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 51struct drm_writeback_connector; 52struct drm_writeback_job; 53 54enum 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 and the new atomic 63 * modesetting helpers. 64 */ 65struct 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 hardware 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. 220 * 221 * Note that the display pipe is completely off when this function is 222 * called. Atomic drivers which need hardware to be running before they 223 * program the new display mode (e.g. because they implement runtime PM) 224 * should not use this hook. This is because the helper library calls 225 * this hook only once per mode change and not every time the display 226 * pipeline is suspended using either DPMS or the new "ACTIVE" property. 227 * Which means register values set in this callback might get reset when 228 * the CRTC is suspended, but not restored. Such drivers should instead 229 * move all their CRTC setup into the @atomic_enable callback. 230 * 231 * This callback is optional. 232 */ 233 void (*mode_set_nofb)(struct drm_crtc *crtc); 234 235 /** 236 * @mode_set_base: 237 * 238 * This callback is used by the legacy CRTC helpers to set a new 239 * framebuffer and scanout position. It is optional and used as an 240 * optimized fast-path instead of a full mode set operation with all the 241 * resulting flickering. If it is not present 242 * drm_crtc_helper_set_config() will fall back to a full modeset, using 243 * the @mode_set callback. Since it can't update other planes it's 244 * incompatible with atomic modeset support. 245 * 246 * This callback is only used by the CRTC helpers and deprecated. 247 * 248 * RETURNS: 249 * 250 * 0 on success or a negative error code on failure. 251 */ 252 int (*mode_set_base)(struct drm_crtc *crtc, int x, int y, 253 struct drm_framebuffer *old_fb); 254 255 /** 256 * @mode_set_base_atomic: 257 * 258 * This callback is used by the fbdev helpers to set a new framebuffer 259 * and scanout without sleeping, i.e. from an atomic calling context. It 260 * is only used to implement kgdb support. 261 * 262 * This callback is optional and only needed for kgdb support in the fbdev 263 * helpers. 264 * 265 * RETURNS: 266 * 267 * 0 on success or a negative error code on failure. 268 */ 269 int (*mode_set_base_atomic)(struct drm_crtc *crtc, 270 struct drm_framebuffer *fb, int x, int y, 271 enum mode_set_atomic); 272 273 /** 274 * @disable: 275 * 276 * This callback should be used to disable the CRTC. With the atomic 277 * drivers it is called after all encoders connected to this CRTC have 278 * been shut off already using their own 279 * &drm_encoder_helper_funcs.disable hook. If that sequence is too 280 * simple drivers can just add their own hooks and call it from this 281 * CRTC callback here by looping over all encoders connected to it using 282 * for_each_encoder_on_crtc(). 283 * 284 * This hook is used both by legacy CRTC helpers and atomic helpers. 285 * Atomic drivers don't need to implement it if there's no need to 286 * disable anything at the CRTC level. To ensure that runtime PM 287 * handling (using either DPMS or the new "ACTIVE" property) works 288 * @disable must be the inverse of @atomic_enable for atomic drivers. 289 * Atomic drivers should consider to use @atomic_disable instead of 290 * this one. 291 * 292 * NOTE: 293 * 294 * With legacy CRTC helpers there's a big semantic difference between 295 * @disable and other hooks (like @prepare or @dpms) used to shut down a 296 * CRTC: @disable is only called when also logically disabling the 297 * display pipeline and needs to release any resources acquired in 298 * @mode_set (like shared PLLs, or again release pinned framebuffers). 299 * 300 * Therefore @disable must be the inverse of @mode_set plus @commit for 301 * drivers still using legacy CRTC helpers, which is different from the 302 * rules under atomic. 303 */ 304 void (*disable)(struct drm_crtc *crtc); 305 306 /** 307 * @atomic_check: 308 * 309 * Drivers should check plane-update related CRTC constraints in this 310 * hook. They can also check mode related limitations but need to be 311 * aware of the calling order, since this hook is used by 312 * drm_atomic_helper_check_planes() whereas the preparations needed to 313 * check output routing and the display mode is done in 314 * drm_atomic_helper_check_modeset(). Therefore drivers that want to 315 * check output routing and display mode constraints in this callback 316 * must ensure that drm_atomic_helper_check_modeset() has been called 317 * beforehand. This is calling order used by the default helper 318 * implementation in drm_atomic_helper_check(). 319 * 320 * When using drm_atomic_helper_check_planes() this hook is called 321 * after the &drm_plane_helper_funcs.atomic_check hook for planes, which 322 * allows drivers to assign shared resources requested by planes in this 323 * callback here. For more complicated dependencies the driver can call 324 * the provided check helpers multiple times until the computed state 325 * has a final configuration and everything has been checked. 326 * 327 * This function is also allowed to inspect any other object's state and 328 * can add more state objects to the atomic commit if needed. Care must 329 * be taken though to ensure that state check and compute functions for 330 * these added states are all called, and derived state in other objects 331 * all updated. Again the recommendation is to just call check helpers 332 * until a maximal configuration is reached. 333 * 334 * This callback is used by the atomic modeset helpers, but it is 335 * optional. 336 * 337 * NOTE: 338 * 339 * This function is called in the check phase of an atomic update. The 340 * driver is not allowed to change anything outside of the free-standing 341 * state object passed-in. 342 * 343 * Also beware that userspace can request its own custom modes, neither 344 * core nor helpers filter modes to the list of probe modes reported by 345 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 346 * that modes are filtered consistently put any CRTC constraints and 347 * limits checks into @mode_valid. 348 * 349 * RETURNS: 350 * 351 * 0 on success, -EINVAL if the state or the transition can't be 352 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 353 * attempt to obtain another state object ran into a &drm_modeset_lock 354 * deadlock. 355 */ 356 int (*atomic_check)(struct drm_crtc *crtc, 357 struct drm_atomic_state *state); 358 359 /** 360 * @atomic_begin: 361 * 362 * Drivers should prepare for an atomic update of multiple planes on 363 * a CRTC in this hook. Depending upon hardware this might be vblank 364 * evasion, blocking updates by setting bits or doing preparatory work 365 * for e.g. manual update display. 366 * 367 * This hook is called before any plane commit functions are called. 368 * 369 * Note that the power state of the display pipe when this function is 370 * called depends upon the exact helpers and calling sequence the driver 371 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 372 * the tradeoffs and variants of plane commit helpers. 373 * 374 * This callback is used by the atomic modeset helpers, but it is 375 * optional. 376 */ 377 void (*atomic_begin)(struct drm_crtc *crtc, 378 struct drm_atomic_state *state); 379 /** 380 * @atomic_flush: 381 * 382 * Drivers should finalize an atomic update of multiple planes on 383 * a CRTC in this hook. Depending upon hardware this might include 384 * checking that vblank evasion was successful, unblocking updates by 385 * setting bits or setting the GO bit to flush out all updates. 386 * 387 * Simple hardware or hardware with special requirements can commit and 388 * flush out all updates for all planes from this hook and forgo all the 389 * other commit hooks for plane updates. 390 * 391 * This hook is called after any plane commit functions are called. 392 * 393 * Note that the power state of the display pipe when this function is 394 * called depends upon the exact helpers and calling sequence the driver 395 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 396 * the tradeoffs and variants of plane commit helpers. 397 * 398 * This callback is used by the atomic modeset helpers, but it is 399 * optional. 400 */ 401 void (*atomic_flush)(struct drm_crtc *crtc, 402 struct drm_atomic_state *state); 403 404 /** 405 * @atomic_enable: 406 * 407 * This callback should be used to enable the CRTC. With the atomic 408 * drivers it is called before all encoders connected to this CRTC are 409 * enabled through the encoder's own &drm_encoder_helper_funcs.enable 410 * hook. If that sequence is too simple drivers can just add their own 411 * hooks and call it from this CRTC callback here by looping over all 412 * encoders connected to it using for_each_encoder_on_crtc(). 413 * 414 * This hook is used only by atomic helpers, for symmetry with 415 * @atomic_disable. Atomic drivers don't need to implement it if there's 416 * no need to enable anything at the CRTC level. To ensure that runtime 417 * PM handling (using either DPMS or the new "ACTIVE" property) works 418 * @atomic_enable must be the inverse of @atomic_disable for atomic 419 * drivers. 420 * 421 * This function is optional. 422 */ 423 void (*atomic_enable)(struct drm_crtc *crtc, 424 struct drm_atomic_state *state); 425 426 /** 427 * @atomic_disable: 428 * 429 * This callback should be used to disable the CRTC. With the atomic 430 * drivers it is called after all encoders connected to this CRTC have 431 * been shut off already using their own 432 * &drm_encoder_helper_funcs.disable hook. If that sequence is too 433 * simple drivers can just add their own hooks and call it from this 434 * CRTC callback here by looping over all encoders connected to it using 435 * for_each_encoder_on_crtc(). 436 * 437 * This hook is used only by atomic helpers. Atomic drivers don't 438 * need to implement it if there's no need to disable anything at the 439 * CRTC level. 440 * 441 * This function is optional. 442 */ 443 void (*atomic_disable)(struct drm_crtc *crtc, 444 struct drm_atomic_state *state); 445 446 /** 447 * @get_scanout_position: 448 * 449 * Called by vblank timestamping code. 450 * 451 * Returns the current display scanout position from a CRTC and an 452 * optional accurate ktime_get() timestamp of when the position was 453 * measured. Note that this is a helper callback which is only used 454 * if a driver uses drm_crtc_vblank_helper_get_vblank_timestamp() 455 * for the @drm_crtc_funcs.get_vblank_timestamp callback. 456 * 457 * Parameters: 458 * 459 * crtc: 460 * The CRTC. 461 * in_vblank_irq: 462 * True when called from drm_crtc_handle_vblank(). Some drivers 463 * need to apply some workarounds for gpu-specific vblank irq 464 * quirks if the flag is set. 465 * vpos: 466 * Target location for current vertical scanout position. 467 * hpos: 468 * Target location for current horizontal scanout position. 469 * stime: 470 * Target location for timestamp taken immediately before 471 * scanout position query. Can be NULL to skip timestamp. 472 * etime: 473 * Target location for timestamp taken immediately after 474 * scanout position query. Can be NULL to skip timestamp. 475 * mode: 476 * Current display timings. 477 * 478 * Returns vpos as a positive number while in active scanout area. 479 * Returns vpos as a negative number inside vblank, counting the number 480 * of scanlines to go until end of vblank, e.g., -1 means "one scanline 481 * until start of active scanout / end of vblank." 482 * 483 * Returns: 484 * 485 * True on success, false if a reliable scanout position counter could 486 * not be read out. 487 */ 488 bool (*get_scanout_position)(struct drm_crtc *crtc, 489 bool in_vblank_irq, int *vpos, int *hpos, 490 ktime_t *stime, ktime_t *etime, 491 const struct drm_display_mode *mode); 492}; 493 494/** 495 * drm_crtc_helper_add - sets the helper vtable for a crtc 496 * @crtc: DRM CRTC 497 * @funcs: helper vtable to set for @crtc 498 */ 499static inline void drm_crtc_helper_add(struct drm_crtc *crtc, 500 const struct drm_crtc_helper_funcs *funcs) 501{ 502 crtc->helper_private = funcs; 503} 504 505/** 506 * struct drm_encoder_helper_funcs - helper operations for encoders 507 * 508 * These hooks are used by the legacy CRTC helpers and the new atomic 509 * modesetting helpers. 510 */ 511struct drm_encoder_helper_funcs { 512 /** 513 * @dpms: 514 * 515 * Callback to control power levels on the encoder. If the mode passed in 516 * is unsupported, the provider must use the next lowest power level. 517 * This is used by the legacy encoder helpers to implement DPMS 518 * functionality in drm_helper_connector_dpms(). 519 * 520 * This callback is also used to disable an encoder by calling it with 521 * DRM_MODE_DPMS_OFF if the @disable hook isn't used. 522 * 523 * This callback is used by the legacy CRTC helpers. Atomic helpers 524 * also support using this hook for enabling and disabling an encoder to 525 * facilitate transitions to atomic, but it is deprecated. Instead 526 * @enable and @disable should be used. 527 */ 528 void (*dpms)(struct drm_encoder *encoder, int mode); 529 530 /** 531 * @mode_valid: 532 * 533 * This callback is used to check if a specific mode is valid in this 534 * encoder. This should be implemented if the encoder has some sort 535 * of restriction in the modes it can display. For example, a given 536 * encoder may be responsible to set a clock value. If the clock can 537 * not produce all the values for the available modes then this callback 538 * can be used to restrict the number of modes to only the ones that 539 * can be displayed. 540 * 541 * This hook is used by the probe helpers to filter the mode list in 542 * drm_helper_probe_single_connector_modes(), and it is used by the 543 * atomic helpers to validate modes supplied by userspace in 544 * drm_atomic_helper_check_modeset(). 545 * 546 * This function is optional. 547 * 548 * NOTE: 549 * 550 * Since this function is both called from the check phase of an atomic 551 * commit, and the mode validation in the probe paths it is not allowed 552 * to look at anything else but the passed-in mode, and validate it 553 * against configuration-invariant hardware constraints. Any further 554 * limits which depend upon the configuration can only be checked in 555 * @mode_fixup or @atomic_check. 556 * 557 * RETURNS: 558 * 559 * drm_mode_status Enum 560 */ 561 enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc, 562 const struct drm_display_mode *mode); 563 564 /** 565 * @mode_fixup: 566 * 567 * This callback is used to validate and adjust a mode. The parameter 568 * mode is the display mode that should be fed to the next element in 569 * the display chain, either the final &drm_connector or a &drm_bridge. 570 * The parameter adjusted_mode is the input mode the encoder requires. It 571 * can be modified by this callback and does not need to match mode. See 572 * also &drm_crtc_state.adjusted_mode for more details. 573 * 574 * This function is used by both legacy CRTC helpers and atomic helpers. 575 * This hook is optional. 576 * 577 * NOTE: 578 * 579 * This function is called in the check phase of atomic modesets, which 580 * can be aborted for any reason (including on userspace's request to 581 * just check whether a configuration would be possible). Atomic drivers 582 * MUST NOT touch any persistent state (hardware or software) or data 583 * structures except the passed in adjusted_mode parameter. 584 * 585 * This is in contrast to the legacy CRTC helpers where this was 586 * allowed. 587 * 588 * Atomic drivers which need to inspect and adjust more state should 589 * instead use the @atomic_check callback. If @atomic_check is used, 590 * this hook isn't called since @atomic_check allows a strict superset 591 * of the functionality of @mode_fixup. 592 * 593 * Also beware that userspace can request its own custom modes, neither 594 * core nor helpers filter modes to the list of probe modes reported by 595 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 596 * that modes are filtered consistently put any encoder constraints and 597 * limits checks into @mode_valid. 598 * 599 * RETURNS: 600 * 601 * True if an acceptable configuration is possible, false if the modeset 602 * operation should be rejected. 603 */ 604 bool (*mode_fixup)(struct drm_encoder *encoder, 605 const struct drm_display_mode *mode, 606 struct drm_display_mode *adjusted_mode); 607 608 /** 609 * @prepare: 610 * 611 * This callback should prepare the encoder for a subsequent modeset, 612 * which in practice means the driver should disable the encoder if it 613 * is running. Most drivers ended up implementing this by calling their 614 * @dpms hook with DRM_MODE_DPMS_OFF. 615 * 616 * This callback is used by the legacy CRTC helpers. Atomic helpers 617 * also support using this hook for disabling an encoder to facilitate 618 * transitions to atomic, but it is deprecated. Instead @disable should 619 * be used. 620 */ 621 void (*prepare)(struct drm_encoder *encoder); 622 623 /** 624 * @commit: 625 * 626 * This callback should commit the new mode on the encoder after a modeset, 627 * which in practice means the driver should enable the encoder. Most 628 * drivers ended up implementing this by calling their @dpms hook with 629 * DRM_MODE_DPMS_ON. 630 * 631 * This callback is used by the legacy CRTC helpers. Atomic helpers 632 * also support using this hook for enabling an encoder to facilitate 633 * transitions to atomic, but it is deprecated. Instead @enable should 634 * be used. 635 */ 636 void (*commit)(struct drm_encoder *encoder); 637 638 /** 639 * @mode_set: 640 * 641 * This callback is used to update the display mode of an encoder. 642 * 643 * Note that the display pipe is completely off when this function is 644 * called. Drivers which need hardware to be running before they program 645 * the new display mode (because they implement runtime PM) should not 646 * use this hook, because the helper library calls it only once and not 647 * every time the display pipeline is suspend using either DPMS or the 648 * new "ACTIVE" property. Such drivers should instead move all their 649 * encoder setup into the @enable callback. 650 * 651 * This callback is used both by the legacy CRTC helpers and the atomic 652 * modeset helpers. It is optional in the atomic helpers. 653 * 654 * NOTE: 655 * 656 * If the driver uses the atomic modeset helpers and needs to inspect 657 * the connector state or connector display info during mode setting, 658 * @atomic_mode_set can be used instead. 659 */ 660 void (*mode_set)(struct drm_encoder *encoder, 661 struct drm_display_mode *mode, 662 struct drm_display_mode *adjusted_mode); 663 664 /** 665 * @atomic_mode_set: 666 * 667 * This callback is used to update the display mode of an encoder. 668 * 669 * Note that the display pipe is completely off when this function is 670 * called. Drivers which need hardware to be running before they program 671 * the new display mode (because they implement runtime PM) should not 672 * use this hook, because the helper library calls it only once and not 673 * every time the display pipeline is suspended using either DPMS or the 674 * new "ACTIVE" property. Such drivers should instead move all their 675 * encoder setup into the @enable callback. 676 * 677 * This callback is used by the atomic modeset helpers in place of the 678 * @mode_set callback, if set by the driver. It is optional and should 679 * be used instead of @mode_set if the driver needs to inspect the 680 * connector state or display info, since there is no direct way to 681 * go from the encoder to the current connector. 682 */ 683 void (*atomic_mode_set)(struct drm_encoder *encoder, 684 struct drm_crtc_state *crtc_state, 685 struct drm_connector_state *conn_state); 686 687 /** 688 * @detect: 689 * 690 * This callback can be used by drivers who want to do detection on the 691 * encoder object instead of in connector functions. 692 * 693 * It is not used by any helper and therefore has purely driver-specific 694 * semantics. New drivers shouldn't use this and instead just implement 695 * their own private callbacks. 696 * 697 * FIXME: 698 * 699 * This should just be converted into a pile of driver vfuncs. 700 * Currently radeon, amdgpu and nouveau are using it. 701 */ 702 enum drm_connector_status (*detect)(struct drm_encoder *encoder, 703 struct drm_connector *connector); 704 705 /** 706 * @atomic_disable: 707 * 708 * This callback should be used to disable the encoder. With the atomic 709 * drivers it is called before this encoder's CRTC has been shut off 710 * using their own &drm_crtc_helper_funcs.atomic_disable hook. If that 711 * sequence is too simple drivers can just add their own driver private 712 * encoder hooks and call them from CRTC's callback by looping over all 713 * encoders connected to it using for_each_encoder_on_crtc(). 714 * 715 * This callback is a variant of @disable that provides the atomic state 716 * to the driver. If @atomic_disable is implemented, @disable is not 717 * called by the helpers. 718 * 719 * This hook is only used by atomic helpers. Atomic drivers don't need 720 * to implement it if there's no need to disable anything at the encoder 721 * level. To ensure that runtime PM handling (using either DPMS or the 722 * new "ACTIVE" property) works @atomic_disable must be the inverse of 723 * @atomic_enable. 724 */ 725 void (*atomic_disable)(struct drm_encoder *encoder, 726 struct drm_atomic_state *state); 727 728 /** 729 * @atomic_enable: 730 * 731 * This callback should be used to enable the encoder. It is called 732 * after this encoder's CRTC has been enabled using their own 733 * &drm_crtc_helper_funcs.atomic_enable hook. If that sequence is 734 * too simple drivers can just add their own driver private encoder 735 * hooks and call them from CRTC's callback by looping over all encoders 736 * connected to it using for_each_encoder_on_crtc(). 737 * 738 * This callback is a variant of @enable that provides the atomic state 739 * to the driver. If @atomic_enable is implemented, @enable is not 740 * called by the helpers. 741 * 742 * This hook is only used by atomic helpers, it is the opposite of 743 * @atomic_disable. Atomic drivers don't need to implement it if there's 744 * no need to enable anything at the encoder level. To ensure that 745 * runtime PM handling works @atomic_enable must be the inverse of 746 * @atomic_disable. 747 */ 748 void (*atomic_enable)(struct drm_encoder *encoder, 749 struct drm_atomic_state *state); 750 751 /** 752 * @disable: 753 * 754 * This callback should be used to disable the encoder. With the atomic 755 * drivers it is called before this encoder's CRTC has been shut off 756 * using their own &drm_crtc_helper_funcs.disable hook. If that 757 * sequence is too simple drivers can just add their own driver private 758 * encoder hooks and call them from CRTC's callback by looping over all 759 * encoders connected to it using for_each_encoder_on_crtc(). 760 * 761 * This hook is used both by legacy CRTC helpers and atomic helpers. 762 * Atomic drivers don't need to implement it if there's no need to 763 * disable anything at the encoder level. To ensure that runtime PM 764 * handling (using either DPMS or the new "ACTIVE" property) works 765 * @disable must be the inverse of @enable for atomic drivers. 766 * 767 * For atomic drivers also consider @atomic_disable and save yourself 768 * from having to read the NOTE below! 769 * 770 * NOTE: 771 * 772 * With legacy CRTC helpers there's a big semantic difference between 773 * @disable and other hooks (like @prepare or @dpms) used to shut down a 774 * encoder: @disable is only called when also logically disabling the 775 * display pipeline and needs to release any resources acquired in 776 * @mode_set (like shared PLLs, or again release pinned framebuffers). 777 * 778 * Therefore @disable must be the inverse of @mode_set plus @commit for 779 * drivers still using legacy CRTC helpers, which is different from the 780 * rules under atomic. 781 */ 782 void (*disable)(struct drm_encoder *encoder); 783 784 /** 785 * @enable: 786 * 787 * This callback should be used to enable the encoder. With the atomic 788 * drivers it is called after this encoder's CRTC has been enabled using 789 * their own &drm_crtc_helper_funcs.enable hook. If that sequence is 790 * too simple drivers can just add their own driver private encoder 791 * hooks and call them from CRTC's callback by looping over all encoders 792 * connected to it using for_each_encoder_on_crtc(). 793 * 794 * This hook is only used by atomic helpers, it is the opposite of 795 * @disable. Atomic drivers don't need to implement it if there's no 796 * need to enable anything at the encoder level. To ensure that 797 * runtime PM handling (using either DPMS or the new "ACTIVE" property) 798 * works @enable must be the inverse of @disable for atomic drivers. 799 */ 800 void (*enable)(struct drm_encoder *encoder); 801 802 /** 803 * @atomic_check: 804 * 805 * This callback is used to validate encoder state for atomic drivers. 806 * Since the encoder is the object connecting the CRTC and connector it 807 * gets passed both states, to be able to validate interactions and 808 * update the CRTC to match what the encoder needs for the requested 809 * connector. 810 * 811 * Since this provides a strict superset of the functionality of 812 * @mode_fixup (the requested and adjusted modes are both available 813 * through the passed in &struct drm_crtc_state) @mode_fixup is not 814 * called when @atomic_check is implemented. 815 * 816 * This function is used by the atomic helpers, but it is optional. 817 * 818 * NOTE: 819 * 820 * This function is called in the check phase of an atomic update. The 821 * driver is not allowed to change anything outside of the free-standing 822 * state objects passed-in or assembled in the overall &drm_atomic_state 823 * update tracking structure. 824 * 825 * Also beware that userspace can request its own custom modes, neither 826 * core nor helpers filter modes to the list of probe modes reported by 827 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 828 * that modes are filtered consistently put any encoder constraints and 829 * limits checks into @mode_valid. 830 * 831 * RETURNS: 832 * 833 * 0 on success, -EINVAL if the state or the transition can't be 834 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 835 * attempt to obtain another state object ran into a &drm_modeset_lock 836 * deadlock. 837 */ 838 int (*atomic_check)(struct drm_encoder *encoder, 839 struct drm_crtc_state *crtc_state, 840 struct drm_connector_state *conn_state); 841}; 842 843/** 844 * drm_encoder_helper_add - sets the helper vtable for an encoder 845 * @encoder: DRM encoder 846 * @funcs: helper vtable to set for @encoder 847 */ 848static inline void drm_encoder_helper_add(struct drm_encoder *encoder, 849 const struct drm_encoder_helper_funcs *funcs) 850{ 851 encoder->helper_private = funcs; 852} 853 854/** 855 * struct drm_connector_helper_funcs - helper operations for connectors 856 * 857 * These functions are used by the atomic and legacy modeset helpers and by the 858 * probe helpers. 859 */ 860struct drm_connector_helper_funcs { 861 /** 862 * @get_modes: 863 * 864 * This function should fill in all modes currently valid for the sink 865 * into the &drm_connector.probed_modes list. It should also update the 866 * EDID property by calling drm_connector_update_edid_property(). 867 * 868 * The usual way to implement this is to cache the EDID retrieved in the 869 * probe callback somewhere in the driver-private connector structure. 870 * In this function drivers then parse the modes in the EDID and add 871 * them by calling drm_add_edid_modes(). But connectors that drive a 872 * fixed panel can also manually add specific modes using 873 * drm_mode_probed_add(). Drivers which manually add modes should also 874 * make sure that the &drm_connector.display_info, 875 * &drm_connector.width_mm and &drm_connector.height_mm fields are 876 * filled in. 877 * 878 * Note that the caller function will automatically add standard VESA 879 * DMT modes up to 1024x768 if the .get_modes() helper operation returns 880 * no mode and if the connector status is connector_status_connected or 881 * connector_status_unknown. There is no need to call 882 * drm_add_modes_noedid() manually in that case. 883 * 884 * Virtual drivers that just want some standard VESA mode with a given 885 * resolution can call drm_add_modes_noedid(), and mark the preferred 886 * one using drm_set_preferred_mode(). 887 * 888 * This function is only called after the @detect hook has indicated 889 * that a sink is connected and when the EDID isn't overridden through 890 * sysfs or the kernel commandline. 891 * 892 * This callback is used by the probe helpers in e.g. 893 * drm_helper_probe_single_connector_modes(). 894 * 895 * To avoid races with concurrent connector state updates, the helper 896 * libraries always call this with the &drm_mode_config.connection_mutex 897 * held. Because of this it's safe to inspect &drm_connector->state. 898 * 899 * RETURNS: 900 * 901 * The number of modes added by calling drm_mode_probed_add(). Return 0 902 * on failures (no modes) instead of negative error codes. 903 */ 904 int (*get_modes)(struct drm_connector *connector); 905 906 /** 907 * @detect_ctx: 908 * 909 * Check to see if anything is attached to the connector. The parameter 910 * force is set to false whilst polling, true when checking the 911 * connector due to a user request. force can be used by the driver to 912 * avoid expensive, destructive operations during automated probing. 913 * 914 * This callback is optional, if not implemented the connector will be 915 * considered as always being attached. 916 * 917 * This is the atomic version of &drm_connector_funcs.detect. 918 * 919 * To avoid races against concurrent connector state updates, the 920 * helper libraries always call this with ctx set to a valid context, 921 * and &drm_mode_config.connection_mutex will always be locked with 922 * the ctx parameter set to this ctx. This allows taking additional 923 * locks as required. 924 * 925 * RETURNS: 926 * 927 * &drm_connector_status indicating the connector's status, 928 * or the error code returned by drm_modeset_lock(), -EDEADLK. 929 */ 930 int (*detect_ctx)(struct drm_connector *connector, 931 struct drm_modeset_acquire_ctx *ctx, 932 bool force); 933 934 /** 935 * @mode_valid: 936 * 937 * Callback to validate a mode for a connector, irrespective of the 938 * specific display configuration. 939 * 940 * This callback is used by the probe helpers to filter the mode list 941 * (which is usually derived from the EDID data block from the sink). 942 * See e.g. drm_helper_probe_single_connector_modes(). 943 * 944 * This function is optional. 945 * 946 * NOTE: 947 * 948 * This only filters the mode list supplied to userspace in the 949 * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid, 950 * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid, 951 * which are also called by the atomic helpers from 952 * drm_atomic_helper_check_modeset(). This allows userspace to force and 953 * ignore sink constraint (like the pixel clock limits in the screen's 954 * EDID), which is useful for e.g. testing, or working around a broken 955 * EDID. Any source hardware constraint (which always need to be 956 * enforced) therefore should be checked in one of the above callbacks, 957 * and not this one here. 958 * 959 * To avoid races with concurrent connector state updates, the helper 960 * libraries always call this with the &drm_mode_config.connection_mutex 961 * held. Because of this it's safe to inspect &drm_connector->state. 962 * 963 * RETURNS: 964 * 965 * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum 966 * drm_mode_status. 967 */ 968 enum drm_mode_status (*mode_valid)(struct drm_connector *connector, 969 struct drm_display_mode *mode); 970 971 /** 972 * @mode_valid_ctx: 973 * 974 * Callback to validate a mode for a connector, irrespective of the 975 * specific display configuration. 976 * 977 * This callback is used by the probe helpers to filter the mode list 978 * (which is usually derived from the EDID data block from the sink). 979 * See e.g. drm_helper_probe_single_connector_modes(). 980 * 981 * This function is optional, and is the atomic version of 982 * &drm_connector_helper_funcs.mode_valid. 983 * 984 * To allow for accessing the atomic state of modesetting objects, the 985 * helper libraries always call this with ctx set to a valid context, 986 * and &drm_mode_config.connection_mutex will always be locked with 987 * the ctx parameter set to @ctx. This allows for taking additional 988 * locks as required. 989 * 990 * Even though additional locks may be acquired, this callback is 991 * still expected not to take any constraints into account which would 992 * be influenced by the currently set display state - such constraints 993 * should be handled in the driver's atomic check. For example, if a 994 * connector shares display bandwidth with other connectors then it 995 * would be ok to validate the minimum bandwidth requirement of a mode 996 * against the maximum possible bandwidth of the connector. But it 997 * wouldn't be ok to take the current bandwidth usage of other 998 * connectors into account, as this would change depending on the 999 * display state. 1000 * 1001 * Returns: 1002 * 0 if &drm_connector_helper_funcs.mode_valid_ctx succeeded and wrote 1003 * the &enum drm_mode_status value to @status, or a negative error 1004 * code otherwise. 1005 * 1006 */ 1007 int (*mode_valid_ctx)(struct drm_connector *connector, 1008 struct drm_display_mode *mode, 1009 struct drm_modeset_acquire_ctx *ctx, 1010 enum drm_mode_status *status); 1011 1012 /** 1013 * @best_encoder: 1014 * 1015 * This function should select the best encoder for the given connector. 1016 * 1017 * This function is used by both the atomic helpers (in the 1018 * drm_atomic_helper_check_modeset() function) and in the legacy CRTC 1019 * helpers. 1020 * 1021 * NOTE: 1022 * 1023 * In atomic drivers this function is called in the check phase of an 1024 * atomic update. The driver is not allowed to change or inspect 1025 * anything outside of arguments passed-in. Atomic drivers which need to 1026 * inspect dynamic configuration state should instead use 1027 * @atomic_best_encoder. 1028 * 1029 * You can leave this function to NULL if the connector is only 1030 * attached to a single encoder. In this case, the core will call 1031 * drm_connector_get_single_encoder() for you. 1032 * 1033 * RETURNS: 1034 * 1035 * Encoder that should be used for the given connector and connector 1036 * state, or NULL if no suitable encoder exists. Note that the helpers 1037 * will ensure that encoders aren't used twice, drivers should not check 1038 * for this. 1039 */ 1040 struct drm_encoder *(*best_encoder)(struct drm_connector *connector); 1041 1042 /** 1043 * @atomic_best_encoder: 1044 * 1045 * This is the atomic version of @best_encoder for atomic drivers which 1046 * need to select the best encoder depending upon the desired 1047 * configuration and can't select it statically. 1048 * 1049 * This function is used by drm_atomic_helper_check_modeset(). 1050 * If it is not implemented, the core will fallback to @best_encoder 1051 * (or drm_connector_get_single_encoder() if @best_encoder is NULL). 1052 * 1053 * NOTE: 1054 * 1055 * This function is called in the check phase of an atomic update. The 1056 * driver is not allowed to change anything outside of the 1057 * &drm_atomic_state update tracking structure passed in. 1058 * 1059 * RETURNS: 1060 * 1061 * Encoder that should be used for the given connector and connector 1062 * state, or NULL if no suitable encoder exists. Note that the helpers 1063 * will ensure that encoders aren't used twice, drivers should not check 1064 * for this. 1065 */ 1066 struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector, 1067 struct drm_atomic_state *state); 1068 1069 /** 1070 * @atomic_check: 1071 * 1072 * This hook is used to validate connector state. This function is 1073 * called from &drm_atomic_helper_check_modeset, and is called when 1074 * a connector property is set, or a modeset on the crtc is forced. 1075 * 1076 * Because &drm_atomic_helper_check_modeset may be called multiple times, 1077 * this function should handle being called multiple times as well. 1078 * 1079 * This function is also allowed to inspect any other object's state and 1080 * can add more state objects to the atomic commit if needed. Care must 1081 * be taken though to ensure that state check and compute functions for 1082 * these added states are all called, and derived state in other objects 1083 * all updated. Again the recommendation is to just call check helpers 1084 * until a maximal configuration is reached. 1085 * 1086 * NOTE: 1087 * 1088 * This function is called in the check phase of an atomic update. The 1089 * driver is not allowed to change anything outside of the free-standing 1090 * state objects passed-in or assembled in the overall &drm_atomic_state 1091 * update tracking structure. 1092 * 1093 * RETURNS: 1094 * 1095 * 0 on success, -EINVAL if the state or the transition can't be 1096 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 1097 * attempt to obtain another state object ran into a &drm_modeset_lock 1098 * deadlock. 1099 */ 1100 int (*atomic_check)(struct drm_connector *connector, 1101 struct drm_atomic_state *state); 1102 1103 /** 1104 * @atomic_commit: 1105 * 1106 * This hook is to be used by drivers implementing writeback connectors 1107 * that need a point when to commit the writeback job to the hardware. 1108 * The writeback_job to commit is available in the new connector state, 1109 * in &drm_connector_state.writeback_job. 1110 * 1111 * This hook is optional. 1112 * 1113 * This callback is used by the atomic modeset helpers. 1114 */ 1115 void (*atomic_commit)(struct drm_connector *connector, 1116 struct drm_atomic_state *state); 1117 1118 /** 1119 * @prepare_writeback_job: 1120 * 1121 * As writeback jobs contain a framebuffer, drivers may need to 1122 * prepare and clean them up the same way they can prepare and 1123 * clean up framebuffers for planes. This optional connector operation 1124 * is used to support the preparation of writeback jobs. The job 1125 * prepare operation is called from drm_atomic_helper_prepare_planes() 1126 * for struct &drm_writeback_connector connectors only. 1127 * 1128 * This operation is optional. 1129 * 1130 * This callback is used by the atomic modeset helpers. 1131 */ 1132 int (*prepare_writeback_job)(struct drm_writeback_connector *connector, 1133 struct drm_writeback_job *job); 1134 /** 1135 * @cleanup_writeback_job: 1136 * 1137 * This optional connector operation is used to support the 1138 * cleanup of writeback jobs. The job cleanup operation is called 1139 * from the existing drm_writeback_cleanup_job() function, invoked 1140 * both when destroying the job as part of an aborted commit, or when 1141 * the job completes. 1142 * 1143 * This operation is optional. 1144 * 1145 * This callback is used by the atomic modeset helpers. 1146 */ 1147 void (*cleanup_writeback_job)(struct drm_writeback_connector *connector, 1148 struct drm_writeback_job *job); 1149 1150 /** 1151 * @enable_hpd: 1152 * 1153 * Enable hot-plug detection for the connector. 1154 * 1155 * This operation is optional. 1156 * 1157 * This callback is used by the drm_kms_helper_poll_enable() helpers. 1158 * 1159 * This operation does not need to perform any hpd state tracking as 1160 * the DRM core handles that maintenance and ensures the calls to enable 1161 * and disable hpd are balanced. 1162 * 1163 */ 1164 void (*enable_hpd)(struct drm_connector *connector); 1165 1166 /** 1167 * @disable_hpd: 1168 * 1169 * Disable hot-plug detection for the connector. 1170 * 1171 * This operation is optional. 1172 * 1173 * This callback is used by the drm_kms_helper_poll_disable() helpers. 1174 * 1175 * This operation does not need to perform any hpd state tracking as 1176 * the DRM core handles that maintenance and ensures the calls to enable 1177 * and disable hpd are balanced. 1178 * 1179 */ 1180 void (*disable_hpd)(struct drm_connector *connector); 1181}; 1182 1183/** 1184 * drm_connector_helper_add - sets the helper vtable for a connector 1185 * @connector: DRM connector 1186 * @funcs: helper vtable to set for @connector 1187 */ 1188static inline void drm_connector_helper_add(struct drm_connector *connector, 1189 const struct drm_connector_helper_funcs *funcs) 1190{ 1191 connector->helper_private = funcs; 1192} 1193 1194/** 1195 * struct drm_plane_helper_funcs - helper operations for planes 1196 * 1197 * These functions are used by the atomic helpers. 1198 */ 1199struct drm_plane_helper_funcs { 1200 /** 1201 * @prepare_fb: 1202 * 1203 * This hook is to prepare a framebuffer for scanout by e.g. pinning 1204 * its backing storage or relocating it into a contiguous block of 1205 * VRAM. Other possible preparatory work includes flushing caches. 1206 * 1207 * This function must not block for outstanding rendering, since it is 1208 * called in the context of the atomic IOCTL even for async commits to 1209 * be able to return any errors to userspace. Instead the recommended 1210 * way is to fill out the &drm_plane_state.fence of the passed-in 1211 * &drm_plane_state. If the driver doesn't support native fences then 1212 * equivalent functionality should be implemented through private 1213 * members in the plane structure. 1214 * 1215 * For GEM drivers who neither have a @prepare_fb nor @cleanup_fb hook 1216 * set drm_gem_plane_helper_prepare_fb() is called automatically to 1217 * implement this. Other drivers which need additional plane processing 1218 * can call drm_gem_plane_helper_prepare_fb() from their @prepare_fb 1219 * hook. 1220 * 1221 * The resources acquired in @prepare_fb persist after the end of 1222 * the atomic commit. Resources that can be release at the commit's end 1223 * should be acquired in @begin_fb_access and released in @end_fb_access. 1224 * For example, a GEM buffer's pin operation belongs into @prepare_fb to 1225 * keep the buffer pinned after the commit. But a vmap operation for 1226 * shadow-plane helpers belongs into @begin_fb_access, so that atomic 1227 * helpers remove the mapping at the end of the commit. 1228 * 1229 * The helpers will call @cleanup_fb with matching arguments for every 1230 * successful call to this hook. 1231 * 1232 * This callback is used by the atomic modeset helpers, but it is 1233 * optional. See @begin_fb_access for preparing per-commit resources. 1234 * 1235 * RETURNS: 1236 * 1237 * 0 on success or one of the following negative error codes allowed by 1238 * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers 1239 * this callback is the only one which can fail an atomic commit, 1240 * everything else must complete successfully. 1241 */ 1242 int (*prepare_fb)(struct drm_plane *plane, 1243 struct drm_plane_state *new_state); 1244 /** 1245 * @cleanup_fb: 1246 * 1247 * This hook is called to clean up any resources allocated for the given 1248 * framebuffer and plane configuration in @prepare_fb. 1249 * 1250 * This callback is used by the atomic modeset helpers, but it is 1251 * optional. 1252 */ 1253 void (*cleanup_fb)(struct drm_plane *plane, 1254 struct drm_plane_state *old_state); 1255 1256 /** 1257 * @begin_fb_access: 1258 * 1259 * This hook prepares the plane for access during an atomic commit. 1260 * In contrast to @prepare_fb, resources acquired in @begin_fb_access, 1261 * are released at the end of the atomic commit in @end_fb_access. 1262 * 1263 * For example, with shadow-plane helpers, the GEM buffer's vmap 1264 * operation belongs into @begin_fb_access, so that the buffer's 1265 * memory will be unmapped at the end of the commit in @end_fb_access. 1266 * But a GEM buffer's pin operation belongs into @prepare_fb 1267 * to keep the buffer pinned after the commit. 1268 * 1269 * The callback is used by the atomic modeset helpers, but it is optional. 1270 * See @end_fb_cleanup for undoing the effects of @begin_fb_access and 1271 * @prepare_fb for acquiring resources until the next pageflip. 1272 * 1273 * Returns: 1274 * 0 on success, or a negative errno code otherwise. 1275 */ 1276 int (*begin_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state); 1277 1278 /** 1279 * @end_fb_access: 1280 * 1281 * This hook cleans up resources allocated by @begin_fb_access. It it called 1282 * at the end of a commit for the new plane state. 1283 */ 1284 void (*end_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state); 1285 1286 /** 1287 * @atomic_check: 1288 * 1289 * Drivers should check plane specific constraints in this hook. 1290 * 1291 * When using drm_atomic_helper_check_planes() plane's @atomic_check 1292 * hooks are called before the ones for CRTCs, which allows drivers to 1293 * request shared resources that the CRTC controls here. For more 1294 * complicated dependencies the driver can call the provided check helpers 1295 * multiple times until the computed state has a final configuration and 1296 * everything has been checked. 1297 * 1298 * This function is also allowed to inspect any other object's state and 1299 * can add more state objects to the atomic commit if needed. Care must 1300 * be taken though to ensure that state check and compute functions for 1301 * these added states are all called, and derived state in other objects 1302 * all updated. Again the recommendation is to just call check helpers 1303 * until a maximal configuration is reached. 1304 * 1305 * This callback is used by the atomic modeset helpers, but it is 1306 * optional. 1307 * 1308 * NOTE: 1309 * 1310 * This function is called in the check phase of an atomic update. The 1311 * driver is not allowed to change anything outside of the 1312 * &drm_atomic_state update tracking structure. 1313 * 1314 * RETURNS: 1315 * 1316 * 0 on success, -EINVAL if the state or the transition can't be 1317 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 1318 * attempt to obtain another state object ran into a &drm_modeset_lock 1319 * deadlock. 1320 */ 1321 int (*atomic_check)(struct drm_plane *plane, 1322 struct drm_atomic_state *state); 1323 1324 /** 1325 * @atomic_update: 1326 * 1327 * Drivers should use this function to update the plane state. This 1328 * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and 1329 * drm_crtc_helper_funcs.atomic_flush callbacks. 1330 * 1331 * Note that the power state of the display pipe when this function is 1332 * called depends upon the exact helpers and calling sequence the driver 1333 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 1334 * the tradeoffs and variants of plane commit helpers. 1335 * 1336 * This callback is used by the atomic modeset helpers, but it is optional. 1337 */ 1338 void (*atomic_update)(struct drm_plane *plane, 1339 struct drm_atomic_state *state); 1340 1341 /** 1342 * @atomic_enable: 1343 * 1344 * Drivers should use this function to unconditionally enable a plane. 1345 * This hook is called in-between the &drm_crtc_helper_funcs.atomic_begin 1346 * and drm_crtc_helper_funcs.atomic_flush callbacks. It is called after 1347 * @atomic_update, which will be called for all enabled planes. Drivers 1348 * that use @atomic_enable should set up a plane in @atomic_update and 1349 * afterwards enable the plane in @atomic_enable. If a plane needs to be 1350 * enabled before installing the scanout buffer, drivers can still do 1351 * so in @atomic_update. 1352 * 1353 * Note that the power state of the display pipe when this function is 1354 * called depends upon the exact helpers and calling sequence the driver 1355 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 1356 * the tradeoffs and variants of plane commit helpers. 1357 * 1358 * This callback is used by the atomic modeset helpers, but it is 1359 * optional. If implemented, @atomic_enable should be the inverse of 1360 * @atomic_disable. Drivers that don't want to use either can still 1361 * implement the complete plane update in @atomic_update. 1362 */ 1363 void (*atomic_enable)(struct drm_plane *plane, 1364 struct drm_atomic_state *state); 1365 1366 /** 1367 * @atomic_disable: 1368 * 1369 * Drivers should use this function to unconditionally disable a plane. 1370 * This hook is called in-between the 1371 * &drm_crtc_helper_funcs.atomic_begin and 1372 * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to 1373 * @atomic_update, which will be called for disabling planes, too, if 1374 * the @atomic_disable hook isn't implemented. 1375 * 1376 * This hook is also useful to disable planes in preparation of a modeset, 1377 * by calling drm_atomic_helper_disable_planes_on_crtc() from the 1378 * &drm_crtc_helper_funcs.disable hook. 1379 * 1380 * Note that the power state of the display pipe when this function is 1381 * called depends upon the exact helpers and calling sequence the driver 1382 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 1383 * the tradeoffs and variants of plane commit helpers. 1384 * 1385 * This callback is used by the atomic modeset helpers, but it is 1386 * optional. It's intended to reverse the effects of @atomic_enable. 1387 */ 1388 void (*atomic_disable)(struct drm_plane *plane, 1389 struct drm_atomic_state *state); 1390 1391 /** 1392 * @atomic_async_check: 1393 * 1394 * Drivers should set this function pointer to check if the plane's 1395 * atomic state can be updated in a async fashion. Here async means 1396 * "not vblank synchronized". 1397 * 1398 * This hook is called by drm_atomic_async_check() to establish if a 1399 * given update can be committed asynchronously, that is, if it can 1400 * jump ahead of the state currently queued for update. 1401 * 1402 * RETURNS: 1403 * 1404 * Return 0 on success and any error returned indicates that the update 1405 * can not be applied in asynchronous manner. 1406 */ 1407 int (*atomic_async_check)(struct drm_plane *plane, 1408 struct drm_atomic_state *state); 1409 1410 /** 1411 * @atomic_async_update: 1412 * 1413 * Drivers should set this function pointer to perform asynchronous 1414 * updates of planes, that is, jump ahead of the currently queued 1415 * state and update the plane. Here async means "not vblank 1416 * synchronized". 1417 * 1418 * This hook is called by drm_atomic_helper_async_commit(). 1419 * 1420 * An async update will happen on legacy cursor updates. An async 1421 * update won't happen if there is an outstanding commit modifying 1422 * the same plane. 1423 * 1424 * When doing async_update drivers shouldn't replace the 1425 * &drm_plane_state but update the current one with the new plane 1426 * configurations in the new plane_state. 1427 * 1428 * Drivers should also swap the framebuffers between current plane 1429 * state (&drm_plane.state) and new_state. 1430 * This is required since cleanup for async commits is performed on 1431 * the new state, rather than old state like for traditional commits. 1432 * Since we want to give up the reference on the current (old) fb 1433 * instead of our brand new one, swap them in the driver during the 1434 * async commit. 1435 * 1436 * FIXME: 1437 * - It only works for single plane updates 1438 * - Async Pageflips are not supported yet 1439 * - Some hw might still scan out the old buffer until the next 1440 * vblank, however we let go of the fb references as soon as 1441 * we run this hook. For now drivers must implement their own workers 1442 * for deferring if needed, until a common solution is created. 1443 */ 1444 void (*atomic_async_update)(struct drm_plane *plane, 1445 struct drm_atomic_state *state); 1446}; 1447 1448/** 1449 * drm_plane_helper_add - sets the helper vtable for a plane 1450 * @plane: DRM plane 1451 * @funcs: helper vtable to set for @plane 1452 */ 1453static inline void drm_plane_helper_add(struct drm_plane *plane, 1454 const struct drm_plane_helper_funcs *funcs) 1455{ 1456 plane->helper_private = funcs; 1457} 1458 1459/** 1460 * struct drm_mode_config_helper_funcs - global modeset helper operations 1461 * 1462 * These helper functions are used by the atomic helpers. 1463 */ 1464struct drm_mode_config_helper_funcs { 1465 /** 1466 * @atomic_commit_tail: 1467 * 1468 * This hook is used by the default atomic_commit() hook implemented in 1469 * drm_atomic_helper_commit() together with the nonblocking commit 1470 * helpers (see drm_atomic_helper_setup_commit() for a starting point) 1471 * to implement blocking and nonblocking commits easily. It is not used 1472 * by the atomic helpers 1473 * 1474 * This function is called when the new atomic state has already been 1475 * swapped into the various state pointers. The passed in state 1476 * therefore contains copies of the old/previous state. This hook should 1477 * commit the new state into hardware. Note that the helpers have 1478 * already waited for preceding atomic commits and fences, but drivers 1479 * can add more waiting calls at the start of their implementation, e.g. 1480 * to wait for driver-internal request for implicit syncing, before 1481 * starting to commit the update to the hardware. 1482 * 1483 * After the atomic update is committed to the hardware this hook needs 1484 * to call drm_atomic_helper_commit_hw_done(). Then wait for the update 1485 * to be executed by the hardware, for example using 1486 * drm_atomic_helper_wait_for_vblanks() or 1487 * drm_atomic_helper_wait_for_flip_done(), and then clean up the old 1488 * framebuffers using drm_atomic_helper_cleanup_planes(). 1489 * 1490 * When disabling a CRTC this hook _must_ stall for the commit to 1491 * complete. Vblank waits don't work on disabled CRTC, hence the core 1492 * can't take care of this. And it also can't rely on the vblank event, 1493 * since that can be signalled already when the screen shows black, 1494 * which can happen much earlier than the last hardware access needed to 1495 * shut off the display pipeline completely. 1496 * 1497 * This hook is optional, the default implementation is 1498 * drm_atomic_helper_commit_tail(). 1499 */ 1500 void (*atomic_commit_tail)(struct drm_atomic_state *state); 1501 1502 /** 1503 * @atomic_commit_setup: 1504 * 1505 * This hook is used by the default atomic_commit() hook implemented in 1506 * drm_atomic_helper_commit() together with the nonblocking helpers (see 1507 * drm_atomic_helper_setup_commit()) to extend the DRM commit setup. It 1508 * is not used by the atomic helpers. 1509 * 1510 * This function is called at the end of 1511 * drm_atomic_helper_setup_commit(), so once the commit has been 1512 * properly setup across the generic DRM object states. It allows 1513 * drivers to do some additional commit tracking that isn't related to a 1514 * CRTC, plane or connector, tracked in a &drm_private_obj structure. 1515 * 1516 * Note that the documentation of &drm_private_obj has more details on 1517 * how one should implement this. 1518 * 1519 * This hook is optional. 1520 */ 1521 int (*atomic_commit_setup)(struct drm_atomic_state *state); 1522}; 1523 1524#endif 1525