xref: /linux/drivers/gpu/drm/display/drm_bridge_connector.c (revision 815e260a18a3af4dab59025ee99a7156c0e8b5e0)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2019 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
4  */
5 
6 #include <linux/export.h>
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/of.h>
10 #include <linux/property.h>
11 #include <linux/slab.h>
12 
13 #include <drm/drm_atomic_state_helper.h>
14 #include <drm/drm_bridge.h>
15 #include <drm/drm_bridge_connector.h>
16 #include <drm/drm_connector.h>
17 #include <drm/drm_device.h>
18 #include <drm/drm_edid.h>
19 #include <drm/drm_managed.h>
20 #include <drm/drm_modeset_helper_vtables.h>
21 #include <drm/drm_print.h>
22 #include <drm/drm_probe_helper.h>
23 #include <drm/display/drm_hdcp_helper.h>
24 #include <drm/display/drm_hdmi_audio_helper.h>
25 #include <drm/display/drm_hdmi_cec_helper.h>
26 #include <drm/display/drm_hdmi_helper.h>
27 #include <drm/display/drm_hdmi_state_helper.h>
28 
29 /**
30  * DOC: overview
31  *
32  * The DRM bridge connector helper object provides a DRM connector
33  * implementation that wraps a chain of &struct drm_bridge. The connector
34  * operations are fully implemented based on the operations of the bridges in
35  * the chain, and don't require any intervention from the display controller
36  * driver at runtime.
37  *
38  * To use the helper, display controller drivers create a bridge connector with
39  * a call to drm_bridge_connector_init(). This associates the newly created
40  * connector with the chain of bridges passed to the function and registers it
41  * with the DRM device. At that point the connector becomes fully usable, no
42  * further operation is needed.
43  *
44  * The DRM bridge connector operations are implemented based on the operations
45  * provided by the bridges in the chain. Each connector operation is delegated
46  * to the bridge closest to the connector (at the end of the chain) that
47  * provides the relevant functionality.
48  *
49  * To make use of this helper, all bridges in the chain shall report bridge
50  * operation flags (&drm_bridge->ops) and bridge output type
51  * (&drm_bridge->type), as well as the DRM_BRIDGE_ATTACH_NO_CONNECTOR attach
52  * flag (none of the bridges shall create a DRM connector directly).
53  */
54 
55 /**
56  * struct drm_bridge_connector - A connector backed by a chain of bridges
57  */
58 struct drm_bridge_connector {
59 	/**
60 	 * @base: The base DRM connector
61 	 */
62 	struct drm_connector base;
63 	/**
64 	 * @encoder:
65 	 *
66 	 * The encoder at the start of the bridges chain.
67 	 */
68 	struct drm_encoder *encoder;
69 	/**
70 	 * @bridge_edid:
71 	 *
72 	 * The last bridge in the chain (closest to the connector) that provides
73 	 * EDID read support, if any (see &DRM_BRIDGE_OP_EDID).
74 	 */
75 	struct drm_bridge *bridge_edid;
76 	/**
77 	 * @bridge_hpd:
78 	 *
79 	 * The last bridge in the chain (closest to the connector) that provides
80 	 * hot-plug detection notification, if any (see &DRM_BRIDGE_OP_HPD).
81 	 */
82 	struct drm_bridge *bridge_hpd;
83 	/**
84 	 * @bridge_detect:
85 	 *
86 	 * The last bridge in the chain (closest to the connector) that provides
87 	 * connector detection, if any (see &DRM_BRIDGE_OP_DETECT).
88 	 */
89 	struct drm_bridge *bridge_detect;
90 	/**
91 	 * @bridge_modes:
92 	 *
93 	 * The last bridge in the chain (closest to the connector) that provides
94 	 * connector modes detection, if any (see &DRM_BRIDGE_OP_MODES).
95 	 */
96 	struct drm_bridge *bridge_modes;
97 	/**
98 	 * @bridge_hdmi:
99 	 *
100 	 * The bridge in the chain that implements necessary support for the
101 	 * HDMI connector infrastructure, if any (see &DRM_BRIDGE_OP_HDMI).
102 	 */
103 	struct drm_bridge *bridge_hdmi;
104 	/**
105 	 * @bridge_hdmi_audio:
106 	 *
107 	 * The bridge in the chain that implements necessary support for the
108 	 * HDMI Audio infrastructure, if any (see &DRM_BRIDGE_OP_HDMI_AUDIO).
109 	 */
110 	struct drm_bridge *bridge_hdmi_audio;
111 	/**
112 	 * @bridge_dp_audio:
113 	 *
114 	 * The bridge in the chain that implements necessary support for the
115 	 * DisplayPort Audio infrastructure, if any (see
116 	 * &DRM_BRIDGE_OP_DP_AUDIO).
117 	 */
118 	struct drm_bridge *bridge_dp_audio;
119 	/**
120 	 * @bridge_hdmi_cec:
121 	 *
122 	 * The bridge in the chain that implements CEC support, if any (see
123 	 * DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER).
124 	 */
125 	struct drm_bridge *bridge_hdmi_cec;
126 };
127 
128 #define to_drm_bridge_connector(x) \
129 	container_of(x, struct drm_bridge_connector, base)
130 
131 /* -----------------------------------------------------------------------------
132  * Bridge Connector Hot-Plug Handling
133  */
134 
135 static void drm_bridge_connector_hpd_notify(struct drm_connector *connector,
136 					    enum drm_connector_status status)
137 {
138 	struct drm_bridge_connector *bridge_connector =
139 		to_drm_bridge_connector(connector);
140 
141 	/* Notify all bridges in the pipeline of hotplug events. */
142 	drm_for_each_bridge_in_chain_scoped(bridge_connector->encoder, bridge) {
143 		if (bridge->funcs->hpd_notify)
144 			bridge->funcs->hpd_notify(bridge, status);
145 	}
146 }
147 
148 static void drm_bridge_connector_handle_hpd(struct drm_bridge_connector *drm_bridge_connector,
149 					    enum drm_connector_status status)
150 {
151 	struct drm_connector *connector = &drm_bridge_connector->base;
152 	struct drm_device *dev = connector->dev;
153 
154 	mutex_lock(&dev->mode_config.mutex);
155 	connector->status = status;
156 	mutex_unlock(&dev->mode_config.mutex);
157 
158 	drm_bridge_connector_hpd_notify(connector, status);
159 
160 	drm_kms_helper_connector_hotplug_event(connector);
161 }
162 
163 static void drm_bridge_connector_hpd_cb(void *cb_data,
164 					enum drm_connector_status status)
165 {
166 	drm_bridge_connector_handle_hpd(cb_data, status);
167 }
168 
169 static void drm_bridge_connector_oob_hotplug_event(struct drm_connector *connector,
170 						   enum drm_connector_status status)
171 {
172 	struct drm_bridge_connector *bridge_connector =
173 		to_drm_bridge_connector(connector);
174 
175 	drm_bridge_connector_handle_hpd(bridge_connector, status);
176 }
177 
178 static void drm_bridge_connector_enable_hpd(struct drm_connector *connector)
179 {
180 	struct drm_bridge_connector *bridge_connector =
181 		to_drm_bridge_connector(connector);
182 	struct drm_bridge *hpd = bridge_connector->bridge_hpd;
183 
184 	if (hpd)
185 		drm_bridge_hpd_enable(hpd, drm_bridge_connector_hpd_cb,
186 				      bridge_connector);
187 }
188 
189 static void drm_bridge_connector_disable_hpd(struct drm_connector *connector)
190 {
191 	struct drm_bridge_connector *bridge_connector =
192 		to_drm_bridge_connector(connector);
193 	struct drm_bridge *hpd = bridge_connector->bridge_hpd;
194 
195 	if (hpd)
196 		drm_bridge_hpd_disable(hpd);
197 }
198 
199 /* -----------------------------------------------------------------------------
200  * Bridge Connector Functions
201  */
202 
203 static enum drm_connector_status
204 drm_bridge_connector_detect(struct drm_connector *connector, bool force)
205 {
206 	struct drm_bridge_connector *bridge_connector =
207 		to_drm_bridge_connector(connector);
208 	struct drm_bridge *detect = bridge_connector->bridge_detect;
209 	struct drm_bridge *hdmi = bridge_connector->bridge_hdmi;
210 	enum drm_connector_status status;
211 
212 	if (detect) {
213 		status = detect->funcs->detect(detect, connector);
214 
215 		if (hdmi)
216 			drm_atomic_helper_connector_hdmi_hotplug(connector, status);
217 
218 		drm_bridge_connector_hpd_notify(connector, status);
219 	} else {
220 		switch (connector->connector_type) {
221 		case DRM_MODE_CONNECTOR_DPI:
222 		case DRM_MODE_CONNECTOR_LVDS:
223 		case DRM_MODE_CONNECTOR_DSI:
224 		case DRM_MODE_CONNECTOR_eDP:
225 			status = connector_status_connected;
226 			break;
227 		default:
228 			status = connector_status_unknown;
229 			break;
230 		}
231 	}
232 
233 	return status;
234 }
235 
236 static void drm_bridge_connector_force(struct drm_connector *connector)
237 {
238 	struct drm_bridge_connector *bridge_connector =
239 		to_drm_bridge_connector(connector);
240 	struct drm_bridge *hdmi = bridge_connector->bridge_hdmi;
241 
242 	if (hdmi)
243 		drm_atomic_helper_connector_hdmi_force(connector);
244 }
245 
246 static void drm_bridge_connector_debugfs_init(struct drm_connector *connector,
247 					      struct dentry *root)
248 {
249 	struct drm_bridge_connector *bridge_connector =
250 		to_drm_bridge_connector(connector);
251 	struct drm_encoder *encoder = bridge_connector->encoder;
252 	struct drm_bridge *bridge;
253 
254 	list_for_each_entry(bridge, &encoder->bridge_chain, chain_node) {
255 		if (bridge->funcs->debugfs_init)
256 			bridge->funcs->debugfs_init(bridge, root);
257 	}
258 }
259 
260 static void drm_bridge_connector_reset(struct drm_connector *connector)
261 {
262 	struct drm_bridge_connector *bridge_connector =
263 		to_drm_bridge_connector(connector);
264 
265 	drm_atomic_helper_connector_reset(connector);
266 	if (bridge_connector->bridge_hdmi)
267 		__drm_atomic_helper_connector_hdmi_reset(connector,
268 							 connector->state);
269 }
270 
271 static const struct drm_connector_funcs drm_bridge_connector_funcs = {
272 	.reset = drm_bridge_connector_reset,
273 	.detect = drm_bridge_connector_detect,
274 	.force = drm_bridge_connector_force,
275 	.fill_modes = drm_helper_probe_single_connector_modes,
276 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
277 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
278 	.debugfs_init = drm_bridge_connector_debugfs_init,
279 	.oob_hotplug_event = drm_bridge_connector_oob_hotplug_event,
280 };
281 
282 /* -----------------------------------------------------------------------------
283  * Bridge Connector Helper Functions
284  */
285 
286 static int drm_bridge_connector_get_modes_edid(struct drm_connector *connector,
287 					       struct drm_bridge *bridge)
288 {
289 	enum drm_connector_status status;
290 	const struct drm_edid *drm_edid;
291 	int n;
292 
293 	status = drm_bridge_connector_detect(connector, false);
294 	if (status != connector_status_connected)
295 		goto no_edid;
296 
297 	drm_edid = drm_bridge_edid_read(bridge, connector);
298 	if (!drm_edid_valid(drm_edid)) {
299 		drm_edid_free(drm_edid);
300 		goto no_edid;
301 	}
302 
303 	drm_edid_connector_update(connector, drm_edid);
304 	n = drm_edid_connector_add_modes(connector);
305 
306 	drm_edid_free(drm_edid);
307 	return n;
308 
309 no_edid:
310 	drm_edid_connector_update(connector, NULL);
311 	return 0;
312 }
313 
314 static int drm_bridge_connector_get_modes(struct drm_connector *connector)
315 {
316 	struct drm_bridge_connector *bridge_connector =
317 		to_drm_bridge_connector(connector);
318 	struct drm_bridge *bridge;
319 
320 	/*
321 	 * If there is a HDMI bridge, EDID has been updated as a part of
322 	 * the .detect(). Just update the modes here.
323 	 */
324 	bridge = bridge_connector->bridge_hdmi;
325 	if (bridge)
326 		return drm_edid_connector_add_modes(connector);
327 
328 	/*
329 	 * If display exposes EDID, then we parse that in the normal way to
330 	 * build table of supported modes.
331 	 */
332 	bridge = bridge_connector->bridge_edid;
333 	if (bridge)
334 		return drm_bridge_connector_get_modes_edid(connector, bridge);
335 
336 	/*
337 	 * Otherwise if the display pipeline reports modes (e.g. with a fixed
338 	 * resolution panel or an analog TV output), query it.
339 	 */
340 	bridge = bridge_connector->bridge_modes;
341 	if (bridge)
342 		return bridge->funcs->get_modes(bridge, connector);
343 
344 	/*
345 	 * We can't retrieve modes, which can happen for instance for a DVI or
346 	 * VGA output with the DDC bus unconnected. The KMS core will add the
347 	 * default modes.
348 	 */
349 	return 0;
350 }
351 
352 static enum drm_mode_status
353 drm_bridge_connector_mode_valid(struct drm_connector *connector,
354 				const struct drm_display_mode *mode)
355 {
356 	struct drm_bridge_connector *bridge_connector =
357 		to_drm_bridge_connector(connector);
358 
359 	if (bridge_connector->bridge_hdmi)
360 		return drm_hdmi_connector_mode_valid(connector, mode);
361 
362 	return MODE_OK;
363 }
364 
365 static int drm_bridge_connector_atomic_check(struct drm_connector *connector,
366 					     struct drm_atomic_state *state)
367 {
368 	struct drm_bridge_connector *bridge_connector =
369 		to_drm_bridge_connector(connector);
370 
371 	if (bridge_connector->bridge_hdmi)
372 		return drm_atomic_helper_connector_hdmi_check(connector, state);
373 
374 	return 0;
375 }
376 
377 static const struct drm_connector_helper_funcs drm_bridge_connector_helper_funcs = {
378 	.get_modes = drm_bridge_connector_get_modes,
379 	.mode_valid = drm_bridge_connector_mode_valid,
380 	.enable_hpd = drm_bridge_connector_enable_hpd,
381 	.disable_hpd = drm_bridge_connector_disable_hpd,
382 	.atomic_check = drm_bridge_connector_atomic_check,
383 };
384 
385 static enum drm_mode_status
386 drm_bridge_connector_tmds_char_rate_valid(const struct drm_connector *connector,
387 					  const struct drm_display_mode *mode,
388 					  unsigned long long tmds_rate)
389 {
390 	struct drm_bridge_connector *bridge_connector =
391 		to_drm_bridge_connector(connector);
392 	struct drm_bridge *bridge;
393 
394 	bridge = bridge_connector->bridge_hdmi;
395 	if (!bridge)
396 		return MODE_ERROR;
397 
398 	if (bridge->funcs->hdmi_tmds_char_rate_valid)
399 		return bridge->funcs->hdmi_tmds_char_rate_valid(bridge, mode, tmds_rate);
400 	else
401 		return MODE_OK;
402 }
403 
404 static int drm_bridge_connector_clear_infoframe(struct drm_connector *connector,
405 						enum hdmi_infoframe_type type)
406 {
407 	struct drm_bridge_connector *bridge_connector =
408 		to_drm_bridge_connector(connector);
409 	struct drm_bridge *bridge;
410 
411 	bridge = bridge_connector->bridge_hdmi;
412 	if (!bridge)
413 		return -EINVAL;
414 
415 	return bridge->funcs->hdmi_clear_infoframe(bridge, type);
416 }
417 
418 static int drm_bridge_connector_write_infoframe(struct drm_connector *connector,
419 						enum hdmi_infoframe_type type,
420 						const u8 *buffer, size_t len)
421 {
422 	struct drm_bridge_connector *bridge_connector =
423 		to_drm_bridge_connector(connector);
424 	struct drm_bridge *bridge;
425 
426 	bridge = bridge_connector->bridge_hdmi;
427 	if (!bridge)
428 		return -EINVAL;
429 
430 	return bridge->funcs->hdmi_write_infoframe(bridge, type, buffer, len);
431 }
432 
433 static const struct drm_edid *
434 drm_bridge_connector_read_edid(struct drm_connector *connector)
435 {
436 	struct drm_bridge_connector *bridge_connector =
437 		to_drm_bridge_connector(connector);
438 	struct drm_bridge *bridge;
439 
440 	bridge = bridge_connector->bridge_edid;
441 	if (!bridge)
442 		return NULL;
443 
444 	return drm_bridge_edid_read(bridge, connector);
445 }
446 
447 static const struct drm_connector_hdmi_funcs drm_bridge_connector_hdmi_funcs = {
448 	.tmds_char_rate_valid = drm_bridge_connector_tmds_char_rate_valid,
449 	.clear_infoframe = drm_bridge_connector_clear_infoframe,
450 	.write_infoframe = drm_bridge_connector_write_infoframe,
451 	.read_edid = drm_bridge_connector_read_edid,
452 };
453 
454 static int drm_bridge_connector_audio_startup(struct drm_connector *connector)
455 {
456 	struct drm_bridge_connector *bridge_connector =
457 		to_drm_bridge_connector(connector);
458 	struct drm_bridge *bridge;
459 
460 	if (bridge_connector->bridge_hdmi_audio) {
461 		bridge = bridge_connector->bridge_hdmi_audio;
462 
463 		if (!bridge->funcs->hdmi_audio_startup)
464 			return 0;
465 
466 		return bridge->funcs->hdmi_audio_startup(bridge, connector);
467 	}
468 
469 	if (bridge_connector->bridge_dp_audio) {
470 		bridge = bridge_connector->bridge_dp_audio;
471 
472 		if (!bridge->funcs->dp_audio_startup)
473 			return 0;
474 
475 		return bridge->funcs->dp_audio_startup(bridge, connector);
476 	}
477 
478 	return -EINVAL;
479 }
480 
481 static int drm_bridge_connector_audio_prepare(struct drm_connector *connector,
482 					      struct hdmi_codec_daifmt *fmt,
483 					      struct hdmi_codec_params *hparms)
484 {
485 	struct drm_bridge_connector *bridge_connector =
486 		to_drm_bridge_connector(connector);
487 	struct drm_bridge *bridge;
488 
489 	if (bridge_connector->bridge_hdmi_audio) {
490 		bridge = bridge_connector->bridge_hdmi_audio;
491 
492 		return bridge->funcs->hdmi_audio_prepare(bridge, connector, fmt, hparms);
493 	}
494 
495 	if (bridge_connector->bridge_dp_audio) {
496 		bridge = bridge_connector->bridge_dp_audio;
497 
498 		return bridge->funcs->dp_audio_prepare(bridge, connector, fmt, hparms);
499 	}
500 
501 	return -EINVAL;
502 }
503 
504 static void drm_bridge_connector_audio_shutdown(struct drm_connector *connector)
505 {
506 	struct drm_bridge_connector *bridge_connector =
507 		to_drm_bridge_connector(connector);
508 	struct drm_bridge *bridge;
509 
510 	if (bridge_connector->bridge_hdmi_audio) {
511 		bridge = bridge_connector->bridge_hdmi_audio;
512 		bridge->funcs->hdmi_audio_shutdown(bridge, connector);
513 	}
514 
515 	if (bridge_connector->bridge_dp_audio) {
516 		bridge = bridge_connector->bridge_dp_audio;
517 		bridge->funcs->dp_audio_shutdown(bridge, connector);
518 	}
519 }
520 
521 static int drm_bridge_connector_audio_mute_stream(struct drm_connector *connector,
522 						  bool enable, int direction)
523 {
524 	struct drm_bridge_connector *bridge_connector =
525 		to_drm_bridge_connector(connector);
526 	struct drm_bridge *bridge;
527 
528 	if (bridge_connector->bridge_hdmi_audio) {
529 		bridge = bridge_connector->bridge_hdmi_audio;
530 
531 		if (!bridge->funcs->hdmi_audio_mute_stream)
532 			return -ENOTSUPP;
533 
534 		return bridge->funcs->hdmi_audio_mute_stream(bridge, connector,
535 							     enable, direction);
536 	}
537 
538 	if (bridge_connector->bridge_dp_audio) {
539 		bridge = bridge_connector->bridge_dp_audio;
540 
541 		if (!bridge->funcs->dp_audio_mute_stream)
542 			return -ENOTSUPP;
543 
544 		return bridge->funcs->dp_audio_mute_stream(bridge, connector,
545 							   enable, direction);
546 	}
547 
548 	return -EINVAL;
549 }
550 
551 static const struct drm_connector_hdmi_audio_funcs drm_bridge_connector_hdmi_audio_funcs = {
552 	.startup = drm_bridge_connector_audio_startup,
553 	.prepare = drm_bridge_connector_audio_prepare,
554 	.shutdown = drm_bridge_connector_audio_shutdown,
555 	.mute_stream = drm_bridge_connector_audio_mute_stream,
556 };
557 
558 static int drm_bridge_connector_hdmi_cec_enable(struct drm_connector *connector, bool enable)
559 {
560 	struct drm_bridge_connector *bridge_connector =
561 		to_drm_bridge_connector(connector);
562 	struct drm_bridge *bridge;
563 
564 	bridge = bridge_connector->bridge_hdmi_cec;
565 
566 	return bridge->funcs->hdmi_cec_enable(bridge, enable);
567 }
568 
569 static int drm_bridge_connector_hdmi_cec_log_addr(struct drm_connector *connector, u8 logical_addr)
570 {
571 	struct drm_bridge_connector *bridge_connector =
572 		to_drm_bridge_connector(connector);
573 	struct drm_bridge *bridge;
574 
575 	bridge = bridge_connector->bridge_hdmi_cec;
576 
577 	return bridge->funcs->hdmi_cec_log_addr(bridge, logical_addr);
578 }
579 
580 static int drm_bridge_connector_hdmi_cec_transmit(struct drm_connector *connector,
581 						  u8 attempts,
582 						  u32 signal_free_time,
583 						  struct cec_msg *msg)
584 {
585 	struct drm_bridge_connector *bridge_connector =
586 		to_drm_bridge_connector(connector);
587 	struct drm_bridge *bridge;
588 
589 	bridge = bridge_connector->bridge_hdmi_cec;
590 
591 	return bridge->funcs->hdmi_cec_transmit(bridge, attempts,
592 						signal_free_time,
593 						msg);
594 }
595 
596 static int drm_bridge_connector_hdmi_cec_init(struct drm_connector *connector)
597 {
598 	struct drm_bridge_connector *bridge_connector =
599 		to_drm_bridge_connector(connector);
600 	struct drm_bridge *bridge;
601 
602 	bridge = bridge_connector->bridge_hdmi_cec;
603 
604 	if (!bridge->funcs->hdmi_cec_init)
605 		return 0;
606 
607 	return bridge->funcs->hdmi_cec_init(bridge, connector);
608 }
609 
610 static const struct drm_connector_hdmi_cec_funcs drm_bridge_connector_hdmi_cec_funcs = {
611 	.init = drm_bridge_connector_hdmi_cec_init,
612 	.enable = drm_bridge_connector_hdmi_cec_enable,
613 	.log_addr = drm_bridge_connector_hdmi_cec_log_addr,
614 	.transmit = drm_bridge_connector_hdmi_cec_transmit,
615 };
616 
617 /* -----------------------------------------------------------------------------
618  * Bridge Connector Initialisation
619  */
620 
621 static void drm_bridge_connector_put_bridges(struct drm_device *dev, void *data)
622 {
623 	struct drm_bridge_connector *bridge_connector = (struct drm_bridge_connector *)data;
624 
625 	drm_bridge_put(bridge_connector->bridge_edid);
626 	drm_bridge_put(bridge_connector->bridge_hpd);
627 	drm_bridge_put(bridge_connector->bridge_detect);
628 	drm_bridge_put(bridge_connector->bridge_modes);
629 	drm_bridge_put(bridge_connector->bridge_hdmi);
630 	drm_bridge_put(bridge_connector->bridge_hdmi_audio);
631 	drm_bridge_put(bridge_connector->bridge_dp_audio);
632 	drm_bridge_put(bridge_connector->bridge_hdmi_cec);
633 }
634 
635 /**
636  * drm_bridge_connector_init - Initialise a connector for a chain of bridges
637  * @drm: the DRM device
638  * @encoder: the encoder where the bridge chain starts
639  *
640  * Allocate, initialise and register a &drm_bridge_connector with the @drm
641  * device. The connector is associated with a chain of bridges that starts at
642  * the @encoder. All bridges in the chain shall report bridge operation flags
643  * (&drm_bridge->ops) and bridge output type (&drm_bridge->type), and none of
644  * them may create a DRM connector directly.
645  *
646  * Returns a pointer to the new connector on success, or a negative error
647  * pointer otherwise.
648  */
649 struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
650 						struct drm_encoder *encoder)
651 {
652 	struct drm_bridge_connector *bridge_connector;
653 	struct drm_connector *connector;
654 	struct i2c_adapter *ddc = NULL;
655 	struct drm_bridge *panel_bridge __free(drm_bridge_put) = NULL;
656 	unsigned int supported_formats = BIT(HDMI_COLORSPACE_RGB);
657 	unsigned int max_bpc = 8;
658 	bool support_hdcp = false;
659 	int connector_type;
660 	int ret;
661 
662 	bridge_connector = drmm_kzalloc(drm, sizeof(*bridge_connector), GFP_KERNEL);
663 	if (!bridge_connector)
664 		return ERR_PTR(-ENOMEM);
665 
666 	ret = drmm_add_action(drm, drm_bridge_connector_put_bridges, bridge_connector);
667 	if (ret)
668 		return ERR_PTR(ret);
669 
670 	bridge_connector->encoder = encoder;
671 
672 	/*
673 	 * TODO: Handle doublescan_allowed and stereo_allowed.
674 	 */
675 	connector = &bridge_connector->base;
676 	connector->interlace_allowed = true;
677 	connector->ycbcr_420_allowed = true;
678 
679 	/*
680 	 * Initialise connector status handling. First locate the furthest
681 	 * bridges in the pipeline that support HPD and output detection. Then
682 	 * initialise the connector polling mode, using HPD if available and
683 	 * falling back to polling if supported. If neither HPD nor output
684 	 * detection are available, we don't support hotplug detection at all.
685 	 */
686 	connector_type = DRM_MODE_CONNECTOR_Unknown;
687 	drm_for_each_bridge_in_chain_scoped(encoder, bridge) {
688 		if (!bridge->interlace_allowed)
689 			connector->interlace_allowed = false;
690 		if (!bridge->ycbcr_420_allowed)
691 			connector->ycbcr_420_allowed = false;
692 
693 		if (bridge->ops & DRM_BRIDGE_OP_EDID) {
694 			drm_bridge_put(bridge_connector->bridge_edid);
695 			bridge_connector->bridge_edid = drm_bridge_get(bridge);
696 		}
697 		if (bridge->ops & DRM_BRIDGE_OP_HPD) {
698 			drm_bridge_put(bridge_connector->bridge_hpd);
699 			bridge_connector->bridge_hpd = drm_bridge_get(bridge);
700 		}
701 		if (bridge->ops & DRM_BRIDGE_OP_DETECT) {
702 			drm_bridge_put(bridge_connector->bridge_detect);
703 			bridge_connector->bridge_detect = drm_bridge_get(bridge);
704 		}
705 		if (bridge->ops & DRM_BRIDGE_OP_MODES) {
706 			drm_bridge_put(bridge_connector->bridge_modes);
707 			bridge_connector->bridge_modes = drm_bridge_get(bridge);
708 		}
709 		if (bridge->ops & DRM_BRIDGE_OP_HDMI) {
710 			if (bridge_connector->bridge_hdmi)
711 				return ERR_PTR(-EBUSY);
712 			if (!bridge->funcs->hdmi_write_infoframe ||
713 			    !bridge->funcs->hdmi_clear_infoframe)
714 				return ERR_PTR(-EINVAL);
715 
716 			bridge_connector->bridge_hdmi = drm_bridge_get(bridge);
717 
718 			if (bridge->supported_formats)
719 				supported_formats = bridge->supported_formats;
720 			if (bridge->max_bpc)
721 				max_bpc = bridge->max_bpc;
722 		}
723 
724 		if (bridge->ops & DRM_BRIDGE_OP_HDMI_AUDIO) {
725 			if (bridge_connector->bridge_hdmi_audio)
726 				return ERR_PTR(-EBUSY);
727 
728 			if (bridge_connector->bridge_dp_audio)
729 				return ERR_PTR(-EBUSY);
730 
731 			if (!bridge->hdmi_audio_max_i2s_playback_channels &&
732 			    !bridge->hdmi_audio_spdif_playback)
733 				return ERR_PTR(-EINVAL);
734 
735 			if (!bridge->funcs->hdmi_audio_prepare ||
736 			    !bridge->funcs->hdmi_audio_shutdown)
737 				return ERR_PTR(-EINVAL);
738 
739 			bridge_connector->bridge_hdmi_audio = drm_bridge_get(bridge);
740 		}
741 
742 		if (bridge->ops & DRM_BRIDGE_OP_DP_AUDIO) {
743 			if (bridge_connector->bridge_dp_audio)
744 				return ERR_PTR(-EBUSY);
745 
746 			if (bridge_connector->bridge_hdmi_audio)
747 				return ERR_PTR(-EBUSY);
748 
749 			if (!bridge->hdmi_audio_max_i2s_playback_channels &&
750 			    !bridge->hdmi_audio_spdif_playback)
751 				return ERR_PTR(-EINVAL);
752 
753 			if (!bridge->funcs->dp_audio_prepare ||
754 			    !bridge->funcs->dp_audio_shutdown)
755 				return ERR_PTR(-EINVAL);
756 
757 			bridge_connector->bridge_dp_audio = drm_bridge_get(bridge);
758 		}
759 
760 		if (bridge->ops & DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER) {
761 			if (bridge_connector->bridge_hdmi_cec)
762 				return ERR_PTR(-EBUSY);
763 
764 			bridge_connector->bridge_hdmi_cec = drm_bridge_get(bridge);
765 		}
766 
767 		if (bridge->ops & DRM_BRIDGE_OP_HDMI_CEC_ADAPTER) {
768 			if (bridge_connector->bridge_hdmi_cec)
769 				return ERR_PTR(-EBUSY);
770 
771 			bridge_connector->bridge_hdmi_cec = drm_bridge_get(bridge);
772 
773 			if (!bridge->funcs->hdmi_cec_enable ||
774 			    !bridge->funcs->hdmi_cec_log_addr ||
775 			    !bridge->funcs->hdmi_cec_transmit)
776 				return ERR_PTR(-EINVAL);
777 		}
778 
779 		if (drm_bridge_is_last(bridge))
780 			connector_type = bridge->type;
781 
782 #ifdef CONFIG_OF
783 		if (drm_bridge_is_last(bridge) && bridge->of_node)
784 			connector->fwnode = fwnode_handle_get(of_fwnode_handle(bridge->of_node));
785 #endif
786 
787 		if (bridge->ddc)
788 			ddc = bridge->ddc;
789 
790 		if (drm_bridge_is_panel(bridge)) {
791 			drm_bridge_put(panel_bridge);
792 			panel_bridge = drm_bridge_get(bridge);
793 		}
794 
795 		if (bridge->support_hdcp)
796 			support_hdcp = true;
797 	}
798 
799 	if (connector_type == DRM_MODE_CONNECTOR_Unknown)
800 		return ERR_PTR(-EINVAL);
801 
802 	if (bridge_connector->bridge_hdmi) {
803 		if (!connector->ycbcr_420_allowed)
804 			supported_formats &= ~BIT(HDMI_COLORSPACE_YUV420);
805 
806 		ret = drmm_connector_hdmi_init(drm, connector,
807 					       bridge_connector->bridge_hdmi->vendor,
808 					       bridge_connector->bridge_hdmi->product,
809 					       &drm_bridge_connector_funcs,
810 					       &drm_bridge_connector_hdmi_funcs,
811 					       connector_type, ddc,
812 					       supported_formats,
813 					       max_bpc);
814 		if (ret)
815 			return ERR_PTR(ret);
816 	} else {
817 		ret = drmm_connector_init(drm, connector,
818 					  &drm_bridge_connector_funcs,
819 					  connector_type, ddc);
820 		if (ret)
821 			return ERR_PTR(ret);
822 	}
823 
824 	if (bridge_connector->bridge_hdmi_audio ||
825 	    bridge_connector->bridge_dp_audio) {
826 		struct device *dev;
827 		struct drm_bridge *bridge;
828 
829 		if (bridge_connector->bridge_hdmi_audio)
830 			bridge = bridge_connector->bridge_hdmi_audio;
831 		else
832 			bridge = bridge_connector->bridge_dp_audio;
833 
834 		dev = bridge->hdmi_audio_dev;
835 
836 		ret = drm_connector_hdmi_audio_init(connector, dev,
837 						    &drm_bridge_connector_hdmi_audio_funcs,
838 						    bridge->hdmi_audio_max_i2s_playback_channels,
839 						    bridge->hdmi_audio_i2s_formats,
840 						    bridge->hdmi_audio_spdif_playback,
841 						    bridge->hdmi_audio_dai_port);
842 		if (ret)
843 			return ERR_PTR(ret);
844 	}
845 
846 	if (bridge_connector->bridge_hdmi_cec &&
847 	    bridge_connector->bridge_hdmi_cec->ops & DRM_BRIDGE_OP_HDMI_CEC_NOTIFIER) {
848 		struct drm_bridge *bridge = bridge_connector->bridge_hdmi_cec;
849 
850 		ret = drmm_connector_hdmi_cec_notifier_register(connector,
851 								NULL,
852 								bridge->hdmi_cec_dev);
853 		if (ret)
854 			return ERR_PTR(ret);
855 	}
856 
857 	if (bridge_connector->bridge_hdmi_cec &&
858 	    bridge_connector->bridge_hdmi_cec->ops & DRM_BRIDGE_OP_HDMI_CEC_ADAPTER) {
859 		struct drm_bridge *bridge = bridge_connector->bridge_hdmi_cec;
860 
861 		ret = drmm_connector_hdmi_cec_register(connector,
862 						       &drm_bridge_connector_hdmi_cec_funcs,
863 						       bridge->hdmi_cec_adapter_name,
864 						       bridge->hdmi_cec_available_las,
865 						       bridge->hdmi_cec_dev);
866 		if (ret)
867 			return ERR_PTR(ret);
868 	}
869 
870 	drm_connector_helper_add(connector, &drm_bridge_connector_helper_funcs);
871 
872 	if (bridge_connector->bridge_hpd)
873 		connector->polled = DRM_CONNECTOR_POLL_HPD;
874 	else if (bridge_connector->bridge_detect)
875 		connector->polled = DRM_CONNECTOR_POLL_CONNECT
876 				  | DRM_CONNECTOR_POLL_DISCONNECT;
877 
878 	if (panel_bridge)
879 		drm_panel_bridge_set_orientation(connector, panel_bridge);
880 
881 	if (support_hdcp && IS_REACHABLE(CONFIG_DRM_DISPLAY_HELPER) &&
882 	    IS_ENABLED(CONFIG_DRM_DISPLAY_HDCP_HELPER))
883 		drm_connector_attach_content_protection_property(connector, true);
884 
885 	return connector;
886 }
887 EXPORT_SYMBOL_GPL(drm_bridge_connector_init);
888