xref: /linux/drivers/gpu/drm/bridge/panel.c (revision b37042b2bb7cd751f03b73afb90364a418d870f4)
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_bridge_is_panel - Checks if a drm_bridge is a panel_bridge.
175  *
176  * @bridge: The drm_bridge to be checked.
177  *
178  * Returns true if the bridge is a panel bridge, or false otherwise.
179  */
180 bool drm_bridge_is_panel(const struct drm_bridge *bridge)
181 {
182 	return bridge->funcs == &panel_bridge_bridge_funcs;
183 }
184 EXPORT_SYMBOL(drm_bridge_is_panel);
185 
186 /**
187  * drm_panel_bridge_add - Creates a &drm_bridge and &drm_connector that
188  * just calls the appropriate functions from &drm_panel.
189  *
190  * @panel: The drm_panel being wrapped.  Must be non-NULL.
191  *
192  * For drivers converting from directly using drm_panel: The expected
193  * usage pattern is that during either encoder module probe or DSI
194  * host attach, a drm_panel will be looked up through
195  * drm_of_find_panel_or_bridge().  drm_panel_bridge_add() is used to
196  * wrap that panel in the new bridge, and the result can then be
197  * passed to drm_bridge_attach().  The drm_panel_prepare() and related
198  * functions can be dropped from the encoder driver (they're now
199  * called by the KMS helpers before calling into the encoder), along
200  * with connector creation.  When done with the bridge (after
201  * drm_mode_config_cleanup() if the bridge has already been attached), then
202  * drm_panel_bridge_remove() to free it.
203  *
204  * The connector type is set to @panel->connector_type, which must be set to a
205  * known type. Calling this function with a panel whose connector type is
206  * DRM_MODE_CONNECTOR_Unknown will return ERR_PTR(-EINVAL).
207  *
208  * See devm_drm_panel_bridge_add() for an automatically managed version of this
209  * function.
210  */
211 struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel)
212 {
213 	if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
214 		return ERR_PTR(-EINVAL);
215 
216 	return drm_panel_bridge_add_typed(panel, panel->connector_type);
217 }
218 EXPORT_SYMBOL(drm_panel_bridge_add);
219 
220 /**
221  * drm_panel_bridge_add_typed - Creates a &drm_bridge and &drm_connector with
222  * an explicit connector type.
223  * @panel: The drm_panel being wrapped.  Must be non-NULL.
224  * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
225  *
226  * This is just like drm_panel_bridge_add(), but forces the connector type to
227  * @connector_type instead of infering it from the panel.
228  *
229  * This function is deprecated and should not be used in new drivers. Use
230  * drm_panel_bridge_add() instead, and fix panel drivers as necessary if they
231  * don't report a connector type.
232  */
233 struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
234 					      u32 connector_type)
235 {
236 	struct panel_bridge *panel_bridge;
237 
238 	if (!panel)
239 		return ERR_PTR(-EINVAL);
240 
241 	panel_bridge = devm_kzalloc(panel->dev, sizeof(*panel_bridge),
242 				    GFP_KERNEL);
243 	if (!panel_bridge)
244 		return ERR_PTR(-ENOMEM);
245 
246 	panel_bridge->connector_type = connector_type;
247 	panel_bridge->panel = panel;
248 
249 	panel_bridge->bridge.funcs = &panel_bridge_bridge_funcs;
250 #ifdef CONFIG_OF
251 	panel_bridge->bridge.of_node = panel->dev->of_node;
252 #endif
253 	panel_bridge->bridge.ops = DRM_BRIDGE_OP_MODES;
254 	panel_bridge->bridge.type = connector_type;
255 
256 	drm_bridge_add(&panel_bridge->bridge);
257 
258 	return &panel_bridge->bridge;
259 }
260 EXPORT_SYMBOL(drm_panel_bridge_add_typed);
261 
262 /**
263  * drm_panel_bridge_remove - Unregisters and frees a drm_bridge
264  * created by drm_panel_bridge_add().
265  *
266  * @bridge: The drm_bridge being freed.
267  */
268 void drm_panel_bridge_remove(struct drm_bridge *bridge)
269 {
270 	struct panel_bridge *panel_bridge;
271 
272 	if (!bridge)
273 		return;
274 
275 	if (bridge->funcs != &panel_bridge_bridge_funcs)
276 		return;
277 
278 	panel_bridge = drm_bridge_to_panel_bridge(bridge);
279 
280 	drm_bridge_remove(bridge);
281 	devm_kfree(panel_bridge->panel->dev, bridge);
282 }
283 EXPORT_SYMBOL(drm_panel_bridge_remove);
284 
285 /**
286  * drm_panel_bridge_set_orientation - Set the connector's panel orientation
287  * from the bridge that can be transformed to panel bridge.
288  *
289  * @connector: The connector to be set panel orientation.
290  * @bridge: The drm_bridge to be transformed to panel bridge.
291  *
292  * Returns 0 on success, negative errno on failure.
293  */
294 int drm_panel_bridge_set_orientation(struct drm_connector *connector,
295 				     struct drm_bridge *bridge)
296 {
297 	struct panel_bridge *panel_bridge;
298 
299 	panel_bridge = drm_bridge_to_panel_bridge(bridge);
300 
301 	return drm_connector_set_orientation_from_panel(connector,
302 							panel_bridge->panel);
303 }
304 EXPORT_SYMBOL(drm_panel_bridge_set_orientation);
305 
306 static void devm_drm_panel_bridge_release(struct device *dev, void *res)
307 {
308 	struct drm_bridge **bridge = res;
309 
310 	drm_panel_bridge_remove(*bridge);
311 }
312 
313 /**
314  * devm_drm_panel_bridge_add - Creates a managed &drm_bridge and &drm_connector
315  * that just calls the appropriate functions from &drm_panel.
316  * @dev: device to tie the bridge lifetime to
317  * @panel: The drm_panel being wrapped.  Must be non-NULL.
318  *
319  * This is the managed version of drm_panel_bridge_add() which automatically
320  * calls drm_panel_bridge_remove() when @dev is unbound.
321  */
322 struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
323 					     struct drm_panel *panel)
324 {
325 	if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
326 		return ERR_PTR(-EINVAL);
327 
328 	return devm_drm_panel_bridge_add_typed(dev, panel,
329 					       panel->connector_type);
330 }
331 EXPORT_SYMBOL(devm_drm_panel_bridge_add);
332 
333 /**
334  * devm_drm_panel_bridge_add_typed - Creates a managed &drm_bridge and
335  * &drm_connector with an explicit connector type.
336  * @dev: device to tie the bridge lifetime to
337  * @panel: The drm_panel being wrapped.  Must be non-NULL.
338  * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
339  *
340  * This is just like devm_drm_panel_bridge_add(), but forces the connector type
341  * to @connector_type instead of infering it from the panel.
342  *
343  * This function is deprecated and should not be used in new drivers. Use
344  * devm_drm_panel_bridge_add() instead, and fix panel drivers as necessary if
345  * they don't report a connector type.
346  */
347 struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev,
348 						   struct drm_panel *panel,
349 						   u32 connector_type)
350 {
351 	struct drm_bridge **ptr, *bridge;
352 
353 	ptr = devres_alloc(devm_drm_panel_bridge_release, sizeof(*ptr),
354 			   GFP_KERNEL);
355 	if (!ptr)
356 		return ERR_PTR(-ENOMEM);
357 
358 	bridge = drm_panel_bridge_add_typed(panel, connector_type);
359 	if (!IS_ERR(bridge)) {
360 		*ptr = bridge;
361 		devres_add(dev, ptr);
362 	} else {
363 		devres_free(ptr);
364 	}
365 
366 	return bridge;
367 }
368 EXPORT_SYMBOL(devm_drm_panel_bridge_add_typed);
369 
370 /**
371  * drm_panel_bridge_connector - return the connector for the panel bridge
372  * @bridge: The drm_bridge.
373  *
374  * drm_panel_bridge creates the connector.
375  * This function gives external access to the connector.
376  *
377  * Returns: Pointer to drm_connector
378  */
379 struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge)
380 {
381 	struct panel_bridge *panel_bridge;
382 
383 	panel_bridge = drm_bridge_to_panel_bridge(bridge);
384 
385 	return &panel_bridge->connector;
386 }
387 EXPORT_SYMBOL(drm_panel_bridge_connector);
388 
389 #ifdef CONFIG_OF
390 /**
391  * devm_drm_of_get_bridge - Return next bridge in the chain
392  * @dev: device to tie the bridge lifetime to
393  * @np: device tree node containing encoder output ports
394  * @port: port in the device tree node
395  * @endpoint: endpoint in the device tree node
396  *
397  * Given a DT node's port and endpoint number, finds the connected node
398  * and returns the associated bridge if any, or creates and returns a
399  * drm panel bridge instance if a panel is connected.
400  *
401  * Returns a pointer to the bridge if successful, or an error pointer
402  * otherwise.
403  */
404 struct drm_bridge *devm_drm_of_get_bridge(struct device *dev,
405 					  struct device_node *np,
406 					  u32 port, u32 endpoint)
407 {
408 	struct drm_bridge *bridge;
409 	struct drm_panel *panel;
410 	int ret;
411 
412 	ret = drm_of_find_panel_or_bridge(np, port, endpoint,
413 					  &panel, &bridge);
414 	if (ret)
415 		return ERR_PTR(ret);
416 
417 	if (panel)
418 		bridge = devm_drm_panel_bridge_add(dev, panel);
419 
420 	return bridge;
421 }
422 EXPORT_SYMBOL(devm_drm_of_get_bridge);
423 #endif
424