backlight: add step power on support

PD#171081: backlight: add step power on support
default disable with bl_step_on_flag = 0.
change bl_step_on_flag to 1 to enable step_on function:
echo 1 >/sys/class/aml_bl/step_on
the brightness will be level_default first,
then come to the system brightness value.

Change-Id: I47ae56c0f814b2e0e5989b71f151ed84ffee795b
Signed-off-by: Evoke Zhang <evoke.zhang@amlogic.com>

diff --git a/drivers/amlogic/media/vout/backlight/aml_bl.c b/drivers/amlogic/media/vout/backlight/aml_bl.c
index f9d8a2b..5e0e3a0 100644 (file)
--- a/drivers/amlogic/media/vout/backlight/aml_bl.c
+++ b/drivers/amlogic/media/vout/backlight/aml_bl.c
@@ -74,6 +74,7 @@ MODULE_PARM_DESC(brightness_bypass, "bl_brightness_bypass");
 static unsigned char bl_pwm_bypass; /* debug flag */
 static unsigned char bl_pwm_duty_free; /* debug flag */
 static unsigned char bl_on_request; /* for lcd power sequence */
+static unsigned char bl_step_on_flag;
 static unsigned int bl_on_level;
 
 static DEFINE_MUTEX(bl_power_mutex);
@@ -2071,10 +2072,10 @@ static int aml_bl_config_load(struct bl_config_s *bconf,
                ret = aml_bl_config_load_from_dts(bconf, pdev);
 #endif
        }
-       if (bl_level) {
+       if (bl_level)
                bl_level_uboot = bl_level;
-               bconf->level_default = bl_level;
-       }
+       bl_on_level = (bl_level_uboot > 0) ? bl_level_uboot : BL_LEVEL_DEFAULT;
+
        aml_bl_config_print(bconf);
 
 #ifdef CONFIG_AMLOGIC_LOCAL_DIMMING
@@ -2101,6 +2102,23 @@ static int aml_bl_config_load(struct bl_config_s *bconf,
 }
 
 /* lcd notify */
+static void aml_bl_step_on(int brightness)
+{
+       mutex_lock(&bl_level_mutex);
+       BLPR("bl_step_on level: %d\n", brightness);
+
+       if (brightness == 0) {
+               if (bl_drv->state & BL_STATE_BL_ON)
+                       bl_power_off();
+       } else {
+               aml_bl_set_level(brightness);
+               if ((bl_drv->state & BL_STATE_BL_ON) == 0)
+                       bl_power_on();
+       }
+       msleep(120);
+       mutex_unlock(&bl_level_mutex);
+}
+
 static void aml_bl_on_function(void)
 {
        /* lcd power on backlight flag */
@@ -2110,8 +2128,14 @@ static void aml_bl_on_function(void)
        if (brightness_bypass) {
                if ((bl_drv->state & BL_STATE_BL_ON) == 0)
                        bl_power_on();
-       } else
+       } else {
+               if (bl_step_on_flag) {
+                       aml_bl_step_on(bl_drv->bconf->level_default);
+                       BLPR("bl_on level: %d\n",
+                               bl_drv->bldev->props.brightness);
+               }
                aml_bl_update_status(bl_drv->bldev);
+       }
 }
 
 static void aml_bl_delayd_on(struct work_struct *work)
@@ -2336,6 +2360,8 @@ static ssize_t bl_status_read(struct class *class,
                "state:              0x%x\n"
                "level:              %d\n"
                "level_uboot:        %d\n"
+               "level_default:      %d\n"
+               "step_on_flag        %d\n"
                "brightness_bypass:  %d\n\n"
                "level_max:          %d\n"
                "level_min:          %d\n"
@@ -2349,7 +2375,8 @@ static ssize_t bl_status_read(struct class *class,
                "power_off_delay:    %d\n\n",
                bl_key_valid, bl_config_load,
                bl_drv->index, bconf->name, bl_drv->state,
-               bl_drv->level,  bl_level_uboot, brightness_bypass,
+               bl_drv->level,  bl_level_uboot, bconf->level_default,
+               bl_step_on_flag, brightness_bypass,
                bconf->level_max, bconf->level_min,
                bconf->level_mid, bconf->level_mid_mapping,
                bl_method_type_to_str(bconf->method),
@@ -2844,6 +2871,30 @@ static ssize_t bl_debug_power_store(struct class *class,
        return count;
 }
 
+static ssize_t bl_debug_step_on_show(struct class *class,
+               struct class_attribute *attr, char *buf)
+{
+       return sprintf(buf, "backlight step_on: %d\n", bl_step_on_flag);
+}
+
+static ssize_t bl_debug_step_on_store(struct class *class,
+               struct class_attribute *attr, const char *buf, size_t count)
+{
+       unsigned int ret;
+       unsigned int temp = 0;
+
+       ret = kstrtouint(buf, 10, &temp);
+       if (ret != 0) {
+               BLERR("invalid data\n");
+               return -EINVAL;
+       }
+
+       bl_step_on_flag = (unsigned char)temp;
+       BLPR("step_on: %u\n", bl_step_on_flag);
+
+       return count;
+}
+
 static ssize_t bl_debug_delay_show(struct class *class,
                struct class_attribute *attr, char *buf)
 {
@@ -2916,6 +2967,7 @@ static struct class_attribute bl_debug_class_attrs[] = {
        __ATTR(status, 0444, bl_status_read, NULL),
        __ATTR(pwm, 0644, bl_debug_pwm_show, bl_debug_pwm_store),
        __ATTR(power, 0644, bl_debug_power_show, bl_debug_power_store),
+       __ATTR(step_on, 0644, bl_debug_step_on_show, bl_debug_step_on_store),
        __ATTR(delay, 0644, bl_debug_delay_show, bl_debug_delay_store),
        __ATTR(key_valid,   0444, bl_debug_key_valid_show, NULL),
        __ATTR(config_load, 0444, bl_debug_config_load_show, NULL),
@@ -3084,13 +3136,10 @@ static void aml_bl_init_status_update(void)
                        BL_STATE_BL_POWER_ON | BL_STATE_BL_ON);
        bl_on_request = 1;
 
-       if (brightness_bypass) {
-               aml_bl_set_level(bl_level_uboot);
-               bl_on_level = bl_level_uboot;
-       } else {
+       if (brightness_bypass)
+               aml_bl_set_level(bl_on_level);
+       else
                aml_bl_update_status(bl_drv->bldev);
-               bl_on_level = bl_drv->bconf->level_default;
-       }
 }
 
 static int aml_bl_probe(struct platform_device *pdev)
@@ -3113,6 +3162,7 @@ static int aml_bl_probe(struct platform_device *pdev)
        brightness_bypass = 0;
        bl_pwm_bypass = 0;
        bl_pwm_duty_free = 0;
+       bl_step_on_flag = 0;
 
        bl_drv = kzalloc(sizeof(struct aml_bl_drv_s), GFP_KERNEL);
        if (!bl_drv) {
@@ -3141,8 +3191,7 @@ static int aml_bl_probe(struct platform_device *pdev)
        props.power = FB_BLANK_UNBLANK; /* full on */
        props.max_brightness = (bconf->level_max > 0 ?
                        bconf->level_max : BL_LEVEL_MAX);
-       props.brightness = (bconf->level_default > 0 ?
-                       bconf->level_default : BL_LEVEL_DEFAULT);
+       props.brightness = bl_on_level;
 
        bldev = backlight_device_register(AML_BL_NAME, &pdev->dev,
                                        bl_drv, &aml_bl_ops, &props);