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>
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:
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
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.
29 #ifndef __DRM_MODESET_HELPER_VTABLES_H__
30 #define __DRM_MODESET_HELPER_VTABLES_H__
32 #include <drm/drm_crtc.h>
33 #include <drm/drm_encoder.h>
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.
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
48 * To make this clear all the helper vtables are pulled together in this location here.
54 * struct drm_crtc_helper_funcs - helper operations for CRTCs
56 * These hooks are used by the legacy CRTC helpers, the transitional plane
57 * helpers and the new atomic modesetting helpers.
59 struct drm_crtc_helper_funcs {
63 * Callback to control power levels on the CRTC. If the mode passed in
64 * is unsupported, the provider must use the next lowest power level.
65 * This is used by the legacy CRTC helpers to implement DPMS
66 * functionality in drm_helper_connector_dpms().
68 * This callback is also used to disable a CRTC by calling it with
69 * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
71 * This callback is used by the legacy CRTC helpers. Atomic helpers
72 * also support using this hook for enabling and disabling a CRTC to
73 * facilitate transitions to atomic, but it is deprecated. Instead
74 * @atomic_enable and @atomic_disable should be used.
76 void (*dpms)(struct drm_crtc *crtc, int mode);
81 * This callback should prepare the CRTC for a subsequent modeset, which
82 * in practice means the driver should disable the CRTC if it is
83 * running. Most drivers ended up implementing this by calling their
84 * @dpms hook with DRM_MODE_DPMS_OFF.
86 * This callback is used by the legacy CRTC helpers. Atomic helpers
87 * also support using this hook for disabling a CRTC to facilitate
88 * transitions to atomic, but it is deprecated. Instead @atomic_disable
91 void (*prepare)(struct drm_crtc *crtc);
96 * This callback should commit the new mode on the CRTC after a modeset,
97 * which in practice means the driver should enable the CRTC. Most
98 * drivers ended up implementing this by calling their @dpms hook with
101 * This callback is used by the legacy CRTC helpers. Atomic helpers
102 * also support using this hook for enabling a CRTC to facilitate
103 * transitions to atomic, but it is deprecated. Instead @atomic_enable
106 void (*commit)(struct drm_crtc *crtc);
111 * This callback is used to check if a specific mode is valid in this
112 * crtc. This should be implemented if the crtc has some sort of
113 * restriction in the modes it can display. For example, a given crtc
114 * may be responsible to set a clock value. If the clock can not
115 * produce all the values for the available modes then this callback
116 * can be used to restrict the number of modes to only the ones that
119 * This hook is used by the probe helpers to filter the mode list in
120 * drm_helper_probe_single_connector_modes(), and it is used by the
121 * atomic helpers to validate modes supplied by userspace in
122 * drm_atomic_helper_check_modeset().
124 * This function is optional.
128 * Since this function is both called from the check phase of an atomic
129 * commit, and the mode validation in the probe paths it is not allowed
130 * to look at anything else but the passed-in mode, and validate it
131 * against configuration-invariant hardward constraints. Any further
132 * limits which depend upon the configuration can only be checked in
133 * @mode_fixup or @atomic_check.
137 * drm_mode_status Enum
139 enum drm_mode_status (*mode_valid)(struct drm_crtc *crtc,
140 const struct drm_display_mode *mode);
145 * This callback is used to validate a mode. The parameter mode is the
146 * display mode that userspace requested, adjusted_mode is the mode the
147 * encoders need to be fed with. Note that this is the inverse semantics
148 * of the meaning for the &drm_encoder and &drm_bridge_funcs.mode_fixup
149 * vfunc. If the CRTC cannot support the requested conversion from mode
150 * to adjusted_mode it should reject the modeset. See also
151 * &drm_crtc_state.adjusted_mode for more details.
153 * This function is used by both legacy CRTC helpers and atomic helpers.
154 * With atomic helpers it is optional.
158 * This function is called in the check phase of atomic modesets, which
159 * can be aborted for any reason (including on userspace's request to
160 * just check whether a configuration would be possible). Atomic drivers
161 * MUST NOT touch any persistent state (hardware or software) or data
162 * structures except the passed in adjusted_mode parameter.
164 * This is in contrast to the legacy CRTC helpers where this was
167 * Atomic drivers which need to inspect and adjust more state should
168 * instead use the @atomic_check callback, but note that they're not
169 * perfectly equivalent: @mode_valid is called from
170 * drm_atomic_helper_check_modeset(), but @atomic_check is called from
171 * drm_atomic_helper_check_planes(), because originally it was meant for
172 * plane update checks only.
174 * Also beware that userspace can request its own custom modes, neither
175 * core nor helpers filter modes to the list of probe modes reported by
176 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
177 * that modes are filtered consistently put any CRTC constraints and
178 * limits checks into @mode_valid.
182 * True if an acceptable configuration is possible, false if the modeset
183 * operation should be rejected.
185 bool (*mode_fixup)(struct drm_crtc *crtc,
186 const struct drm_display_mode *mode,
187 struct drm_display_mode *adjusted_mode);
192 * This callback is used by the legacy CRTC helpers to set a new mode,
193 * position and framebuffer. Since it ties the primary plane to every
194 * mode change it is incompatible with universal plane support. And
195 * since it can't update other planes it's incompatible with atomic
198 * This callback is only used by CRTC helpers and deprecated.
202 * 0 on success or a negative error code on failure.
204 int (*mode_set)(struct drm_crtc *crtc, struct drm_display_mode *mode,
205 struct drm_display_mode *adjusted_mode, int x, int y,
206 struct drm_framebuffer *old_fb);
211 * This callback is used to update the display mode of a CRTC without
212 * changing anything of the primary plane configuration. This fits the
213 * requirement of atomic and hence is used by the atomic helpers. It is
214 * also used by the transitional plane helpers to implement a
215 * @mode_set hook in drm_helper_crtc_mode_set().
217 * Note that the display pipe is completely off when this function is
218 * called. Atomic drivers which need hardware to be running before they
219 * program the new display mode (e.g. because they implement runtime PM)
220 * should not use this hook. This is because the helper library calls
221 * this hook only once per mode change and not every time the display
222 * pipeline is suspended using either DPMS or the new "ACTIVE" property.
223 * Which means register values set in this callback might get reset when
224 * the CRTC is suspended, but not restored. Such drivers should instead
225 * move all their CRTC setup into the @atomic_enable callback.
227 * This callback is optional.
229 void (*mode_set_nofb)(struct drm_crtc *crtc);
234 * This callback is used by the legacy CRTC helpers to set a new
235 * framebuffer and scanout position. It is optional and used as an
236 * optimized fast-path instead of a full mode set operation with all the
237 * resulting flickering. If it is not present
238 * drm_crtc_helper_set_config() will fall back to a full modeset, using
239 * the @mode_set callback. Since it can't update other planes it's
240 * incompatible with atomic modeset support.
242 * This callback is only used by the CRTC helpers and deprecated.
246 * 0 on success or a negative error code on failure.
248 int (*mode_set_base)(struct drm_crtc *crtc, int x, int y,
249 struct drm_framebuffer *old_fb);
252 * @mode_set_base_atomic:
254 * This callback is used by the fbdev helpers to set a new framebuffer
255 * and scanout without sleeping, i.e. from an atomic calling context. It
256 * is only used to implement kgdb support.
258 * This callback is optional and only needed for kgdb support in the fbdev
263 * 0 on success or a negative error code on failure.
265 int (*mode_set_base_atomic)(struct drm_crtc *crtc,
266 struct drm_framebuffer *fb, int x, int y,
267 enum mode_set_atomic);
272 * This callback should be used to disable the CRTC. With the atomic
273 * drivers it is called after all encoders connected to this CRTC have
274 * been shut off already using their own
275 * &drm_encoder_helper_funcs.disable hook. If that sequence is too
276 * simple drivers can just add their own hooks and call it from this
277 * CRTC callback here by looping over all encoders connected to it using
278 * for_each_encoder_on_crtc().
280 * This hook is used both by legacy CRTC helpers and atomic helpers.
281 * Atomic drivers don't need to implement it if there's no need to
282 * disable anything at the CRTC level. To ensure that runtime PM
283 * handling (using either DPMS or the new "ACTIVE" property) works
284 * @disable must be the inverse of @atomic_enable for atomic drivers.
285 * Atomic drivers should consider to use @atomic_disable instead of
290 * With legacy CRTC helpers there's a big semantic difference between
291 * @disable and other hooks (like @prepare or @dpms) used to shut down a
292 * CRTC: @disable is only called when also logically disabling the
293 * display pipeline and needs to release any resources acquired in
294 * @mode_set (like shared PLLs, or again release pinned framebuffers).
296 * Therefore @disable must be the inverse of @mode_set plus @commit for
297 * drivers still using legacy CRTC helpers, which is different from the
298 * rules under atomic.
300 void (*disable)(struct drm_crtc *crtc);
305 * Drivers should check plane-update related CRTC constraints in this
306 * hook. They can also check mode related limitations but need to be
307 * aware of the calling order, since this hook is used by
308 * drm_atomic_helper_check_planes() whereas the preparations needed to
309 * check output routing and the display mode is done in
310 * drm_atomic_helper_check_modeset(). Therefore drivers that want to
311 * check output routing and display mode constraints in this callback
312 * must ensure that drm_atomic_helper_check_modeset() has been called
313 * beforehand. This is calling order used by the default helper
314 * implementation in drm_atomic_helper_check().
316 * When using drm_atomic_helper_check_planes() this hook is called
317 * after the &drm_plane_helper_funcs.atomic_check hook for planes, which
318 * allows drivers to assign shared resources requested by planes in this
319 * callback here. For more complicated dependencies the driver can call
320 * the provided check helpers multiple times until the computed state
321 * has a final configuration and everything has been checked.
323 * This function is also allowed to inspect any other object's state and
324 * can add more state objects to the atomic commit if needed. Care must
325 * be taken though to ensure that state check and compute functions for
326 * these added states are all called, and derived state in other objects
327 * all updated. Again the recommendation is to just call check helpers
328 * until a maximal configuration is reached.
330 * This callback is used by the atomic modeset helpers and by the
331 * transitional plane helpers, but it is optional.
335 * This function is called in the check phase of an atomic update. The
336 * driver is not allowed to change anything outside of the free-standing
337 * state objects passed-in or assembled in the overall &drm_atomic_state
338 * update tracking structure.
340 * Also beware that userspace can request its own custom modes, neither
341 * core nor helpers filter modes to the list of probe modes reported by
342 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
343 * that modes are filtered consistently put any CRTC constraints and
344 * limits checks into @mode_valid.
348 * 0 on success, -EINVAL if the state or the transition can't be
349 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
350 * attempt to obtain another state object ran into a &drm_modeset_lock
353 int (*atomic_check)(struct drm_crtc *crtc,
354 struct drm_crtc_state *state);
359 * Drivers should prepare for an atomic update of multiple planes on
360 * a CRTC in this hook. Depending upon hardware this might be vblank
361 * evasion, blocking updates by setting bits or doing preparatory work
362 * for e.g. manual update display.
364 * This hook is called before any plane commit functions are called.
366 * Note that the power state of the display pipe when this function is
367 * called depends upon the exact helpers and calling sequence the driver
368 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
369 * the tradeoffs and variants of plane commit helpers.
371 * This callback is used by the atomic modeset helpers and by the
372 * transitional plane helpers, but it is optional.
374 void (*atomic_begin)(struct drm_crtc *crtc,
375 struct drm_crtc_state *old_crtc_state);
379 * Drivers should finalize an atomic update of multiple planes on
380 * a CRTC in this hook. Depending upon hardware this might include
381 * checking that vblank evasion was successful, unblocking updates by
382 * setting bits or setting the GO bit to flush out all updates.
384 * Simple hardware or hardware with special requirements can commit and
385 * flush out all updates for all planes from this hook and forgo all the
386 * other commit hooks for plane updates.
388 * This hook is called after any plane commit functions are called.
390 * Note that the power state of the display pipe when this function is
391 * called depends upon the exact helpers and calling sequence the driver
392 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
393 * the tradeoffs and variants of plane commit helpers.
395 * This callback is used by the atomic modeset helpers and by the
396 * transitional plane helpers, but it is optional.
398 void (*atomic_flush)(struct drm_crtc *crtc,
399 struct drm_crtc_state *old_crtc_state);
404 * This callback should be used to enable the CRTC. With the atomic
405 * drivers it is called before all encoders connected to this CRTC are
406 * enabled through the encoder's own &drm_encoder_helper_funcs.enable
407 * hook. If that sequence is too simple drivers can just add their own
408 * hooks and call it from this CRTC callback here by looping over all
409 * encoders connected to it using for_each_encoder_on_crtc().
411 * This hook is used only by atomic helpers, for symmetry with
412 * @atomic_disable. Atomic drivers don't need to implement it if there's
413 * no need to enable anything at the CRTC level. To ensure that runtime
414 * PM handling (using either DPMS or the new "ACTIVE" property) works
415 * @atomic_enable must be the inverse of @atomic_disable for atomic
418 * Drivers can use the @old_crtc_state input parameter if the operations
419 * needed to enable the CRTC don't depend solely on the new state but
420 * also on the transition between the old state and the new state.
422 * This function is optional.
424 void (*atomic_enable)(struct drm_crtc *crtc,
425 struct drm_crtc_state *old_crtc_state);
430 * This callback should be used to disable the CRTC. With the atomic
431 * drivers it is called after all encoders connected to this CRTC have
432 * been shut off already using their own
433 * &drm_encoder_helper_funcs.disable hook. If that sequence is too
434 * simple drivers can just add their own hooks and call it from this
435 * CRTC callback here by looping over all encoders connected to it using
436 * for_each_encoder_on_crtc().
438 * This hook is used only by atomic helpers. Atomic drivers don't
439 * need to implement it if there's no need to disable anything at the
442 * Comparing to @disable, this one provides the additional input
443 * parameter @old_crtc_state which could be used to access the old
444 * state. Atomic drivers should consider to use this one instead
447 * This function is optional.
449 void (*atomic_disable)(struct drm_crtc *crtc,
450 struct drm_crtc_state *old_crtc_state);
454 * drm_crtc_helper_add - sets the helper vtable for a crtc
456 * @funcs: helper vtable to set for @crtc
458 static inline void drm_crtc_helper_add(struct drm_crtc *crtc,
459 const struct drm_crtc_helper_funcs *funcs)
461 crtc->helper_private = funcs;
465 * struct drm_encoder_helper_funcs - helper operations for encoders
467 * These hooks are used by the legacy CRTC helpers, the transitional plane
468 * helpers and the new atomic modesetting helpers.
470 struct drm_encoder_helper_funcs {
474 * Callback to control power levels on the encoder. If the mode passed in
475 * is unsupported, the provider must use the next lowest power level.
476 * This is used by the legacy encoder helpers to implement DPMS
477 * functionality in drm_helper_connector_dpms().
479 * This callback is also used to disable an encoder by calling it with
480 * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
482 * This callback is used by the legacy CRTC helpers. Atomic helpers
483 * also support using this hook for enabling and disabling an encoder to
484 * facilitate transitions to atomic, but it is deprecated. Instead
485 * @enable and @disable should be used.
487 void (*dpms)(struct drm_encoder *encoder, int mode);
492 * This callback is used to check if a specific mode is valid in this
493 * encoder. This should be implemented if the encoder has some sort
494 * of restriction in the modes it can display. For example, a given
495 * encoder may be responsible to set a clock value. If the clock can
496 * not produce all the values for the available modes then this callback
497 * can be used to restrict the number of modes to only the ones that
500 * This hook is used by the probe helpers to filter the mode list in
501 * drm_helper_probe_single_connector_modes(), and it is used by the
502 * atomic helpers to validate modes supplied by userspace in
503 * drm_atomic_helper_check_modeset().
505 * This function is optional.
509 * Since this function is both called from the check phase of an atomic
510 * commit, and the mode validation in the probe paths it is not allowed
511 * to look at anything else but the passed-in mode, and validate it
512 * against configuration-invariant hardward constraints. Any further
513 * limits which depend upon the configuration can only be checked in
514 * @mode_fixup or @atomic_check.
518 * drm_mode_status Enum
520 enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc,
521 const struct drm_display_mode *mode);
526 * This callback is used to validate and adjust a mode. The parameter
527 * mode is the display mode that should be fed to the next element in
528 * the display chain, either the final &drm_connector or a &drm_bridge.
529 * The parameter adjusted_mode is the input mode the encoder requires. It
530 * can be modified by this callback and does not need to match mode. See
531 * also &drm_crtc_state.adjusted_mode for more details.
533 * This function is used by both legacy CRTC helpers and atomic helpers.
534 * This hook is optional.
538 * This function is called in the check phase of atomic modesets, which
539 * can be aborted for any reason (including on userspace's request to
540 * just check whether a configuration would be possible). Atomic drivers
541 * MUST NOT touch any persistent state (hardware or software) or data
542 * structures except the passed in adjusted_mode parameter.
544 * This is in contrast to the legacy CRTC helpers where this was
547 * Atomic drivers which need to inspect and adjust more state should
548 * instead use the @atomic_check callback. If @atomic_check is used,
549 * this hook isn't called since @atomic_check allows a strict superset
550 * of the functionality of @mode_fixup.
552 * Also beware that userspace can request its own custom modes, neither
553 * core nor helpers filter modes to the list of probe modes reported by
554 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
555 * that modes are filtered consistently put any encoder constraints and
556 * limits checks into @mode_valid.
560 * True if an acceptable configuration is possible, false if the modeset
561 * operation should be rejected.
563 bool (*mode_fixup)(struct drm_encoder *encoder,
564 const struct drm_display_mode *mode,
565 struct drm_display_mode *adjusted_mode);
570 * This callback should prepare the encoder for a subsequent modeset,
571 * which in practice means the driver should disable the encoder if it
572 * is running. Most drivers ended up implementing this by calling their
573 * @dpms hook with DRM_MODE_DPMS_OFF.
575 * This callback is used by the legacy CRTC helpers. Atomic helpers
576 * also support using this hook for disabling an encoder to facilitate
577 * transitions to atomic, but it is deprecated. Instead @disable should
580 void (*prepare)(struct drm_encoder *encoder);
585 * This callback should commit the new mode on the encoder after a modeset,
586 * which in practice means the driver should enable the encoder. Most
587 * drivers ended up implementing this by calling their @dpms hook with
590 * This callback is used by the legacy CRTC helpers. Atomic helpers
591 * also support using this hook for enabling an encoder to facilitate
592 * transitions to atomic, but it is deprecated. Instead @enable should
595 void (*commit)(struct drm_encoder *encoder);
600 * This callback is used to update the display mode of an encoder.
602 * Note that the display pipe is completely off when this function is
603 * called. Drivers which need hardware to be running before they program
604 * the new display mode (because they implement runtime PM) should not
605 * use this hook, because the helper library calls it only once and not
606 * every time the display pipeline is suspend using either DPMS or the
607 * new "ACTIVE" property. Such drivers should instead move all their
608 * encoder setup into the @enable callback.
610 * This callback is used both by the legacy CRTC helpers and the atomic
611 * modeset helpers. It is optional in the atomic helpers.
615 * If the driver uses the atomic modeset helpers and needs to inspect
616 * the connector state or connector display info during mode setting,
617 * @atomic_mode_set can be used instead.
619 void (*mode_set)(struct drm_encoder *encoder,
620 struct drm_display_mode *mode,
621 struct drm_display_mode *adjusted_mode);
626 * This callback is used to update the display mode of an encoder.
628 * Note that the display pipe is completely off when this function is
629 * called. Drivers which need hardware to be running before they program
630 * the new display mode (because they implement runtime PM) should not
631 * use this hook, because the helper library calls it only once and not
632 * every time the display pipeline is suspended using either DPMS or the
633 * new "ACTIVE" property. Such drivers should instead move all their
634 * encoder setup into the @enable callback.
636 * This callback is used by the atomic modeset helpers in place of the
637 * @mode_set callback, if set by the driver. It is optional and should
638 * be used instead of @mode_set if the driver needs to inspect the
639 * connector state or display info, since there is no direct way to
640 * go from the encoder to the current connector.
642 void (*atomic_mode_set)(struct drm_encoder *encoder,
643 struct drm_crtc_state *crtc_state,
644 struct drm_connector_state *conn_state);
649 * This callback is used by the legacy CRTC helpers to work around
650 * deficiencies in its own book-keeping.
652 * Do not use, use atomic helpers instead, which get the book keeping
657 * Currently only nouveau is using this, and as soon as nouveau is
658 * atomic we can ditch this hook.
660 struct drm_crtc *(*get_crtc)(struct drm_encoder *encoder);
665 * This callback can be used by drivers who want to do detection on the
666 * encoder object instead of in connector functions.
668 * It is not used by any helper and therefore has purely driver-specific
669 * semantics. New drivers shouldn't use this and instead just implement
670 * their own private callbacks.
674 * This should just be converted into a pile of driver vfuncs.
675 * Currently radeon, amdgpu and nouveau are using it.
677 enum drm_connector_status (*detect)(struct drm_encoder *encoder,
678 struct drm_connector *connector);
683 * This callback should be used to disable the encoder. With the atomic
684 * drivers it is called before this encoder's CRTC has been shut off
685 * using their own &drm_crtc_helper_funcs.disable hook. If that
686 * sequence is too simple drivers can just add their own driver private
687 * encoder hooks and call them from CRTC's callback by looping over all
688 * encoders connected to it using for_each_encoder_on_crtc().
690 * This hook is used both by legacy CRTC helpers and atomic helpers.
691 * Atomic drivers don't need to implement it if there's no need to
692 * disable anything at the encoder level. To ensure that runtime PM
693 * handling (using either DPMS or the new "ACTIVE" property) works
694 * @disable must be the inverse of @enable for atomic drivers.
698 * With legacy CRTC helpers there's a big semantic difference between
699 * @disable and other hooks (like @prepare or @dpms) used to shut down a
700 * encoder: @disable is only called when also logically disabling the
701 * display pipeline and needs to release any resources acquired in
702 * @mode_set (like shared PLLs, or again release pinned framebuffers).
704 * Therefore @disable must be the inverse of @mode_set plus @commit for
705 * drivers still using legacy CRTC helpers, which is different from the
706 * rules under atomic.
708 void (*disable)(struct drm_encoder *encoder);
713 * This callback should be used to enable the encoder. With the atomic
714 * drivers it is called after this encoder's CRTC has been enabled using
715 * their own &drm_crtc_helper_funcs.enable hook. If that sequence is
716 * too simple drivers can just add their own driver private encoder
717 * hooks and call them from CRTC's callback by looping over all encoders
718 * connected to it using for_each_encoder_on_crtc().
720 * This hook is used only by atomic helpers, for symmetry with @disable.
721 * Atomic drivers don't need to implement it if there's no need to
722 * enable anything at the encoder level. To ensure that runtime PM handling
723 * (using either DPMS or the new "ACTIVE" property) works
724 * @enable must be the inverse of @disable for atomic drivers.
726 void (*enable)(struct drm_encoder *encoder);
731 * This callback is used to validate encoder state for atomic drivers.
732 * Since the encoder is the object connecting the CRTC and connector it
733 * gets passed both states, to be able to validate interactions and
734 * update the CRTC to match what the encoder needs for the requested
737 * Since this provides a strict superset of the functionality of
738 * @mode_fixup (the requested and adjusted modes are both available
739 * through the passed in &struct drm_crtc_state) @mode_fixup is not
740 * called when @atomic_check is implemented.
742 * This function is used by the atomic helpers, but it is optional.
746 * This function is called in the check phase of an atomic update. The
747 * driver is not allowed to change anything outside of the free-standing
748 * state objects passed-in or assembled in the overall &drm_atomic_state
749 * update tracking structure.
751 * Also beware that userspace can request its own custom modes, neither
752 * core nor helpers filter modes to the list of probe modes reported by
753 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
754 * that modes are filtered consistently put any encoder constraints and
755 * limits checks into @mode_valid.
759 * 0 on success, -EINVAL if the state or the transition can't be
760 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
761 * attempt to obtain another state object ran into a &drm_modeset_lock
764 int (*atomic_check)(struct drm_encoder *encoder,
765 struct drm_crtc_state *crtc_state,
766 struct drm_connector_state *conn_state);
770 * drm_encoder_helper_add - sets the helper vtable for an encoder
771 * @encoder: DRM encoder
772 * @funcs: helper vtable to set for @encoder
774 static inline void drm_encoder_helper_add(struct drm_encoder *encoder,
775 const struct drm_encoder_helper_funcs *funcs)
777 encoder->helper_private = funcs;
781 * struct drm_connector_helper_funcs - helper operations for connectors
783 * These functions are used by the atomic and legacy modeset helpers and by the
786 struct drm_connector_helper_funcs {
790 * This function should fill in all modes currently valid for the sink
791 * into the &drm_connector.probed_modes list. It should also update the
792 * EDID property by calling drm_connector_update_edid_property().
794 * The usual way to implement this is to cache the EDID retrieved in the
795 * probe callback somewhere in the driver-private connector structure.
796 * In this function drivers then parse the modes in the EDID and add
797 * them by calling drm_add_edid_modes(). But connectors that driver a
798 * fixed panel can also manually add specific modes using
799 * drm_mode_probed_add(). Drivers which manually add modes should also
800 * make sure that the &drm_connector.display_info,
801 * &drm_connector.width_mm and &drm_connector.height_mm fields are
804 * Virtual drivers that just want some standard VESA mode with a given
805 * resolution can call drm_add_modes_noedid(), and mark the preferred
806 * one using drm_set_preferred_mode().
808 * This function is only called after the @detect hook has indicated
809 * that a sink is connected and when the EDID isn't overridden through
810 * sysfs or the kernel commandline.
812 * This callback is used by the probe helpers in e.g.
813 * drm_helper_probe_single_connector_modes().
815 * To avoid races with concurrent connector state updates, the helper
816 * libraries always call this with the &drm_mode_config.connection_mutex
817 * held. Because of this it's safe to inspect &drm_connector->state.
821 * The number of modes added by calling drm_mode_probed_add().
823 int (*get_modes)(struct drm_connector *connector);
828 * Check to see if anything is attached to the connector. The parameter
829 * force is set to false whilst polling, true when checking the
830 * connector due to a user request. force can be used by the driver to
831 * avoid expensive, destructive operations during automated probing.
833 * This callback is optional, if not implemented the connector will be
834 * considered as always being attached.
836 * This is the atomic version of &drm_connector_funcs.detect.
838 * To avoid races against concurrent connector state updates, the
839 * helper libraries always call this with ctx set to a valid context,
840 * and &drm_mode_config.connection_mutex will always be locked with
841 * the ctx parameter set to this ctx. This allows taking additional
846 * &drm_connector_status indicating the connector's status,
847 * or the error code returned by drm_modeset_lock(), -EDEADLK.
849 int (*detect_ctx)(struct drm_connector *connector,
850 struct drm_modeset_acquire_ctx *ctx,
856 * Callback to validate a mode for a connector, irrespective of the
857 * specific display configuration.
859 * This callback is used by the probe helpers to filter the mode list
860 * (which is usually derived from the EDID data block from the sink).
861 * See e.g. drm_helper_probe_single_connector_modes().
863 * This function is optional.
867 * This only filters the mode list supplied to userspace in the
868 * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid,
869 * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid,
870 * which are also called by the atomic helpers from
871 * drm_atomic_helper_check_modeset(). This allows userspace to force and
872 * ignore sink constraint (like the pixel clock limits in the screen's
873 * EDID), which is useful for e.g. testing, or working around a broken
874 * EDID. Any source hardware constraint (which always need to be
875 * enforced) therefore should be checked in one of the above callbacks,
876 * and not this one here.
878 * To avoid races with concurrent connector state updates, the helper
879 * libraries always call this with the &drm_mode_config.connection_mutex
880 * held. Because of this it's safe to inspect &drm_connector->state.
884 * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum
887 enum drm_mode_status (*mode_valid)(struct drm_connector *connector,
888 struct drm_display_mode *mode);
892 * This function should select the best encoder for the given connector.
894 * This function is used by both the atomic helpers (in the
895 * drm_atomic_helper_check_modeset() function) and in the legacy CRTC
900 * In atomic drivers this function is called in the check phase of an
901 * atomic update. The driver is not allowed to change or inspect
902 * anything outside of arguments passed-in. Atomic drivers which need to
903 * inspect dynamic configuration state should instead use
904 * @atomic_best_encoder.
906 * You can leave this function to NULL if the connector is only
907 * attached to a single encoder and you are using the atomic helpers.
908 * In this case, the core will call drm_atomic_helper_best_encoder()
913 * Encoder that should be used for the given connector and connector
914 * state, or NULL if no suitable encoder exists. Note that the helpers
915 * will ensure that encoders aren't used twice, drivers should not check
918 struct drm_encoder *(*best_encoder)(struct drm_connector *connector);
921 * @atomic_best_encoder:
923 * This is the atomic version of @best_encoder for atomic drivers which
924 * need to select the best encoder depending upon the desired
925 * configuration and can't select it statically.
927 * This function is used by drm_atomic_helper_check_modeset().
928 * If it is not implemented, the core will fallback to @best_encoder
929 * (or drm_atomic_helper_best_encoder() if @best_encoder is NULL).
933 * This function is called in the check phase of an atomic update. The
934 * driver is not allowed to change anything outside of the free-standing
935 * state objects passed-in or assembled in the overall &drm_atomic_state
936 * update tracking structure.
940 * Encoder that should be used for the given connector and connector
941 * state, or NULL if no suitable encoder exists. Note that the helpers
942 * will ensure that encoders aren't used twice, drivers should not check
945 struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector,
946 struct drm_connector_state *connector_state);
951 * This hook is used to validate connector state. This function is
952 * called from &drm_atomic_helper_check_modeset, and is called when
953 * a connector property is set, or a modeset on the crtc is forced.
955 * Because &drm_atomic_helper_check_modeset may be called multiple times,
956 * this function should handle being called multiple times as well.
958 * This function is also allowed to inspect any other object's state and
959 * can add more state objects to the atomic commit if needed. Care must
960 * be taken though to ensure that state check and compute functions for
961 * these added states are all called, and derived state in other objects
962 * all updated. Again the recommendation is to just call check helpers
963 * until a maximal configuration is reached.
967 * This function is called in the check phase of an atomic update. The
968 * driver is not allowed to change anything outside of the free-standing
969 * state objects passed-in or assembled in the overall &drm_atomic_state
970 * update tracking structure.
974 * 0 on success, -EINVAL if the state or the transition can't be
975 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
976 * attempt to obtain another state object ran into a &drm_modeset_lock
979 int (*atomic_check)(struct drm_connector *connector,
980 struct drm_connector_state *state);
985 * This hook is to be used by drivers implementing writeback connectors
986 * that need a point when to commit the writeback job to the hardware.
987 * The writeback_job to commit is available in
988 * &drm_connector_state.writeback_job.
990 * This hook is optional.
992 * This callback is used by the atomic modeset helpers.
994 void (*atomic_commit)(struct drm_connector *connector,
995 struct drm_connector_state *state);
999 * drm_connector_helper_add - sets the helper vtable for a connector
1000 * @connector: DRM connector
1001 * @funcs: helper vtable to set for @connector
1003 static inline void drm_connector_helper_add(struct drm_connector *connector,
1004 const struct drm_connector_helper_funcs *funcs)
1006 connector->helper_private = funcs;
1010 * struct drm_plane_helper_funcs - helper operations for planes
1012 * These functions are used by the atomic helpers and by the transitional plane
1015 struct drm_plane_helper_funcs {
1019 * This hook is to prepare a framebuffer for scanout by e.g. pinning
1020 * its backing storage or relocating it into a contiguous block of
1021 * VRAM. Other possible preparatory work includes flushing caches.
1023 * This function must not block for outstanding rendering, since it is
1024 * called in the context of the atomic IOCTL even for async commits to
1025 * be able to return any errors to userspace. Instead the recommended
1026 * way is to fill out the &drm_plane_state.fence of the passed-in
1027 * &drm_plane_state. If the driver doesn't support native fences then
1028 * equivalent functionality should be implemented through private
1029 * members in the plane structure.
1031 * Drivers which always have their buffers pinned should use
1032 * drm_gem_fb_prepare_fb() for this hook.
1034 * The helpers will call @cleanup_fb with matching arguments for every
1035 * successful call to this hook.
1037 * This callback is used by the atomic modeset helpers and by the
1038 * transitional plane helpers, but it is optional.
1042 * 0 on success or one of the following negative error codes allowed by
1043 * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers
1044 * this callback is the only one which can fail an atomic commit,
1045 * everything else must complete successfully.
1047 int (*prepare_fb)(struct drm_plane *plane,
1048 struct drm_plane_state *new_state);
1052 * This hook is called to clean up any resources allocated for the given
1053 * framebuffer and plane configuration in @prepare_fb.
1055 * This callback is used by the atomic modeset helpers and by the
1056 * transitional plane helpers, but it is optional.
1058 void (*cleanup_fb)(struct drm_plane *plane,
1059 struct drm_plane_state *old_state);
1064 * Drivers should check plane specific constraints in this hook.
1066 * When using drm_atomic_helper_check_planes() plane's @atomic_check
1067 * hooks are called before the ones for CRTCs, which allows drivers to
1068 * request shared resources that the CRTC controls here. For more
1069 * complicated dependencies the driver can call the provided check helpers
1070 * multiple times until the computed state has a final configuration and
1071 * everything has been checked.
1073 * This function is also allowed to inspect any other object's state and
1074 * can add more state objects to the atomic commit if needed. Care must
1075 * be taken though to ensure that state check and compute functions for
1076 * these added states are all called, and derived state in other objects
1077 * all updated. Again the recommendation is to just call check helpers
1078 * until a maximal configuration is reached.
1080 * This callback is used by the atomic modeset helpers and by the
1081 * transitional plane helpers, but it is optional.
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.
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
1097 int (*atomic_check)(struct drm_plane *plane,
1098 struct drm_plane_state *state);
1103 * Drivers should use this function to update the plane state. This
1104 * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and
1105 * drm_crtc_helper_funcs.atomic_flush callbacks.
1107 * Note that the power state of the display pipe when this function is
1108 * called depends upon the exact helpers and calling sequence the driver
1109 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
1110 * the tradeoffs and variants of plane commit helpers.
1112 * This callback is used by the atomic modeset helpers and by the
1113 * transitional plane helpers, but it is optional.
1115 void (*atomic_update)(struct drm_plane *plane,
1116 struct drm_plane_state *old_state);
1120 * Drivers should use this function to unconditionally disable a plane.
1121 * This hook is called in-between the
1122 * &drm_crtc_helper_funcs.atomic_begin and
1123 * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to
1124 * @atomic_update, which will be called for disabling planes, too, if
1125 * the @atomic_disable hook isn't implemented.
1127 * This hook is also useful to disable planes in preparation of a modeset,
1128 * by calling drm_atomic_helper_disable_planes_on_crtc() from the
1129 * &drm_crtc_helper_funcs.disable hook.
1131 * Note that the power state of the display pipe when this function is
1132 * called depends upon the exact helpers and calling sequence the driver
1133 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
1134 * the tradeoffs and variants of plane commit helpers.
1136 * This callback is used by the atomic modeset helpers and by the
1137 * transitional plane helpers, but it is optional.
1139 void (*atomic_disable)(struct drm_plane *plane,
1140 struct drm_plane_state *old_state);
1143 * @atomic_async_check:
1145 * Drivers should set this function pointer to check if the plane state
1146 * can be updated in a async fashion. Here async means "not vblank
1149 * This hook is called by drm_atomic_async_check() to establish if a
1150 * given update can be committed asynchronously, that is, if it can
1151 * jump ahead of the state currently queued for update.
1155 * Return 0 on success and any error returned indicates that the update
1156 * can not be applied in asynchronous manner.
1158 int (*atomic_async_check)(struct drm_plane *plane,
1159 struct drm_plane_state *state);
1162 * @atomic_async_update:
1164 * Drivers should set this function pointer to perform asynchronous
1165 * updates of planes, that is, jump ahead of the currently queued
1166 * state and update the plane. Here async means "not vblank
1169 * This hook is called by drm_atomic_helper_async_commit().
1171 * An async update will happen on legacy cursor updates. An async
1172 * update won't happen if there is an outstanding commit modifying
1175 * Note that unlike &drm_plane_helper_funcs.atomic_update this hook
1176 * takes the new &drm_plane_state as parameter. When doing async_update
1177 * drivers shouldn't replace the &drm_plane_state but update the
1178 * current one with the new plane configurations in the new
1182 * - It only works for single plane updates
1183 * - Async Pageflips are not supported yet
1184 * - Some hw might still scan out the old buffer until the next
1185 * vblank, however we let go of the fb references as soon as
1186 * we run this hook. For now drivers must implement their own workers
1187 * for deferring if needed, until a common solution is created.
1189 void (*atomic_async_update)(struct drm_plane *plane,
1190 struct drm_plane_state *new_state);
1194 * drm_plane_helper_add - sets the helper vtable for a plane
1196 * @funcs: helper vtable to set for @plane
1198 static inline void drm_plane_helper_add(struct drm_plane *plane,
1199 const struct drm_plane_helper_funcs *funcs)
1201 plane->helper_private = funcs;
1205 * struct drm_mode_config_helper_funcs - global modeset helper operations
1207 * These helper functions are used by the atomic helpers.
1209 struct drm_mode_config_helper_funcs {
1211 * @atomic_commit_tail:
1213 * This hook is used by the default atomic_commit() hook implemented in
1214 * drm_atomic_helper_commit() together with the nonblocking commit
1215 * helpers (see drm_atomic_helper_setup_commit() for a starting point)
1216 * to implement blocking and nonblocking commits easily. It is not used
1217 * by the atomic helpers
1219 * This function is called when the new atomic state has already been
1220 * swapped into the various state pointers. The passed in state
1221 * therefore contains copies of the old/previous state. This hook should
1222 * commit the new state into hardware. Note that the helpers have
1223 * already waited for preceeding atomic commits and fences, but drivers
1224 * can add more waiting calls at the start of their implementation, e.g.
1225 * to wait for driver-internal request for implicit syncing, before
1226 * starting to commit the update to the hardware.
1228 * After the atomic update is committed to the hardware this hook needs
1229 * to call drm_atomic_helper_commit_hw_done(). Then wait for the upate
1230 * to be executed by the hardware, for example using
1231 * drm_atomic_helper_wait_for_vblanks() or
1232 * drm_atomic_helper_wait_for_flip_done(), and then clean up the old
1233 * framebuffers using drm_atomic_helper_cleanup_planes().
1235 * When disabling a CRTC this hook _must_ stall for the commit to
1236 * complete. Vblank waits don't work on disabled CRTC, hence the core
1237 * can't take care of this. And it also can't rely on the vblank event,
1238 * since that can be signalled already when the screen shows black,
1239 * which can happen much earlier than the last hardware access needed to
1240 * shut off the display pipeline completely.
1242 * This hook is optional, the default implementation is
1243 * drm_atomic_helper_commit_tail().
1245 void (*atomic_commit_tail)(struct drm_atomic_state *state);