The pwm-fan driver uses full PWM (255) duty cycle at startup, which may not
always be desirable because of noise or power consumption peaks, so support
an optional "default-pwm" property that can be used to specify the default
PWM duty cycle.
Signed-off-by: Peter Korsgaard <peter@xxxxxxxxxxxxx>
---
drivers/hwmon/pwm-fan.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index 53a1a968d00d..09e9047635f7 100644
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -499,6 +499,7 @@ static int pwm_fan_probe(struct platform_device *pdev)
const struct hwmon_channel_info **channels;
u32 pwm_min_from_stopped = 0;
u32 *fan_channel_config;
+ u32 default_pwm;
int channel_count = 1; /* We always have a PWM channel. */
int i;
@@ -545,11 +546,15 @@ static int pwm_fan_probe(struct platform_device *pdev)
ctx->enable_mode = pwm_disable_reg_enable;
+ ret = device_property_read_u32(dev, "default-pwm", &default_pwm);
+ if (ret)
+ default_pwm = MAX_PWM;
+
/*
- * Set duty cycle to maximum allowed and enable PWM output as well as
+ * Set duty cycle to default and enable PWM output as well as
* the regulator. In case of error nothing is changed
*/
- ret = set_pwm(ctx, MAX_PWM);
+ ret = set_pwm(ctx, default_pwm);
if (ret) {
dev_err(dev, "Failed to configure PWM: %d\n", ret);
return ret;
--
2.39.5
