LXR linux/include/drm/drm

   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#ifndef __DRM_PANEL_H__
  25#define __DRM_PANEL_H__
  26
  27#include <linux/list.h>
  28
  29struct drm_connector;
  30struct drm_device;
  31struct drm_panel;
  32
  33/**
  34 * struct drm_panel_funcs - perform operations on a given panel
  35 * @disable: disable panel (turn off back light, etc.)
  36 * @unprepare: turn off panel
  37 * @prepare: turn on panel and perform set up
  38 * @enable: enable panel (turn on back light, etc.)
  39 * @get_modes: add modes to the connector that the panel is attached to and
  40 * return the number of modes added
  41 *
  42 * The .prepare() function is typically called before the display controller
  43 * starts to transmit video data. Panel drivers can use this to turn the panel
  44 * on and wait for it to become ready. If additional configuration is required
  45 * (via a control bus such as I2C, SPI or DSI for example) this is a good time
  46 * to do that.
  47 *
  48 * After the display controller has started transmitting video data, it's safe
  49 * to call the .enable() function. This will typically enable the backlight to
  50 * make the image on screen visible. Some panels require a certain amount of
  51 * time or frames before the image is displayed. This function is responsible
  52 * for taking this into account before enabling the backlight to avoid visual
  53 * glitches.
  54 *
  55 * Before stopping video transmission from the display controller it can be
  56 * necessary to turn off the panel to avoid visual glitches. This is done in
  57 * the .disable() function. Analogously to .enable() this typically involves
  58 * turning off the backlight and waiting for some time to make sure no image
  59 * is visible on the panel. It is then safe for the display controller to
  60 * cease transmission of video data.
  61 *
  62 * To save power when no video data is transmitted, a driver can power down
  63 * the panel. This is the job of the .unprepare() function.
  64 */
  65struct drm_panel_funcs {
  66        int (*disable)(struct drm_panel *panel);
  67        int (*unprepare)(struct drm_panel *panel);
  68        int (*prepare)(struct drm_panel *panel);
  69        int (*enable)(struct drm_panel *panel);
  70        int (*get_modes)(struct drm_panel *panel);
  71};
  72
  73struct drm_panel {
  74        struct drm_device *drm;
  75        struct drm_connector *connector;
  76        struct device *dev;
  77
  78        const struct drm_panel_funcs *funcs;
  79
  80        struct list_head list;
  81};
  82
  83static inline int drm_panel_unprepare(struct drm_panel *panel)
  84{
  85        if (panel && panel->funcs && panel->funcs->unprepare)
  86                return panel->funcs->unprepare(panel);
  87
  88        return panel ? -ENOSYS : -EINVAL;
  89}
  90
  91static inline int drm_panel_disable(struct drm_panel *panel)
  92{
  93        if (panel && panel->funcs && panel->funcs->disable)
  94                return panel->funcs->disable(panel);
  95
  96        return panel ? -ENOSYS : -EINVAL;
  97}
  98
  99static inline int drm_panel_prepare(struct drm_panel *panel)
 100{
 101        if (panel && panel->funcs && panel->funcs->prepare)
 102                return panel->funcs->prepare(panel);
 103
 104        return panel ? -ENOSYS : -EINVAL;
 105}
 106
 107static inline int drm_panel_enable(struct drm_panel *panel)
 108{
 109        if (panel && panel->funcs && panel->funcs->enable)
 110                return panel->funcs->enable(panel);
 111
 112        return panel ? -ENOSYS : -EINVAL;
 113}
 114
 115static inline int drm_panel_get_modes(struct drm_panel *panel)
 116{
 117        if (panel && panel->funcs && panel->funcs->get_modes)
 118                return panel->funcs->get_modes(panel);
 119
 120        return panel ? -ENOSYS : -EINVAL;
 121}
 122
 123void drm_panel_init(struct drm_panel *panel);
 124
 125int drm_panel_add(struct drm_panel *panel);
 126void drm_panel_remove(struct drm_panel *panel);
 127
 128int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector);
 129int drm_panel_detach(struct drm_panel *panel);
 130
 131#ifdef CONFIG_OF
 132struct drm_panel *of_drm_find_panel(struct device_node *np);
 133#else
 134static inline struct drm_panel *of_drm_find_panel(struct device_node *np)
 135{
 136        return NULL;
 137}
 138#endif
 139
 140#endif
 141