From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lucas Stach Subject: Re: [RESEND PATCH] pwm-backlight: fix the panel power sequence Date: Fri, 16 Oct 2015 10:31:53 +0200 Message-ID: <1444984313.3180.6.camel@pengutronix.de> References: <1444959454-1516-1-git-send-email-yh.huang@mediatek.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from metis.ext.4.pengutronix.de ([92.198.50.35]:50980 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750851AbbJPIcA (ORCPT ); Fri, 16 Oct 2015 04:32:00 -0400 In-Reply-To: <1444959454-1516-1-git-send-email-yh.huang@mediatek.com> Sender: linux-pwm-owner@vger.kernel.org List-Id: linux-pwm@vger.kernel.org To: YH Huang Cc: Thierry Reding , Jingoo Han , Lee Jones , Matthias Brugger , linux-pwm@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, Tomi Valkeinen , linux-mediatek@lists.infradead.org, Sascha Hauer , yingjoe.chen@mediatek.com, Jean-Christophe Plagniol-Villard , linux-arm-kernel@lists.infradead.org Am Freitag, den 16.10.2015, 09:37 +0800 schrieb YH Huang: > In order to match the panel power sequence, disable the enable_gpio > in the probe function. Also, reorder the code in the power_on and > power_off function to match the timing. > You aren't specifying which panels power sequence you are matching here. Are you sure you aren't breaking other panels with this patch? Regards, Lucas > Signed-off-by: YH Huang > --- > drivers/video/backlight/pwm_bl.c | 15 +++++++++------ > 1 file changed, 9 insertions(+), 6 deletions(-) > > diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c > index eff379b..99eca1e 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(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(pb->enable_gpio, 0); > > + pwm_config(pb->pwm, 0, pb->period); > + pwm_disable(pb->pwm); > + > regulator_disable(pb->power_supply); > pb->enabled = false; > } > @@ -241,8 +242,7 @@ static int pwm_backlight_probe(struct platform_device *pdev) > pb->dev = &pdev->dev; > pb->enabled = false; > > - pb->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable", > - GPIOD_OUT_HIGH); > + pb->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable"); > if (IS_ERR(pb->enable_gpio)) { > ret = PTR_ERR(pb->enable_gpio); > goto err_alloc; > @@ -264,6 +264,9 @@ static int pwm_backlight_probe(struct platform_device *pdev) > pb->enable_gpio = gpio_to_desc(data->enable_gpio); > } > > + if (pb->enable_gpio) > + gpiod_direction_output(pb->enable_gpio, 0); > + > pb->power_supply = devm_regulator_get(&pdev->dev, "power"); > if (IS_ERR(pb->power_supply)) { > ret = PTR_ERR(pb->power_supply); -- Pengutronix e.K. | Lucas Stach | Industrial Linux Solutions | http://www.pengutronix.de/ |