.250 seconds*/
-#define WDT_INTERVAL (HZ/5)
-
-static void ep93xx_wdt_timer_ping(unsigned long data)
-{
-        if (time_before(jiffies, next_heartbeat))
-                writel(0x5555, mmio_base + EP93XX_WATCHDOG);
-
-        /* Re-set the timer interval */
-        mod_timer(&timer, jiffies + WDT_INTERVAL);
-}
+struct ep93xx_wdt_priv {
+        void __iomem *mmio;
+        struct watchdog_device wdd;
+};
 
 static int ep93xx_wdt_start(struct watchdog_device *wdd)
 {
-        next_heartbeat = jiffies + (timeout * HZ);
+        struct ep93xx_wdt_priv *priv = watchdog_get_drvdata(wdd);
 
-        writel(0xaaaa, mmio_base + EP93XX_WATCHDOG);
-        mod_timer(&timer, jiffies + WDT_INTERVAL);
+        writel(0xaaaa, priv->mmio + EP93XX_WATCHDOG);
 
         return 0;
 }
 
 static int ep93xx_wdt_stop(struct watchdog_device *wdd)
 {
-        del_timer_sync(&timer);
-        writel(0xaa55, mmio_base + EP93XX_WATCHDOG);
+        struct ep93xx_wdt_priv *priv = watchdog_get_drvdata(wdd);
+
+        writel(0xaa55, priv->mmio + EP93XX_WATCHDOG);
 
         return 0;
 }
 
-static int ep93xx_wdt_keepalive(struct watchdog_device *wdd)
+static int ep93xx_wdt_ping(struct watchdog_device *wdd)
 {
-        /* user land ping */
-        next_heartbeat = jiffies + (timeout * HZ);
+        struct ep93xx_wdt_priv *priv = watchdog_get_drvdata(wdd);
+
+        writel(0x5555, priv->mmio + EP93XX_WATCHDOG);
 
         return 0;
 }
 
 static const struct watchdog_info ep93xx_wdt_ident = {
         .options        = WDIOF_CARDRESET |
+                          WDIOF_SETTIMEOUT |
                           WDIOF_MAGICCLOSE |
                           WDIOF_KEEPALIVEPING,
         .identity       = "EP93xx Watchdog",
@@ -103,55 +84,50 @@ static const struct watchdog_ops ep93xx_wdt_ops = {
         .owner          = THIS_MODULE,
         .start          = ep93xx_wdt_start,
         .stop           = ep93xx_wdt_stop,
-        .ping           = ep93xx_wdt_keepalive,
-};
-
-static struct watchdog_device ep93xx_wdt_wdd = {
-        .info           = &ep93xx_wdt_ident,
-        .ops            = &ep93xx_wdt_ops,
+        .ping           = ep93xx_wdt_ping,
 };
 
 static int ep93xx_wdt_probe(struct platform_device *pdev)
 {
+        struct ep93xx_wdt_priv *priv;
+        struct watchdog_device *wdd;
         struct resource *res;
         unsigned long val;
-        int err;
+        int ret;
+
+        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
 
         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-        mmio_base = devm_ioremap_resource(&pdev->dev, res);
-        if (IS_ERR(mmio_base))
-                return PTR_ERR(mmio_base);
+        priv->mmio = devm_ioremap_resource(&pdev->dev, res);
+        if (IS_ERR(priv->mmio))
+                return PTR_ERR(priv->mmio);
 
-        if (timeout < 1 || timeout > 3600) {
-                timeout = WDT_TIMEOUT;
-                dev_warn(&pdev->dev,
-                        "timeout value must be 1<=x<=3600, using %d\n",
-                        timeout);
-        }
+        val = readl(priv->mmio + EP93XX_WATCHDOG);
 
-        val = readl(mmio_base + EP93XX_WATCHDOG);
-        ep93xx_wdt_wdd.bootstatus = (val & 0x01) ? WDIOF_CARDRESET : 0;
-        ep93xx_wdt_wdd.timeout = timeout;
-        ep93xx_wdt_wdd.parent = &pdev->dev;
+        wdd = &priv->wdd;
+        wdd->bootstatus = (val & 0x01) ? WDIOF_CARDRESET : 0;
+        wdd->info = &ep93xx_wdt_ident;
+        wdd->ops = &ep93xx_wdt_ops;
+        wdd->min_timeout = 1;
+        wdd->max_hw_heartbeat_ms = 200;
+        wdd->parent = &pdev->dev;
 
-        watchdog_set_nowayout(&ep93xx_wdt_wdd, nowayout);
+        watchdog_set_nowayout(wdd, nowayout);
 
-        setup_timer(&timer, ep93xx_wdt_timer_ping, 1);
+        wdd->timeout = WDT_TIMEOUT;
+        watchdog_init_timeout(wdd, timeout, &pdev->dev);
 
-        err = watchdog_register_device(&ep93xx_wdt_wdd);
-        if (err)
-                return err;
+        watchdog_set_drvdata(wdd, priv);
 
-        dev_info(&pdev->dev,
-                "EP93XX watchdog, driver version " WDT_VERSION "%s\n",
-                (val & 0x08) ? " (nCS1 disable detected)" : "");
+        ret = devm_watchdog_register_device(&pdev->dev, wdd);
+        if (ret)
+                return ret;
 
-        return 0;
-}
+        dev_info(&pdev->dev, "EP93XX watchdog driver %s\n",
+                (val & 0x08) ? " (nCS1 disable detected)" : "");
 
-static int ep93xx_wdt_remove(struct platform_device *pdev)
-{
-        watchdog_unregister_device(&ep93xx_wdt_wdd);
         return 0;
 }
 
@@ -160,7 +136,6 @@ static struct platform_driver ep93xx_wdt_driver = {
                 .name   = "ep93xx-wdt",
         },
         .probe          = ep93xx_wdt_probe,
-        .remove         = ep93xx_wdt_remove,
 };
 
 module_platform_driver(ep93xx_wdt_driver);
@@ -170,4 +145,3 @@ MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
 MODULE_DESCRIPTION("EP93xx Watchdog");
 MODULE_LICENSE("GPL");
-MODULE_VERSION(WDT_VERSION);