C3000背光驱动

最新推荐文章于 2023-07-06 12:05:32 发布

smart_qiang

最新推荐文章于 2023-07-06 12:05:32 发布

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分类专栏： IMX51-android

本文链接：https://blog.youkuaiyun.com/smart_qiang/article/details/19418303

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修改kernel_imx/drivers/video/backlight/pwm_bl.c就行

void lcd_backlight(int level)
{
    unsigned int iPulse;

//   printk(KERN_INFO "lcd_backlight.........qiang.......... .\n");

   if( level < 9 )
         level = 8;
    //turn the 0-255 range to mc13892's duty range 0 -32;
    level = level / 8;

    if (level > 32)
    {
        iPulse = 1;
    }
    else
    {
        iPulse = 32 - level;
    }

    gpio_set_value(GPIO_LCD_BACKLIGHT, 0);
    udelay(2000);

    while(iPulse--)
    {
        gpio_set_value(GPIO_LCD_BACKLIGHT, 1);
        udelay(5);//Jo++ 200 0--Hi == 11 us
        gpio_set_value(GPIO_LCD_BACKLIGHT, 0);
        udelay(5); //Jo++ 200   0--Low == 3 us
    }

   gpio_set_value(GPIO_LCD_BACKLIGHT, 1);
}

static int pwm_backlight_update_status(struct backlight_device *bl)
{
   struct pwm_bl_data *pb = dev_get_drvdata(&bl->dev);
   int brightness = bl->props.brightness;
   int max = bl->props.max_brightness;

   if (bl->props.power != FB_BLANK_UNBLANK)
       brightness = 0;

   if (bl->props.fb_blank != FB_BLANK_UNBLANK)
       brightness = 0;

   if (pb->notify)
       brightness = pb->notify(pb->dev, brightness);

   //add by qiang
//   printk(KERN_INFO "pwm_backlight_update_status.........brightness: %d.......... .\n", brightness);

   lcd_backlight(brightness);
   /*
   if (brightness == 0) {
       pwm_config(pb->pwm, 0, pb->period);
       pwm_disable(pb->pwm);
   } else {
       pwm_config(pb->pwm, brightness * pb->period / max, pb->period);
       pwm_enable(pb->pwm);
   }*/

   return 0;
}