Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751843AbdGUKsf (ORCPT ); Fri, 21 Jul 2017 06:48:35 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:49978 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750802AbdGUKsc (ORCPT ); Fri, 21 Jul 2017 06:48:32 -0400 From: Enric Balletbo i Serra To: Thierry Reding , Lee Jones , Daniel Thompson , Jingoo Han , Bartlomiej Zolnierkiewicz , Rob Herring , Pavel Machek , Richard Purdie , Jacek Anaszewski , Heiko Stuebner Cc: linux-pwm@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, groeck@chromium.org, linux-rockchip@lists.infradead.org Subject: [PATCH v4 3/5] pwm-backlight: add support for PWM delays proprieties. Date: Fri, 21 Jul 2017 12:48:11 +0200 Message-Id: <20170721104813.5389-3-enric.balletbo@collabora.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20170721104813.5389-1-enric.balletbo@collabora.com> References: <20170721104813.5389-1-enric.balletbo@collabora.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3399 Lines: 102 Some panels (i.e. N116BGE-L41), in their power sequence specifications, request a delay between set the PWM signal and enable the backlight and between clear the PWM signal and disable the backlight. Add support for the new post-pwm-on-delay-ms and pwm-off-delay-ms proprieties to meet the timings. Signed-off-by: Enric Balletbo i Serra --- Changes since v3: - Use two named members instead of pwm_delay[] (Daniel and Pavel) - Use msleep instead of usleep_range. (Pavel) Changes since v2: - Move the pwm/enable sequence to another patch (Thierry Reding) Changes since v1: - As suggested by Daniel Thompson - Do not assume power-on delay and power-off delay will be the same - Move the check of dt property to the parse dt function. drivers/video/backlight/pwm_bl.c | 19 +++++++++++++++++++ include/linux/pwm_backlight.h | 2 ++ 2 files changed, 21 insertions(+) diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 909a686..6cf6109 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -10,6 +10,7 @@ * published by the Free Software Foundation. */ +#include #include #include #include @@ -35,6 +36,8 @@ struct pwm_bl_data { struct gpio_desc *enable_gpio; unsigned int scale; bool legacy; + unsigned int post_pwm_on_delay; + unsigned int pwm_off_delay; int (*notify)(struct device *, int brightness); void (*notify_after)(struct device *, @@ -56,6 +59,9 @@ static void pwm_backlight_power_on(struct pwm_bl_data *pb, int brightness) pwm_enable(pb->pwm); + if (pb->post_pwm_on_delay) + msleep(pb->post_pwm_on_delay); + if (pb->enable_gpio) gpiod_set_value_cansleep(pb->enable_gpio, 1); @@ -70,6 +76,9 @@ static void pwm_backlight_power_off(struct pwm_bl_data *pb) if (pb->enable_gpio) gpiod_set_value_cansleep(pb->enable_gpio, 0); + if (pb->pwm_off_delay) + msleep(pb->pwm_off_delay); + pwm_config(pb->pwm, 0, pb->period); pwm_disable(pb->pwm); @@ -175,6 +184,14 @@ static int pwm_backlight_parse_dt(struct device *dev, data->max_brightness--; } + /* + * These values are optional and set as 0 by default, the out values + * are modified only if a valid u32 value can be decoded. + */ + of_property_read_u32(node, "post-pwm-on-delay-ms", + &data->post_pwm_on_delay); + of_property_read_u32(node, "pwm-off-delay-ms", &data->pwm_off_delay); + data->enable_gpio = -EINVAL; return 0; } @@ -273,6 +290,8 @@ static int pwm_backlight_probe(struct platform_device *pdev) pb->exit = data->exit; pb->dev = &pdev->dev; pb->enabled = false; + pb->post_pwm_on_delay = data->post_pwm_on_delay; + pb->pwm_off_delay = data->pwm_off_delay; pb->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable", GPIOD_ASIS); diff --git a/include/linux/pwm_backlight.h b/include/linux/pwm_backlight.h index efdd922..62f59c4 100644 --- a/include/linux/pwm_backlight.h +++ b/include/linux/pwm_backlight.h @@ -13,6 +13,8 @@ struct platform_pwm_backlight_data { unsigned int lth_brightness; unsigned int pwm_period_ns; unsigned int *levels; + unsigned int post_pwm_on_delay; + unsigned int pwm_off_delay; /* TODO remove once all users are switched to gpiod_* API */ int enable_gpio; int (*init)(struct device *dev); -- 2.9.3