From mboxrd@z Thu Jan 1 00:00:00 1970 From: Enric Balletbo i Serra Date: Fri, 01 Dec 2017 12:06:47 +0000 Subject: [PATCH v5 1/5] pwm-backlight: enable/disable the PWM before/after LCD enable toggle. Message-Id: <20171201120651.29633-1-enric.balletbo@collabora.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Lee Jones , Daniel Thompson , Jingoo Han , Rob Herring , Pavel Machek , Heiko Stuebner Cc: Thierry Reding , Bartlomiej Zolnierkiewicz , Richard Purdie , Jacek Anaszewski , linux-pwm@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, groeck@chromium.org, linux-rockchip@lists.infradead.org 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 --- Changes since v4: - Rebase on top of mainline. - Add the acks from Daniel Thompson and Jingoo Han. 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 1c2289d..698ec68 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