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 objects passed-in or assembled in the overall &drm_atomic_state 340 * update tracking structure. 341 * 342 * Also beware that userspace can request its own custom modes, neither 343 * core nor helpers filter modes to the list of probe modes reported by 344 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 345 * that modes are filtered consistently put any CRTC constraints and 346 * limits checks into @mode_valid. 347 * 348 * RETURNS: 349 * 350 * 0 on success, -EINVAL if the state or the transition can't be 351 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 352 * attempt to obtain another state object ran into a &drm_modeset_lock 353 * deadlock. 354 */ 355 int (*atomic_check)(struct drm_crtc *crtc, 356 struct drm_crtc_state *state); 357 358 /** 359 * @atomic_begin: 360 * 361 * Drivers should prepare for an atomic update of multiple planes on 362 * a CRTC in this hook. Depending upon hardware this might be vblank 363 * evasion, blocking updates by setting bits or doing preparatory work 364 * for e.g. manual update display. 365 * 366 * This hook is called before any plane commit functions are called. 367 * 368 * Note that the power state of the display pipe when this function is 369 * called depends upon the exact helpers and calling sequence the driver 370 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 371 * the tradeoffs and variants of plane commit helpers. 372 * 373 * This callback is used by the atomic modeset helpers and by the 374 * transitional plane helpers, but it is optional. 375 */ 376 void (*atomic_begin)(struct drm_crtc *crtc, 377 struct drm_crtc_state *old_crtc_state); 378 /** 379 * @atomic_flush: 380 * 381 * Drivers should finalize an atomic update of multiple planes on 382 * a CRTC in this hook. Depending upon hardware this might include 383 * checking that vblank evasion was successful, unblocking updates by 384 * setting bits or setting the GO bit to flush out all updates. 385 * 386 * Simple hardware or hardware with special requirements can commit and 387 * flush out all updates for all planes from this hook and forgo all the 388 * other commit hooks for plane updates. 389 * 390 * This hook is called after any plane commit functions are called. 391 * 392 * Note that the power state of the display pipe when this function is 393 * called depends upon the exact helpers and calling sequence the driver 394 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 395 * the tradeoffs and variants of plane commit helpers. 396 * 397 * This callback is used by the atomic modeset helpers and by the 398 * transitional plane helpers, but it is optional. 399 */ 400 void (*atomic_flush)(struct drm_crtc *crtc, 401 struct drm_crtc_state *old_crtc_state); 402 403 /** 404 * @atomic_enable: 405 * 406 * This callback should be used to enable the CRTC. With the atomic 407 * drivers it is called before all encoders connected to this CRTC are 408 * enabled through the encoder's own &drm_encoder_helper_funcs.enable 409 * hook. If that sequence is too simple drivers can just add their own 410 * hooks and call it from this CRTC callback here by looping over all 411 * encoders connected to it using for_each_encoder_on_crtc(). 412 * 413 * This hook is used only by atomic helpers, for symmetry with 414 * @atomic_disable. Atomic drivers don't need to implement it if there's 415 * no need to enable anything at the CRTC level. To ensure that runtime 416 * PM handling (using either DPMS or the new "ACTIVE" property) works 417 * @atomic_enable must be the inverse of @atomic_disable for atomic 418 * drivers. 419 * 420 * Drivers can use the @old_crtc_state input parameter if the operations 421 * needed to enable the CRTC don't depend solely on the new state but 422 * also on the transition between the old state and the new state. 423 * 424 * This function is optional. 425 */ 426 void (*atomic_enable)(struct drm_crtc *crtc, 427 struct drm_crtc_state *old_crtc_state); 428 429 /** 430 * @atomic_disable: 431 * 432 * This callback should be used to disable the CRTC. With the atomic 433 * drivers it is called after all encoders connected to this CRTC have 434 * been shut off already using their own 435 * &drm_encoder_helper_funcs.disable hook. If that sequence is too 436 * simple drivers can just add their own hooks and call it from this 437 * CRTC callback here by looping over all encoders connected to it using 438 * for_each_encoder_on_crtc(). 439 * 440 * This hook is used only by atomic helpers. Atomic drivers don't 441 * need to implement it if there's no need to disable anything at the 442 * CRTC level. 443 * 444 * Comparing to @disable, this one provides the additional input 445 * parameter @old_crtc_state which could be used to access the old 446 * state. Atomic drivers should consider to use this one instead 447 * of @disable. 448 * 449 * This function is optional. 450 */ 451 void (*atomic_disable)(struct drm_crtc *crtc, 452 struct drm_crtc_state *old_crtc_state); 453 }; 454 455 /** 456 * drm_crtc_helper_add - sets the helper vtable for a crtc 457 * @crtc: DRM CRTC 458 * @funcs: helper vtable to set for @crtc 459 */ 460 static inline void drm_crtc_helper_add(struct drm_crtc *crtc, 461 const struct drm_crtc_helper_funcs *funcs) 462 { 463 crtc->helper_private = funcs; 464 } 465 466 /** 467 * struct drm_encoder_helper_funcs - helper operations for encoders 468 * 469 * These hooks are used by the legacy CRTC helpers, the transitional plane 470 * helpers and the new atomic modesetting helpers. 471 */ 472 struct drm_encoder_helper_funcs { 473 /** 474 * @dpms: 475 * 476 * Callback to control power levels on the encoder. If the mode passed in 477 * is unsupported, the provider must use the next lowest power level. 478 * This is used by the legacy encoder helpers to implement DPMS 479 * functionality in drm_helper_connector_dpms(). 480 * 481 * This callback is also used to disable an encoder by calling it with 482 * DRM_MODE_DPMS_OFF if the @disable hook isn't used. 483 * 484 * This callback is used by the legacy CRTC helpers. Atomic helpers 485 * also support using this hook for enabling and disabling an encoder to 486 * facilitate transitions to atomic, but it is deprecated. Instead 487 * @enable and @disable should be used. 488 */ 489 void (*dpms)(struct drm_encoder *encoder, int mode); 490 491 /** 492 * @mode_valid: 493 * 494 * This callback is used to check if a specific mode is valid in this 495 * encoder. This should be implemented if the encoder has some sort 496 * of restriction in the modes it can display. For example, a given 497 * encoder may be responsible to set a clock value. If the clock can 498 * not produce all the values for the available modes then this callback 499 * can be used to restrict the number of modes to only the ones that 500 * can be displayed. 501 * 502 * This hook is used by the probe helpers to filter the mode list in 503 * drm_helper_probe_single_connector_modes(), and it is used by the 504 * atomic helpers to validate modes supplied by userspace in 505 * drm_atomic_helper_check_modeset(). 506 * 507 * This function is optional. 508 * 509 * NOTE: 510 * 511 * Since this function is both called from the check phase of an atomic 512 * commit, and the mode validation in the probe paths it is not allowed 513 * to look at anything else but the passed-in mode, and validate it 514 * against configuration-invariant hardward constraints. Any further 515 * limits which depend upon the configuration can only be checked in 516 * @mode_fixup or @atomic_check. 517 * 518 * RETURNS: 519 * 520 * drm_mode_status Enum 521 */ 522 enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc, 523 const struct drm_display_mode *mode); 524 525 /** 526 * @mode_fixup: 527 * 528 * This callback is used to validate and adjust a mode. The parameter 529 * mode is the display mode that should be fed to the next element in 530 * the display chain, either the final &drm_connector or a &drm_bridge. 531 * The parameter adjusted_mode is the input mode the encoder requires. It 532 * can be modified by this callback and does not need to match mode. See 533 * also &drm_crtc_state.adjusted_mode for more details. 534 * 535 * This function is used by both legacy CRTC helpers and atomic helpers. 536 * This hook is optional. 537 * 538 * NOTE: 539 * 540 * This function is called in the check phase of atomic modesets, which 541 * can be aborted for any reason (including on userspace's request to 542 * just check whether a configuration would be possible). Atomic drivers 543 * MUST NOT touch any persistent state (hardware or software) or data 544 * structures except the passed in adjusted_mode parameter. 545 * 546 * This is in contrast to the legacy CRTC helpers where this was 547 * allowed. 548 * 549 * Atomic drivers which need to inspect and adjust more state should 550 * instead use the @atomic_check callback. If @atomic_check is used, 551 * this hook isn't called since @atomic_check allows a strict superset 552 * of the functionality of @mode_fixup. 553 * 554 * Also beware that userspace can request its own custom modes, neither 555 * core nor helpers filter modes to the list of probe modes reported by 556 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 557 * that modes are filtered consistently put any encoder constraints and 558 * limits checks into @mode_valid. 559 * 560 * RETURNS: 561 * 562 * True if an acceptable configuration is possible, false if the modeset 563 * operation should be rejected. 564 */ 565 bool (*mode_fixup)(struct drm_encoder *encoder, 566 const struct drm_display_mode *mode, 567 struct drm_display_mode *adjusted_mode); 568 569 /** 570 * @prepare: 571 * 572 * This callback should prepare the encoder for a subsequent modeset, 573 * which in practice means the driver should disable the encoder if it 574 * is running. Most drivers ended up implementing this by calling their 575 * @dpms hook with DRM_MODE_DPMS_OFF. 576 * 577 * This callback is used by the legacy CRTC helpers. Atomic helpers 578 * also support using this hook for disabling an encoder to facilitate 579 * transitions to atomic, but it is deprecated. Instead @disable should 580 * be used. 581 */ 582 void (*prepare)(struct drm_encoder *encoder); 583 584 /** 585 * @commit: 586 * 587 * This callback should commit the new mode on the encoder after a modeset, 588 * which in practice means the driver should enable the encoder. Most 589 * drivers ended up implementing this by calling their @dpms hook with 590 * DRM_MODE_DPMS_ON. 591 * 592 * This callback is used by the legacy CRTC helpers. Atomic helpers 593 * also support using this hook for enabling an encoder to facilitate 594 * transitions to atomic, but it is deprecated. Instead @enable should 595 * be used. 596 */ 597 void (*commit)(struct drm_encoder *encoder); 598 599 /** 600 * @mode_set: 601 * 602 * This callback is used to update the display mode of an encoder. 603 * 604 * Note that the display pipe is completely off when this function is 605 * called. Drivers which need hardware to be running before they program 606 * the new display mode (because they implement runtime PM) should not 607 * use this hook, because the helper library calls it only once and not 608 * every time the display pipeline is suspend using either DPMS or the 609 * new "ACTIVE" property. Such drivers should instead move all their 610 * encoder setup into the @enable callback. 611 * 612 * This callback is used both by the legacy CRTC helpers and the atomic 613 * modeset helpers. It is optional in the atomic helpers. 614 * 615 * NOTE: 616 * 617 * If the driver uses the atomic modeset helpers and needs to inspect 618 * the connector state or connector display info during mode setting, 619 * @atomic_mode_set can be used instead. 620 */ 621 void (*mode_set)(struct drm_encoder *encoder, 622 struct drm_display_mode *mode, 623 struct drm_display_mode *adjusted_mode); 624 625 /** 626 * @atomic_mode_set: 627 * 628 * This callback is used to update the display mode of an encoder. 629 * 630 * Note that the display pipe is completely off when this function is 631 * called. Drivers which need hardware to be running before they program 632 * the new display mode (because they implement runtime PM) should not 633 * use this hook, because the helper library calls it only once and not 634 * every time the display pipeline is suspended using either DPMS or the 635 * new "ACTIVE" property. Such drivers should instead move all their 636 * encoder setup into the @enable callback. 637 * 638 * This callback is used by the atomic modeset helpers in place of the 639 * @mode_set callback, if set by the driver. It is optional and should 640 * be used instead of @mode_set if the driver needs to inspect the 641 * connector state or display info, since there is no direct way to 642 * go from the encoder to the current connector. 643 */ 644 void (*atomic_mode_set)(struct drm_encoder *encoder, 645 struct drm_crtc_state *crtc_state, 646 struct drm_connector_state *conn_state); 647 648 /** 649 * @get_crtc: 650 * 651 * This callback is used by the legacy CRTC helpers to work around 652 * deficiencies in its own book-keeping. 653 * 654 * Do not use, use atomic helpers instead, which get the book keeping 655 * right. 656 * 657 * FIXME: 658 * 659 * Currently only nouveau is using this, and as soon as nouveau is 660 * atomic we can ditch this hook. 661 */ 662 struct drm_crtc *(*get_crtc)(struct drm_encoder *encoder); 663 664 /** 665 * @detect: 666 * 667 * This callback can be used by drivers who want to do detection on the 668 * encoder object instead of in connector functions. 669 * 670 * It is not used by any helper and therefore has purely driver-specific 671 * semantics. New drivers shouldn't use this and instead just implement 672 * their own private callbacks. 673 * 674 * FIXME: 675 * 676 * This should just be converted into a pile of driver vfuncs. 677 * Currently radeon, amdgpu and nouveau are using it. 678 */ 679 enum drm_connector_status (*detect)(struct drm_encoder *encoder, 680 struct drm_connector *connector); 681 682 /** 683 * @disable: 684 * 685 * This callback should be used to disable the encoder. With the atomic 686 * drivers it is called before this encoder's CRTC has been shut off 687 * using their own &drm_crtc_helper_funcs.disable hook. If that 688 * sequence is too simple drivers can just add their own driver private 689 * encoder hooks and call them from CRTC's callback by looping over all 690 * encoders connected to it using for_each_encoder_on_crtc(). 691 * 692 * This hook is used both by legacy CRTC helpers and atomic helpers. 693 * Atomic drivers don't need to implement it if there's no need to 694 * disable anything at the encoder level. To ensure that runtime PM 695 * handling (using either DPMS or the new "ACTIVE" property) works 696 * @disable must be the inverse of @enable for atomic drivers. 697 * 698 * NOTE: 699 * 700 * With legacy CRTC helpers there's a big semantic difference between 701 * @disable and other hooks (like @prepare or @dpms) used to shut down a 702 * encoder: @disable is only called when also logically disabling the 703 * display pipeline and needs to release any resources acquired in 704 * @mode_set (like shared PLLs, or again release pinned framebuffers). 705 * 706 * Therefore @disable must be the inverse of @mode_set plus @commit for 707 * drivers still using legacy CRTC helpers, which is different from the 708 * rules under atomic. 709 */ 710 void (*disable)(struct drm_encoder *encoder); 711 712 /** 713 * @enable: 714 * 715 * This callback should be used to enable the encoder. With the atomic 716 * drivers it is called after this encoder's CRTC has been enabled using 717 * their own &drm_crtc_helper_funcs.enable hook. If that sequence is 718 * too simple drivers can just add their own driver private encoder 719 * hooks and call them from CRTC's callback by looping over all encoders 720 * connected to it using for_each_encoder_on_crtc(). 721 * 722 * This hook is used only by atomic helpers, for symmetry with @disable. 723 * Atomic drivers don't need to implement it if there's no need to 724 * enable anything at the encoder level. To ensure that runtime PM handling 725 * (using either DPMS or the new "ACTIVE" property) works 726 * @enable must be the inverse of @disable for atomic drivers. 727 */ 728 void (*enable)(struct drm_encoder *encoder); 729 730 /** 731 * @atomic_check: 732 * 733 * This callback is used to validate encoder state for atomic drivers. 734 * Since the encoder is the object connecting the CRTC and connector it 735 * gets passed both states, to be able to validate interactions and 736 * update the CRTC to match what the encoder needs for the requested 737 * connector. 738 * 739 * Since this provides a strict superset of the functionality of 740 * @mode_fixup (the requested and adjusted modes are both available 741 * through the passed in &struct drm_crtc_state) @mode_fixup is not 742 * called when @atomic_check is implemented. 743 * 744 * This function is used by the atomic helpers, but it is optional. 745 * 746 * NOTE: 747 * 748 * This function is called in the check phase of an atomic update. The 749 * driver is not allowed to change anything outside of the free-standing 750 * state objects passed-in or assembled in the overall &drm_atomic_state 751 * update tracking structure. 752 * 753 * Also beware that userspace can request its own custom modes, neither 754 * core nor helpers filter modes to the list of probe modes reported by 755 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 756 * that modes are filtered consistently put any encoder constraints and 757 * limits checks into @mode_valid. 758 * 759 * RETURNS: 760 * 761 * 0 on success, -EINVAL if the state or the transition can't be 762 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 763 * attempt to obtain another state object ran into a &drm_modeset_lock 764 * deadlock. 765 */ 766 int (*atomic_check)(struct drm_encoder *encoder, 767 struct drm_crtc_state *crtc_state, 768 struct drm_connector_state *conn_state); 769 }; 770 771 /** 772 * drm_encoder_helper_add - sets the helper vtable for an encoder 773 * @encoder: DRM encoder 774 * @funcs: helper vtable to set for @encoder 775 */ 776 static inline void drm_encoder_helper_add(struct drm_encoder *encoder, 777 const struct drm_encoder_helper_funcs *funcs) 778 { 779 encoder->helper_private = funcs; 780 } 781 782 /** 783 * struct drm_connector_helper_funcs - helper operations for connectors 784 * 785 * These functions are used by the atomic and legacy modeset helpers and by the 786 * probe helpers. 787 */ 788 struct drm_connector_helper_funcs { 789 /** 790 * @get_modes: 791 * 792 * This function should fill in all modes currently valid for the sink 793 * into the &drm_connector.probed_modes list. It should also update the 794 * EDID property by calling drm_connector_update_edid_property(). 795 * 796 * The usual way to implement this is to cache the EDID retrieved in the 797 * probe callback somewhere in the driver-private connector structure. 798 * In this function drivers then parse the modes in the EDID and add 799 * them by calling drm_add_edid_modes(). But connectors that driver a 800 * fixed panel can also manually add specific modes using 801 * drm_mode_probed_add(). Drivers which manually add modes should also 802 * make sure that the &drm_connector.display_info, 803 * &drm_connector.width_mm and &drm_connector.height_mm fields are 804 * filled in. 805 * 806 * Virtual drivers that just want some standard VESA mode with a given 807 * resolution can call drm_add_modes_noedid(), and mark the preferred 808 * one using drm_set_preferred_mode(). 809 * 810 * This function is only called after the @detect hook has indicated 811 * that a sink is connected and when the EDID isn't overridden through 812 * sysfs or the kernel commandline. 813 * 814 * This callback is used by the probe helpers in e.g. 815 * drm_helper_probe_single_connector_modes(). 816 * 817 * To avoid races with concurrent connector state updates, the helper 818 * libraries always call this with the &drm_mode_config.connection_mutex 819 * held. Because of this it's safe to inspect &drm_connector->state. 820 * 821 * RETURNS: 822 * 823 * The number of modes added by calling drm_mode_probed_add(). 824 */ 825 int (*get_modes)(struct drm_connector *connector); 826 827 /** 828 * @detect_ctx: 829 * 830 * Check to see if anything is attached to the connector. The parameter 831 * force is set to false whilst polling, true when checking the 832 * connector due to a user request. force can be used by the driver to 833 * avoid expensive, destructive operations during automated probing. 834 * 835 * This callback is optional, if not implemented the connector will be 836 * considered as always being attached. 837 * 838 * This is the atomic version of &drm_connector_funcs.detect. 839 * 840 * To avoid races against concurrent connector state updates, the 841 * helper libraries always call this with ctx set to a valid context, 842 * and &drm_mode_config.connection_mutex will always be locked with 843 * the ctx parameter set to this ctx. This allows taking additional 844 * locks as required. 845 * 846 * RETURNS: 847 * 848 * &drm_connector_status indicating the connector's status, 849 * or the error code returned by drm_modeset_lock(), -EDEADLK. 850 */ 851 int (*detect_ctx)(struct drm_connector *connector, 852 struct drm_modeset_acquire_ctx *ctx, 853 bool force); 854 855 /** 856 * @mode_valid: 857 * 858 * Callback to validate a mode for a connector, irrespective of the 859 * specific display configuration. 860 * 861 * This callback is used by the probe helpers to filter the mode list 862 * (which is usually derived from the EDID data block from the sink). 863 * See e.g. drm_helper_probe_single_connector_modes(). 864 * 865 * This function is optional. 866 * 867 * NOTE: 868 * 869 * This only filters the mode list supplied to userspace in the 870 * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid, 871 * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid, 872 * which are also called by the atomic helpers from 873 * drm_atomic_helper_check_modeset(). This allows userspace to force and 874 * ignore sink constraint (like the pixel clock limits in the screen's 875 * EDID), which is useful for e.g. testing, or working around a broken 876 * EDID. Any source hardware constraint (which always need to be 877 * enforced) therefore should be checked in one of the above callbacks, 878 * and not this one here. 879 * 880 * To avoid races with concurrent connector state updates, the helper 881 * libraries always call this with the &drm_mode_config.connection_mutex 882 * held. Because of this it's safe to inspect &drm_connector->state. 883 * 884 * RETURNS: 885 * 886 * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum 887 * drm_mode_status. 888 */ 889 enum drm_mode_status (*mode_valid)(struct drm_connector *connector, 890 struct drm_display_mode *mode); 891 /** 892 * @best_encoder: 893 * 894 * This function should select the best encoder for the given connector. 895 * 896 * This function is used by both the atomic helpers (in the 897 * drm_atomic_helper_check_modeset() function) and in the legacy CRTC 898 * helpers. 899 * 900 * NOTE: 901 * 902 * In atomic drivers this function is called in the check phase of an 903 * atomic update. The driver is not allowed to change or inspect 904 * anything outside of arguments passed-in. Atomic drivers which need to 905 * inspect dynamic configuration state should instead use 906 * @atomic_best_encoder. 907 * 908 * You can leave this function to NULL if the connector is only 909 * attached to a single encoder and you are using the atomic helpers. 910 * In this case, the core will call drm_atomic_helper_best_encoder() 911 * for you. 912 * 913 * RETURNS: 914 * 915 * Encoder that should be used for the given connector and connector 916 * state, or NULL if no suitable encoder exists. Note that the helpers 917 * will ensure that encoders aren't used twice, drivers should not check 918 * for this. 919 */ 920 struct drm_encoder *(*best_encoder)(struct drm_connector *connector); 921 922 /** 923 * @atomic_best_encoder: 924 * 925 * This is the atomic version of @best_encoder for atomic drivers which 926 * need to select the best encoder depending upon the desired 927 * configuration and can't select it statically. 928 * 929 * This function is used by drm_atomic_helper_check_modeset(). 930 * If it is not implemented, the core will fallback to @best_encoder 931 * (or drm_atomic_helper_best_encoder() if @best_encoder is NULL). 932 * 933 * NOTE: 934 * 935 * This function is called in the check phase of an atomic update. The 936 * driver is not allowed to change anything outside of the free-standing 937 * state objects passed-in or assembled in the overall &drm_atomic_state 938 * update tracking structure. 939 * 940 * RETURNS: 941 * 942 * Encoder that should be used for the given connector and connector 943 * state, or NULL if no suitable encoder exists. Note that the helpers 944 * will ensure that encoders aren't used twice, drivers should not check 945 * for this. 946 */ 947 struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector, 948 struct drm_connector_state *connector_state); 949 950 /** 951 * @atomic_check: 952 * 953 * This hook is used to validate connector state. This function is 954 * called from &drm_atomic_helper_check_modeset, and is called when 955 * a connector property is set, or a modeset on the crtc is forced. 956 * 957 * Because &drm_atomic_helper_check_modeset may be called multiple times, 958 * this function should handle being called multiple times as well. 959 * 960 * This function is also allowed to inspect any other object's state and 961 * can add more state objects to the atomic commit if needed. Care must 962 * be taken though to ensure that state check and compute functions for 963 * these added states are all called, and derived state in other objects 964 * all updated. Again the recommendation is to just call check helpers 965 * until a maximal configuration is reached. 966 * 967 * NOTE: 968 * 969 * This function is called in the check phase of an atomic update. The 970 * driver is not allowed to change anything outside of the free-standing 971 * state objects passed-in or assembled in the overall &drm_atomic_state 972 * update tracking structure. 973 * 974 * RETURNS: 975 * 976 * 0 on success, -EINVAL if the state or the transition can't be 977 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 978 * attempt to obtain another state object ran into a &drm_modeset_lock 979 * deadlock. 980 */ 981 int (*atomic_check)(struct drm_connector *connector, 982 struct drm_connector_state *state); 983 984 /** 985 * @atomic_commit: 986 * 987 * This hook is to be used by drivers implementing writeback connectors 988 * that need a point when to commit the writeback job to the hardware. 989 * The writeback_job to commit is available in 990 * &drm_connector_state.writeback_job. 991 * 992 * This hook is optional. 993 * 994 * This callback is used by the atomic modeset helpers. 995 */ 996 void (*atomic_commit)(struct drm_connector *connector, 997 struct drm_connector_state *state); 998 999 int (*prepare_writeback_job)(struct drm_writeback_connector *connector, 1000 struct drm_writeback_job *job); 1001 void (*cleanup_writeback_job)(struct drm_writeback_connector *connector, 1002 struct drm_writeback_job *job); 1003 }; 1004 1005 /** 1006 * drm_connector_helper_add - sets the helper vtable for a connector 1007 * @connector: DRM connector 1008 * @funcs: helper vtable to set for @connector 1009 */ 1010 static inline void drm_connector_helper_add(struct drm_connector *connector, 1011 const struct drm_connector_helper_funcs *funcs) 1012 { 1013 connector->helper_private = funcs; 1014 } 1015 1016 /** 1017 * struct drm_plane_helper_funcs - helper operations for planes 1018 * 1019 * These functions are used by the atomic helpers and by the transitional plane 1020 * helpers. 1021 */ 1022 struct drm_plane_helper_funcs { 1023 /** 1024 * @prepare_fb: 1025 * 1026 * This hook is to prepare a framebuffer for scanout by e.g. pinning 1027 * its backing storage or relocating it into a contiguous block of 1028 * VRAM. Other possible preparatory work includes flushing caches. 1029 * 1030 * This function must not block for outstanding rendering, since it is 1031 * called in the context of the atomic IOCTL even for async commits to 1032 * be able to return any errors to userspace. Instead the recommended 1033 * way is to fill out the &drm_plane_state.fence of the passed-in 1034 * &drm_plane_state. If the driver doesn't support native fences then 1035 * equivalent functionality should be implemented through private 1036 * members in the plane structure. 1037 * 1038 * Drivers which always have their buffers pinned should use 1039 * drm_gem_fb_prepare_fb() for this hook. 1040 * 1041 * The helpers will call @cleanup_fb with matching arguments for every 1042 * successful call to this hook. 1043 * 1044 * This callback is used by the atomic modeset helpers and by the 1045 * transitional plane helpers, but it is optional. 1046 * 1047 * RETURNS: 1048 * 1049 * 0 on success or one of the following negative error codes allowed by 1050 * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers 1051 * this callback is the only one which can fail an atomic commit, 1052 * everything else must complete successfully. 1053 */ 1054 int (*prepare_fb)(struct drm_plane *plane, 1055 struct drm_plane_state *new_state); 1056 /** 1057 * @cleanup_fb: 1058 * 1059 * This hook is called to clean up any resources allocated for the given 1060 * framebuffer and plane configuration in @prepare_fb. 1061 * 1062 * This callback is used by the atomic modeset helpers and by the 1063 * transitional plane helpers, but it is optional. 1064 */ 1065 void (*cleanup_fb)(struct drm_plane *plane, 1066 struct drm_plane_state *old_state); 1067 1068 /** 1069 * @atomic_check: 1070 * 1071 * Drivers should check plane specific constraints in this hook. 1072 * 1073 * When using drm_atomic_helper_check_planes() plane's @atomic_check 1074 * hooks are called before the ones for CRTCs, which allows drivers to 1075 * request shared resources that the CRTC controls here. For more 1076 * complicated dependencies the driver can call the provided check helpers 1077 * multiple times until the computed state has a final configuration and 1078 * everything has been checked. 1079 * 1080 * This function is also allowed to inspect any other object's state and 1081 * can add more state objects to the atomic commit if needed. Care must 1082 * be taken though to ensure that state check and compute functions for 1083 * these added states are all called, and derived state in other objects 1084 * all updated. Again the recommendation is to just call check helpers 1085 * until a maximal configuration is reached. 1086 * 1087 * This callback is used by the atomic modeset helpers and by the 1088 * transitional plane helpers, but it is optional. 1089 * 1090 * NOTE: 1091 * 1092 * This function is called in the check phase of an atomic update. The 1093 * driver is not allowed to change anything outside of the free-standing 1094 * state objects passed-in or assembled in the overall &drm_atomic_state 1095 * update tracking structure. 1096 * 1097 * RETURNS: 1098 * 1099 * 0 on success, -EINVAL if the state or the transition can't be 1100 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 1101 * attempt to obtain another state object ran into a &drm_modeset_lock 1102 * deadlock. 1103 */ 1104 int (*atomic_check)(struct drm_plane *plane, 1105 struct drm_plane_state *state); 1106 1107 /** 1108 * @atomic_update: 1109 * 1110 * Drivers should use this function to update the plane state. This 1111 * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and 1112 * drm_crtc_helper_funcs.atomic_flush callbacks. 1113 * 1114 * Note that the power state of the display pipe when this function is 1115 * called depends upon the exact helpers and calling sequence the driver 1116 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 1117 * the tradeoffs and variants of plane commit helpers. 1118 * 1119 * This callback is used by the atomic modeset helpers and by the 1120 * transitional plane helpers, but it is optional. 1121 */ 1122 void (*atomic_update)(struct drm_plane *plane, 1123 struct drm_plane_state *old_state); 1124 /** 1125 * @atomic_disable: 1126 * 1127 * Drivers should use this function to unconditionally disable a plane. 1128 * This hook is called in-between the 1129 * &drm_crtc_helper_funcs.atomic_begin and 1130 * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to 1131 * @atomic_update, which will be called for disabling planes, too, if 1132 * the @atomic_disable hook isn't implemented. 1133 * 1134 * This hook is also useful to disable planes in preparation of a modeset, 1135 * by calling drm_atomic_helper_disable_planes_on_crtc() from the 1136 * &drm_crtc_helper_funcs.disable hook. 1137 * 1138 * Note that the power state of the display pipe when this function is 1139 * called depends upon the exact helpers and calling sequence the driver 1140 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 1141 * the tradeoffs and variants of plane commit helpers. 1142 * 1143 * This callback is used by the atomic modeset helpers and by the 1144 * transitional plane helpers, but it is optional. 1145 */ 1146 void (*atomic_disable)(struct drm_plane *plane, 1147 struct drm_plane_state *old_state); 1148 1149 /** 1150 * @atomic_async_check: 1151 * 1152 * Drivers should set this function pointer to check if the plane state 1153 * can be updated in a async fashion. Here async means "not vblank 1154 * synchronized". 1155 * 1156 * This hook is called by drm_atomic_async_check() to establish if a 1157 * given update can be committed asynchronously, that is, if it can 1158 * jump ahead of the state currently queued for update. 1159 * 1160 * RETURNS: 1161 * 1162 * Return 0 on success and any error returned indicates that the update 1163 * can not be applied in asynchronous manner. 1164 */ 1165 int (*atomic_async_check)(struct drm_plane *plane, 1166 struct drm_plane_state *state); 1167 1168 /** 1169 * @atomic_async_update: 1170 * 1171 * Drivers should set this function pointer to perform asynchronous 1172 * updates of planes, that is, jump ahead of the currently queued 1173 * state and update the plane. Here async means "not vblank 1174 * synchronized". 1175 * 1176 * This hook is called by drm_atomic_helper_async_commit(). 1177 * 1178 * An async update will happen on legacy cursor updates. An async 1179 * update won't happen if there is an outstanding commit modifying 1180 * the same plane. 1181 * 1182 * Note that unlike &drm_plane_helper_funcs.atomic_update this hook 1183 * takes the new &drm_plane_state as parameter. When doing async_update 1184 * drivers shouldn't replace the &drm_plane_state but update the 1185 * current one with the new plane configurations in the new 1186 * plane_state. 1187 * 1188 * Drivers should also swap the framebuffers between current plane 1189 * state (&drm_plane.state) and new_state. 1190 * This is required since cleanup for async commits is performed on 1191 * the new state, rather than old state like for traditional commits. 1192 * Since we want to give up the reference on the current (old) fb 1193 * instead of our brand new one, swap them in the driver during the 1194 * async commit. 1195 * 1196 * FIXME: 1197 * - It only works for single plane updates 1198 * - Async Pageflips are not supported yet 1199 * - Some hw might still scan out the old buffer until the next 1200 * vblank, however we let go of the fb references as soon as 1201 * we run this hook. For now drivers must implement their own workers 1202 * for deferring if needed, until a common solution is created. 1203 */ 1204 void (*atomic_async_update)(struct drm_plane *plane, 1205 struct drm_plane_state *new_state); 1206 }; 1207 1208 /** 1209 * drm_plane_helper_add - sets the helper vtable for a plane 1210 * @plane: DRM plane 1211 * @funcs: helper vtable to set for @plane 1212 */ 1213 static inline void drm_plane_helper_add(struct drm_plane *plane, 1214 const struct drm_plane_helper_funcs *funcs) 1215 { 1216 plane->helper_private = funcs; 1217 } 1218 1219 /** 1220 * struct drm_mode_config_helper_funcs - global modeset helper operations 1221 * 1222 * These helper functions are used by the atomic helpers. 1223 */ 1224 struct drm_mode_config_helper_funcs { 1225 /** 1226 * @atomic_commit_tail: 1227 * 1228 * This hook is used by the default atomic_commit() hook implemented in 1229 * drm_atomic_helper_commit() together with the nonblocking commit 1230 * helpers (see drm_atomic_helper_setup_commit() for a starting point) 1231 * to implement blocking and nonblocking commits easily. It is not used 1232 * by the atomic helpers 1233 * 1234 * This function is called when the new atomic state has already been 1235 * swapped into the various state pointers. The passed in state 1236 * therefore contains copies of the old/previous state. This hook should 1237 * commit the new state into hardware. Note that the helpers have 1238 * already waited for preceeding atomic commits and fences, but drivers 1239 * can add more waiting calls at the start of their implementation, e.g. 1240 * to wait for driver-internal request for implicit syncing, before 1241 * starting to commit the update to the hardware. 1242 * 1243 * After the atomic update is committed to the hardware this hook needs 1244 * to call drm_atomic_helper_commit_hw_done(). Then wait for the upate 1245 * to be executed by the hardware, for example using 1246 * drm_atomic_helper_wait_for_vblanks() or 1247 * drm_atomic_helper_wait_for_flip_done(), and then clean up the old 1248 * framebuffers using drm_atomic_helper_cleanup_planes(). 1249 * 1250 * When disabling a CRTC this hook _must_ stall for the commit to 1251 * complete. Vblank waits don't work on disabled CRTC, hence the core 1252 * can't take care of this. And it also can't rely on the vblank event, 1253 * since that can be signalled already when the screen shows black, 1254 * which can happen much earlier than the last hardware access needed to 1255 * shut off the display pipeline completely. 1256 * 1257 * This hook is optional, the default implementation is 1258 * drm_atomic_helper_commit_tail(). 1259 */ 1260 void (*atomic_commit_tail)(struct drm_atomic_state *state); 1261 }; 1262 1263 #endif 1264