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