Line data Source code
1 : /*
2 : * Copyright © 2006 Keith Packard
3 : * Copyright © 2007-2008 Dave Airlie
4 : * Copyright © 2007-2008 Intel Corporation
5 : * Jesse Barnes <jesse.barnes@intel.com>
6 : * Copyright © 2011-2013 Intel Corporation
7 : * Copyright © 2015 Intel Corporation
8 : * Daniel Vetter <daniel.vetter@ffwll.ch>
9 : *
10 : * Permission is hereby granted, free of charge, to any person obtaining a
11 : * copy of this software and associated documentation files (the "Software"),
12 : * to deal in the Software without restriction, including without limitation
13 : * the rights to use, copy, modify, merge, publish, distribute, sublicense,
14 : * and/or sell copies of the Software, and to permit persons to whom the
15 : * Software is furnished to do so, subject to the following conditions:
16 : *
17 : * The above copyright notice and this permission notice shall be included in
18 : * all copies or substantial portions of the Software.
19 : *
20 : * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 : * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 : * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23 : * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
24 : * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
25 : * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
26 : * OTHER DEALINGS IN THE SOFTWARE.
27 : */
28 :
29 : #ifndef __DRM_MODESET_HELPER_VTABLES_H__
30 : #define __DRM_MODESET_HELPER_VTABLES_H__
31 :
32 : #include <drm/drm_crtc.h>
33 : #include <drm/drm_encoder.h>
34 :
35 : /**
36 : * DOC: overview
37 : *
38 : * The DRM mode setting helper functions are common code for drivers to use if
39 : * they wish. Drivers are not forced to use this code in their
40 : * implementations but it would be useful if the code they do use at least
41 : * provides a consistent interface and operation to userspace. Therefore it is
42 : * highly recommended to use the provided helpers as much as possible.
43 : *
44 : * Because there is only one pointer per modeset object to hold a vfunc table
45 : * for helper libraries they are by necessity shared among the different
46 : * helpers.
47 : *
48 : * To make this clear all the helper vtables are pulled together in this location here.
49 : */
50 :
51 : struct drm_writeback_connector;
52 : struct drm_writeback_job;
53 :
54 : enum mode_set_atomic {
55 : LEAVE_ATOMIC_MODE_SET,
56 : ENTER_ATOMIC_MODE_SET,
57 : };
58 :
59 : /**
60 : * struct drm_crtc_helper_funcs - helper operations for CRTCs
61 : *
62 : * These hooks are used by the legacy CRTC helpers and the new atomic
63 : * modesetting helpers.
64 : */
65 : struct drm_crtc_helper_funcs {
66 : /**
67 : * @dpms:
68 : *
69 : * Callback to control power levels on the CRTC. If the mode passed in
70 : * is unsupported, the provider must use the next lowest power level.
71 : * This is used by the legacy CRTC helpers to implement DPMS
72 : * functionality in drm_helper_connector_dpms().
73 : *
74 : * This callback is also used to disable a CRTC by calling it with
75 : * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
76 : *
77 : * This callback is used by the legacy CRTC helpers. Atomic helpers
78 : * also support using this hook for enabling and disabling a CRTC to
79 : * facilitate transitions to atomic, but it is deprecated. Instead
80 : * @atomic_enable and @atomic_disable should be used.
81 : */
82 : void (*dpms)(struct drm_crtc *crtc, int mode);
83 :
84 : /**
85 : * @prepare:
86 : *
87 : * This callback should prepare the CRTC for a subsequent modeset, which
88 : * in practice means the driver should disable the CRTC if it is
89 : * running. Most drivers ended up implementing this by calling their
90 : * @dpms hook with DRM_MODE_DPMS_OFF.
91 : *
92 : * This callback is used by the legacy CRTC helpers. Atomic helpers
93 : * also support using this hook for disabling a CRTC to facilitate
94 : * transitions to atomic, but it is deprecated. Instead @atomic_disable
95 : * should be used.
96 : */
97 : void (*prepare)(struct drm_crtc *crtc);
98 :
99 : /**
100 : * @commit:
101 : *
102 : * This callback should commit the new mode on the CRTC after a modeset,
103 : * which in practice means the driver should enable the CRTC. Most
104 : * drivers ended up implementing this by calling their @dpms hook with
105 : * DRM_MODE_DPMS_ON.
106 : *
107 : * This callback is used by the legacy CRTC helpers. Atomic helpers
108 : * also support using this hook for enabling a CRTC to facilitate
109 : * transitions to atomic, but it is deprecated. Instead @atomic_enable
110 : * should be used.
111 : */
112 : void (*commit)(struct drm_crtc *crtc);
113 :
114 : /**
115 : * @mode_valid:
116 : *
117 : * This callback is used to check if a specific mode is valid in this
118 : * crtc. This should be implemented if the crtc has some sort of
119 : * restriction in the modes it can display. For example, a given crtc
120 : * may be responsible to set a clock value. If the clock can not
121 : * produce all the values for the available modes then this callback
122 : * can be used to restrict the number of modes to only the ones that
123 : * can be displayed.
124 : *
125 : * This hook is used by the probe helpers to filter the mode list in
126 : * drm_helper_probe_single_connector_modes(), and it is used by the
127 : * atomic helpers to validate modes supplied by userspace in
128 : * drm_atomic_helper_check_modeset().
129 : *
130 : * This function is optional.
131 : *
132 : * NOTE:
133 : *
134 : * Since this function is both called from the check phase of an atomic
135 : * commit, and the mode validation in the probe paths it is not allowed
136 : * to look at anything else but the passed-in mode, and validate it
137 : * against configuration-invariant hardward constraints. Any further
138 : * limits which depend upon the configuration can only be checked in
139 : * @mode_fixup or @atomic_check.
140 : *
141 : * RETURNS:
142 : *
143 : * drm_mode_status Enum
144 : */
145 : enum drm_mode_status (*mode_valid)(struct drm_crtc *crtc,
146 : const struct drm_display_mode *mode);
147 :
148 : /**
149 : * @mode_fixup:
150 : *
151 : * This callback is used to validate a mode. The parameter mode is the
152 : * display mode that userspace requested, adjusted_mode is the mode the
153 : * encoders need to be fed with. Note that this is the inverse semantics
154 : * of the meaning for the &drm_encoder and &drm_bridge_funcs.mode_fixup
155 : * vfunc. If the CRTC cannot support the requested conversion from mode
156 : * to adjusted_mode it should reject the modeset. See also
157 : * &drm_crtc_state.adjusted_mode for more details.
158 : *
159 : * This function is used by both legacy CRTC helpers and atomic helpers.
160 : * With atomic helpers it is optional.
161 : *
162 : * NOTE:
163 : *
164 : * This function is called in the check phase of atomic modesets, which
165 : * can be aborted for any reason (including on userspace's request to
166 : * just check whether a configuration would be possible). Atomic drivers
167 : * MUST NOT touch any persistent state (hardware or software) or data
168 : * structures except the passed in adjusted_mode parameter.
169 : *
170 : * This is in contrast to the legacy CRTC helpers where this was
171 : * allowed.
172 : *
173 : * Atomic drivers which need to inspect and adjust more state should
174 : * instead use the @atomic_check callback, but note that they're not
175 : * perfectly equivalent: @mode_valid is called from
176 : * drm_atomic_helper_check_modeset(), but @atomic_check is called from
177 : * drm_atomic_helper_check_planes(), because originally it was meant for
178 : * plane update checks only.
179 : *
180 : * Also beware that userspace can request its own custom modes, neither
181 : * core nor helpers filter modes to the list of probe modes reported by
182 : * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
183 : * that modes are filtered consistently put any CRTC constraints and
184 : * limits checks into @mode_valid.
185 : *
186 : * RETURNS:
187 : *
188 : * True if an acceptable configuration is possible, false if the modeset
189 : * operation should be rejected.
190 : */
191 : bool (*mode_fixup)(struct drm_crtc *crtc,
192 : const struct drm_display_mode *mode,
193 : struct drm_display_mode *adjusted_mode);
194 :
195 : /**
196 : * @mode_set:
197 : *
198 : * This callback is used by the legacy CRTC helpers to set a new mode,
199 : * position and framebuffer. Since it ties the primary plane to every
200 : * mode change it is incompatible with universal plane support. And
201 : * since it can't update other planes it's incompatible with atomic
202 : * modeset support.
203 : *
204 : * This callback is only used by CRTC helpers and deprecated.
205 : *
206 : * RETURNS:
207 : *
208 : * 0 on success or a negative error code on failure.
209 : */
210 : int (*mode_set)(struct drm_crtc *crtc, struct drm_display_mode *mode,
211 : struct drm_display_mode *adjusted_mode, int x, int y,
212 : struct drm_framebuffer *old_fb);
213 :
214 : /**
215 : * @mode_set_nofb:
216 : *
217 : * This callback is used to update the display mode of a CRTC without
218 : * changing anything of the primary plane configuration. This fits the
219 : * requirement of atomic and hence is used by the atomic helpers.
220 : *
221 : * Note that the display pipe is completely off when this function is
222 : * called. Atomic drivers which need hardware to be running before they
223 : * program the new display mode (e.g. because they implement runtime PM)
224 : * should not use this hook. This is because the helper library calls
225 : * this hook only once per mode change and not every time the display
226 : * pipeline is suspended using either DPMS or the new "ACTIVE" property.
227 : * Which means register values set in this callback might get reset when
228 : * the CRTC is suspended, but not restored. Such drivers should instead
229 : * move all their CRTC setup into the @atomic_enable callback.
230 : *
231 : * This callback is optional.
232 : */
233 : void (*mode_set_nofb)(struct drm_crtc *crtc);
234 :
235 : /**
236 : * @mode_set_base:
237 : *
238 : * This callback is used by the legacy CRTC helpers to set a new
239 : * framebuffer and scanout position. It is optional and used as an
240 : * optimized fast-path instead of a full mode set operation with all the
241 : * resulting flickering. If it is not present
242 : * drm_crtc_helper_set_config() will fall back to a full modeset, using
243 : * the @mode_set callback. Since it can't update other planes it's
244 : * incompatible with atomic modeset support.
245 : *
246 : * This callback is only used by the CRTC helpers and deprecated.
247 : *
248 : * RETURNS:
249 : *
250 : * 0 on success or a negative error code on failure.
251 : */
252 : int (*mode_set_base)(struct drm_crtc *crtc, int x, int y,
253 : struct drm_framebuffer *old_fb);
254 :
255 : /**
256 : * @mode_set_base_atomic:
257 : *
258 : * This callback is used by the fbdev helpers to set a new framebuffer
259 : * and scanout without sleeping, i.e. from an atomic calling context. It
260 : * is only used to implement kgdb support.
261 : *
262 : * This callback is optional and only needed for kgdb support in the fbdev
263 : * helpers.
264 : *
265 : * RETURNS:
266 : *
267 : * 0 on success or a negative error code on failure.
268 : */
269 : int (*mode_set_base_atomic)(struct drm_crtc *crtc,
270 : struct drm_framebuffer *fb, int x, int y,
271 : enum mode_set_atomic);
272 :
273 : /**
274 : * @disable:
275 : *
276 : * This callback should be used to disable the CRTC. With the atomic
277 : * drivers it is called after all encoders connected to this CRTC have
278 : * been shut off already using their own
279 : * &drm_encoder_helper_funcs.disable hook. If that sequence is too
280 : * simple drivers can just add their own hooks and call it from this
281 : * CRTC callback here by looping over all encoders connected to it using
282 : * for_each_encoder_on_crtc().
283 : *
284 : * This hook is used both by legacy CRTC helpers and atomic helpers.
285 : * Atomic drivers don't need to implement it if there's no need to
286 : * disable anything at the CRTC level. To ensure that runtime PM
287 : * handling (using either DPMS or the new "ACTIVE" property) works
288 : * @disable must be the inverse of @atomic_enable for atomic drivers.
289 : * Atomic drivers should consider to use @atomic_disable instead of
290 : * this one.
291 : *
292 : * NOTE:
293 : *
294 : * With legacy CRTC helpers there's a big semantic difference between
295 : * @disable and other hooks (like @prepare or @dpms) used to shut down a
296 : * CRTC: @disable is only called when also logically disabling the
297 : * display pipeline and needs to release any resources acquired in
298 : * @mode_set (like shared PLLs, or again release pinned framebuffers).
299 : *
300 : * Therefore @disable must be the inverse of @mode_set plus @commit for
301 : * drivers still using legacy CRTC helpers, which is different from the
302 : * rules under atomic.
303 : */
304 : void (*disable)(struct drm_crtc *crtc);
305 :
306 : /**
307 : * @atomic_check:
308 : *
309 : * Drivers should check plane-update related CRTC constraints in this
310 : * hook. They can also check mode related limitations but need to be
311 : * aware of the calling order, since this hook is used by
312 : * drm_atomic_helper_check_planes() whereas the preparations needed to
313 : * check output routing and the display mode is done in
314 : * drm_atomic_helper_check_modeset(). Therefore drivers that want to
315 : * check output routing and display mode constraints in this callback
316 : * must ensure that drm_atomic_helper_check_modeset() has been called
317 : * beforehand. This is calling order used by the default helper
318 : * implementation in drm_atomic_helper_check().
319 : *
320 : * When using drm_atomic_helper_check_planes() this hook is called
321 : * after the &drm_plane_helper_funcs.atomic_check hook for planes, which
322 : * allows drivers to assign shared resources requested by planes in this
323 : * callback here. For more complicated dependencies the driver can call
324 : * the provided check helpers multiple times until the computed state
325 : * has a final configuration and everything has been checked.
326 : *
327 : * This function is also allowed to inspect any other object's state and
328 : * can add more state objects to the atomic commit if needed. Care must
329 : * be taken though to ensure that state check and compute functions for
330 : * these added states are all called, and derived state in other objects
331 : * all updated. Again the recommendation is to just call check helpers
332 : * until a maximal configuration is reached.
333 : *
334 : * This callback is used by the atomic modeset helpers, but it is
335 : * optional.
336 : *
337 : * NOTE:
338 : *
339 : * This function is called in the check phase of an atomic update. The
340 : * driver is not allowed to change anything outside of the free-standing
341 : * state object passed-in.
342 : *
343 : * Also beware that userspace can request its own custom modes, neither
344 : * core nor helpers filter modes to the list of probe modes reported by
345 : * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
346 : * that modes are filtered consistently put any CRTC constraints and
347 : * limits checks into @mode_valid.
348 : *
349 : * RETURNS:
350 : *
351 : * 0 on success, -EINVAL if the state or the transition can't be
352 : * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
353 : * attempt to obtain another state object ran into a &drm_modeset_lock
354 : * deadlock.
355 : */
356 : int (*atomic_check)(struct drm_crtc *crtc,
357 : struct drm_atomic_state *state);
358 :
359 : /**
360 : * @atomic_begin:
361 : *
362 : * Drivers should prepare for an atomic update of multiple planes on
363 : * a CRTC in this hook. Depending upon hardware this might be vblank
364 : * evasion, blocking updates by setting bits or doing preparatory work
365 : * for e.g. manual update display.
366 : *
367 : * This hook is called before any plane commit functions are called.
368 : *
369 : * Note that the power state of the display pipe when this function is
370 : * called depends upon the exact helpers and calling sequence the driver
371 : * has picked. See drm_atomic_helper_commit_planes() for a discussion of
372 : * the tradeoffs and variants of plane commit helpers.
373 : *
374 : * This callback is used by the atomic modeset helpers, but it is
375 : * optional.
376 : */
377 : void (*atomic_begin)(struct drm_crtc *crtc,
378 : struct drm_atomic_state *state);
379 : /**
380 : * @atomic_flush:
381 : *
382 : * Drivers should finalize an atomic update of multiple planes on
383 : * a CRTC in this hook. Depending upon hardware this might include
384 : * checking that vblank evasion was successful, unblocking updates by
385 : * setting bits or setting the GO bit to flush out all updates.
386 : *
387 : * Simple hardware or hardware with special requirements can commit and
388 : * flush out all updates for all planes from this hook and forgo all the
389 : * other commit hooks for plane updates.
390 : *
391 : * This hook is called after any plane commit functions are called.
392 : *
393 : * Note that the power state of the display pipe when this function is
394 : * called depends upon the exact helpers and calling sequence the driver
395 : * has picked. See drm_atomic_helper_commit_planes() for a discussion of
396 : * the tradeoffs and variants of plane commit helpers.
397 : *
398 : * This callback is used by the atomic modeset helpers, but it is
399 : * optional.
400 : */
401 : void (*atomic_flush)(struct drm_crtc *crtc,
402 : struct drm_atomic_state *state);
403 :
404 : /**
405 : * @atomic_enable:
406 : *
407 : * This callback should be used to enable the CRTC. With the atomic
408 : * drivers it is called before all encoders connected to this CRTC are
409 : * enabled through the encoder's own &drm_encoder_helper_funcs.enable
410 : * hook. If that sequence is too simple drivers can just add their own
411 : * hooks and call it from this CRTC callback here by looping over all
412 : * encoders connected to it using for_each_encoder_on_crtc().
413 : *
414 : * This hook is used only by atomic helpers, for symmetry with
415 : * @atomic_disable. Atomic drivers don't need to implement it if there's
416 : * no need to enable anything at the CRTC level. To ensure that runtime
417 : * PM handling (using either DPMS or the new "ACTIVE" property) works
418 : * @atomic_enable must be the inverse of @atomic_disable for atomic
419 : * drivers.
420 : *
421 : * This function is optional.
422 : */
423 : void (*atomic_enable)(struct drm_crtc *crtc,
424 : struct drm_atomic_state *state);
425 :
426 : /**
427 : * @atomic_disable:
428 : *
429 : * This callback should be used to disable the CRTC. With the atomic
430 : * drivers it is called after all encoders connected to this CRTC have
431 : * been shut off already using their own
432 : * &drm_encoder_helper_funcs.disable hook. If that sequence is too
433 : * simple drivers can just add their own hooks and call it from this
434 : * CRTC callback here by looping over all encoders connected to it using
435 : * for_each_encoder_on_crtc().
436 : *
437 : * This hook is used only by atomic helpers. Atomic drivers don't
438 : * need to implement it if there's no need to disable anything at the
439 : * CRTC level.
440 : *
441 : * This function is optional.
442 : */
443 : void (*atomic_disable)(struct drm_crtc *crtc,
444 : struct drm_atomic_state *state);
445 :
446 : /**
447 : * @get_scanout_position:
448 : *
449 : * Called by vblank timestamping code.
450 : *
451 : * Returns the current display scanout position from a CRTC and an
452 : * optional accurate ktime_get() timestamp of when the position was
453 : * measured. Note that this is a helper callback which is only used
454 : * if a driver uses drm_crtc_vblank_helper_get_vblank_timestamp()
455 : * for the @drm_crtc_funcs.get_vblank_timestamp callback.
456 : *
457 : * Parameters:
458 : *
459 : * crtc:
460 : * The CRTC.
461 : * in_vblank_irq:
462 : * True when called from drm_crtc_handle_vblank(). Some drivers
463 : * need to apply some workarounds for gpu-specific vblank irq
464 : * quirks if the flag is set.
465 : * vpos:
466 : * Target location for current vertical scanout position.
467 : * hpos:
468 : * Target location for current horizontal scanout position.
469 : * stime:
470 : * Target location for timestamp taken immediately before
471 : * scanout position query. Can be NULL to skip timestamp.
472 : * etime:
473 : * Target location for timestamp taken immediately after
474 : * scanout position query. Can be NULL to skip timestamp.
475 : * mode:
476 : * Current display timings.
477 : *
478 : * Returns vpos as a positive number while in active scanout area.
479 : * Returns vpos as a negative number inside vblank, counting the number
480 : * of scanlines to go until end of vblank, e.g., -1 means "one scanline
481 : * until start of active scanout / end of vblank."
482 : *
483 : * Returns:
484 : *
485 : * True on success, false if a reliable scanout position counter could
486 : * not be read out.
487 : */
488 : bool (*get_scanout_position)(struct drm_crtc *crtc,
489 : bool in_vblank_irq, int *vpos, int *hpos,
490 : ktime_t *stime, ktime_t *etime,
491 : const struct drm_display_mode *mode);
492 : };
493 :
494 : /**
495 : * drm_crtc_helper_add - sets the helper vtable for a crtc
496 : * @crtc: DRM CRTC
497 : * @funcs: helper vtable to set for @crtc
498 : */
499 : static inline void drm_crtc_helper_add(struct drm_crtc *crtc,
500 : const struct drm_crtc_helper_funcs *funcs)
501 : {
502 0 : crtc->helper_private = funcs;
503 : }
504 :
505 : /**
506 : * struct drm_encoder_helper_funcs - helper operations for encoders
507 : *
508 : * These hooks are used by the legacy CRTC helpers and the new atomic
509 : * modesetting helpers.
510 : */
511 : struct drm_encoder_helper_funcs {
512 : /**
513 : * @dpms:
514 : *
515 : * Callback to control power levels on the encoder. If the mode passed in
516 : * is unsupported, the provider must use the next lowest power level.
517 : * This is used by the legacy encoder helpers to implement DPMS
518 : * functionality in drm_helper_connector_dpms().
519 : *
520 : * This callback is also used to disable an encoder by calling it with
521 : * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
522 : *
523 : * This callback is used by the legacy CRTC helpers. Atomic helpers
524 : * also support using this hook for enabling and disabling an encoder to
525 : * facilitate transitions to atomic, but it is deprecated. Instead
526 : * @enable and @disable should be used.
527 : */
528 : void (*dpms)(struct drm_encoder *encoder, int mode);
529 :
530 : /**
531 : * @mode_valid:
532 : *
533 : * This callback is used to check if a specific mode is valid in this
534 : * encoder. This should be implemented if the encoder has some sort
535 : * of restriction in the modes it can display. For example, a given
536 : * encoder may be responsible to set a clock value. If the clock can
537 : * not produce all the values for the available modes then this callback
538 : * can be used to restrict the number of modes to only the ones that
539 : * can be displayed.
540 : *
541 : * This hook is used by the probe helpers to filter the mode list in
542 : * drm_helper_probe_single_connector_modes(), and it is used by the
543 : * atomic helpers to validate modes supplied by userspace in
544 : * drm_atomic_helper_check_modeset().
545 : *
546 : * This function is optional.
547 : *
548 : * NOTE:
549 : *
550 : * Since this function is both called from the check phase of an atomic
551 : * commit, and the mode validation in the probe paths it is not allowed
552 : * to look at anything else but the passed-in mode, and validate it
553 : * against configuration-invariant hardward constraints. Any further
554 : * limits which depend upon the configuration can only be checked in
555 : * @mode_fixup or @atomic_check.
556 : *
557 : * RETURNS:
558 : *
559 : * drm_mode_status Enum
560 : */
561 : enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc,
562 : const struct drm_display_mode *mode);
563 :
564 : /**
565 : * @mode_fixup:
566 : *
567 : * This callback is used to validate and adjust a mode. The parameter
568 : * mode is the display mode that should be fed to the next element in
569 : * the display chain, either the final &drm_connector or a &drm_bridge.
570 : * The parameter adjusted_mode is the input mode the encoder requires. It
571 : * can be modified by this callback and does not need to match mode. See
572 : * also &drm_crtc_state.adjusted_mode for more details.
573 : *
574 : * This function is used by both legacy CRTC helpers and atomic helpers.
575 : * This hook is optional.
576 : *
577 : * NOTE:
578 : *
579 : * This function is called in the check phase of atomic modesets, which
580 : * can be aborted for any reason (including on userspace's request to
581 : * just check whether a configuration would be possible). Atomic drivers
582 : * MUST NOT touch any persistent state (hardware or software) or data
583 : * structures except the passed in adjusted_mode parameter.
584 : *
585 : * This is in contrast to the legacy CRTC helpers where this was
586 : * allowed.
587 : *
588 : * Atomic drivers which need to inspect and adjust more state should
589 : * instead use the @atomic_check callback. If @atomic_check is used,
590 : * this hook isn't called since @atomic_check allows a strict superset
591 : * of the functionality of @mode_fixup.
592 : *
593 : * Also beware that userspace can request its own custom modes, neither
594 : * core nor helpers filter modes to the list of probe modes reported by
595 : * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
596 : * that modes are filtered consistently put any encoder constraints and
597 : * limits checks into @mode_valid.
598 : *
599 : * RETURNS:
600 : *
601 : * True if an acceptable configuration is possible, false if the modeset
602 : * operation should be rejected.
603 : */
604 : bool (*mode_fixup)(struct drm_encoder *encoder,
605 : const struct drm_display_mode *mode,
606 : struct drm_display_mode *adjusted_mode);
607 :
608 : /**
609 : * @prepare:
610 : *
611 : * This callback should prepare the encoder for a subsequent modeset,
612 : * which in practice means the driver should disable the encoder if it
613 : * is running. Most drivers ended up implementing this by calling their
614 : * @dpms hook with DRM_MODE_DPMS_OFF.
615 : *
616 : * This callback is used by the legacy CRTC helpers. Atomic helpers
617 : * also support using this hook for disabling an encoder to facilitate
618 : * transitions to atomic, but it is deprecated. Instead @disable should
619 : * be used.
620 : */
621 : void (*prepare)(struct drm_encoder *encoder);
622 :
623 : /**
624 : * @commit:
625 : *
626 : * This callback should commit the new mode on the encoder after a modeset,
627 : * which in practice means the driver should enable the encoder. Most
628 : * drivers ended up implementing this by calling their @dpms hook with
629 : * DRM_MODE_DPMS_ON.
630 : *
631 : * This callback is used by the legacy CRTC helpers. Atomic helpers
632 : * also support using this hook for enabling an encoder to facilitate
633 : * transitions to atomic, but it is deprecated. Instead @enable should
634 : * be used.
635 : */
636 : void (*commit)(struct drm_encoder *encoder);
637 :
638 : /**
639 : * @mode_set:
640 : *
641 : * This callback is used to update the display mode of an encoder.
642 : *
643 : * Note that the display pipe is completely off when this function is
644 : * called. Drivers which need hardware to be running before they program
645 : * the new display mode (because they implement runtime PM) should not
646 : * use this hook, because the helper library calls it only once and not
647 : * every time the display pipeline is suspend using either DPMS or the
648 : * new "ACTIVE" property. Such drivers should instead move all their
649 : * encoder setup into the @enable callback.
650 : *
651 : * This callback is used both by the legacy CRTC helpers and the atomic
652 : * modeset helpers. It is optional in the atomic helpers.
653 : *
654 : * NOTE:
655 : *
656 : * If the driver uses the atomic modeset helpers and needs to inspect
657 : * the connector state or connector display info during mode setting,
658 : * @atomic_mode_set can be used instead.
659 : */
660 : void (*mode_set)(struct drm_encoder *encoder,
661 : struct drm_display_mode *mode,
662 : struct drm_display_mode *adjusted_mode);
663 :
664 : /**
665 : * @atomic_mode_set:
666 : *
667 : * This callback is used to update the display mode of an encoder.
668 : *
669 : * Note that the display pipe is completely off when this function is
670 : * called. Drivers which need hardware to be running before they program
671 : * the new display mode (because they implement runtime PM) should not
672 : * use this hook, because the helper library calls it only once and not
673 : * every time the display pipeline is suspended using either DPMS or the
674 : * new "ACTIVE" property. Such drivers should instead move all their
675 : * encoder setup into the @enable callback.
676 : *
677 : * This callback is used by the atomic modeset helpers in place of the
678 : * @mode_set callback, if set by the driver. It is optional and should
679 : * be used instead of @mode_set if the driver needs to inspect the
680 : * connector state or display info, since there is no direct way to
681 : * go from the encoder to the current connector.
682 : */
683 : void (*atomic_mode_set)(struct drm_encoder *encoder,
684 : struct drm_crtc_state *crtc_state,
685 : struct drm_connector_state *conn_state);
686 :
687 : /**
688 : * @detect:
689 : *
690 : * This callback can be used by drivers who want to do detection on the
691 : * encoder object instead of in connector functions.
692 : *
693 : * It is not used by any helper and therefore has purely driver-specific
694 : * semantics. New drivers shouldn't use this and instead just implement
695 : * their own private callbacks.
696 : *
697 : * FIXME:
698 : *
699 : * This should just be converted into a pile of driver vfuncs.
700 : * Currently radeon, amdgpu and nouveau are using it.
701 : */
702 : enum drm_connector_status (*detect)(struct drm_encoder *encoder,
703 : struct drm_connector *connector);
704 :
705 : /**
706 : * @atomic_disable:
707 : *
708 : * This callback should be used to disable the encoder. With the atomic
709 : * drivers it is called before this encoder's CRTC has been shut off
710 : * using their own &drm_crtc_helper_funcs.atomic_disable hook. If that
711 : * sequence is too simple drivers can just add their own driver private
712 : * encoder hooks and call them from CRTC's callback by looping over all
713 : * encoders connected to it using for_each_encoder_on_crtc().
714 : *
715 : * This callback is a variant of @disable that provides the atomic state
716 : * to the driver. If @atomic_disable is implemented, @disable is not
717 : * called by the helpers.
718 : *
719 : * This hook is only used by atomic helpers. Atomic drivers don't need
720 : * to implement it if there's no need to disable anything at the encoder
721 : * level. To ensure that runtime PM handling (using either DPMS or the
722 : * new "ACTIVE" property) works @atomic_disable must be the inverse of
723 : * @atomic_enable.
724 : */
725 : void (*atomic_disable)(struct drm_encoder *encoder,
726 : struct drm_atomic_state *state);
727 :
728 : /**
729 : * @atomic_enable:
730 : *
731 : * This callback should be used to enable the encoder. It is called
732 : * after this encoder's CRTC has been enabled using their own
733 : * &drm_crtc_helper_funcs.atomic_enable hook. If that sequence is
734 : * too simple drivers can just add their own driver private encoder
735 : * hooks and call them from CRTC's callback by looping over all encoders
736 : * connected to it using for_each_encoder_on_crtc().
737 : *
738 : * This callback is a variant of @enable that provides the atomic state
739 : * to the driver. If @atomic_enable is implemented, @enable is not
740 : * called by the helpers.
741 : *
742 : * This hook is only used by atomic helpers, it is the opposite of
743 : * @atomic_disable. Atomic drivers don't need to implement it if there's
744 : * no need to enable anything at the encoder level. To ensure that
745 : * runtime PM handling works @atomic_enable must be the inverse of
746 : * @atomic_disable.
747 : */
748 : void (*atomic_enable)(struct drm_encoder *encoder,
749 : struct drm_atomic_state *state);
750 :
751 : /**
752 : * @disable:
753 : *
754 : * This callback should be used to disable the encoder. With the atomic
755 : * drivers it is called before this encoder's CRTC has been shut off
756 : * using their own &drm_crtc_helper_funcs.disable hook. If that
757 : * sequence is too simple drivers can just add their own driver private
758 : * encoder hooks and call them from CRTC's callback by looping over all
759 : * encoders connected to it using for_each_encoder_on_crtc().
760 : *
761 : * This hook is used both by legacy CRTC helpers and atomic helpers.
762 : * Atomic drivers don't need to implement it if there's no need to
763 : * disable anything at the encoder level. To ensure that runtime PM
764 : * handling (using either DPMS or the new "ACTIVE" property) works
765 : * @disable must be the inverse of @enable for atomic drivers.
766 : *
767 : * For atomic drivers also consider @atomic_disable and save yourself
768 : * from having to read the NOTE below!
769 : *
770 : * NOTE:
771 : *
772 : * With legacy CRTC helpers there's a big semantic difference between
773 : * @disable and other hooks (like @prepare or @dpms) used to shut down a
774 : * encoder: @disable is only called when also logically disabling the
775 : * display pipeline and needs to release any resources acquired in
776 : * @mode_set (like shared PLLs, or again release pinned framebuffers).
777 : *
778 : * Therefore @disable must be the inverse of @mode_set plus @commit for
779 : * drivers still using legacy CRTC helpers, which is different from the
780 : * rules under atomic.
781 : */
782 : void (*disable)(struct drm_encoder *encoder);
783 :
784 : /**
785 : * @enable:
786 : *
787 : * This callback should be used to enable the encoder. With the atomic
788 : * drivers it is called after this encoder's CRTC has been enabled using
789 : * their own &drm_crtc_helper_funcs.enable hook. If that sequence is
790 : * too simple drivers can just add their own driver private encoder
791 : * hooks and call them from CRTC's callback by looping over all encoders
792 : * connected to it using for_each_encoder_on_crtc().
793 : *
794 : * This hook is only used by atomic helpers, it is the opposite of
795 : * @disable. Atomic drivers don't need to implement it if there's no
796 : * need to enable anything at the encoder level. To ensure that
797 : * runtime PM handling (using either DPMS or the new "ACTIVE" property)
798 : * works @enable must be the inverse of @disable for atomic drivers.
799 : */
800 : void (*enable)(struct drm_encoder *encoder);
801 :
802 : /**
803 : * @atomic_check:
804 : *
805 : * This callback is used to validate encoder state for atomic drivers.
806 : * Since the encoder is the object connecting the CRTC and connector it
807 : * gets passed both states, to be able to validate interactions and
808 : * update the CRTC to match what the encoder needs for the requested
809 : * connector.
810 : *
811 : * Since this provides a strict superset of the functionality of
812 : * @mode_fixup (the requested and adjusted modes are both available
813 : * through the passed in &struct drm_crtc_state) @mode_fixup is not
814 : * called when @atomic_check is implemented.
815 : *
816 : * This function is used by the atomic helpers, but it is optional.
817 : *
818 : * NOTE:
819 : *
820 : * This function is called in the check phase of an atomic update. The
821 : * driver is not allowed to change anything outside of the free-standing
822 : * state objects passed-in or assembled in the overall &drm_atomic_state
823 : * update tracking structure.
824 : *
825 : * Also beware that userspace can request its own custom modes, neither
826 : * core nor helpers filter modes to the list of probe modes reported by
827 : * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
828 : * that modes are filtered consistently put any encoder constraints and
829 : * limits checks into @mode_valid.
830 : *
831 : * RETURNS:
832 : *
833 : * 0 on success, -EINVAL if the state or the transition can't be
834 : * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
835 : * attempt to obtain another state object ran into a &drm_modeset_lock
836 : * deadlock.
837 : */
838 : int (*atomic_check)(struct drm_encoder *encoder,
839 : struct drm_crtc_state *crtc_state,
840 : struct drm_connector_state *conn_state);
841 : };
842 :
843 : /**
844 : * drm_encoder_helper_add - sets the helper vtable for an encoder
845 : * @encoder: DRM encoder
846 : * @funcs: helper vtable to set for @encoder
847 : */
848 : static inline void drm_encoder_helper_add(struct drm_encoder *encoder,
849 : const struct drm_encoder_helper_funcs *funcs)
850 : {
851 0 : encoder->helper_private = funcs;
852 : }
853 :
854 : /**
855 : * struct drm_connector_helper_funcs - helper operations for connectors
856 : *
857 : * These functions are used by the atomic and legacy modeset helpers and by the
858 : * probe helpers.
859 : */
860 : struct drm_connector_helper_funcs {
861 : /**
862 : * @get_modes:
863 : *
864 : * This function should fill in all modes currently valid for the sink
865 : * into the &drm_connector.probed_modes list. It should also update the
866 : * EDID property by calling drm_connector_update_edid_property().
867 : *
868 : * The usual way to implement this is to cache the EDID retrieved in the
869 : * probe callback somewhere in the driver-private connector structure.
870 : * In this function drivers then parse the modes in the EDID and add
871 : * them by calling drm_add_edid_modes(). But connectors that drive a
872 : * fixed panel can also manually add specific modes using
873 : * drm_mode_probed_add(). Drivers which manually add modes should also
874 : * make sure that the &drm_connector.display_info,
875 : * &drm_connector.width_mm and &drm_connector.height_mm fields are
876 : * filled in.
877 : *
878 : * Note that the caller function will automatically add standard VESA
879 : * DMT modes up to 1024x768 if the .get_modes() helper operation returns
880 : * no mode and if the connector status is connector_status_connected or
881 : * connector_status_unknown. There is no need to call
882 : * drm_add_modes_noedid() manually in that case.
883 : *
884 : * Virtual drivers that just want some standard VESA mode with a given
885 : * resolution can call drm_add_modes_noedid(), and mark the preferred
886 : * one using drm_set_preferred_mode().
887 : *
888 : * This function is only called after the @detect hook has indicated
889 : * that a sink is connected and when the EDID isn't overridden through
890 : * sysfs or the kernel commandline.
891 : *
892 : * This callback is used by the probe helpers in e.g.
893 : * drm_helper_probe_single_connector_modes().
894 : *
895 : * To avoid races with concurrent connector state updates, the helper
896 : * libraries always call this with the &drm_mode_config.connection_mutex
897 : * held. Because of this it's safe to inspect &drm_connector->state.
898 : *
899 : * RETURNS:
900 : *
901 : * The number of modes added by calling drm_mode_probed_add().
902 : */
903 : int (*get_modes)(struct drm_connector *connector);
904 :
905 : /**
906 : * @detect_ctx:
907 : *
908 : * Check to see if anything is attached to the connector. The parameter
909 : * force is set to false whilst polling, true when checking the
910 : * connector due to a user request. force can be used by the driver to
911 : * avoid expensive, destructive operations during automated probing.
912 : *
913 : * This callback is optional, if not implemented the connector will be
914 : * considered as always being attached.
915 : *
916 : * This is the atomic version of &drm_connector_funcs.detect.
917 : *
918 : * To avoid races against concurrent connector state updates, the
919 : * helper libraries always call this with ctx set to a valid context,
920 : * and &drm_mode_config.connection_mutex will always be locked with
921 : * the ctx parameter set to this ctx. This allows taking additional
922 : * locks as required.
923 : *
924 : * RETURNS:
925 : *
926 : * &drm_connector_status indicating the connector's status,
927 : * or the error code returned by drm_modeset_lock(), -EDEADLK.
928 : */
929 : int (*detect_ctx)(struct drm_connector *connector,
930 : struct drm_modeset_acquire_ctx *ctx,
931 : bool force);
932 :
933 : /**
934 : * @mode_valid:
935 : *
936 : * Callback to validate a mode for a connector, irrespective of the
937 : * specific display configuration.
938 : *
939 : * This callback is used by the probe helpers to filter the mode list
940 : * (which is usually derived from the EDID data block from the sink).
941 : * See e.g. drm_helper_probe_single_connector_modes().
942 : *
943 : * This function is optional.
944 : *
945 : * NOTE:
946 : *
947 : * This only filters the mode list supplied to userspace in the
948 : * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid,
949 : * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid,
950 : * which are also called by the atomic helpers from
951 : * drm_atomic_helper_check_modeset(). This allows userspace to force and
952 : * ignore sink constraint (like the pixel clock limits in the screen's
953 : * EDID), which is useful for e.g. testing, or working around a broken
954 : * EDID. Any source hardware constraint (which always need to be
955 : * enforced) therefore should be checked in one of the above callbacks,
956 : * and not this one here.
957 : *
958 : * To avoid races with concurrent connector state updates, the helper
959 : * libraries always call this with the &drm_mode_config.connection_mutex
960 : * held. Because of this it's safe to inspect &drm_connector->state.
961 : *
962 : * RETURNS:
963 : *
964 : * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum
965 : * drm_mode_status.
966 : */
967 : enum drm_mode_status (*mode_valid)(struct drm_connector *connector,
968 : struct drm_display_mode *mode);
969 :
970 : /**
971 : * @mode_valid_ctx:
972 : *
973 : * Callback to validate a mode for a connector, irrespective of the
974 : * specific display configuration.
975 : *
976 : * This callback is used by the probe helpers to filter the mode list
977 : * (which is usually derived from the EDID data block from the sink).
978 : * See e.g. drm_helper_probe_single_connector_modes().
979 : *
980 : * This function is optional, and is the atomic version of
981 : * &drm_connector_helper_funcs.mode_valid.
982 : *
983 : * To allow for accessing the atomic state of modesetting objects, the
984 : * helper libraries always call this with ctx set to a valid context,
985 : * and &drm_mode_config.connection_mutex will always be locked with
986 : * the ctx parameter set to @ctx. This allows for taking additional
987 : * locks as required.
988 : *
989 : * Even though additional locks may be acquired, this callback is
990 : * still expected not to take any constraints into account which would
991 : * be influenced by the currently set display state - such constraints
992 : * should be handled in the driver's atomic check. For example, if a
993 : * connector shares display bandwidth with other connectors then it
994 : * would be ok to validate the minimum bandwidth requirement of a mode
995 : * against the maximum possible bandwidth of the connector. But it
996 : * wouldn't be ok to take the current bandwidth usage of other
997 : * connectors into account, as this would change depending on the
998 : * display state.
999 : *
1000 : * Returns:
1001 : * 0 if &drm_connector_helper_funcs.mode_valid_ctx succeeded and wrote
1002 : * the &enum drm_mode_status value to @status, or a negative error
1003 : * code otherwise.
1004 : *
1005 : */
1006 : int (*mode_valid_ctx)(struct drm_connector *connector,
1007 : struct drm_display_mode *mode,
1008 : struct drm_modeset_acquire_ctx *ctx,
1009 : enum drm_mode_status *status);
1010 :
1011 : /**
1012 : * @best_encoder:
1013 : *
1014 : * This function should select the best encoder for the given connector.
1015 : *
1016 : * This function is used by both the atomic helpers (in the
1017 : * drm_atomic_helper_check_modeset() function) and in the legacy CRTC
1018 : * helpers.
1019 : *
1020 : * NOTE:
1021 : *
1022 : * In atomic drivers this function is called in the check phase of an
1023 : * atomic update. The driver is not allowed to change or inspect
1024 : * anything outside of arguments passed-in. Atomic drivers which need to
1025 : * inspect dynamic configuration state should instead use
1026 : * @atomic_best_encoder.
1027 : *
1028 : * You can leave this function to NULL if the connector is only
1029 : * attached to a single encoder. In this case, the core will call
1030 : * drm_connector_get_single_encoder() for you.
1031 : *
1032 : * RETURNS:
1033 : *
1034 : * Encoder that should be used for the given connector and connector
1035 : * state, or NULL if no suitable encoder exists. Note that the helpers
1036 : * will ensure that encoders aren't used twice, drivers should not check
1037 : * for this.
1038 : */
1039 : struct drm_encoder *(*best_encoder)(struct drm_connector *connector);
1040 :
1041 : /**
1042 : * @atomic_best_encoder:
1043 : *
1044 : * This is the atomic version of @best_encoder for atomic drivers which
1045 : * need to select the best encoder depending upon the desired
1046 : * configuration and can't select it statically.
1047 : *
1048 : * This function is used by drm_atomic_helper_check_modeset().
1049 : * If it is not implemented, the core will fallback to @best_encoder
1050 : * (or drm_connector_get_single_encoder() if @best_encoder is NULL).
1051 : *
1052 : * NOTE:
1053 : *
1054 : * This function is called in the check phase of an atomic update. The
1055 : * driver is not allowed to change anything outside of the
1056 : * &drm_atomic_state update tracking structure passed in.
1057 : *
1058 : * RETURNS:
1059 : *
1060 : * Encoder that should be used for the given connector and connector
1061 : * state, or NULL if no suitable encoder exists. Note that the helpers
1062 : * will ensure that encoders aren't used twice, drivers should not check
1063 : * for this.
1064 : */
1065 : struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector,
1066 : struct drm_atomic_state *state);
1067 :
1068 : /**
1069 : * @atomic_check:
1070 : *
1071 : * This hook is used to validate connector state. This function is
1072 : * called from &drm_atomic_helper_check_modeset, and is called when
1073 : * a connector property is set, or a modeset on the crtc is forced.
1074 : *
1075 : * Because &drm_atomic_helper_check_modeset may be called multiple times,
1076 : * this function should handle being called multiple times as well.
1077 : *
1078 : * This function is also allowed to inspect any other object's state and
1079 : * can add more state objects to the atomic commit if needed. Care must
1080 : * be taken though to ensure that state check and compute functions for
1081 : * these added states are all called, and derived state in other objects
1082 : * all updated. Again the recommendation is to just call check helpers
1083 : * until a maximal configuration is reached.
1084 : *
1085 : * NOTE:
1086 : *
1087 : * This function is called in the check phase of an atomic update. The
1088 : * driver is not allowed to change anything outside of the free-standing
1089 : * state objects passed-in or assembled in the overall &drm_atomic_state
1090 : * update tracking structure.
1091 : *
1092 : * RETURNS:
1093 : *
1094 : * 0 on success, -EINVAL if the state or the transition can't be
1095 : * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
1096 : * attempt to obtain another state object ran into a &drm_modeset_lock
1097 : * deadlock.
1098 : */
1099 : int (*atomic_check)(struct drm_connector *connector,
1100 : struct drm_atomic_state *state);
1101 :
1102 : /**
1103 : * @atomic_commit:
1104 : *
1105 : * This hook is to be used by drivers implementing writeback connectors
1106 : * that need a point when to commit the writeback job to the hardware.
1107 : * The writeback_job to commit is available in the new connector state,
1108 : * in &drm_connector_state.writeback_job.
1109 : *
1110 : * This hook is optional.
1111 : *
1112 : * This callback is used by the atomic modeset helpers.
1113 : */
1114 : void (*atomic_commit)(struct drm_connector *connector,
1115 : struct drm_atomic_state *state);
1116 :
1117 : /**
1118 : * @prepare_writeback_job:
1119 : *
1120 : * As writeback jobs contain a framebuffer, drivers may need to
1121 : * prepare and clean them up the same way they can prepare and
1122 : * clean up framebuffers for planes. This optional connector operation
1123 : * is used to support the preparation of writeback jobs. The job
1124 : * prepare operation is called from drm_atomic_helper_prepare_planes()
1125 : * for struct &drm_writeback_connector connectors only.
1126 : *
1127 : * This operation is optional.
1128 : *
1129 : * This callback is used by the atomic modeset helpers.
1130 : */
1131 : int (*prepare_writeback_job)(struct drm_writeback_connector *connector,
1132 : struct drm_writeback_job *job);
1133 : /**
1134 : * @cleanup_writeback_job:
1135 : *
1136 : * This optional connector operation is used to support the
1137 : * cleanup of writeback jobs. The job cleanup operation is called
1138 : * from the existing drm_writeback_cleanup_job() function, invoked
1139 : * both when destroying the job as part of an aborted commit, or when
1140 : * the job completes.
1141 : *
1142 : * This operation is optional.
1143 : *
1144 : * This callback is used by the atomic modeset helpers.
1145 : */
1146 : void (*cleanup_writeback_job)(struct drm_writeback_connector *connector,
1147 : struct drm_writeback_job *job);
1148 :
1149 : /**
1150 : * @enable_hpd:
1151 : *
1152 : * Enable hot-plug detection for the connector.
1153 : *
1154 : * This operation is optional.
1155 : *
1156 : * This callback is used by the drm_kms_helper_poll_enable() helpers.
1157 : */
1158 : void (*enable_hpd)(struct drm_connector *connector);
1159 :
1160 : /**
1161 : * @disable_hpd:
1162 : *
1163 : * Disable hot-plug detection for the connector.
1164 : *
1165 : * This operation is optional.
1166 : *
1167 : * This callback is used by the drm_kms_helper_poll_disable() helpers.
1168 : */
1169 : void (*disable_hpd)(struct drm_connector *connector);
1170 : };
1171 :
1172 : /**
1173 : * drm_connector_helper_add - sets the helper vtable for a connector
1174 : * @connector: DRM connector
1175 : * @funcs: helper vtable to set for @connector
1176 : */
1177 : static inline void drm_connector_helper_add(struct drm_connector *connector,
1178 : const struct drm_connector_helper_funcs *funcs)
1179 : {
1180 0 : connector->helper_private = funcs;
1181 : }
1182 :
1183 : /**
1184 : * struct drm_plane_helper_funcs - helper operations for planes
1185 : *
1186 : * These functions are used by the atomic helpers.
1187 : */
1188 : struct drm_plane_helper_funcs {
1189 : /**
1190 : * @prepare_fb:
1191 : *
1192 : * This hook is to prepare a framebuffer for scanout by e.g. pinning
1193 : * its backing storage or relocating it into a contiguous block of
1194 : * VRAM. Other possible preparatory work includes flushing caches.
1195 : *
1196 : * This function must not block for outstanding rendering, since it is
1197 : * called in the context of the atomic IOCTL even for async commits to
1198 : * be able to return any errors to userspace. Instead the recommended
1199 : * way is to fill out the &drm_plane_state.fence of the passed-in
1200 : * &drm_plane_state. If the driver doesn't support native fences then
1201 : * equivalent functionality should be implemented through private
1202 : * members in the plane structure.
1203 : *
1204 : * For GEM drivers who neither have a @prepare_fb nor @cleanup_fb hook
1205 : * set drm_gem_plane_helper_prepare_fb() is called automatically to
1206 : * implement this. Other drivers which need additional plane processing
1207 : * can call drm_gem_plane_helper_prepare_fb() from their @prepare_fb
1208 : * hook.
1209 : *
1210 : * The resources acquired in @prepare_fb persist after the end of
1211 : * the atomic commit. Resources that can be release at the commit's end
1212 : * should be acquired in @begin_fb_access and released in @end_fb_access.
1213 : * For example, a GEM buffer's pin operation belongs into @prepare_fb to
1214 : * keep the buffer pinned after the commit. But a vmap operation for
1215 : * shadow-plane helpers belongs into @begin_fb_access, so that atomic
1216 : * helpers remove the mapping at the end of the commit.
1217 : *
1218 : * The helpers will call @cleanup_fb with matching arguments for every
1219 : * successful call to this hook.
1220 : *
1221 : * This callback is used by the atomic modeset helpers, but it is
1222 : * optional. See @begin_fb_access for preparing per-commit resources.
1223 : *
1224 : * RETURNS:
1225 : *
1226 : * 0 on success or one of the following negative error codes allowed by
1227 : * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers
1228 : * this callback is the only one which can fail an atomic commit,
1229 : * everything else must complete successfully.
1230 : */
1231 : int (*prepare_fb)(struct drm_plane *plane,
1232 : struct drm_plane_state *new_state);
1233 : /**
1234 : * @cleanup_fb:
1235 : *
1236 : * This hook is called to clean up any resources allocated for the given
1237 : * framebuffer and plane configuration in @prepare_fb.
1238 : *
1239 : * This callback is used by the atomic modeset helpers, but it is
1240 : * optional.
1241 : */
1242 : void (*cleanup_fb)(struct drm_plane *plane,
1243 : struct drm_plane_state *old_state);
1244 :
1245 : /**
1246 : * @begin_fb_access:
1247 : *
1248 : * This hook prepares the plane for access during an atomic commit.
1249 : * In contrast to @prepare_fb, resources acquired in @begin_fb_access,
1250 : * are released at the end of the atomic commit in @end_fb_access.
1251 : *
1252 : * For example, with shadow-plane helpers, the GEM buffer's vmap
1253 : * operation belongs into @begin_fb_access, so that the buffer's
1254 : * memory will be unmapped at the end of the commit in @end_fb_access.
1255 : * But a GEM buffer's pin operation belongs into @prepare_fb
1256 : * to keep the buffer pinned after the commit.
1257 : *
1258 : * The callback is used by the atomic modeset helpers, but it is optional.
1259 : * See @end_fb_cleanup for undoing the effects of @begin_fb_access and
1260 : * @prepare_fb for acquiring resources until the next pageflip.
1261 : *
1262 : * Returns:
1263 : * 0 on success, or a negative errno code otherwise.
1264 : */
1265 : int (*begin_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state);
1266 :
1267 : /**
1268 : * @end_fb_access:
1269 : *
1270 : * This hook cleans up resources allocated by @begin_fb_access. It it called
1271 : * at the end of a commit for the new plane state.
1272 : */
1273 : void (*end_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state);
1274 :
1275 : /**
1276 : * @atomic_check:
1277 : *
1278 : * Drivers should check plane specific constraints in this hook.
1279 : *
1280 : * When using drm_atomic_helper_check_planes() plane's @atomic_check
1281 : * hooks are called before the ones for CRTCs, which allows drivers to
1282 : * request shared resources that the CRTC controls here. For more
1283 : * complicated dependencies the driver can call the provided check helpers
1284 : * multiple times until the computed state has a final configuration and
1285 : * everything has been checked.
1286 : *
1287 : * This function is also allowed to inspect any other object's state and
1288 : * can add more state objects to the atomic commit if needed. Care must
1289 : * be taken though to ensure that state check and compute functions for
1290 : * these added states are all called, and derived state in other objects
1291 : * all updated. Again the recommendation is to just call check helpers
1292 : * until a maximal configuration is reached.
1293 : *
1294 : * This callback is used by the atomic modeset helpers, but it is
1295 : * optional.
1296 : *
1297 : * NOTE:
1298 : *
1299 : * This function is called in the check phase of an atomic update. The
1300 : * driver is not allowed to change anything outside of the
1301 : * &drm_atomic_state update tracking structure.
1302 : *
1303 : * RETURNS:
1304 : *
1305 : * 0 on success, -EINVAL if the state or the transition can't be
1306 : * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
1307 : * attempt to obtain another state object ran into a &drm_modeset_lock
1308 : * deadlock.
1309 : */
1310 : int (*atomic_check)(struct drm_plane *plane,
1311 : struct drm_atomic_state *state);
1312 :
1313 : /**
1314 : * @atomic_update:
1315 : *
1316 : * Drivers should use this function to update the plane state. This
1317 : * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and
1318 : * drm_crtc_helper_funcs.atomic_flush callbacks.
1319 : *
1320 : * Note that the power state of the display pipe when this function is
1321 : * called depends upon the exact helpers and calling sequence the driver
1322 : * has picked. See drm_atomic_helper_commit_planes() for a discussion of
1323 : * the tradeoffs and variants of plane commit helpers.
1324 : *
1325 : * This callback is used by the atomic modeset helpers, but it is optional.
1326 : */
1327 : void (*atomic_update)(struct drm_plane *plane,
1328 : struct drm_atomic_state *state);
1329 :
1330 : /**
1331 : * @atomic_enable:
1332 : *
1333 : * Drivers should use this function to unconditionally enable a plane.
1334 : * This hook is called in-between the &drm_crtc_helper_funcs.atomic_begin
1335 : * and drm_crtc_helper_funcs.atomic_flush callbacks. It is called after
1336 : * @atomic_update, which will be called for all enabled planes. Drivers
1337 : * that use @atomic_enable should set up a plane in @atomic_update and
1338 : * afterwards enable the plane in @atomic_enable. If a plane needs to be
1339 : * enabled before installing the scanout buffer, drivers can still do
1340 : * so in @atomic_update.
1341 : *
1342 : * Note that the power state of the display pipe when this function is
1343 : * called depends upon the exact helpers and calling sequence the driver
1344 : * has picked. See drm_atomic_helper_commit_planes() for a discussion of
1345 : * the tradeoffs and variants of plane commit helpers.
1346 : *
1347 : * This callback is used by the atomic modeset helpers, but it is
1348 : * optional. If implemented, @atomic_enable should be the inverse of
1349 : * @atomic_disable. Drivers that don't want to use either can still
1350 : * implement the complete plane update in @atomic_update.
1351 : */
1352 : void (*atomic_enable)(struct drm_plane *plane,
1353 : struct drm_atomic_state *state);
1354 :
1355 : /**
1356 : * @atomic_disable:
1357 : *
1358 : * Drivers should use this function to unconditionally disable a plane.
1359 : * This hook is called in-between the
1360 : * &drm_crtc_helper_funcs.atomic_begin and
1361 : * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to
1362 : * @atomic_update, which will be called for disabling planes, too, if
1363 : * the @atomic_disable hook isn't implemented.
1364 : *
1365 : * This hook is also useful to disable planes in preparation of a modeset,
1366 : * by calling drm_atomic_helper_disable_planes_on_crtc() from the
1367 : * &drm_crtc_helper_funcs.disable hook.
1368 : *
1369 : * Note that the power state of the display pipe when this function is
1370 : * called depends upon the exact helpers and calling sequence the driver
1371 : * has picked. See drm_atomic_helper_commit_planes() for a discussion of
1372 : * the tradeoffs and variants of plane commit helpers.
1373 : *
1374 : * This callback is used by the atomic modeset helpers, but it is
1375 : * optional. It's intended to reverse the effects of @atomic_enable.
1376 : */
1377 : void (*atomic_disable)(struct drm_plane *plane,
1378 : struct drm_atomic_state *state);
1379 :
1380 : /**
1381 : * @atomic_async_check:
1382 : *
1383 : * Drivers should set this function pointer to check if the plane's
1384 : * atomic state can be updated in a async fashion. Here async means
1385 : * "not vblank synchronized".
1386 : *
1387 : * This hook is called by drm_atomic_async_check() to establish if a
1388 : * given update can be committed asynchronously, that is, if it can
1389 : * jump ahead of the state currently queued for update.
1390 : *
1391 : * RETURNS:
1392 : *
1393 : * Return 0 on success and any error returned indicates that the update
1394 : * can not be applied in asynchronous manner.
1395 : */
1396 : int (*atomic_async_check)(struct drm_plane *plane,
1397 : struct drm_atomic_state *state);
1398 :
1399 : /**
1400 : * @atomic_async_update:
1401 : *
1402 : * Drivers should set this function pointer to perform asynchronous
1403 : * updates of planes, that is, jump ahead of the currently queued
1404 : * state and update the plane. Here async means "not vblank
1405 : * synchronized".
1406 : *
1407 : * This hook is called by drm_atomic_helper_async_commit().
1408 : *
1409 : * An async update will happen on legacy cursor updates. An async
1410 : * update won't happen if there is an outstanding commit modifying
1411 : * the same plane.
1412 : *
1413 : * When doing async_update drivers shouldn't replace the
1414 : * &drm_plane_state but update the current one with the new plane
1415 : * configurations in the new plane_state.
1416 : *
1417 : * Drivers should also swap the framebuffers between current plane
1418 : * state (&drm_plane.state) and new_state.
1419 : * This is required since cleanup for async commits is performed on
1420 : * the new state, rather than old state like for traditional commits.
1421 : * Since we want to give up the reference on the current (old) fb
1422 : * instead of our brand new one, swap them in the driver during the
1423 : * async commit.
1424 : *
1425 : * FIXME:
1426 : * - It only works for single plane updates
1427 : * - Async Pageflips are not supported yet
1428 : * - Some hw might still scan out the old buffer until the next
1429 : * vblank, however we let go of the fb references as soon as
1430 : * we run this hook. For now drivers must implement their own workers
1431 : * for deferring if needed, until a common solution is created.
1432 : */
1433 : void (*atomic_async_update)(struct drm_plane *plane,
1434 : struct drm_atomic_state *state);
1435 : };
1436 :
1437 : /**
1438 : * drm_plane_helper_add - sets the helper vtable for a plane
1439 : * @plane: DRM plane
1440 : * @funcs: helper vtable to set for @plane
1441 : */
1442 : static inline void drm_plane_helper_add(struct drm_plane *plane,
1443 : const struct drm_plane_helper_funcs *funcs)
1444 : {
1445 0 : plane->helper_private = funcs;
1446 : }
1447 :
1448 : /**
1449 : * struct drm_mode_config_helper_funcs - global modeset helper operations
1450 : *
1451 : * These helper functions are used by the atomic helpers.
1452 : */
1453 : struct drm_mode_config_helper_funcs {
1454 : /**
1455 : * @atomic_commit_tail:
1456 : *
1457 : * This hook is used by the default atomic_commit() hook implemented in
1458 : * drm_atomic_helper_commit() together with the nonblocking commit
1459 : * helpers (see drm_atomic_helper_setup_commit() for a starting point)
1460 : * to implement blocking and nonblocking commits easily. It is not used
1461 : * by the atomic helpers
1462 : *
1463 : * This function is called when the new atomic state has already been
1464 : * swapped into the various state pointers. The passed in state
1465 : * therefore contains copies of the old/previous state. This hook should
1466 : * commit the new state into hardware. Note that the helpers have
1467 : * already waited for preceeding atomic commits and fences, but drivers
1468 : * can add more waiting calls at the start of their implementation, e.g.
1469 : * to wait for driver-internal request for implicit syncing, before
1470 : * starting to commit the update to the hardware.
1471 : *
1472 : * After the atomic update is committed to the hardware this hook needs
1473 : * to call drm_atomic_helper_commit_hw_done(). Then wait for the update
1474 : * to be executed by the hardware, for example using
1475 : * drm_atomic_helper_wait_for_vblanks() or
1476 : * drm_atomic_helper_wait_for_flip_done(), and then clean up the old
1477 : * framebuffers using drm_atomic_helper_cleanup_planes().
1478 : *
1479 : * When disabling a CRTC this hook _must_ stall for the commit to
1480 : * complete. Vblank waits don't work on disabled CRTC, hence the core
1481 : * can't take care of this. And it also can't rely on the vblank event,
1482 : * since that can be signalled already when the screen shows black,
1483 : * which can happen much earlier than the last hardware access needed to
1484 : * shut off the display pipeline completely.
1485 : *
1486 : * This hook is optional, the default implementation is
1487 : * drm_atomic_helper_commit_tail().
1488 : */
1489 : void (*atomic_commit_tail)(struct drm_atomic_state *state);
1490 :
1491 : /**
1492 : * @atomic_commit_setup:
1493 : *
1494 : * This hook is used by the default atomic_commit() hook implemented in
1495 : * drm_atomic_helper_commit() together with the nonblocking helpers (see
1496 : * drm_atomic_helper_setup_commit()) to extend the DRM commit setup. It
1497 : * is not used by the atomic helpers.
1498 : *
1499 : * This function is called at the end of
1500 : * drm_atomic_helper_setup_commit(), so once the commit has been
1501 : * properly setup across the generic DRM object states. It allows
1502 : * drivers to do some additional commit tracking that isn't related to a
1503 : * CRTC, plane or connector, tracked in a &drm_private_obj structure.
1504 : *
1505 : * Note that the documentation of &drm_private_obj has more details on
1506 : * how one should implement this.
1507 : *
1508 : * This hook is optional.
1509 : */
1510 : int (*atomic_commit_setup)(struct drm_atomic_state *state);
1511 : };
1512 :
1513 : #endif
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