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/drm_atomic_helper.h>
   8 #include <drm/drm_bridge.h>
   9 #include <drm/drm_connector.h>
  10 #include <drm/drm_encoder.h>
  11 #include <drm/drm_modeset_helper_vtables.h>
  12 #include <drm/drm_of.h>
  13 #include <drm/drm_panel.h>
  14 #include <drm/drm_print.h>
  15 #include <drm/drm_probe_helper.h>
  16
  17 struct panel_bridge {
  18         struct drm_bridge bridge;
  19         struct drm_connector connector;
  20         struct drm_panel *panel;
  21         u32 connector_type;
  22 };
  23
  24 static inline struct panel_bridge *
  25 drm_bridge_to_panel_bridge(struct drm_bridge *bridge)
  26 {
  27         return container_of(bridge, struct panel_bridge, bridge);
  28 }
  29
  30 static inline struct panel_bridge *
  31 drm_connector_to_panel_bridge(struct drm_connector *connector)
  32 {
  33         return container_of(connector, struct panel_bridge, connector);
  34 }
  35
  36 static int panel_bridge_connector_get_modes(struct drm_connector *connector)
  37 {
  38         struct panel_bridge *panel_bridge =
  39                 drm_connector_to_panel_bridge(connector);
  40
  41         return drm_panel_get_modes(panel_bridge->panel, connector);
  42 }
  43
  44 static const struct drm_connector_helper_funcs
  45 panel_bridge_connector_helper_funcs = {
  46         .get_modes = panel_bridge_connector_get_modes,
  47 };
  48
  49 static const struct drm_connector_funcs panel_bridge_connector_funcs = {
  50         .reset = drm_atomic_helper_connector_reset,
  51         .fill_modes = drm_helper_probe_single_connector_modes,
  52         .destroy = drm_connector_cleanup,
  53         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
  54         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
  55 };
  56
  57 static int panel_bridge_attach(struct drm_bridge *bridge,
  58                                enum drm_bridge_attach_flags flags)
  59 {
  60         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
  61         struct drm_connector *connector = &panel_bridge->connector;
  62         int ret;
  63
  64         if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
  65                 return 0;
  66
  67         if (!bridge->encoder) {
  68                 DRM_ERROR("Missing encoder\n");
  69                 return -ENODEV;
  70         }
  71
  72         drm_connector_helper_add(connector,
  73                                  &panel_bridge_connector_helper_funcs);
  74
  75         ret = drm_connector_init(bridge->dev, connector,
  76                                  &panel_bridge_connector_funcs,
  77                                  panel_bridge->connector_type);
  78         if (ret) {
  79                 DRM_ERROR("Failed to initialize connector\n");
  80                 return ret;
  81         }
  82
  83         drm_connector_attach_encoder(&panel_bridge->connector,
  84                                           bridge->encoder);
  85
  86         if (bridge->dev->registered) {
  87                 if (connector->funcs->reset)
  88                         connector->funcs->reset(connector);
  89                 drm_connector_register(connector);
  90         }
  91
  92         return 0;
  93 }
  94
  95 static void panel_bridge_detach(struct drm_bridge *bridge)
  96 {
  97         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
  98         struct drm_connector *connector = &panel_bridge->connector;
  99
 100         /*
 101          * Cleanup the connector if we know it was initialized.
 102          *
 103          * FIXME: This wouldn't be needed if the panel_bridge structure was
 104          * allocated with drmm_kzalloc(). This might be tricky since the
 105          * drm_device pointer can only be retrieved when the bridge is attached.
 106          */
 107         if (connector->dev)
 108                 drm_connector_cleanup(connector);
 109 }
 110
 111 static void panel_bridge_pre_enable(struct drm_bridge *bridge)
 112 {
 113         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
 114
 115         drm_panel_prepare(panel_bridge->panel);
 116 }
 117
 118 static void panel_bridge_enable(struct drm_bridge *bridge)
 119 {
 120         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
 121
 122         drm_panel_enable(panel_bridge->panel);
 123 }
 124
 125 static void panel_bridge_disable(struct drm_bridge *bridge)
 126 {
 127         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
 128
 129         drm_panel_disable(panel_bridge->panel);
 130 }
 131
 132 static void panel_bridge_post_disable(struct drm_bridge *bridge)
 133 {
 134         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
 135
 136         drm_panel_unprepare(panel_bridge->panel);
 137 }
 138
 139 static int panel_bridge_get_modes(struct drm_bridge *bridge,
 140                                   struct drm_connector *connector)
 141 {
 142         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
 143
 144         return drm_panel_get_modes(panel_bridge->panel, connector);
 145 }
 146
 147 static void panel_bridge_debugfs_init(struct drm_bridge *bridge,
 148                                       struct dentry *root)
 149 {
 150         struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
 151         struct drm_panel *panel = panel_bridge->panel;
 152
 153         root = debugfs_create_dir("panel", root);
 154         if (panel->funcs->debugfs_init)
 155                 panel->funcs->debugfs_init(panel, root);
 156 }
 157
 158 static const struct drm_bridge_funcs panel_bridge_bridge_funcs = {
 159         .attach = panel_bridge_attach,
 160         .detach = panel_bridge_detach,
 161         .pre_enable = panel_bridge_pre_enable,
 162         .enable = panel_bridge_enable,
 163         .disable = panel_bridge_disable,
 164         .post_disable = panel_bridge_post_disable,
 165         .get_modes = panel_bridge_get_modes,
 166         .atomic_reset = drm_atomic_helper_bridge_reset,
 167         .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
 168         .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
 169         .atomic_get_input_bus_fmts = drm_atomic_helper_bridge_propagate_bus_fmt,
 170         .debugfs_init = panel_bridge_debugfs_init,
 171 };
 172
 173 /**
 174  * drm_panel_bridge_add - Creates a &drm_bridge and &drm_connector that
 175  * just calls the appropriate functions from &drm_panel.
 176  *
 177  * @panel: The drm_panel being wrapped.  Must be non-NULL.
 178  *
 179  * For drivers converting from directly using drm_panel: The expected
 180  * usage pattern is that during either encoder module probe or DSI
 181  * host attach, a drm_panel will be looked up through
 182  * drm_of_find_panel_or_bridge().  drm_panel_bridge_add() is used to
 183  * wrap that panel in the new bridge, and the result can then be
 184  * passed to drm_bridge_attach().  The drm_panel_prepare() and related
 185  * functions can be dropped from the encoder driver (they're now
 186  * called by the KMS helpers before calling into the encoder), along
 187  * with connector creation.  When done with the bridge (after
 188  * drm_mode_config_cleanup() if the bridge has already been attached), then
 189  * drm_panel_bridge_remove() to free it.
 190  *
 191  * The connector type is set to @panel->connector_type, which must be set to a
 192  * known type. Calling this function with a panel whose connector type is
 193  * DRM_MODE_CONNECTOR_Unknown will return ERR_PTR(-EINVAL).
 194  *
 195  * See devm_drm_panel_bridge_add() for an automatically managed version of this
 196  * function.
 197  */
 198 struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel)
 199 {
 200         if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
 201                 return ERR_PTR(-EINVAL);
 202
 203         return drm_panel_bridge_add_typed(panel, panel->connector_type);
 204 }
 205 EXPORT_SYMBOL(drm_panel_bridge_add);
 206
 207 /**
 208  * drm_panel_bridge_add_typed - Creates a &drm_bridge and &drm_connector with
 209  * an explicit connector type.
 210  * @panel: The drm_panel being wrapped.  Must be non-NULL.
 211  * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
 212  *
 213  * This is just like drm_panel_bridge_add(), but forces the connector type to
 214  * @connector_type instead of infering it from the panel.
 215  *
 216  * This function is deprecated and should not be used in new drivers. Use
 217  * drm_panel_bridge_add() instead, and fix panel drivers as necessary if they
 218  * don't report a connector type.
 219  */
 220 struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
 221                                               u32 connector_type)
 222 {
 223         struct panel_bridge *panel_bridge;
 224
 225         if (!panel)
 226                 return ERR_PTR(-EINVAL);
 227
 228         panel_bridge = devm_kzalloc(panel->dev, sizeof(*panel_bridge),
 229                                     GFP_KERNEL);
 230         if (!panel_bridge)
 231                 return ERR_PTR(-ENOMEM);
 232
 233         panel_bridge->connector_type = connector_type;
 234         panel_bridge->panel = panel;
 235
 236         panel_bridge->bridge.funcs = &panel_bridge_bridge_funcs;
 237 #ifdef CONFIG_OF
 238         panel_bridge->bridge.of_node = panel->dev->of_node;
 239 #endif
 240         panel_bridge->bridge.ops = DRM_BRIDGE_OP_MODES;
 241         panel_bridge->bridge.type = connector_type;
 242
 243         drm_bridge_add(&panel_bridge->bridge);
 244
 245         return &panel_bridge->bridge;
 246 }
 247 EXPORT_SYMBOL(drm_panel_bridge_add_typed);
 248
 249 /**
 250  * drm_panel_bridge_remove - Unregisters and frees a drm_bridge
 251  * created by drm_panel_bridge_add().
 252  *
 253  * @bridge: The drm_bridge being freed.
 254  */
 255 void drm_panel_bridge_remove(struct drm_bridge *bridge)
 256 {
 257         struct panel_bridge *panel_bridge;
 258
 259         if (!bridge)
 260                 return;
 261
 262         if (bridge->funcs != &panel_bridge_bridge_funcs)
 263                 return;
 264
 265         panel_bridge = drm_bridge_to_panel_bridge(bridge);
 266
 267         drm_bridge_remove(bridge);
 268         devm_kfree(panel_bridge->panel->dev, bridge);
 269 }
 270 EXPORT_SYMBOL(drm_panel_bridge_remove);
 271
 272 static void devm_drm_panel_bridge_release(struct device *dev, void *res)
 273 {
 274         struct drm_bridge **bridge = res;
 275
 276         drm_panel_bridge_remove(*bridge);
 277 }
 278
 279 /**
 280  * devm_drm_panel_bridge_add - Creates a managed &drm_bridge and &drm_connector
 281  * that just calls the appropriate functions from &drm_panel.
 282  * @dev: device to tie the bridge lifetime to
 283  * @panel: The drm_panel being wrapped.  Must be non-NULL.
 284  *
 285  * This is the managed version of drm_panel_bridge_add() which automatically
 286  * calls drm_panel_bridge_remove() when @dev is unbound.
 287  */
 288 struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
 289                                              struct drm_panel *panel)
 290 {
 291         if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
 292                 return ERR_PTR(-EINVAL);
 293
 294         return devm_drm_panel_bridge_add_typed(dev, panel,
 295                                                panel->connector_type);
 296 }
 297 EXPORT_SYMBOL(devm_drm_panel_bridge_add);
 298
 299 /**
 300  * devm_drm_panel_bridge_add_typed - Creates a managed &drm_bridge and
 301  * &drm_connector with an explicit connector type.
 302  * @dev: device to tie the bridge lifetime to
 303  * @panel: The drm_panel being wrapped.  Must be non-NULL.
 304  * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
 305  *
 306  * This is just like devm_drm_panel_bridge_add(), but forces the connector type
 307  * to @connector_type instead of infering it from the panel.
 308  *
 309  * This function is deprecated and should not be used in new drivers. Use
 310  * devm_drm_panel_bridge_add() instead, and fix panel drivers as necessary if
 311  * they don't report a connector type.
 312  */
 313 struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev,
 314                                                    struct drm_panel *panel,
 315                                                    u32 connector_type)
 316 {
 317         struct drm_bridge **ptr, *bridge;
 318
 319         ptr = devres_alloc(devm_drm_panel_bridge_release, sizeof(*ptr),
 320                            GFP_KERNEL);
 321         if (!ptr)
 322                 return ERR_PTR(-ENOMEM);
 323
 324         bridge = drm_panel_bridge_add_typed(panel, connector_type);
 325         if (!IS_ERR(bridge)) {
 326                 *ptr = bridge;
 327                 devres_add(dev, ptr);
 328         } else {
 329                 devres_free(ptr);
 330         }
 331
 332         return bridge;
 333 }
 334 EXPORT_SYMBOL(devm_drm_panel_bridge_add_typed);
 335
 336 /**
 337  * drm_panel_bridge_connector - return the connector for the panel bridge
 338  * @bridge: The drm_bridge.
 339  *
 340  * drm_panel_bridge creates the connector.
 341  * This function gives external access to the connector.
 342  *
 343  * Returns: Pointer to drm_connector
 344  */
 345 struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge)
 346 {
 347         struct panel_bridge *panel_bridge;
 348
 349         panel_bridge = drm_bridge_to_panel_bridge(bridge);
 350
 351         return &panel_bridge->connector;
 352 }
 353 EXPORT_SYMBOL(drm_panel_bridge_connector);
 354
 355 #ifdef CONFIG_OF
 356 /**
 357  * devm_drm_of_get_bridge - Return next bridge in the chain
 358  * @dev: device to tie the bridge lifetime to
 359  * @np: device tree node containing encoder output ports
 360  * @port: port in the device tree node
 361  * @endpoint: endpoint in the device tree node
 362  *
 363  * Given a DT node's port and endpoint number, finds the connected node
 364  * and returns the associated bridge if any, or creates and returns a
 365  * drm panel bridge instance if a panel is connected.
 366  *
 367  * Returns a pointer to the bridge if successful, or an error pointer
 368  * otherwise.
 369  */
 370 struct drm_bridge *devm_drm_of_get_bridge(struct device *dev,
 371                                           struct device_node *np,
 372                                           u32 port, u32 endpoint)
 373 {
 374         struct drm_bridge *bridge;
 375         struct drm_panel *panel;
 376         int ret;
 377
 378         ret = drm_of_find_panel_or_bridge(np, port, endpoint,
 379                                           &panel, &bridge);
 380         if (ret)
 381                 return ERR_PTR(ret);
 382
 383         if (panel)
 384                 bridge = devm_drm_panel_bridge_add(dev, panel);
 385
 386         return bridge;
 387 }
 388 EXPORT_SYMBOL(devm_drm_of_get_bridge);
 389 #endif