[PATCH 4/4] watchdog: imgpdc: Add reboot support

Andrew Bresticker
2015-03-31T18:49:11Z

Register a restart handler that will restart the system by writing
to the watchdog's SOFT_RESET register.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
---
drivers/watchdog/imgpdc_wdt.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/drivers/watchdog/imgpdc_wdt.c b/drivers/watchdog/imgpdc_wdt.c
index aef3596..d9eaee3 100644
--- a/drivers/watchdog/imgpdc_wdt.c
+++ b/drivers/watchdog/imgpdc_wdt.c
@@ -16,6 +16,7 @@
#include <linux/log2.h>
#include <linux/module.h>
#include <linux/platform_device.h>
+#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/watchdog.h>

@@ -57,6 +58,7 @@ struct pdc_wdt_dev {
struct clk *wdt_clk;
struct clk *sys_clk;
void __iomem *base;
+ struct notifier_block restart_handler;
};

static int pdc_wdt_keepalive(struct watchdog_device *wdt_dev)
@@ -130,6 +132,18 @@ static const struct watchdog_ops pdc_wdt_ops = {
.set_timeout = pdc_wdt_set_timeout,
};

+static int pdc_wdt_restart(struct notifier_block *this, unsigned long mode,
+ void *cmd)
+{
+ struct pdc_wdt_dev *wdt = container_of(this, struct pdc_wdt_dev,
+ restart_handler);
+
+ /* Assert SOFT_RESET */
+ writel(0x1, wdt->base + PDC_WDT_SOFT_RESET);
+
+ return NOTIFY_OK;
+}
+
static int pdc_wdt_probe(struct platform_device *pdev)
{
int ret, val;
@@ -240,6 +254,13 @@ static int pdc_wdt_probe(struct platform_device *pdev)
if (ret)
goto disable_wdt_clk;

+ pdc_wdt->restart_handler.notifier_call = pdc_wdt_restart;
+ pdc_wdt->restart_handler.priority = 128;
+ ret = register_restart_handler(&pdc_wdt->restart_handler);
+ if (ret)
+ dev_warn(&pdev->dev, "failed to register restart handler: %d\n",
+ ret);
+
return 0;

disable_wdt_clk:
--
2.2.0.rc0.207.ga3a616c