1 /* 2 * Copyright (c) 2016 Intel Corporation 3 * 4 * Permission to use, copy, modify, distribute, and sell this software and its 5 * documentation for any purpose is hereby granted without fee, provided that 6 * the above copyright notice appear in all copies and that both that copyright 7 * notice and this permission notice appear in supporting documentation, and 8 * that the name of the copyright holders not be used in advertising or 9 * publicity pertaining to distribution of the software without specific, 10 * written prior permission. The copyright holders make no representations 11 * about the suitability of this software for any purpose. It is provided "as 12 * is" without express or implied warranty. 13 * 14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO 16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR 17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, 18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 20 * OF THIS SOFTWARE. 21 */ 22 23 #ifndef __DRM_BRIDGE_H__ 24 #define __DRM_BRIDGE_H__ 25 26 #include <linux/ctype.h> 27 #include <linux/list.h> 28 #include <linux/mutex.h> 29 30 #include <drm/drm_atomic.h> 31 #include <drm/drm_encoder.h> 32 #include <drm/drm_mode_object.h> 33 #include <drm/drm_modes.h> 34 35 struct drm_bridge; 36 struct drm_bridge_timings; 37 struct drm_connector; 38 struct drm_display_info; 39 struct drm_minor; 40 struct drm_panel; 41 struct edid; 42 struct i2c_adapter; 43 44 /** 45 * enum drm_bridge_attach_flags - Flags for &drm_bridge_funcs.attach 46 */ 47 enum drm_bridge_attach_flags { 48 /** 49 * @DRM_BRIDGE_ATTACH_NO_CONNECTOR: When this flag is set the bridge 50 * shall not create a drm_connector. 51 */ 52 DRM_BRIDGE_ATTACH_NO_CONNECTOR = BIT(0), 53 }; 54 55 /** 56 * struct drm_bridge_funcs - drm_bridge control functions 57 */ 58 struct drm_bridge_funcs { 59 /** 60 * @attach: 61 * 62 * This callback is invoked whenever our bridge is being attached to a 63 * &drm_encoder. The flags argument tunes the behaviour of the attach 64 * operation (see DRM_BRIDGE_ATTACH_*). 65 * 66 * The @attach callback is optional. 67 * 68 * RETURNS: 69 * 70 * Zero on success, error code on failure. 71 */ 72 int (*attach)(struct drm_bridge *bridge, 73 enum drm_bridge_attach_flags flags); 74 75 /** 76 * @detach: 77 * 78 * This callback is invoked whenever our bridge is being detached from a 79 * &drm_encoder. 80 * 81 * The @detach callback is optional. 82 */ 83 void (*detach)(struct drm_bridge *bridge); 84 85 /** 86 * @mode_valid: 87 * 88 * This callback is used to check if a specific mode is valid in this 89 * bridge. This should be implemented if the bridge has some sort of 90 * restriction in the modes it can display. For example, a given bridge 91 * may be responsible to set a clock value. If the clock can not 92 * produce all the values for the available modes then this callback 93 * can be used to restrict the number of modes to only the ones that 94 * can be displayed. 95 * 96 * This hook is used by the probe helpers to filter the mode list in 97 * drm_helper_probe_single_connector_modes(), and it is used by the 98 * atomic helpers to validate modes supplied by userspace in 99 * drm_atomic_helper_check_modeset(). 100 * 101 * The @mode_valid callback is optional. 102 * 103 * NOTE: 104 * 105 * Since this function is both called from the check phase of an atomic 106 * commit, and the mode validation in the probe paths it is not allowed 107 * to look at anything else but the passed-in mode, and validate it 108 * against configuration-invariant hardward constraints. Any further 109 * limits which depend upon the configuration can only be checked in 110 * @mode_fixup. 111 * 112 * RETURNS: 113 * 114 * drm_mode_status Enum 115 */ 116 enum drm_mode_status (*mode_valid)(struct drm_bridge *bridge, 117 const struct drm_display_info *info, 118 const struct drm_display_mode *mode); 119 120 /** 121 * @mode_fixup: 122 * 123 * This callback is used to validate and adjust a mode. The parameter 124 * mode is the display mode that should be fed to the next element in 125 * the display chain, either the final &drm_connector or the next 126 * &drm_bridge. The parameter adjusted_mode is the input mode the bridge 127 * requires. It can be modified by this callback and does not need to 128 * match mode. See also &drm_crtc_state.adjusted_mode for more details. 129 * 130 * This is the only hook that allows a bridge to reject a modeset. If 131 * this function passes all other callbacks must succeed for this 132 * configuration. 133 * 134 * The mode_fixup callback is optional. &drm_bridge_funcs.mode_fixup() 135 * is not called when &drm_bridge_funcs.atomic_check() is implemented, 136 * so only one of them should be provided. 137 * 138 * NOTE: 139 * 140 * This function is called in the check phase of atomic modesets, which 141 * can be aborted for any reason (including on userspace's request to 142 * just check whether a configuration would be possible). Drivers MUST 143 * NOT touch any persistent state (hardware or software) or data 144 * structures except the passed in @state parameter. 145 * 146 * Also beware that userspace can request its own custom modes, neither 147 * core nor helpers filter modes to the list of probe modes reported by 148 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure 149 * that modes are filtered consistently put any bridge constraints and 150 * limits checks into @mode_valid. 151 * 152 * RETURNS: 153 * 154 * True if an acceptable configuration is possible, false if the modeset 155 * operation should be rejected. 156 */ 157 bool (*mode_fixup)(struct drm_bridge *bridge, 158 const struct drm_display_mode *mode, 159 struct drm_display_mode *adjusted_mode); 160 /** 161 * @disable: 162 * 163 * This callback should disable the bridge. It is called right before 164 * the preceding element in the display pipe is disabled. If the 165 * preceding element is a bridge this means it's called before that 166 * bridge's @disable vfunc. If the preceding element is a &drm_encoder 167 * it's called right before the &drm_encoder_helper_funcs.disable, 168 * &drm_encoder_helper_funcs.prepare or &drm_encoder_helper_funcs.dpms 169 * hook. 170 * 171 * The bridge can assume that the display pipe (i.e. clocks and timing 172 * signals) feeding it is still running when this callback is called. 173 * 174 * The @disable callback is optional. 175 * 176 * NOTE: 177 * 178 * This is deprecated, do not use! 179 * New drivers shall use &drm_bridge_funcs.atomic_disable. 180 */ 181 void (*disable)(struct drm_bridge *bridge); 182 183 /** 184 * @post_disable: 185 * 186 * This callback should disable the bridge. It is called right after the 187 * preceding element in the display pipe is disabled. If the preceding 188 * element is a bridge this means it's called after that bridge's 189 * @post_disable function. If the preceding element is a &drm_encoder 190 * it's called right after the encoder's 191 * &drm_encoder_helper_funcs.disable, &drm_encoder_helper_funcs.prepare 192 * or &drm_encoder_helper_funcs.dpms hook. 193 * 194 * The bridge must assume that the display pipe (i.e. clocks and timing 195 * signals) feeding it is no longer running when this callback is 196 * called. 197 * 198 * The @post_disable callback is optional. 199 * 200 * NOTE: 201 * 202 * This is deprecated, do not use! 203 * New drivers shall use &drm_bridge_funcs.atomic_post_disable. 204 */ 205 void (*post_disable)(struct drm_bridge *bridge); 206 207 /** 208 * @mode_set: 209 * 210 * This callback should set the given mode on the bridge. It is called 211 * after the @mode_set callback for the preceding element in the display 212 * pipeline has been called already. If the bridge is the first element 213 * then this would be &drm_encoder_helper_funcs.mode_set. The display 214 * pipe (i.e. clocks and timing signals) is off when this function is 215 * called. 216 * 217 * The adjusted_mode parameter is the mode output by the CRTC for the 218 * first bridge in the chain. It can be different from the mode 219 * parameter that contains the desired mode for the connector at the end 220 * of the bridges chain, for instance when the first bridge in the chain 221 * performs scaling. The adjusted mode is mostly useful for the first 222 * bridge in the chain and is likely irrelevant for the other bridges. 223 * 224 * For atomic drivers the adjusted_mode is the mode stored in 225 * &drm_crtc_state.adjusted_mode. 226 * 227 * NOTE: 228 * 229 * This is deprecated, do not use! 230 * New drivers shall set their mode in the 231 * &drm_bridge_funcs.atomic_enable operation. 232 */ 233 void (*mode_set)(struct drm_bridge *bridge, 234 const struct drm_display_mode *mode, 235 const struct drm_display_mode *adjusted_mode); 236 /** 237 * @pre_enable: 238 * 239 * This callback should enable the bridge. It is called right before 240 * the preceding element in the display pipe is enabled. If the 241 * preceding element is a bridge this means it's called before that 242 * bridge's @pre_enable function. If the preceding element is a 243 * &drm_encoder it's called right before the encoder's 244 * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or 245 * &drm_encoder_helper_funcs.dpms hook. 246 * 247 * The display pipe (i.e. clocks and timing signals) feeding this bridge 248 * will not yet be running when this callback is called. The bridge must 249 * not enable the display link feeding the next bridge in the chain (if 250 * there is one) when this callback is called. 251 * 252 * The @pre_enable callback is optional. 253 * 254 * NOTE: 255 * 256 * This is deprecated, do not use! 257 * New drivers shall use &drm_bridge_funcs.atomic_pre_enable. 258 */ 259 void (*pre_enable)(struct drm_bridge *bridge); 260 261 /** 262 * @enable: 263 * 264 * This callback should enable the bridge. It is called right after 265 * the preceding element in the display pipe is enabled. If the 266 * preceding element is a bridge this means it's called after that 267 * bridge's @enable function. If the preceding element is a 268 * &drm_encoder it's called right after the encoder's 269 * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or 270 * &drm_encoder_helper_funcs.dpms hook. 271 * 272 * The bridge can assume that the display pipe (i.e. clocks and timing 273 * signals) feeding it is running when this callback is called. This 274 * callback must enable the display link feeding the next bridge in the 275 * chain if there is one. 276 * 277 * The @enable callback is optional. 278 * 279 * NOTE: 280 * 281 * This is deprecated, do not use! 282 * New drivers shall use &drm_bridge_funcs.atomic_enable. 283 */ 284 void (*enable)(struct drm_bridge *bridge); 285 286 /** 287 * @atomic_pre_enable: 288 * 289 * This callback should enable the bridge. It is called right before 290 * the preceding element in the display pipe is enabled. If the 291 * preceding element is a bridge this means it's called before that 292 * bridge's @atomic_pre_enable or @pre_enable function. If the preceding 293 * element is a &drm_encoder it's called right before the encoder's 294 * &drm_encoder_helper_funcs.atomic_enable hook. 295 * 296 * The display pipe (i.e. clocks and timing signals) feeding this bridge 297 * will not yet be running when this callback is called. The bridge must 298 * not enable the display link feeding the next bridge in the chain (if 299 * there is one) when this callback is called. 300 * 301 * The @atomic_pre_enable callback is optional. 302 */ 303 void (*atomic_pre_enable)(struct drm_bridge *bridge, 304 struct drm_bridge_state *old_bridge_state); 305 306 /** 307 * @atomic_enable: 308 * 309 * This callback should enable the bridge. It is called right after 310 * the preceding element in the display pipe is enabled. If the 311 * preceding element is a bridge this means it's called after that 312 * bridge's @atomic_enable or @enable function. If the preceding element 313 * is a &drm_encoder it's called right after the encoder's 314 * &drm_encoder_helper_funcs.atomic_enable hook. 315 * 316 * The bridge can assume that the display pipe (i.e. clocks and timing 317 * signals) feeding it is running when this callback is called. This 318 * callback must enable the display link feeding the next bridge in the 319 * chain if there is one. 320 * 321 * The @atomic_enable callback is optional. 322 */ 323 void (*atomic_enable)(struct drm_bridge *bridge, 324 struct drm_bridge_state *old_bridge_state); 325 /** 326 * @atomic_disable: 327 * 328 * This callback should disable the bridge. It is called right before 329 * the preceding element in the display pipe is disabled. If the 330 * preceding element is a bridge this means it's called before that 331 * bridge's @atomic_disable or @disable vfunc. If the preceding element 332 * is a &drm_encoder it's called right before the 333 * &drm_encoder_helper_funcs.atomic_disable hook. 334 * 335 * The bridge can assume that the display pipe (i.e. clocks and timing 336 * signals) feeding it is still running when this callback is called. 337 * 338 * The @atomic_disable callback is optional. 339 */ 340 void (*atomic_disable)(struct drm_bridge *bridge, 341 struct drm_bridge_state *old_bridge_state); 342 343 /** 344 * @atomic_post_disable: 345 * 346 * This callback should disable the bridge. It is called right after the 347 * preceding element in the display pipe is disabled. If the preceding 348 * element is a bridge this means it's called after that bridge's 349 * @atomic_post_disable or @post_disable function. If the preceding 350 * element is a &drm_encoder it's called right after the encoder's 351 * &drm_encoder_helper_funcs.atomic_disable hook. 352 * 353 * The bridge must assume that the display pipe (i.e. clocks and timing 354 * signals) feeding it is no longer running when this callback is 355 * called. 356 * 357 * The @atomic_post_disable callback is optional. 358 */ 359 void (*atomic_post_disable)(struct drm_bridge *bridge, 360 struct drm_bridge_state *old_bridge_state); 361 362 /** 363 * @atomic_duplicate_state: 364 * 365 * Duplicate the current bridge state object (which is guaranteed to be 366 * non-NULL). 367 * 368 * The atomic_duplicate_state hook is mandatory if the bridge 369 * implements any of the atomic hooks, and should be left unassigned 370 * otherwise. For bridges that don't subclass &drm_bridge_state, the 371 * drm_atomic_helper_bridge_duplicate_state() helper function shall be 372 * used to implement this hook. 373 * 374 * RETURNS: 375 * A valid drm_bridge_state object or NULL if the allocation fails. 376 */ 377 struct drm_bridge_state *(*atomic_duplicate_state)(struct drm_bridge *bridge); 378 379 /** 380 * @atomic_destroy_state: 381 * 382 * Destroy a bridge state object previously allocated by 383 * &drm_bridge_funcs.atomic_duplicate_state(). 384 * 385 * The atomic_destroy_state hook is mandatory if the bridge implements 386 * any of the atomic hooks, and should be left unassigned otherwise. 387 * For bridges that don't subclass &drm_bridge_state, the 388 * drm_atomic_helper_bridge_destroy_state() helper function shall be 389 * used to implement this hook. 390 */ 391 void (*atomic_destroy_state)(struct drm_bridge *bridge, 392 struct drm_bridge_state *state); 393 394 /** 395 * @atomic_get_output_bus_fmts: 396 * 397 * Return the supported bus formats on the output end of a bridge. 398 * The returned array must be allocated with kmalloc() and will be 399 * freed by the caller. If the allocation fails, NULL should be 400 * returned. num_output_fmts must be set to the returned array size. 401 * Formats listed in the returned array should be listed in decreasing 402 * preference order (the core will try all formats until it finds one 403 * that works). 404 * 405 * This method is only called on the last element of the bridge chain 406 * as part of the bus format negotiation process that happens in 407 * &drm_atomic_bridge_chain_select_bus_fmts(). 408 * This method is optional. When not implemented, the core will 409 * fall back to &drm_connector.display_info.bus_formats[0] if 410 * &drm_connector.display_info.num_bus_formats > 0, 411 * or to MEDIA_BUS_FMT_FIXED otherwise. 412 */ 413 u32 *(*atomic_get_output_bus_fmts)(struct drm_bridge *bridge, 414 struct drm_bridge_state *bridge_state, 415 struct drm_crtc_state *crtc_state, 416 struct drm_connector_state *conn_state, 417 unsigned int *num_output_fmts); 418 419 /** 420 * @atomic_get_input_bus_fmts: 421 * 422 * Return the supported bus formats on the input end of a bridge for 423 * a specific output bus format. 424 * 425 * The returned array must be allocated with kmalloc() and will be 426 * freed by the caller. If the allocation fails, NULL should be 427 * returned. num_input_fmts must be set to the returned array size. 428 * Formats listed in the returned array should be listed in decreasing 429 * preference order (the core will try all formats until it finds one 430 * that works). When the format is not supported NULL should be 431 * returned and num_input_fmts should be set to 0. 432 * 433 * This method is called on all elements of the bridge chain as part of 434 * the bus format negotiation process that happens in 435 * drm_atomic_bridge_chain_select_bus_fmts(). 436 * This method is optional. When not implemented, the core will bypass 437 * bus format negotiation on this element of the bridge without 438 * failing, and the previous element in the chain will be passed 439 * MEDIA_BUS_FMT_FIXED as its output bus format. 440 * 441 * Bridge drivers that need to support being linked to bridges that are 442 * not supporting bus format negotiation should handle the 443 * output_fmt == MEDIA_BUS_FMT_FIXED case appropriately, by selecting a 444 * sensible default value or extracting this information from somewhere 445 * else (FW property, &drm_display_mode, &drm_display_info, ...) 446 * 447 * Note: Even if input format selection on the first bridge has no 448 * impact on the negotiation process (bus format negotiation stops once 449 * we reach the first element of the chain), drivers are expected to 450 * return accurate input formats as the input format may be used to 451 * configure the CRTC output appropriately. 452 */ 453 u32 *(*atomic_get_input_bus_fmts)(struct drm_bridge *bridge, 454 struct drm_bridge_state *bridge_state, 455 struct drm_crtc_state *crtc_state, 456 struct drm_connector_state *conn_state, 457 u32 output_fmt, 458 unsigned int *num_input_fmts); 459 460 /** 461 * @atomic_check: 462 * 463 * This method is responsible for checking bridge state correctness. 464 * It can also check the state of the surrounding components in chain 465 * to make sure the whole pipeline can work properly. 466 * 467 * &drm_bridge_funcs.atomic_check() hooks are called in reverse 468 * order (from the last to the first bridge). 469 * 470 * This method is optional. &drm_bridge_funcs.mode_fixup() is not 471 * called when &drm_bridge_funcs.atomic_check() is implemented, so only 472 * one of them should be provided. 473 * 474 * If drivers need to tweak &drm_bridge_state.input_bus_cfg.flags or 475 * &drm_bridge_state.output_bus_cfg.flags it should happen in 476 * this function. By default the &drm_bridge_state.output_bus_cfg.flags 477 * field is set to the next bridge 478 * &drm_bridge_state.input_bus_cfg.flags value or 479 * &drm_connector.display_info.bus_flags if the bridge is the last 480 * element in the chain. 481 * 482 * RETURNS: 483 * zero if the check passed, a negative error code otherwise. 484 */ 485 int (*atomic_check)(struct drm_bridge *bridge, 486 struct drm_bridge_state *bridge_state, 487 struct drm_crtc_state *crtc_state, 488 struct drm_connector_state *conn_state); 489 490 /** 491 * @atomic_reset: 492 * 493 * Reset the bridge to a predefined state (or retrieve its current 494 * state) and return a &drm_bridge_state object matching this state. 495 * This function is called at attach time. 496 * 497 * The atomic_reset hook is mandatory if the bridge implements any of 498 * the atomic hooks, and should be left unassigned otherwise. For 499 * bridges that don't subclass &drm_bridge_state, the 500 * drm_atomic_helper_bridge_reset() helper function shall be used to 501 * implement this hook. 502 * 503 * Note that the atomic_reset() semantics is not exactly matching the 504 * reset() semantics found on other components (connector, plane, ...). 505 * 506 * 1. The reset operation happens when the bridge is attached, not when 507 * drm_mode_config_reset() is called 508 * 2. It's meant to be used exclusively on bridges that have been 509 * converted to the ATOMIC API 510 * 511 * RETURNS: 512 * A valid drm_bridge_state object in case of success, an ERR_PTR() 513 * giving the reason of the failure otherwise. 514 */ 515 struct drm_bridge_state *(*atomic_reset)(struct drm_bridge *bridge); 516 517 /** 518 * @detect: 519 * 520 * Check if anything is attached to the bridge output. 521 * 522 * This callback is optional, if not implemented the bridge will be 523 * considered as always having a component attached to its output. 524 * Bridges that implement this callback shall set the 525 * DRM_BRIDGE_OP_DETECT flag in their &drm_bridge->ops. 526 * 527 * RETURNS: 528 * 529 * drm_connector_status indicating the bridge output status. 530 */ 531 enum drm_connector_status (*detect)(struct drm_bridge *bridge); 532 533 /** 534 * @get_modes: 535 * 536 * Fill all modes currently valid for the sink into the &drm_connector 537 * with drm_mode_probed_add(). 538 * 539 * The @get_modes callback is mostly intended to support non-probeable 540 * displays such as many fixed panels. Bridges that support reading 541 * EDID shall leave @get_modes unimplemented and implement the 542 * &drm_bridge_funcs->get_edid callback instead. 543 * 544 * This callback is optional. Bridges that implement it shall set the 545 * DRM_BRIDGE_OP_MODES flag in their &drm_bridge->ops. 546 * 547 * The connector parameter shall be used for the sole purpose of 548 * filling modes, and shall not be stored internally by bridge drivers 549 * for future usage. 550 * 551 * RETURNS: 552 * 553 * The number of modes added by calling drm_mode_probed_add(). 554 */ 555 int (*get_modes)(struct drm_bridge *bridge, 556 struct drm_connector *connector); 557 558 /** 559 * @edid_read: 560 * 561 * Read the EDID data of the connected display. 562 * 563 * The @edid_read callback is the preferred way of reporting mode 564 * information for a display connected to the bridge output. Bridges 565 * that support reading EDID shall implement this callback and leave 566 * the @get_modes callback unimplemented. 567 * 568 * The caller of this operation shall first verify the output 569 * connection status and refrain from reading EDID from a disconnected 570 * output. 571 * 572 * This callback is optional. Bridges that implement it shall set the 573 * DRM_BRIDGE_OP_EDID flag in their &drm_bridge->ops. 574 * 575 * The connector parameter shall be used for the sole purpose of EDID 576 * retrieval, and shall not be stored internally by bridge drivers for 577 * future usage. 578 * 579 * RETURNS: 580 * 581 * An edid structure newly allocated with drm_edid_alloc() or returned 582 * from drm_edid_read() family of functions on success, or NULL 583 * otherwise. The caller is responsible for freeing the returned edid 584 * structure with drm_edid_free(). 585 */ 586 const struct drm_edid *(*edid_read)(struct drm_bridge *bridge, 587 struct drm_connector *connector); 588 589 /** 590 * @get_edid: 591 * 592 * Read and parse the EDID data of the connected display. 593 * 594 * The @get_edid callback is the preferred way of reporting mode 595 * information for a display connected to the bridge output. Bridges 596 * that support reading EDID shall implement this callback and leave 597 * the @get_modes callback unimplemented. 598 * 599 * The caller of this operation shall first verify the output 600 * connection status and refrain from reading EDID from a disconnected 601 * output. 602 * 603 * This callback is optional. Bridges that implement it shall set the 604 * DRM_BRIDGE_OP_EDID flag in their &drm_bridge->ops. 605 * 606 * The connector parameter shall be used for the sole purpose of EDID 607 * retrieval and parsing, and shall not be stored internally by bridge 608 * drivers for future usage. 609 * 610 * RETURNS: 611 * 612 * An edid structure newly allocated with kmalloc() (or similar) on 613 * success, or NULL otherwise. The caller is responsible for freeing 614 * the returned edid structure with kfree(). 615 */ 616 struct edid *(*get_edid)(struct drm_bridge *bridge, 617 struct drm_connector *connector); 618 619 /** 620 * @hpd_notify: 621 * 622 * Notify the bridge of hot plug detection. 623 * 624 * This callback is optional, it may be implemented by bridges that 625 * need to be notified of display connection or disconnection for 626 * internal reasons. One use case is to reset the internal state of CEC 627 * controllers for HDMI bridges. 628 */ 629 void (*hpd_notify)(struct drm_bridge *bridge, 630 enum drm_connector_status status); 631 632 /** 633 * @hpd_enable: 634 * 635 * Enable hot plug detection. From now on the bridge shall call 636 * drm_bridge_hpd_notify() each time a change is detected in the output 637 * connection status, until hot plug detection gets disabled with 638 * @hpd_disable. 639 * 640 * This callback is optional and shall only be implemented by bridges 641 * that support hot-plug notification without polling. Bridges that 642 * implement it shall also implement the @hpd_disable callback and set 643 * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops. 644 */ 645 void (*hpd_enable)(struct drm_bridge *bridge); 646 647 /** 648 * @hpd_disable: 649 * 650 * Disable hot plug detection. Once this function returns the bridge 651 * shall not call drm_bridge_hpd_notify() when a change in the output 652 * connection status occurs. 653 * 654 * This callback is optional and shall only be implemented by bridges 655 * that support hot-plug notification without polling. Bridges that 656 * implement it shall also implement the @hpd_enable callback and set 657 * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops. 658 */ 659 void (*hpd_disable)(struct drm_bridge *bridge); 660 661 /** 662 * @debugfs_init: 663 * 664 * Allows bridges to create bridge-specific debugfs files. 665 */ 666 void (*debugfs_init)(struct drm_bridge *bridge, struct dentry *root); 667 }; 668 669 /** 670 * struct drm_bridge_timings - timing information for the bridge 671 */ 672 struct drm_bridge_timings { 673 /** 674 * @input_bus_flags: 675 * 676 * Tells what additional settings for the pixel data on the bus 677 * this bridge requires (like pixel signal polarity). See also 678 * &drm_display_info->bus_flags. 679 */ 680 u32 input_bus_flags; 681 /** 682 * @setup_time_ps: 683 * 684 * Defines the time in picoseconds the input data lines must be 685 * stable before the clock edge. 686 */ 687 u32 setup_time_ps; 688 /** 689 * @hold_time_ps: 690 * 691 * Defines the time in picoseconds taken for the bridge to sample the 692 * input signal after the clock edge. 693 */ 694 u32 hold_time_ps; 695 /** 696 * @dual_link: 697 * 698 * True if the bus operates in dual-link mode. The exact meaning is 699 * dependent on the bus type. For LVDS buses, this indicates that even- 700 * and odd-numbered pixels are received on separate links. 701 */ 702 bool dual_link; 703 }; 704 705 /** 706 * enum drm_bridge_ops - Bitmask of operations supported by the bridge 707 */ 708 enum drm_bridge_ops { 709 /** 710 * @DRM_BRIDGE_OP_DETECT: The bridge can detect displays connected to 711 * its output. Bridges that set this flag shall implement the 712 * &drm_bridge_funcs->detect callback. 713 */ 714 DRM_BRIDGE_OP_DETECT = BIT(0), 715 /** 716 * @DRM_BRIDGE_OP_EDID: The bridge can retrieve the EDID of the display 717 * connected to its output. Bridges that set this flag shall implement 718 * the &drm_bridge_funcs->get_edid callback. 719 */ 720 DRM_BRIDGE_OP_EDID = BIT(1), 721 /** 722 * @DRM_BRIDGE_OP_HPD: The bridge can detect hot-plug and hot-unplug 723 * without requiring polling. Bridges that set this flag shall 724 * implement the &drm_bridge_funcs->hpd_enable and 725 * &drm_bridge_funcs->hpd_disable callbacks if they support enabling 726 * and disabling hot-plug detection dynamically. 727 */ 728 DRM_BRIDGE_OP_HPD = BIT(2), 729 /** 730 * @DRM_BRIDGE_OP_MODES: The bridge can retrieve the modes supported 731 * by the display at its output. This does not include reading EDID 732 * which is separately covered by @DRM_BRIDGE_OP_EDID. Bridges that set 733 * this flag shall implement the &drm_bridge_funcs->get_modes callback. 734 */ 735 DRM_BRIDGE_OP_MODES = BIT(3), 736 }; 737 738 /** 739 * struct drm_bridge - central DRM bridge control structure 740 */ 741 struct drm_bridge { 742 /** @base: inherit from &drm_private_object */ 743 struct drm_private_obj base; 744 /** @dev: DRM device this bridge belongs to */ 745 struct drm_device *dev; 746 /** @encoder: encoder to which this bridge is connected */ 747 struct drm_encoder *encoder; 748 /** @chain_node: used to form a bridge chain */ 749 struct list_head chain_node; 750 #ifdef CONFIG_OF 751 /** @of_node: device node pointer to the bridge */ 752 struct device_node *of_node; 753 #endif 754 /** @list: to keep track of all added bridges */ 755 struct list_head list; 756 /** 757 * @timings: 758 * 759 * the timing specification for the bridge, if any (may be NULL) 760 */ 761 const struct drm_bridge_timings *timings; 762 /** @funcs: control functions */ 763 const struct drm_bridge_funcs *funcs; 764 /** @driver_private: pointer to the bridge driver's internal context */ 765 void *driver_private; 766 /** @ops: bitmask of operations supported by the bridge */ 767 enum drm_bridge_ops ops; 768 /** 769 * @type: Type of the connection at the bridge output 770 * (DRM_MODE_CONNECTOR_*). For bridges at the end of this chain this 771 * identifies the type of connected display. 772 */ 773 int type; 774 /** 775 * @interlace_allowed: Indicate that the bridge can handle interlaced 776 * modes. 777 */ 778 bool interlace_allowed; 779 /** 780 * @pre_enable_prev_first: The bridge requires that the prev 781 * bridge @pre_enable function is called before its @pre_enable, 782 * and conversely for post_disable. This is most frequently a 783 * requirement for DSI devices which need the host to be initialised 784 * before the peripheral. 785 */ 786 bool pre_enable_prev_first; 787 /** 788 * @ddc: Associated I2C adapter for DDC access, if any. 789 */ 790 struct i2c_adapter *ddc; 791 /** private: */ 792 /** 793 * @hpd_mutex: Protects the @hpd_cb and @hpd_data fields. 794 */ 795 struct mutex hpd_mutex; 796 /** 797 * @hpd_cb: Hot plug detection callback, registered with 798 * drm_bridge_hpd_enable(). 799 */ 800 void (*hpd_cb)(void *data, enum drm_connector_status status); 801 /** 802 * @hpd_data: Private data passed to the Hot plug detection callback 803 * @hpd_cb. 804 */ 805 void *hpd_data; 806 }; 807 808 static inline struct drm_bridge * 809 drm_priv_to_bridge(struct drm_private_obj *priv) 810 { 811 return container_of(priv, struct drm_bridge, base); 812 } 813 814 void drm_bridge_add(struct drm_bridge *bridge); 815 int devm_drm_bridge_add(struct device *dev, struct drm_bridge *bridge); 816 void drm_bridge_remove(struct drm_bridge *bridge); 817 int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge, 818 struct drm_bridge *previous, 819 enum drm_bridge_attach_flags flags); 820 821 #ifdef CONFIG_OF 822 struct drm_bridge *of_drm_find_bridge(struct device_node *np); 823 #else 824 static inline struct drm_bridge *of_drm_find_bridge(struct device_node *np) 825 { 826 return NULL; 827 } 828 #endif 829 830 /** 831 * drm_bridge_get_next_bridge() - Get the next bridge in the chain 832 * @bridge: bridge object 833 * 834 * RETURNS: 835 * the next bridge in the chain after @bridge, or NULL if @bridge is the last. 836 */ 837 static inline struct drm_bridge * 838 drm_bridge_get_next_bridge(struct drm_bridge *bridge) 839 { 840 if (list_is_last(&bridge->chain_node, &bridge->encoder->bridge_chain)) 841 return NULL; 842 843 return list_next_entry(bridge, chain_node); 844 } 845 846 /** 847 * drm_bridge_get_prev_bridge() - Get the previous bridge in the chain 848 * @bridge: bridge object 849 * 850 * RETURNS: 851 * the previous bridge in the chain, or NULL if @bridge is the first. 852 */ 853 static inline struct drm_bridge * 854 drm_bridge_get_prev_bridge(struct drm_bridge *bridge) 855 { 856 if (list_is_first(&bridge->chain_node, &bridge->encoder->bridge_chain)) 857 return NULL; 858 859 return list_prev_entry(bridge, chain_node); 860 } 861 862 /** 863 * drm_bridge_chain_get_first_bridge() - Get the first bridge in the chain 864 * @encoder: encoder object 865 * 866 * RETURNS: 867 * the first bridge in the chain, or NULL if @encoder has no bridge attached 868 * to it. 869 */ 870 static inline struct drm_bridge * 871 drm_bridge_chain_get_first_bridge(struct drm_encoder *encoder) 872 { 873 return list_first_entry_or_null(&encoder->bridge_chain, 874 struct drm_bridge, chain_node); 875 } 876 877 /** 878 * drm_for_each_bridge_in_chain() - Iterate over all bridges present in a chain 879 * @encoder: the encoder to iterate bridges on 880 * @bridge: a bridge pointer updated to point to the current bridge at each 881 * iteration 882 * 883 * Iterate over all bridges present in the bridge chain attached to @encoder. 884 */ 885 #define drm_for_each_bridge_in_chain(encoder, bridge) \ 886 list_for_each_entry(bridge, &(encoder)->bridge_chain, chain_node) 887 888 bool drm_bridge_chain_mode_fixup(struct drm_bridge *bridge, 889 const struct drm_display_mode *mode, 890 struct drm_display_mode *adjusted_mode); 891 enum drm_mode_status 892 drm_bridge_chain_mode_valid(struct drm_bridge *bridge, 893 const struct drm_display_info *info, 894 const struct drm_display_mode *mode); 895 void drm_bridge_chain_mode_set(struct drm_bridge *bridge, 896 const struct drm_display_mode *mode, 897 const struct drm_display_mode *adjusted_mode); 898 899 int drm_atomic_bridge_chain_check(struct drm_bridge *bridge, 900 struct drm_crtc_state *crtc_state, 901 struct drm_connector_state *conn_state); 902 void drm_atomic_bridge_chain_disable(struct drm_bridge *bridge, 903 struct drm_atomic_state *state); 904 void drm_atomic_bridge_chain_post_disable(struct drm_bridge *bridge, 905 struct drm_atomic_state *state); 906 void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge, 907 struct drm_atomic_state *state); 908 void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge, 909 struct drm_atomic_state *state); 910 911 u32 * 912 drm_atomic_helper_bridge_propagate_bus_fmt(struct drm_bridge *bridge, 913 struct drm_bridge_state *bridge_state, 914 struct drm_crtc_state *crtc_state, 915 struct drm_connector_state *conn_state, 916 u32 output_fmt, 917 unsigned int *num_input_fmts); 918 919 enum drm_connector_status drm_bridge_detect(struct drm_bridge *bridge); 920 int drm_bridge_get_modes(struct drm_bridge *bridge, 921 struct drm_connector *connector); 922 const struct drm_edid *drm_bridge_edid_read(struct drm_bridge *bridge, 923 struct drm_connector *connector); 924 struct edid *drm_bridge_get_edid(struct drm_bridge *bridge, 925 struct drm_connector *connector); 926 void drm_bridge_hpd_enable(struct drm_bridge *bridge, 927 void (*cb)(void *data, 928 enum drm_connector_status status), 929 void *data); 930 void drm_bridge_hpd_disable(struct drm_bridge *bridge); 931 void drm_bridge_hpd_notify(struct drm_bridge *bridge, 932 enum drm_connector_status status); 933 934 #ifdef CONFIG_DRM_PANEL_BRIDGE 935 bool drm_bridge_is_panel(const struct drm_bridge *bridge); 936 struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel); 937 struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel, 938 u32 connector_type); 939 void drm_panel_bridge_remove(struct drm_bridge *bridge); 940 int drm_panel_bridge_set_orientation(struct drm_connector *connector, 941 struct drm_bridge *bridge); 942 struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev, 943 struct drm_panel *panel); 944 struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev, 945 struct drm_panel *panel, 946 u32 connector_type); 947 struct drm_bridge *drmm_panel_bridge_add(struct drm_device *drm, 948 struct drm_panel *panel); 949 struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge); 950 #else 951 static inline bool drm_bridge_is_panel(const struct drm_bridge *bridge) 952 { 953 return false; 954 } 955 956 static inline int drm_panel_bridge_set_orientation(struct drm_connector *connector, 957 struct drm_bridge *bridge) 958 { 959 return -EINVAL; 960 } 961 #endif 962 963 #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL_BRIDGE) 964 struct drm_bridge *devm_drm_of_get_bridge(struct device *dev, struct device_node *node, 965 u32 port, u32 endpoint); 966 struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm, struct device_node *node, 967 u32 port, u32 endpoint); 968 #else 969 static inline struct drm_bridge *devm_drm_of_get_bridge(struct device *dev, 970 struct device_node *node, 971 u32 port, 972 u32 endpoint) 973 { 974 return ERR_PTR(-ENODEV); 975 } 976 977 static inline struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm, 978 struct device_node *node, 979 u32 port, 980 u32 endpoint) 981 { 982 return ERR_PTR(-ENODEV); 983 } 984 #endif 985 986 void drm_bridge_debugfs_init(struct drm_minor *minor); 987 988 #endif 989