drivers/video/exynos/exynos_pwm_bl.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * PWM BACKLIGHT driver for Board based on EXYNOS.
   4  *
   5  * Author: Donghwa Lee  <[email protected]>
   6  *
   7  * Derived from linux/drivers/video/backlight/pwm_backlight.c
   8  */
   9
  10 #include <common.h>
  11 #include <pwm.h>
  12 #include <linux/types.h>
  13 #include <asm/io.h>
  14 #include <asm/arch/cpu.h>
  15 #include <asm/arch/gpio.h>
  16 #include <asm/arch/pwm.h>
  17 #include <asm/arch/pwm_backlight.h>
  18
  19 static struct pwm_backlight_data *pwm;
  20
  21 static int exynos_pwm_backlight_update_status(void)
  22 {
  23         int brightness = pwm->brightness;
  24         int max = pwm->max_brightness;
  25
  26         if (brightness == 0) {
  27                 pwm_config(pwm->pwm_id, 0, pwm->period);
  28                 pwm_disable(pwm->pwm_id);
  29         } else {
  30                 pwm_config(pwm->pwm_id,
  31                         brightness * pwm->period / max, pwm->period);
  32                 pwm_enable(pwm->pwm_id);
  33         }
  34         return 0;
  35 }
  36
  37 int exynos_pwm_backlight_init(struct pwm_backlight_data *pd)
  38 {
  39         pwm = pd;
  40
  41         exynos_pwm_backlight_update_status();
  42
  43         return 0;
  44 }