lkml.org 
[lkml]   [2017]   [Jul]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v4 1/5] pwm-backlight: enable/disable the PWM before/after LCD enable toggle.
Date
Before this patch the enable signal was set before the PWM signal and
vice-versa on power off. 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.

For reference the following panels have the mentioned sequence:
- N133HSE-EA1 (Innolux)
- N116BGE (Innolux)
- N156BGE-L21 (Innolux)
- B101EAN0 (Auo)
- B101AW03 (Auo)
- LTN101NT05 (Samsung)
- CLAA101WA01A (Chunghwa)

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
---
Changes since v3:
- List the part numbers for the panel checked (Daniel Thompson)
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
\
 
 \ /
  Last update: 2017-07-21 12:49    [W:0.114 / U:19.392 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site