On R-Car Gen2 and RZ/G1 the watchdog IP clock needs to be always ON,
on R-Car Gen3 we power the IP down during suspend.
This commit adds suspend/resume support, so that the watchdog counting
"pauses" during suspend on all of the SoCs compatible with this driver
and on those we are now adding support for (R-Car Gen2 and RZ/G1).
Signed-off-by: Fabrizio Castro <fabrizio.castro@xxxxxxxxxxxxxx>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@xxxxxxxxxxxxxx>
---
v6->v7:
* backup and restore register RWTCNT instead of using rwdt_get_timeleft and
rwdt_set_timeleft
drivers/watchdog/renesas_wdt.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c
index 831ef83..024d54e 100644
--- a/drivers/watchdog/renesas_wdt.c
+++ b/drivers/watchdog/renesas_wdt.c
@@ -49,6 +49,7 @@ struct rwdt_priv {
void __iomem *base;
struct watchdog_device wdev;
unsigned long clk_rate;
+ u16 time_left;
u8 cks;
};
@@ -203,6 +204,30 @@ static int rwdt_remove(struct platform_device *pdev)
return 0;
}
+static int __maybe_unused rwdt_suspend(struct device *dev)
+{
+ struct rwdt_priv *priv = dev_get_drvdata(dev);
+
+ if (watchdog_active(&priv->wdev)) {
+ priv->time_left = readw(priv->base + RWTCNT);
+ rwdt_stop(&priv->wdev);
+ }
+ return 0;
+}
+
+static int __maybe_unused rwdt_resume(struct device *dev)
+{
+ struct rwdt_priv *priv = dev_get_drvdata(dev);
+
+ if (watchdog_active(&priv->wdev)) {
+ rwdt_start(&priv->wdev);
+ rwdt_write(priv, priv->time_left, RWTCNT);
+ }
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(rwdt_pm_ops, rwdt_suspend, rwdt_resume);
+
/*
* This driver does also fit for R-Car Gen2 (r8a779[0-4]) WDT. However, for SMP
* to work there, one also needs a RESET (RST) driver which does not exist yet
@@ -218,6 +243,7 @@ static struct platform_driver rwdt_driver = {
.driver = {
.name = "renesas_wdt",
.of_match_table = rwdt_ids,
+ .pm = &rwdt_pm_ops,
},
.probe = rwdt_probe,
.remove = rwdt_remove,
--
2.7.4
