1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * GMA500 Backlight Interface 4 * 5 * Copyright (c) 2009-2011, Intel Corporation. 6 * 7 * Authors: Eric Knopp 8 */ 9 10 #include <acpi/video.h> 11 12 #include "psb_drv.h" 13 #include "psb_intel_reg.h" 14 #include "psb_intel_drv.h" 15 #include "intel_bios.h" 16 #include "power.h" 17 18 void gma_backlight_enable(struct drm_device *dev) 19 { 20 struct drm_psb_private *dev_priv = to_drm_psb_private(dev); 21 22 dev_priv->backlight_enabled = true; 23 dev_priv->ops->backlight_set(dev, dev_priv->backlight_level); 24 } 25 26 void gma_backlight_disable(struct drm_device *dev) 27 { 28 struct drm_psb_private *dev_priv = to_drm_psb_private(dev); 29 30 dev_priv->backlight_enabled = false; 31 dev_priv->ops->backlight_set(dev, 0); 32 } 33 34 void gma_backlight_set(struct drm_device *dev, int v) 35 { 36 struct drm_psb_private *dev_priv = to_drm_psb_private(dev); 37 38 dev_priv->backlight_level = v; 39 if (dev_priv->backlight_enabled) 40 dev_priv->ops->backlight_set(dev, v); 41 } 42 43 static int gma_backlight_get_brightness(struct backlight_device *bd) 44 { 45 struct drm_device *dev = bl_get_data(bd); 46 struct drm_psb_private *dev_priv = to_drm_psb_private(dev); 47 48 if (dev_priv->ops->backlight_get) 49 return dev_priv->ops->backlight_get(dev); 50 51 return dev_priv->backlight_level; 52 } 53 54 static int gma_backlight_update_status(struct backlight_device *bd) 55 { 56 struct drm_device *dev = bl_get_data(bd); 57 int level = backlight_get_brightness(bd); 58 59 /* Percentage 1-100% being valid */ 60 if (level < 1) 61 level = 1; 62 63 gma_backlight_set(dev, level); 64 return 0; 65 } 66 67 static const struct backlight_ops gma_backlight_ops __maybe_unused = { 68 .get_brightness = gma_backlight_get_brightness, 69 .update_status = gma_backlight_update_status, 70 }; 71 72 int gma_backlight_init(struct drm_device *dev) 73 { 74 struct drm_psb_private *dev_priv = to_drm_psb_private(dev); 75 struct backlight_properties props __maybe_unused = {}; 76 int ret; 77 78 dev_priv->backlight_enabled = true; 79 dev_priv->backlight_level = 100; 80 81 ret = dev_priv->ops->backlight_init(dev); 82 if (ret) 83 return ret; 84 85 if (!acpi_video_backlight_use_native()) { 86 drm_info(dev, "Skipping %s backlight registration\n", 87 dev_priv->ops->backlight_name); 88 return 0; 89 } 90 91 #ifdef CONFIG_BACKLIGHT_CLASS_DEVICE 92 props.brightness = dev_priv->backlight_level; 93 props.max_brightness = PSB_MAX_BRIGHTNESS; 94 props.type = BACKLIGHT_RAW; 95 96 dev_priv->backlight_device = 97 backlight_device_register(dev_priv->ops->backlight_name, 98 dev->dev, dev, 99 &gma_backlight_ops, &props); 100 if (IS_ERR(dev_priv->backlight_device)) 101 return PTR_ERR(dev_priv->backlight_device); 102 #endif 103 104 return 0; 105 } 106 107 void gma_backlight_exit(struct drm_device *dev) 108 { 109 #ifdef CONFIG_BACKLIGHT_CLASS_DEVICE 110 struct drm_psb_private *dev_priv = to_drm_psb_private(dev); 111 112 if (dev_priv->backlight_device) 113 backlight_device_unregister(dev_priv->backlight_device); 114 #endif 115 } 116