xref: /linux/drivers/gpu/drm/bridge/panel.c (revision f82fe0d44913248877450584c27992c5b0f96ce7)
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 <linux/debugfs.h>
8 
9 #include <drm/drm_atomic_helper.h>
10 #include <drm/drm_bridge.h>
11 #include <drm/drm_connector.h>
12 #include <drm/drm_encoder.h>
13 #include <drm/drm_managed.h>
14 #include <drm/drm_modeset_helper_vtables.h>
15 #include <drm/drm_of.h>
16 #include <drm/drm_panel.h>
17 #include <drm/drm_print.h>
18 #include <drm/drm_probe_helper.h>
19 
20 struct panel_bridge {
21 	struct drm_bridge bridge;
22 	struct drm_connector connector;
23 	struct drm_panel *panel;
24 	u32 connector_type;
25 };
26 
27 static inline struct panel_bridge *
28 drm_bridge_to_panel_bridge(struct drm_bridge *bridge)
29 {
30 	return container_of(bridge, struct panel_bridge, bridge);
31 }
32 
33 static inline struct panel_bridge *
34 drm_connector_to_panel_bridge(struct drm_connector *connector)
35 {
36 	return container_of(connector, struct panel_bridge, connector);
37 }
38 
39 static int panel_bridge_connector_get_modes(struct drm_connector *connector)
40 {
41 	struct panel_bridge *panel_bridge =
42 		drm_connector_to_panel_bridge(connector);
43 
44 	return drm_panel_get_modes(panel_bridge->panel, connector);
45 }
46 
47 static const struct drm_connector_helper_funcs
48 panel_bridge_connector_helper_funcs = {
49 	.get_modes = panel_bridge_connector_get_modes,
50 };
51 
52 static const struct drm_connector_funcs panel_bridge_connector_funcs = {
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 panel_bridge_attach(struct drm_bridge *bridge,
61 			       enum drm_bridge_attach_flags flags)
62 {
63 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
64 	struct drm_connector *connector = &panel_bridge->connector;
65 	int ret;
66 
67 	if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
68 		return 0;
69 
70 	drm_connector_helper_add(connector,
71 				 &panel_bridge_connector_helper_funcs);
72 
73 	ret = drm_connector_init(bridge->dev, connector,
74 				 &panel_bridge_connector_funcs,
75 				 panel_bridge->connector_type);
76 	if (ret) {
77 		DRM_ERROR("Failed to initialize connector\n");
78 		return ret;
79 	}
80 
81 	drm_panel_bridge_set_orientation(connector, bridge);
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_atomic_pre_enable(struct drm_bridge *bridge,
112 					   struct drm_atomic_state *atomic_state)
113 {
114 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
115 	struct drm_encoder *encoder = bridge->encoder;
116 	struct drm_crtc *crtc;
117 	struct drm_crtc_state *old_crtc_state;
118 
119 	crtc = drm_atomic_get_new_crtc_for_encoder(atomic_state, encoder);
120 	if (!crtc)
121 		return;
122 
123 	old_crtc_state = drm_atomic_get_old_crtc_state(atomic_state, crtc);
124 	if (old_crtc_state && old_crtc_state->self_refresh_active)
125 		return;
126 
127 	drm_panel_prepare(panel_bridge->panel);
128 }
129 
130 static void panel_bridge_atomic_enable(struct drm_bridge *bridge,
131 				       struct drm_atomic_state *atomic_state)
132 {
133 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
134 	struct drm_encoder *encoder = bridge->encoder;
135 	struct drm_crtc *crtc;
136 	struct drm_crtc_state *old_crtc_state;
137 
138 	crtc = drm_atomic_get_new_crtc_for_encoder(atomic_state, encoder);
139 	if (!crtc)
140 		return;
141 
142 	old_crtc_state = drm_atomic_get_old_crtc_state(atomic_state, crtc);
143 	if (old_crtc_state && old_crtc_state->self_refresh_active)
144 		return;
145 
146 	drm_panel_enable(panel_bridge->panel);
147 }
148 
149 static void panel_bridge_atomic_disable(struct drm_bridge *bridge,
150 					struct drm_atomic_state *atomic_state)
151 {
152 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
153 	struct drm_encoder *encoder = bridge->encoder;
154 	struct drm_crtc *crtc;
155 	struct drm_crtc_state *new_crtc_state;
156 
157 	crtc = drm_atomic_get_old_crtc_for_encoder(atomic_state, encoder);
158 	if (!crtc)
159 		return;
160 
161 	new_crtc_state = drm_atomic_get_new_crtc_state(atomic_state, crtc);
162 	if (new_crtc_state && new_crtc_state->self_refresh_active)
163 		return;
164 
165 	drm_panel_disable(panel_bridge->panel);
166 }
167 
168 static void panel_bridge_atomic_post_disable(struct drm_bridge *bridge,
169 					     struct drm_atomic_state *atomic_state)
170 {
171 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
172 	struct drm_encoder *encoder = bridge->encoder;
173 	struct drm_crtc *crtc;
174 	struct drm_crtc_state *new_crtc_state;
175 
176 	crtc = drm_atomic_get_old_crtc_for_encoder(atomic_state, encoder);
177 	if (!crtc)
178 		return;
179 
180 	new_crtc_state = drm_atomic_get_new_crtc_state(atomic_state, crtc);
181 	if (new_crtc_state && new_crtc_state->self_refresh_active)
182 		return;
183 
184 	drm_panel_unprepare(panel_bridge->panel);
185 }
186 
187 static int panel_bridge_get_modes(struct drm_bridge *bridge,
188 				  struct drm_connector *connector)
189 {
190 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
191 
192 	return drm_panel_get_modes(panel_bridge->panel, connector);
193 }
194 
195 static void panel_bridge_debugfs_init(struct drm_bridge *bridge,
196 				      struct dentry *root)
197 {
198 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
199 	struct drm_panel *panel = panel_bridge->panel;
200 
201 	root = debugfs_create_dir("panel", root);
202 	if (panel->funcs->debugfs_init)
203 		panel->funcs->debugfs_init(panel, root);
204 }
205 
206 static const struct drm_bridge_funcs panel_bridge_bridge_funcs = {
207 	.attach = panel_bridge_attach,
208 	.detach = panel_bridge_detach,
209 	.atomic_pre_enable = panel_bridge_atomic_pre_enable,
210 	.atomic_enable = panel_bridge_atomic_enable,
211 	.atomic_disable = panel_bridge_atomic_disable,
212 	.atomic_post_disable = panel_bridge_atomic_post_disable,
213 	.get_modes = panel_bridge_get_modes,
214 	.atomic_reset = drm_atomic_helper_bridge_reset,
215 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
216 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
217 	.atomic_get_input_bus_fmts = drm_atomic_helper_bridge_propagate_bus_fmt,
218 	.debugfs_init = panel_bridge_debugfs_init,
219 };
220 
221 /**
222  * drm_bridge_is_panel - Checks if a drm_bridge is a panel_bridge.
223  *
224  * @bridge: The drm_bridge to be checked.
225  *
226  * Returns true if the bridge is a panel bridge, or false otherwise.
227  */
228 bool drm_bridge_is_panel(const struct drm_bridge *bridge)
229 {
230 	return bridge->funcs == &panel_bridge_bridge_funcs;
231 }
232 EXPORT_SYMBOL(drm_bridge_is_panel);
233 
234 /**
235  * drm_panel_bridge_add - Creates a &drm_bridge and &drm_connector that
236  * just calls the appropriate functions from &drm_panel.
237  *
238  * @panel: The drm_panel being wrapped.  Must be non-NULL.
239  *
240  * For drivers converting from directly using drm_panel: The expected
241  * usage pattern is that during either encoder module probe or DSI
242  * host attach, a drm_panel will be looked up through
243  * drm_of_find_panel_or_bridge().  drm_panel_bridge_add() is used to
244  * wrap that panel in the new bridge, and the result can then be
245  * passed to drm_bridge_attach().  The drm_panel_prepare() and related
246  * functions can be dropped from the encoder driver (they're now
247  * called by the KMS helpers before calling into the encoder), along
248  * with connector creation.  When done with the bridge (after
249  * drm_mode_config_cleanup() if the bridge has already been attached), then
250  * drm_panel_bridge_remove() to free it.
251  *
252  * The connector type is set to @panel->connector_type, which must be set to a
253  * known type. Calling this function with a panel whose connector type is
254  * DRM_MODE_CONNECTOR_Unknown will return ERR_PTR(-EINVAL).
255  *
256  * See devm_drm_panel_bridge_add() for an automatically managed version of this
257  * function.
258  */
259 struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel)
260 {
261 	if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
262 		return ERR_PTR(-EINVAL);
263 
264 	return drm_panel_bridge_add_typed(panel, panel->connector_type);
265 }
266 EXPORT_SYMBOL(drm_panel_bridge_add);
267 
268 /**
269  * drm_panel_bridge_add_typed - Creates a &drm_bridge and &drm_connector with
270  * an explicit connector type.
271  * @panel: The drm_panel being wrapped.  Must be non-NULL.
272  * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
273  *
274  * This is just like drm_panel_bridge_add(), but forces the connector type to
275  * @connector_type instead of infering it from the panel.
276  *
277  * This function is deprecated and should not be used in new drivers. Use
278  * drm_panel_bridge_add() instead, and fix panel drivers as necessary if they
279  * don't report a connector type.
280  */
281 struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
282 					      u32 connector_type)
283 {
284 	struct panel_bridge *panel_bridge;
285 
286 	if (!panel)
287 		return ERR_PTR(-EINVAL);
288 
289 	panel_bridge = devm_kzalloc(panel->dev, sizeof(*panel_bridge),
290 				    GFP_KERNEL);
291 	if (!panel_bridge)
292 		return ERR_PTR(-ENOMEM);
293 
294 	panel_bridge->connector_type = connector_type;
295 	panel_bridge->panel = panel;
296 
297 	panel_bridge->bridge.funcs = &panel_bridge_bridge_funcs;
298 	panel_bridge->bridge.of_node = panel->dev->of_node;
299 	panel_bridge->bridge.ops = DRM_BRIDGE_OP_MODES;
300 	panel_bridge->bridge.type = connector_type;
301 
302 	drm_bridge_add(&panel_bridge->bridge);
303 
304 	return &panel_bridge->bridge;
305 }
306 EXPORT_SYMBOL(drm_panel_bridge_add_typed);
307 
308 /**
309  * drm_panel_bridge_remove - Unregisters and frees a drm_bridge
310  * created by drm_panel_bridge_add().
311  *
312  * @bridge: The drm_bridge being freed.
313  */
314 void drm_panel_bridge_remove(struct drm_bridge *bridge)
315 {
316 	struct panel_bridge *panel_bridge;
317 
318 	if (!bridge)
319 		return;
320 
321 	if (!drm_bridge_is_panel(bridge)) {
322 		drm_warn(bridge->dev, "%s: called on non-panel bridge!\n", __func__);
323 		return;
324 	}
325 
326 	panel_bridge = drm_bridge_to_panel_bridge(bridge);
327 
328 	drm_bridge_remove(bridge);
329 	devm_kfree(panel_bridge->panel->dev, bridge);
330 }
331 EXPORT_SYMBOL(drm_panel_bridge_remove);
332 
333 /**
334  * drm_panel_bridge_set_orientation - Set the connector's panel orientation
335  * from the bridge that can be transformed to panel bridge.
336  *
337  * @connector: The connector to be set panel orientation.
338  * @bridge: The drm_bridge to be transformed to panel bridge.
339  *
340  * Returns 0 on success, negative errno on failure.
341  */
342 int drm_panel_bridge_set_orientation(struct drm_connector *connector,
343 				     struct drm_bridge *bridge)
344 {
345 	struct panel_bridge *panel_bridge;
346 
347 	panel_bridge = drm_bridge_to_panel_bridge(bridge);
348 
349 	return drm_connector_set_orientation_from_panel(connector,
350 							panel_bridge->panel);
351 }
352 EXPORT_SYMBOL(drm_panel_bridge_set_orientation);
353 
354 static void devm_drm_panel_bridge_release(struct device *dev, void *res)
355 {
356 	struct drm_bridge *bridge = *(struct drm_bridge **)res;
357 
358 	if (!bridge)
359 		return;
360 
361 	drm_bridge_remove(bridge);
362 }
363 
364 /**
365  * devm_drm_panel_bridge_add - Creates a managed &drm_bridge and &drm_connector
366  * that just calls the appropriate functions from &drm_panel.
367  * @dev: device to tie the bridge lifetime to
368  * @panel: The drm_panel being wrapped.  Must be non-NULL.
369  *
370  * This is the managed version of drm_panel_bridge_add() which automatically
371  * calls drm_panel_bridge_remove() when @dev is unbound.
372  */
373 struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
374 					     struct drm_panel *panel)
375 {
376 	if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
377 		return ERR_PTR(-EINVAL);
378 
379 	return devm_drm_panel_bridge_add_typed(dev, panel,
380 					       panel->connector_type);
381 }
382 EXPORT_SYMBOL(devm_drm_panel_bridge_add);
383 
384 /**
385  * devm_drm_panel_bridge_add_typed - Creates a managed &drm_bridge and
386  * &drm_connector with an explicit connector type.
387  * @dev: device to tie the bridge lifetime to
388  * @panel: The drm_panel being wrapped.  Must be non-NULL.
389  * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
390  *
391  * This is just like devm_drm_panel_bridge_add(), but forces the connector type
392  * to @connector_type instead of infering it from the panel.
393  *
394  * This function is deprecated and should not be used in new drivers. Use
395  * devm_drm_panel_bridge_add() instead, and fix panel drivers as necessary if
396  * they don't report a connector type.
397  */
398 struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev,
399 						   struct drm_panel *panel,
400 						   u32 connector_type)
401 {
402 	struct drm_bridge **ptr, *bridge;
403 
404 	ptr = devres_alloc(devm_drm_panel_bridge_release, sizeof(*ptr),
405 			   GFP_KERNEL);
406 	if (!ptr)
407 		return ERR_PTR(-ENOMEM);
408 
409 	bridge = drm_panel_bridge_add_typed(panel, connector_type);
410 	if (IS_ERR(bridge)) {
411 		devres_free(ptr);
412 		return bridge;
413 	}
414 
415 	bridge->pre_enable_prev_first = panel->prepare_prev_first;
416 
417 	*ptr = bridge;
418 	devres_add(dev, ptr);
419 
420 	return bridge;
421 }
422 EXPORT_SYMBOL(devm_drm_panel_bridge_add_typed);
423 
424 static void drmm_drm_panel_bridge_release(struct drm_device *drm, void *ptr)
425 {
426 	struct drm_bridge *bridge = ptr;
427 
428 	drm_panel_bridge_remove(bridge);
429 }
430 
431 /**
432  * drmm_panel_bridge_add - Creates a DRM-managed &drm_bridge and
433  *                         &drm_connector that just calls the
434  *                         appropriate functions from &drm_panel.
435  *
436  * @drm: DRM device to tie the bridge lifetime to
437  * @panel: The drm_panel being wrapped.  Must be non-NULL.
438  *
439  * This is the DRM-managed version of drm_panel_bridge_add() which
440  * automatically calls drm_panel_bridge_remove() when @dev is cleaned
441  * up.
442  */
443 struct drm_bridge *drmm_panel_bridge_add(struct drm_device *drm,
444 					 struct drm_panel *panel)
445 {
446 	struct drm_bridge *bridge;
447 	int ret;
448 
449 	bridge = drm_panel_bridge_add_typed(panel, panel->connector_type);
450 	if (IS_ERR(bridge))
451 		return bridge;
452 
453 	ret = drmm_add_action_or_reset(drm, drmm_drm_panel_bridge_release,
454 				       bridge);
455 	if (ret)
456 		return ERR_PTR(ret);
457 
458 	bridge->pre_enable_prev_first = panel->prepare_prev_first;
459 
460 	return bridge;
461 }
462 EXPORT_SYMBOL(drmm_panel_bridge_add);
463 
464 /**
465  * drm_panel_bridge_connector - return the connector for the panel bridge
466  * @bridge: The drm_bridge.
467  *
468  * drm_panel_bridge creates the connector.
469  * This function gives external access to the connector.
470  *
471  * Returns: Pointer to drm_connector
472  */
473 struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge)
474 {
475 	struct panel_bridge *panel_bridge;
476 
477 	panel_bridge = drm_bridge_to_panel_bridge(bridge);
478 
479 	return &panel_bridge->connector;
480 }
481 EXPORT_SYMBOL(drm_panel_bridge_connector);
482 
483 #ifdef CONFIG_OF
484 /**
485  * devm_drm_of_get_bridge - Return next bridge in the chain
486  * @dev: device to tie the bridge lifetime to
487  * @np: device tree node containing encoder output ports
488  * @port: port in the device tree node
489  * @endpoint: endpoint in the device tree node
490  *
491  * Given a DT node's port and endpoint number, finds the connected node
492  * and returns the associated bridge if any, or creates and returns a
493  * drm panel bridge instance if a panel is connected.
494  *
495  * Returns a pointer to the bridge if successful, or an error pointer
496  * otherwise.
497  */
498 struct drm_bridge *devm_drm_of_get_bridge(struct device *dev,
499 					  struct device_node *np,
500 					  u32 port, u32 endpoint)
501 {
502 	struct drm_bridge *bridge;
503 	struct drm_panel *panel;
504 	int ret;
505 
506 	ret = drm_of_find_panel_or_bridge(np, port, endpoint,
507 					  &panel, &bridge);
508 	if (ret)
509 		return ERR_PTR(ret);
510 
511 	if (panel)
512 		bridge = devm_drm_panel_bridge_add(dev, panel);
513 
514 	return bridge;
515 }
516 EXPORT_SYMBOL(devm_drm_of_get_bridge);
517 
518 /**
519  * drmm_of_get_bridge - Return next bridge in the chain
520  * @drm: device to tie the bridge lifetime to
521  * @np: device tree node containing encoder output ports
522  * @port: port in the device tree node
523  * @endpoint: endpoint in the device tree node
524  *
525  * Given a DT node's port and endpoint number, finds the connected node
526  * and returns the associated bridge if any, or creates and returns a
527  * drm panel bridge instance if a panel is connected.
528  *
529  * Returns a drmm managed pointer to the bridge if successful, or an error
530  * pointer otherwise.
531  */
532 struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm,
533 				      struct device_node *np,
534 				      u32 port, u32 endpoint)
535 {
536 	struct drm_bridge *bridge;
537 	struct drm_panel *panel;
538 	int ret;
539 
540 	ret = drm_of_find_panel_or_bridge(np, port, endpoint,
541 					  &panel, &bridge);
542 	if (ret)
543 		return ERR_PTR(ret);
544 
545 	if (panel)
546 		bridge = drmm_panel_bridge_add(drm, panel);
547 
548 	return bridge;
549 }
550 EXPORT_SYMBOL(drmm_of_get_bridge);
551 
552 #endif
553