[PATCH 1/2] hwmon: (pwm-fan) add option to stop fan on shutdown

Akinobu Mita
2019-12-22T14:10:57Z

The pwm-fan driver leaves the fun running when shutting down the system.
(On the other hand the gpio-fan driver stops it.)

This adds an optional property "disable-state-shutdown" in case someone
wants to stop the fun running when shutting down the system.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Kamil Debski <kamil@wypas.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
---
drivers/hwmon/pwm-fan.c | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index 42ffd2e..8775d37 100644
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -33,6 +33,7 @@ struct pwm_fan_ctx {
u8 pulses_per_revolution;
ktime_t sample_start;
struct timer_list rpm_timer;
+ bool disable_state_shutdown;

unsigned int pwm_value;
unsigned int pwm_fan_state;
@@ -292,6 +293,9 @@ static int pwm_fan_probe(struct platform_device *pdev)

mutex_init(&ctx->lock);

+ ctx->disable_state_shutdown =
+ of_property_read_bool(dev->of_node, "disable-state-shutdown");
+
ctx->pwm = devm_of_pwm_get(dev, dev->of_node, NULL);
if (IS_ERR(ctx->pwm)) {
ret = PTR_ERR(ctx->pwm);
@@ -390,8 +394,7 @@ static int pwm_fan_probe(struct platform_device *pdev)
return 0;
}

-#ifdef CONFIG_PM_SLEEP
-static int pwm_fan_suspend(struct device *dev)
+static int pwm_fan_disable(struct device *dev)
{
struct pwm_fan_ctx *ctx = dev_get_drvdata(dev);
struct pwm_args args;
@@ -418,6 +421,22 @@ static int pwm_fan_suspend(struct device *dev)
return 0;
}

+static void pwm_fan_shutdown(struct platform_device *pdev)
+{
+ struct pwm_fan_ctx *ctx = platform_get_drvdata(pdev);
+
+ if (!ctx->disable_state_shutdown)
+ return;
+
+ pwm_fan_disable(&pdev->dev);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int pwm_fan_suspend(struct device *dev)
+{
+ return pwm_fan_disable(dev);
+}
+
static int pwm_fan_resume(struct device *dev)
{
struct pwm_fan_ctx *ctx = dev_get_drvdata(dev);
@@ -455,6 +474,7 @@ MODULE_DEVICE_TABLE(of, of_pwm_fan_match);

static struct platform_driver pwm_fan_driver = {
.probe = pwm_fan_probe,
+ .shutdown = pwm_fan_shutdown,
.driver = {
.name = "pwm-fan",
.pm = &pwm_fan_pm,
--
2.7.4