diff options
Diffstat (limited to 'drivers/video/backlight')
| -rw-r--r-- | drivers/video/backlight/pwm_bl.c | 30 |
1 files changed, 18 insertions, 12 deletions
diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 32e96e3525a1..f77a7b0ca5e6 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -45,21 +45,11 @@ struct pwm_bl_data { static void pwm_backlight_power_on(struct pwm_bl_data *pb, int brightness) { - unsigned int lth = pb->lth_brightness; int duty_cycle, err; if (pb->enabled) return; - if (pb->levels) - duty_cycle = pb->levels[brightness]; - else - duty_cycle = brightness; - - duty_cycle = (duty_cycle * (pb->period - lth) / pb->scale) + lth; - - 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"); @@ -94,10 +84,24 @@ static void pwm_backlight_power_off(struct pwm_bl_data *pb) pb->enabled = false; } +static int compute_duty_cycle(struct pwm_bl_data *pb, int brightness) +{ + unsigned int lth = pb->lth_brightness; + int duty_cycle; + + if (pb->levels) + duty_cycle = pb->levels[brightness]; + else + duty_cycle = brightness; + + return (duty_cycle * (pb->period - lth) / pb->scale) + lth; +} + static int pwm_backlight_update_status(struct backlight_device *bl) { struct pwm_bl_data *pb = bl_get_data(bl); int brightness = bl->props.brightness; + int duty_cycle; if (bl->props.power != FB_BLANK_UNBLANK || bl->props.fb_blank != FB_BLANK_UNBLANK || @@ -107,9 +111,11 @@ static int pwm_backlight_update_status(struct backlight_device *bl) if (pb->notify) brightness = pb->notify(pb->dev, brightness); - if (brightness > 0) + if (brightness > 0) { + duty_cycle = compute_duty_cycle(pb, brightness); + pwm_config(pb->pwm, duty_cycle, pb->period); pwm_backlight_power_on(pb, brightness); - else + } else pwm_backlight_power_off(pb); if (pb->notify_after) |