[PATCH v5 5/7] watchdog: moxart: Register restart handler with kernel restart handler

Guenter Roeck
2014-07-18T07:34:51Z

The kernel now provides an API to trigger a system restart.
Register with it instead of setting arm_pm_restart.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
v5: Functions and variables renamed: *notifier -> *handler
v4: Set notifier priority to 128.
v3: Move struct notifier_block into struct moxart_wdt_dev.
Drop static variable previously needed to access struct moxart_wdt_dev
from notifier function; use container_of instead.
v2: No change.

drivers/watchdog/moxart_wdt.c | 32 ++++++++++++++++++++------------
1 file changed, 20 insertions(+), 12 deletions(-)

diff --git a/drivers/watchdog/moxart_wdt.c b/drivers/watchdog/moxart_wdt.c
index 4aa3a8a..a64405b 100644
--- a/drivers/watchdog/moxart_wdt.c
+++ b/drivers/watchdog/moxart_wdt.c
@@ -15,12 +15,12 @@
#include <linux/module.h>
#include <linux/err.h>
#include <linux/kernel.h>
+#include <linux/notifier.h>
#include <linux/platform_device.h>
+#include <linux/reboot.h>
#include <linux/watchdog.h>
#include <linux/moduleparam.h>

-#include <asm/system_misc.h>
-
#define REG_COUNT 0x4
#define REG_MODE 0x8
#define REG_ENABLE 0xC
@@ -29,17 +29,22 @@ struct moxart_wdt_dev {
struct watchdog_device dev;
void __iomem *base;
unsigned int clock_frequency;
+ struct notifier_block restart_handler;
};

-static struct moxart_wdt_dev *moxart_restart_ctx;
-
static int heartbeat;

-static void moxart_wdt_restart(enum reboot_mode reboot_mode, const char *cmd)
+static int moxart_restart_handle(struct notifier_block *this,
+ unsigned long mode, void *cmd)
{
- writel(1, moxart_restart_ctx->base + REG_COUNT);
- writel(0x5ab9, moxart_restart_ctx->base + REG_MODE);
- writel(0x03, moxart_restart_ctx->base + REG_ENABLE);
+ struct moxart_wdt_dev *moxart_wdt = container_of(this,
+ struct moxart_wdt_dev,
+ restart_handler);
+ writel(1, moxart_wdt->base + REG_COUNT);
+ writel(0x5ab9, moxart_wdt->base + REG_MODE);
+ writel(0x03, moxart_wdt->base + REG_ENABLE);
+
+ return NOTIFY_DONE;
}

static int moxart_wdt_stop(struct watchdog_device *wdt_dev)
@@ -136,8 +141,12 @@ static int moxart_wdt_probe(struct platform_device *pdev)
if (err)
return err;

- moxart_restart_ctx = moxart_wdt;
- arm_pm_restart = moxart_wdt_restart;
+ moxart_wdt->restart_handler.notifier_call = moxart_restart_handle;
+ moxart_wdt->restart_handler.priority = 128;
+ err = register_restart_handler(&moxart_wdt->restart_handler);
+ if (err)
+ dev_err(dev, "cannot register restart notifier (err=%d)\n",
+ err);

dev_dbg(dev, "Watchdog enabled (heartbeat=%d sec, nowayout=%d)\n",
moxart_wdt->dev.timeout, nowayout);
@@ -149,9 +158,8 @@ static int moxart_wdt_remove(struct platform_device *pdev)
{
struct moxart_wdt_dev *moxart_wdt = platform_get_drvdata(pdev);

- arm_pm_restart = NULL;
+ unregister_restart_handler(&moxart_wdt->restart_handler);
moxart_wdt_stop(&moxart_wdt->dev);
- watchdog_unregister_device(&moxart_wdt->dev);

return 0;
}
--
1.9.1