1 /* 2 * Copyright © 2006 Keith Packard 3 * Copyright © 2007-2008 Dave Airlie 4 * Copyright © 2007-2008 Intel Corporation 5 * Jesse Barnes <jesse.barnes@intel.com> 6 * Copyright © 2011-2013 Intel Corporation 7 * Copyright © 2015 Intel Corporation 8 * Daniel Vetter <daniel.vetter@ffwll.ch> 9 * 10 * Permission is hereby granted, free of charge, to any person obtaining a 11 * copy of this software and associated documentation files (the "Software"), 12 * to deal in the Software without restriction, including without limitation 13 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 14 * and/or sell copies of the Software, and to permit persons to whom the 15 * Software is furnished to do so, subject to the following conditions: 16 * 17 * The above copyright notice and this permission notice shall be included in 18 * all copies or substantial portions of the Software. 19 * 20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 23 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 24 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 25 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 26 * OTHER DEALINGS IN THE SOFTWARE. 27 */ 28 29 #ifndef __DRM_MODESET_HELPER_VTABLES_H__ 30 #define __DRM_MODESET_HELPER_VTABLES_H__ 31 32 #include <drm/drm_crtc.h> 33 #include <drm/drm_encoder.h> 34 35 /** 36 * DOC: overview 37 * 38 * The DRM mode setting helper functions are common code for drivers to use if 39 * they wish. Drivers are not forced to use this code in their 40 * implementations but it would be useful if the code they do use at least 41 * provides a consistent interface and operation to userspace. Therefore it is 42 * highly recommended to use the provided helpers as much as possible. 43 * 44 * Because there is only one pointer per modeset object to hold a vfunc table 45 * for helper libraries they are by necessity shared among the different 46 * helpers. 47 * 48 * To make this clear all the helper vtables are pulled together in this location here. 49 */ 50 51 enum mode_set_atomic; 52 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 */ 59 struct 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 * @enable and @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 @disable should 89 * 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 @enable should 104 * 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 @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 * @load_lut: 271 * 272 * Load a LUT prepared with the &drm_fb_helper_funcs.gamma_set vfunc. 273 * 274 * This callback is optional and is only used by the fbdev emulation 275 * helpers. 276 * 277 * FIXME: 278 * 279 * This callback is functionally redundant with the core gamma table 280 * support and simply exists because the fbdev hasn't yet been 281 * refactored to use the core gamma table interfaces. 282 */ 283 void (*load_lut)(struct drm_crtc *crtc); 284 285 /** 286 * @disable: 287 * 288 * This callback should be used to disable the CRTC. With the atomic 289 * drivers it is called after all encoders connected to this CRTC have 290 * been shut off already using their own 291 * &drm_encoder_helper_funcs.disable hook. If that sequence is too 292 * simple drivers can just add their own hooks and call it from this 293 * CRTC callback here by looping over all encoders connected to it using 294 * for_each_encoder_on_crtc(). 295 * 296 * This hook is used both by legacy CRTC helpers and atomic helpers. 297 * Atomic drivers don't need to implement it if there's no need to 298 * disable anything at the CRTC level. To ensure that runtime PM 299 * handling (using either DPMS or the new "ACTIVE" property) works 300 * @disable must be the inverse of @enable for atomic drivers. 301 * Atomic drivers should consider to use @atomic_disable instead of 302 * this one. 303 * 304 * NOTE: 305 * 306 * With legacy CRTC helpers there's a big semantic difference between 307 * @disable and other hooks (like @prepare or @dpms) used to shut down a 308 * CRTC: @disable is only called when also logically disabling the 309 * display pipeline and needs to release any resources acquired in 310 * @mode_set (like shared PLLs, or again release pinned framebuffers). 311 * 312 * Therefore @disable must be the inverse of @mode_set plus @commit for 313 * drivers still using legacy CRTC helpers, which is different from the 314 * rules under atomic. 315 */ 316 void (*disable)(struct drm_crtc *crtc); 317 318 /** 319 * @enable: 320 * 321 * This callback should be used to enable the CRTC. With the atomic 322 * drivers it is called before all encoders connected to this CRTC are 323 * enabled through the encoder's own &drm_encoder_helper_funcs.enable 324 * hook. If that sequence is too simple drivers can just add their own 325 * hooks and call it from this CRTC callback here by looping over all 326 * encoders connected to it using for_each_encoder_on_crtc(). 327 * 328 * This hook is used only by atomic helpers, for symmetry with @disable. 329 * Atomic drivers don't need to implement it if there's no need to 330 * enable anything at the CRTC level. To ensure that runtime PM handling 331 * (using either DPMS or the new "ACTIVE" property) works 332 * @enable must be the inverse of @disable for atomic drivers. 333 */ 334 void (*enable)(struct drm_crtc *crtc); 335 336 /** 337 * @atomic_check: 338 * 339 * Drivers should check plane-update related CRTC constraints in this 340 * hook. They can also check mode related limitations but need to be 341 * aware of the calling order, since this hook is used by 342 * drm_atomic_helper_check_planes() whereas the preparations needed to 343 * check output routing and the display mode is done in 344 * drm_atomic_helper_check_modeset(). Therefore drivers that want to 345 * check output routing and display mode constraints in this callback 346 * must ensure that drm_atomic_helper_check_modeset() has been called 347 * beforehand. This is calling order used by the default helper 348 * implementation in drm_atomic_helper_check(). 349 * 350 * When using drm_atomic_helper_check_planes() this hook is called 351 * after the &drm_plane_helper_funcs.atomc_check hook for planes, which 352 * allows drivers to assign shared resources requested by planes in this 353 * callback here. For more complicated dependencies the driver can call 354 * the provided check helpers multiple times until the computed state 355 * has a final configuration and everything has been checked. 356 * 357 * This function is also allowed to inspect any other object's state and 358 * can add more state objects to the atomic commit if needed. Care must 359 * be taken though to ensure that state check and compute functions for 360 * these added states are all called, and derived state in other objects 361 * all updated. Again the recommendation is to just call check helpers 362 * until a maximal configuration is reached. 363 * 364 * This callback is used by the atomic modeset helpers and by the 365 * transitional plane helpers, but it is optional. 366 * 367 * NOTE: 368 * 369 * This function is called in the check phase of an atomic update. The 370 * driver is not allowed to change anything outside of the free-standing 371 * state objects passed-in or assembled in the overall &drm_atomic_state 372 * update tracking structure. 373 * 374 * Also beware that userspace can request its own custom modes, neither 375 * core nor helpers filter modes to the list of probe modes reported by 376 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 377 * that modes are filtered consistently put any CRTC constraints and 378 * limits checks into @mode_valid. 379 * 380 * RETURNS: 381 * 382 * 0 on success, -EINVAL if the state or the transition can't be 383 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 384 * attempt to obtain another state object ran into a &drm_modeset_lock 385 * deadlock. 386 */ 387 int (*atomic_check)(struct drm_crtc *crtc, 388 struct drm_crtc_state *state); 389 390 /** 391 * @atomic_begin: 392 * 393 * Drivers should prepare for an atomic update of multiple planes on 394 * a CRTC in this hook. Depending upon hardware this might be vblank 395 * evasion, blocking updates by setting bits or doing preparatory work 396 * for e.g. manual update display. 397 * 398 * This hook is called before any plane commit functions are called. 399 * 400 * Note that the power state of the display pipe when this function is 401 * called depends upon the exact helpers and calling sequence the driver 402 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 403 * the tradeoffs and variants of plane commit helpers. 404 * 405 * This callback is used by the atomic modeset helpers and by the 406 * transitional plane helpers, but it is optional. 407 */ 408 void (*atomic_begin)(struct drm_crtc *crtc, 409 struct drm_crtc_state *old_crtc_state); 410 /** 411 * @atomic_flush: 412 * 413 * Drivers should finalize an atomic update of multiple planes on 414 * a CRTC in this hook. Depending upon hardware this might include 415 * checking that vblank evasion was successful, unblocking updates by 416 * setting bits or setting the GO bit to flush out all updates. 417 * 418 * Simple hardware or hardware with special requirements can commit and 419 * flush out all updates for all planes from this hook and forgo all the 420 * other commit hooks for plane updates. 421 * 422 * This hook is called after any plane commit functions are called. 423 * 424 * Note that the power state of the display pipe when this function is 425 * called depends upon the exact helpers and calling sequence the driver 426 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 427 * the tradeoffs and variants of plane commit helpers. 428 * 429 * This callback is used by the atomic modeset helpers and by the 430 * transitional plane helpers, but it is optional. 431 */ 432 void (*atomic_flush)(struct drm_crtc *crtc, 433 struct drm_crtc_state *old_crtc_state); 434 435 /** 436 * @atomic_disable: 437 * 438 * This callback should be used to disable the CRTC. With the atomic 439 * drivers it is called after all encoders connected to this CRTC have 440 * been shut off already using their own 441 * &drm_encoder_helper_funcs.disable hook. If that sequence is too 442 * simple drivers can just add their own hooks and call it from this 443 * CRTC callback here by looping over all encoders connected to it using 444 * for_each_encoder_on_crtc(). 445 * 446 * This hook is used only by atomic helpers. Atomic drivers don't 447 * need to implement it if there's no need to disable anything at the 448 * CRTC level. 449 * 450 * Comparing to @disable, this one provides the additional input 451 * parameter @old_crtc_state which could be used to access the old 452 * state. Atomic drivers should consider to use this one instead 453 * of @disable. 454 */ 455 void (*atomic_disable)(struct drm_crtc *crtc, 456 struct drm_crtc_state *old_crtc_state); 457 }; 458 459 /** 460 * drm_crtc_helper_add - sets the helper vtable for a crtc 461 * @crtc: DRM CRTC 462 * @funcs: helper vtable to set for @crtc 463 */ 464 static inline void drm_crtc_helper_add(struct drm_crtc *crtc, 465 const struct drm_crtc_helper_funcs *funcs) 466 { 467 crtc->helper_private = funcs; 468 } 469 470 /** 471 * struct drm_encoder_helper_funcs - helper operations for encoders 472 * 473 * These hooks are used by the legacy CRTC helpers, the transitional plane 474 * helpers and the new atomic modesetting helpers. 475 */ 476 struct drm_encoder_helper_funcs { 477 /** 478 * @dpms: 479 * 480 * Callback to control power levels on the encoder. If the mode passed in 481 * is unsupported, the provider must use the next lowest power level. 482 * This is used by the legacy encoder helpers to implement DPMS 483 * functionality in drm_helper_connector_dpms(). 484 * 485 * This callback is also used to disable an encoder by calling it with 486 * DRM_MODE_DPMS_OFF if the @disable hook isn't used. 487 * 488 * This callback is used by the legacy CRTC helpers. Atomic helpers 489 * also support using this hook for enabling and disabling an encoder to 490 * facilitate transitions to atomic, but it is deprecated. Instead 491 * @enable and @disable should be used. 492 */ 493 void (*dpms)(struct drm_encoder *encoder, int mode); 494 495 /** 496 * @mode_valid: 497 * 498 * This callback is used to check if a specific mode is valid in this 499 * encoder. This should be implemented if the encoder has some sort 500 * of restriction in the modes it can display. For example, a given 501 * encoder may be responsible to set a clock value. If the clock can 502 * not produce all the values for the available modes then this callback 503 * can be used to restrict the number of modes to only the ones that 504 * can be displayed. 505 * 506 * This hook is used by the probe helpers to filter the mode list in 507 * drm_helper_probe_single_connector_modes(), and it is used by the 508 * atomic helpers to validate modes supplied by userspace in 509 * drm_atomic_helper_check_modeset(). 510 * 511 * This function is optional. 512 * 513 * NOTE: 514 * 515 * Since this function is both called from the check phase of an atomic 516 * commit, and the mode validation in the probe paths it is not allowed 517 * to look at anything else but the passed-in mode, and validate it 518 * against configuration-invariant hardward constraints. Any further 519 * limits which depend upon the configuration can only be checked in 520 * @mode_fixup or @atomic_check. 521 * 522 * RETURNS: 523 * 524 * drm_mode_status Enum 525 */ 526 enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc, 527 const struct drm_display_mode *mode); 528 529 /** 530 * @mode_fixup: 531 * 532 * This callback is used to validate and adjust a mode. The parameter 533 * mode is the display mode that should be fed to the next element in 534 * the display chain, either the final &drm_connector or a &drm_bridge. 535 * The parameter adjusted_mode is the input mode the encoder requires. It 536 * can be modified by this callback and does not need to match mode. See 537 * also &drm_crtc_state.adjusted_mode for more details. 538 * 539 * This function is used by both legacy CRTC helpers and atomic helpers. 540 * This hook is optional. 541 * 542 * NOTE: 543 * 544 * This function is called in the check phase of atomic modesets, which 545 * can be aborted for any reason (including on userspace's request to 546 * just check whether a configuration would be possible). Atomic drivers 547 * MUST NOT touch any persistent state (hardware or software) or data 548 * structures except the passed in adjusted_mode parameter. 549 * 550 * This is in contrast to the legacy CRTC helpers where this was 551 * allowed. 552 * 553 * Atomic drivers which need to inspect and adjust more state should 554 * instead use the @atomic_check callback. If @atomic_check is used, 555 * this hook isn't called since @atomic_check allows a strict superset 556 * of the functionality of @mode_fixup. 557 * 558 * Also beware that userspace can request its own custom modes, neither 559 * core nor helpers filter modes to the list of probe modes reported by 560 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 561 * that modes are filtered consistently put any encoder constraints and 562 * limits checks into @mode_valid. 563 * 564 * RETURNS: 565 * 566 * True if an acceptable configuration is possible, false if the modeset 567 * operation should be rejected. 568 */ 569 bool (*mode_fixup)(struct drm_encoder *encoder, 570 const struct drm_display_mode *mode, 571 struct drm_display_mode *adjusted_mode); 572 573 /** 574 * @prepare: 575 * 576 * This callback should prepare the encoder for a subsequent modeset, 577 * which in practice means the driver should disable the encoder if it 578 * is running. Most drivers ended up implementing this by calling their 579 * @dpms hook with DRM_MODE_DPMS_OFF. 580 * 581 * This callback is used by the legacy CRTC helpers. Atomic helpers 582 * also support using this hook for disabling an encoder to facilitate 583 * transitions to atomic, but it is deprecated. Instead @disable should 584 * be used. 585 */ 586 void (*prepare)(struct drm_encoder *encoder); 587 588 /** 589 * @commit: 590 * 591 * This callback should commit the new mode on the encoder after a modeset, 592 * which in practice means the driver should enable the encoder. Most 593 * drivers ended up implementing this by calling their @dpms hook with 594 * DRM_MODE_DPMS_ON. 595 * 596 * This callback is used by the legacy CRTC helpers. Atomic helpers 597 * also support using this hook for enabling an encoder to facilitate 598 * transitions to atomic, but it is deprecated. Instead @enable should 599 * be used. 600 */ 601 void (*commit)(struct drm_encoder *encoder); 602 603 /** 604 * @mode_set: 605 * 606 * This callback is used to update the display mode of an encoder. 607 * 608 * Note that the display pipe is completely off when this function is 609 * called. Drivers which need hardware to be running before they program 610 * the new display mode (because they implement runtime PM) should not 611 * use this hook, because the helper library calls it only once and not 612 * every time the display pipeline is suspend using either DPMS or the 613 * new "ACTIVE" property. Such drivers should instead move all their 614 * encoder setup into the @enable callback. 615 * 616 * This callback is used both by the legacy CRTC helpers and the atomic 617 * modeset helpers. It is optional in the atomic helpers. 618 * 619 * NOTE: 620 * 621 * If the driver uses the atomic modeset helpers and needs to inspect 622 * the connector state or connector display info during mode setting, 623 * @atomic_mode_set can be used instead. 624 */ 625 void (*mode_set)(struct drm_encoder *encoder, 626 struct drm_display_mode *mode, 627 struct drm_display_mode *adjusted_mode); 628 629 /** 630 * @atomic_mode_set: 631 * 632 * This callback is used to update the display mode of an encoder. 633 * 634 * Note that the display pipe is completely off when this function is 635 * called. Drivers which need hardware to be running before they program 636 * the new display mode (because they implement runtime PM) should not 637 * use this hook, because the helper library calls it only once and not 638 * every time the display pipeline is suspended using either DPMS or the 639 * new "ACTIVE" property. Such drivers should instead move all their 640 * encoder setup into the @enable callback. 641 * 642 * This callback is used by the atomic modeset helpers in place of the 643 * @mode_set callback, if set by the driver. It is optional and should 644 * be used instead of @mode_set if the driver needs to inspect the 645 * connector state or display info, since there is no direct way to 646 * go from the encoder to the current connector. 647 */ 648 void (*atomic_mode_set)(struct drm_encoder *encoder, 649 struct drm_crtc_state *crtc_state, 650 struct drm_connector_state *conn_state); 651 652 /** 653 * @get_crtc: 654 * 655 * This callback is used by the legacy CRTC helpers to work around 656 * deficiencies in its own book-keeping. 657 * 658 * Do not use, use atomic helpers instead, which get the book keeping 659 * right. 660 * 661 * FIXME: 662 * 663 * Currently only nouveau is using this, and as soon as nouveau is 664 * atomic we can ditch this hook. 665 */ 666 struct drm_crtc *(*get_crtc)(struct drm_encoder *encoder); 667 668 /** 669 * @detect: 670 * 671 * This callback can be used by drivers who want to do detection on the 672 * encoder object instead of in connector functions. 673 * 674 * It is not used by any helper and therefore has purely driver-specific 675 * semantics. New drivers shouldn't use this and instead just implement 676 * their own private callbacks. 677 * 678 * FIXME: 679 * 680 * This should just be converted into a pile of driver vfuncs. 681 * Currently radeon, amdgpu and nouveau are using it. 682 */ 683 enum drm_connector_status (*detect)(struct drm_encoder *encoder, 684 struct drm_connector *connector); 685 686 /** 687 * @disable: 688 * 689 * This callback should be used to disable the encoder. With the atomic 690 * drivers it is called before this encoder's CRTC has been shut off 691 * using their own &drm_crtc_helper_funcs.disable hook. If that 692 * sequence is too simple drivers can just add their own driver private 693 * encoder hooks and call them from CRTC's callback by looping over all 694 * encoders connected to it using for_each_encoder_on_crtc(). 695 * 696 * This hook is used both by legacy CRTC helpers and atomic helpers. 697 * Atomic drivers don't need to implement it if there's no need to 698 * disable anything at the encoder level. To ensure that runtime PM 699 * handling (using either DPMS or the new "ACTIVE" property) works 700 * @disable must be the inverse of @enable for atomic drivers. 701 * 702 * NOTE: 703 * 704 * With legacy CRTC helpers there's a big semantic difference between 705 * @disable and other hooks (like @prepare or @dpms) used to shut down a 706 * encoder: @disable is only called when also logically disabling the 707 * display pipeline and needs to release any resources acquired in 708 * @mode_set (like shared PLLs, or again release pinned framebuffers). 709 * 710 * Therefore @disable must be the inverse of @mode_set plus @commit for 711 * drivers still using legacy CRTC helpers, which is different from the 712 * rules under atomic. 713 */ 714 void (*disable)(struct drm_encoder *encoder); 715 716 /** 717 * @enable: 718 * 719 * This callback should be used to enable the encoder. With the atomic 720 * drivers it is called after this encoder's CRTC has been enabled using 721 * their own &drm_crtc_helper_funcs.enable hook. If that sequence is 722 * too simple drivers can just add their own driver private encoder 723 * hooks and call them from CRTC's callback by looping over all encoders 724 * connected to it using for_each_encoder_on_crtc(). 725 * 726 * This hook is used only by atomic helpers, for symmetry with @disable. 727 * Atomic drivers don't need to implement it if there's no need to 728 * enable anything at the encoder level. To ensure that runtime PM handling 729 * (using either DPMS or the new "ACTIVE" property) works 730 * @enable must be the inverse of @disable for atomic drivers. 731 */ 732 void (*enable)(struct drm_encoder *encoder); 733 734 /** 735 * @atomic_check: 736 * 737 * This callback is used to validate encoder state for atomic drivers. 738 * Since the encoder is the object connecting the CRTC and connector it 739 * gets passed both states, to be able to validate interactions and 740 * update the CRTC to match what the encoder needs for the requested 741 * connector. 742 * 743 * Since this provides a strict superset of the functionality of 744 * @mode_fixup (the requested and adjusted modes are both available 745 * through the passed in &struct drm_crtc_state) @mode_fixup is not 746 * called when @atomic_check is implemented. 747 * 748 * This function is used by the atomic helpers, but it is optional. 749 * 750 * NOTE: 751 * 752 * This function is called in the check phase of an atomic update. The 753 * driver is not allowed to change anything outside of the free-standing 754 * state objects passed-in or assembled in the overall &drm_atomic_state 755 * update tracking structure. 756 * 757 * Also beware that userspace can request its own custom modes, neither 758 * core nor helpers filter modes to the list of probe modes reported by 759 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 760 * that modes are filtered consistently put any encoder constraints and 761 * limits checks into @mode_valid. 762 * 763 * RETURNS: 764 * 765 * 0 on success, -EINVAL if the state or the transition can't be 766 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 767 * attempt to obtain another state object ran into a &drm_modeset_lock 768 * deadlock. 769 */ 770 int (*atomic_check)(struct drm_encoder *encoder, 771 struct drm_crtc_state *crtc_state, 772 struct drm_connector_state *conn_state); 773 }; 774 775 /** 776 * drm_encoder_helper_add - sets the helper vtable for an encoder 777 * @encoder: DRM encoder 778 * @funcs: helper vtable to set for @encoder 779 */ 780 static inline void drm_encoder_helper_add(struct drm_encoder *encoder, 781 const struct drm_encoder_helper_funcs *funcs) 782 { 783 encoder->helper_private = funcs; 784 } 785 786 /** 787 * struct drm_connector_helper_funcs - helper operations for connectors 788 * 789 * These functions are used by the atomic and legacy modeset helpers and by the 790 * probe helpers. 791 */ 792 struct drm_connector_helper_funcs { 793 /** 794 * @get_modes: 795 * 796 * This function should fill in all modes currently valid for the sink 797 * into the &drm_connector.probed_modes list. It should also update the 798 * EDID property by calling drm_mode_connector_update_edid_property(). 799 * 800 * The usual way to implement this is to cache the EDID retrieved in the 801 * probe callback somewhere in the driver-private connector structure. 802 * In this function drivers then parse the modes in the EDID and add 803 * them by calling drm_add_edid_modes(). But connectors that driver a 804 * fixed panel can also manually add specific modes using 805 * drm_mode_probed_add(). Drivers which manually add modes should also 806 * make sure that the &drm_connector.display_info, 807 * &drm_connector.width_mm and &drm_connector.height_mm fields are 808 * filled in. 809 * 810 * Virtual drivers that just want some standard VESA mode with a given 811 * resolution can call drm_add_modes_noedid(), and mark the preferred 812 * one using drm_set_preferred_mode(). 813 * 814 * Finally drivers that support audio probably want to update the ELD 815 * data, too, using drm_edid_to_eld(). 816 * 817 * This function is only called after the @detect hook has indicated 818 * that a sink is connected and when the EDID isn't overridden through 819 * sysfs or the kernel commandline. 820 * 821 * This callback is used by the probe helpers in e.g. 822 * drm_helper_probe_single_connector_modes(). 823 * 824 * To avoid races with concurrent connector state updates, the helper 825 * libraries always call this with the &drm_mode_config.connection_mutex 826 * held. Because of this it's safe to inspect &drm_connector->state. 827 * 828 * RETURNS: 829 * 830 * The number of modes added by calling drm_mode_probed_add(). 831 */ 832 int (*get_modes)(struct drm_connector *connector); 833 834 /** 835 * @detect_ctx: 836 * 837 * Check to see if anything is attached to the connector. The parameter 838 * force is set to false whilst polling, true when checking the 839 * connector due to a user request. force can be used by the driver to 840 * avoid expensive, destructive operations during automated probing. 841 * 842 * This callback is optional, if not implemented the connector will be 843 * considered as always being attached. 844 * 845 * This is the atomic version of &drm_connector_funcs.detect. 846 * 847 * To avoid races against concurrent connector state updates, the 848 * helper libraries always call this with ctx set to a valid context, 849 * and &drm_mode_config.connection_mutex will always be locked with 850 * the ctx parameter set to this ctx. This allows taking additional 851 * locks as required. 852 * 853 * RETURNS: 854 * 855 * &drm_connector_status indicating the connector's status, 856 * or the error code returned by drm_modeset_lock(), -EDEADLK. 857 */ 858 int (*detect_ctx)(struct drm_connector *connector, 859 struct drm_modeset_acquire_ctx *ctx, 860 bool force); 861 862 /** 863 * @mode_valid: 864 * 865 * Callback to validate a mode for a connector, irrespective of the 866 * specific display configuration. 867 * 868 * This callback is used by the probe helpers to filter the mode list 869 * (which is usually derived from the EDID data block from the sink). 870 * See e.g. drm_helper_probe_single_connector_modes(). 871 * 872 * This function is optional. 873 * 874 * NOTE: 875 * 876 * This only filters the mode list supplied to userspace in the 877 * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid, 878 * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid, 879 * which are also called by the atomic helpers from 880 * drm_atomic_helper_check_modeset(). This allows userspace to force and 881 * ignore sink constraint (like the pixel clock limits in the screen's 882 * EDID), which is useful for e.g. testing, or working around a broken 883 * EDID. Any source hardware constraint (which always need to be 884 * enforced) therefore should be checked in one of the above callbacks, 885 * and not this one here. 886 * 887 * To avoid races with concurrent connector state updates, the helper 888 * libraries always call this with the &drm_mode_config.connection_mutex 889 * held. Because of this it's safe to inspect &drm_connector->state. 890 * 891 * RETURNS: 892 * 893 * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum 894 * drm_mode_status. 895 */ 896 enum drm_mode_status (*mode_valid)(struct drm_connector *connector, 897 struct drm_display_mode *mode); 898 /** 899 * @best_encoder: 900 * 901 * This function should select the best encoder for the given connector. 902 * 903 * This function is used by both the atomic helpers (in the 904 * drm_atomic_helper_check_modeset() function) and in the legacy CRTC 905 * helpers. 906 * 907 * NOTE: 908 * 909 * In atomic drivers this function is called in the check phase of an 910 * atomic update. The driver is not allowed to change or inspect 911 * anything outside of arguments passed-in. Atomic drivers which need to 912 * inspect dynamic configuration state should instead use 913 * @atomic_best_encoder. 914 * 915 * You can leave this function to NULL if the connector is only 916 * attached to a single encoder and you are using the atomic helpers. 917 * In this case, the core will call drm_atomic_helper_best_encoder() 918 * for you. 919 * 920 * RETURNS: 921 * 922 * Encoder that should be used for the given connector and connector 923 * state, or NULL if no suitable encoder exists. Note that the helpers 924 * will ensure that encoders aren't used twice, drivers should not check 925 * for this. 926 */ 927 struct drm_encoder *(*best_encoder)(struct drm_connector *connector); 928 929 /** 930 * @atomic_best_encoder: 931 * 932 * This is the atomic version of @best_encoder for atomic drivers which 933 * need to select the best encoder depending upon the desired 934 * configuration and can't select it statically. 935 * 936 * This function is used by drm_atomic_helper_check_modeset(). 937 * If it is not implemented, the core will fallback to @best_encoder 938 * (or drm_atomic_helper_best_encoder() if @best_encoder is NULL). 939 * 940 * NOTE: 941 * 942 * This function is called in the check phase of an atomic update. The 943 * driver is not allowed to change anything outside of the free-standing 944 * state objects passed-in or assembled in the overall &drm_atomic_state 945 * update tracking structure. 946 * 947 * RETURNS: 948 * 949 * Encoder that should be used for the given connector and connector 950 * state, or NULL if no suitable encoder exists. Note that the helpers 951 * will ensure that encoders aren't used twice, drivers should not check 952 * for this. 953 */ 954 struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector, 955 struct drm_connector_state *connector_state); 956 957 /** 958 * @atomic_check: 959 * 960 * This hook is used to validate connector state. This function is 961 * called from &drm_atomic_helper_check_modeset, and is called when 962 * a connector property is set, or a modeset on the crtc is forced. 963 * 964 * Because &drm_atomic_helper_check_modeset may be called multiple times, 965 * this function should handle being called multiple times as well. 966 * 967 * This function is also allowed to inspect any other object's state and 968 * can add more state objects to the atomic commit if needed. Care must 969 * be taken though to ensure that state check and compute functions for 970 * these added states are all called, and derived state in other objects 971 * all updated. Again the recommendation is to just call check helpers 972 * until a maximal configuration is reached. 973 * 974 * NOTE: 975 * 976 * This function is called in the check phase of an atomic update. The 977 * driver is not allowed to change anything outside of the free-standing 978 * state objects passed-in or assembled in the overall &drm_atomic_state 979 * update tracking structure. 980 * 981 * RETURNS: 982 * 983 * 0 on success, -EINVAL if the state or the transition can't be 984 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 985 * attempt to obtain another state object ran into a &drm_modeset_lock 986 * deadlock. 987 */ 988 int (*atomic_check)(struct drm_connector *connector, 989 struct drm_connector_state *state); 990 }; 991 992 /** 993 * drm_connector_helper_add - sets the helper vtable for a connector 994 * @connector: DRM connector 995 * @funcs: helper vtable to set for @connector 996 */ 997 static inline void drm_connector_helper_add(struct drm_connector *connector, 998 const struct drm_connector_helper_funcs *funcs) 999 { 1000 connector->helper_private = funcs; 1001 } 1002 1003 /** 1004 * struct drm_plane_helper_funcs - helper operations for planes 1005 * 1006 * These functions are used by the atomic helpers and by the transitional plane 1007 * helpers. 1008 */ 1009 struct drm_plane_helper_funcs { 1010 /** 1011 * @prepare_fb: 1012 * 1013 * This hook is to prepare a framebuffer for scanout by e.g. pinning 1014 * it's backing storage or relocating it into a contiguous block of 1015 * VRAM. Other possible preparatory work includes flushing caches. 1016 * 1017 * This function must not block for outstanding rendering, since it is 1018 * called in the context of the atomic IOCTL even for async commits to 1019 * be able to return any errors to userspace. Instead the recommended 1020 * way is to fill out the fence member of the passed-in 1021 * &drm_plane_state. If the driver doesn't support native fences then 1022 * equivalent functionality should be implemented through private 1023 * members in the plane structure. 1024 * 1025 * The helpers will call @cleanup_fb with matching arguments for every 1026 * successful call to this hook. 1027 * 1028 * This callback is used by the atomic modeset helpers and by the 1029 * transitional plane helpers, but it is optional. 1030 * 1031 * RETURNS: 1032 * 1033 * 0 on success or one of the following negative error codes allowed by 1034 * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers 1035 * this callback is the only one which can fail an atomic commit, 1036 * everything else must complete successfully. 1037 */ 1038 int (*prepare_fb)(struct drm_plane *plane, 1039 struct drm_plane_state *new_state); 1040 /** 1041 * @cleanup_fb: 1042 * 1043 * This hook is called to clean up any resources allocated for the given 1044 * framebuffer and plane configuration in @prepare_fb. 1045 * 1046 * This callback is used by the atomic modeset helpers and by the 1047 * transitional plane helpers, but it is optional. 1048 */ 1049 void (*cleanup_fb)(struct drm_plane *plane, 1050 struct drm_plane_state *old_state); 1051 1052 /** 1053 * @atomic_check: 1054 * 1055 * Drivers should check plane specific constraints in this hook. 1056 * 1057 * When using drm_atomic_helper_check_planes() plane's @atomic_check 1058 * hooks are called before the ones for CRTCs, which allows drivers to 1059 * request shared resources that the CRTC controls here. For more 1060 * complicated dependencies the driver can call the provided check helpers 1061 * multiple times until the computed state has a final configuration and 1062 * everything has been checked. 1063 * 1064 * This function is also allowed to inspect any other object's state and 1065 * can add more state objects to the atomic commit if needed. Care must 1066 * be taken though to ensure that state check and compute functions for 1067 * these added states are all called, and derived state in other objects 1068 * all updated. Again the recommendation is to just call check helpers 1069 * until a maximal configuration is reached. 1070 * 1071 * This callback is used by the atomic modeset helpers and by the 1072 * transitional plane helpers, but it is optional. 1073 * 1074 * NOTE: 1075 * 1076 * This function is called in the check phase of an atomic update. The 1077 * driver is not allowed to change anything outside of the free-standing 1078 * state objects passed-in or assembled in the overall &drm_atomic_state 1079 * update tracking structure. 1080 * 1081 * RETURNS: 1082 * 1083 * 0 on success, -EINVAL if the state or the transition can't be 1084 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 1085 * attempt to obtain another state object ran into a &drm_modeset_lock 1086 * deadlock. 1087 */ 1088 int (*atomic_check)(struct drm_plane *plane, 1089 struct drm_plane_state *state); 1090 1091 /** 1092 * @atomic_update: 1093 * 1094 * Drivers should use this function to update the plane state. This 1095 * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and 1096 * drm_crtc_helper_funcs.atomic_flush callbacks. 1097 * 1098 * Note that the power state of the display pipe when this function is 1099 * called depends upon the exact helpers and calling sequence the driver 1100 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 1101 * the tradeoffs and variants of plane commit helpers. 1102 * 1103 * This callback is used by the atomic modeset helpers and by the 1104 * transitional plane helpers, but it is optional. 1105 */ 1106 void (*atomic_update)(struct drm_plane *plane, 1107 struct drm_plane_state *old_state); 1108 /** 1109 * @atomic_disable: 1110 * 1111 * Drivers should use this function to unconditionally disable a plane. 1112 * This hook is called in-between the 1113 * &drm_crtc_helper_funcs.atomic_begin and 1114 * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to 1115 * @atomic_update, which will be called for disabling planes, too, if 1116 * the @atomic_disable hook isn't implemented. 1117 * 1118 * This hook is also useful to disable planes in preparation of a modeset, 1119 * by calling drm_atomic_helper_disable_planes_on_crtc() from the 1120 * &drm_crtc_helper_funcs.disable hook. 1121 * 1122 * Note that the power state of the display pipe when this function is 1123 * called depends upon the exact helpers and calling sequence the driver 1124 * has picked. See drm_atomic_helper_commit_planes() for a discussion of 1125 * the tradeoffs and variants of plane commit helpers. 1126 * 1127 * This callback is used by the atomic modeset helpers and by the 1128 * transitional plane helpers, but it is optional. 1129 */ 1130 void (*atomic_disable)(struct drm_plane *plane, 1131 struct drm_plane_state *old_state); 1132 }; 1133 1134 /** 1135 * drm_plane_helper_add - sets the helper vtable for a plane 1136 * @plane: DRM plane 1137 * @funcs: helper vtable to set for @plane 1138 */ 1139 static inline void drm_plane_helper_add(struct drm_plane *plane, 1140 const struct drm_plane_helper_funcs *funcs) 1141 { 1142 plane->helper_private = funcs; 1143 } 1144 1145 /** 1146 * struct drm_mode_config_helper_funcs - global modeset helper operations 1147 * 1148 * These helper functions are used by the atomic helpers. 1149 */ 1150 struct drm_mode_config_helper_funcs { 1151 /** 1152 * @atomic_commit_tail: 1153 * 1154 * This hook is used by the default atomic_commit() hook implemented in 1155 * drm_atomic_helper_commit() together with the nonblocking commit 1156 * helpers (see drm_atomic_helper_setup_commit() for a starting point) 1157 * to implement blocking and nonblocking commits easily. It is not used 1158 * by the atomic helpers 1159 * 1160 * This function is called when the new atomic state has already been 1161 * swapped into the various state pointers. The passed in state 1162 * therefore contains copies of the old/previous state. This hook should 1163 * commit the new state into hardware. Note that the helpers have 1164 * already waited for preceeding atomic commits and fences, but drivers 1165 * can add more waiting calls at the start of their implementation, e.g. 1166 * to wait for driver-internal request for implicit syncing, before 1167 * starting to commit the update to the hardware. 1168 * 1169 * After the atomic update is committed to the hardware this hook needs 1170 * to call drm_atomic_helper_commit_hw_done(). Then wait for the upate 1171 * to be executed by the hardware, for example using 1172 * drm_atomic_helper_wait_for_vblanks(), and then clean up the old 1173 * framebuffers using drm_atomic_helper_cleanup_planes(). 1174 * 1175 * When disabling a CRTC this hook _must_ stall for the commit to 1176 * complete. Vblank waits don't work on disabled CRTC, hence the core 1177 * can't take care of this. And it also can't rely on the vblank event, 1178 * since that can be signalled already when the screen shows black, 1179 * which can happen much earlier than the last hardware access needed to 1180 * shut off the display pipeline completely. 1181 * 1182 * This hook is optional, the default implementation is 1183 * drm_atomic_helper_commit_tail(). 1184 */ 1185 void (*atomic_commit_tail)(struct drm_atomic_state *state); 1186 }; 1187 1188 #endif 1189