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