drivers/gpu/drm/bridge/lvds-encoder.c

   1 /*
   2  * Copyright (C) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of
   7  * the License, or (at your option) any later version.
   8  */
   9
  10 #include <drm/drmP.h>
  11 #include <drm/drm_atomic_helper.h>
  12 #include <drm/drm_connector.h>
  13 #include <drm/drm_crtc_helper.h>
  14 #include <drm/drm_encoder.h>
  15 #include <drm/drm_modeset_helper_vtables.h>
  16 #include <drm/drm_panel.h>
  17
  18 #include <linux/of_graph.h>
  19
  20 struct lvds_encoder {
  21         struct device *dev;
  22
  23         struct drm_bridge bridge;
  24         struct drm_connector connector;
  25         struct drm_panel *panel;
  26 };
  27
  28 static inline struct lvds_encoder *
  29 drm_bridge_to_lvds_encoder(struct drm_bridge *bridge)
  30 {
  31         return container_of(bridge, struct lvds_encoder, bridge);
  32 }
  33
  34 static inline struct lvds_encoder *
  35 drm_connector_to_lvds_encoder(struct drm_connector *connector)
  36 {
  37         return container_of(connector, struct lvds_encoder, connector);
  38 }
  39
  40 static int lvds_connector_get_modes(struct drm_connector *connector)
  41 {
  42         struct lvds_encoder *lvds = drm_connector_to_lvds_encoder(connector);
  43
  44         return drm_panel_get_modes(lvds->panel);
  45 }
  46
  47 static const struct drm_connector_helper_funcs lvds_connector_helper_funcs = {
  48         .get_modes = lvds_connector_get_modes,
  49 };
  50
  51 static const struct drm_connector_funcs lvds_connector_funcs = {
  52         .dpms = drm_atomic_helper_connector_dpms,
  53         .reset = drm_atomic_helper_connector_reset,
  54         .fill_modes = drm_helper_probe_single_connector_modes,
  55         .destroy = drm_connector_cleanup,
  56         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
  57         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
  58 };
  59
  60 static int lvds_encoder_attach(struct drm_bridge *bridge)
  61 {
  62         struct lvds_encoder *lvds = drm_bridge_to_lvds_encoder(bridge);
  63         struct drm_connector *connector = &lvds->connector;
  64         int ret;
  65
  66         if (!bridge->encoder) {
  67                 DRM_ERROR("Missing encoder\n");
  68                 return -ENODEV;
  69         }
  70
  71         drm_connector_helper_add(connector, &lvds_connector_helper_funcs);
  72
  73         ret = drm_connector_init(bridge->dev, connector, &lvds_connector_funcs,
  74                                  DRM_MODE_CONNECTOR_LVDS);
  75         if (ret) {
  76                 DRM_ERROR("Failed to initialize connector\n");
  77                 return ret;
  78         }
  79
  80         drm_mode_connector_attach_encoder(&lvds->connector, bridge->encoder);
  81
  82         ret = drm_panel_attach(lvds->panel, &lvds->connector);
  83         if (ret < 0)
  84                 return ret;
  85
  86         return 0;
  87 }
  88
  89 static void lvds_encoder_detach(struct drm_bridge *bridge)
  90 {
  91         struct lvds_encoder *lvds = drm_bridge_to_lvds_encoder(bridge);
  92
  93         drm_panel_detach(lvds->panel);
  94 }
  95
  96 static void lvds_encoder_pre_enable(struct drm_bridge *bridge)
  97 {
  98         struct lvds_encoder *lvds = drm_bridge_to_lvds_encoder(bridge);
  99
 100         drm_panel_prepare(lvds->panel);
 101 }
 102
 103 static void lvds_encoder_enable(struct drm_bridge *bridge)
 104 {
 105         struct lvds_encoder *lvds = drm_bridge_to_lvds_encoder(bridge);
 106
 107         drm_panel_enable(lvds->panel);
 108 }
 109
 110 static void lvds_encoder_disable(struct drm_bridge *bridge)
 111 {
 112         struct lvds_encoder *lvds = drm_bridge_to_lvds_encoder(bridge);
 113
 114         drm_panel_disable(lvds->panel);
 115 }
 116
 117 static void lvds_encoder_post_disable(struct drm_bridge *bridge)
 118 {
 119         struct lvds_encoder *lvds = drm_bridge_to_lvds_encoder(bridge);
 120
 121         drm_panel_unprepare(lvds->panel);
 122 }
 123
 124 static const struct drm_bridge_funcs lvds_encoder_bridge_funcs = {
 125         .attach = lvds_encoder_attach,
 126         .detach = lvds_encoder_detach,
 127         .pre_enable = lvds_encoder_pre_enable,
 128         .enable = lvds_encoder_enable,
 129         .disable = lvds_encoder_disable,
 130         .post_disable = lvds_encoder_post_disable,
 131 };
 132
 133 static int lvds_encoder_probe(struct platform_device *pdev)
 134 {
 135         struct lvds_encoder *lvds;
 136         struct device_node *port;
 137         struct device_node *endpoint;
 138         struct device_node *panel;
 139
 140         lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL);
 141         if (!lvds)
 142                 return -ENOMEM;
 143
 144         lvds->dev = &pdev->dev;
 145         platform_set_drvdata(pdev, lvds);
 146
 147         lvds->bridge.funcs = &lvds_encoder_bridge_funcs;
 148         lvds->bridge.of_node = pdev->dev.of_node;
 149
 150         /* Locate the panel DT node. */
 151         port = of_graph_get_port_by_id(pdev->dev.of_node, 1);
 152         if (!port) {
 153                 dev_dbg(&pdev->dev, "port 1 not found\n");
 154                 return -ENXIO;
 155         }
 156
 157         endpoint = of_get_child_by_name(port, "endpoint");
 158         of_node_put(port);
 159         if (!endpoint) {
 160                 dev_dbg(&pdev->dev, "no endpoint for port 1\n");
 161                 return -ENXIO;
 162         }
 163
 164         panel = of_graph_get_remote_port_parent(endpoint);
 165         of_node_put(endpoint);
 166         if (!panel) {
 167                 dev_dbg(&pdev->dev, "no remote endpoint for port 1\n");
 168                 return -ENXIO;
 169         }
 170
 171         lvds->panel = of_drm_find_panel(panel);
 172         of_node_put(panel);
 173         if (!lvds->panel) {
 174                 dev_dbg(&pdev->dev, "panel not found, deferring probe\n");
 175                 return -EPROBE_DEFER;
 176         }
 177
 178         /* Register the bridge. */
 179         return drm_bridge_add(&lvds->bridge);
 180 }
 181
 182 static int lvds_encoder_remove(struct platform_device *pdev)
 183 {
 184         struct lvds_encoder *encoder = platform_get_drvdata(pdev);
 185
 186         drm_bridge_remove(&encoder->bridge);
 187
 188         return 0;
 189 }
 190
 191 static const struct of_device_id lvds_encoder_match[] = {
 192         { .compatible = "lvds-encoder" },
 193         { .compatible = "thine,thc63lvdm83d" },
 194         {},
 195 };
 196 MODULE_DEVICE_TABLE(of, lvds_encoder_match);
 197
 198 static struct platform_driver lvds_encoder_driver = {
 199         .probe  = lvds_encoder_probe,
 200         .remove = lvds_encoder_remove,
 201         .driver         = {
 202                 .name           = "lvds-encoder",
 203                 .of_match_table = lvds_encoder_match,
 204         },
 205 };
 206 module_platform_driver(lvds_encoder_driver);
 207
 208 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
 209 MODULE_DESCRIPTION("Transparent parallel to LVDS encoder");
 210 MODULE_LICENSE("GPL");