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