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path: root/drivers/video/backlight/pwm_bl.c
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Diffstat (limited to 'drivers/video/backlight/pwm_bl.c')
-rw-r--r--drivers/video/backlight/pwm_bl.c53
1 files changed, 31 insertions, 22 deletions
diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c
index 774bce38ba42..ab9d5e6012a4 100644
--- a/drivers/video/backlight/pwm_bl.c
+++ b/drivers/video/backlight/pwm_bl.c
@@ -35,6 +35,31 @@ struct pwm_bl_data {
void (*exit)(struct device *);
};
+static void pwm_backlight_power_on(struct pwm_bl_data *pb, int brightness,
+ int max)
+{
+ int duty_cycle, err;
+
+ if (pb->levels) {
+ duty_cycle = pb->levels[brightness];
+ max = pb->levels[max];
+ } else {
+ duty_cycle = brightness;
+ }
+
+ duty_cycle = (duty_cycle * (pb->period - pb->lth_brightness) / max) +
+ pb->lth_brightness;
+
+ pwm_config(pb->pwm, duty_cycle, pb->period);
+ pwm_enable(pb->pwm);
+}
+
+static void pwm_backlight_power_off(struct pwm_bl_data *pb)
+{
+ pwm_config(pb->pwm, 0, pb->period);
+ pwm_disable(pb->pwm);
+}
+
static int pwm_backlight_update_status(struct backlight_device *bl)
{
struct pwm_bl_data *pb = bl_get_data(bl);
@@ -49,24 +74,10 @@ static int pwm_backlight_update_status(struct backlight_device *bl)
if (pb->notify)
brightness = pb->notify(pb->dev, brightness);
- if (brightness == 0) {
- pwm_config(pb->pwm, 0, pb->period);
- pwm_disable(pb->pwm);
- } else {
- int duty_cycle;
-
- if (pb->levels) {
- duty_cycle = pb->levels[brightness];
- max = pb->levels[max];
- } else {
- duty_cycle = brightness;
- }
-
- duty_cycle = pb->lth_brightness +
- (duty_cycle * (pb->period - pb->lth_brightness) / max);
- pwm_config(pb->pwm, duty_cycle, pb->period);
- pwm_enable(pb->pwm);
- }
+ if (brightness > 0)
+ pwm_backlight_power_on(pb, brightness, max);
+ else
+ pwm_backlight_power_off(pb);
if (pb->notify_after)
pb->notify_after(pb->dev, brightness);
@@ -267,8 +278,7 @@ static int pwm_backlight_remove(struct platform_device *pdev)
struct pwm_bl_data *pb = bl_get_data(bl);
backlight_device_unregister(bl);
- pwm_config(pb->pwm, 0, pb->period);
- pwm_disable(pb->pwm);
+ pwm_backlight_power_off(pb);
if (pb->exit)
pb->exit(&pdev->dev);
@@ -285,8 +295,7 @@ static int pwm_backlight_suspend(struct device *dev)
if (pb->notify)
pb->notify(pb->dev, 0);
- pwm_config(pb->pwm, 0, pb->period);
- pwm_disable(pb->pwm);
+ pwm_backlight_power_off(pb);
if (pb->notify_after)
pb->notify_after(pb->dev, 0);