Re: [PATCH 3/3] watchdog: da9062: add power management ops

From: Guenter Roeck
Date: Thu Feb 06 2020 - 09:28:54 EST


On 2/6/20 1:00 AM, Marco Felsch wrote:
Hi Guenter,

On 20-01-23 12:51, Guenter Roeck wrote:
On Wed, Jan 08, 2020 at 10:57:04AM +0100, Marco Felsch wrote:
Disable the watchdog during suspend if it is enabled and re-enable it on
resume. So we can sleep without the interruptions.

Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@xxxxxxxxxxx>

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

I got an kbuild email so I checked the linux-next master tree. On
linux-next this patch isn't used instead the old v1 was used...


FWIW, The subject line of this patch doesn't include "v2".

Guenter

Regards,
Marco

---
v2:
- add dlg,use-sw-pm check to differentiate between automatic and manual
disabling/enabling.
---
drivers/watchdog/da9062_wdt.c | 37 +++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)

diff --git a/drivers/watchdog/da9062_wdt.c b/drivers/watchdog/da9062_wdt.c
index e149e66a6ea9..c9b9d6394525 100644
--- a/drivers/watchdog/da9062_wdt.c
+++ b/drivers/watchdog/da9062_wdt.c
@@ -15,6 +15,7 @@
#include <linux/jiffies.h>
#include <linux/mfd/da9062/registers.h>
#include <linux/mfd/da9062/core.h>
+#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/of.h>
@@ -30,6 +31,7 @@ static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
struct da9062_watchdog {
struct da9062 *hw;
struct watchdog_device wdtdev;
+ bool use_sw_pm;
};
static unsigned int da9062_wdt_timeout_to_sel(unsigned int secs)
@@ -198,6 +200,8 @@ static int da9062_wdt_probe(struct platform_device *pdev)
if (!wdt)
return -ENOMEM;
+ wdt->use_sw_pm = device_property_present(dev, "dlg,use-sw-pm");
+
wdt->hw = chip;
wdt->wdtdev.info = &da9062_watchdog_info;
@@ -212,6 +216,7 @@ static int da9062_wdt_probe(struct platform_device *pdev)
watchdog_set_restart_priority(&wdt->wdtdev, 128);
watchdog_set_drvdata(&wdt->wdtdev, wdt);
+ dev_set_drvdata(dev, &wdt->wdtdev);
ret = devm_watchdog_register_device(dev, &wdt->wdtdev);
if (ret < 0)
@@ -220,10 +225,42 @@ static int da9062_wdt_probe(struct platform_device *pdev)
return da9062_wdt_ping(&wdt->wdtdev);
}
+static int __maybe_unused da9062_wdt_suspend(struct device *dev)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
+
+ if (!wdt->use_sw_pm)
+ return 0;
+
+ if (watchdog_active(wdd))
+ return da9062_wdt_stop(wdd);
+
+ return 0;
+}
+
+static int __maybe_unused da9062_wdt_resume(struct device *dev)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
+
+ if (!wdt->use_sw_pm)
+ return 0;
+
+ if (watchdog_active(wdd))
+ return da9062_wdt_start(wdd);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(da9062_wdt_pm_ops,
+ da9062_wdt_suspend, da9062_wdt_resume);
+
static struct platform_driver da9062_wdt_driver = {
.probe = da9062_wdt_probe,
.driver = {
.name = "da9062-watchdog",
+ .pm = &da9062_wdt_pm_ops,
.of_match_table = da9062_compatible_id_table,
},
};