drivers/gpu/drm/drm_panel.c

   1 /*
   2  * Copyright (C) 2013, NVIDIA Corporation.  All rights reserved.
   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 #include <drm/drm_panel.h>
  29
  30 static DEFINE_MUTEX(panel_lock);
  31 static LIST_HEAD(panel_list);
  32
  33 void drm_panel_init(struct drm_panel *panel)
  34 {
  35         INIT_LIST_HEAD(&panel->list);
  36 }
  37 EXPORT_SYMBOL(drm_panel_init);
  38
  39 int drm_panel_add(struct drm_panel *panel)
  40 {
  41         mutex_lock(&panel_lock);
  42         list_add_tail(&panel->list, &panel_list);
  43         mutex_unlock(&panel_lock);
  44
  45         return 0;
  46 }
  47 EXPORT_SYMBOL(drm_panel_add);
  48
  49 void drm_panel_remove(struct drm_panel *panel)
  50 {
  51         mutex_lock(&panel_lock);
  52         list_del_init(&panel->list);
  53         mutex_unlock(&panel_lock);
  54 }
  55 EXPORT_SYMBOL(drm_panel_remove);
  56
  57 int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector)
  58 {
  59         if (panel->connector)
  60                 return -EBUSY;
  61
  62         panel->connector = connector;
  63         panel->drm = connector->dev;
  64
  65         return 0;
  66 }
  67 EXPORT_SYMBOL(drm_panel_attach);
  68
  69 int drm_panel_detach(struct drm_panel *panel)
  70 {
  71         panel->connector = NULL;
  72         panel->drm = NULL;
  73
  74         return 0;
  75 }
  76 EXPORT_SYMBOL(drm_panel_detach);
  77
  78 #ifdef CONFIG_OF
  79 struct drm_panel *of_drm_find_panel(struct device_node *np)
  80 {
  81         struct drm_panel *panel;
  82
  83         mutex_lock(&panel_lock);
  84
  85         list_for_each_entry(panel, &panel_list, list) {
  86                 if (panel->dev->of_node == np) {
  87                         mutex_unlock(&panel_lock);
  88                         return panel;
  89                 }
  90         }
  91
  92         mutex_unlock(&panel_lock);
  93         return NULL;
  94 }
  95 EXPORT_SYMBOL(of_drm_find_panel);
  96 #endif
  97
  98 MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
  99 MODULE_DESCRIPTION("DRM panel infrastructure");
 100 MODULE_LICENSE("GPL and additional rights");