Most of the watchdog code is duplicated between the machine restart code andThe only condition where this can happen if is there is a race between the calling
the watchdog driver. Add the restart hook to the watchdog driver, to be able to
remove it from the machine code eventually.
Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
---
drivers/watchdog/sunxi_wdt.c | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/drivers/watchdog/sunxi_wdt.c b/drivers/watchdog/sunxi_wdt.c
index cd00a7836cdc..0644c45d2b60 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 +74,30 @@ static const int wdt_timeout_map[] = {
[16] = 0b1011, /* 16s */
};
+static struct sunxi_wdt_dev *sunxi_restart_ctx;
+
+static void sun4i_wdt_restart(enum reboot_mode mode, const char *cmd)
+{
+ if (!sunxi_restart_ctx)
+ return;
+
+ /* Enable timer and set reset bit in the watchdog */
+ writel(WDT_MODE_EN | WDT_MODE_RST_EN,
+ sunxi_restart_ctx->wdt_base + WDT_MODE);
+
+ /*
+ * Restart the watchdog. The default (and lowest) interval
+ * value for the watchdog is 0.5s.
+ */
+ writel(WDT_CTRL_RELOAD, sunxi_restart_ctx->wdt_base + WDT_CTRL);
+
+ while (1) {
+ mdelay(5);
+ writel(WDT_MODE_EN | WDT_MODE_RST_EN,
+ sunxi_restart_ctx->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 +209,9 @@ static int sunxi_wdt_probe(struct platform_device *pdev)
if (unlikely(err))
return err;
+ sunxi_restart_ctx = sunxi_wdt;
+ 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 +222,8 @@ 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);