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 51enum mode_set_atomic; 52 53/** 54 * struct drm_crtc_helper_funcs - helper operations for CRTCs 55 * 56 * These hooks are used by the legacy CRTC helpers, the transitional plane 57 * helpers and the new atomic modesetting helpers. 58 */ 59struct drm_crtc_helper_funcs { 60 /** 61 * @dpms: 62 * 63 * Callback to control power levels on the CRTC. If the mode passed in 64 * is unsupported, the provider must use the next lowest power level. 65 * This is used by the legacy CRTC helpers to implement DPMS 66 * functionality in drm_helper_connector_dpms(). 67 * 68 * This callback is also used to disable a CRTC by calling it with 69 * DRM_MODE_DPMS_OFF if the @disable hook isn't used. 70 * 71 * This callback is used by the legacy CRTC helpers. Atomic helpers 72 * also support using this hook for enabling and disabling a CRTC to 73 * facilitate transitions to atomic, but it is deprecated. Instead 74 * @atomic_enable and @atomic_disable should be used. 75 */ 76 void (*dpms)(struct drm_crtc *crtc, int mode); 77 78 /** 79 * @prepare: 80 * 81 * This callback should prepare the CRTC for a subsequent modeset, which 82 * in practice means the driver should disable the CRTC if it is 83 * running. Most drivers ended up implementing this by calling their 84 * @dpms hook with DRM_MODE_DPMS_OFF. 85 * 86 * This callback is used by the legacy CRTC helpers. Atomic helpers 87 * also support using this hook for disabling a CRTC to facilitate 88 * transitions to atomic, but it is deprecated. Instead @atomic_disable 89 * should be used. 90 */ 91 void (*prepare)(struct drm_crtc *crtc); 92 93 /** 94 * @commit: 95 * 96 * This callback should commit the new mode on the CRTC after a modeset, 97 * which in practice means the driver should enable the CRTC. Most 98 * drivers ended up implementing this by calling their @dpms hook with 99 * DRM_MODE_DPMS_ON. 100 * 101 * This callback is used by the legacy CRTC helpers. Atomic helpers 102 * also support using this hook for enabling a CRTC to facilitate 103 * transitions to atomic, but it is deprecated. Instead @atomic_enable 104 * should be used. 105 */ 106 void (*commit)(struct drm_crtc *crtc); 107 108 /** 109 * @mode_valid: 110 * 111 * This callback is used to check if a specific mode is valid in this 112 * crtc. This should be implemented if the crtc has some sort of 113 * restriction in the modes it can display. For example, a given crtc 114 * may be responsible to set a clock value. If the clock can not 115 * produce all the values for the available modes then this callback 116 * can be used to restrict the number of modes to only the ones that 117 * can be displayed. 118 * 119 * This hook is used by the probe helpers to filter the mode list in 120 * drm_helper_probe_single_connector_modes(), and it is used by the 121 * atomic helpers to validate modes supplied by userspace in 122 * drm_atomic_helper_check_modeset(). 123 * 124 * This function is optional. 125 * 126 * NOTE: 127 * 128 * Since this function is both called from the check phase of an atomic 129 * commit, and the mode validation in the probe paths it is not allowed 130 * to look at anything else but the passed-in mode, and validate it 131 * against configuration-invariant hardward constraints. Any further 132 * limits which depend upon the configuration can only be checked in 133 * @mode_fixup or @atomic_check. 134 * 135 * RETURNS: 136 * 137 * drm_mode_status Enum 138 */ 139 enum drm_mode_status (*mode_valid)(struct drm_crtc *crtc, 140 const struct drm_display_mode *mode); 141 142 /** 143 * @mode_fixup: 144 * 145 * This callback is used to validate a mode. The parameter mode is the 146 * display mode that userspace requested, adjusted_mode is the mode the 147 * encoders need to be fed with. Note that this is the inverse semantics 148 * of the meaning for the &drm_encoder and &drm_bridge_funcs.mode_fixup 149 * vfunc. If the CRTC cannot support the requested conversion from mode 150 * to adjusted_mode it should reject the modeset. See also 151 * &drm_crtc_state.adjusted_mode for more details. 152 * 153 * This function is used by both legacy CRTC helpers and atomic helpers. 154 * With atomic helpers it is optional. 155 * 156 * NOTE: 157 * 158 * This function is called in the check phase of atomic modesets, which 159 * can be aborted for any reason (including on userspace's request to 160 * just check whether a configuration would be possible). Atomic drivers 161 * MUST NOT touch any persistent state (hardware or software) or data 162 * structures except the passed in adjusted_mode parameter. 163 * 164 * This is in contrast to the legacy CRTC helpers where this was 165 * allowed. 166 * 167 * Atomic drivers which need to inspect and adjust more state should 168 * instead use the @atomic_check callback, but note that they're not 169 * perfectly equivalent: @mode_valid is called from 170 * drm_atomic_helper_check_modeset(), but @atomic_check is called from 171 * drm_atomic_helper_check_planes(), because originally it was meant for 172 * plane update checks only. 173 * 174 * Also beware that userspace can request its own custom modes, neither 175 * core nor helpers filter modes to the list of probe modes reported by 176 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 177 * that modes are filtered consistently put any CRTC constraints and 178 * limits checks into @mode_valid. 179 * 180 * RETURNS: 181 * 182 * True if an acceptable configuration is possible, false if the modeset 183 * operation should be rejected. 184 */ 185 bool (*mode_fixup)(struct drm_crtc *crtc, 186 const struct drm_display_mode *mode, 187 struct drm_display_mode *adjusted_mode); 188 189 /** 190 * @mode_set: 191 * 192 * This callback is used by the legacy CRTC helpers to set a new mode, 193 * position and framebuffer. Since it ties the primary plane to every 194 * mode change it is incompatible with universal plane support. And 195 * since it can't update other planes it's incompatible with atomic 196 * modeset support. 197 * 198 * This callback is only used by CRTC helpers and deprecated. 199 * 200 * RETURNS: 201 * 202 * 0 on success or a negative error code on failure. 203 */ 204 int (*mode_set)(struct drm_crtc *crtc, struct drm_display_mode *mode, 205 struct drm_display_mode *adjusted_mode, int x, int y, 206 struct drm_framebuffer *old_fb); 207 208 /** 209 * @mode_set_nofb: 210 * 211 * This callback is used to update the display mode of a CRTC without 212 * changing anything of the primary plane configuration. This fits the 213 * requirement of atomic and hence is used by the atomic helpers. It is 214 * also used by the transitional plane helpers to implement a 215 * @mode_set hook in drm_helper_crtc_mode_set(). 216 * 217 * Note that the display pipe is completely off when this function is 218 * called. Atomic drivers which need hardware to be running before they 219 * program the new display mode (e.g. because they implement runtime PM) 220 * should not use this hook. This is because the helper library calls 221 * this hook only once per mode change and not every time the display 222 * pipeline is suspended using either DPMS or the new "ACTIVE" property. 223 * Which means register values set in this callback might get reset when 224 * the CRTC is suspended, but not restored. Such drivers should instead 225 * move all their CRTC setup into the @atomic_enable callback. 226 * 227 * This callback is optional. 228 */ 229 void (*mode_set_nofb)(struct drm_crtc *crtc); 230 231 /** 232 * @mode_set_base: 233 * 234 * This callback is used by the legacy CRTC helpers to set a new 235 * framebuffer and scanout position. It is optional and used as an 236 * optimized fast-path instead of a full mode set operation with all the 237 * resulting flickering. If it is not present 238 * drm_crtc_helper_set_config() will fall back to a full modeset, using 239 * the @mode_set callback. Since it can't update other planes it's 240 * incompatible with atomic modeset support. 241 * 242 * This callback is only used by the CRTC helpers and deprecated. 243 * 244 * RETURNS: 245 * 246 * 0 on success or a negative error code on failure. 247 */ 248 int (*mode_set_base)(struct drm_crtc *crtc, int x, int y, 249 struct drm_framebuffer *old_fb); 250 251 /** 252 * @mode_set_base_atomic: 253 * 254 * This callback is used by the fbdev helpers to set a new framebuffer 255 * and scanout without sleeping, i.e. from an atomic calling context. It 256 * is only used to implement kgdb support. 257 * 258 * This callback is optional and only needed for kgdb support in the fbdev 259 * helpers. 260 * 261 * RETURNS: 262 * 263 * 0 on success or a negative error code on failure. 264 */ 265 int (*mode_set_base_atomic)(struct drm_crtc *crtc, 266 struct drm_framebuffer *fb, int x, int y, 267 enum mode_set_atomic); 268 269 /** 270 * @disable: 271 * 272 * This callback should be used to disable the CRTC. With the atomic 273 * drivers it is called after all encoders connected to this CRTC have 274 * been shut off already using their own 275 * &drm_encoder_helper_funcs.disable hook. If that sequence is too 276 * simple drivers can just add their own hooks and call it from this 277 * CRTC callback here by looping over all encoders connected to it using 278 * for_each_encoder_on_crtc(). 279 * 280 * This hook is used both by legacy CRTC helpers and atomic helpers. 281 * Atomic drivers don't need to implement it if there's no need to 282 * disable anything at the CRTC level. To ensure that runtime PM 283 * handling (using either DPMS or the new "ACTIVE" property) works 284 * @disable must be the inverse of @atomic_enable for atomic drivers. 285 * Atomic drivers should consider to use @atomic_disable instead of 286 * this one. 287 * 288 * NOTE: 289 * 290 * With legacy CRTC helpers there's a big semantic difference between 291 * @disable and other hooks (like @prepare or @dpms) used to shut down a 292 * CRTC: @disable is only called when also logically disabling the 293 * display pipeline and needs to release any resources acquired in 294 * @mode_set (like shared PLLs, or again release pinned framebuffers). 295 * 296 * Therefore @disable must be the inverse of @mode_set plus @commit for 297 * drivers still using legacy CRTC helpers, which is different from the 298 * rules under atomic. 299 */ 300 void (*disable)(struct drm_crtc *crtc); 301 302 /** 303 * @atomic_check: 304 * 305 * Drivers should check plane-update related CRTC constraints in this 306 * hook. They can also check mode related limitations but need to be 307 * aware of the calling order, since this hook is used by 308 * drm_atomic_helper_check_planes() whereas the preparations needed to 309 * check output routing and the display mode is done in 310 * drm_atomic_helper_check_modeset(). Therefore drivers that want to 311 * check output routing and display mode constraints in this callback 312 * must ensure that drm_atomic_helper_check_modeset() has been called 313 * beforehand. This is calling order used by the default helper 314 * implementation in drm_atomic_helper_check(). 315 * 316 * When using drm_atomic_helper_check_planes() this hook is called 317 * after the &drm_plane_helper_funcs.atomic_check hook for planes, which 318 * allows drivers to assign shared resources requested by planes in this 319 * callback here. For more complicated dependencies the driver can call 320 * the provided check helpers multiple times until the computed state 321 * has a final configuration and everything has been checked. 322 * 323 * This function is also allowed to inspect any other object's state and 324 * can add more state objects to the atomic commit if needed. Care must 325 * be taken though to ensure that state check and compute functions for 326 * these added states are all called, and derived state in other objects 327 * all updated. Again the recommendation is to just call check helpers 328 * until a maximal configuration is reached. 329 * 330 * This callback is used by the atomic modeset helpers and by the 331 * transitional plane helpers, but it is optional. 332 * 333 * NOTE: 334 * 335 * This function is called in the check phase of an atomic update. The 336 * driver is not allowed to change anything outside of the free-standing 337 * state objects passed-in or assembled in the overall &drm_atomic_state 338 * update tracking structure. 339 * 340 * Also beware that userspace can request its own custom modes, neither 341 * core nor helpers filter modes to the list of probe modes reported by 342 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 343 * that modes are filtered consistently put any CRTC constraints and 344 * limits checks into @mode_valid. 345 * 346 * RETURNS: 347 * 348 * 0 on success, -EINVAL if the state or the transition can't be 349 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 350 * attempt to obtain another state object ran into a &drm_modeset_lock 351 * deadlock. 352 */ 353 int (*atomic_check)(struct drm_crtc *crtc, 354 struct drm_crtc_state *state); 355 356 /** 357 * @atomic_begin: 358 * 359 * Drivers should prepare for an atomic update of multiple planes on 360 * a CRTC in this hook. Depending upon hardware this might be vblank 361 * evasion, blocking updates by setting bits or doing preparatory work 362 * for e.g. manual update display. 363 * 364 * This hook is called before any plane commit functions are called. 365 * 366 * Note that the power state of the display pipe when this function is 367 * called depends upon the exact helpers and calling sequence the driver 368 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 369 * the tradeoffs and variants of plane commit helpers. 370 * 371 * This callback is used by the atomic modeset helpers and by the 372 * transitional plane helpers, but it is optional. 373 */ 374 void (*atomic_begin)(struct drm_crtc *crtc, 375 struct drm_crtc_state *old_crtc_state); 376 /** 377 * @atomic_flush: 378 * 379 * Drivers should finalize an atomic update of multiple planes on 380 * a CRTC in this hook. Depending upon hardware this might include 381 * checking that vblank evasion was successful, unblocking updates by 382 * setting bits or setting the GO bit to flush out all updates. 383 * 384 * Simple hardware or hardware with special requirements can commit and 385 * flush out all updates for all planes from this hook and forgo all the 386 * other commit hooks for plane updates. 387 * 388 * This hook is called after any plane commit functions are called. 389 * 390 * Note that the power state of the display pipe when this function is 391 * called depends upon the exact helpers and calling sequence the driver 392 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 393 * the tradeoffs and variants of plane commit helpers. 394 * 395 * This callback is used by the atomic modeset helpers and by the 396 * transitional plane helpers, but it is optional. 397 */ 398 void (*atomic_flush)(struct drm_crtc *crtc, 399 struct drm_crtc_state *old_crtc_state); 400 401 /** 402 * @atomic_enable: 403 * 404 * This callback should be used to enable the CRTC. With the atomic 405 * drivers it is called before all encoders connected to this CRTC are 406 * enabled through the encoder's own &drm_encoder_helper_funcs.enable 407 * hook. If that sequence is too simple drivers can just add their own 408 * hooks and call it from this CRTC callback here by looping over all 409 * encoders connected to it using for_each_encoder_on_crtc(). 410 * 411 * This hook is used only by atomic helpers, for symmetry with 412 * @atomic_disable. Atomic drivers don't need to implement it if there's 413 * no need to enable anything at the CRTC level. To ensure that runtime 414 * PM handling (using either DPMS or the new "ACTIVE" property) works 415 * @atomic_enable must be the inverse of @atomic_disable for atomic 416 * drivers. 417 * 418 * Drivers can use the @old_crtc_state input parameter if the operations 419 * needed to enable the CRTC don't depend solely on the new state but 420 * also on the transition between the old state and the new state. 421 */ 422 void (*atomic_enable)(struct drm_crtc *crtc, 423 struct drm_crtc_state *old_crtc_state); 424 425 /** 426 * @atomic_disable: 427 * 428 * This callback should be used to disable the CRTC. With the atomic 429 * drivers it is called after all encoders connected to this CRTC have 430 * been shut off already using their own 431 * &drm_encoder_helper_funcs.disable hook. If that sequence is too 432 * simple drivers can just add their own hooks and call it from this 433 * CRTC callback here by looping over all encoders connected to it using 434 * for_each_encoder_on_crtc(). 435 * 436 * This hook is used only by atomic helpers. Atomic drivers don't 437 * need to implement it if there's no need to disable anything at the 438 * CRTC level. 439 * 440 * Comparing to @disable, this one provides the additional input 441 * parameter @old_crtc_state which could be used to access the old 442 * state. Atomic drivers should consider to use this one instead 443 * of @disable. 444 */ 445 void (*atomic_disable)(struct drm_crtc *crtc, 446 struct drm_crtc_state *old_crtc_state); 447}; 448 449/** 450 * drm_crtc_helper_add - sets the helper vtable for a crtc 451 * @crtc: DRM CRTC 452 * @funcs: helper vtable to set for @crtc 453 */ 454static inline void drm_crtc_helper_add(struct drm_crtc *crtc, 455 const struct drm_crtc_helper_funcs *funcs) 456{ 457 crtc->helper_private = funcs; 458} 459 460/** 461 * struct drm_encoder_helper_funcs - helper operations for encoders 462 * 463 * These hooks are used by the legacy CRTC helpers, the transitional plane 464 * helpers and the new atomic modesetting helpers. 465 */ 466struct drm_encoder_helper_funcs { 467 /** 468 * @dpms: 469 * 470 * Callback to control power levels on the encoder. If the mode passed in 471 * is unsupported, the provider must use the next lowest power level. 472 * This is used by the legacy encoder helpers to implement DPMS 473 * functionality in drm_helper_connector_dpms(). 474 * 475 * This callback is also used to disable an encoder by calling it with 476 * DRM_MODE_DPMS_OFF if the @disable hook isn't used. 477 * 478 * This callback is used by the legacy CRTC helpers. Atomic helpers 479 * also support using this hook for enabling and disabling an encoder to 480 * facilitate transitions to atomic, but it is deprecated. Instead 481 * @enable and @disable should be used. 482 */ 483 void (*dpms)(struct drm_encoder *encoder, int mode); 484 485 /** 486 * @mode_valid: 487 * 488 * This callback is used to check if a specific mode is valid in this 489 * encoder. This should be implemented if the encoder has some sort 490 * of restriction in the modes it can display. For example, a given 491 * encoder may be responsible to set a clock value. If the clock can 492 * not produce all the values for the available modes then this callback 493 * can be used to restrict the number of modes to only the ones that 494 * can be displayed. 495 * 496 * This hook is used by the probe helpers to filter the mode list in 497 * drm_helper_probe_single_connector_modes(), and it is used by the 498 * atomic helpers to validate modes supplied by userspace in 499 * drm_atomic_helper_check_modeset(). 500 * 501 * This function is optional. 502 * 503 * NOTE: 504 * 505 * Since this function is both called from the check phase of an atomic 506 * commit, and the mode validation in the probe paths it is not allowed 507 * to look at anything else but the passed-in mode, and validate it 508 * against configuration-invariant hardward constraints. Any further 509 * limits which depend upon the configuration can only be checked in 510 * @mode_fixup or @atomic_check. 511 * 512 * RETURNS: 513 * 514 * drm_mode_status Enum 515 */ 516 enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc, 517 const struct drm_display_mode *mode); 518 519 /** 520 * @mode_fixup: 521 * 522 * This callback is used to validate and adjust a mode. The parameter 523 * mode is the display mode that should be fed to the next element in 524 * the display chain, either the final &drm_connector or a &drm_bridge. 525 * The parameter adjusted_mode is the input mode the encoder requires. It 526 * can be modified by this callback and does not need to match mode. See 527 * also &drm_crtc_state.adjusted_mode for more details. 528 * 529 * This function is used by both legacy CRTC helpers and atomic helpers. 530 * This hook is optional. 531 * 532 * NOTE: 533 * 534 * This function is called in the check phase of atomic modesets, which 535 * can be aborted for any reason (including on userspace's request to 536 * just check whether a configuration would be possible). Atomic drivers 537 * MUST NOT touch any persistent state (hardware or software) or data 538 * structures except the passed in adjusted_mode parameter. 539 * 540 * This is in contrast to the legacy CRTC helpers where this was 541 * allowed. 542 * 543 * Atomic drivers which need to inspect and adjust more state should 544 * instead use the @atomic_check callback. If @atomic_check is used, 545 * this hook isn't called since @atomic_check allows a strict superset 546 * of the functionality of @mode_fixup. 547 * 548 * Also beware that userspace can request its own custom modes, neither 549 * core nor helpers filter modes to the list of probe modes reported by 550 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 551 * that modes are filtered consistently put any encoder constraints and 552 * limits checks into @mode_valid. 553 * 554 * RETURNS: 555 * 556 * True if an acceptable configuration is possible, false if the modeset 557 * operation should be rejected. 558 */ 559 bool (*mode_fixup)(struct drm_encoder *encoder, 560 const struct drm_display_mode *mode, 561 struct drm_display_mode *adjusted_mode); 562 563 /** 564 * @prepare: 565 * 566 * This callback should prepare the encoder for a subsequent modeset, 567 * which in practice means the driver should disable the encoder if it 568 * is running. Most drivers ended up implementing this by calling their 569 * @dpms hook with DRM_MODE_DPMS_OFF. 570 * 571 * This callback is used by the legacy CRTC helpers. Atomic helpers 572 * also support using this hook for disabling an encoder to facilitate 573 * transitions to atomic, but it is deprecated. Instead @disable should 574 * be used. 575 */ 576 void (*prepare)(struct drm_encoder *encoder); 577 578 /** 579 * @commit: 580 * 581 * This callback should commit the new mode on the encoder after a modeset, 582 * which in practice means the driver should enable the encoder. Most 583 * drivers ended up implementing this by calling their @dpms hook with 584 * DRM_MODE_DPMS_ON. 585 * 586 * This callback is used by the legacy CRTC helpers. Atomic helpers 587 * also support using this hook for enabling an encoder to facilitate 588 * transitions to atomic, but it is deprecated. Instead @enable should 589 * be used. 590 */ 591 void (*commit)(struct drm_encoder *encoder); 592 593 /** 594 * @mode_set: 595 * 596 * This callback is used to update the display mode of an encoder. 597 * 598 * Note that the display pipe is completely off when this function is 599 * called. Drivers which need hardware to be running before they program 600 * the new display mode (because they implement runtime PM) should not 601 * use this hook, because the helper library calls it only once and not 602 * every time the display pipeline is suspend using either DPMS or the 603 * new "ACTIVE" property. Such drivers should instead move all their 604 * encoder setup into the @enable callback. 605 * 606 * This callback is used both by the legacy CRTC helpers and the atomic 607 * modeset helpers. It is optional in the atomic helpers. 608 * 609 * NOTE: 610 * 611 * If the driver uses the atomic modeset helpers and needs to inspect 612 * the connector state or connector display info during mode setting, 613 * @atomic_mode_set can be used instead. 614 */ 615 void (*mode_set)(struct drm_encoder *encoder, 616 struct drm_display_mode *mode, 617 struct drm_display_mode *adjusted_mode); 618 619 /** 620 * @atomic_mode_set: 621 * 622 * This callback is used to update the display mode of an encoder. 623 * 624 * Note that the display pipe is completely off when this function is 625 * called. Drivers which need hardware to be running before they program 626 * the new display mode (because they implement runtime PM) should not 627 * use this hook, because the helper library calls it only once and not 628 * every time the display pipeline is suspended using either DPMS or the 629 * new "ACTIVE" property. Such drivers should instead move all their 630 * encoder setup into the @enable callback. 631 * 632 * This callback is used by the atomic modeset helpers in place of the 633 * @mode_set callback, if set by the driver. It is optional and should 634 * be used instead of @mode_set if the driver needs to inspect the 635 * connector state or display info, since there is no direct way to 636 * go from the encoder to the current connector. 637 */ 638 void (*atomic_mode_set)(struct drm_encoder *encoder, 639 struct drm_crtc_state *crtc_state, 640 struct drm_connector_state *conn_state); 641 642 /** 643 * @get_crtc: 644 * 645 * This callback is used by the legacy CRTC helpers to work around 646 * deficiencies in its own book-keeping. 647 * 648 * Do not use, use atomic helpers instead, which get the book keeping 649 * right. 650 * 651 * FIXME: 652 * 653 * Currently only nouveau is using this, and as soon as nouveau is 654 * atomic we can ditch this hook. 655 */ 656 struct drm_crtc *(*get_crtc)(struct drm_encoder *encoder); 657 658 /** 659 * @detect: 660 * 661 * This callback can be used by drivers who want to do detection on the 662 * encoder object instead of in connector functions. 663 * 664 * It is not used by any helper and therefore has purely driver-specific 665 * semantics. New drivers shouldn't use this and instead just implement 666 * their own private callbacks. 667 * 668 * FIXME: 669 * 670 * This should just be converted into a pile of driver vfuncs. 671 * Currently radeon, amdgpu and nouveau are using it. 672 */ 673 enum drm_connector_status (*detect)(struct drm_encoder *encoder, 674 struct drm_connector *connector); 675 676 /** 677 * @disable: 678 * 679 * This callback should be used to disable the encoder. With the atomic 680 * drivers it is called before this encoder's CRTC has been shut off 681 * using their own &drm_crtc_helper_funcs.disable hook. If that 682 * sequence is too simple drivers can just add their own driver private 683 * encoder hooks and call them from CRTC's callback by looping over all 684 * encoders connected to it using for_each_encoder_on_crtc(). 685 * 686 * This hook is used both by legacy CRTC helpers and atomic helpers. 687 * Atomic drivers don't need to implement it if there's no need to 688 * disable anything at the encoder level. To ensure that runtime PM 689 * handling (using either DPMS or the new "ACTIVE" property) works 690 * @disable must be the inverse of @enable for atomic drivers. 691 * 692 * NOTE: 693 * 694 * With legacy CRTC helpers there's a big semantic difference between 695 * @disable and other hooks (like @prepare or @dpms) used to shut down a 696 * encoder: @disable is only called when also logically disabling the 697 * display pipeline and needs to release any resources acquired in 698 * @mode_set (like shared PLLs, or again release pinned framebuffers). 699 * 700 * Therefore @disable must be the inverse of @mode_set plus @commit for 701 * drivers still using legacy CRTC helpers, which is different from the 702 * rules under atomic. 703 */ 704 void (*disable)(struct drm_encoder *encoder); 705 706 /** 707 * @enable: 708 * 709 * This callback should be used to enable the encoder. With the atomic 710 * drivers it is called after this encoder's CRTC has been enabled using 711 * their own &drm_crtc_helper_funcs.enable hook. If that sequence is 712 * too simple drivers can just add their own driver private encoder 713 * hooks and call them from CRTC's callback by looping over all encoders 714 * connected to it using for_each_encoder_on_crtc(). 715 * 716 * This hook is used only by atomic helpers, for symmetry with @disable. 717 * Atomic drivers don't need to implement it if there's no need to 718 * enable anything at the encoder level. To ensure that runtime PM handling 719 * (using either DPMS or the new "ACTIVE" property) works 720 * @enable must be the inverse of @disable for atomic drivers. 721 */ 722 void (*enable)(struct drm_encoder *encoder); 723 724 /** 725 * @atomic_check: 726 * 727 * This callback is used to validate encoder state for atomic drivers. 728 * Since the encoder is the object connecting the CRTC and connector it 729 * gets passed both states, to be able to validate interactions and 730 * update the CRTC to match what the encoder needs for the requested 731 * connector. 732 * 733 * Since this provides a strict superset of the functionality of 734 * @mode_fixup (the requested and adjusted modes are both available 735 * through the passed in &struct drm_crtc_state) @mode_fixup is not 736 * called when @atomic_check is implemented. 737 * 738 * This function is used by the atomic helpers, but it is optional. 739 * 740 * NOTE: 741 * 742 * This function is called in the check phase of an atomic update. The 743 * driver is not allowed to change anything outside of the free-standing 744 * state objects passed-in or assembled in the overall &drm_atomic_state 745 * update tracking structure. 746 * 747 * Also beware that userspace can request its own custom modes, neither 748 * core nor helpers filter modes to the list of probe modes reported by 749 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 750 * that modes are filtered consistently put any encoder constraints and 751 * limits checks into @mode_valid. 752 * 753 * RETURNS: 754 * 755 * 0 on success, -EINVAL if the state or the transition can't be 756 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 757 * attempt to obtain another state object ran into a &drm_modeset_lock 758 * deadlock. 759 */ 760 int (*atomic_check)(struct drm_encoder *encoder, 761 struct drm_crtc_state *crtc_state, 762 struct drm_connector_state *conn_state); 763}; 764 765/** 766 * drm_encoder_helper_add - sets the helper vtable for an encoder 767 * @encoder: DRM encoder 768 * @funcs: helper vtable to set for @encoder 769 */ 770static inline void drm_encoder_helper_add(struct drm_encoder *encoder, 771 const struct drm_encoder_helper_funcs *funcs) 772{ 773 encoder->helper_private = funcs; 774} 775 776/** 777 * struct drm_connector_helper_funcs - helper operations for connectors 778 * 779 * These functions are used by the atomic and legacy modeset helpers and by the 780 * probe helpers. 781 */ 782struct drm_connector_helper_funcs { 783 /** 784 * @get_modes: 785 * 786 * This function should fill in all modes currently valid for the sink 787 * into the &drm_connector.probed_modes list. It should also update the 788 * EDID property by calling drm_mode_connector_update_edid_property(). 789 * 790 * The usual way to implement this is to cache the EDID retrieved in the 791 * probe callback somewhere in the driver-private connector structure. 792 * In this function drivers then parse the modes in the EDID and add 793 * them by calling drm_add_edid_modes(). But connectors that driver a 794 * fixed panel can also manually add specific modes using 795 * drm_mode_probed_add(). Drivers which manually add modes should also 796 * make sure that the &drm_connector.display_info, 797 * &drm_connector.width_mm and &drm_connector.height_mm fields are 798 * filled in. 799 * 800 * Virtual drivers that just want some standard VESA mode with a given 801 * resolution can call drm_add_modes_noedid(), and mark the preferred 802 * one using drm_set_preferred_mode(). 803 * 804 * This function is only called after the @detect hook has indicated 805 * that a sink is connected and when the EDID isn't overridden through 806 * sysfs or the kernel commandline. 807 * 808 * This callback is used by the probe helpers in e.g. 809 * drm_helper_probe_single_connector_modes(). 810 * 811 * To avoid races with concurrent connector state updates, the helper 812 * libraries always call this with the &drm_mode_config.connection_mutex 813 * held. Because of this it's safe to inspect &drm_connector->state. 814 * 815 * RETURNS: 816 * 817 * The number of modes added by calling drm_mode_probed_add(). 818 */ 819 int (*get_modes)(struct drm_connector *connector); 820 821 /** 822 * @detect_ctx: 823 * 824 * Check to see if anything is attached to the connector. The parameter 825 * force is set to false whilst polling, true when checking the 826 * connector due to a user request. force can be used by the driver to 827 * avoid expensive, destructive operations during automated probing. 828 * 829 * This callback is optional, if not implemented the connector will be 830 * considered as always being attached. 831 * 832 * This is the atomic version of &drm_connector_funcs.detect. 833 * 834 * To avoid races against concurrent connector state updates, the 835 * helper libraries always call this with ctx set to a valid context, 836 * and &drm_mode_config.connection_mutex will always be locked with 837 * the ctx parameter set to this ctx. This allows taking additional 838 * locks as required. 839 * 840 * RETURNS: 841 * 842 * &drm_connector_status indicating the connector's status, 843 * or the error code returned by drm_modeset_lock(), -EDEADLK. 844 */ 845 int (*detect_ctx)(struct drm_connector *connector, 846 struct drm_modeset_acquire_ctx *ctx, 847 bool force); 848 849 /** 850 * @mode_valid: 851 * 852 * Callback to validate a mode for a connector, irrespective of the 853 * specific display configuration. 854 * 855 * This callback is used by the probe helpers to filter the mode list 856 * (which is usually derived from the EDID data block from the sink). 857 * See e.g. drm_helper_probe_single_connector_modes(). 858 * 859 * This function is optional. 860 * 861 * NOTE: 862 * 863 * This only filters the mode list supplied to userspace in the 864 * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid, 865 * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid, 866 * which are also called by the atomic helpers from 867 * drm_atomic_helper_check_modeset(). This allows userspace to force and 868 * ignore sink constraint (like the pixel clock limits in the screen's 869 * EDID), which is useful for e.g. testing, or working around a broken 870 * EDID. Any source hardware constraint (which always need to be 871 * enforced) therefore should be checked in one of the above callbacks, 872 * and not this one here. 873 * 874 * To avoid races with concurrent connector state updates, the helper 875 * libraries always call this with the &drm_mode_config.connection_mutex 876 * held. Because of this it's safe to inspect &drm_connector->state. 877 * 878 * RETURNS: 879 * 880 * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum 881 * drm_mode_status. 882 */ 883 enum drm_mode_status (*mode_valid)(struct drm_connector *connector, 884 struct drm_display_mode *mode); 885 /** 886 * @best_encoder: 887 * 888 * This function should select the best encoder for the given connector. 889 * 890 * This function is used by both the atomic helpers (in the 891 * drm_atomic_helper_check_modeset() function) and in the legacy CRTC 892 * helpers. 893 * 894 * NOTE: 895 * 896 * In atomic drivers this function is called in the check phase of an 897 * atomic update. The driver is not allowed to change or inspect 898 * anything outside of arguments passed-in. Atomic drivers which need to 899 * inspect dynamic configuration state should instead use 900 * @atomic_best_encoder. 901 * 902 * You can leave this function to NULL if the connector is only 903 * attached to a single encoder and you are using the atomic helpers. 904 * In this case, the core will call drm_atomic_helper_best_encoder() 905 * for you. 906 * 907 * RETURNS: 908 * 909 * Encoder that should be used for the given connector and connector 910 * state, or NULL if no suitable encoder exists. Note that the helpers 911 * will ensure that encoders aren't used twice, drivers should not check 912 * for this. 913 */ 914 struct drm_encoder *(*best_encoder)(struct drm_connector *connector); 915 916 /** 917 * @atomic_best_encoder: 918 * 919 * This is the atomic version of @best_encoder for atomic drivers which 920 * need to select the best encoder depending upon the desired 921 * configuration and can't select it statically. 922 * 923 * This function is used by drm_atomic_helper_check_modeset(). 924 * If it is not implemented, the core will fallback to @best_encoder 925 * (or drm_atomic_helper_best_encoder() if @best_encoder is NULL). 926 * 927 * NOTE: 928 * 929 * This function is called in the check phase of an atomic update. The 930 * driver is not allowed to change anything outside of the free-standing 931 * state objects passed-in or assembled in the overall &drm_atomic_state 932 * update tracking structure. 933 * 934 * RETURNS: 935 * 936 * Encoder that should be used for the given connector and connector 937 * state, or NULL if no suitable encoder exists. Note that the helpers 938 * will ensure that encoders aren't used twice, drivers should not check 939 * for this. 940 */ 941 struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector, 942 struct drm_connector_state *connector_state); 943 944 /** 945 * @atomic_check: 946 * 947 * This hook is used to validate connector state. This function is 948 * called from &drm_atomic_helper_check_modeset, and is called when 949 * a connector property is set, or a modeset on the crtc is forced. 950 * 951 * Because &drm_atomic_helper_check_modeset may be called multiple times, 952 * this function should handle being called multiple times as well. 953 * 954 * This function is also allowed to inspect any other object's state and 955 * can add more state objects to the atomic commit if needed. Care must 956 * be taken though to ensure that state check and compute functions for 957 * these added states are all called, and derived state in other objects 958 * all updated. Again the recommendation is to just call check helpers 959 * until a maximal configuration is reached. 960 * 961 * NOTE: 962 * 963 * This function is called in the check phase of an atomic update. The 964 * driver is not allowed to change anything outside of the free-standing 965 * state objects passed-in or assembled in the overall &drm_atomic_state 966 * update tracking structure. 967 * 968 * RETURNS: 969 * 970 * 0 on success, -EINVAL if the state or the transition can't be 971 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 972 * attempt to obtain another state object ran into a &drm_modeset_lock 973 * deadlock. 974 */ 975 int (*atomic_check)(struct drm_connector *connector, 976 struct drm_connector_state *state); 977}; 978 979/** 980 * drm_connector_helper_add - sets the helper vtable for a connector 981 * @connector: DRM connector 982 * @funcs: helper vtable to set for @connector 983 */ 984static inline void drm_connector_helper_add(struct drm_connector *connector, 985 const struct drm_connector_helper_funcs *funcs) 986{ 987 connector->helper_private = funcs; 988} 989 990/** 991 * struct drm_plane_helper_funcs - helper operations for planes 992 * 993 * These functions are used by the atomic helpers and by the transitional plane 994 * helpers. 995 */ 996struct drm_plane_helper_funcs { 997 /** 998 * @prepare_fb: 999 * 1000 * This hook is to prepare a framebuffer for scanout by e.g. pinning
1001 * it's backing storage or relocating it into a contiguous block of 1002 * VRAM. Other possible preparatory work includes flushing caches. 1003 * 1004 * This function must not block for outstanding rendering, since it is 1005 * called in the context of the atomic IOCTL even for async commits to 1006 * be able to return any errors to userspace. Instead the recommended 1007 * way is to fill out the fence member of the passed-in 1008 * &drm_plane_state. If the driver doesn't support native fences then 1009 * equivalent functionality should be implemented through private 1010 * members in the plane structure. 1011 * 1012 * The helpers will call @cleanup_fb with matching arguments for every 1013 * successful call to this hook. 1014 * 1015 * This callback is used by the atomic modeset helpers and by the 1016 * transitional plane helpers, but it is optional. 1017 * 1018 * RETURNS: 1019 * 1020 * 0 on success or one of the following negative error codes allowed by 1021 * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers 1022 * this callback is the only one which can fail an atomic commit, 1023 * everything else must complete successfully. 1024 */ 1025 int (*prepare_fb)(struct drm_plane *plane, 1026 struct drm_plane_state *new_state); 1027 /** 1028 * @cleanup_fb: 1029 * 1030 * This hook is called to clean up any resources allocated for the given 1031 * framebuffer and plane configuration in @prepare_fb. 1032 * 1033 * This callback is used by the atomic modeset helpers and by the 1034 * transitional plane helpers, but it is optional. 1035 */ 1036 void (*cleanup_fb)(struct drm_plane *plane, 1037 struct drm_plane_state *old_state); 1038 1039 /** 1040 * @atomic_check: 1041 * 1042 * Drivers should check plane specific constraints in this hook. 1043 * 1044 * When using drm_atomic_helper_check_planes() plane's @atomic_check 1045 * hooks are called before the ones for CRTCs, which allows drivers to 1046 * request shared resources that the CRTC controls here. For more 1047 * complicated dependencies the driver can call the provided check helpers 1048 * multiple times until the computed state has a final configuration and 1049 * everything has been checked. 1050 * 1051 * This function is also allowed to inspect any other object's state and 1052 * can add more state objects to the atomic commit if needed. Care must 1053 * be taken though to ensure that state check and compute functions for 1054 * these added states are all called, and derived state in other objects 1055 * all updated. Again the recommendation is to just call check helpers 1056 * until a maximal configuration is reached. 1057 * 1058 * This callback is used by the atomic modeset helpers and by the 1059 * transitional plane helpers, but it is optional. 1060 * 1061 * NOTE: 1062 * 1063 * This function is called in the check phase of an atomic update. The 1064 * driver is not allowed to change anything outside of the free-standing 1065 * state objects passed-in or assembled in the overall &drm_atomic_state 1066 * update tracking structure. 1067 * 1068 * RETURNS: 1069 * 1070 * 0 on success, -EINVAL if the state or the transition can't be 1071 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 1072 * attempt to obtain another state object ran into a &drm_modeset_lock 1073 * deadlock. 1074 */ 1075 int (*atomic_check)(struct drm_plane *plane, 1076 struct drm_plane_state *state); 1077 1078 /** 1079 * @atomic_update: 1080 * 1081 * Drivers should use this function to update the plane state. This 1082 * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and 1083 * drm_crtc_helper_funcs.atomic_flush callbacks. 1084 * 1085 * Note that the power state of the display pipe when this function is 1086 * called depends upon the exact helpers and calling sequence the driver 1087 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 1088 * the tradeoffs and variants of plane commit helpers. 1089 * 1090 * This callback is used by the atomic modeset helpers and by the 1091 * transitional plane helpers, but it is optional. 1092 */ 1093 void (*atomic_update)(struct drm_plane *plane, 1094 struct drm_plane_state *old_state); 1095 /** 1096 * @atomic_disable: 1097 * 1098 * Drivers should use this function to unconditionally disable a plane. 1099 * This hook is called in-between the 1100 * &drm_crtc_helper_funcs.atomic_begin and 1101 * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to 1102 * @atomic_update, which will be called for disabling planes, too, if 1103 * the @atomic_disable hook isn't implemented. 1104 * 1105 * This hook is also useful to disable planes in preparation of a modeset, 1106 * by calling drm_atomic_helper_disable_planes_on_crtc() from the 1107 * &drm_crtc_helper_funcs.disable hook. 1108 * 1109 * Note that the power state of the display pipe when this function is 1110 * called depends upon the exact helpers and calling sequence the driver 1111 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 1112 * the tradeoffs and variants of plane commit helpers. 1113 * 1114 * This callback is used by the atomic modeset helpers and by the 1115 * transitional plane helpers, but it is optional. 1116 */ 1117 void (*atomic_disable)(struct drm_plane *plane, 1118 struct drm_plane_state *old_state); 1119 1120 /** 1121 * @atomic_async_check: 1122 * 1123 * Drivers should set this function pointer to check if the plane state 1124 * can be updated in a async fashion. Here async means "not vblank 1125 * synchronized". 1126 * 1127 * This hook is called by drm_atomic_async_check() to establish if a 1128 * given update can be committed asynchronously, that is, if it can 1129 * jump ahead of the state currently queued for update. 1130 * 1131 * RETURNS: 1132 * 1133 * Return 0 on success and any error returned indicates that the update 1134 * can not be applied in asynchronous manner. 1135 */ 1136 int (*atomic_async_check)(struct drm_plane *plane, 1137 struct drm_plane_state *state); 1138 1139 /** 1140 * @atomic_async_update: 1141 * 1142 * Drivers should set this function pointer to perform asynchronous 1143 * updates of planes, that is, jump ahead of the currently queued 1144 * state and update the plane. Here async means "not vblank 1145 * synchronized". 1146 * 1147 * This hook is called by drm_atomic_helper_async_commit(). 1148 * 1149 * An async update will happen on legacy cursor updates. An async 1150 * update won't happen if there is an outstanding commit modifying 1151 * the same plane. 1152 * 1153 * Note that unlike &drm_plane_helper_funcs.atomic_update this hook 1154 * takes the new &drm_plane_state as parameter. When doing async_update 1155 * drivers shouldn't replace the &drm_plane_state but update the 1156 * current one with the new plane configurations in the new 1157 * plane_state. 1158 * 1159 * FIXME: 1160 * - It only works for single plane updates 1161 * - Async Pageflips are not supported yet 1162 * - Some hw might still scan out the old buffer until the next 1163 * vblank, however we let go of the fb references as soon as 1164 * we run this hook. For now drivers must implement their own workers 1165 * for deferring if needed, until a common solution is created. 1166 */ 1167 void (*atomic_async_update)(struct drm_plane *plane, 1168 struct drm_plane_state *new_state); 1169}; 1170 1171/** 1172 * drm_plane_helper_add - sets the helper vtable for a plane 1173 * @plane: DRM plane 1174 * @funcs: helper vtable to set for @plane 1175 */ 1176static inline void drm_plane_helper_add(struct drm_plane *plane, 1177 const struct drm_plane_helper_funcs *funcs) 1178{ 1179 plane->helper_private = funcs; 1180} 1181 1182/** 1183 * struct drm_mode_config_helper_funcs - global modeset helper operations 1184 * 1185 * These helper functions are used by the atomic helpers. 1186 */ 1187struct drm_mode_config_helper_funcs { 1188 /** 1189 * @atomic_commit_tail: 1190 * 1191 * This hook is used by the default atomic_commit() hook implemented in 1192 * drm_atomic_helper_commit() together with the nonblocking commit 1193 * helpers (see drm_atomic_helper_setup_commit() for a starting point) 1194 * to implement blocking and nonblocking commits easily. It is not used 1195 * by the atomic helpers 1196 * 1197 * This function is called when the new atomic state has already been 1198 * swapped into the various state pointers. The passed in state 1199 * therefore contains copies of the old/previous state. This hook should 1200 * commit the new state into hardware. Note that the helpers have 1201 * already waited for preceeding atomic commits and fences, but drivers 1202 * can add more waiting calls at the start of their implementation, e.g. 1203 * to wait for driver-internal request for implicit syncing, before 1204 * starting to commit the update to the hardware. 1205 * 1206 * After the atomic update is committed to the hardware this hook needs 1207 * to call drm_atomic_helper_commit_hw_done(). Then wait for the upate 1208 * to be executed by the hardware, for example using 1209 * drm_atomic_helper_wait_for_vblanks() or 1210 * drm_atomic_helper_wait_for_flip_done(), and then clean up the old 1211 * framebuffers using drm_atomic_helper_cleanup_planes(). 1212 * 1213 * When disabling a CRTC this hook _must_ stall for the commit to 1214 * complete. Vblank waits don't work on disabled CRTC, hence the core 1215 * can't take care of this. And it also can't rely on the vblank event, 1216 * since that can be signalled already when the screen shows black, 1217 * which can happen much earlier than the last hardware access needed to 1218 * shut off the display pipeline completely. 1219 * 1220 * This hook is optional, the default implementation is 1221 * drm_atomic_helper_commit_tail(). 1222 */ 1223 void (*atomic_commit_tail)(struct drm_atomic_state *state); 1224}; 1225 1226#endif 1227