drivers/gpu/drm/drm_bridge.c

   1 /*
   2  * Copyright (c) 2014 Samsung Electronics Co., Ltd
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sub license,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the
  12  * next paragraph) shall be included in all copies or substantial portions
  13  * of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 #include <linux/err.h>
  25 #include <linux/module.h>
  26
  27 #include <drm/drm_crtc.h>
  28
  29 #include "drm/drmP.h"
  30
  31 static DEFINE_MUTEX(bridge_lock);
  32 static LIST_HEAD(bridge_list);
  33
  34 int drm_bridge_add(struct drm_bridge *bridge)
  35 {
  36         mutex_lock(&bridge_lock);
  37         list_add_tail(&bridge->list, &bridge_list);
  38         mutex_unlock(&bridge_lock);
  39
  40         return 0;
  41 }
  42 EXPORT_SYMBOL(drm_bridge_add);
  43
  44 void drm_bridge_remove(struct drm_bridge *bridge)
  45 {
  46         mutex_lock(&bridge_lock);
  47         list_del_init(&bridge->list);
  48         mutex_unlock(&bridge_lock);
  49 }
  50 EXPORT_SYMBOL(drm_bridge_remove);
  51
  52 int drm_bridge_attach(struct drm_device *dev, struct drm_bridge *bridge)
  53 {
  54         if (!dev || !bridge)
  55                 return -EINVAL;
  56
  57         if (bridge->dev)
  58                 return -EBUSY;
  59
  60         bridge->dev = dev;
  61
  62         if (bridge->funcs->attach)
  63                 return bridge->funcs->attach(bridge);
  64
  65         return 0;
  66 }
  67 EXPORT_SYMBOL(drm_bridge_attach);
  68
  69 /**
  70  * drm_bridge_mode_fixup - fixup proposed mode for all bridges in the
  71  *                         encoder chain
  72  * @bridge: bridge control structure
  73  * @mode: desired mode to be set for the bridge
  74  * @adjusted_mode: updated mode that works for this bridge
  75  *
  76  * Calls 'mode_fixup' drm_bridge_funcs op for all the bridges in the
  77  * encoder chain, starting from the first bridge to the last.
  78  *
  79  * Note: the bridge passed should be the one closest to the encoder
  80  *
  81  * RETURNS:
  82  * true on success, false on failure
  83  */
  84 bool drm_bridge_mode_fixup(struct drm_bridge *bridge,
  85                         const struct drm_display_mode *mode,
  86                         struct drm_display_mode *adjusted_mode)
  87 {
  88         bool ret = true;
  89
  90         if (!bridge)
  91                 return true;
  92
  93         if (bridge->funcs->mode_fixup)
  94                 ret = bridge->funcs->mode_fixup(bridge, mode, adjusted_mode);
  95
  96         ret = ret && drm_bridge_mode_fixup(bridge->next, mode, adjusted_mode);
  97
  98         return ret;
  99 }
 100 EXPORT_SYMBOL(drm_bridge_mode_fixup);
 101
 102 /**
 103  * drm_bridge_disable - calls 'disable' drm_bridge_funcs op for all
 104  *                      bridges in the encoder chain.
 105  * @bridge: bridge control structure
 106  *
 107  * Calls 'disable' drm_bridge_funcs op for all the bridges in the encoder
 108  * chain, starting from the last bridge to the first. These are called before
 109  * calling the encoder's prepare op.
 110  *
 111  * Note: the bridge passed should be the one closest to the encoder
 112  */
 113 void drm_bridge_disable(struct drm_bridge *bridge)
 114 {
 115         if (!bridge)
 116                 return;
 117
 118         drm_bridge_disable(bridge->next);
 119
 120         bridge->funcs->disable(bridge);
 121 }
 122 EXPORT_SYMBOL(drm_bridge_disable);
 123
 124 /**
 125  * drm_bridge_post_disable - calls 'post_disable' drm_bridge_funcs op for
 126  *                           all bridges in the encoder chain.
 127  * @bridge: bridge control structure
 128  *
 129  * Calls 'post_disable' drm_bridge_funcs op for all the bridges in the
 130  * encoder chain, starting from the first bridge to the last. These are called
 131  * after completing the encoder's prepare op.
 132  *
 133  * Note: the bridge passed should be the one closest to the encoder
 134  */
 135 void drm_bridge_post_disable(struct drm_bridge *bridge)
 136 {
 137         if (!bridge)
 138                 return;
 139
 140         bridge->funcs->post_disable(bridge);
 141
 142         drm_bridge_post_disable(bridge->next);
 143 }
 144 EXPORT_SYMBOL(drm_bridge_post_disable);
 145
 146 /**
 147  * drm_bridge_mode_set - set proposed mode for all bridges in the
 148  *                       encoder chain
 149  * @bridge: bridge control structure
 150  * @mode: desired mode to be set for the bridge
 151  * @adjusted_mode: updated mode that works for this bridge
 152  *
 153  * Calls 'mode_set' drm_bridge_funcs op for all the bridges in the
 154  * encoder chain, starting from the first bridge to the last.
 155  *
 156  * Note: the bridge passed should be the one closest to the encoder
 157  */
 158 void drm_bridge_mode_set(struct drm_bridge *bridge,
 159                         struct drm_display_mode *mode,
 160                         struct drm_display_mode *adjusted_mode)
 161 {
 162         if (!bridge)
 163                 return;
 164
 165         if (bridge->funcs->mode_set)
 166                 bridge->funcs->mode_set(bridge, mode, adjusted_mode);
 167
 168         drm_bridge_mode_set(bridge->next, mode, adjusted_mode);
 169 }
 170 EXPORT_SYMBOL(drm_bridge_mode_set);
 171
 172 /**
 173  * drm_bridge_pre_enable - calls 'pre_enable' drm_bridge_funcs op for all
 174  *                         bridges in the encoder chain.
 175  * @bridge: bridge control structure
 176  *
 177  * Calls 'pre_enable' drm_bridge_funcs op for all the bridges in the encoder
 178  * chain, starting from the last bridge to the first. These are called
 179  * before calling the encoder's commit op.
 180  *
 181  * Note: the bridge passed should be the one closest to the encoder
 182  */
 183 void drm_bridge_pre_enable(struct drm_bridge *bridge)
 184 {
 185         if (!bridge)
 186                 return;
 187
 188         drm_bridge_pre_enable(bridge->next);
 189
 190         bridge->funcs->pre_enable(bridge);
 191 }
 192 EXPORT_SYMBOL(drm_bridge_pre_enable);
 193
 194 /**
 195  * drm_bridge_enable - calls 'enable' drm_bridge_funcs op for all bridges
 196  *                     in the encoder chain.
 197  * @bridge: bridge control structure
 198  *
 199  * Calls 'enable' drm_bridge_funcs op for all the bridges in the encoder
 200  * chain, starting from the first bridge to the last. These are called
 201  * after completing the encoder's commit op.
 202  *
 203  * Note that the bridge passed should be the one closest to the encoder
 204  */
 205 void drm_bridge_enable(struct drm_bridge *bridge)
 206 {
 207         if (!bridge)
 208                 return;
 209
 210         bridge->funcs->enable(bridge);
 211
 212         drm_bridge_enable(bridge->next);
 213 }
 214 EXPORT_SYMBOL(drm_bridge_enable);
 215
 216 #ifdef CONFIG_OF
 217 struct drm_bridge *of_drm_find_bridge(struct device_node *np)
 218 {
 219         struct drm_bridge *bridge;
 220
 221         mutex_lock(&bridge_lock);
 222
 223         list_for_each_entry(bridge, &bridge_list, list) {
 224                 if (bridge->of_node == np) {
 225                         mutex_unlock(&bridge_lock);
 226                         return bridge;
 227                 }
 228         }
 229
 230         mutex_unlock(&bridge_lock);
 231         return NULL;
 232 }
 233 EXPORT_SYMBOL(of_drm_find_bridge);
 234 #endif
 235
 236 MODULE_AUTHOR("Ajay Kumar <ajaykumar.rs@samsung.com>");
 237 MODULE_DESCRIPTION("DRM bridge infrastructure");
 238 MODULE_LICENSE("GPL and additional rights");