1 files changed, 29 insertions, 0 deletions

diff --git a/drivers/watchdog/sunxi_wdt.c b/drivers/watchdog/sunxi_wdt.c
index 693b9d2c6e39..60deb9d304c0 100644
--- a/drivers/watchdog/sunxi_wdt.c
+++ b/drivers/watchdog/sunxi_wdt.c
@@ -14,6 +14,7 @@
  */
 
 #include <linux/clk.h>
+#include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/io.h>
@@ -22,9 +23,12 @@
 #include <linux/moduleparam.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/reboot.h>
 #include <linux/types.h>
 #include <linux/watchdog.h>
 
+#include <asm/system_misc.h>
+
 #define WDT_MAX_TIMEOUT         16
 #define WDT_MIN_TIMEOUT         1
 #define WDT_MODE_TIMEOUT(n)     ((n) << 3)
@@ -70,6 +74,26 @@ static const int wdt_timeout_map[] = {
         [16] = 0xB, /* 16s */
 };
 
+static void __iomem *reboot_wdt_base;
+
+static void sun4i_wdt_restart(enum reboot_mode mode, const char *cmd)
+{
+        /* Enable timer and set reset bit in the watchdog */
+        writel(WDT_MODE_EN | WDT_MODE_RST_EN, reboot_wdt_base + WDT_MODE);
+
+        /*
+         * Restart the watchdog. The default (and lowest) interval
+         * value for the watchdog is 0.5s.
+         */
+        writel(WDT_CTRL_RELOAD, reboot_wdt_base + WDT_CTRL);
+
+        while (1) {
+                mdelay(5);
+                writel(WDT_MODE_EN | WDT_MODE_RST_EN,
+                       reboot_wdt_base + WDT_MODE);
+        }
+}
+
 static int sunxi_wdt_ping(struct watchdog_device *wdt_dev)
 {
         struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
@@ -181,6 +205,9 @@ static int sunxi_wdt_probe(struct platform_device *pdev)
         if (unlikely(err))
                 return err;
 
+        reboot_wdt_base = sunxi_wdt->wdt_base;
+        arm_pm_restart = sun4i_wdt_restart;
+
         dev_info(&pdev->dev, "Watchdog enabled (timeout=%d sec, nowayout=%d)",
                         sunxi_wdt->wdt_dev.timeout, nowayout);
 
@@ -191,6 +218,8 @@ static int sunxi_wdt_remove(struct platform_device *pdev)
 {
         struct sunxi_wdt_dev *sunxi_wdt = platform_get_drvdata(pdev);
 
+        arm_pm_restart = NULL;
+
         watchdog_unregister_device(&sunxi_wdt->wdt_dev);
         watchdog_set_drvdata(&sunxi_wdt->wdt_dev, NULL);