[PATCH] watchdog: sp805: add restart handler

[Jongsung Kim]

Add restart handler for SP805 watchdog so that the driver can be
used to reboot the system.

Signed-off-by: Jongsung Kim <neidhard....@lge.com>
---
 drivers/watchdog/sp805_wdt.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
index 01d816251302..01f7b6c29f92 100644
--- a/drivers/watchdog/sp805_wdt.c
+++ b/drivers/watchdog/sp805_wdt.c
@@ -23,6 +23,7 @@
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/pm.h>
+#include <linux/reboot.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/types.h>
@@ -67,6 +68,7 @@ struct sp805_wdt {
        struct clk                      *clk;
        struct amba_device              *adev;
        unsigned int                    load_val;
+       struct notifier_block           restart;
 };
 
 static bool nowayout = WATCHDOG_NOWAYOUT;
@@ -200,6 +202,18 @@ static const struct watchdog_ops wdt_ops = {
        .get_timeleft   = wdt_timeleft,
 };
 
+static int
+wdt_restart(struct notifier_block *this, unsigned long mode, void *cmd)
+{
+       struct sp805_wdt *wdt = container_of(this, struct sp805_wdt, restart);
+
+       writel_relaxed(0, wdt->base + WDTCONTROL);
+       writel_relaxed(0, wdt->base + WDTLOAD);
+       writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + WDTCONTROL);
+
+       return 0;
+}
+
 static int
 sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id)
 {
@@ -241,6 +255,10 @@ sp805_wdt_probe(struct amba_device *adev, const struct 
amba_id *id)
        }
        amba_set_drvdata(adev, wdt);
 
+       wdt->restart.notifier_call = wdt_restart;
+       wdt->restart.priority = 128;
+       register_restart_handler(&wdt->restart);
+
        dev_info(&adev->dev, "registration successful\n");
        return 0;
 
@@ -253,6 +271,7 @@ static int sp805_wdt_remove(struct amba_device *adev)
 {
        struct sp805_wdt *wdt = amba_get_drvdata(adev);
 
+       unregister_restart_handler(&wdt->restart);
        watchdog_unregister_device(&wdt->wdd);
        watchdog_set_drvdata(&wdt->wdd, NULL);
 
-- 
2.14.1