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authorThierry Reding <treding@nvidia.com>2013-10-07 11:32:02 +0200
committerMarcel Ziswiler <marcel.ziswiler@toradex.com>2018-03-28 18:39:46 +0200
commit7a3b733c6b3739708cb8d7c05be75903bbbdaffd (patch)
tree682cbe83968b44a1d9aef63cf70ddcfc76bc288b /drivers/video
parentae2b83192872b40a0f44e040b304ef828761f0ea (diff)
pwm-backlight: Refactor backlight power on/off
In preparation for adding an optional regulator and enable GPIO to the driver, split the power on and power off sequences into separate functions to reduce code duplication at the multiple call sites. Signed-off-by: Thierry Reding <treding@nvidia.com> (cherry picked from commit 62b744a87c1170b339f993aa3cfb22465974816a)
Diffstat (limited to 'drivers/video')
-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 ab6f4ca695cf..bf7891552ee6 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);