summaryrefslogtreecommitdiffstats
path: root/drivers/video
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/video')
-rw-r--r--drivers/video/backlight/pwm_bl.c30
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)