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 <linux/debugfs.h>
  8#include <linux/export.h>
  9
 10#include <drm/drm_atomic_helper.h>
 11#include <drm/drm_bridge.h>
 12#include <drm/drm_connector.h>
 13#include <drm/drm_encoder.h>
 14#include <drm/drm_managed.h>
 15#include <drm/drm_modeset_helper_vtables.h>
 16#include <drm/drm_of.h>
 17#include <drm/drm_panel.h>
 18#include <drm/drm_print.h>
 19#include <drm/drm_probe_helper.h>
 20
 21struct panel_bridge {
 22	struct drm_bridge bridge;
 23	struct drm_connector connector;
 24	struct drm_panel *panel;
 25	u32 connector_type;
 26};
 27
 28static inline struct panel_bridge *
 29drm_bridge_to_panel_bridge(struct drm_bridge *bridge)
 30{
 31	return container_of(bridge, struct panel_bridge, bridge);
 32}
 33
 34static inline struct panel_bridge *
 35drm_connector_to_panel_bridge(struct drm_connector *connector)
 36{
 37	return container_of(connector, struct panel_bridge, connector);
 38}
 39
 40static int panel_bridge_connector_get_modes(struct drm_connector *connector)
 41{
 42	struct panel_bridge *panel_bridge =
 43		drm_connector_to_panel_bridge(connector);
 44
 45	return drm_panel_get_modes(panel_bridge->panel, connector);
 46}
 47
 48static const struct drm_connector_helper_funcs
 49panel_bridge_connector_helper_funcs = {
 50	.get_modes = panel_bridge_connector_get_modes,
 51};
 52
 53static const struct drm_connector_funcs panel_bridge_connector_funcs = {
 54	.reset = drm_atomic_helper_connector_reset,
 55	.fill_modes = drm_helper_probe_single_connector_modes,
 56	.destroy = drm_connector_cleanup,
 57	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 58	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 59};
 60
 61static int panel_bridge_attach(struct drm_bridge *bridge,
 62			       struct drm_encoder *encoder,
 63			       enum drm_bridge_attach_flags flags)
 64{
 65	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
 66	struct drm_connector *connector = &panel_bridge->connector;
 67	int ret;
 68
 69	if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
 70		return 0;
 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_panel_bridge_set_orientation(connector, bridge);
 84
 85	drm_connector_attach_encoder(&panel_bridge->connector,
 86					  encoder);
 87
 88	if (bridge->dev->registered) {
 89		if (connector->funcs->reset)
 90			connector->funcs->reset(connector);
 91		drm_connector_register(connector);
 92	}
 93
 94	return 0;
 95}
 96
 97static void panel_bridge_detach(struct drm_bridge *bridge)
 98{
 99	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
100	struct drm_connector *connector = &panel_bridge->connector;
101
102	/*
103	 * Cleanup the connector if we know it was initialized.
104	 *
105	 * FIXME: This wouldn't be needed if the panel_bridge structure was
106	 * allocated with drmm_kzalloc(). This might be tricky since the
107	 * drm_device pointer can only be retrieved when the bridge is attached.
108	 */
109	if (connector->dev)
110		drm_connector_cleanup(connector);
111}
112
113static void panel_bridge_atomic_pre_enable(struct drm_bridge *bridge,
114					   struct drm_atomic_state *atomic_state)
115{
116	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
117	struct drm_encoder *encoder = bridge->encoder;
118	struct drm_crtc *crtc;
119	struct drm_crtc_state *old_crtc_state;
120
121	crtc = drm_atomic_get_new_crtc_for_encoder(atomic_state, encoder);
122	if (!crtc)
123		return;
124
125	old_crtc_state = drm_atomic_get_old_crtc_state(atomic_state, crtc);
126	if (old_crtc_state && old_crtc_state->self_refresh_active)
127		return;
128
129	drm_panel_prepare(panel_bridge->panel);
130}
131
132static void panel_bridge_atomic_enable(struct drm_bridge *bridge,
133				       struct drm_atomic_state *atomic_state)
134{
135	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
136	struct drm_encoder *encoder = bridge->encoder;
137	struct drm_crtc *crtc;
138	struct drm_crtc_state *old_crtc_state;
139
140	crtc = drm_atomic_get_new_crtc_for_encoder(atomic_state, encoder);
141	if (!crtc)
142		return;
143
144	old_crtc_state = drm_atomic_get_old_crtc_state(atomic_state, crtc);
145	if (old_crtc_state && old_crtc_state->self_refresh_active)
146		return;
147
148	drm_panel_enable(panel_bridge->panel);
149}
150
151static void panel_bridge_atomic_disable(struct drm_bridge *bridge,
152					struct drm_atomic_state *atomic_state)
153{
154	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
155	struct drm_encoder *encoder = bridge->encoder;
156	struct drm_crtc *crtc;
157	struct drm_crtc_state *new_crtc_state;
158
159	crtc = drm_atomic_get_old_crtc_for_encoder(atomic_state, encoder);
160	if (!crtc)
161		return;
162
163	new_crtc_state = drm_atomic_get_new_crtc_state(atomic_state, crtc);
164	if (new_crtc_state && new_crtc_state->self_refresh_active)
165		return;
166
167	drm_panel_disable(panel_bridge->panel);
168}
169
170static void panel_bridge_atomic_post_disable(struct drm_bridge *bridge,
171					     struct drm_atomic_state *atomic_state)
172{
173	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
174	struct drm_encoder *encoder = bridge->encoder;
175	struct drm_crtc *crtc;
176	struct drm_crtc_state *new_crtc_state;
177
178	crtc = drm_atomic_get_old_crtc_for_encoder(atomic_state, encoder);
179	if (!crtc)
180		return;
181
182	new_crtc_state = drm_atomic_get_new_crtc_state(atomic_state, crtc);
183	if (new_crtc_state && new_crtc_state->self_refresh_active)
184		return;
185
186	drm_panel_unprepare(panel_bridge->panel);
187}
188
189static int panel_bridge_get_modes(struct drm_bridge *bridge,
190				  struct drm_connector *connector)
191{
192	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
193
194	return drm_panel_get_modes(panel_bridge->panel, connector);
195}
196
197static void panel_bridge_debugfs_init(struct drm_bridge *bridge,
198				      struct dentry *root)
199{
200	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
201	struct drm_panel *panel = panel_bridge->panel;
202
203	root = debugfs_create_dir("panel", root);
204	if (panel->funcs->debugfs_init)
205		panel->funcs->debugfs_init(panel, root);
206}
207
208static const struct drm_bridge_funcs panel_bridge_bridge_funcs = {
209	.attach = panel_bridge_attach,
210	.detach = panel_bridge_detach,
211	.atomic_pre_enable = panel_bridge_atomic_pre_enable,
212	.atomic_enable = panel_bridge_atomic_enable,
213	.atomic_disable = panel_bridge_atomic_disable,
214	.atomic_post_disable = panel_bridge_atomic_post_disable,
215	.get_modes = panel_bridge_get_modes,
216	.atomic_reset = drm_atomic_helper_bridge_reset,
217	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
218	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
219	.atomic_get_input_bus_fmts = drm_atomic_helper_bridge_propagate_bus_fmt,
220	.debugfs_init = panel_bridge_debugfs_init,
221};
222
223/**
224 * drm_bridge_is_panel - Checks if a drm_bridge is a panel_bridge.
225 *
226 * @bridge: The drm_bridge to be checked.
227 *
228 * Returns true if the bridge is a panel bridge, or false otherwise.
229 */
230bool drm_bridge_is_panel(const struct drm_bridge *bridge)
231{
232	return bridge->funcs == &panel_bridge_bridge_funcs;
233}
234EXPORT_SYMBOL(drm_bridge_is_panel);
235
236/**
237 * drm_panel_bridge_add - Creates a &drm_bridge and &drm_connector that
238 * just calls the appropriate functions from &drm_panel.
239 *
240 * @panel: The drm_panel being wrapped.  Must be non-NULL.
241 *
242 * For drivers converting from directly using drm_panel: The expected
243 * usage pattern is that during either encoder module probe or DSI
244 * host attach, a drm_panel will be looked up through
245 * drm_of_find_panel_or_bridge().  drm_panel_bridge_add() is used to
246 * wrap that panel in the new bridge, and the result can then be
247 * passed to drm_bridge_attach().  The drm_panel_prepare() and related
248 * functions can be dropped from the encoder driver (they're now
249 * called by the KMS helpers before calling into the encoder), along
250 * with connector creation.  When done with the bridge (after
251 * drm_mode_config_cleanup() if the bridge has already been attached), then
252 * drm_panel_bridge_remove() to free it.
253 *
254 * The connector type is set to @panel->connector_type, which must be set to a
255 * known type. Calling this function with a panel whose connector type is
256 * DRM_MODE_CONNECTOR_Unknown will return ERR_PTR(-EINVAL).
257 *
258 * See devm_drm_panel_bridge_add() for an automatically managed version of this
259 * function.
260 */
261struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel)
262{
263	if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
264		return ERR_PTR(-EINVAL);
265
266	return drm_panel_bridge_add_typed(panel, panel->connector_type);
267}
268EXPORT_SYMBOL(drm_panel_bridge_add);
269
270/**
271 * drm_panel_bridge_add_typed - Creates a &drm_bridge and &drm_connector with
272 * an explicit connector type.
273 * @panel: The drm_panel being wrapped.  Must be non-NULL.
274 * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
275 *
276 * This is just like drm_panel_bridge_add(), but forces the connector type to
277 * @connector_type instead of infering it from the panel.
278 *
279 * This function is deprecated and should not be used in new drivers. Use
280 * drm_panel_bridge_add() instead, and fix panel drivers as necessary if they
281 * don't report a connector type.
282 */
283struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
284					      u32 connector_type)
285{
286	struct panel_bridge *panel_bridge;
287
288	if (!panel)
289		return ERR_PTR(-EINVAL);
290
291	panel_bridge = devm_drm_bridge_alloc(panel->dev, struct panel_bridge, bridge,
292					     &panel_bridge_bridge_funcs);
293	if (IS_ERR(panel_bridge))
294		return (void *)panel_bridge;
295
296	panel_bridge->connector_type = connector_type;
297	panel_bridge->panel = panel;
298
299	panel_bridge->bridge.of_node = panel->dev->of_node;
300	panel_bridge->bridge.ops = DRM_BRIDGE_OP_MODES;
301	panel_bridge->bridge.type = connector_type;
302	panel_bridge->bridge.pre_enable_prev_first = panel->prepare_prev_first;
303
304	drm_bridge_add(&panel_bridge->bridge);
305
306	return &panel_bridge->bridge;
307}
308EXPORT_SYMBOL(drm_panel_bridge_add_typed);
309
310/**
311 * drm_panel_bridge_remove - Unregisters and frees a drm_bridge
312 * created by drm_panel_bridge_add().
313 *
314 * @bridge: The drm_bridge being freed.
315 */
316void drm_panel_bridge_remove(struct drm_bridge *bridge)
317{
318	struct panel_bridge *panel_bridge;
319
320	if (!bridge)
321		return;
322
323	if (!drm_bridge_is_panel(bridge)) {
324		drm_warn(bridge->dev, "%s: called on non-panel bridge!\n", __func__);
325		return;
326	}
327
328	panel_bridge = drm_bridge_to_panel_bridge(bridge);
329
330	drm_bridge_remove(bridge);
331	/* TODO remove this after reworking panel_bridge lifetime */
332	devm_drm_put_bridge(panel_bridge->panel->dev, bridge);
333}
334EXPORT_SYMBOL(drm_panel_bridge_remove);
335
336/**
337 * drm_panel_bridge_set_orientation - Set the connector's panel orientation
338 * from the bridge that can be transformed to panel bridge.
339 *
340 * @connector: The connector to be set panel orientation.
341 * @bridge: The drm_bridge to be transformed to panel bridge.
342 *
343 * Returns 0 on success, negative errno on failure.
344 */
345int drm_panel_bridge_set_orientation(struct drm_connector *connector,
346				     struct drm_bridge *bridge)
347{
348	struct panel_bridge *panel_bridge;
349
350	panel_bridge = drm_bridge_to_panel_bridge(bridge);
351
352	return drm_connector_set_orientation_from_panel(connector,
353							panel_bridge->panel);
354}
355EXPORT_SYMBOL(drm_panel_bridge_set_orientation);
356
357static void devm_drm_panel_bridge_release(struct device *dev, void *res)
358{
359	struct drm_bridge *bridge = *(struct drm_bridge **)res;
360
361	if (!bridge)
362		return;
363
364	drm_bridge_remove(bridge);
365}
366
367/**
368 * devm_drm_panel_bridge_add - Creates a managed &drm_bridge and &drm_connector
369 * that just calls the appropriate functions from &drm_panel.
370 * @dev: device to tie the bridge lifetime to
371 * @panel: The drm_panel being wrapped.  Must be non-NULL.
372 *
373 * This is the managed version of drm_panel_bridge_add() which automatically
374 * calls drm_panel_bridge_remove() when @dev is unbound.
375 */
376struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
377					     struct drm_panel *panel)
378{
379	if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
380		return ERR_PTR(-EINVAL);
381
382	return devm_drm_panel_bridge_add_typed(dev, panel,
383					       panel->connector_type);
384}
385EXPORT_SYMBOL(devm_drm_panel_bridge_add);
386
387/**
388 * devm_drm_panel_bridge_add_typed - Creates a managed &drm_bridge and
389 * &drm_connector with an explicit connector type.
390 * @dev: device to tie the bridge lifetime to
391 * @panel: The drm_panel being wrapped.  Must be non-NULL.
392 * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
393 *
394 * This is just like devm_drm_panel_bridge_add(), but forces the connector type
395 * to @connector_type instead of infering it from the panel.
396 *
397 * This function is deprecated and should not be used in new drivers. Use
398 * devm_drm_panel_bridge_add() instead, and fix panel drivers as necessary if
399 * they don't report a connector type.
400 */
401struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev,
402						   struct drm_panel *panel,
403						   u32 connector_type)
404{
405	struct drm_bridge **ptr, *bridge;
406
407	ptr = devres_alloc(devm_drm_panel_bridge_release, sizeof(*ptr),
408			   GFP_KERNEL);
409	if (!ptr)
410		return ERR_PTR(-ENOMEM);
411
412	bridge = drm_panel_bridge_add_typed(panel, connector_type);
413	if (IS_ERR(bridge)) {
414		devres_free(ptr);
415		return bridge;
416	}
417
418	*ptr = bridge;
419	devres_add(dev, ptr);
420
421	return bridge;
422}
423EXPORT_SYMBOL(devm_drm_panel_bridge_add_typed);
424
425static void drmm_drm_panel_bridge_release(struct drm_device *drm, void *ptr)
426{
427	struct drm_bridge *bridge = ptr;
428
429	drm_panel_bridge_remove(bridge);
430}
431
432/**
433 * drmm_panel_bridge_add - Creates a DRM-managed &drm_bridge and
434 *                         &drm_connector that just calls the
435 *                         appropriate functions from &drm_panel.
436 *
437 * @drm: DRM device to tie the bridge lifetime to
438 * @panel: The drm_panel being wrapped.  Must be non-NULL.
439 *
440 * This is the DRM-managed version of drm_panel_bridge_add() which
441 * automatically calls drm_panel_bridge_remove() when @dev is cleaned
442 * up.
443 */
444struct drm_bridge *drmm_panel_bridge_add(struct drm_device *drm,
445					 struct drm_panel *panel)
446{
447	struct drm_bridge *bridge;
448	int ret;
449
450	bridge = drm_panel_bridge_add_typed(panel, panel->connector_type);
451	if (IS_ERR(bridge))
452		return bridge;
453
454	ret = drmm_add_action_or_reset(drm, drmm_drm_panel_bridge_release,
455				       bridge);
456	if (ret)
457		return ERR_PTR(ret);
458
459	return bridge;
460}
461EXPORT_SYMBOL(drmm_panel_bridge_add);
462
463/**
464 * drm_panel_bridge_connector - return the connector for the panel bridge
465 * @bridge: The drm_bridge.
466 *
467 * drm_panel_bridge creates the connector.
468 * This function gives external access to the connector.
469 *
470 * Returns: Pointer to drm_connector
471 */
472struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge)
473{
474	struct panel_bridge *panel_bridge;
475
476	panel_bridge = drm_bridge_to_panel_bridge(bridge);
477
478	return &panel_bridge->connector;
479}
480EXPORT_SYMBOL(drm_panel_bridge_connector);
481
482#ifdef CONFIG_OF
483/**
484 * devm_drm_of_get_bridge - Return next bridge in the chain
485 * @dev: device to tie the bridge lifetime to
486 * @np: device tree node containing encoder output ports
487 * @port: port in the device tree node
488 * @endpoint: endpoint in the device tree node
489 *
490 * Given a DT node's port and endpoint number, finds the connected node
491 * and returns the associated bridge if any, or creates and returns a
492 * drm panel bridge instance if a panel is connected.
493 *
494 * Returns a pointer to the bridge if successful, or an error pointer
495 * otherwise.
496 */
497struct drm_bridge *devm_drm_of_get_bridge(struct device *dev,
498					  struct device_node *np,
499					  u32 port, u32 endpoint)
500{
501	struct drm_bridge *bridge;
502	struct drm_panel *panel;
503	int ret;
504
505	ret = drm_of_find_panel_or_bridge(np, port, endpoint,
506					  &panel, &bridge);
507	if (ret)
508		return ERR_PTR(ret);
509
510	if (panel)
511		bridge = devm_drm_panel_bridge_add(dev, panel);
512
513	return bridge;
514}
515EXPORT_SYMBOL(devm_drm_of_get_bridge);
516
517/**
518 * drmm_of_get_bridge - Return next bridge in the chain
519 * @drm: device to tie the bridge lifetime to
520 * @np: device tree node containing encoder output ports
521 * @port: port in the device tree node
522 * @endpoint: endpoint in the device tree node
523 *
524 * Given a DT node's port and endpoint number, finds the connected node
525 * and returns the associated bridge if any, or creates and returns a
526 * drm panel bridge instance if a panel is connected.
527 *
528 * Returns a drmm managed pointer to the bridge if successful, or an error
529 * pointer otherwise.
530 */
531struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm,
532				      struct device_node *np,
533				      u32 port, u32 endpoint)
534{
535	struct drm_bridge *bridge;
536	struct drm_panel *panel;
537	int ret;
538
539	ret = drm_of_find_panel_or_bridge(np, port, endpoint,
540					  &panel, &bridge);
541	if (ret)
542		return ERR_PTR(ret);
543
544	if (panel)
545		bridge = drmm_panel_bridge_add(drm, panel);
546
547	return bridge;
548}
549EXPORT_SYMBOL(drmm_of_get_bridge);
550
551#endif