diff options
| author | Thierry Reding <treding@nvidia.com> | 2013-08-30 12:38:34 +0200 |
|---|---|---|
| committer | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2018-03-28 18:39:56 +0200 |
| commit | 8ae5908bcb59f322456a000d97db397fe839dfe4 (patch) | |
| tree | 9d1a18cbc314bd09aa16cf0aa6208e8d88a86d29 | |
| parent | 8431712fa81721de1e675d98f19d2de9ddc96195 (diff) | |
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 <treding@nvidia.com>
(cherry picked from commit 22ceeee16eb8f0d04de3ef43a5174fb30ec18af9)
| -rw-r--r-- | Documentation/devicetree/bindings/video/backlight/pwm-backlight.txt | 2 | ||||
| -rw-r--r-- | drivers/video/backlight/pwm_bl.c | 13 |
2 files changed, 15 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/video/backlight/pwm-backlight.txt b/Documentation/devicetree/bindings/video/backlight/pwm-backlight.txt index 72810cc2dbc1..764db86d441a 100644 --- a/Documentation/devicetree/bindings/video/backlight/pwm-backlight.txt +++ b/Documentation/devicetree/bindings/video/backlight/pwm-backlight.txt @@ -10,6 +10,7 @@ Required properties: last value in the array represents a 100% duty cycle (brightest). - default-brightness-level: the default brightness level (index into the array defined by the "brightness-levels" property) + - power-supply: regulator for supply voltage Optional properties: - pwm-names: a list of names for the PWM devices specified in the @@ -29,5 +30,6 @@ Example: brightness-levels = <0 4 8 16 32 64 128 255>; default-brightness-level = <6>; + power-supply = <&vdd_bl_reg>; enable-gpios = <&gpio 58 0>; }; 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 <linux/err.h> #include <linux/pwm.h> #include <linux/pwm_backlight.h> +#include <linux/regulator/consumer.h> #include <linux/slab.h> 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"); |