1 /* 2 * Copyright (C) 2018 Intel Corp. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice shall be included in 12 * all copies or substantial portions of the Software. 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 20 * OTHER DEALINGS IN THE SOFTWARE. 21 * 22 * Authors: 23 * Rob Clark <robdclark@gmail.com> 24 * Daniel Vetter <daniel.vetter@ffwll.ch> 25 */ 26 27 #include <drm/drm_atomic.h> 28 #include <drm/drm_atomic_state_helper.h> 29 #include <drm/drm_blend.h> 30 #include <drm/drm_bridge.h> 31 #include <drm/drm_connector.h> 32 #include <drm/drm_crtc.h> 33 #include <drm/drm_device.h> 34 #include <drm/drm_framebuffer.h> 35 #include <drm/drm_plane.h> 36 #include <drm/drm_print.h> 37 #include <drm/drm_vblank.h> 38 #include <drm/drm_writeback.h> 39 40 #include <linux/slab.h> 41 #include <linux/dma-fence.h> 42 43 /** 44 * DOC: atomic state reset and initialization 45 * 46 * Both the drm core and the atomic helpers assume that there is always the full 47 * and correct atomic software state for all connectors, CRTCs and planes 48 * available. Which is a bit a problem on driver load and also after system 49 * suspend. One way to solve this is to have a hardware state read-out 50 * infrastructure which reconstructs the full software state (e.g. the i915 51 * driver). 52 * 53 * The simpler solution is to just reset the software state to everything off, 54 * which is easiest to do by calling drm_mode_config_reset(). To facilitate this 55 * the atomic helpers provide default reset implementations for all hooks. 56 * 57 * On the upside the precise state tracking of atomic simplifies system suspend 58 * and resume a lot. For drivers using drm_mode_config_reset() a complete recipe 59 * is implemented in drm_atomic_helper_suspend() and drm_atomic_helper_resume(). 60 * For other drivers the building blocks are split out, see the documentation 61 * for these functions. 62 */ 63 64 /** 65 * __drm_atomic_helper_crtc_state_reset - reset the CRTC state 66 * @crtc_state: atomic CRTC state, must not be NULL 67 * @crtc: CRTC object, must not be NULL 68 * 69 * Initializes the newly allocated @crtc_state with default 70 * values. This is useful for drivers that subclass the CRTC state. 71 */ 72 void 73 __drm_atomic_helper_crtc_state_reset(struct drm_crtc_state *crtc_state, 74 struct drm_crtc *crtc) 75 { 76 crtc_state->crtc = crtc; 77 } 78 EXPORT_SYMBOL(__drm_atomic_helper_crtc_state_reset); 79 80 /** 81 * __drm_atomic_helper_crtc_reset - reset state on CRTC 82 * @crtc: drm CRTC 83 * @crtc_state: CRTC state to assign 84 * 85 * Initializes the newly allocated @crtc_state and assigns it to 86 * the &drm_crtc->state pointer of @crtc, usually required when 87 * initializing the drivers or when called from the &drm_crtc_funcs.reset 88 * hook. 89 * 90 * This is useful for drivers that subclass the CRTC state. 91 */ 92 void 93 __drm_atomic_helper_crtc_reset(struct drm_crtc *crtc, 94 struct drm_crtc_state *crtc_state) 95 { 96 if (crtc_state) 97 __drm_atomic_helper_crtc_state_reset(crtc_state, crtc); 98 99 if (drm_dev_has_vblank(crtc->dev)) 100 drm_crtc_vblank_reset(crtc); 101 102 crtc->state = crtc_state; 103 } 104 EXPORT_SYMBOL(__drm_atomic_helper_crtc_reset); 105 106 /** 107 * drm_atomic_helper_crtc_reset - default &drm_crtc_funcs.reset hook for CRTCs 108 * @crtc: drm CRTC 109 * 110 * Resets the atomic state for @crtc by freeing the state pointer (which might 111 * be NULL, e.g. at driver load time) and allocating a new empty state object. 112 */ 113 void drm_atomic_helper_crtc_reset(struct drm_crtc *crtc) 114 { 115 struct drm_crtc_state *crtc_state = 116 kzalloc(sizeof(*crtc->state), GFP_KERNEL); 117 118 if (crtc->state) 119 crtc->funcs->atomic_destroy_state(crtc, crtc->state); 120 121 __drm_atomic_helper_crtc_reset(crtc, crtc_state); 122 } 123 EXPORT_SYMBOL(drm_atomic_helper_crtc_reset); 124 125 /** 126 * __drm_atomic_helper_crtc_duplicate_state - copy atomic CRTC state 127 * @crtc: CRTC object 128 * @state: atomic CRTC state 129 * 130 * Copies atomic state from a CRTC's current state and resets inferred values. 131 * This is useful for drivers that subclass the CRTC state. 132 */ 133 void __drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc, 134 struct drm_crtc_state *state) 135 { 136 memcpy(state, crtc->state, sizeof(*state)); 137 138 if (state->mode_blob) 139 drm_property_blob_get(state->mode_blob); 140 if (state->degamma_lut) 141 drm_property_blob_get(state->degamma_lut); 142 if (state->ctm) 143 drm_property_blob_get(state->ctm); 144 if (state->gamma_lut) 145 drm_property_blob_get(state->gamma_lut); 146 state->mode_changed = false; 147 state->active_changed = false; 148 state->planes_changed = false; 149 state->connectors_changed = false; 150 state->color_mgmt_changed = false; 151 state->zpos_changed = false; 152 state->commit = NULL; 153 state->event = NULL; 154 state->async_flip = false; 155 156 /* Self refresh should be canceled when a new update is available */ 157 state->active = drm_atomic_crtc_effectively_active(state); 158 state->self_refresh_active = false; 159 } 160 EXPORT_SYMBOL(__drm_atomic_helper_crtc_duplicate_state); 161 162 /** 163 * drm_atomic_helper_crtc_duplicate_state - default state duplicate hook 164 * @crtc: drm CRTC 165 * 166 * Default CRTC state duplicate hook for drivers which don't have their own 167 * subclassed CRTC state structure. 168 */ 169 struct drm_crtc_state * 170 drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc) 171 { 172 struct drm_crtc_state *state; 173 174 if (WARN_ON(!crtc->state)) 175 return NULL; 176 177 state = kmalloc(sizeof(*state), GFP_KERNEL); 178 if (state) 179 __drm_atomic_helper_crtc_duplicate_state(crtc, state); 180 181 return state; 182 } 183 EXPORT_SYMBOL(drm_atomic_helper_crtc_duplicate_state); 184 185 /** 186 * __drm_atomic_helper_crtc_destroy_state - release CRTC state 187 * @state: CRTC state object to release 188 * 189 * Releases all resources stored in the CRTC state without actually freeing 190 * the memory of the CRTC state. This is useful for drivers that subclass the 191 * CRTC state. 192 */ 193 void __drm_atomic_helper_crtc_destroy_state(struct drm_crtc_state *state) 194 { 195 if (state->commit) { 196 /* 197 * In the event that a non-blocking commit returns 198 * -ERESTARTSYS before the commit_tail work is queued, we will 199 * have an extra reference to the commit object. Release it, if 200 * the event has not been consumed by the worker. 201 * 202 * state->event may be freed, so we can't directly look at 203 * state->event->base.completion. 204 */ 205 if (state->event && state->commit->abort_completion) 206 drm_crtc_commit_put(state->commit); 207 208 kfree(state->commit->event); 209 state->commit->event = NULL; 210 211 drm_crtc_commit_put(state->commit); 212 } 213 214 drm_property_blob_put(state->mode_blob); 215 drm_property_blob_put(state->degamma_lut); 216 drm_property_blob_put(state->ctm); 217 drm_property_blob_put(state->gamma_lut); 218 } 219 EXPORT_SYMBOL(__drm_atomic_helper_crtc_destroy_state); 220 221 /** 222 * drm_atomic_helper_crtc_destroy_state - default state destroy hook 223 * @crtc: drm CRTC 224 * @state: CRTC state object to release 225 * 226 * Default CRTC state destroy hook for drivers which don't have their own 227 * subclassed CRTC state structure. 228 */ 229 void drm_atomic_helper_crtc_destroy_state(struct drm_crtc *crtc, 230 struct drm_crtc_state *state) 231 { 232 __drm_atomic_helper_crtc_destroy_state(state); 233 kfree(state); 234 } 235 EXPORT_SYMBOL(drm_atomic_helper_crtc_destroy_state); 236 237 /** 238 * __drm_atomic_helper_plane_state_reset - resets plane state to default values 239 * @plane_state: atomic plane state, must not be NULL 240 * @plane: plane object, must not be NULL 241 * 242 * Initializes the newly allocated @plane_state with default 243 * values. This is useful for drivers that subclass the CRTC state. 244 */ 245 void __drm_atomic_helper_plane_state_reset(struct drm_plane_state *plane_state, 246 struct drm_plane *plane) 247 { 248 u64 val; 249 250 plane_state->plane = plane; 251 plane_state->rotation = DRM_MODE_ROTATE_0; 252 253 plane_state->alpha = DRM_BLEND_ALPHA_OPAQUE; 254 plane_state->pixel_blend_mode = DRM_MODE_BLEND_PREMULTI; 255 256 if (plane->color_encoding_property) { 257 if (!drm_object_property_get_default_value(&plane->base, 258 plane->color_encoding_property, 259 &val)) 260 plane_state->color_encoding = val; 261 } 262 263 if (plane->color_range_property) { 264 if (!drm_object_property_get_default_value(&plane->base, 265 plane->color_range_property, 266 &val)) 267 plane_state->color_range = val; 268 } 269 270 if (plane->zpos_property) { 271 if (!drm_object_property_get_default_value(&plane->base, 272 plane->zpos_property, 273 &val)) { 274 plane_state->zpos = val; 275 plane_state->normalized_zpos = val; 276 } 277 } 278 } 279 EXPORT_SYMBOL(__drm_atomic_helper_plane_state_reset); 280 281 /** 282 * __drm_atomic_helper_plane_reset - reset state on plane 283 * @plane: drm plane 284 * @plane_state: plane state to assign 285 * 286 * Initializes the newly allocated @plane_state and assigns it to 287 * the &drm_crtc->state pointer of @plane, usually required when 288 * initializing the drivers or when called from the &drm_plane_funcs.reset 289 * hook. 290 * 291 * This is useful for drivers that subclass the plane state. 292 */ 293 void __drm_atomic_helper_plane_reset(struct drm_plane *plane, 294 struct drm_plane_state *plane_state) 295 { 296 if (plane_state) 297 __drm_atomic_helper_plane_state_reset(plane_state, plane); 298 299 plane->state = plane_state; 300 } 301 EXPORT_SYMBOL(__drm_atomic_helper_plane_reset); 302 303 /** 304 * drm_atomic_helper_plane_reset - default &drm_plane_funcs.reset hook for planes 305 * @plane: drm plane 306 * 307 * Resets the atomic state for @plane by freeing the state pointer (which might 308 * be NULL, e.g. at driver load time) and allocating a new empty state object. 309 */ 310 void drm_atomic_helper_plane_reset(struct drm_plane *plane) 311 { 312 if (plane->state) 313 __drm_atomic_helper_plane_destroy_state(plane->state); 314 315 kfree(plane->state); 316 plane->state = kzalloc(sizeof(*plane->state), GFP_KERNEL); 317 if (plane->state) 318 __drm_atomic_helper_plane_reset(plane, plane->state); 319 } 320 EXPORT_SYMBOL(drm_atomic_helper_plane_reset); 321 322 /** 323 * __drm_atomic_helper_plane_duplicate_state - copy atomic plane state 324 * @plane: plane object 325 * @state: atomic plane state 326 * 327 * Copies atomic state from a plane's current state. This is useful for 328 * drivers that subclass the plane state. 329 */ 330 void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane, 331 struct drm_plane_state *state) 332 { 333 memcpy(state, plane->state, sizeof(*state)); 334 335 if (state->fb) 336 drm_framebuffer_get(state->fb); 337 338 state->fence = NULL; 339 state->commit = NULL; 340 state->fb_damage_clips = NULL; 341 } 342 EXPORT_SYMBOL(__drm_atomic_helper_plane_duplicate_state); 343 344 /** 345 * drm_atomic_helper_plane_duplicate_state - default state duplicate hook 346 * @plane: drm plane 347 * 348 * Default plane state duplicate hook for drivers which don't have their own 349 * subclassed plane state structure. 350 */ 351 struct drm_plane_state * 352 drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane) 353 { 354 struct drm_plane_state *state; 355 356 if (WARN_ON(!plane->state)) 357 return NULL; 358 359 state = kmalloc(sizeof(*state), GFP_KERNEL); 360 if (state) 361 __drm_atomic_helper_plane_duplicate_state(plane, state); 362 363 return state; 364 } 365 EXPORT_SYMBOL(drm_atomic_helper_plane_duplicate_state); 366 367 /** 368 * __drm_atomic_helper_plane_destroy_state - release plane state 369 * @state: plane state object to release 370 * 371 * Releases all resources stored in the plane state without actually freeing 372 * the memory of the plane state. This is useful for drivers that subclass the 373 * plane state. 374 */ 375 void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state) 376 { 377 if (state->fb) 378 drm_framebuffer_put(state->fb); 379 380 if (state->fence) 381 dma_fence_put(state->fence); 382 383 if (state->commit) 384 drm_crtc_commit_put(state->commit); 385 386 drm_property_blob_put(state->fb_damage_clips); 387 } 388 EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state); 389 390 /** 391 * drm_atomic_helper_plane_destroy_state - default state destroy hook 392 * @plane: drm plane 393 * @state: plane state object to release 394 * 395 * Default plane state destroy hook for drivers which don't have their own 396 * subclassed plane state structure. 397 */ 398 void drm_atomic_helper_plane_destroy_state(struct drm_plane *plane, 399 struct drm_plane_state *state) 400 { 401 __drm_atomic_helper_plane_destroy_state(state); 402 kfree(state); 403 } 404 EXPORT_SYMBOL(drm_atomic_helper_plane_destroy_state); 405 406 /** 407 * __drm_atomic_helper_connector_state_reset - reset the connector state 408 * @conn_state: atomic connector state, must not be NULL 409 * @connector: connectotr object, must not be NULL 410 * 411 * Initializes the newly allocated @conn_state with default 412 * values. This is useful for drivers that subclass the connector state. 413 */ 414 void 415 __drm_atomic_helper_connector_state_reset(struct drm_connector_state *conn_state, 416 struct drm_connector *connector) 417 { 418 conn_state->connector = connector; 419 } 420 EXPORT_SYMBOL(__drm_atomic_helper_connector_state_reset); 421 422 /** 423 * __drm_atomic_helper_connector_reset - reset state on connector 424 * @connector: drm connector 425 * @conn_state: connector state to assign 426 * 427 * Initializes the newly allocated @conn_state and assigns it to 428 * the &drm_connector->state pointer of @connector, usually required when 429 * initializing the drivers or when called from the &drm_connector_funcs.reset 430 * hook. 431 * 432 * This is useful for drivers that subclass the connector state. 433 */ 434 void 435 __drm_atomic_helper_connector_reset(struct drm_connector *connector, 436 struct drm_connector_state *conn_state) 437 { 438 if (conn_state) 439 __drm_atomic_helper_connector_state_reset(conn_state, connector); 440 441 connector->state = conn_state; 442 } 443 EXPORT_SYMBOL(__drm_atomic_helper_connector_reset); 444 445 /** 446 * drm_atomic_helper_connector_reset - default &drm_connector_funcs.reset hook for connectors 447 * @connector: drm connector 448 * 449 * Resets the atomic state for @connector by freeing the state pointer (which 450 * might be NULL, e.g. at driver load time) and allocating a new empty state 451 * object. 452 */ 453 void drm_atomic_helper_connector_reset(struct drm_connector *connector) 454 { 455 struct drm_connector_state *conn_state = 456 kzalloc(sizeof(*conn_state), GFP_KERNEL); 457 458 if (connector->state) 459 __drm_atomic_helper_connector_destroy_state(connector->state); 460 461 kfree(connector->state); 462 __drm_atomic_helper_connector_reset(connector, conn_state); 463 } 464 EXPORT_SYMBOL(drm_atomic_helper_connector_reset); 465 466 /** 467 * drm_atomic_helper_connector_tv_reset - Resets TV connector properties 468 * @connector: DRM connector 469 * 470 * Resets the TV-related properties attached to a connector. 471 */ 472 void drm_atomic_helper_connector_tv_reset(struct drm_connector *connector) 473 { 474 struct drm_cmdline_mode *cmdline = &connector->cmdline_mode; 475 struct drm_connector_state *state = connector->state; 476 477 state->tv.margins.left = cmdline->tv_margins.left; 478 state->tv.margins.right = cmdline->tv_margins.right; 479 state->tv.margins.top = cmdline->tv_margins.top; 480 state->tv.margins.bottom = cmdline->tv_margins.bottom; 481 } 482 EXPORT_SYMBOL(drm_atomic_helper_connector_tv_reset); 483 484 /** 485 * __drm_atomic_helper_connector_duplicate_state - copy atomic connector state 486 * @connector: connector object 487 * @state: atomic connector state 488 * 489 * Copies atomic state from a connector's current state. This is useful for 490 * drivers that subclass the connector state. 491 */ 492 void 493 __drm_atomic_helper_connector_duplicate_state(struct drm_connector *connector, 494 struct drm_connector_state *state) 495 { 496 memcpy(state, connector->state, sizeof(*state)); 497 if (state->crtc) 498 drm_connector_get(connector); 499 state->commit = NULL; 500 501 if (state->hdr_output_metadata) 502 drm_property_blob_get(state->hdr_output_metadata); 503 504 /* Don't copy over a writeback job, they are used only once */ 505 state->writeback_job = NULL; 506 } 507 EXPORT_SYMBOL(__drm_atomic_helper_connector_duplicate_state); 508 509 /** 510 * drm_atomic_helper_connector_duplicate_state - default state duplicate hook 511 * @connector: drm connector 512 * 513 * Default connector state duplicate hook for drivers which don't have their own 514 * subclassed connector state structure. 515 */ 516 struct drm_connector_state * 517 drm_atomic_helper_connector_duplicate_state(struct drm_connector *connector) 518 { 519 struct drm_connector_state *state; 520 521 if (WARN_ON(!connector->state)) 522 return NULL; 523 524 state = kmalloc(sizeof(*state), GFP_KERNEL); 525 if (state) 526 __drm_atomic_helper_connector_duplicate_state(connector, state); 527 528 return state; 529 } 530 EXPORT_SYMBOL(drm_atomic_helper_connector_duplicate_state); 531 532 /** 533 * __drm_atomic_helper_connector_destroy_state - release connector state 534 * @state: connector state object to release 535 * 536 * Releases all resources stored in the connector state without actually 537 * freeing the memory of the connector state. This is useful for drivers that 538 * subclass the connector state. 539 */ 540 void 541 __drm_atomic_helper_connector_destroy_state(struct drm_connector_state *state) 542 { 543 if (state->crtc) 544 drm_connector_put(state->connector); 545 546 if (state->commit) 547 drm_crtc_commit_put(state->commit); 548 549 if (state->writeback_job) 550 drm_writeback_cleanup_job(state->writeback_job); 551 552 drm_property_blob_put(state->hdr_output_metadata); 553 } 554 EXPORT_SYMBOL(__drm_atomic_helper_connector_destroy_state); 555 556 /** 557 * drm_atomic_helper_connector_destroy_state - default state destroy hook 558 * @connector: drm connector 559 * @state: connector state object to release 560 * 561 * Default connector state destroy hook for drivers which don't have their own 562 * subclassed connector state structure. 563 */ 564 void drm_atomic_helper_connector_destroy_state(struct drm_connector *connector, 565 struct drm_connector_state *state) 566 { 567 __drm_atomic_helper_connector_destroy_state(state); 568 kfree(state); 569 } 570 EXPORT_SYMBOL(drm_atomic_helper_connector_destroy_state); 571 572 /** 573 * __drm_atomic_helper_private_obj_duplicate_state - copy atomic private state 574 * @obj: CRTC object 575 * @state: new private object state 576 * 577 * Copies atomic state from a private objects's current state and resets inferred values. 578 * This is useful for drivers that subclass the private state. 579 */ 580 void __drm_atomic_helper_private_obj_duplicate_state(struct drm_private_obj *obj, 581 struct drm_private_state *state) 582 { 583 memcpy(state, obj->state, sizeof(*state)); 584 } 585 EXPORT_SYMBOL(__drm_atomic_helper_private_obj_duplicate_state); 586 587 /** 588 * __drm_atomic_helper_bridge_duplicate_state() - Copy atomic bridge state 589 * @bridge: bridge object 590 * @state: atomic bridge state 591 * 592 * Copies atomic state from a bridge's current state and resets inferred values. 593 * This is useful for drivers that subclass the bridge state. 594 */ 595 void __drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge, 596 struct drm_bridge_state *state) 597 { 598 __drm_atomic_helper_private_obj_duplicate_state(&bridge->base, 599 &state->base); 600 state->bridge = bridge; 601 } 602 EXPORT_SYMBOL(__drm_atomic_helper_bridge_duplicate_state); 603 604 /** 605 * drm_atomic_helper_bridge_duplicate_state() - Duplicate a bridge state object 606 * @bridge: bridge object 607 * 608 * Allocates a new bridge state and initializes it with the current bridge 609 * state values. This helper is meant to be used as a bridge 610 * &drm_bridge_funcs.atomic_duplicate_state hook for bridges that don't 611 * subclass the bridge state. 612 */ 613 struct drm_bridge_state * 614 drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge) 615 { 616 struct drm_bridge_state *new; 617 618 if (WARN_ON(!bridge->base.state)) 619 return NULL; 620 621 new = kzalloc(sizeof(*new), GFP_KERNEL); 622 if (new) 623 __drm_atomic_helper_bridge_duplicate_state(bridge, new); 624 625 return new; 626 } 627 EXPORT_SYMBOL(drm_atomic_helper_bridge_duplicate_state); 628 629 /** 630 * drm_atomic_helper_bridge_destroy_state() - Destroy a bridge state object 631 * @bridge: the bridge this state refers to 632 * @state: bridge state to destroy 633 * 634 * Destroys a bridge state previously created by 635 * &drm_atomic_helper_bridge_reset() or 636 * &drm_atomic_helper_bridge_duplicate_state(). This helper is meant to be 637 * used as a bridge &drm_bridge_funcs.atomic_destroy_state hook for bridges 638 * that don't subclass the bridge state. 639 */ 640 void drm_atomic_helper_bridge_destroy_state(struct drm_bridge *bridge, 641 struct drm_bridge_state *state) 642 { 643 kfree(state); 644 } 645 EXPORT_SYMBOL(drm_atomic_helper_bridge_destroy_state); 646 647 /** 648 * __drm_atomic_helper_bridge_reset() - Initialize a bridge state to its 649 * default 650 * @bridge: the bridge this state refers to 651 * @state: bridge state to initialize 652 * 653 * Initializes the bridge state to default values. This is meant to be called 654 * by the bridge &drm_bridge_funcs.atomic_reset hook for bridges that subclass 655 * the bridge state. 656 */ 657 void __drm_atomic_helper_bridge_reset(struct drm_bridge *bridge, 658 struct drm_bridge_state *state) 659 { 660 memset(state, 0, sizeof(*state)); 661 state->bridge = bridge; 662 } 663 EXPORT_SYMBOL(__drm_atomic_helper_bridge_reset); 664 665 /** 666 * drm_atomic_helper_bridge_reset() - Allocate and initialize a bridge state 667 * to its default 668 * @bridge: the bridge this state refers to 669 * 670 * Allocates the bridge state and initializes it to default values. This helper 671 * is meant to be used as a bridge &drm_bridge_funcs.atomic_reset hook for 672 * bridges that don't subclass the bridge state. 673 */ 674 struct drm_bridge_state * 675 drm_atomic_helper_bridge_reset(struct drm_bridge *bridge) 676 { 677 struct drm_bridge_state *bridge_state; 678 679 bridge_state = kzalloc(sizeof(*bridge_state), GFP_KERNEL); 680 if (!bridge_state) 681 return ERR_PTR(-ENOMEM); 682 683 __drm_atomic_helper_bridge_reset(bridge, bridge_state); 684 return bridge_state; 685 } 686 EXPORT_SYMBOL(drm_atomic_helper_bridge_reset); 687