Re: [PATCH 2/2] watchdog: sama5d4: Implement resume hook

From: Guenter Roeck
Date: Sat Feb 04 2017 - 18:57:51 EST


On 01/30/2017 09:18 AM, Alexandre Belloni wrote:
When resuming for the deepest state on sama5d2, it is necessary to restore
MR as the registers are lost.

Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
---
drivers/watchdog/sama5d4_wdt.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c
index 6dd07bef515a..de8ff10a032e 100644
--- a/drivers/watchdog/sama5d4_wdt.c
+++ b/drivers/watchdog/sama5d4_wdt.c
@@ -258,11 +258,28 @@ static const struct of_device_id sama5d4_wdt_of_match[] = {
};
MODULE_DEVICE_TABLE(of, sama5d4_wdt_of_match);

+#ifdef CONFIG_PM_SLEEP
+static int sama5d4_wdt_resume(struct device *dev)
+{
+ struct sama5d4_wdt *wdt = dev_get_drvdata(dev);
+
+ wdt_write(wdt, AT91_WDT_MR, wdt->mr & ~AT91_WDT_WDDIS);
+ if (wdt->mr & AT91_WDT_WDDIS)
+ wdt_write(wdt, AT91_WDT_MR, wdt->mr);
+
+ return 0;
+}
+#endif
+

First time I ever see a system which doesn't need a matching suspend function.
I assume that isn't needed. With that,

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

Thanks,
Guenter

+static SIMPLE_DEV_PM_OPS(sama5d4_wdt_pm_ops, NULL,
+ sama5d4_wdt_resume);
+
static struct platform_driver sama5d4_wdt_driver = {
.probe = sama5d4_wdt_probe,
.remove = sama5d4_wdt_remove,
.driver = {
.name = "sama5d4_wdt",
+ .pm = &sama5d4_wdt_pm_ops,
.of_match_table = sama5d4_wdt_of_match,
}
};