Commit 9c5f91cc authored by Enric Balletbo i Serra's avatar Enric Balletbo i Serra Committed by Greg Kroah-Hartman

pwm-backlight: Enable/disable the PWM before/after LCD enable toggle.

commit 5fb5caee upstream.

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: default avatarEnric Balletbo i Serra <>
Acked-by: default avatarDaniel Thompson <>
Acked-by: default avatarJingoo Han <>
Acked-by: default avatarThierry Reding <>
Signed-off-by: default avatarLee Jones <>
Signed-off-by: default avatarArnd Bergmann <>
Signed-off-by: default avatarGreg Kroah-Hartman <>
parent 423f2c97
......@@ -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");
if (pb->enable_gpio)
gpiod_set_value_cansleep(pb->enable_gpio, 1);
pb->enabled = true;
......@@ -66,12 +67,12 @@ static void pwm_backlight_power_off(struct pwm_bl_data *pb)
if (!pb->enabled)
pwm_config(pb->pwm, 0, pb->period);
if (pb->enable_gpio)
gpiod_set_value_cansleep(pb->enable_gpio, 0);
pwm_config(pb->pwm, 0, pb->period);
pb->enabled = false;
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