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 58 static bool drm_kms_helper_poll = true; 59 module_param_named(poll, drm_kms_helper_poll, bool, 0600); 60 61 static enum drm_mode_status 62 drm_mode_validate_flag(const struct drm_display_mode *mode, 63 int flags) 64 { 65 if ((mode->flags & DRM_MODE_FLAG_INTERLACE) && 66 !(flags & DRM_MODE_FLAG_INTERLACE)) 67 return MODE_NO_INTERLACE; 68 69 if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) && 70 !(flags & DRM_MODE_FLAG_DBLSCAN)) 71 return MODE_NO_DBLESCAN; 72 73 if ((mode->flags & DRM_MODE_FLAG_3D_MASK) && 74 !(flags & DRM_MODE_FLAG_3D_MASK)) 75 return MODE_NO_STEREO; 76 77 return MODE_OK; 78 } 79 80 static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector) 81 { 82 struct drm_display_mode *mode; 83 84 if (!connector->cmdline_mode.specified) 85 return 0; 86 87 mode = drm_mode_create_from_cmdline_mode(connector->dev, 88 &connector->cmdline_mode); 89 if (mode == NULL) 90 return 0; 91 92 drm_mode_probed_add(connector, mode); 93 return 1; 94 } 95 96 #define DRM_OUTPUT_POLL_PERIOD (10*HZ) 97 /** 98 * drm_kms_helper_poll_enable_locked - re-enable output polling. 99 * @dev: drm_device 100 * 101 * This function re-enables the output polling work without 102 * locking the mode_config mutex. 103 * 104 * This is like drm_kms_helper_poll_enable() however it is to be 105 * called from a context where the mode_config mutex is locked 106 * already. 107 */ 108 void drm_kms_helper_poll_enable_locked(struct drm_device *dev) 109 { 110 bool poll = false; 111 struct drm_connector *connector; 112 113 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex)); 114 115 if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll) 116 return; 117 118 drm_for_each_connector(connector, dev) { 119 if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT | 120 DRM_CONNECTOR_POLL_DISCONNECT)) 121 poll = true; 122 } 123 124 if (poll) 125 schedule_delayed_work(&dev->mode_config.output_poll_work, DRM_OUTPUT_POLL_PERIOD); 126 } 127 EXPORT_SYMBOL(drm_kms_helper_poll_enable_locked); 128 129 130 static int drm_helper_probe_single_connector_modes_merge_bits(struct drm_connector *connector, 131 uint32_t maxX, uint32_t maxY, bool merge_type_bits) 132 { 133 struct drm_device *dev = connector->dev; 134 struct drm_display_mode *mode; 135 const struct drm_connector_helper_funcs *connector_funcs = 136 connector->helper_private; 137 int count = 0; 138 int mode_flags = 0; 139 bool verbose_prune = true; 140 enum drm_connector_status old_status; 141 142 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex)); 143 144 DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id, 145 connector->name); 146 /* set all modes to the unverified state */ 147 list_for_each_entry(mode, &connector->modes, head) 148 mode->status = MODE_UNVERIFIED; 149 150 if (connector->force) { 151 if (connector->force == DRM_FORCE_ON || 152 connector->force == DRM_FORCE_ON_DIGITAL) 153 connector->status = connector_status_connected; 154 else 155 connector->status = connector_status_disconnected; 156 if (connector->funcs->force) 157 connector->funcs->force(connector); 158 } else { 159 old_status = connector->status; 160 161 connector->status = connector->funcs->detect(connector, true); 162 163 /* 164 * Normally either the driver's hpd code or the poll loop should 165 * pick up any changes and fire the hotplug event. But if 166 * userspace sneaks in a probe, we might miss a change. Hence 167 * check here, and if anything changed start the hotplug code. 168 */ 169 if (old_status != connector->status) { 170 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %d to %d\n", 171 connector->base.id, 172 connector->name, 173 old_status, connector->status); 174 175 /* 176 * The hotplug event code might call into the fb 177 * helpers, and so expects that we do not hold any 178 * locks. Fire up the poll struct instead, it will 179 * disable itself again. 180 */ 181 dev->mode_config.delayed_event = true; 182 if (dev->mode_config.poll_enabled) 183 schedule_delayed_work(&dev->mode_config.output_poll_work, 184 0); 185 } 186 } 187 188 /* Re-enable polling in case the global poll config changed. */ 189 if (drm_kms_helper_poll != dev->mode_config.poll_running) 190 drm_kms_helper_poll_enable_locked(dev); 191 192 dev->mode_config.poll_running = drm_kms_helper_poll; 193 194 if (connector->status == connector_status_disconnected) { 195 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n", 196 connector->base.id, connector->name); 197 drm_mode_connector_update_edid_property(connector, NULL); 198 verbose_prune = false; 199 goto prune; 200 } 201 202 #ifdef CONFIG_DRM_LOAD_EDID_FIRMWARE 203 count = drm_load_edid_firmware(connector); 204 if (count == 0) 205 #endif 206 { 207 if (connector->override_edid) { 208 struct edid *edid = (struct edid *) connector->edid_blob_ptr->data; 209 210 count = drm_add_edid_modes(connector, edid); 211 drm_edid_to_eld(connector, edid); 212 } else 213 count = (*connector_funcs->get_modes)(connector); 214 } 215 216 if (count == 0 && connector->status == connector_status_connected) 217 count = drm_add_modes_noedid(connector, 1024, 768); 218 count += drm_helper_probe_add_cmdline_mode(connector); 219 if (count == 0) 220 goto prune; 221 222 drm_mode_connector_list_update(connector, merge_type_bits); 223 224 if (connector->interlace_allowed) 225 mode_flags |= DRM_MODE_FLAG_INTERLACE; 226 if (connector->doublescan_allowed) 227 mode_flags |= DRM_MODE_FLAG_DBLSCAN; 228 if (connector->stereo_allowed) 229 mode_flags |= DRM_MODE_FLAG_3D_MASK; 230 231 list_for_each_entry(mode, &connector->modes, head) { 232 mode->status = drm_mode_validate_basic(mode); 233 234 if (mode->status == MODE_OK) 235 mode->status = drm_mode_validate_size(mode, maxX, maxY); 236 237 if (mode->status == MODE_OK) 238 mode->status = drm_mode_validate_flag(mode, mode_flags); 239 240 if (mode->status == MODE_OK && connector_funcs->mode_valid) 241 mode->status = connector_funcs->mode_valid(connector, 242 mode); 243 } 244 245 prune: 246 drm_mode_prune_invalid(dev, &connector->modes, verbose_prune); 247 248 if (list_empty(&connector->modes)) 249 return 0; 250 251 list_for_each_entry(mode, &connector->modes, head) 252 mode->vrefresh = drm_mode_vrefresh(mode); 253 254 drm_mode_sort(&connector->modes); 255 256 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector->base.id, 257 connector->name); 258 list_for_each_entry(mode, &connector->modes, head) { 259 drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V); 260 drm_mode_debug_printmodeline(mode); 261 } 262 263 return count; 264 } 265 266 /** 267 * drm_helper_probe_single_connector_modes - get complete set of display modes 268 * @connector: connector to probe 269 * @maxX: max width for modes 270 * @maxY: max height for modes 271 * 272 * Based on the helper callbacks implemented by @connector try to detect all 273 * valid modes. Modes will first be added to the connector's probed_modes list, 274 * then culled (based on validity and the @maxX, @maxY parameters) and put into 275 * the normal modes list. 276 * 277 * Intended to be use as a generic implementation of the ->fill_modes() 278 * @connector vfunc for drivers that use the crtc helpers for output mode 279 * filtering and detection. 280 * 281 * Returns: 282 * The number of modes found on @connector. 283 */ 284 int drm_helper_probe_single_connector_modes(struct drm_connector *connector, 285 uint32_t maxX, uint32_t maxY) 286 { 287 return drm_helper_probe_single_connector_modes_merge_bits(connector, maxX, maxY, true); 288 } 289 EXPORT_SYMBOL(drm_helper_probe_single_connector_modes); 290 291 /** 292 * drm_helper_probe_single_connector_modes_nomerge - get complete set of display modes 293 * @connector: connector to probe 294 * @maxX: max width for modes 295 * @maxY: max height for modes 296 * 297 * This operates like drm_hehlper_probe_single_connector_modes except it 298 * replaces the mode bits instead of merging them for preferred modes. 299 */ 300 int drm_helper_probe_single_connector_modes_nomerge(struct drm_connector *connector, 301 uint32_t maxX, uint32_t maxY) 302 { 303 return drm_helper_probe_single_connector_modes_merge_bits(connector, maxX, maxY, false); 304 } 305 EXPORT_SYMBOL(drm_helper_probe_single_connector_modes_nomerge); 306 307 /** 308 * drm_kms_helper_hotplug_event - fire off KMS hotplug events 309 * @dev: drm_device whose connector state changed 310 * 311 * This function fires off the uevent for userspace and also calls the 312 * output_poll_changed function, which is most commonly used to inform the fbdev 313 * emulation code and allow it to update the fbcon output configuration. 314 * 315 * Drivers should call this from their hotplug handling code when a change is 316 * detected. Note that this function does not do any output detection of its 317 * own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the 318 * driver already. 319 * 320 * This function must be called from process context with no mode 321 * setting locks held. 322 */ 323 void drm_kms_helper_hotplug_event(struct drm_device *dev) 324 { 325 /* send a uevent + call fbdev */ 326 drm_sysfs_hotplug_event(dev); 327 if (dev->mode_config.funcs->output_poll_changed) 328 dev->mode_config.funcs->output_poll_changed(dev); 329 } 330 EXPORT_SYMBOL(drm_kms_helper_hotplug_event); 331 332 static void output_poll_execute(struct work_struct *work) 333 { 334 struct delayed_work *delayed_work = to_delayed_work(work); 335 struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work); 336 struct drm_connector *connector; 337 enum drm_connector_status old_status; 338 bool repoll = false, changed; 339 340 /* Pick up any changes detected by the probe functions. */ 341 changed = dev->mode_config.delayed_event; 342 dev->mode_config.delayed_event = false; 343 344 if (!drm_kms_helper_poll) 345 goto out; 346 347 mutex_lock(&dev->mode_config.mutex); 348 drm_for_each_connector(connector, dev) { 349 350 /* Ignore forced connectors. */ 351 if (connector->force) 352 continue; 353 354 /* Ignore HPD capable connectors and connectors where we don't 355 * want any hotplug detection at all for polling. */ 356 if (!connector->polled || connector->polled == DRM_CONNECTOR_POLL_HPD) 357 continue; 358 359 old_status = connector->status; 360 /* if we are connected and don't want to poll for disconnect 361 skip it */ 362 if (old_status == connector_status_connected && 363 !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT)) 364 continue; 365 366 repoll = true; 367 368 connector->status = connector->funcs->detect(connector, false); 369 if (old_status != connector->status) { 370 const char *old, *new; 371 372 /* 373 * The poll work sets force=false when calling detect so 374 * that drivers can avoid to do disruptive tests (e.g. 375 * when load detect cycles could cause flickering on 376 * other, running displays). This bears the risk that we 377 * flip-flop between unknown here in the poll work and 378 * the real state when userspace forces a full detect 379 * call after receiving a hotplug event due to this 380 * change. 381 * 382 * Hence clamp an unknown detect status to the old 383 * value. 384 */ 385 if (connector->status == connector_status_unknown) { 386 connector->status = old_status; 387 continue; 388 } 389 390 old = drm_get_connector_status_name(old_status); 391 new = drm_get_connector_status_name(connector->status); 392 393 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] " 394 "status updated from %s to %s\n", 395 connector->base.id, 396 connector->name, 397 old, new); 398 399 changed = true; 400 } 401 } 402 403 mutex_unlock(&dev->mode_config.mutex); 404 405 out: 406 if (changed) 407 drm_kms_helper_hotplug_event(dev); 408 409 if (repoll) 410 schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD); 411 } 412 413 /** 414 * drm_kms_helper_poll_disable - disable output polling 415 * @dev: drm_device 416 * 417 * This function disables the output polling work. 418 * 419 * Drivers can call this helper from their device suspend implementation. It is 420 * not an error to call this even when output polling isn't enabled or arlready 421 * disabled. 422 */ 423 void drm_kms_helper_poll_disable(struct drm_device *dev) 424 { 425 if (!dev->mode_config.poll_enabled) 426 return; 427 cancel_delayed_work_sync(&dev->mode_config.output_poll_work); 428 } 429 EXPORT_SYMBOL(drm_kms_helper_poll_disable); 430 431 /** 432 * drm_kms_helper_poll_enable - re-enable output polling. 433 * @dev: drm_device 434 * 435 * This function re-enables the output polling work. 436 * 437 * Drivers can call this helper from their device resume implementation. It is 438 * an error to call this when the output polling support has not yet been set 439 * up. 440 */ 441 void drm_kms_helper_poll_enable(struct drm_device *dev) 442 { 443 mutex_lock(&dev->mode_config.mutex); 444 drm_kms_helper_poll_enable_locked(dev); 445 mutex_unlock(&dev->mode_config.mutex); 446 } 447 EXPORT_SYMBOL(drm_kms_helper_poll_enable); 448 449 /** 450 * drm_kms_helper_poll_init - initialize and enable output polling 451 * @dev: drm_device 452 * 453 * This function intializes and then also enables output polling support for 454 * @dev. Drivers which do not have reliable hotplug support in hardware can use 455 * this helper infrastructure to regularly poll such connectors for changes in 456 * their connection state. 457 * 458 * Drivers can control which connectors are polled by setting the 459 * DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On 460 * connectors where probing live outputs can result in visual distortion drivers 461 * should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this. 462 * Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are 463 * completely ignored by the polling logic. 464 * 465 * Note that a connector can be both polled and probed from the hotplug handler, 466 * in case the hotplug interrupt is known to be unreliable. 467 */ 468 void drm_kms_helper_poll_init(struct drm_device *dev) 469 { 470 INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute); 471 dev->mode_config.poll_enabled = true; 472 473 drm_kms_helper_poll_enable(dev); 474 } 475 EXPORT_SYMBOL(drm_kms_helper_poll_init); 476 477 /** 478 * drm_kms_helper_poll_fini - disable output polling and clean it up 479 * @dev: drm_device 480 */ 481 void drm_kms_helper_poll_fini(struct drm_device *dev) 482 { 483 drm_kms_helper_poll_disable(dev); 484 } 485 EXPORT_SYMBOL(drm_kms_helper_poll_fini); 486 487 /** 488 * drm_helper_hpd_irq_event - hotplug processing 489 * @dev: drm_device 490 * 491 * Drivers can use this helper function to run a detect cycle on all connectors 492 * which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All 493 * other connectors are ignored, which is useful to avoid reprobing fixed 494 * panels. 495 * 496 * This helper function is useful for drivers which can't or don't track hotplug 497 * interrupts for each connector. 498 * 499 * Drivers which support hotplug interrupts for each connector individually and 500 * which have a more fine-grained detect logic should bypass this code and 501 * directly call drm_kms_helper_hotplug_event() in case the connector state 502 * changed. 503 * 504 * This function must be called from process context with no mode 505 * setting locks held. 506 * 507 * Note that a connector can be both polled and probed from the hotplug handler, 508 * in case the hotplug interrupt is known to be unreliable. 509 */ 510 bool drm_helper_hpd_irq_event(struct drm_device *dev) 511 { 512 struct drm_connector *connector; 513 enum drm_connector_status old_status; 514 bool changed = false; 515 516 if (!dev->mode_config.poll_enabled) 517 return false; 518 519 mutex_lock(&dev->mode_config.mutex); 520 drm_for_each_connector(connector, dev) { 521 522 /* Only handle HPD capable connectors. */ 523 if (!(connector->polled & DRM_CONNECTOR_POLL_HPD)) 524 continue; 525 526 old_status = connector->status; 527 528 connector->status = connector->funcs->detect(connector, false); 529 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n", 530 connector->base.id, 531 connector->name, 532 drm_get_connector_status_name(old_status), 533 drm_get_connector_status_name(connector->status)); 534 if (old_status != connector->status) 535 changed = true; 536 } 537 538 mutex_unlock(&dev->mode_config.mutex); 539 540 if (changed) 541 drm_kms_helper_hotplug_event(dev); 542 543 return changed; 544 } 545 EXPORT_SYMBOL(drm_helper_hpd_irq_event); 546