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