1 /* 2 * Copyright (c) 2006-2008 Intel Corporation 3 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie> 4 * 5 * DRM core CRTC related functions 6 * 7 * Permission to use, copy, modify, distribute, and sell this software and its 8 * documentation for any purpose is hereby granted without fee, provided that 9 * the above copyright notice appear in all copies and that both that copyright 10 * notice and this permission notice appear in supporting documentation, and 11 * that the name of the copyright holders not be used in advertising or 12 * publicity pertaining to distribution of the software without specific, 13 * written prior permission. The copyright holders make no representations 14 * about the suitability of this software for any purpose. It is provided "as 15 * is" without express or implied warranty. 16 * 17 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 18 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO 19 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR 20 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, 21 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 22 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 23 * OF THIS SOFTWARE. 24 * 25 * Authors: 26 * Keith Packard 27 * Eric Anholt <eric@anholt.net> 28 * Dave Airlie <airlied@linux.ie> 29 * Jesse Barnes <jesse.barnes@intel.com> 30 */ 31 32 #include <linux/export.h> 33 #include <linux/moduleparam.h> 34 35 #include <drm/drmP.h> 36 #include <drm/drm_crtc.h> 37 #include <drm/drm_fourcc.h> 38 #include <drm/drm_crtc_helper.h> 39 #include <drm/drm_fb_helper.h> 40 #include <drm/drm_edid.h> 41 42 /** 43 * DOC: output probing helper overview 44 * 45 * This library provides some helper code for output probing. It provides an 46 * implementation of the core connector->fill_modes interface with 47 * drm_helper_probe_single_connector_modes. 48 * 49 * It also provides support for polling connectors with a work item and for 50 * generic hotplug interrupt handling where the driver doesn't or cannot keep 51 * track of a per-connector hpd interrupt. 52 * 53 * This helper library can be used independently of the modeset helper library. 54 * Drivers can also overwrite different parts e.g. use their own hotplug 55 * handling code to avoid probing unrelated outputs. 56 * 57 * The probe helpers share the function table structures with other display 58 * helper libraries. See struct &drm_connector_helper_funcs for the details. 59 */ 60 61 static bool drm_kms_helper_poll = true; 62 module_param_named(poll, drm_kms_helper_poll, bool, 0600); 63 64 static enum drm_mode_status 65 drm_mode_validate_flag(const struct drm_display_mode *mode, 66 int flags) 67 { 68 if ((mode->flags & DRM_MODE_FLAG_INTERLACE) && 69 !(flags & DRM_MODE_FLAG_INTERLACE)) 70 return MODE_NO_INTERLACE; 71 72 if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) && 73 !(flags & DRM_MODE_FLAG_DBLSCAN)) 74 return MODE_NO_DBLESCAN; 75 76 if ((mode->flags & DRM_MODE_FLAG_3D_MASK) && 77 !(flags & DRM_MODE_FLAG_3D_MASK)) 78 return MODE_NO_STEREO; 79 80 return MODE_OK; 81 } 82 83 static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector) 84 { 85 struct drm_cmdline_mode *cmdline_mode; 86 struct drm_display_mode *mode; 87 88 cmdline_mode = &connector->cmdline_mode; 89 if (!cmdline_mode->specified) 90 return 0; 91 92 /* Only add a GTF mode if we find no matching probed modes */ 93 list_for_each_entry(mode, &connector->probed_modes, head) { 94 if (mode->hdisplay != cmdline_mode->xres || 95 mode->vdisplay != cmdline_mode->yres) 96 continue; 97 98 if (cmdline_mode->refresh_specified) { 99 /* The probed mode's vrefresh is set until later */ 100 if (drm_mode_vrefresh(mode) != cmdline_mode->refresh) 101 continue; 102 } 103 104 return 0; 105 } 106 107 mode = drm_mode_create_from_cmdline_mode(connector->dev, 108 cmdline_mode); 109 if (mode == NULL) 110 return 0; 111 112 drm_mode_probed_add(connector, mode); 113 return 1; 114 } 115 116 #define DRM_OUTPUT_POLL_PERIOD (10*HZ) 117 /** 118 * drm_kms_helper_poll_enable_locked - re-enable output polling. 119 * @dev: drm_device 120 * 121 * This function re-enables the output polling work without 122 * locking the mode_config mutex. 123 * 124 * This is like drm_kms_helper_poll_enable() however it is to be 125 * called from a context where the mode_config mutex is locked 126 * already. 127 */ 128 void drm_kms_helper_poll_enable_locked(struct drm_device *dev) 129 { 130 bool poll = false; 131 struct drm_connector *connector; 132 unsigned long delay = DRM_OUTPUT_POLL_PERIOD; 133 134 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex)); 135 136 if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll) 137 return; 138 139 drm_for_each_connector(connector, dev) { 140 if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT | 141 DRM_CONNECTOR_POLL_DISCONNECT)) 142 poll = true; 143 } 144 145 if (dev->mode_config.delayed_event) { 146 /* 147 * FIXME: 148 * 149 * Use short (1s) delay to handle the initial delayed event. 150 * This delay should not be needed, but Optimus/nouveau will 151 * fail in a mysterious way if the delayed event is handled as 152 * soon as possible like it is done in 153 * drm_helper_probe_single_connector_modes() in case the poll 154 * was enabled before. 155 */ 156 poll = true; 157 delay = HZ; 158 } 159 160 if (poll) 161 schedule_delayed_work(&dev->mode_config.output_poll_work, delay); 162 } 163 EXPORT_SYMBOL(drm_kms_helper_poll_enable_locked); 164 165 static enum drm_connector_status 166 drm_connector_detect(struct drm_connector *connector, bool force) 167 { 168 return connector->funcs->detect ? 169 connector->funcs->detect(connector, force) : 170 connector_status_connected; 171 } 172 173 /** 174 * drm_helper_probe_single_connector_modes - get complete set of display modes 175 * @connector: connector to probe 176 * @maxX: max width for modes 177 * @maxY: max height for modes 178 * 179 * Based on the helper callbacks implemented by @connector in struct 180 * &drm_connector_helper_funcs try to detect all valid modes. Modes will first 181 * be added to the connector's probed_modes list, then culled (based on validity 182 * and the @maxX, @maxY parameters) and put into the normal modes list. 183 * 184 * Intended to be used as a generic implementation of the ->fill_modes() 185 * @connector vfunc for drivers that use the CRTC helpers for output mode 186 * filtering and detection. 187 * 188 * The basic procedure is as follows 189 * 190 * 1. All modes currently on the connector's modes list are marked as stale 191 * 192 * 2. New modes are added to the connector's probed_modes list with 193 * drm_mode_probed_add(). New modes start their life with status as OK. 194 * Modes are added from a single source using the following priority order. 195 * 196 * - debugfs 'override_edid' (used for testing only) 197 * - firmware EDID (drm_load_edid_firmware()) 198 * - connector helper ->get_modes() vfunc 199 * - if the connector status is connector_status_connected, standard 200 * VESA DMT modes up to 1024x768 are automatically added 201 * (drm_add_modes_noedid()) 202 * 203 * Finally modes specified via the kernel command line (video=...) are 204 * added in addition to what the earlier probes produced 205 * (drm_helper_probe_add_cmdline_mode()). These modes are generated 206 * using the VESA GTF/CVT formulas. 207 * 208 * 3. Modes are moved from the probed_modes list to the modes list. Potential 209 * duplicates are merged together (see drm_mode_connector_list_update()). 210 * After this step the probed_modes list will be empty again. 211 * 212 * 4. Any non-stale mode on the modes list then undergoes validation 213 * 214 * - drm_mode_validate_basic() performs basic sanity checks 215 * - drm_mode_validate_size() filters out modes larger than @maxX and @maxY 216 * (if specified) 217 * - drm_mode_validate_flag() checks the modes againt basic connector 218 * capabilites (interlace_allowed,doublescan_allowed,stereo_allowed) 219 * - the optional connector ->mode_valid() helper can perform driver and/or 220 * hardware specific checks 221 * 222 * 5. Any mode whose status is not OK is pruned from the connector's modes list, 223 * accompanied by a debug message indicating the reason for the mode's 224 * rejection (see drm_mode_prune_invalid()). 225 * 226 * Returns: 227 * The number of modes found on @connector. 228 */ 229 int drm_helper_probe_single_connector_modes(struct drm_connector *connector, 230 uint32_t maxX, uint32_t maxY) 231 { 232 struct drm_device *dev = connector->dev; 233 struct drm_display_mode *mode; 234 const struct drm_connector_helper_funcs *connector_funcs = 235 connector->helper_private; 236 int count = 0; 237 int mode_flags = 0; 238 bool verbose_prune = true; 239 enum drm_connector_status old_status; 240 241 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex)); 242 243 DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id, 244 connector->name); 245 /* set all old modes to the stale state */ 246 list_for_each_entry(mode, &connector->modes, head) 247 mode->status = MODE_STALE; 248 249 old_status = connector->status; 250 251 if (connector->force) { 252 if (connector->force == DRM_FORCE_ON || 253 connector->force == DRM_FORCE_ON_DIGITAL) 254 connector->status = connector_status_connected; 255 else 256 connector->status = connector_status_disconnected; 257 if (connector->funcs->force) 258 connector->funcs->force(connector); 259 } else { 260 connector->status = drm_connector_detect(connector, true); 261 } 262 263 /* 264 * Normally either the driver's hpd code or the poll loop should 265 * pick up any changes and fire the hotplug event. But if 266 * userspace sneaks in a probe, we might miss a change. Hence 267 * check here, and if anything changed start the hotplug code. 268 */ 269 if (old_status != connector->status) { 270 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n", 271 connector->base.id, 272 connector->name, 273 drm_get_connector_status_name(old_status), 274 drm_get_connector_status_name(connector->status)); 275 276 /* 277 * The hotplug event code might call into the fb 278 * helpers, and so expects that we do not hold any 279 * locks. Fire up the poll struct instead, it will 280 * disable itself again. 281 */ 282 dev->mode_config.delayed_event = true; 283 if (dev->mode_config.poll_enabled) 284 schedule_delayed_work(&dev->mode_config.output_poll_work, 285 0); 286 } 287 288 /* Re-enable polling in case the global poll config changed. */ 289 if (drm_kms_helper_poll != dev->mode_config.poll_running) 290 drm_kms_helper_poll_enable_locked(dev); 291 292 dev->mode_config.poll_running = drm_kms_helper_poll; 293 294 if (connector->status == connector_status_disconnected) { 295 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n", 296 connector->base.id, connector->name); 297 drm_mode_connector_update_edid_property(connector, NULL); 298 verbose_prune = false; 299 goto prune; 300 } 301 302 if (connector->override_edid) { 303 struct edid *edid = (struct edid *) connector->edid_blob_ptr->data; 304 305 count = drm_add_edid_modes(connector, edid); 306 drm_edid_to_eld(connector, edid); 307 } else { 308 count = drm_load_edid_firmware(connector); 309 if (count == 0) 310 count = (*connector_funcs->get_modes)(connector); 311 } 312 313 if (count == 0 && connector->status == connector_status_connected) 314 count = drm_add_modes_noedid(connector, 1024, 768); 315 count += drm_helper_probe_add_cmdline_mode(connector); 316 if (count == 0) 317 goto prune; 318 319 drm_mode_connector_list_update(connector); 320 321 if (connector->interlace_allowed) 322 mode_flags |= DRM_MODE_FLAG_INTERLACE; 323 if (connector->doublescan_allowed) 324 mode_flags |= DRM_MODE_FLAG_DBLSCAN; 325 if (connector->stereo_allowed) 326 mode_flags |= DRM_MODE_FLAG_3D_MASK; 327 328 list_for_each_entry(mode, &connector->modes, head) { 329 if (mode->status == MODE_OK) 330 mode->status = drm_mode_validate_basic(mode); 331 332 if (mode->status == MODE_OK) 333 mode->status = drm_mode_validate_size(mode, maxX, maxY); 334 335 if (mode->status == MODE_OK) 336 mode->status = drm_mode_validate_flag(mode, mode_flags); 337 338 if (mode->status == MODE_OK && connector_funcs->mode_valid) 339 mode->status = connector_funcs->mode_valid(connector, 340 mode); 341 } 342 343 prune: 344 drm_mode_prune_invalid(dev, &connector->modes, verbose_prune); 345 346 if (list_empty(&connector->modes)) 347 return 0; 348 349 list_for_each_entry(mode, &connector->modes, head) 350 mode->vrefresh = drm_mode_vrefresh(mode); 351 352 drm_mode_sort(&connector->modes); 353 354 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector->base.id, 355 connector->name); 356 list_for_each_entry(mode, &connector->modes, head) { 357 drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V); 358 drm_mode_debug_printmodeline(mode); 359 } 360 361 return count; 362 } 363 EXPORT_SYMBOL(drm_helper_probe_single_connector_modes); 364 365 /** 366 * drm_kms_helper_hotplug_event - fire off KMS hotplug events 367 * @dev: drm_device whose connector state changed 368 * 369 * This function fires off the uevent for userspace and also calls the 370 * output_poll_changed function, which is most commonly used to inform the fbdev 371 * emulation code and allow it to update the fbcon output configuration. 372 * 373 * Drivers should call this from their hotplug handling code when a change is 374 * detected. Note that this function does not do any output detection of its 375 * own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the 376 * driver already. 377 * 378 * This function must be called from process context with no mode 379 * setting locks held. 380 */ 381 void drm_kms_helper_hotplug_event(struct drm_device *dev) 382 { 383 /* send a uevent + call fbdev */ 384 drm_sysfs_hotplug_event(dev); 385 if (dev->mode_config.funcs->output_poll_changed) 386 dev->mode_config.funcs->output_poll_changed(dev); 387 } 388 EXPORT_SYMBOL(drm_kms_helper_hotplug_event); 389 390 static void output_poll_execute(struct work_struct *work) 391 { 392 struct delayed_work *delayed_work = to_delayed_work(work); 393 struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work); 394 struct drm_connector *connector; 395 enum drm_connector_status old_status; 396 bool repoll = false, changed; 397 398 /* Pick up any changes detected by the probe functions. */ 399 changed = dev->mode_config.delayed_event; 400 dev->mode_config.delayed_event = false; 401 402 if (!drm_kms_helper_poll) 403 goto out; 404 405 if (!mutex_trylock(&dev->mode_config.mutex)) { 406 repoll = true; 407 goto out; 408 } 409 410 drm_for_each_connector(connector, dev) { 411 412 /* Ignore forced connectors. */ 413 if (connector->force) 414 continue; 415 416 /* Ignore HPD capable connectors and connectors where we don't 417 * want any hotplug detection at all for polling. */ 418 if (!connector->polled || connector->polled == DRM_CONNECTOR_POLL_HPD) 419 continue; 420 421 old_status = connector->status; 422 /* if we are connected and don't want to poll for disconnect 423 skip it */ 424 if (old_status == connector_status_connected && 425 !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT)) 426 continue; 427 428 repoll = true; 429 430 connector->status = drm_connector_detect(connector, false); 431 if (old_status != connector->status) { 432 const char *old, *new; 433 434 /* 435 * The poll work sets force=false when calling detect so 436 * that drivers can avoid to do disruptive tests (e.g. 437 * when load detect cycles could cause flickering on 438 * other, running displays). This bears the risk that we 439 * flip-flop between unknown here in the poll work and 440 * the real state when userspace forces a full detect 441 * call after receiving a hotplug event due to this 442 * change. 443 * 444 * Hence clamp an unknown detect status to the old 445 * value. 446 */ 447 if (connector->status == connector_status_unknown) { 448 connector->status = old_status; 449 continue; 450 } 451 452 old = drm_get_connector_status_name(old_status); 453 new = drm_get_connector_status_name(connector->status); 454 455 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] " 456 "status updated from %s to %s\n", 457 connector->base.id, 458 connector->name, 459 old, new); 460 461 changed = true; 462 } 463 } 464 465 mutex_unlock(&dev->mode_config.mutex); 466 467 out: 468 if (changed) 469 drm_kms_helper_hotplug_event(dev); 470 471 if (repoll) 472 schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD); 473 } 474 475 /** 476 * drm_kms_helper_poll_disable - disable output polling 477 * @dev: drm_device 478 * 479 * This function disables the output polling work. 480 * 481 * Drivers can call this helper from their device suspend implementation. It is 482 * not an error to call this even when output polling isn't enabled or arlready 483 * disabled. 484 */ 485 void drm_kms_helper_poll_disable(struct drm_device *dev) 486 { 487 if (!dev->mode_config.poll_enabled) 488 return; 489 cancel_delayed_work_sync(&dev->mode_config.output_poll_work); 490 } 491 EXPORT_SYMBOL(drm_kms_helper_poll_disable); 492 493 /** 494 * drm_kms_helper_poll_enable - re-enable output polling. 495 * @dev: drm_device 496 * 497 * This function re-enables the output polling work. 498 * 499 * Drivers can call this helper from their device resume implementation. It is 500 * an error to call this when the output polling support has not yet been set 501 * up. 502 */ 503 void drm_kms_helper_poll_enable(struct drm_device *dev) 504 { 505 mutex_lock(&dev->mode_config.mutex); 506 drm_kms_helper_poll_enable_locked(dev); 507 mutex_unlock(&dev->mode_config.mutex); 508 } 509 EXPORT_SYMBOL(drm_kms_helper_poll_enable); 510 511 /** 512 * drm_kms_helper_poll_init - initialize and enable output polling 513 * @dev: drm_device 514 * 515 * This function intializes and then also enables output polling support for 516 * @dev. Drivers which do not have reliable hotplug support in hardware can use 517 * this helper infrastructure to regularly poll such connectors for changes in 518 * their connection state. 519 * 520 * Drivers can control which connectors are polled by setting the 521 * DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On 522 * connectors where probing live outputs can result in visual distortion drivers 523 * should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this. 524 * Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are 525 * completely ignored by the polling logic. 526 * 527 * Note that a connector can be both polled and probed from the hotplug handler, 528 * in case the hotplug interrupt is known to be unreliable. 529 */ 530 void drm_kms_helper_poll_init(struct drm_device *dev) 531 { 532 INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute); 533 dev->mode_config.poll_enabled = true; 534 535 drm_kms_helper_poll_enable(dev); 536 } 537 EXPORT_SYMBOL(drm_kms_helper_poll_init); 538 539 /** 540 * drm_kms_helper_poll_fini - disable output polling and clean it up 541 * @dev: drm_device 542 */ 543 void drm_kms_helper_poll_fini(struct drm_device *dev) 544 { 545 drm_kms_helper_poll_disable(dev); 546 } 547 EXPORT_SYMBOL(drm_kms_helper_poll_fini); 548 549 /** 550 * drm_helper_hpd_irq_event - hotplug processing 551 * @dev: drm_device 552 * 553 * Drivers can use this helper function to run a detect cycle on all connectors 554 * which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All 555 * other connectors are ignored, which is useful to avoid reprobing fixed 556 * panels. 557 * 558 * This helper function is useful for drivers which can't or don't track hotplug 559 * interrupts for each connector. 560 * 561 * Drivers which support hotplug interrupts for each connector individually and 562 * which have a more fine-grained detect logic should bypass this code and 563 * directly call drm_kms_helper_hotplug_event() in case the connector state 564 * changed. 565 * 566 * This function must be called from process context with no mode 567 * setting locks held. 568 * 569 * Note that a connector can be both polled and probed from the hotplug handler, 570 * in case the hotplug interrupt is known to be unreliable. 571 */ 572 bool drm_helper_hpd_irq_event(struct drm_device *dev) 573 { 574 struct drm_connector *connector; 575 enum drm_connector_status old_status; 576 bool changed = false; 577 578 if (!dev->mode_config.poll_enabled) 579 return false; 580 581 mutex_lock(&dev->mode_config.mutex); 582 drm_for_each_connector(connector, dev) { 583 584 /* Only handle HPD capable connectors. */ 585 if (!(connector->polled & DRM_CONNECTOR_POLL_HPD)) 586 continue; 587 588 old_status = connector->status; 589 590 connector->status = drm_connector_detect(connector, false); 591 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n", 592 connector->base.id, 593 connector->name, 594 drm_get_connector_status_name(old_status), 595 drm_get_connector_status_name(connector->status)); 596 if (old_status != connector->status) 597 changed = true; 598 } 599 600 mutex_unlock(&dev->mode_config.mutex); 601 602 if (changed) 603 drm_kms_helper_hotplug_event(dev); 604 605 return changed; 606 } 607 EXPORT_SYMBOL(drm_helper_hpd_irq_event); 608