From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: [BACKPORT 4.14.y 7/8] pwm-backlight: Enable/disable the PWM before/after LCD enable toggle. Date: Fri, 22 Mar 2019 17:17:22 +0100 Message-ID: <20190322161727.1153278-8-arnd@arndb.de> References: <20190322161727.1153278-1-arnd@arndb.de> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190322161727.1153278-1-arnd@arndb.de> Sender: stable-owner@vger.kernel.org To: stable@vger.kernel.org, Thierry Reding , Lee Jones , Daniel Thompson , Jingoo Han , Bartlomiej Zolnierkiewicz Cc: Enric Balletbo i Serra , Arnd Bergmann , Wolfram Sang , linux-pwm@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-pwm@vger.kernel.org From: Enric Balletbo i Serra 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 Acked-by: Daniel Thompson Acked-by: Jingoo Han Acked-by: Thierry Reding Signed-off-by: Lee Jones (cherry picked from commit 5fb5caee92ba35a4a3baa61d45a78eb057e2c031) Signed-off-by: Arnd Bergmann --- 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 0fa7d2bd0e48..155153ecb894 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; } -- 2.20.0