From 8ae5908bcb59f322456a000d97db397fe839dfe4 Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Fri, 30 Aug 2013 12:38:34 +0200 Subject: pwm-backlight: Add power supply support Backlights require a power supply to work properly. This commit adds a regulator to power up and power down the backlight. Signed-off-by: Thierry Reding (cherry picked from commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9) --- drivers/video/backlight/pwm_bl.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'drivers') diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 7c564a09d399..60d489539b86 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -21,6 +21,7 @@ #include #include #include +#include #include struct pwm_bl_data { @@ -30,6 +31,7 @@ struct pwm_bl_data { unsigned int lth_brightness; unsigned int *levels; bool enabled; + struct regulator *power_supply; int enable_gpio; unsigned long enable_gpio_flags; int (*notify)(struct device *, @@ -60,6 +62,10 @@ static void pwm_backlight_power_on(struct pwm_bl_data *pb, int brightness, pwm_config(pb->pwm, duty_cycle, pb->period); + err = regulator_enable(pb->power_supply); + if (err < 0) + dev_err(pb->dev, "failed to enable power supply\n"); + if (gpio_is_valid(pb->enable_gpio)) { if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW) gpio_set_value(pb->enable_gpio, 0); @@ -86,6 +92,7 @@ static void pwm_backlight_power_off(struct pwm_bl_data *pb) gpio_set_value(pb->enable_gpio, 0); } + regulator_disable(pb->power_supply); pb->enabled = false; } @@ -268,6 +275,12 @@ static int pwm_backlight_probe(struct platform_device *pdev) } } + pb->power_supply = devm_regulator_get(&pdev->dev, "power"); + if (IS_ERR(pb->power_supply)) { + ret = PTR_ERR(pb->power_supply); + goto err_gpio; + } + pb->pwm = devm_pwm_get(&pdev->dev, NULL); if (IS_ERR(pb->pwm)) { dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n"); -- cgit v1.2.3