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 34 /** 35 * DOC: overview 36 * 37 * The DRM mode setting helper functions are common code for drivers to use if 38 * they wish. Drivers are not forced to use this code in their 39 * implementations but it would be useful if the code they do use at least 40 * provides a consistent interface and operation to userspace. Therefore it is 41 * highly recommended to use the provided helpers as much as possible. 42 * 43 * Because there is only one pointer per modeset object to hold a vfunc table 44 * for helper libraries they are by necessity shared among the different 45 * helpers. 46 * 47 * To make this clear all the helper vtables are pulled together in this location here. 48 */ 49 50 enum mode_set_atomic; 51 52 /** 53 * struct drm_crtc_helper_funcs - helper operations for CRTCs 54 * 55 * These hooks are used by the legacy CRTC helpers, the transitional plane 56 * helpers and the new atomic modesetting helpers. 57 */ 58 struct drm_crtc_helper_funcs { 59 /** 60 * @dpms: 61 * 62 * Callback to control power levels on the CRTC. If the mode passed in 63 * is unsupported, the provider must use the next lowest power level. 64 * This is used by the legacy CRTC helpers to implement DPMS 65 * functionality in drm_helper_connector_dpms(). 66 * 67 * This callback is also used to disable a CRTC by calling it with 68 * DRM_MODE_DPMS_OFF if the @disable hook isn't used. 69 * 70 * This callback is used by the legacy CRTC helpers. Atomic helpers 71 * also support using this hook for enabling and disabling a CRTC to 72 * facilitate transitions to atomic, but it is deprecated. Instead 73 * @enable and @disable should be used. 74 */ 75 void (*dpms)(struct drm_crtc *crtc, int mode); 76 77 /** 78 * @prepare: 79 * 80 * This callback should prepare the CRTC for a subsequent modeset, which 81 * in practice means the driver should disable the CRTC if it is 82 * running. Most drivers ended up implementing this by calling their 83 * @dpms hook with DRM_MODE_DPMS_OFF. 84 * 85 * This callback is used by the legacy CRTC helpers. Atomic helpers 86 * also support using this hook for disabling a CRTC to facilitate 87 * transitions to atomic, but it is deprecated. Instead @disable should 88 * be used. 89 */ 90 void (*prepare)(struct drm_crtc *crtc); 91 92 /** 93 * @commit: 94 * 95 * This callback should commit the new mode on the CRTC after a modeset, 96 * which in practice means the driver should enable the CRTC. Most 97 * drivers ended up implementing this by calling their @dpms hook with 98 * DRM_MODE_DPMS_ON. 99 * 100 * This callback is used by the legacy CRTC helpers. Atomic helpers 101 * also support using this hook for enabling a CRTC to facilitate 102 * transitions to atomic, but it is deprecated. Instead @enable should 103 * be used. 104 */ 105 void (*commit)(struct drm_crtc *crtc); 106 107 /** 108 * @mode_fixup: 109 * 110 * This callback is used to validate a mode. The parameter mode is the 111 * display mode that userspace requested, adjusted_mode is the mode the 112 * encoders need to be fed with. Note that this is the inverse semantics 113 * of the meaning for the &drm_encoder and &drm_bridge 114 * ->mode_fixup() functions. If the CRTC cannot support the requested 115 * conversion from mode to adjusted_mode it should reject the modeset. 116 * 117 * This function is used by both legacy CRTC helpers and atomic helpers. 118 * With atomic helpers it is optional. 119 * 120 * NOTE: 121 * 122 * This function is called in the check phase of atomic modesets, which 123 * can be aborted for any reason (including on userspace's request to 124 * just check whether a configuration would be possible). Atomic drivers 125 * MUST NOT touch any persistent state (hardware or software) or data 126 * structures except the passed in adjusted_mode parameter. 127 * 128 * This is in contrast to the legacy CRTC helpers where this was 129 * allowed. 130 * 131 * Atomic drivers which need to inspect and adjust more state should 132 * instead use the @atomic_check callback. 133 * 134 * Also beware that neither core nor helpers filter modes before 135 * passing them to the driver: While the list of modes that is 136 * advertised to userspace is filtered using the connector's 137 * ->mode_valid() callback, neither the core nor the helpers do any 138 * filtering on modes passed in from userspace when setting a mode. It 139 * is therefore possible for userspace to pass in a mode that was 140 * previously filtered out using ->mode_valid() or add a custom mode 141 * that wasn't probed from EDID or similar to begin with. Even though 142 * this is an advanced feature and rarely used nowadays, some users rely 143 * on being able to specify modes manually so drivers must be prepared 144 * to deal with it. Specifically this means that all drivers need not 145 * only validate modes in ->mode_valid() but also in ->mode_fixup() to 146 * make sure invalid modes passed in from userspace are rejected. 147 * 148 * RETURNS: 149 * 150 * True if an acceptable configuration is possible, false if the modeset 151 * operation should be rejected. 152 */ 153 bool (*mode_fixup)(struct drm_crtc *crtc, 154 const struct drm_display_mode *mode, 155 struct drm_display_mode *adjusted_mode); 156 157 /** 158 * @mode_set: 159 * 160 * This callback is used by the legacy CRTC helpers to set a new mode, 161 * position and framebuffer. Since it ties the primary plane to every 162 * mode change it is incompatible with universal plane support. And 163 * since it can't update other planes it's incompatible with atomic 164 * modeset support. 165 * 166 * This callback is only used by CRTC helpers and deprecated. 167 * 168 * RETURNS: 169 * 170 * 0 on success or a negative error code on failure. 171 */ 172 int (*mode_set)(struct drm_crtc *crtc, struct drm_display_mode *mode, 173 struct drm_display_mode *adjusted_mode, int x, int y, 174 struct drm_framebuffer *old_fb); 175 176 /** 177 * @mode_set_nofb: 178 * 179 * This callback is used to update the display mode of a CRTC without 180 * changing anything of the primary plane configuration. This fits the 181 * requirement of atomic and hence is used by the atomic helpers. It is 182 * also used by the transitional plane helpers to implement a 183 * @mode_set hook in drm_helper_crtc_mode_set(). 184 * 185 * Note that the display pipe is completely off when this function is 186 * called. Atomic drivers which need hardware to be running before they 187 * program the new display mode (e.g. because they implement runtime PM) 188 * should not use this hook. This is because the helper library calls 189 * this hook only once per mode change and not every time the display 190 * pipeline is suspended using either DPMS or the new "ACTIVE" property. 191 * Which means register values set in this callback might get reset when 192 * the CRTC is suspended, but not restored. Such drivers should instead 193 * move all their CRTC setup into the @enable callback. 194 * 195 * This callback is optional. 196 */ 197 void (*mode_set_nofb)(struct drm_crtc *crtc); 198 199 /** 200 * @mode_set_base: 201 * 202 * This callback is used by the legacy CRTC helpers to set a new 203 * framebuffer and scanout position. It is optional and used as an 204 * optimized fast-path instead of a full mode set operation with all the 205 * resulting flickering. If it is not present 206 * drm_crtc_helper_set_config() will fall back to a full modeset, using 207 * the ->mode_set() callback. Since it can't update other planes it's 208 * incompatible with atomic modeset support. 209 * 210 * This callback is only used by the CRTC helpers and deprecated. 211 * 212 * RETURNS: 213 * 214 * 0 on success or a negative error code on failure. 215 */ 216 int (*mode_set_base)(struct drm_crtc *crtc, int x, int y, 217 struct drm_framebuffer *old_fb); 218 219 /** 220 * @mode_set_base_atomic: 221 * 222 * This callback is used by the fbdev helpers to set a new framebuffer 223 * and scanout without sleeping, i.e. from an atomic calling context. It 224 * is only used to implement kgdb support. 225 * 226 * This callback is optional and only needed for kgdb support in the fbdev 227 * helpers. 228 * 229 * RETURNS: 230 * 231 * 0 on success or a negative error code on failure. 232 */ 233 int (*mode_set_base_atomic)(struct drm_crtc *crtc, 234 struct drm_framebuffer *fb, int x, int y, 235 enum mode_set_atomic); 236 237 /** 238 * @load_lut: 239 * 240 * Load a LUT prepared with the @gamma_set functions from 241 * &drm_fb_helper_funcs. 242 * 243 * This callback is optional and is only used by the fbdev emulation 244 * helpers. 245 * 246 * FIXME: 247 * 248 * This callback is functionally redundant with the core gamma table 249 * support and simply exists because the fbdev hasn't yet been 250 * refactored to use the core gamma table interfaces. 251 */ 252 void (*load_lut)(struct drm_crtc *crtc); 253 254 /** 255 * @disable: 256 * 257 * This callback should be used to disable the CRTC. With the atomic 258 * drivers it is called after all encoders connected to this CRTC have 259 * been shut off already using their own ->disable hook. If that 260 * sequence is too simple drivers can just add their own hooks and call 261 * it from this CRTC callback here by looping over all encoders 262 * connected to it using for_each_encoder_on_crtc(). 263 * 264 * This hook is used both by legacy CRTC helpers and atomic helpers. 265 * Atomic drivers don't need to implement it if there's no need to 266 * disable anything at the CRTC level. To ensure that runtime PM 267 * handling (using either DPMS or the new "ACTIVE" property) works 268 * @disable must be the inverse of @enable for atomic drivers. 269 * 270 * NOTE: 271 * 272 * With legacy CRTC helpers there's a big semantic difference between 273 * @disable and other hooks (like @prepare or @dpms) used to shut down a 274 * CRTC: @disable is only called when also logically disabling the 275 * display pipeline and needs to release any resources acquired in 276 * @mode_set (like shared PLLs, or again release pinned framebuffers). 277 * 278 * Therefore @disable must be the inverse of @mode_set plus @commit for 279 * drivers still using legacy CRTC helpers, which is different from the 280 * rules under atomic. 281 */ 282 void (*disable)(struct drm_crtc *crtc); 283 284 /** 285 * @enable: 286 * 287 * This callback should be used to enable the CRTC. With the atomic 288 * drivers it is called before all encoders connected to this CRTC are 289 * enabled through the encoder's own ->enable hook. If that sequence is 290 * too simple drivers can just add their own hooks and call it from this 291 * CRTC callback here by looping over all encoders connected to it using 292 * for_each_encoder_on_crtc(). 293 * 294 * This hook is used only by atomic helpers, for symmetry with @disable. 295 * Atomic drivers don't need to implement it if there's no need to 296 * enable anything at the CRTC level. To ensure that runtime PM handling 297 * (using either DPMS or the new "ACTIVE" property) works 298 * @enable must be the inverse of @disable for atomic drivers. 299 */ 300 void (*enable)(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() CRTCs' ->atomic_check() 317 * hooks are called after the ones for planes, which allows drivers to 318 * assign shared resources requested by planes in the CRTC callback 319 * here. For more complicated dependencies the driver can call the provided 320 * check helpers multiple times until the computed state has a final 321 * 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&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 * RETURNS: 341 * 342 * 0 on success, -EINVAL if the state or the transition can't be 343 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 344 * attempt to obtain another state object ran into a &drm_modeset_lock 345 * deadlock. 346 */ 347 int (*atomic_check)(struct drm_crtc *crtc, 348 struct drm_crtc_state *state); 349 350 /** 351 * @atomic_begin: 352 * 353 * Drivers should prepare for an atomic update of multiple planes on 354 * a CRTC in this hook. Depending upon hardware this might be vblank 355 * evasion, blocking updates by setting bits or doing preparatory work 356 * for e.g. manual update display. 357 * 358 * This hook is called before any plane commit functions are called. 359 * 360 * Note that the power state of the display pipe when this function is 361 * called depends upon the exact helpers and calling sequence the driver 362 * has picked. See drm_atomic_commit_planes() for a discussion of the 363 * tradeoffs and variants of plane commit helpers. 364 * 365 * This callback is used by the atomic modeset helpers and by the 366 * transitional plane helpers, but it is optional. 367 */ 368 void (*atomic_begin)(struct drm_crtc *crtc, 369 struct drm_crtc_state *old_crtc_state); 370 /** 371 * @atomic_flush: 372 * 373 * Drivers should finalize an atomic update of multiple planes on 374 * a CRTC in this hook. Depending upon hardware this might include 375 * checking that vblank evasion was successful, unblocking updates by 376 * setting bits or setting the GO bit to flush out all updates. 377 * 378 * Simple hardware or hardware with special requirements can commit and 379 * flush out all updates for all planes from this hook and forgo all the 380 * other commit hooks for plane updates. 381 * 382 * This hook is called after any plane commit functions are called. 383 * 384 * Note that the power state of the display pipe when this function is 385 * called depends upon the exact helpers and calling sequence the driver 386 * has picked. See drm_atomic_commit_planes() for a discussion of the 387 * tradeoffs and variants of plane commit helpers. 388 * 389 * This callback is used by the atomic modeset helpers and by the 390 * transitional plane helpers, but it is optional. 391 */ 392 void (*atomic_flush)(struct drm_crtc *crtc, 393 struct drm_crtc_state *old_crtc_state); 394 }; 395 396 /** 397 * drm_crtc_helper_add - sets the helper vtable for a crtc 398 * @crtc: DRM CRTC 399 * @funcs: helper vtable to set for @crtc 400 */ 401 static inline void drm_crtc_helper_add(struct drm_crtc *crtc, 402 const struct drm_crtc_helper_funcs *funcs) 403 { 404 crtc->helper_private = funcs; 405 } 406 407 /** 408 * struct drm_encoder_helper_funcs - helper operations for encoders 409 * 410 * These hooks are used by the legacy CRTC helpers, the transitional plane 411 * helpers and the new atomic modesetting helpers. 412 */ 413 struct drm_encoder_helper_funcs { 414 /** 415 * @dpms: 416 * 417 * Callback to control power levels on the encoder. If the mode passed in 418 * is unsupported, the provider must use the next lowest power level. 419 * This is used by the legacy encoder helpers to implement DPMS 420 * functionality in drm_helper_connector_dpms(). 421 * 422 * This callback is also used to disable an encoder by calling it with 423 * DRM_MODE_DPMS_OFF if the @disable hook isn't used. 424 * 425 * This callback is used by the legacy CRTC helpers. Atomic helpers 426 * also support using this hook for enabling and disabling an encoder to 427 * facilitate transitions to atomic, but it is deprecated. Instead 428 * @enable and @disable should be used. 429 */ 430 void (*dpms)(struct drm_encoder *encoder, int mode); 431 432 /** 433 * @mode_fixup: 434 * 435 * This callback is used to validate and adjust a mode. The parameter 436 * mode is the display mode that should be fed to the next element in 437 * the display chain, either the final &drm_connector or a &drm_bridge. 438 * The parameter adjusted_mode is the input mode the encoder requires. It 439 * can be modified by this callback and does not need to match mode. 440 * 441 * This function is used by both legacy CRTC helpers and atomic helpers. 442 * This hook is optional. 443 * 444 * NOTE: 445 * 446 * This function is called in the check phase of atomic modesets, which 447 * can be aborted for any reason (including on userspace's request to 448 * just check whether a configuration would be possible). Atomic drivers 449 * MUST NOT touch any persistent state (hardware or software) or data 450 * structures except the passed in adjusted_mode parameter. 451 * 452 * This is in contrast to the legacy CRTC helpers where this was 453 * allowed. 454 * 455 * Atomic drivers which need to inspect and adjust more state should 456 * instead use the @atomic_check callback. 457 * 458 * Also beware that neither core nor helpers filter modes before 459 * passing them to the driver: While the list of modes that is 460 * advertised to userspace is filtered using the connector's 461 * ->mode_valid() callback, neither the core nor the helpers do any 462 * filtering on modes passed in from userspace when setting a mode. It 463 * is therefore possible for userspace to pass in a mode that was 464 * previously filtered out using ->mode_valid() or add a custom mode 465 * that wasn't probed from EDID or similar to begin with. Even though 466 * this is an advanced feature and rarely used nowadays, some users rely 467 * on being able to specify modes manually so drivers must be prepared 468 * to deal with it. Specifically this means that all drivers need not 469 * only validate modes in ->mode_valid() but also in ->mode_fixup() to 470 * make sure invalid modes passed in from userspace are rejected. 471 * 472 * RETURNS: 473 * 474 * True if an acceptable configuration is possible, false if the modeset 475 * operation should be rejected. 476 */ 477 bool (*mode_fixup)(struct drm_encoder *encoder, 478 const struct drm_display_mode *mode, 479 struct drm_display_mode *adjusted_mode); 480 481 /** 482 * @prepare: 483 * 484 * This callback should prepare the encoder for a subsequent modeset, 485 * which in practice means the driver should disable the encoder if it 486 * is running. Most drivers ended up implementing this by calling their 487 * @dpms hook with DRM_MODE_DPMS_OFF. 488 * 489 * This callback is used by the legacy CRTC helpers. Atomic helpers 490 * also support using this hook for disabling an encoder to facilitate 491 * transitions to atomic, but it is deprecated. Instead @disable should 492 * be used. 493 */ 494 void (*prepare)(struct drm_encoder *encoder); 495 496 /** 497 * @commit: 498 * 499 * This callback should commit the new mode on the encoder after a modeset, 500 * which in practice means the driver should enable the encoder. Most 501 * drivers ended up implementing this by calling their @dpms hook with 502 * DRM_MODE_DPMS_ON. 503 * 504 * This callback is used by the legacy CRTC helpers. Atomic helpers 505 * also support using this hook for enabling an encoder to facilitate 506 * transitions to atomic, but it is deprecated. Instead @enable should 507 * be used. 508 */ 509 void (*commit)(struct drm_encoder *encoder); 510 511 /** 512 * @mode_set: 513 * 514 * This callback is used to update the display mode of an encoder. 515 * 516 * Note that the display pipe is completely off when this function is 517 * called. Drivers which need hardware to be running before they program 518 * the new display mode (because they implement runtime PM) should not 519 * use this hook, because the helper library calls it only once and not 520 * every time the display pipeline is suspend using either DPMS or the 521 * new "ACTIVE" property. Such drivers should instead move all their 522 * encoder setup into the ->enable() callback. 523 * 524 * This callback is used both by the legacy CRTC helpers and the atomic 525 * modeset helpers. It is optional in the atomic helpers. 526 */ 527 void (*mode_set)(struct drm_encoder *encoder, 528 struct drm_display_mode *mode, 529 struct drm_display_mode *adjusted_mode); 530 531 /** 532 * @get_crtc: 533 * 534 * This callback is used by the legacy CRTC helpers to work around 535 * deficiencies in its own book-keeping. 536 * 537 * Do not use, use atomic helpers instead, which get the book keeping 538 * right. 539 * 540 * FIXME: 541 * 542 * Currently only nouveau is using this, and as soon as nouveau is 543 * atomic we can ditch this hook. 544 */ 545 struct drm_crtc *(*get_crtc)(struct drm_encoder *encoder); 546 547 /** 548 * @detect: 549 * 550 * This callback can be used by drivers who want to do detection on the 551 * encoder object instead of in connector functions. 552 * 553 * It is not used by any helper and therefore has purely driver-specific 554 * semantics. New drivers shouldn't use this and instead just implement 555 * their own private callbacks. 556 * 557 * FIXME: 558 * 559 * This should just be converted into a pile of driver vfuncs. 560 * Currently radeon, amdgpu and nouveau are using it. 561 */ 562 enum drm_connector_status (*detect)(struct drm_encoder *encoder, 563 struct drm_connector *connector); 564 565 /** 566 * @disable: 567 * 568 * This callback should be used to disable the encoder. With the atomic 569 * drivers it is called before this encoder's CRTC has been shut off 570 * using the CRTC's own ->disable hook. If that sequence is too simple 571 * drivers can just add their own driver private encoder hooks and call 572 * them from CRTC's callback by looping over all encoders connected to 573 * it using for_each_encoder_on_crtc(). 574 * 575 * This hook is used both by legacy CRTC helpers and atomic helpers. 576 * Atomic drivers don't need to implement it if there's no need to 577 * disable anything at the encoder level. To ensure that runtime PM 578 * handling (using either DPMS or the new "ACTIVE" property) works 579 * @disable must be the inverse of @enable for atomic drivers. 580 * 581 * NOTE: 582 * 583 * With legacy CRTC helpers there's a big semantic difference between 584 * @disable and other hooks (like @prepare or @dpms) used to shut down a 585 * encoder: @disable is only called when also logically disabling the 586 * display pipeline and needs to release any resources acquired in 587 * @mode_set (like shared PLLs, or again release pinned framebuffers). 588 * 589 * Therefore @disable must be the inverse of @mode_set plus @commit for 590 * drivers still using legacy CRTC helpers, which is different from the 591 * rules under atomic. 592 */ 593 void (*disable)(struct drm_encoder *encoder); 594 595 /** 596 * @enable: 597 * 598 * This callback should be used to enable the encoder. With the atomic 599 * drivers it is called after this encoder's CRTC has been enabled using 600 * the CRTC's own ->enable hook. If that sequence is too simple drivers 601 * can just add their own driver private encoder hooks and call them 602 * from CRTC's callback by looping over all encoders connected to it 603 * using for_each_encoder_on_crtc(). 604 * 605 * This hook is used only by atomic helpers, for symmetry with @disable. 606 * Atomic drivers don't need to implement it if there's no need to 607 * enable anything at the encoder level. To ensure that runtime PM handling 608 * (using either DPMS or the new "ACTIVE" property) works 609 * @enable must be the inverse of @disable for atomic drivers. 610 */ 611 void (*enable)(struct drm_encoder *encoder); 612 613 /** 614 * @atomic_check: 615 * 616 * This callback is used to validate encoder state for atomic drivers. 617 * Since the encoder is the object connecting the CRTC and connector it 618 * gets passed both states, to be able to validate interactions and 619 * update the CRTC to match what the encoder needs for the requested 620 * connector. 621 * 622 * This function is used by the atomic helpers, but it is optional. 623 * 624 * NOTE: 625 * 626 * This function is called in the check phase of an atomic update. The 627 * driver is not allowed to change anything outside of the free-standing 628 * state objects passed-in or assembled in the overall &drm_atomic_state 629 * update tracking structure. 630 * 631 * RETURNS: 632 * 633 * 0 on success, -EINVAL if the state or the transition can't be 634 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 635 * attempt to obtain another state object ran into a &drm_modeset_lock 636 * deadlock. 637 */ 638 int (*atomic_check)(struct drm_encoder *encoder, 639 struct drm_crtc_state *crtc_state, 640 struct drm_connector_state *conn_state); 641 }; 642 643 /** 644 * drm_encoder_helper_add - sets the helper vtable for an encoder 645 * @encoder: DRM encoder 646 * @funcs: helper vtable to set for @encoder 647 */ 648 static inline void drm_encoder_helper_add(struct drm_encoder *encoder, 649 const struct drm_encoder_helper_funcs *funcs) 650 { 651 encoder->helper_private = funcs; 652 } 653 654 /** 655 * struct drm_connector_helper_funcs - helper operations for connectors 656 * 657 * These functions are used by the atomic and legacy modeset helpers and by the 658 * probe helpers. 659 */ 660 struct drm_connector_helper_funcs { 661 /** 662 * @get_modes: 663 * 664 * This function should fill in all modes currently valid for the sink 665 * into the connector->probed_modes list. It should also update the 666 * EDID property by calling drm_mode_connector_update_edid_property(). 667 * 668 * The usual way to implement this is to cache the EDID retrieved in the 669 * probe callback somewhere in the driver-private connector structure. 670 * In this function drivers then parse the modes in the EDID and add 671 * them by calling drm_add_edid_modes(). But connectors that driver a 672 * fixed panel can also manually add specific modes using 673 * drm_mode_probed_add(). Drivers which manually add modes should also 674 * make sure that the @display_info, @width_mm and @height_mm fields of the 675 * struct #drm_connector are filled in. 676 * 677 * Virtual drivers that just want some standard VESA mode with a given 678 * resolution can call drm_add_modes_noedid(), and mark the preferred 679 * one using drm_set_preferred_mode(). 680 * 681 * Finally drivers that support audio probably want to update the ELD 682 * data, too, using drm_edid_to_eld(). 683 * 684 * This function is only called after the ->detect() hook has indicated 685 * that a sink is connected and when the EDID isn't overridden through 686 * sysfs or the kernel commandline. 687 * 688 * This callback is used by the probe helpers in e.g. 689 * drm_helper_probe_single_connector_modes(). 690 * 691 * RETURNS: 692 * 693 * The number of modes added by calling drm_mode_probed_add(). 694 */ 695 int (*get_modes)(struct drm_connector *connector); 696 697 /** 698 * @mode_valid: 699 * 700 * Callback to validate a mode for a connector, irrespective of the 701 * specific display configuration. 702 * 703 * This callback is used by the probe helpers to filter the mode list 704 * (which is usually derived from the EDID data block from the sink). 705 * See e.g. drm_helper_probe_single_connector_modes(). 706 * 707 * NOTE: 708 * 709 * This only filters the mode list supplied to userspace in the 710 * GETCONNECOTR IOCTL. Userspace is free to create modes of its own and 711 * ask the kernel to use them. It this case the atomic helpers or legacy 712 * CRTC helpers will not call this function. Drivers therefore must 713 * still fully validate any mode passed in in a modeset request. 714 * 715 * RETURNS: 716 * 717 * Either MODE_OK or one of the failure reasons in enum 718 * &drm_mode_status. 719 */ 720 enum drm_mode_status (*mode_valid)(struct drm_connector *connector, 721 struct drm_display_mode *mode); 722 /** 723 * @best_encoder: 724 * 725 * This function should select the best encoder for the given connector. 726 * 727 * This function is used by both the atomic helpers (in the 728 * drm_atomic_helper_check_modeset() function) and in the legacy CRTC 729 * helpers. 730 * 731 * NOTE: 732 * 733 * In atomic drivers this function is called in the check phase of an 734 * atomic update. The driver is not allowed to change or inspect 735 * anything outside of arguments passed-in. Atomic drivers which need to 736 * inspect dynamic configuration state should instead use 737 * @atomic_best_encoder. 738 * 739 * RETURNS: 740 * 741 * Encoder that should be used for the given connector and connector 742 * state, or NULL if no suitable encoder exists. Note that the helpers 743 * will ensure that encoders aren't used twice, drivers should not check 744 * for this. 745 */ 746 struct drm_encoder *(*best_encoder)(struct drm_connector *connector); 747 748 /** 749 * @atomic_best_encoder: 750 * 751 * This is the atomic version of @best_encoder for atomic drivers which 752 * need to select the best encoder depending upon the desired 753 * configuration and can't select it statically. 754 * 755 * This function is used by drm_atomic_helper_check_modeset() and either 756 * this or @best_encoder is required. 757 * 758 * NOTE: 759 * 760 * This function is called in the check phase of an atomic update. The 761 * driver is not allowed to change anything outside of the free-standing 762 * state objects passed-in or assembled in the overall &drm_atomic_state 763 * update tracking structure. 764 * 765 * RETURNS: 766 * 767 * Encoder that should be used for the given connector and connector 768 * state, or NULL if no suitable encoder exists. Note that the helpers 769 * will ensure that encoders aren't used twice, drivers should not check 770 * for this. 771 */ 772 struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector, 773 struct drm_connector_state *connector_state); 774 }; 775 776 /** 777 * drm_connector_helper_add - sets the helper vtable for a connector 778 * @connector: DRM connector 779 * @funcs: helper vtable to set for @connector 780 */ 781 static inline void drm_connector_helper_add(struct drm_connector *connector, 782 const struct drm_connector_helper_funcs *funcs) 783 { 784 connector->helper_private = funcs; 785 } 786 787 /** 788 * struct drm_plane_helper_funcs - helper operations for planes 789 * 790 * These functions are used by the atomic helpers and by the transitional plane 791 * helpers. 792 */ 793 struct drm_plane_helper_funcs { 794 /** 795 * @prepare_fb: 796 * 797 * This hook is to prepare a framebuffer for scanout by e.g. pinning 798 * it's backing storage or relocating it into a contiguous block of 799 * VRAM. Other possible preparatory work includes flushing caches. 800 * 801 * This function must not block for outstanding rendering, since it is 802 * called in the context of the atomic IOCTL even for async commits to 803 * be able to return any errors to userspace. Instead the recommended 804 * way is to fill out the fence member of the passed-in 805 * &drm_plane_state. If the driver doesn't support native fences then 806 * equivalent functionality should be implemented through private 807 * members in the plane structure. 808 * 809 * The helpers will call @cleanup_fb with matching arguments for every 810 * successful call to this hook. 811 * 812 * This callback is used by the atomic modeset helpers and by the 813 * transitional plane helpers, but it is optional. 814 * 815 * RETURNS: 816 * 817 * 0 on success or one of the following negative error codes allowed by 818 * the atomic_commit hook in &drm_mode_config_funcs. When using helpers 819 * this callback is the only one which can fail an atomic commit, 820 * everything else must complete successfully. 821 */ 822 int (*prepare_fb)(struct drm_plane *plane, 823 struct drm_plane_state *new_state); 824 /** 825 * @cleanup_fb: 826 * 827 * This hook is called to clean up any resources allocated for the given 828 * framebuffer and plane configuration in @prepare_fb. 829 * 830 * This callback is used by the atomic modeset helpers and by the 831 * transitional plane helpers, but it is optional. 832 */ 833 void (*cleanup_fb)(struct drm_plane *plane, 834 struct drm_plane_state *old_state); 835 836 /** 837 * @atomic_check: 838 * 839 * Drivers should check plane specific constraints in this hook. 840 * 841 * When using drm_atomic_helper_check_planes() plane's ->atomic_check() 842 * hooks are called before the ones for CRTCs, which allows drivers to 843 * request shared resources that the CRTC controls here. For more 844 * complicated dependencies the driver can call the provided check helpers 845 * multiple times until the computed state has a final configuration and 846 * everything has been checked. 847 * 848 * This function is also allowed to inspect any other object's state and 849 * can add more state objects to the atomic commit if needed. Care must 850 * be taken though to ensure that state check&compute functions for 851 * these added states are all called, and derived state in other objects 852 * all updated. Again the recommendation is to just call check helpers 853 * until a maximal configuration is reached. 854 * 855 * This callback is used by the atomic modeset helpers and by the 856 * transitional plane helpers, but it is optional. 857 * 858 * NOTE: 859 * 860 * This function is called in the check phase of an atomic update. The 861 * driver is not allowed to change anything outside of the free-standing 862 * state objects passed-in or assembled in the overall &drm_atomic_state 863 * update tracking structure. 864 * 865 * RETURNS: 866 * 867 * 0 on success, -EINVAL if the state or the transition can't be 868 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an 869 * attempt to obtain another state object ran into a &drm_modeset_lock 870 * deadlock. 871 */ 872 int (*atomic_check)(struct drm_plane *plane, 873 struct drm_plane_state *state); 874 875 /** 876 * @atomic_update: 877 * 878 * Drivers should use this function to update the plane state. This 879 * hook is called in-between the ->atomic_begin() and 880 * ->atomic_flush() of &drm_crtc_helper_funcs. 881 * 882 * Note that the power state of the display pipe when this function is 883 * called depends upon the exact helpers and calling sequence the driver 884 * has picked. See drm_atomic_commit_planes() for a discussion of the 885 * tradeoffs and variants of plane commit helpers. 886 * 887 * This callback is used by the atomic modeset helpers and by the 888 * transitional plane helpers, but it is optional. 889 */ 890 void (*atomic_update)(struct drm_plane *plane, 891 struct drm_plane_state *old_state); 892 /** 893 * @atomic_disable: 894 * 895 * Drivers should use this function to unconditionally disable a plane. 896 * This hook is called in-between the ->atomic_begin() and 897 * ->atomic_flush() of &drm_crtc_helper_funcs. It is an alternative to 898 * @atomic_update, which will be called for disabling planes, too, if 899 * the @atomic_disable hook isn't implemented. 900 * 901 * This hook is also useful to disable planes in preparation of a modeset, 902 * by calling drm_atomic_helper_disable_planes_on_crtc() from the 903 * ->disable() hook in &drm_crtc_helper_funcs. 904 * 905 * Note that the power state of the display pipe when this function is 906 * called depends upon the exact helpers and calling sequence the driver 907 * has picked. See drm_atomic_commit_planes() for a discussion of the 908 * tradeoffs and variants of plane commit helpers. 909 * 910 * This callback is used by the atomic modeset helpers and by the 911 * transitional plane helpers, but it is optional. 912 */ 913 void (*atomic_disable)(struct drm_plane *plane, 914 struct drm_plane_state *old_state); 915 }; 916 917 /** 918 * drm_plane_helper_add - sets the helper vtable for a plane 919 * @plane: DRM plane 920 * @funcs: helper vtable to set for @plane 921 */ 922 static inline void drm_plane_helper_add(struct drm_plane *plane, 923 const struct drm_plane_helper_funcs *funcs) 924 { 925 plane->helper_private = funcs; 926 } 927 928 #endif 929