[PATCH v3 1/5] pwm-backlight: enable/disable the PWM before/after LCD enable toggle.

From: Enric Balletbo i Serra
Date: Mon Jul 17 2017 - 17:28:34 EST


Before this patch the enable signal was set before the PWM signal and
vice-versa on power off. I guess that this sequence is wrong, at least,
it is on the different panels datasheets that I checked, so I inverted
the sequence to follow the specs.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
---
Changes since v2:
- Add this as a separate patch (Thierry Reding)
Changes since v1:
- None

drivers/video/backlight/pwm_bl.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c
index 002f1ce..909a686 100644
--- a/drivers/video/backlight/pwm_bl.c
+++ b/drivers/video/backlight/pwm_bl.c
@@ -54,10 +54,11 @@ static void pwm_backlight_power_on(struct pwm_bl_data *pb, int brightness)
if (err < 0)
dev_err(pb->dev, "failed to enable power supply\n");

+ pwm_enable(pb->pwm);
+
if (pb->enable_gpio)
gpiod_set_value_cansleep(pb->enable_gpio, 1);

- pwm_enable(pb->pwm);
pb->enabled = true;
}

@@ -66,12 +67,12 @@ static void pwm_backlight_power_off(struct pwm_bl_data *pb)
if (!pb->enabled)
return;

- pwm_config(pb->pwm, 0, pb->period);
- pwm_disable(pb->pwm);
-
if (pb->enable_gpio)
gpiod_set_value_cansleep(pb->enable_gpio, 0);

+ pwm_config(pb->pwm, 0, pb->period);
+ pwm_disable(pb->pwm);
+
regulator_disable(pb->power_supply);
pb->enabled = false;
}
--
2.9.3