drivers/gpu/drm/shmobile/shmob_drm_backlight.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * shmob_drm_backlight.c  --  SH Mobile DRM Backlight
   4  *
   5  * Copyright (C) 2012 Renesas Electronics Corporation
   6  *
   7  * Laurent Pinchart ([email protected])
   8  */
   9
  10 #include <linux/backlight.h>
  11
  12 #include "shmob_drm_backlight.h"
  13 #include "shmob_drm_crtc.h"
  14 #include "shmob_drm_drv.h"
  15
  16 static int shmob_drm_backlight_update(struct backlight_device *bdev)
  17 {
  18         struct shmob_drm_connector *scon = bl_get_data(bdev);
  19         struct shmob_drm_device *sdev = scon->connector.dev->dev_private;
  20         const struct shmob_drm_backlight_data *bdata = &sdev->pdata->backlight;
  21         int brightness = backlight_get_brightness(bdev);
  22
  23         return bdata->set_brightness(brightness);
  24 }
  25
  26 static int shmob_drm_backlight_get_brightness(struct backlight_device *bdev)
  27 {
  28         struct shmob_drm_connector *scon = bl_get_data(bdev);
  29         struct shmob_drm_device *sdev = scon->connector.dev->dev_private;
  30         const struct shmob_drm_backlight_data *bdata = &sdev->pdata->backlight;
  31
  32         return bdata->get_brightness();
  33 }
  34
  35 static const struct backlight_ops shmob_drm_backlight_ops = {
  36         .options        = BL_CORE_SUSPENDRESUME,
  37         .update_status  = shmob_drm_backlight_update,
  38         .get_brightness = shmob_drm_backlight_get_brightness,
  39 };
  40
  41 void shmob_drm_backlight_dpms(struct shmob_drm_connector *scon, int mode)
  42 {
  43         if (scon->backlight == NULL)
  44                 return;
  45
  46         scon->backlight->props.power = mode == DRM_MODE_DPMS_ON
  47                                      ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
  48         backlight_update_status(scon->backlight);
  49 }
  50
  51 int shmob_drm_backlight_init(struct shmob_drm_connector *scon)
  52 {
  53         struct shmob_drm_device *sdev = scon->connector.dev->dev_private;
  54         const struct shmob_drm_backlight_data *bdata = &sdev->pdata->backlight;
  55         struct drm_connector *connector = &scon->connector;
  56         struct drm_device *dev = connector->dev;
  57         struct backlight_device *backlight;
  58
  59         if (!bdata->max_brightness)
  60                 return 0;
  61
  62         backlight = backlight_device_register(bdata->name, dev->dev, scon,
  63                                               &shmob_drm_backlight_ops, NULL);
  64         if (IS_ERR(backlight)) {
  65                 dev_err(dev->dev, "unable to register backlight device: %ld\n",
  66                         PTR_ERR(backlight));
  67                 return PTR_ERR(backlight);
  68         }
  69
  70         backlight->props.max_brightness = bdata->max_brightness;
  71         backlight->props.brightness = bdata->max_brightness;
  72         backlight->props.power = FB_BLANK_POWERDOWN;
  73         backlight_update_status(backlight);
  74
  75         scon->backlight = backlight;
  76         return 0;
  77 }
  78
  79 void shmob_drm_backlight_exit(struct shmob_drm_connector *scon)
  80 {
  81         backlight_device_unregister(scon->backlight);
  82 }