drivers/gpu/drm/bridge/panel.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
   4  * Copyright (C) 2017 Broadcom
   5  */
   6
   7 #include <drm/drmP.h>
   8 #include <drm/drm_panel.h>
   9 #include <drm/drm_atomic_helper.h>
  10 #include <drm/drm_connector.h>
  11 #include <drm/drm_encoder.h>
  12 #include <drm/drm_modeset_helper_vtables.h>
  13 #include <drm/drm_probe_helper.h>
  14 #include <drm/drm_panel.h>
  15
  16 struct panel_bridge {
  17         struct drm_bridge bridge;
  18         struct drm_connector connector;
  19         struct drm_panel *panel;
  20         u32 connector_type;
  21 };
  22
  23 static inline struct panel_bridge *
  24 drm_bridge_to_panel_bridge(struct drm_bridge *bridge)
  25 {
  26         return container_of(bridge, struct panel_bridge, bridge);
  27 }
  28
  29 static inline struct panel_bridge *
  30 drm_connector_to_panel_bridge(struct drm_connector *connector)
  31 {
  32         return container_of(connector, struct panel_bridge, connector);
  33 }
  34
  35 static int panel_bridge_connector_get_modes(struct drm_connector *connector)
  36 {
  37         struct panel_bridge *panel_bridge =
  38                 drm_connector_to_panel_bridge(connector);
  39
  40         return drm_panel_get_modes(panel_bridge->panel);
  41 }
  42
  43 static const struct drm_connector_helper_funcs
  44 panel_bridge_connector_helper_funcs = {
  45         .get_modes = panel_bridge_connector_get_modes,
  46 };
  47
  48 static const struct drm_connector_funcs panel_bridge_connector_funcs = {
  49         .reset = drm_atomic_helper_connector_reset,
  50         .fill_modes = drm_helper_probe_single_connector_modes,
  51         .destroy = drm_connector_cleanup,
  52         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
  53         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
  54 };
  55
  56 static int panel_bridge_attach(struct drm_bridge *bridge)
  57 {
  58         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
  59         struct drm_connector *connector = &panel_bridge->connector;
  60         int ret;
  61
  62         if (!bridge->encoder) {
  63                 DRM_ERROR("Missing encoder\n");
  64                 return -ENODEV;
  65         }
  66
  67         drm_connector_helper_add(connector,
  68                                  &panel_bridge_connector_helper_funcs);
  69
  70         ret = drm_connector_init(bridge->dev, connector,
  71                                  &panel_bridge_connector_funcs,
  72                                  panel_bridge->connector_type);
  73         if (ret) {
  74                 DRM_ERROR("Failed to initialize connector\n");
  75                 return ret;
  76         }
  77
  78         drm_connector_attach_encoder(&panel_bridge->connector,
  79                                           bridge->encoder);
  80
  81         ret = drm_panel_attach(panel_bridge->panel, &panel_bridge->connector);
  82         if (ret < 0)
  83                 return ret;
  84
  85         return 0;
  86 }
  87
  88 static void panel_bridge_detach(struct drm_bridge *bridge)
  89 {
  90         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
  91
  92         drm_panel_detach(panel_bridge->panel);
  93 }
  94
  95 static void panel_bridge_pre_enable(struct drm_bridge *bridge)
  96 {
  97         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
  98
  99         drm_panel_prepare(panel_bridge->panel);
 100 }
 101
 102 static void panel_bridge_enable(struct drm_bridge *bridge)
 103 {
 104         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
 105
 106         drm_panel_enable(panel_bridge->panel);
 107 }
 108
 109 static void panel_bridge_disable(struct drm_bridge *bridge)
 110 {
 111         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
 112
 113         drm_panel_disable(panel_bridge->panel);
 114 }
 115
 116 static void panel_bridge_post_disable(struct drm_bridge *bridge)
 117 {
 118         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
 119
 120         drm_panel_unprepare(panel_bridge->panel);
 121 }
 122
 123 static const struct drm_bridge_funcs panel_bridge_bridge_funcs = {
 124         .attach = panel_bridge_attach,
 125         .detach = panel_bridge_detach,
 126         .pre_enable = panel_bridge_pre_enable,
 127         .enable = panel_bridge_enable,
 128         .disable = panel_bridge_disable,
 129         .post_disable = panel_bridge_post_disable,
 130 };
 131
 132 /**
 133  * drm_panel_bridge_add - Creates a &drm_bridge and &drm_connector that
 134  * just calls the appropriate functions from &drm_panel.
 135  *
 136  * @panel: The drm_panel being wrapped.  Must be non-NULL.
 137  * @connector_type: The DRM_MODE_CONNECTOR_* for the connector to be
 138  * created.
 139  *
 140  * For drivers converting from directly using drm_panel: The expected
 141  * usage pattern is that during either encoder module probe or DSI
 142  * host attach, a drm_panel will be looked up through
 143  * drm_of_find_panel_or_bridge().  drm_panel_bridge_add() is used to
 144  * wrap that panel in the new bridge, and the result can then be
 145  * passed to drm_bridge_attach().  The drm_panel_prepare() and related
 146  * functions can be dropped from the encoder driver (they're now
 147  * called by the KMS helpers before calling into the encoder), along
 148  * with connector creation.  When done with the bridge (after
 149  * drm_mode_config_cleanup() if the bridge has already been attached), then
 150  * drm_panel_bridge_remove() to free it.
 151  *
 152  * See devm_drm_panel_bridge_add() for an automatically manged version of this
 153  * function.
 154  */
 155 struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel,
 156                                         u32 connector_type)
 157 {
 158         struct panel_bridge *panel_bridge;
 159
 160         if (!panel)
 161                 return ERR_PTR(-EINVAL);
 162
 163         panel_bridge = devm_kzalloc(panel->dev, sizeof(*panel_bridge),
 164                                     GFP_KERNEL);
 165         if (!panel_bridge)
 166                 return ERR_PTR(-ENOMEM);
 167
 168         panel_bridge->connector_type = connector_type;
 169         panel_bridge->panel = panel;
 170
 171         panel_bridge->bridge.funcs = &panel_bridge_bridge_funcs;
 172 #ifdef CONFIG_OF
 173         panel_bridge->bridge.of_node = panel->dev->of_node;
 174 #endif
 175
 176         drm_bridge_add(&panel_bridge->bridge);
 177
 178         return &panel_bridge->bridge;
 179 }
 180 EXPORT_SYMBOL(drm_panel_bridge_add);
 181
 182 /**
 183  * drm_panel_bridge_remove - Unregisters and frees a drm_bridge
 184  * created by drm_panel_bridge_add().
 185  *
 186  * @bridge: The drm_bridge being freed.
 187  */
 188 void drm_panel_bridge_remove(struct drm_bridge *bridge)
 189 {
 190         struct panel_bridge *panel_bridge;
 191
 192         if (!bridge)
 193                 return;
 194
 195         if (bridge->funcs != &panel_bridge_bridge_funcs)
 196                 return;
 197
 198         panel_bridge = drm_bridge_to_panel_bridge(bridge);
 199
 200         drm_bridge_remove(bridge);
 201         devm_kfree(panel_bridge->panel->dev, bridge);
 202 }
 203 EXPORT_SYMBOL(drm_panel_bridge_remove);
 204
 205 static void devm_drm_panel_bridge_release(struct device *dev, void *res)
 206 {
 207         struct drm_bridge **bridge = res;
 208
 209         drm_panel_bridge_remove(*bridge);
 210 }
 211
 212 /**
 213  * devm_drm_panel_bridge_add - Creates a managed &drm_bridge and &drm_connector
 214  * that just calls the appropriate functions from &drm_panel.
 215  * @dev: device to tie the bridge lifetime to
 216  * @panel: The drm_panel being wrapped.  Must be non-NULL.
 217  * @connector_type: The DRM_MODE_CONNECTOR_* for the connector to be
 218  * created.
 219  *
 220  * This is the managed version of drm_panel_bridge_add() which automatically
 221  * calls drm_panel_bridge_remove() when @dev is unbound.
 222  */
 223 struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
 224                                              struct drm_panel *panel,
 225                                              u32 connector_type)
 226 {
 227         struct drm_bridge **ptr, *bridge;
 228
 229         ptr = devres_alloc(devm_drm_panel_bridge_release, sizeof(*ptr),
 230                            GFP_KERNEL);
 231         if (!ptr)
 232                 return ERR_PTR(-ENOMEM);
 233
 234         bridge = drm_panel_bridge_add(panel, connector_type);
 235         if (!IS_ERR(bridge)) {
 236                 *ptr = bridge;
 237                 devres_add(dev, ptr);
 238         } else {
 239                 devres_free(ptr);
 240         }
 241
 242         return bridge;
 243 }
 244 EXPORT_SYMBOL(devm_drm_panel_bridge_add);