Line data Source code
1 : /*
2 : * Copyright (c) 2016 Intel Corporation
3 : *
4 : * Permission to use, copy, modify, distribute, and sell this software and its
5 : * documentation for any purpose is hereby granted without fee, provided that
6 : * the above copyright notice appear in all copies and that both that copyright
7 : * notice and this permission notice appear in supporting documentation, and
8 : * that the name of the copyright holders not be used in advertising or
9 : * publicity pertaining to distribution of the software without specific,
10 : * written prior permission. The copyright holders make no representations
11 : * about the suitability of this software for any purpose. It is provided "as
12 : * is" without express or implied warranty.
13 : *
14 : * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 : * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 : * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 : * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 : * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 : * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 : * OF THIS SOFTWARE.
21 : */
22 :
23 : #ifndef __DRM_BRIDGE_H__
24 : #define __DRM_BRIDGE_H__
25 :
26 : #include <linux/ctype.h>
27 : #include <linux/list.h>
28 : #include <linux/mutex.h>
29 :
30 : #include <drm/drm_atomic.h>
31 : #include <drm/drm_encoder.h>
32 : #include <drm/drm_mode_object.h>
33 : #include <drm/drm_modes.h>
34 :
35 : struct drm_bridge;
36 : struct drm_bridge_timings;
37 : struct drm_connector;
38 : struct drm_display_info;
39 : struct drm_minor;
40 : struct drm_panel;
41 : struct edid;
42 : struct i2c_adapter;
43 :
44 : /**
45 : * enum drm_bridge_attach_flags - Flags for &drm_bridge_funcs.attach
46 : */
47 : enum drm_bridge_attach_flags {
48 : /**
49 : * @DRM_BRIDGE_ATTACH_NO_CONNECTOR: When this flag is set the bridge
50 : * shall not create a drm_connector.
51 : */
52 : DRM_BRIDGE_ATTACH_NO_CONNECTOR = BIT(0),
53 : };
54 :
55 : /**
56 : * struct drm_bridge_funcs - drm_bridge control functions
57 : */
58 : struct drm_bridge_funcs {
59 : /**
60 : * @attach:
61 : *
62 : * This callback is invoked whenever our bridge is being attached to a
63 : * &drm_encoder. The flags argument tunes the behaviour of the attach
64 : * operation (see DRM_BRIDGE_ATTACH_*).
65 : *
66 : * The @attach callback is optional.
67 : *
68 : * RETURNS:
69 : *
70 : * Zero on success, error code on failure.
71 : */
72 : int (*attach)(struct drm_bridge *bridge,
73 : enum drm_bridge_attach_flags flags);
74 :
75 : /**
76 : * @detach:
77 : *
78 : * This callback is invoked whenever our bridge is being detached from a
79 : * &drm_encoder.
80 : *
81 : * The @detach callback is optional.
82 : */
83 : void (*detach)(struct drm_bridge *bridge);
84 :
85 : /**
86 : * @mode_valid:
87 : *
88 : * This callback is used to check if a specific mode is valid in this
89 : * bridge. This should be implemented if the bridge has some sort of
90 : * restriction in the modes it can display. For example, a given bridge
91 : * may be responsible to set a clock value. If the clock can not
92 : * produce all the values for the available modes then this callback
93 : * can be used to restrict the number of modes to only the ones that
94 : * can be displayed.
95 : *
96 : * This hook is used by the probe helpers to filter the mode list in
97 : * drm_helper_probe_single_connector_modes(), and it is used by the
98 : * atomic helpers to validate modes supplied by userspace in
99 : * drm_atomic_helper_check_modeset().
100 : *
101 : * The @mode_valid callback is optional.
102 : *
103 : * NOTE:
104 : *
105 : * Since this function is both called from the check phase of an atomic
106 : * commit, and the mode validation in the probe paths it is not allowed
107 : * to look at anything else but the passed-in mode, and validate it
108 : * against configuration-invariant hardward constraints. Any further
109 : * limits which depend upon the configuration can only be checked in
110 : * @mode_fixup.
111 : *
112 : * RETURNS:
113 : *
114 : * drm_mode_status Enum
115 : */
116 : enum drm_mode_status (*mode_valid)(struct drm_bridge *bridge,
117 : const struct drm_display_info *info,
118 : const struct drm_display_mode *mode);
119 :
120 : /**
121 : * @mode_fixup:
122 : *
123 : * This callback is used to validate and adjust a mode. The parameter
124 : * mode is the display mode that should be fed to the next element in
125 : * the display chain, either the final &drm_connector or the next
126 : * &drm_bridge. The parameter adjusted_mode is the input mode the bridge
127 : * requires. It can be modified by this callback and does not need to
128 : * match mode. See also &drm_crtc_state.adjusted_mode for more details.
129 : *
130 : * This is the only hook that allows a bridge to reject a modeset. If
131 : * this function passes all other callbacks must succeed for this
132 : * configuration.
133 : *
134 : * The mode_fixup callback is optional. &drm_bridge_funcs.mode_fixup()
135 : * is not called when &drm_bridge_funcs.atomic_check() is implemented,
136 : * so only one of them should be provided.
137 : *
138 : * NOTE:
139 : *
140 : * This function is called in the check phase of atomic modesets, which
141 : * can be aborted for any reason (including on userspace's request to
142 : * just check whether a configuration would be possible). Drivers MUST
143 : * NOT touch any persistent state (hardware or software) or data
144 : * structures except the passed in @state parameter.
145 : *
146 : * Also beware that userspace can request its own custom modes, neither
147 : * core nor helpers filter modes to the list of probe modes reported by
148 : * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
149 : * that modes are filtered consistently put any bridge constraints and
150 : * limits checks into @mode_valid.
151 : *
152 : * RETURNS:
153 : *
154 : * True if an acceptable configuration is possible, false if the modeset
155 : * operation should be rejected.
156 : */
157 : bool (*mode_fixup)(struct drm_bridge *bridge,
158 : const struct drm_display_mode *mode,
159 : struct drm_display_mode *adjusted_mode);
160 : /**
161 : * @disable:
162 : *
163 : * This callback should disable the bridge. It is called right before
164 : * the preceding element in the display pipe is disabled. If the
165 : * preceding element is a bridge this means it's called before that
166 : * bridge's @disable vfunc. If the preceding element is a &drm_encoder
167 : * it's called right before the &drm_encoder_helper_funcs.disable,
168 : * &drm_encoder_helper_funcs.prepare or &drm_encoder_helper_funcs.dpms
169 : * hook.
170 : *
171 : * The bridge can assume that the display pipe (i.e. clocks and timing
172 : * signals) feeding it is still running when this callback is called.
173 : *
174 : * The @disable callback is optional.
175 : *
176 : * NOTE:
177 : *
178 : * This is deprecated, do not use!
179 : * New drivers shall use &drm_bridge_funcs.atomic_disable.
180 : */
181 : void (*disable)(struct drm_bridge *bridge);
182 :
183 : /**
184 : * @post_disable:
185 : *
186 : * This callback should disable the bridge. It is called right after the
187 : * preceding element in the display pipe is disabled. If the preceding
188 : * element is a bridge this means it's called after that bridge's
189 : * @post_disable function. If the preceding element is a &drm_encoder
190 : * it's called right after the encoder's
191 : * &drm_encoder_helper_funcs.disable, &drm_encoder_helper_funcs.prepare
192 : * or &drm_encoder_helper_funcs.dpms hook.
193 : *
194 : * The bridge must assume that the display pipe (i.e. clocks and timing
195 : * singals) feeding it is no longer running when this callback is
196 : * called.
197 : *
198 : * The @post_disable callback is optional.
199 : *
200 : * NOTE:
201 : *
202 : * This is deprecated, do not use!
203 : * New drivers shall use &drm_bridge_funcs.atomic_post_disable.
204 : */
205 : void (*post_disable)(struct drm_bridge *bridge);
206 :
207 : /**
208 : * @mode_set:
209 : *
210 : * This callback should set the given mode on the bridge. It is called
211 : * after the @mode_set callback for the preceding element in the display
212 : * pipeline has been called already. If the bridge is the first element
213 : * then this would be &drm_encoder_helper_funcs.mode_set. The display
214 : * pipe (i.e. clocks and timing signals) is off when this function is
215 : * called.
216 : *
217 : * The adjusted_mode parameter is the mode output by the CRTC for the
218 : * first bridge in the chain. It can be different from the mode
219 : * parameter that contains the desired mode for the connector at the end
220 : * of the bridges chain, for instance when the first bridge in the chain
221 : * performs scaling. The adjusted mode is mostly useful for the first
222 : * bridge in the chain and is likely irrelevant for the other bridges.
223 : *
224 : * For atomic drivers the adjusted_mode is the mode stored in
225 : * &drm_crtc_state.adjusted_mode.
226 : *
227 : * NOTE:
228 : *
229 : * This is deprecated, do not use!
230 : * New drivers shall set their mode in the
231 : * &drm_bridge_funcs.atomic_enable operation.
232 : */
233 : void (*mode_set)(struct drm_bridge *bridge,
234 : const struct drm_display_mode *mode,
235 : const struct drm_display_mode *adjusted_mode);
236 : /**
237 : * @pre_enable:
238 : *
239 : * This callback should enable the bridge. It is called right before
240 : * the preceding element in the display pipe is enabled. If the
241 : * preceding element is a bridge this means it's called before that
242 : * bridge's @pre_enable function. If the preceding element is a
243 : * &drm_encoder it's called right before the encoder's
244 : * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or
245 : * &drm_encoder_helper_funcs.dpms hook.
246 : *
247 : * The display pipe (i.e. clocks and timing signals) feeding this bridge
248 : * will not yet be running when this callback is called. The bridge must
249 : * not enable the display link feeding the next bridge in the chain (if
250 : * there is one) when this callback is called.
251 : *
252 : * The @pre_enable callback is optional.
253 : *
254 : * NOTE:
255 : *
256 : * This is deprecated, do not use!
257 : * New drivers shall use &drm_bridge_funcs.atomic_pre_enable.
258 : */
259 : void (*pre_enable)(struct drm_bridge *bridge);
260 :
261 : /**
262 : * @enable:
263 : *
264 : * This callback should enable the bridge. It is called right after
265 : * the preceding element in the display pipe is enabled. If the
266 : * preceding element is a bridge this means it's called after that
267 : * bridge's @enable function. If the preceding element is a
268 : * &drm_encoder it's called right after the encoder's
269 : * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or
270 : * &drm_encoder_helper_funcs.dpms hook.
271 : *
272 : * The bridge can assume that the display pipe (i.e. clocks and timing
273 : * signals) feeding it is running when this callback is called. This
274 : * callback must enable the display link feeding the next bridge in the
275 : * chain if there is one.
276 : *
277 : * The @enable callback is optional.
278 : *
279 : * NOTE:
280 : *
281 : * This is deprecated, do not use!
282 : * New drivers shall use &drm_bridge_funcs.atomic_enable.
283 : */
284 : void (*enable)(struct drm_bridge *bridge);
285 :
286 : /**
287 : * @atomic_pre_enable:
288 : *
289 : * This callback should enable the bridge. It is called right before
290 : * the preceding element in the display pipe is enabled. If the
291 : * preceding element is a bridge this means it's called before that
292 : * bridge's @atomic_pre_enable or @pre_enable function. If the preceding
293 : * element is a &drm_encoder it's called right before the encoder's
294 : * &drm_encoder_helper_funcs.atomic_enable hook.
295 : *
296 : * The display pipe (i.e. clocks and timing signals) feeding this bridge
297 : * will not yet be running when this callback is called. The bridge must
298 : * not enable the display link feeding the next bridge in the chain (if
299 : * there is one) when this callback is called.
300 : *
301 : * The @atomic_pre_enable callback is optional.
302 : */
303 : void (*atomic_pre_enable)(struct drm_bridge *bridge,
304 : struct drm_bridge_state *old_bridge_state);
305 :
306 : /**
307 : * @atomic_enable:
308 : *
309 : * This callback should enable the bridge. It is called right after
310 : * the preceding element in the display pipe is enabled. If the
311 : * preceding element is a bridge this means it's called after that
312 : * bridge's @atomic_enable or @enable function. If the preceding element
313 : * is a &drm_encoder it's called right after the encoder's
314 : * &drm_encoder_helper_funcs.atomic_enable hook.
315 : *
316 : * The bridge can assume that the display pipe (i.e. clocks and timing
317 : * signals) feeding it is running when this callback is called. This
318 : * callback must enable the display link feeding the next bridge in the
319 : * chain if there is one.
320 : *
321 : * The @atomic_enable callback is optional.
322 : */
323 : void (*atomic_enable)(struct drm_bridge *bridge,
324 : struct drm_bridge_state *old_bridge_state);
325 : /**
326 : * @atomic_disable:
327 : *
328 : * This callback should disable the bridge. It is called right before
329 : * the preceding element in the display pipe is disabled. If the
330 : * preceding element is a bridge this means it's called before that
331 : * bridge's @atomic_disable or @disable vfunc. If the preceding element
332 : * is a &drm_encoder it's called right before the
333 : * &drm_encoder_helper_funcs.atomic_disable hook.
334 : *
335 : * The bridge can assume that the display pipe (i.e. clocks and timing
336 : * signals) feeding it is still running when this callback is called.
337 : *
338 : * The @atomic_disable callback is optional.
339 : */
340 : void (*atomic_disable)(struct drm_bridge *bridge,
341 : struct drm_bridge_state *old_bridge_state);
342 :
343 : /**
344 : * @atomic_post_disable:
345 : *
346 : * This callback should disable the bridge. It is called right after the
347 : * preceding element in the display pipe is disabled. If the preceding
348 : * element is a bridge this means it's called after that bridge's
349 : * @atomic_post_disable or @post_disable function. If the preceding
350 : * element is a &drm_encoder it's called right after the encoder's
351 : * &drm_encoder_helper_funcs.atomic_disable hook.
352 : *
353 : * The bridge must assume that the display pipe (i.e. clocks and timing
354 : * signals) feeding it is no longer running when this callback is
355 : * called.
356 : *
357 : * The @atomic_post_disable callback is optional.
358 : */
359 : void (*atomic_post_disable)(struct drm_bridge *bridge,
360 : struct drm_bridge_state *old_bridge_state);
361 :
362 : /**
363 : * @atomic_duplicate_state:
364 : *
365 : * Duplicate the current bridge state object (which is guaranteed to be
366 : * non-NULL).
367 : *
368 : * The atomic_duplicate_state hook is mandatory if the bridge
369 : * implements any of the atomic hooks, and should be left unassigned
370 : * otherwise. For bridges that don't subclass &drm_bridge_state, the
371 : * drm_atomic_helper_bridge_duplicate_state() helper function shall be
372 : * used to implement this hook.
373 : *
374 : * RETURNS:
375 : * A valid drm_bridge_state object or NULL if the allocation fails.
376 : */
377 : struct drm_bridge_state *(*atomic_duplicate_state)(struct drm_bridge *bridge);
378 :
379 : /**
380 : * @atomic_destroy_state:
381 : *
382 : * Destroy a bridge state object previously allocated by
383 : * &drm_bridge_funcs.atomic_duplicate_state().
384 : *
385 : * The atomic_destroy_state hook is mandatory if the bridge implements
386 : * any of the atomic hooks, and should be left unassigned otherwise.
387 : * For bridges that don't subclass &drm_bridge_state, the
388 : * drm_atomic_helper_bridge_destroy_state() helper function shall be
389 : * used to implement this hook.
390 : */
391 : void (*atomic_destroy_state)(struct drm_bridge *bridge,
392 : struct drm_bridge_state *state);
393 :
394 : /**
395 : * @atomic_get_output_bus_fmts:
396 : *
397 : * Return the supported bus formats on the output end of a bridge.
398 : * The returned array must be allocated with kmalloc() and will be
399 : * freed by the caller. If the allocation fails, NULL should be
400 : * returned. num_output_fmts must be set to the returned array size.
401 : * Formats listed in the returned array should be listed in decreasing
402 : * preference order (the core will try all formats until it finds one
403 : * that works).
404 : *
405 : * This method is only called on the last element of the bridge chain
406 : * as part of the bus format negotiation process that happens in
407 : * &drm_atomic_bridge_chain_select_bus_fmts().
408 : * This method is optional. When not implemented, the core will
409 : * fall back to &drm_connector.display_info.bus_formats[0] if
410 : * &drm_connector.display_info.num_bus_formats > 0,
411 : * or to MEDIA_BUS_FMT_FIXED otherwise.
412 : */
413 : u32 *(*atomic_get_output_bus_fmts)(struct drm_bridge *bridge,
414 : struct drm_bridge_state *bridge_state,
415 : struct drm_crtc_state *crtc_state,
416 : struct drm_connector_state *conn_state,
417 : unsigned int *num_output_fmts);
418 :
419 : /**
420 : * @atomic_get_input_bus_fmts:
421 : *
422 : * Return the supported bus formats on the input end of a bridge for
423 : * a specific output bus format.
424 : *
425 : * The returned array must be allocated with kmalloc() and will be
426 : * freed by the caller. If the allocation fails, NULL should be
427 : * returned. num_input_fmts must be set to the returned array size.
428 : * Formats listed in the returned array should be listed in decreasing
429 : * preference order (the core will try all formats until it finds one
430 : * that works). When the format is not supported NULL should be
431 : * returned and num_input_fmts should be set to 0.
432 : *
433 : * This method is called on all elements of the bridge chain as part of
434 : * the bus format negotiation process that happens in
435 : * drm_atomic_bridge_chain_select_bus_fmts().
436 : * This method is optional. When not implemented, the core will bypass
437 : * bus format negotiation on this element of the bridge without
438 : * failing, and the previous element in the chain will be passed
439 : * MEDIA_BUS_FMT_FIXED as its output bus format.
440 : *
441 : * Bridge drivers that need to support being linked to bridges that are
442 : * not supporting bus format negotiation should handle the
443 : * output_fmt == MEDIA_BUS_FMT_FIXED case appropriately, by selecting a
444 : * sensible default value or extracting this information from somewhere
445 : * else (FW property, &drm_display_mode, &drm_display_info, ...)
446 : *
447 : * Note: Even if input format selection on the first bridge has no
448 : * impact on the negotiation process (bus format negotiation stops once
449 : * we reach the first element of the chain), drivers are expected to
450 : * return accurate input formats as the input format may be used to
451 : * configure the CRTC output appropriately.
452 : */
453 : u32 *(*atomic_get_input_bus_fmts)(struct drm_bridge *bridge,
454 : struct drm_bridge_state *bridge_state,
455 : struct drm_crtc_state *crtc_state,
456 : struct drm_connector_state *conn_state,
457 : u32 output_fmt,
458 : unsigned int *num_input_fmts);
459 :
460 : /**
461 : * @atomic_check:
462 : *
463 : * This method is responsible for checking bridge state correctness.
464 : * It can also check the state of the surrounding components in chain
465 : * to make sure the whole pipeline can work properly.
466 : *
467 : * &drm_bridge_funcs.atomic_check() hooks are called in reverse
468 : * order (from the last to the first bridge).
469 : *
470 : * This method is optional. &drm_bridge_funcs.mode_fixup() is not
471 : * called when &drm_bridge_funcs.atomic_check() is implemented, so only
472 : * one of them should be provided.
473 : *
474 : * If drivers need to tweak &drm_bridge_state.input_bus_cfg.flags or
475 : * &drm_bridge_state.output_bus_cfg.flags it should happen in
476 : * this function. By default the &drm_bridge_state.output_bus_cfg.flags
477 : * field is set to the next bridge
478 : * &drm_bridge_state.input_bus_cfg.flags value or
479 : * &drm_connector.display_info.bus_flags if the bridge is the last
480 : * element in the chain.
481 : *
482 : * RETURNS:
483 : * zero if the check passed, a negative error code otherwise.
484 : */
485 : int (*atomic_check)(struct drm_bridge *bridge,
486 : struct drm_bridge_state *bridge_state,
487 : struct drm_crtc_state *crtc_state,
488 : struct drm_connector_state *conn_state);
489 :
490 : /**
491 : * @atomic_reset:
492 : *
493 : * Reset the bridge to a predefined state (or retrieve its current
494 : * state) and return a &drm_bridge_state object matching this state.
495 : * This function is called at attach time.
496 : *
497 : * The atomic_reset hook is mandatory if the bridge implements any of
498 : * the atomic hooks, and should be left unassigned otherwise. For
499 : * bridges that don't subclass &drm_bridge_state, the
500 : * drm_atomic_helper_bridge_reset() helper function shall be used to
501 : * implement this hook.
502 : *
503 : * Note that the atomic_reset() semantics is not exactly matching the
504 : * reset() semantics found on other components (connector, plane, ...).
505 : *
506 : * 1. The reset operation happens when the bridge is attached, not when
507 : * drm_mode_config_reset() is called
508 : * 2. It's meant to be used exclusively on bridges that have been
509 : * converted to the ATOMIC API
510 : *
511 : * RETURNS:
512 : * A valid drm_bridge_state object in case of success, an ERR_PTR()
513 : * giving the reason of the failure otherwise.
514 : */
515 : struct drm_bridge_state *(*atomic_reset)(struct drm_bridge *bridge);
516 :
517 : /**
518 : * @detect:
519 : *
520 : * Check if anything is attached to the bridge output.
521 : *
522 : * This callback is optional, if not implemented the bridge will be
523 : * considered as always having a component attached to its output.
524 : * Bridges that implement this callback shall set the
525 : * DRM_BRIDGE_OP_DETECT flag in their &drm_bridge->ops.
526 : *
527 : * RETURNS:
528 : *
529 : * drm_connector_status indicating the bridge output status.
530 : */
531 : enum drm_connector_status (*detect)(struct drm_bridge *bridge);
532 :
533 : /**
534 : * @get_modes:
535 : *
536 : * Fill all modes currently valid for the sink into the &drm_connector
537 : * with drm_mode_probed_add().
538 : *
539 : * The @get_modes callback is mostly intended to support non-probeable
540 : * displays such as many fixed panels. Bridges that support reading
541 : * EDID shall leave @get_modes unimplemented and implement the
542 : * &drm_bridge_funcs->get_edid callback instead.
543 : *
544 : * This callback is optional. Bridges that implement it shall set the
545 : * DRM_BRIDGE_OP_MODES flag in their &drm_bridge->ops.
546 : *
547 : * The connector parameter shall be used for the sole purpose of
548 : * filling modes, and shall not be stored internally by bridge drivers
549 : * for future usage.
550 : *
551 : * RETURNS:
552 : *
553 : * The number of modes added by calling drm_mode_probed_add().
554 : */
555 : int (*get_modes)(struct drm_bridge *bridge,
556 : struct drm_connector *connector);
557 :
558 : /**
559 : * @get_edid:
560 : *
561 : * Read and parse the EDID data of the connected display.
562 : *
563 : * The @get_edid callback is the preferred way of reporting mode
564 : * information for a display connected to the bridge output. Bridges
565 : * that support reading EDID shall implement this callback and leave
566 : * the @get_modes callback unimplemented.
567 : *
568 : * The caller of this operation shall first verify the output
569 : * connection status and refrain from reading EDID from a disconnected
570 : * output.
571 : *
572 : * This callback is optional. Bridges that implement it shall set the
573 : * DRM_BRIDGE_OP_EDID flag in their &drm_bridge->ops.
574 : *
575 : * The connector parameter shall be used for the sole purpose of EDID
576 : * retrieval and parsing, and shall not be stored internally by bridge
577 : * drivers for future usage.
578 : *
579 : * RETURNS:
580 : *
581 : * An edid structure newly allocated with kmalloc() (or similar) on
582 : * success, or NULL otherwise. The caller is responsible for freeing
583 : * the returned edid structure with kfree().
584 : */
585 : struct edid *(*get_edid)(struct drm_bridge *bridge,
586 : struct drm_connector *connector);
587 :
588 : /**
589 : * @hpd_notify:
590 : *
591 : * Notify the bridge of hot plug detection.
592 : *
593 : * This callback is optional, it may be implemented by bridges that
594 : * need to be notified of display connection or disconnection for
595 : * internal reasons. One use case is to reset the internal state of CEC
596 : * controllers for HDMI bridges.
597 : */
598 : void (*hpd_notify)(struct drm_bridge *bridge,
599 : enum drm_connector_status status);
600 :
601 : /**
602 : * @hpd_enable:
603 : *
604 : * Enable hot plug detection. From now on the bridge shall call
605 : * drm_bridge_hpd_notify() each time a change is detected in the output
606 : * connection status, until hot plug detection gets disabled with
607 : * @hpd_disable.
608 : *
609 : * This callback is optional and shall only be implemented by bridges
610 : * that support hot-plug notification without polling. Bridges that
611 : * implement it shall also implement the @hpd_disable callback and set
612 : * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops.
613 : */
614 : void (*hpd_enable)(struct drm_bridge *bridge);
615 :
616 : /**
617 : * @hpd_disable:
618 : *
619 : * Disable hot plug detection. Once this function returns the bridge
620 : * shall not call drm_bridge_hpd_notify() when a change in the output
621 : * connection status occurs.
622 : *
623 : * This callback is optional and shall only be implemented by bridges
624 : * that support hot-plug notification without polling. Bridges that
625 : * implement it shall also implement the @hpd_enable callback and set
626 : * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops.
627 : */
628 : void (*hpd_disable)(struct drm_bridge *bridge);
629 :
630 : /**
631 : * @debugfs_init:
632 : *
633 : * Allows bridges to create bridge-specific debugfs files.
634 : */
635 : void (*debugfs_init)(struct drm_bridge *bridge, struct dentry *root);
636 : };
637 :
638 : /**
639 : * struct drm_bridge_timings - timing information for the bridge
640 : */
641 : struct drm_bridge_timings {
642 : /**
643 : * @input_bus_flags:
644 : *
645 : * Tells what additional settings for the pixel data on the bus
646 : * this bridge requires (like pixel signal polarity). See also
647 : * &drm_display_info->bus_flags.
648 : */
649 : u32 input_bus_flags;
650 : /**
651 : * @setup_time_ps:
652 : *
653 : * Defines the time in picoseconds the input data lines must be
654 : * stable before the clock edge.
655 : */
656 : u32 setup_time_ps;
657 : /**
658 : * @hold_time_ps:
659 : *
660 : * Defines the time in picoseconds taken for the bridge to sample the
661 : * input signal after the clock edge.
662 : */
663 : u32 hold_time_ps;
664 : /**
665 : * @dual_link:
666 : *
667 : * True if the bus operates in dual-link mode. The exact meaning is
668 : * dependent on the bus type. For LVDS buses, this indicates that even-
669 : * and odd-numbered pixels are received on separate links.
670 : */
671 : bool dual_link;
672 : };
673 :
674 : /**
675 : * enum drm_bridge_ops - Bitmask of operations supported by the bridge
676 : */
677 : enum drm_bridge_ops {
678 : /**
679 : * @DRM_BRIDGE_OP_DETECT: The bridge can detect displays connected to
680 : * its output. Bridges that set this flag shall implement the
681 : * &drm_bridge_funcs->detect callback.
682 : */
683 : DRM_BRIDGE_OP_DETECT = BIT(0),
684 : /**
685 : * @DRM_BRIDGE_OP_EDID: The bridge can retrieve the EDID of the display
686 : * connected to its output. Bridges that set this flag shall implement
687 : * the &drm_bridge_funcs->get_edid callback.
688 : */
689 : DRM_BRIDGE_OP_EDID = BIT(1),
690 : /**
691 : * @DRM_BRIDGE_OP_HPD: The bridge can detect hot-plug and hot-unplug
692 : * without requiring polling. Bridges that set this flag shall
693 : * implement the &drm_bridge_funcs->hpd_enable and
694 : * &drm_bridge_funcs->hpd_disable callbacks if they support enabling
695 : * and disabling hot-plug detection dynamically.
696 : */
697 : DRM_BRIDGE_OP_HPD = BIT(2),
698 : /**
699 : * @DRM_BRIDGE_OP_MODES: The bridge can retrieve the modes supported
700 : * by the display at its output. This does not include reading EDID
701 : * which is separately covered by @DRM_BRIDGE_OP_EDID. Bridges that set
702 : * this flag shall implement the &drm_bridge_funcs->get_modes callback.
703 : */
704 : DRM_BRIDGE_OP_MODES = BIT(3),
705 : };
706 :
707 : /**
708 : * struct drm_bridge - central DRM bridge control structure
709 : */
710 : struct drm_bridge {
711 : /** @base: inherit from &drm_private_object */
712 : struct drm_private_obj base;
713 : /** @dev: DRM device this bridge belongs to */
714 : struct drm_device *dev;
715 : /** @encoder: encoder to which this bridge is connected */
716 : struct drm_encoder *encoder;
717 : /** @chain_node: used to form a bridge chain */
718 : struct list_head chain_node;
719 : #ifdef CONFIG_OF
720 : /** @of_node: device node pointer to the bridge */
721 : struct device_node *of_node;
722 : #endif
723 : /** @list: to keep track of all added bridges */
724 : struct list_head list;
725 : /**
726 : * @timings:
727 : *
728 : * the timing specification for the bridge, if any (may be NULL)
729 : */
730 : const struct drm_bridge_timings *timings;
731 : /** @funcs: control functions */
732 : const struct drm_bridge_funcs *funcs;
733 : /** @driver_private: pointer to the bridge driver's internal context */
734 : void *driver_private;
735 : /** @ops: bitmask of operations supported by the bridge */
736 : enum drm_bridge_ops ops;
737 : /**
738 : * @type: Type of the connection at the bridge output
739 : * (DRM_MODE_CONNECTOR_*). For bridges at the end of this chain this
740 : * identifies the type of connected display.
741 : */
742 : int type;
743 : /**
744 : * @interlace_allowed: Indicate that the bridge can handle interlaced
745 : * modes.
746 : */
747 : bool interlace_allowed;
748 : /**
749 : * @pre_enable_prev_first: The bridge requires that the prev
750 : * bridge @pre_enable function is called before its @pre_enable,
751 : * and conversely for post_disable. This is most frequently a
752 : * requirement for DSI devices which need the host to be initialised
753 : * before the peripheral.
754 : */
755 : bool pre_enable_prev_first;
756 : /**
757 : * @ddc: Associated I2C adapter for DDC access, if any.
758 : */
759 : struct i2c_adapter *ddc;
760 : /** private: */
761 : /**
762 : * @hpd_mutex: Protects the @hpd_cb and @hpd_data fields.
763 : */
764 : struct mutex hpd_mutex;
765 : /**
766 : * @hpd_cb: Hot plug detection callback, registered with
767 : * drm_bridge_hpd_enable().
768 : */
769 : void (*hpd_cb)(void *data, enum drm_connector_status status);
770 : /**
771 : * @hpd_data: Private data passed to the Hot plug detection callback
772 : * @hpd_cb.
773 : */
774 : void *hpd_data;
775 : };
776 :
777 : static inline struct drm_bridge *
778 : drm_priv_to_bridge(struct drm_private_obj *priv)
779 : {
780 0 : return container_of(priv, struct drm_bridge, base);
781 : }
782 :
783 : void drm_bridge_add(struct drm_bridge *bridge);
784 : int devm_drm_bridge_add(struct device *dev, struct drm_bridge *bridge);
785 : void drm_bridge_remove(struct drm_bridge *bridge);
786 : int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
787 : struct drm_bridge *previous,
788 : enum drm_bridge_attach_flags flags);
789 :
790 : #ifdef CONFIG_OF
791 : struct drm_bridge *of_drm_find_bridge(struct device_node *np);
792 : #else
793 : static inline struct drm_bridge *of_drm_find_bridge(struct device_node *np)
794 : {
795 : return NULL;
796 : }
797 : #endif
798 :
799 : /**
800 : * drm_bridge_get_next_bridge() - Get the next bridge in the chain
801 : * @bridge: bridge object
802 : *
803 : * RETURNS:
804 : * the next bridge in the chain after @bridge, or NULL if @bridge is the last.
805 : */
806 : static inline struct drm_bridge *
807 : drm_bridge_get_next_bridge(struct drm_bridge *bridge)
808 : {
809 0 : if (list_is_last(&bridge->chain_node, &bridge->encoder->bridge_chain))
810 : return NULL;
811 :
812 0 : return list_next_entry(bridge, chain_node);
813 : }
814 :
815 : /**
816 : * drm_bridge_get_prev_bridge() - Get the previous bridge in the chain
817 : * @bridge: bridge object
818 : *
819 : * RETURNS:
820 : * the previous bridge in the chain, or NULL if @bridge is the first.
821 : */
822 : static inline struct drm_bridge *
823 : drm_bridge_get_prev_bridge(struct drm_bridge *bridge)
824 : {
825 0 : if (list_is_first(&bridge->chain_node, &bridge->encoder->bridge_chain))
826 : return NULL;
827 :
828 0 : return list_prev_entry(bridge, chain_node);
829 : }
830 :
831 : /**
832 : * drm_bridge_chain_get_first_bridge() - Get the first bridge in the chain
833 : * @encoder: encoder object
834 : *
835 : * RETURNS:
836 : * the first bridge in the chain, or NULL if @encoder has no bridge attached
837 : * to it.
838 : */
839 : static inline struct drm_bridge *
840 : drm_bridge_chain_get_first_bridge(struct drm_encoder *encoder)
841 : {
842 0 : return list_first_entry_or_null(&encoder->bridge_chain,
843 : struct drm_bridge, chain_node);
844 : }
845 :
846 : /**
847 : * drm_for_each_bridge_in_chain() - Iterate over all bridges present in a chain
848 : * @encoder: the encoder to iterate bridges on
849 : * @bridge: a bridge pointer updated to point to the current bridge at each
850 : * iteration
851 : *
852 : * Iterate over all bridges present in the bridge chain attached to @encoder.
853 : */
854 : #define drm_for_each_bridge_in_chain(encoder, bridge) \
855 : list_for_each_entry(bridge, &(encoder)->bridge_chain, chain_node)
856 :
857 : bool drm_bridge_chain_mode_fixup(struct drm_bridge *bridge,
858 : const struct drm_display_mode *mode,
859 : struct drm_display_mode *adjusted_mode);
860 : enum drm_mode_status
861 : drm_bridge_chain_mode_valid(struct drm_bridge *bridge,
862 : const struct drm_display_info *info,
863 : const struct drm_display_mode *mode);
864 : void drm_bridge_chain_mode_set(struct drm_bridge *bridge,
865 : const struct drm_display_mode *mode,
866 : const struct drm_display_mode *adjusted_mode);
867 :
868 : int drm_atomic_bridge_chain_check(struct drm_bridge *bridge,
869 : struct drm_crtc_state *crtc_state,
870 : struct drm_connector_state *conn_state);
871 : void drm_atomic_bridge_chain_disable(struct drm_bridge *bridge,
872 : struct drm_atomic_state *state);
873 : void drm_atomic_bridge_chain_post_disable(struct drm_bridge *bridge,
874 : struct drm_atomic_state *state);
875 : void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge,
876 : struct drm_atomic_state *state);
877 : void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge,
878 : struct drm_atomic_state *state);
879 :
880 : u32 *
881 : drm_atomic_helper_bridge_propagate_bus_fmt(struct drm_bridge *bridge,
882 : struct drm_bridge_state *bridge_state,
883 : struct drm_crtc_state *crtc_state,
884 : struct drm_connector_state *conn_state,
885 : u32 output_fmt,
886 : unsigned int *num_input_fmts);
887 :
888 : enum drm_connector_status drm_bridge_detect(struct drm_bridge *bridge);
889 : int drm_bridge_get_modes(struct drm_bridge *bridge,
890 : struct drm_connector *connector);
891 : struct edid *drm_bridge_get_edid(struct drm_bridge *bridge,
892 : struct drm_connector *connector);
893 : void drm_bridge_hpd_enable(struct drm_bridge *bridge,
894 : void (*cb)(void *data,
895 : enum drm_connector_status status),
896 : void *data);
897 : void drm_bridge_hpd_disable(struct drm_bridge *bridge);
898 : void drm_bridge_hpd_notify(struct drm_bridge *bridge,
899 : enum drm_connector_status status);
900 :
901 : #ifdef CONFIG_DRM_PANEL_BRIDGE
902 : bool drm_bridge_is_panel(const struct drm_bridge *bridge);
903 : struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel);
904 : struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
905 : u32 connector_type);
906 : void drm_panel_bridge_remove(struct drm_bridge *bridge);
907 : int drm_panel_bridge_set_orientation(struct drm_connector *connector,
908 : struct drm_bridge *bridge);
909 : struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
910 : struct drm_panel *panel);
911 : struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev,
912 : struct drm_panel *panel,
913 : u32 connector_type);
914 : struct drm_bridge *drmm_panel_bridge_add(struct drm_device *drm,
915 : struct drm_panel *panel);
916 : struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge);
917 : #else
918 : static inline bool drm_bridge_is_panel(const struct drm_bridge *bridge)
919 : {
920 : return false;
921 : }
922 :
923 : static inline int drm_panel_bridge_set_orientation(struct drm_connector *connector,
924 : struct drm_bridge *bridge)
925 : {
926 : return -EINVAL;
927 : }
928 : #endif
929 :
930 : #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL_BRIDGE)
931 : struct drm_bridge *devm_drm_of_get_bridge(struct device *dev, struct device_node *node,
932 : u32 port, u32 endpoint);
933 : struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm, struct device_node *node,
934 : u32 port, u32 endpoint);
935 : #else
936 : static inline struct drm_bridge *devm_drm_of_get_bridge(struct device *dev,
937 : struct device_node *node,
938 : u32 port,
939 : u32 endpoint)
940 : {
941 : return ERR_PTR(-ENODEV);
942 : }
943 :
944 : static inline struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm,
945 : struct device_node *node,
946 : u32 port,
947 : u32 endpoint)
948 : {
949 : return ERR_PTR(-ENODEV);
950 : }
951 : #endif
952 :
953 : void drm_bridge_debugfs_init(struct drm_minor *minor);
954 :
955 : #endif
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