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