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/drm_bridge.h>
  36#include <drm/drm_client_event.h>
  37#include <drm/drm_crtc.h>
  38#include <drm/drm_edid.h>
  39#include <drm/drm_fourcc.h>
  40#include <drm/drm_managed.h>
  41#include <drm/drm_modeset_helper_vtables.h>
  42#include <drm/drm_print.h>
  43#include <drm/drm_probe_helper.h>
  44#include <drm/drm_sysfs.h>
  45
  46#include "drm_crtc_helper_internal.h"
  47
  48/**
  49 * DOC: output probing helper overview
  50 *
  51 * This library provides some helper code for output probing. It provides an
  52 * implementation of the core &drm_connector_funcs.fill_modes interface with
  53 * drm_helper_probe_single_connector_modes().
  54 *
  55 * It also provides support for polling connectors with a work item and for
  56 * generic hotplug interrupt handling where the driver doesn't or cannot keep
  57 * track of a per-connector hpd interrupt.
  58 *
  59 * This helper library can be used independently of the modeset helper library.
  60 * Drivers can also overwrite different parts e.g. use their own hotplug
  61 * handling code to avoid probing unrelated outputs.
  62 *
  63 * The probe helpers share the function table structures with other display
  64 * helper libraries. See &struct drm_connector_helper_funcs for the details.
  65 */
  66
  67static bool drm_kms_helper_poll = true;
  68module_param_named(poll, drm_kms_helper_poll, bool, 0600);
  69
  70static enum drm_mode_status
  71drm_mode_validate_flag(const struct drm_display_mode *mode,
  72		       int flags)
  73{
  74	if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&
  75	    !(flags & DRM_MODE_FLAG_INTERLACE))
  76		return MODE_NO_INTERLACE;
  77
  78	if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&
  79	    !(flags & DRM_MODE_FLAG_DBLSCAN))
  80		return MODE_NO_DBLESCAN;
  81
  82	if ((mode->flags & DRM_MODE_FLAG_3D_MASK) &&
  83	    !(flags & DRM_MODE_FLAG_3D_MASK))
  84		return MODE_NO_STEREO;
  85
  86	return MODE_OK;
  87}
  88
  89static int
  90drm_mode_validate_pipeline(struct drm_display_mode *mode,
  91			   struct drm_connector *connector,
  92			   struct drm_modeset_acquire_ctx *ctx,
  93			   enum drm_mode_status *status)
  94{
  95	struct drm_device *dev = connector->dev;
  96	struct drm_encoder *encoder;
  97	int ret;
  98
  99	/* Step 1: Validate against connector */
 100	ret = drm_connector_mode_valid(connector, mode, ctx, status);
 101	if (ret || *status != MODE_OK)
 102		return ret;
 103
 104	/* Step 2: Validate against encoders and crtcs */
 105	drm_connector_for_each_possible_encoder(connector, encoder) {
 106		struct drm_bridge *bridge;
 107		struct drm_crtc *crtc;
 108
 109		*status = drm_encoder_mode_valid(encoder, mode);
 110		if (*status != MODE_OK) {
 111			/* No point in continuing for crtc check as this encoder
 112			 * will not accept the mode anyway. If all encoders
 113			 * reject the mode then, at exit, ret will not be
 114			 * MODE_OK. */
 115			continue;
 116		}
 117
 118		bridge = drm_bridge_chain_get_first_bridge(encoder);
 119		*status = drm_bridge_chain_mode_valid(bridge,
 120						      &connector->display_info,
 121						      mode);
 122		if (*status != MODE_OK) {
 123			/* There is also no point in continuing for crtc check
 124			 * here. */
 125			continue;
 126		}
 127
 128		drm_for_each_crtc(crtc, dev) {
 129			if (!drm_encoder_crtc_ok(encoder, crtc))
 130				continue;
 131
 132			*status = drm_crtc_mode_valid(crtc, mode);
 133			if (*status == MODE_OK) {
 134				/* If we get to this point there is at least
 135				 * one combination of encoder+crtc that works
 136				 * for this mode. Lets return now. */
 137				return 0;
 138			}
 139		}
 140	}
 141
 142	return 0;
 143}
 144
 145static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector)
 146{
 147	struct drm_cmdline_mode *cmdline_mode;
 148	struct drm_display_mode *mode;
 149
 150	cmdline_mode = &connector->cmdline_mode;
 151	if (!cmdline_mode->specified)
 152		return 0;
 153
 154	/* Only add a GTF mode if we find no matching probed modes */
 155	list_for_each_entry(mode, &connector->probed_modes, head) {
 156		if (mode->hdisplay != cmdline_mode->xres ||
 157		    mode->vdisplay != cmdline_mode->yres)
 158			continue;
 159
 160		if (cmdline_mode->refresh_specified) {
 161			/* The probed mode's vrefresh is set until later */
 162			if (drm_mode_vrefresh(mode) != cmdline_mode->refresh)
 163				continue;
 164		}
 165
 166		/* Mark the matching mode as being preferred by the user */
 167		mode->type |= DRM_MODE_TYPE_USERDEF;
 168		return 0;
 169	}
 170
 171	mode = drm_mode_create_from_cmdline_mode(connector->dev,
 172						 cmdline_mode);
 173	if (mode == NULL)
 174		return 0;
 175
 176	drm_mode_probed_add(connector, mode);
 177	return 1;
 178}
 179
 180enum drm_mode_status drm_crtc_mode_valid(struct drm_crtc *crtc,
 181					 const struct drm_display_mode *mode)
 182{
 183	const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 184
 185	if (!crtc_funcs || !crtc_funcs->mode_valid)
 186		return MODE_OK;
 187
 188	return crtc_funcs->mode_valid(crtc, mode);
 189}
 190
 191enum drm_mode_status drm_encoder_mode_valid(struct drm_encoder *encoder,
 192					    const struct drm_display_mode *mode)
 193{
 194	const struct drm_encoder_helper_funcs *encoder_funcs =
 195		encoder->helper_private;
 196
 197	if (!encoder_funcs || !encoder_funcs->mode_valid)
 198		return MODE_OK;
 199
 200	return encoder_funcs->mode_valid(encoder, mode);
 201}
 202
 203int
 204drm_connector_mode_valid(struct drm_connector *connector,
 205			 struct drm_display_mode *mode,
 206			 struct drm_modeset_acquire_ctx *ctx,
 207			 enum drm_mode_status *status)
 208{
 209	const struct drm_connector_helper_funcs *connector_funcs =
 210		connector->helper_private;
 211	int ret = 0;
 212
 213	if (!connector_funcs)
 214		*status = MODE_OK;
 215	else if (connector_funcs->mode_valid_ctx)
 216		ret = connector_funcs->mode_valid_ctx(connector, mode, ctx,
 217						      status);
 218	else if (connector_funcs->mode_valid)
 219		*status = connector_funcs->mode_valid(connector, mode);
 220	else
 221		*status = MODE_OK;
 222
 223	return ret;
 224}
 225
 226static void drm_kms_helper_disable_hpd(struct drm_device *dev)
 227{
 228	struct drm_connector *connector;
 229	struct drm_connector_list_iter conn_iter;
 230
 231	drm_connector_list_iter_begin(dev, &conn_iter);
 232	drm_for_each_connector_iter(connector, &conn_iter) {
 233		const struct drm_connector_helper_funcs *funcs =
 234			connector->helper_private;
 235
 236		if (funcs && funcs->disable_hpd)
 237			funcs->disable_hpd(connector);
 238	}
 239	drm_connector_list_iter_end(&conn_iter);
 240}
 241
 242static bool drm_kms_helper_enable_hpd(struct drm_device *dev)
 243{
 244	bool poll = false;
 245	struct drm_connector *connector;
 246	struct drm_connector_list_iter conn_iter;
 247
 248	drm_connector_list_iter_begin(dev, &conn_iter);
 249	drm_for_each_connector_iter(connector, &conn_iter) {
 250		const struct drm_connector_helper_funcs *funcs =
 251			connector->helper_private;
 252
 253		if (funcs && funcs->enable_hpd)
 254			funcs->enable_hpd(connector);
 255
 256		if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |
 257					 DRM_CONNECTOR_POLL_DISCONNECT))
 258			poll = true;
 259	}
 260	drm_connector_list_iter_end(&conn_iter);
 261
 262	return poll;
 263}
 264
 265#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
 266static void reschedule_output_poll_work(struct drm_device *dev)
 267{
 268	unsigned long delay = DRM_OUTPUT_POLL_PERIOD;
 269
 270	if (dev->mode_config.delayed_event)
 271		/*
 272		 * FIXME:
 273		 *
 274		 * Use short (1s) delay to handle the initial delayed event.
 275		 * This delay should not be needed, but Optimus/nouveau will
 276		 * fail in a mysterious way if the delayed event is handled as
 277		 * soon as possible like it is done in
 278		 * drm_helper_probe_single_connector_modes() in case the poll
 279		 * was enabled before.
 280		 */
 281		delay = HZ;
 282
 283	schedule_delayed_work(&dev->mode_config.output_poll_work, delay);
 284}
 285
 286/**
 287 * drm_kms_helper_poll_enable - re-enable output polling.
 288 * @dev: drm_device
 289 *
 290 * This function re-enables the output polling work, after it has been
 291 * temporarily disabled using drm_kms_helper_poll_disable(), for example over
 292 * suspend/resume.
 293 *
 294 * Drivers can call this helper from their device resume implementation. It is
 295 * not an error to call this even when output polling isn't enabled.
 296 *
 297 * If device polling was never initialized before, this call will trigger a
 298 * warning and return.
 299 *
 300 * Note that calls to enable and disable polling must be strictly ordered, which
 301 * is automatically the case when they're only call from suspend/resume
 302 * callbacks.
 303 */
 304void drm_kms_helper_poll_enable(struct drm_device *dev)
 305{
 306	if (drm_WARN_ON_ONCE(dev, !dev->mode_config.poll_enabled) ||
 307	    !drm_kms_helper_poll || dev->mode_config.poll_running)
 308		return;
 309
 310	if (drm_kms_helper_enable_hpd(dev) ||
 311	    dev->mode_config.delayed_event)
 312		reschedule_output_poll_work(dev);
 313
 314	dev->mode_config.poll_running = true;
 315}
 316EXPORT_SYMBOL(drm_kms_helper_poll_enable);
 317
 318/**
 319 * drm_kms_helper_poll_reschedule - reschedule the output polling work
 320 * @dev: drm_device
 321 *
 322 * This function reschedules the output polling work, after polling for a
 323 * connector has been enabled.
 324 *
 325 * Drivers must call this helper after enabling polling for a connector by
 326 * setting %DRM_CONNECTOR_POLL_CONNECT / %DRM_CONNECTOR_POLL_DISCONNECT flags
 327 * in drm_connector::polled. Note that after disabling polling by clearing these
 328 * flags for a connector will stop the output polling work automatically if
 329 * the polling is disabled for all other connectors as well.
 330 *
 331 * The function can be called only after polling has been enabled by calling
 332 * drm_kms_helper_poll_init() / drm_kms_helper_poll_enable().
 333 */
 334void drm_kms_helper_poll_reschedule(struct drm_device *dev)
 335{
 336	if (dev->mode_config.poll_running)
 337		reschedule_output_poll_work(dev);
 338}
 339EXPORT_SYMBOL(drm_kms_helper_poll_reschedule);
 340
 341static enum drm_connector_status
 342drm_helper_probe_detect_ctx(struct drm_connector *connector, bool force)
 343{
 344	const struct drm_connector_helper_funcs *funcs = connector->helper_private;
 345	struct drm_modeset_acquire_ctx ctx;
 346	int ret;
 347
 348	drm_modeset_acquire_init(&ctx, 0);
 349
 350retry:
 351	ret = drm_modeset_lock(&connector->dev->mode_config.connection_mutex, &ctx);
 352	if (!ret) {
 353		if (funcs->detect_ctx)
 354			ret = funcs->detect_ctx(connector, &ctx, force);
 355		else if (connector->funcs->detect)
 356			ret = connector->funcs->detect(connector, force);
 357		else
 358			ret = connector_status_connected;
 359	}
 360
 361	if (ret == -EDEADLK) {
 362		drm_modeset_backoff(&ctx);
 363		goto retry;
 364	}
 365
 366	if (WARN_ON(ret < 0))
 367		ret = connector_status_unknown;
 368
 369	if (ret != connector->status)
 370		connector->epoch_counter += 1;
 371
 372	drm_modeset_drop_locks(&ctx);
 373	drm_modeset_acquire_fini(&ctx);
 374
 375	return ret;
 376}
 377
 378/**
 379 * drm_helper_probe_detect - probe connector status
 380 * @connector: connector to probe
 381 * @ctx: acquire_ctx, or NULL to let this function handle locking.
 382 * @force: Whether destructive probe operations should be performed.
 383 *
 384 * This function calls the detect callbacks of the connector.
 385 * This function returns &drm_connector_status, or
 386 * if @ctx is set, it might also return -EDEADLK.
 387 */
 388int
 389drm_helper_probe_detect(struct drm_connector *connector,
 390			struct drm_modeset_acquire_ctx *ctx,
 391			bool force)
 392{
 393	const struct drm_connector_helper_funcs *funcs = connector->helper_private;
 394	struct drm_device *dev = connector->dev;
 395	int ret;
 396
 397	if (!ctx)
 398		return drm_helper_probe_detect_ctx(connector, force);
 399
 400	ret = drm_modeset_lock(&dev->mode_config.connection_mutex, ctx);
 401	if (ret)
 402		return ret;
 403
 404	if (funcs->detect_ctx)
 405		ret = funcs->detect_ctx(connector, ctx, force);
 406	else if (connector->funcs->detect)
 407		ret = connector->funcs->detect(connector, force);
 408	else
 409		ret = connector_status_connected;
 410
 411	if (ret != connector->status)
 412		connector->epoch_counter += 1;
 413
 414	return ret;
 415}
 416EXPORT_SYMBOL(drm_helper_probe_detect);
 417
 418static int drm_helper_probe_get_modes(struct drm_connector *connector)
 419{
 420	const struct drm_connector_helper_funcs *connector_funcs =
 421		connector->helper_private;
 422	int count;
 423
 424	count = connector_funcs->get_modes(connector);
 425
 426	/* The .get_modes() callback should not return negative values. */
 427	if (count < 0) {
 428		drm_err(connector->dev, ".get_modes() returned %pe\n",
 429			ERR_PTR(count));
 430		count = 0;
 431	}
 432
 433	/*
 434	 * Fallback for when DDC probe failed in drm_get_edid() and thus skipped
 435	 * override/firmware EDID.
 436	 */
 437	if (count == 0 && connector->status == connector_status_connected)
 438		count = drm_edid_override_connector_update(connector);
 439
 440	return count;
 441}
 442
 443static int __drm_helper_update_and_validate(struct drm_connector *connector,
 444					    uint32_t maxX, uint32_t maxY,
 445					    struct drm_modeset_acquire_ctx *ctx)
 446{
 447	struct drm_device *dev = connector->dev;
 448	struct drm_display_mode *mode;
 449	int mode_flags = 0;
 450	int ret;
 451
 452	drm_connector_list_update(connector);
 453
 454	if (connector->interlace_allowed)
 455		mode_flags |= DRM_MODE_FLAG_INTERLACE;
 456	if (connector->doublescan_allowed)
 457		mode_flags |= DRM_MODE_FLAG_DBLSCAN;
 458	if (connector->stereo_allowed)
 459		mode_flags |= DRM_MODE_FLAG_3D_MASK;
 460
 461	list_for_each_entry(mode, &connector->modes, head) {
 462		if (mode->status != MODE_OK)
 463			continue;
 464
 465		mode->status = drm_mode_validate_driver(dev, mode);
 466		if (mode->status != MODE_OK)
 467			continue;
 468
 469		mode->status = drm_mode_validate_size(mode, maxX, maxY);
 470		if (mode->status != MODE_OK)
 471			continue;
 472
 473		mode->status = drm_mode_validate_flag(mode, mode_flags);
 474		if (mode->status != MODE_OK)
 475			continue;
 476
 477		mode->status = drm_mode_validate_ycbcr420(mode, connector);
 478		if (mode->status != MODE_OK)
 479			continue;
 480
 481		ret = drm_mode_validate_pipeline(mode, connector, ctx,
 482						 &mode->status);
 483		if (ret) {
 484			drm_dbg_kms(dev,
 485				    "drm_mode_validate_pipeline failed: %d\n",
 486				    ret);
 487
 488			if (drm_WARN_ON_ONCE(dev, ret != -EDEADLK))
 489				mode->status = MODE_ERROR;
 490			else
 491				return -EDEADLK;
 492		}
 
 
 
 
 493	}
 494
 495	return 0;
 496}
 497
 498/**
 499 * drm_helper_probe_single_connector_modes - get complete set of display modes
 500 * @connector: connector to probe
 501 * @maxX: max width for modes
 502 * @maxY: max height for modes
 503 *
 504 * Based on the helper callbacks implemented by @connector in struct
 505 * &drm_connector_helper_funcs try to detect all valid modes.  Modes will first
 506 * be added to the connector's probed_modes list, then culled (based on validity
 507 * and the @maxX, @maxY parameters) and put into the normal modes list.
 508 *
 509 * Intended to be used as a generic implementation of the
 510 * &drm_connector_funcs.fill_modes() vfunc for drivers that use the CRTC helpers
 511 * for output mode filtering and detection.
 512 *
 513 * The basic procedure is as follows
 514 *
 515 * 1. All modes currently on the connector's modes list are marked as stale
 516 *
 517 * 2. New modes are added to the connector's probed_modes list with
 518 *    drm_mode_probed_add(). New modes start their life with status as OK.
 519 *    Modes are added from a single source using the following priority order.
 520 *
 521 *    - &drm_connector_helper_funcs.get_modes vfunc
 522 *    - if the connector status is connector_status_connected, standard
 523 *      VESA DMT modes up to 1024x768 are automatically added
 524 *      (drm_add_modes_noedid())
 525 *
 526 *    Finally modes specified via the kernel command line (video=...) are
 527 *    added in addition to what the earlier probes produced
 528 *    (drm_helper_probe_add_cmdline_mode()). These modes are generated
 529 *    using the VESA GTF/CVT formulas.
 530 *
 531 * 3. Modes are moved from the probed_modes list to the modes list. Potential
 532 *    duplicates are merged together (see drm_connector_list_update()).
 533 *    After this step the probed_modes list will be empty again.
 534 *
 535 * 4. Any non-stale mode on the modes list then undergoes validation
 536 *
 537 *    - drm_mode_validate_basic() performs basic sanity checks
 538 *    - drm_mode_validate_size() filters out modes larger than @maxX and @maxY
 539 *      (if specified)
 540 *    - drm_mode_validate_flag() checks the modes against basic connector
 541 *      capabilities (interlace_allowed,doublescan_allowed,stereo_allowed)
 542 *    - the optional &drm_connector_helper_funcs.mode_valid or
 543 *      &drm_connector_helper_funcs.mode_valid_ctx helpers can perform driver
 544 *      and/or sink specific checks
 545 *    - the optional &drm_crtc_helper_funcs.mode_valid,
 546 *      &drm_bridge_funcs.mode_valid and &drm_encoder_helper_funcs.mode_valid
 547 *      helpers can perform driver and/or source specific checks which are also
 548 *      enforced by the modeset/atomic helpers
 549 *
 550 * 5. Any mode whose status is not OK is pruned from the connector's modes list,
 551 *    accompanied by a debug message indicating the reason for the mode's
 552 *    rejection (see drm_mode_prune_invalid()).
 553 *
 554 * Returns:
 555 * The number of modes found on @connector.
 556 */
 557int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
 558					    uint32_t maxX, uint32_t maxY)
 559{
 560	struct drm_device *dev = connector->dev;
 561	struct drm_display_mode *mode;
 562	int count = 0, ret;
 563	enum drm_connector_status old_status;
 564	struct drm_modeset_acquire_ctx ctx;
 565
 566	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 567
 568	drm_modeset_acquire_init(&ctx, 0);
 569
 570	drm_dbg_kms(dev, "[CONNECTOR:%d:%s]\n", connector->base.id,
 571		    connector->name);
 572
 573retry:
 574	ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx);
 575	if (ret == -EDEADLK) {
 576		drm_modeset_backoff(&ctx);
 577		goto retry;
 578	} else
 579		WARN_ON(ret < 0);
 580
 581	/* set all old modes to the stale state */
 582	list_for_each_entry(mode, &connector->modes, head)
 583		mode->status = MODE_STALE;
 584
 585	old_status = connector->status;
 586
 587	if (connector->force) {
 588		if (connector->force == DRM_FORCE_ON ||
 589		    connector->force == DRM_FORCE_ON_DIGITAL)
 590			connector->status = connector_status_connected;
 591		else
 592			connector->status = connector_status_disconnected;
 593		if (connector->funcs->force)
 594			connector->funcs->force(connector);
 595	} else {
 596		ret = drm_helper_probe_detect(connector, &ctx, true);
 597
 598		if (ret == -EDEADLK) {
 599			drm_modeset_backoff(&ctx);
 600			goto retry;
 601		} else if (WARN(ret < 0, "Invalid return value %i for connector detection\n", ret))
 602			ret = connector_status_unknown;
 603
 604		connector->status = ret;
 605	}
 606
 607	/*
 608	 * Normally either the driver's hpd code or the poll loop should
 609	 * pick up any changes and fire the hotplug event. But if
 610	 * userspace sneaks in a probe, we might miss a change. Hence
 611	 * check here, and if anything changed start the hotplug code.
 612	 */
 613	if (old_status != connector->status) {
 614		drm_dbg_kms(dev, "[CONNECTOR:%d:%s] status updated from %s to %s\n",
 615			    connector->base.id, connector->name,
 616			    drm_get_connector_status_name(old_status),
 617			    drm_get_connector_status_name(connector->status));
 
 618
 619		/*
 620		 * The hotplug event code might call into the fb
 621		 * helpers, and so expects that we do not hold any
 622		 * locks. Fire up the poll struct instead, it will
 623		 * disable itself again.
 624		 */
 625		dev->mode_config.delayed_event = true;
 626		if (dev->mode_config.poll_enabled)
 627			mod_delayed_work(system_wq,
 628					 &dev->mode_config.output_poll_work,
 629					 0);
 630	}
 631
 632	/*
 633	 * Re-enable polling in case the global poll config changed but polling
 634	 * is still initialized.
 635	 */
 636	if (dev->mode_config.poll_enabled)
 637		drm_kms_helper_poll_enable(dev);
 638
 639	if (connector->status == connector_status_disconnected) {
 640		drm_dbg_kms(dev, "[CONNECTOR:%d:%s] disconnected\n",
 641			    connector->base.id, connector->name);
 642		drm_connector_update_edid_property(connector, NULL);
 643		drm_mode_prune_invalid(dev, &connector->modes, false);
 644		goto exit;
 645	}
 646
 647	count = drm_helper_probe_get_modes(connector);
 648
 649	if (count == 0 && (connector->status == connector_status_connected ||
 650			   connector->status == connector_status_unknown)) {
 651		count = drm_add_modes_noedid(connector, 1024, 768);
 652
 653		/*
 654		 * Section 4.2.2.6 (EDID Corruption Detection) of the DP 1.4a
 655		 * Link CTS specifies that 640x480 (the official "failsafe"
 656		 * mode) needs to be the default if there's no EDID.
 657		 */
 658		if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort)
 659			drm_set_preferred_mode(connector, 640, 480);
 660	}
 661	count += drm_helper_probe_add_cmdline_mode(connector);
 662	if (count != 0) {
 663		ret = __drm_helper_update_and_validate(connector, maxX, maxY, &ctx);
 664		if (ret == -EDEADLK) {
 665			drm_modeset_backoff(&ctx);
 666			goto retry;
 667		}
 668	}
 669
 670	drm_mode_prune_invalid(dev, &connector->modes, true);
 671
 672	/*
 673	 * Displayport spec section 5.2.1.2 ("Video Timing Format") says that
 674	 * all detachable sinks shall support 640x480 @60Hz as a fail safe
 675	 * mode. If all modes were pruned, perhaps because they need more
 676	 * lanes or a higher pixel clock than available, at least try to add
 677	 * in 640x480.
 678	 */
 679	if (list_empty(&connector->modes) &&
 680	    connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort) {
 681		count = drm_add_modes_noedid(connector, 640, 480);
 682		ret = __drm_helper_update_and_validate(connector, maxX, maxY, &ctx);
 683		if (ret == -EDEADLK) {
 684			drm_modeset_backoff(&ctx);
 685			goto retry;
 686		}
 687		drm_mode_prune_invalid(dev, &connector->modes, true);
 688	}
 689
 690exit:
 691	drm_modeset_drop_locks(&ctx);
 692	drm_modeset_acquire_fini(&ctx);
 693
 694	if (list_empty(&connector->modes))
 695		return 0;
 696
 697	drm_mode_sort(&connector->modes);
 698
 699	drm_dbg_kms(dev, "[CONNECTOR:%d:%s] probed modes:\n",
 700		    connector->base.id, connector->name);
 701
 702	list_for_each_entry(mode, &connector->modes, head) {
 703		drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
 704		drm_dbg_kms(dev, "Probed mode: " DRM_MODE_FMT "\n",
 705			    DRM_MODE_ARG(mode));
 706	}
 707
 708	return count;
 709}
 710EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
 711
 712/**
 713 * drm_kms_helper_hotplug_event - fire off KMS hotplug events
 714 * @dev: drm_device whose connector state changed
 715 *
 716 * This function fires off the uevent for userspace and also calls the
 717 * client hotplug function, which is most commonly used to inform the fbdev
 718 * emulation code and allow it to update the fbcon output configuration.
 719 *
 720 * Drivers should call this from their hotplug handling code when a change is
 721 * detected. Note that this function does not do any output detection of its
 722 * own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the
 723 * driver already.
 724 *
 725 * This function must be called from process context with no mode
 726 * setting locks held.
 727 *
 728 * If only a single connector has changed, consider calling
 729 * drm_kms_helper_connector_hotplug_event() instead.
 730 */
 731void drm_kms_helper_hotplug_event(struct drm_device *dev)
 732{
 
 733	drm_sysfs_hotplug_event(dev);
 
 
 
 734	drm_client_dev_hotplug(dev);
 735}
 736EXPORT_SYMBOL(drm_kms_helper_hotplug_event);
 737
 738/**
 739 * drm_kms_helper_connector_hotplug_event - fire off a KMS connector hotplug event
 740 * @connector: drm_connector which has changed
 741 *
 742 * This is the same as drm_kms_helper_hotplug_event(), except it fires a more
 743 * fine-grained uevent for a single connector.
 744 */
 745void drm_kms_helper_connector_hotplug_event(struct drm_connector *connector)
 746{
 747	struct drm_device *dev = connector->dev;
 748
 
 749	drm_sysfs_connector_hotplug_event(connector);
 
 
 
 750	drm_client_dev_hotplug(dev);
 751}
 752EXPORT_SYMBOL(drm_kms_helper_connector_hotplug_event);
 753
 754static void output_poll_execute(struct work_struct *work)
 755{
 756	struct delayed_work *delayed_work = to_delayed_work(work);
 757	struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);
 758	struct drm_connector *connector;
 759	struct drm_connector_list_iter conn_iter;
 760	enum drm_connector_status old_status;
 761	bool repoll = false, changed;
 762	u64 old_epoch_counter;
 763
 764	if (!dev->mode_config.poll_enabled)
 765		return;
 766
 767	/* Pick up any changes detected by the probe functions. */
 768	changed = dev->mode_config.delayed_event;
 769	dev->mode_config.delayed_event = false;
 770
 771	if (!drm_kms_helper_poll) {
 772		if (dev->mode_config.poll_running) {
 773			drm_kms_helper_disable_hpd(dev);
 774			dev->mode_config.poll_running = false;
 775		}
 776		goto out;
 777	}
 778
 779	if (!mutex_trylock(&dev->mode_config.mutex)) {
 780		repoll = true;
 781		goto out;
 782	}
 783
 784	drm_connector_list_iter_begin(dev, &conn_iter);
 785	drm_for_each_connector_iter(connector, &conn_iter) {
 786		/* Ignore forced connectors. */
 787		if (connector->force)
 788			continue;
 789
 790		/* Ignore HPD capable connectors and connectors where we don't
 791		 * want any hotplug detection at all for polling. */
 792		if (!connector->polled || connector->polled == DRM_CONNECTOR_POLL_HPD)
 793			continue;
 794
 795		old_status = connector->status;
 796		/* if we are connected and don't want to poll for disconnect
 797		   skip it */
 798		if (old_status == connector_status_connected &&
 799		    !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT))
 800			continue;
 801
 802		repoll = true;
 803
 804		old_epoch_counter = connector->epoch_counter;
 805		connector->status = drm_helper_probe_detect(connector, NULL, false);
 806		if (old_epoch_counter != connector->epoch_counter) {
 807			const char *old, *new;
 808
 809			/*
 810			 * The poll work sets force=false when calling detect so
 811			 * that drivers can avoid to do disruptive tests (e.g.
 812			 * when load detect cycles could cause flickering on
 813			 * other, running displays). This bears the risk that we
 814			 * flip-flop between unknown here in the poll work and
 815			 * the real state when userspace forces a full detect
 816			 * call after receiving a hotplug event due to this
 817			 * change.
 818			 *
 819			 * Hence clamp an unknown detect status to the old
 820			 * value.
 821			 */
 822			if (connector->status == connector_status_unknown) {
 823				connector->status = old_status;
 824				continue;
 825			}
 826
 827			old = drm_get_connector_status_name(old_status);
 828			new = drm_get_connector_status_name(connector->status);
 829
 830			drm_dbg_kms(dev, "[CONNECTOR:%d:%s] status updated from %s to %s\n",
 831				    connector->base.id, connector->name,
 832				    old, new);
 833			drm_dbg_kms(dev, "[CONNECTOR:%d:%s] epoch counter %llu -> %llu\n",
 834				    connector->base.id, connector->name,
 835				    old_epoch_counter, connector->epoch_counter);
 
 
 836
 837			changed = true;
 838		}
 839	}
 840	drm_connector_list_iter_end(&conn_iter);
 841
 842	mutex_unlock(&dev->mode_config.mutex);
 843
 844out:
 845	if (changed)
 846		drm_kms_helper_hotplug_event(dev);
 847
 848	if (repoll)
 849		schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD);
 850}
 851
 852/**
 853 * drm_kms_helper_is_poll_worker - is %current task an output poll worker?
 854 *
 855 * Determine if %current task is an output poll worker.  This can be used
 856 * to select distinct code paths for output polling versus other contexts.
 857 *
 858 * One use case is to avoid a deadlock between the output poll worker and
 859 * the autosuspend worker wherein the latter waits for polling to finish
 860 * upon calling drm_kms_helper_poll_disable(), while the former waits for
 861 * runtime suspend to finish upon calling pm_runtime_get_sync() in a
 862 * connector ->detect hook.
 863 */
 864bool drm_kms_helper_is_poll_worker(void)
 865{
 866	struct work_struct *work = current_work();
 867
 868	return work && work->func == output_poll_execute;
 869}
 870EXPORT_SYMBOL(drm_kms_helper_is_poll_worker);
 871
 872/**
 873 * drm_kms_helper_poll_disable - disable output polling
 874 * @dev: drm_device
 875 *
 876 * This function disables the output polling work.
 877 *
 878 * Drivers can call this helper from their device suspend implementation. It is
 879 * not an error to call this even when output polling isn't enabled or already
 880 * disabled. Polling is re-enabled by calling drm_kms_helper_poll_enable().
 881 *
 882 * If however, the polling was never initialized, this call will trigger a
 883 * warning and return.
 884 *
 885 * Note that calls to enable and disable polling must be strictly ordered, which
 886 * is automatically the case when they're only call from suspend/resume
 887 * callbacks.
 888 */
 889void drm_kms_helper_poll_disable(struct drm_device *dev)
 890{
 891	if (drm_WARN_ON(dev, !dev->mode_config.poll_enabled))
 892		return;
 893
 894	if (dev->mode_config.poll_running)
 895		drm_kms_helper_disable_hpd(dev);
 896
 897	cancel_delayed_work_sync(&dev->mode_config.output_poll_work);
 898
 899	dev->mode_config.poll_running = false;
 900}
 901EXPORT_SYMBOL(drm_kms_helper_poll_disable);
 902
 903/**
 904 * drm_kms_helper_poll_init - initialize and enable output polling
 905 * @dev: drm_device
 906 *
 907 * This function initializes and then also enables output polling support for
 908 * @dev. Drivers which do not have reliable hotplug support in hardware can use
 909 * this helper infrastructure to regularly poll such connectors for changes in
 910 * their connection state.
 911 *
 912 * Drivers can control which connectors are polled by setting the
 913 * DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On
 914 * connectors where probing live outputs can result in visual distortion drivers
 915 * should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this.
 916 * Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are
 917 * completely ignored by the polling logic.
 918 *
 919 * Note that a connector can be both polled and probed from the hotplug handler,
 920 * in case the hotplug interrupt is known to be unreliable.
 921 */
 922void drm_kms_helper_poll_init(struct drm_device *dev)
 923{
 924	INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);
 925	dev->mode_config.poll_enabled = true;
 926
 927	drm_kms_helper_poll_enable(dev);
 928}
 929EXPORT_SYMBOL(drm_kms_helper_poll_init);
 930
 931/**
 932 * drm_kms_helper_poll_fini - disable output polling and clean it up
 933 * @dev: drm_device
 934 */
 935void drm_kms_helper_poll_fini(struct drm_device *dev)
 936{
 937	if (!dev->mode_config.poll_enabled)
 938		return;
 939
 940	drm_kms_helper_poll_disable(dev);
 941
 942	dev->mode_config.poll_enabled = false;
 943}
 944EXPORT_SYMBOL(drm_kms_helper_poll_fini);
 945
 946static void drm_kms_helper_poll_init_release(struct drm_device *dev, void *res)
 947{
 948	drm_kms_helper_poll_fini(dev);
 949}
 950
 951/**
 952 * drmm_kms_helper_poll_init - initialize and enable output polling
 953 * @dev: drm_device
 954 *
 955 * This function initializes and then also enables output polling support for
 956 * @dev similar to drm_kms_helper_poll_init(). Polling will automatically be
 957 * cleaned up when the DRM device goes away.
 958 *
 959 * See drm_kms_helper_poll_init() for more information.
 960 *
 961 * Returns:
 962 * 0 on success, or a negative errno code otherwise.
 963 */
 964int drmm_kms_helper_poll_init(struct drm_device *dev)
 965{
 966	drm_kms_helper_poll_init(dev);
 967
 968	return drmm_add_action_or_reset(dev, drm_kms_helper_poll_init_release, dev);
 969}
 970EXPORT_SYMBOL(drmm_kms_helper_poll_init);
 971
 972static bool check_connector_changed(struct drm_connector *connector)
 973{
 974	struct drm_device *dev = connector->dev;
 975	enum drm_connector_status old_status;
 976	u64 old_epoch_counter;
 977
 978	/* Only handle HPD capable connectors. */
 979	drm_WARN_ON(dev, !(connector->polled & DRM_CONNECTOR_POLL_HPD));
 980
 981	drm_WARN_ON(dev, !mutex_is_locked(&dev->mode_config.mutex));
 982
 983	old_status = connector->status;
 984	old_epoch_counter = connector->epoch_counter;
 985	connector->status = drm_helper_probe_detect(connector, NULL, false);
 986
 987	if (old_epoch_counter == connector->epoch_counter) {
 988		drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Same epoch counter %llu\n",
 989			    connector->base.id,
 990			    connector->name,
 991			    connector->epoch_counter);
 992
 993		return false;
 994	}
 995
 996	drm_dbg_kms(dev, "[CONNECTOR:%d:%s] status updated from %s to %s\n",
 997		    connector->base.id,
 998		    connector->name,
 999		    drm_get_connector_status_name(old_status),
1000		    drm_get_connector_status_name(connector->status));
1001
1002	drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Changed epoch counter %llu => %llu\n",
1003		    connector->base.id,
1004		    connector->name,
1005		    old_epoch_counter,
1006		    connector->epoch_counter);
1007
1008	return true;
1009}
1010
1011/**
1012 * drm_connector_helper_hpd_irq_event - hotplug processing
1013 * @connector: drm_connector
1014 *
1015 * Drivers can use this helper function to run a detect cycle on a connector
1016 * which has the DRM_CONNECTOR_POLL_HPD flag set in its &polled member.
1017 *
1018 * This helper function is useful for drivers which can track hotplug
1019 * interrupts for a single connector. Drivers that want to send a
1020 * hotplug event for all connectors or can't track hotplug interrupts
1021 * per connector need to use drm_helper_hpd_irq_event().
1022 *
1023 * This function must be called from process context with no mode
1024 * setting locks held.
1025 *
1026 * Note that a connector can be both polled and probed from the hotplug
1027 * handler, in case the hotplug interrupt is known to be unreliable.
1028 *
1029 * Returns:
1030 * A boolean indicating whether the connector status changed or not
1031 */
1032bool drm_connector_helper_hpd_irq_event(struct drm_connector *connector)
1033{
1034	struct drm_device *dev = connector->dev;
1035	bool changed;
1036
1037	mutex_lock(&dev->mode_config.mutex);
1038	changed = check_connector_changed(connector);
1039	mutex_unlock(&dev->mode_config.mutex);
1040
1041	if (changed) {
1042		drm_kms_helper_connector_hotplug_event(connector);
1043		drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Sent hotplug event\n",
1044			    connector->base.id,
1045			    connector->name);
1046	}
1047
1048	return changed;
1049}
1050EXPORT_SYMBOL(drm_connector_helper_hpd_irq_event);
1051
1052/**
1053 * drm_helper_hpd_irq_event - hotplug processing
1054 * @dev: drm_device
1055 *
1056 * Drivers can use this helper function to run a detect cycle on all connectors
1057 * which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All
1058 * other connectors are ignored, which is useful to avoid reprobing fixed
1059 * panels.
1060 *
1061 * This helper function is useful for drivers which can't or don't track hotplug
1062 * interrupts for each connector.
1063 *
1064 * Drivers which support hotplug interrupts for each connector individually and
1065 * which have a more fine-grained detect logic can use
1066 * drm_connector_helper_hpd_irq_event(). Alternatively, they should bypass this
1067 * code and directly call drm_kms_helper_hotplug_event() in case the connector
1068 * state changed.
1069 *
1070 * This function must be called from process context with no mode
1071 * setting locks held.
1072 *
1073 * Note that a connector can be both polled and probed from the hotplug handler,
1074 * in case the hotplug interrupt is known to be unreliable.
1075 *
1076 * Returns:
1077 * A boolean indicating whether the connector status changed or not
1078 */
1079bool drm_helper_hpd_irq_event(struct drm_device *dev)
1080{
1081	struct drm_connector *connector, *first_changed_connector = NULL;
1082	struct drm_connector_list_iter conn_iter;
1083	int changed = 0;
1084
1085	if (!dev->mode_config.poll_enabled)
1086		return false;
1087
1088	mutex_lock(&dev->mode_config.mutex);
1089	drm_connector_list_iter_begin(dev, &conn_iter);
1090	drm_for_each_connector_iter(connector, &conn_iter) {
1091		/* Only handle HPD capable connectors. */
1092		if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))
1093			continue;
1094
1095		if (check_connector_changed(connector)) {
1096			if (!first_changed_connector) {
1097				drm_connector_get(connector);
1098				first_changed_connector = connector;
1099			}
1100
1101			changed++;
1102		}
1103	}
1104	drm_connector_list_iter_end(&conn_iter);
1105	mutex_unlock(&dev->mode_config.mutex);
1106
1107	if (changed == 1)
1108		drm_kms_helper_connector_hotplug_event(first_changed_connector);
1109	else if (changed > 0)
1110		drm_kms_helper_hotplug_event(dev);
1111
1112	if (first_changed_connector)
1113		drm_connector_put(first_changed_connector);
1114
1115	return changed;
1116}
1117EXPORT_SYMBOL(drm_helper_hpd_irq_event);
1118
1119/**
1120 * drm_crtc_helper_mode_valid_fixed - Validates a display mode
1121 * @crtc: the crtc
1122 * @mode: the mode to validate
1123 * @fixed_mode: the display hardware's mode
1124 *
1125 * Returns:
1126 * MODE_OK on success, or another mode-status code otherwise.
1127 */
1128enum drm_mode_status drm_crtc_helper_mode_valid_fixed(struct drm_crtc *crtc,
1129						      const struct drm_display_mode *mode,
1130						      const struct drm_display_mode *fixed_mode)
1131{
1132	if (mode->hdisplay != fixed_mode->hdisplay && mode->vdisplay != fixed_mode->vdisplay)
1133		return MODE_ONE_SIZE;
1134	else if (mode->hdisplay != fixed_mode->hdisplay)
1135		return MODE_ONE_WIDTH;
1136	else if (mode->vdisplay != fixed_mode->vdisplay)
1137		return MODE_ONE_HEIGHT;
1138
1139	return MODE_OK;
1140}
1141EXPORT_SYMBOL(drm_crtc_helper_mode_valid_fixed);
1142
1143/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1144 * drm_connector_helper_get_modes_fixed - Duplicates a display mode for a connector
1145 * @connector: the connector
1146 * @fixed_mode: the display hardware's mode
1147 *
1148 * This function duplicates a display modes for a connector. Drivers for hardware
1149 * that only supports a single fixed mode can use this function in their connector's
1150 * get_modes helper.
1151 *
1152 * Returns:
1153 * The number of created modes.
1154 */
1155int drm_connector_helper_get_modes_fixed(struct drm_connector *connector,
1156					 const struct drm_display_mode *fixed_mode)
1157{
1158	struct drm_device *dev = connector->dev;
1159	struct drm_display_mode *mode;
1160
1161	mode = drm_mode_duplicate(dev, fixed_mode);
1162	if (!mode) {
1163		drm_err(dev, "Failed to duplicate mode " DRM_MODE_FMT "\n",
1164			DRM_MODE_ARG(fixed_mode));
1165		return 0;
1166	}
1167
1168	if (mode->name[0] == '\0')
1169		drm_mode_set_name(mode);
1170
1171	mode->type |= DRM_MODE_TYPE_PREFERRED;
1172	drm_mode_probed_add(connector, mode);
1173
1174	if (mode->width_mm)
1175		connector->display_info.width_mm = mode->width_mm;
1176	if (mode->height_mm)
1177		connector->display_info.height_mm = mode->height_mm;
1178
1179	return 1;
1180}
1181EXPORT_SYMBOL(drm_connector_helper_get_modes_fixed);
1182
1183/**
1184 * drm_connector_helper_get_modes - Read EDID and update connector.
1185 * @connector: The connector
1186 *
1187 * Read the EDID using drm_edid_read() (which requires that connector->ddc is
1188 * set), and update the connector using the EDID.
1189 *
1190 * This can be used as the "default" connector helper .get_modes() hook if the
1191 * driver does not need any special processing. This is sets the example what
1192 * custom .get_modes() hooks should do regarding EDID read and connector update.
1193 *
1194 * Returns: Number of modes.
1195 */
1196int drm_connector_helper_get_modes(struct drm_connector *connector)
1197{
1198	const struct drm_edid *drm_edid;
1199	int count;
1200
1201	drm_edid = drm_edid_read(connector);
1202
1203	/*
1204	 * Unconditionally update the connector. If the EDID was read
1205	 * successfully, fill in the connector information derived from the
1206	 * EDID. Otherwise, if the EDID is NULL, clear the connector
1207	 * information.
1208	 */
1209	drm_edid_connector_update(connector, drm_edid);
1210
1211	count = drm_edid_connector_add_modes(connector);
1212
1213	drm_edid_free(drm_edid);
1214
1215	return count;
1216}
1217EXPORT_SYMBOL(drm_connector_helper_get_modes);
1218
1219/**
1220 * drm_connector_helper_tv_get_modes - Fills the modes availables to a TV connector
1221 * @connector: The connector
1222 *
1223 * Fills the available modes for a TV connector based on the supported
1224 * TV modes, and the default mode expressed by the kernel command line.
1225 *
1226 * This can be used as the default TV connector helper .get_modes() hook
1227 * if the driver does not need any special processing.
1228 *
1229 * Returns:
1230 * The number of modes added to the connector.
1231 */
1232int drm_connector_helper_tv_get_modes(struct drm_connector *connector)
1233{
1234	struct drm_device *dev = connector->dev;
1235	struct drm_property *tv_mode_property =
1236		dev->mode_config.tv_mode_property;
1237	struct drm_cmdline_mode *cmdline = &connector->cmdline_mode;
1238	unsigned int ntsc_modes = BIT(DRM_MODE_TV_MODE_NTSC) |
1239		BIT(DRM_MODE_TV_MODE_NTSC_443) |
1240		BIT(DRM_MODE_TV_MODE_NTSC_J) |
1241		BIT(DRM_MODE_TV_MODE_PAL_M);
1242	unsigned int pal_modes = BIT(DRM_MODE_TV_MODE_PAL) |
1243		BIT(DRM_MODE_TV_MODE_PAL_N) |
1244		BIT(DRM_MODE_TV_MODE_SECAM);
1245	unsigned int tv_modes[2] = { UINT_MAX, UINT_MAX };
1246	unsigned int i, supported_tv_modes = 0;
1247
1248	if (!tv_mode_property)
1249		return 0;
1250
1251	for (i = 0; i < tv_mode_property->num_values; i++)
1252		supported_tv_modes |= BIT(tv_mode_property->values[i]);
1253
1254	if (((supported_tv_modes & ntsc_modes) &&
1255	     (supported_tv_modes & pal_modes)) ||
1256	    (supported_tv_modes & BIT(DRM_MODE_TV_MODE_MONOCHROME))) {
1257		uint64_t default_mode;
1258
1259		if (drm_object_property_get_default_value(&connector->base,
1260							  tv_mode_property,
1261							  &default_mode))
1262			return 0;
1263
1264		if (cmdline->tv_mode_specified)
1265			default_mode = cmdline->tv_mode;
1266
1267		if (BIT(default_mode) & ntsc_modes) {
1268			tv_modes[0] = DRM_MODE_TV_MODE_NTSC;
1269			tv_modes[1] = DRM_MODE_TV_MODE_PAL;
1270		} else {
1271			tv_modes[0] = DRM_MODE_TV_MODE_PAL;
1272			tv_modes[1] = DRM_MODE_TV_MODE_NTSC;
1273		}
1274	} else if (supported_tv_modes & ntsc_modes) {
1275		tv_modes[0] = DRM_MODE_TV_MODE_NTSC;
1276	} else if (supported_tv_modes & pal_modes) {
1277		tv_modes[0] = DRM_MODE_TV_MODE_PAL;
1278	} else {
1279		return 0;
1280	}
1281
1282	for (i = 0; i < ARRAY_SIZE(tv_modes); i++) {
1283		struct drm_display_mode *mode;
1284
1285		if (tv_modes[i] == DRM_MODE_TV_MODE_NTSC)
1286			mode = drm_mode_analog_ntsc_480i(dev);
1287		else if (tv_modes[i] == DRM_MODE_TV_MODE_PAL)
1288			mode = drm_mode_analog_pal_576i(dev);
1289		else
1290			break;
1291		if (!mode)
1292			return i;
1293		if (!i)
1294			mode->type |= DRM_MODE_TYPE_PREFERRED;
1295		drm_mode_probed_add(connector, mode);
1296	}
1297
1298	return i;
1299}
1300EXPORT_SYMBOL(drm_connector_helper_tv_get_modes);
1301
1302/**
1303 * drm_connector_helper_detect_from_ddc - Read EDID and detect connector status.
1304 * @connector: The connector
1305 * @ctx: Acquire context
1306 * @force: Perform screen-destructive operations, if necessary
1307 *
1308 * Detects the connector status by reading the EDID using drm_probe_ddc(),
1309 * which requires connector->ddc to be set. Returns connector_status_connected
1310 * on success or connector_status_disconnected on failure.
1311 *
1312 * Returns:
1313 * The connector status as defined by enum drm_connector_status.
1314 */
1315int drm_connector_helper_detect_from_ddc(struct drm_connector *connector,
1316					 struct drm_modeset_acquire_ctx *ctx,
1317					 bool force)
1318{
1319	struct i2c_adapter *ddc = connector->ddc;
1320
1321	if (!ddc)
1322		return connector_status_unknown;
1323
1324	if (drm_probe_ddc(ddc))
1325		return connector_status_connected;
1326
1327	return connector_status_disconnected;
1328}
1329EXPORT_SYMBOL(drm_connector_helper_detect_from_ddc);