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