diff options
Diffstat (limited to 'drivers/video/backlight/pwm_bl.c')
| -rw-r--r-- | drivers/video/backlight/pwm_bl.c | 34 |
1 files changed, 27 insertions, 7 deletions
diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 1c2289ddd555..44ac5bde4e9d 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 <linux/delay.h> #include <linux/gpio/consumer.h> #include <linux/gpio.h> #include <linux/module.h> @@ -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 *, @@ -54,10 +57,14 @@ 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->post_pwm_on_delay) + msleep(pb->post_pwm_on_delay); + if (pb->enable_gpio) gpiod_set_value_cansleep(pb->enable_gpio, 1); - pwm_enable(pb->pwm); pb->enabled = true; } @@ -66,12 +73,15 @@ 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); + if (pb->pwm_off_delay) + msleep(pb->pwm_off_delay); + + pwm_config(pb->pwm, 0, pb->period); + pwm_disable(pb->pwm); + regulator_disable(pb->power_supply); pb->enabled = false; } @@ -177,6 +187,14 @@ 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; } @@ -275,6 +293,8 @@ 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); @@ -301,14 +321,14 @@ static int pwm_backlight_probe(struct platform_device *pdev) /* * If the GPIO is not known to be already configured as output, that - * is, if gpiod_get_direction returns either GPIOF_DIR_IN or -EINVAL, - * change the direction to output and set the GPIO as active. + * is, if gpiod_get_direction returns either 1 or -EINVAL, change the + * direction to output and set the GPIO as active. * Do not force the GPIO to active when it was already output as it * could cause backlight flickering or we would enable the backlight too * early. Leave the decision of the initial backlight state for later. */ if (pb->enable_gpio && - gpiod_get_direction(pb->enable_gpio) != GPIOF_DIR_OUT) + gpiod_get_direction(pb->enable_gpio) != 0) gpiod_direction_output(pb->enable_gpio, 1); pb->power_supply = devm_regulator_get(&pdev->dev, "power"); |