backlight:change min_brightness calculate,change suspend status ctl

diff --git a/drivers/video/backlight/rk29_backlight.c b/drivers/video/backlight/rk29_backlight.c
index cad9ca6543d579b7b5c357ac58bdca8555d7661b..55d0804c25fac32d01057a57b4d51047444aed0c 100755 (executable)
--- a/drivers/video/backlight/rk29_backlight.c
+++ b/drivers/video/backlight/rk29_backlight.c
@@ -90,19 +90,30 @@ static ssize_t backlight_read(struct device *dev,
 }
 static DEVICE_ATTR(rk29backlight, 0660, backlight_read, backlight_write);
 
+static DEFINE_MUTEX(backlight_mutex);
+
 static int rk29_bl_update_status(struct backlight_device *bl)
 {
        u32 divh,div_total;
        struct rk29_bl_info *rk29_bl_info = bl_get_data(bl);
        u32 id = rk29_bl_info->pwm_id;
        u32 ref = rk29_bl_info->bl_ref;
-       int brightness = bl->props.brightness;
+       int brightness = 0;
        
-       if (suspend_flag)
-               return 0;       
-
-       if (bl->props.brightness < rk29_bl_info->min_brightness && bl->props.brightness != 0)   /*avoid can't view screen when close backlight*/
-               brightness = rk29_bl_info->min_brightness;
+       mutex_lock(&backlight_mutex);
+//BL_CORE_DRIVER2 is the flag if backlight is into early_suspend.
+       if (suspend_flag && (bl->props.state & BL_CORE_DRIVER2))
+           goto out;
+
+       brightness = bl->props.brightness;
+       if(rk29_bl_info->min_brightness){
+           if(brightness){
+               brightness = brightness*(256 - rk29_bl_info->min_brightness);
+               brightness = (brightness>>8) + rk29_bl_info->min_brightness;
+           }
+           if(brightness > 255)
+               brightness = 255;
+       }
 
        if (bl->props.power != FB_BLANK_UNBLANK)
                brightness = 0;
@@ -110,18 +121,15 @@ static int rk29_bl_update_status(struct backlight_device *bl)
        if (bl->props.fb_blank != FB_BLANK_UNBLANK)
                brightness = 0; 
 
-       if (bl->props.state & BL_CORE_SUSPENDED)
+       if ((bl->props.state & BL_CORE_DRIVER2) && !suspend_flag ){
                brightness = 0;
-
-       div_total = read_pwm_reg(id, PWM_REG_LRC);
-       if (ref) {
-               divh = div_total*brightness/BL_STEP;
-       } else {
-               divh = div_total*(BL_STEP-brightness)/BL_STEP;
+               suspend_flag = 1;
+       }else if(!(bl->props.state & BL_CORE_DRIVER2) && suspend_flag ){
+               suspend_flag = 0;
        }
-       write_pwm_reg(id, PWM_REG_HRC, divh);
 
-       if ((bl->props.state & BL_CORE_DRIVER1) && brightness ==0 ){  //BL_CORE_DRIVER1 is the flag if backlight is closed.
+//BL_CORE_DRIVER1 is the flag if backlight pwm is closed.
+       if ((bl->props.state & BL_CORE_DRIVER1) && brightness ==0 ){  
                bl->props.state &= ~BL_CORE_DRIVER1;
                clk_disable(pwm_clk);
                if (rk29_bl_info->pwm_suspend)
@@ -131,9 +139,20 @@ static int rk29_bl_update_status(struct backlight_device *bl)
                if (rk29_bl_info->pwm_resume)
                        rk29_bl_info->pwm_resume();
                clk_enable(pwm_clk);
+               msleep(1);
        }
 
+       div_total = read_pwm_reg(id, PWM_REG_LRC);
+       if (ref) {
+               divh = div_total*brightness/BL_STEP;
+       } else {
+               divh = div_total*(BL_STEP-brightness)/BL_STEP;
+       }
+       write_pwm_reg(id, PWM_REG_HRC, divh);
+
        DBG("%s:line=%d,brightness = %d, div_total = %d, divh = %d state=%x \n",__FUNCTION__,__LINE__,brightness, div_total, divh,bl->props.state);
+out:
+       mutex_unlock(&backlight_mutex);
        return 0;
 }
 
@@ -164,6 +183,7 @@ static struct backlight_ops rk29_bl_ops = {
 
 static void rk29_backlight_work_func(struct work_struct *work)
 {
+       rk29_bl->props.state &= ~BL_CORE_DRIVER2;
        rk29_bl_update_status(rk29_bl);
 }
 static DECLARE_DELAYED_WORK(rk29_backlight_work, rk29_backlight_work_func);
@@ -176,13 +196,14 @@ static void rk29_bl_suspend(struct early_suspend *h)
 
        cancel_delayed_work_sync(&rk29_backlight_work);
 
+       rk29_bl->props.state |= BL_CORE_DRIVER2;
+
        if (rk29_bl->props.brightness) {
                rk29_bl->props.brightness = 0;
                rk29_bl_update_status(rk29_bl);
                rk29_bl->props.brightness = brightness;
        }
 
-       suspend_flag = 1;
 }
 
 static void rk29_bl_resume(struct early_suspend *h)
@@ -190,7 +211,6 @@ static void rk29_bl_resume(struct early_suspend *h)
        struct rk29_bl_info *rk29_bl_info = bl_get_data(rk29_bl);
        DBG("%s : %s\n", __FILE__, __FUNCTION__);
        
-       suspend_flag = 0;
        schedule_delayed_work(&rk29_backlight_work, msecs_to_jiffies(rk29_bl_info->delay_ms));
 }