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v5.4
   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/kernel.h>
  34#include <linux/moduleparam.h>
 
  35
  36#include <drm/drm_atomic.h>
  37#include <drm/drm_atomic_helper.h>
  38#include <drm/drm_atomic_uapi.h>
 
  39#include <drm/drm_crtc.h>
  40#include <drm/drm_crtc_helper.h>
  41#include <drm/drm_drv.h>
  42#include <drm/drm_edid.h>
  43#include <drm/drm_encoder.h>
  44#include <drm/drm_fb_helper.h>
  45#include <drm/drm_fourcc.h>
  46#include <drm/drm_plane_helper.h>
  47#include <drm/drm_print.h>
  48#include <drm/drm_vblank.h>
  49
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  50/**
  51 * DOC: overview
  52 *
  53 * The CRTC modeset helper library provides a default set_config implementation
  54 * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
  55 * the same callbacks which drivers can use to e.g. restore the modeset
  56 * configuration on resume with drm_helper_resume_force_mode().
  57 *
  58 * Note that this helper library doesn't track the current power state of CRTCs
  59 * and encoders. It can call callbacks like &drm_encoder_helper_funcs.dpms even
  60 * though the hardware is already in the desired state. This deficiency has been
  61 * fixed in the atomic helpers.
  62 *
  63 * The driver callbacks are mostly compatible with the atomic modeset helpers,
  64 * except for the handling of the primary plane: Atomic helpers require that the
  65 * primary plane is implemented as a real standalone plane and not directly tied
  66 * to the CRTC state. For easier transition this library provides functions to
  67 * implement the old semantics required by the CRTC helpers using the new plane
  68 * and atomic helper callbacks.
  69 *
  70 * Drivers are strongly urged to convert to the atomic helpers (by way of first
  71 * converting to the plane helpers). New drivers must not use these functions
  72 * but need to implement the atomic interface instead, potentially using the
  73 * atomic helpers for that.
  74 *
  75 * These legacy modeset helpers use the same function table structures as
  76 * all other modesetting helpers. See the documentation for struct
  77 * &drm_crtc_helper_funcs, &struct drm_encoder_helper_funcs and struct
  78 * &drm_connector_helper_funcs.
  79 */
  80
  81/**
  82 * drm_helper_encoder_in_use - check if a given encoder is in use
  83 * @encoder: encoder to check
  84 *
  85 * Checks whether @encoder is with the current mode setting output configuration
  86 * in use by any connector. This doesn't mean that it is actually enabled since
  87 * the DPMS state is tracked separately.
  88 *
  89 * Returns:
  90 * True if @encoder is used, false otherwise.
  91 */
  92bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
  93{
  94	struct drm_connector *connector;
  95	struct drm_connector_list_iter conn_iter;
  96	struct drm_device *dev = encoder->dev;
  97
  98	WARN_ON(drm_drv_uses_atomic_modeset(dev));
  99
 100	/*
 101	 * We can expect this mutex to be locked if we are not panicking.
 102	 * Locking is currently fubar in the panic handler.
 103	 */
 104	if (!oops_in_progress) {
 105		WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 106		WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 107	}
 108
 109
 110	drm_connector_list_iter_begin(dev, &conn_iter);
 111	drm_for_each_connector_iter(connector, &conn_iter) {
 112		if (connector->encoder == encoder) {
 113			drm_connector_list_iter_end(&conn_iter);
 114			return true;
 115		}
 116	}
 117	drm_connector_list_iter_end(&conn_iter);
 118	return false;
 119}
 120EXPORT_SYMBOL(drm_helper_encoder_in_use);
 121
 122/**
 123 * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 124 * @crtc: CRTC to check
 125 *
 126 * Checks whether @crtc is with the current mode setting output configuration
 127 * in use by any connector. This doesn't mean that it is actually enabled since
 128 * the DPMS state is tracked separately.
 129 *
 130 * Returns:
 131 * True if @crtc is used, false otherwise.
 132 */
 133bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 134{
 135	struct drm_encoder *encoder;
 136	struct drm_device *dev = crtc->dev;
 137
 138	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 139
 140	/*
 141	 * We can expect this mutex to be locked if we are not panicking.
 142	 * Locking is currently fubar in the panic handler.
 143	 */
 144	if (!oops_in_progress)
 145		WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 146
 147	drm_for_each_encoder(encoder, dev)
 148		if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 149			return true;
 150	return false;
 151}
 152EXPORT_SYMBOL(drm_helper_crtc_in_use);
 153
 154static void
 155drm_encoder_disable(struct drm_encoder *encoder)
 156{
 157	const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 158
 159	if (!encoder_funcs)
 160		return;
 161
 162	if (encoder_funcs->disable)
 163		(*encoder_funcs->disable)(encoder);
 164	else if (encoder_funcs->dpms)
 165		(*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 166}
 167
 168static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 169{
 170	struct drm_encoder *encoder;
 171	struct drm_crtc *crtc;
 172
 173	drm_warn_on_modeset_not_all_locked(dev);
 174
 175	drm_for_each_encoder(encoder, dev) {
 176		if (!drm_helper_encoder_in_use(encoder)) {
 177			drm_encoder_disable(encoder);
 178			/* disconnect encoder from any connector */
 179			encoder->crtc = NULL;
 180		}
 181	}
 182
 183	drm_for_each_crtc(crtc, dev) {
 184		const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 
 185		crtc->enabled = drm_helper_crtc_in_use(crtc);
 186		if (!crtc->enabled) {
 187			if (crtc_funcs->disable)
 188				(*crtc_funcs->disable)(crtc);
 189			else
 190				(*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 191			crtc->primary->fb = NULL;
 192		}
 193	}
 194}
 195
 196/**
 197 * drm_helper_disable_unused_functions - disable unused objects
 198 * @dev: DRM device
 199 *
 200 * This function walks through the entire mode setting configuration of @dev. It
 201 * will remove any CRTC links of unused encoders and encoder links of
 202 * disconnected connectors. Then it will disable all unused encoders and CRTCs
 203 * either by calling their disable callback if available or by calling their
 204 * dpms callback with DRM_MODE_DPMS_OFF.
 205 *
 206 * NOTE:
 207 *
 208 * This function is part of the legacy modeset helper library and will cause
 209 * major confusion with atomic drivers. This is because atomic helpers guarantee
 210 * to never call ->disable() hooks on a disabled function, or ->enable() hooks
 211 * on an enabled functions. drm_helper_disable_unused_functions() on the other
 212 * hand throws such guarantees into the wind and calls disable hooks
 213 * unconditionally on unused functions.
 214 */
 215void drm_helper_disable_unused_functions(struct drm_device *dev)
 216{
 217	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 218
 219	drm_modeset_lock_all(dev);
 220	__drm_helper_disable_unused_functions(dev);
 221	drm_modeset_unlock_all(dev);
 222}
 223EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 224
 225/*
 226 * Check the CRTC we're going to map each output to vs. its current
 227 * CRTC.  If they don't match, we have to disable the output and the CRTC
 228 * since the driver will have to re-route things.
 229 */
 230static void
 231drm_crtc_prepare_encoders(struct drm_device *dev)
 232{
 233	const struct drm_encoder_helper_funcs *encoder_funcs;
 234	struct drm_encoder *encoder;
 235
 236	drm_for_each_encoder(encoder, dev) {
 237		encoder_funcs = encoder->helper_private;
 238		if (!encoder_funcs)
 239			continue;
 240
 241		/* Disable unused encoders */
 242		if (encoder->crtc == NULL)
 243			drm_encoder_disable(encoder);
 244		/* Disable encoders whose CRTC is about to change */
 245		if (encoder_funcs->get_crtc &&
 246		    encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
 247			drm_encoder_disable(encoder);
 248	}
 249}
 250
 251/**
 252 * drm_crtc_helper_set_mode - internal helper to set a mode
 253 * @crtc: CRTC to program
 254 * @mode: mode to use
 255 * @x: horizontal offset into the surface
 256 * @y: vertical offset into the surface
 257 * @old_fb: old framebuffer, for cleanup
 258 *
 259 * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 260 * to fixup or reject the mode prior to trying to set it. This is an internal
 261 * helper that drivers could e.g. use to update properties that require the
 262 * entire output pipe to be disabled and re-enabled in a new configuration. For
 263 * example for changing whether audio is enabled on a hdmi link or for changing
 264 * panel fitter or dither attributes. It is also called by the
 265 * drm_crtc_helper_set_config() helper function to drive the mode setting
 266 * sequence.
 267 *
 268 * Returns:
 269 * True if the mode was set successfully, false otherwise.
 270 */
 271bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 272			      struct drm_display_mode *mode,
 273			      int x, int y,
 274			      struct drm_framebuffer *old_fb)
 275{
 276	struct drm_device *dev = crtc->dev;
 277	struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
 278	const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 279	const struct drm_encoder_helper_funcs *encoder_funcs;
 280	int saved_x, saved_y;
 281	bool saved_enabled;
 282	struct drm_encoder *encoder;
 283	bool ret = true;
 284
 285	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 286
 287	drm_warn_on_modeset_not_all_locked(dev);
 288
 289	saved_enabled = crtc->enabled;
 290	crtc->enabled = drm_helper_crtc_in_use(crtc);
 291	if (!crtc->enabled)
 292		return true;
 293
 294	adjusted_mode = drm_mode_duplicate(dev, mode);
 295	if (!adjusted_mode) {
 296		crtc->enabled = saved_enabled;
 297		return false;
 298	}
 299
 300	saved_mode = crtc->mode;
 301	saved_hwmode = crtc->hwmode;
 302	saved_x = crtc->x;
 303	saved_y = crtc->y;
 304
 305	/* Update crtc values up front so the driver can rely on them for mode
 306	 * setting.
 307	 */
 308	crtc->mode = *mode;
 309	crtc->x = x;
 310	crtc->y = y;
 311
 312	/* Pass our mode to the connectors and the CRTC to give them a chance to
 313	 * adjust it according to limitations or connector properties, and also
 314	 * a chance to reject the mode entirely.
 315	 */
 316	drm_for_each_encoder(encoder, dev) {
 317
 318		if (encoder->crtc != crtc)
 319			continue;
 320
 321		encoder_funcs = encoder->helper_private;
 322		if (!encoder_funcs)
 323			continue;
 324
 325		encoder_funcs = encoder->helper_private;
 326		if (encoder_funcs->mode_fixup) {
 327			if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 328							      adjusted_mode))) {
 329				DRM_DEBUG_KMS("Encoder fixup failed\n");
 330				goto done;
 331			}
 332		}
 333	}
 334
 335	if (crtc_funcs->mode_fixup) {
 336		if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
 337						adjusted_mode))) {
 338			DRM_DEBUG_KMS("CRTC fixup failed\n");
 339			goto done;
 340		}
 341	}
 342	DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
 343
 344	crtc->hwmode = *adjusted_mode;
 345
 346	/* Prepare the encoders and CRTCs before setting the mode. */
 347	drm_for_each_encoder(encoder, dev) {
 348
 349		if (encoder->crtc != crtc)
 350			continue;
 351
 352		encoder_funcs = encoder->helper_private;
 353		if (!encoder_funcs)
 354			continue;
 355
 356		/* Disable the encoders as the first thing we do. */
 357		if (encoder_funcs->prepare)
 358			encoder_funcs->prepare(encoder);
 359	}
 360
 361	drm_crtc_prepare_encoders(dev);
 362
 363	crtc_funcs->prepare(crtc);
 364
 365	/* Set up the DPLL and any encoders state that needs to adjust or depend
 366	 * on the DPLL.
 367	 */
 368	ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 369	if (!ret)
 370	    goto done;
 371
 372	drm_for_each_encoder(encoder, dev) {
 373
 374		if (encoder->crtc != crtc)
 375			continue;
 376
 377		encoder_funcs = encoder->helper_private;
 378		if (!encoder_funcs)
 379			continue;
 380
 381		DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%s]\n",
 382			encoder->base.id, encoder->name, mode->name);
 383		if (encoder_funcs->mode_set)
 384			encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 385	}
 386
 387	/* Now enable the clocks, plane, pipe, and connectors that we set up. */
 388	crtc_funcs->commit(crtc);
 389
 390	drm_for_each_encoder(encoder, dev) {
 391
 392		if (encoder->crtc != crtc)
 393			continue;
 394
 395		encoder_funcs = encoder->helper_private;
 396		if (!encoder_funcs)
 397			continue;
 398
 399		if (encoder_funcs->commit)
 400			encoder_funcs->commit(encoder);
 401	}
 402
 403	/* Calculate and store various constants which
 404	 * are later needed by vblank and swap-completion
 405	 * timestamping. They are derived from true hwmode.
 406	 */
 407	drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 408
 409	/* FIXME: add subpixel order */
 410done:
 411	drm_mode_destroy(dev, adjusted_mode);
 412	if (!ret) {
 413		crtc->enabled = saved_enabled;
 414		crtc->mode = saved_mode;
 415		crtc->hwmode = saved_hwmode;
 416		crtc->x = saved_x;
 417		crtc->y = saved_y;
 418	}
 419
 420	return ret;
 421}
 422EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 423
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 424static void
 425drm_crtc_helper_disable(struct drm_crtc *crtc)
 426{
 427	struct drm_device *dev = crtc->dev;
 428	struct drm_connector *connector;
 429	struct drm_encoder *encoder;
 430
 431	/* Decouple all encoders and their attached connectors from this crtc */
 432	drm_for_each_encoder(encoder, dev) {
 433		struct drm_connector_list_iter conn_iter;
 434
 435		if (encoder->crtc != crtc)
 436			continue;
 437
 438		drm_connector_list_iter_begin(dev, &conn_iter);
 439		drm_for_each_connector_iter(connector, &conn_iter) {
 440			if (connector->encoder != encoder)
 441				continue;
 442
 443			connector->encoder = NULL;
 444
 445			/*
 446			 * drm_helper_disable_unused_functions() ought to be
 447			 * doing this, but since we've decoupled the encoder
 448			 * from the connector above, the required connection
 449			 * between them is henceforth no longer available.
 450			 */
 451			connector->dpms = DRM_MODE_DPMS_OFF;
 452
 453			/* we keep a reference while the encoder is bound */
 454			drm_connector_put(connector);
 455		}
 456		drm_connector_list_iter_end(&conn_iter);
 457	}
 458
 459	__drm_helper_disable_unused_functions(dev);
 460}
 461
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 462/**
 463 * drm_crtc_helper_set_config - set a new config from userspace
 464 * @set: mode set configuration
 465 * @ctx: lock acquire context, not used here
 466 *
 467 * The drm_crtc_helper_set_config() helper function implements the of
 468 * &drm_crtc_funcs.set_config callback for drivers using the legacy CRTC
 469 * helpers.
 470 *
 471 * It first tries to locate the best encoder for each connector by calling the
 472 * connector @drm_connector_helper_funcs.best_encoder helper operation.
 473 *
 474 * After locating the appropriate encoders, the helper function will call the
 475 * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
 476 * or reject it completely in which case an error will be returned to the
 477 * application. If the new configuration after mode adjustment is identical to
 478 * the current configuration the helper function will return without performing
 479 * any other operation.
 480 *
 481 * If the adjusted mode is identical to the current mode but changes to the
 482 * frame buffer need to be applied, the drm_crtc_helper_set_config() function
 483 * will call the CRTC &drm_crtc_helper_funcs.mode_set_base helper operation.
 484 *
 485 * If the adjusted mode differs from the current mode, or if the
 486 * ->mode_set_base() helper operation is not provided, the helper function
 487 * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
 488 * and ->commit() CRTC and encoder helper operations, in that order.
 489 * Alternatively it can also use the dpms and disable helper operations. For
 490 * details see &struct drm_crtc_helper_funcs and struct
 491 * &drm_encoder_helper_funcs.
 492 *
 493 * This function is deprecated.  New drivers must implement atomic modeset
 494 * support, for which this function is unsuitable. Instead drivers should use
 495 * drm_atomic_helper_set_config().
 496 *
 497 * Returns:
 498 * Returns 0 on success, negative errno numbers on failure.
 499 */
 500int drm_crtc_helper_set_config(struct drm_mode_set *set,
 501			       struct drm_modeset_acquire_ctx *ctx)
 502{
 503	struct drm_device *dev;
 504	struct drm_crtc **save_encoder_crtcs, *new_crtc;
 505	struct drm_encoder **save_connector_encoders, *new_encoder, *encoder;
 506	bool mode_changed = false; /* if true do a full mode set */
 507	bool fb_changed = false; /* if true and !mode_changed just do a flip */
 508	struct drm_connector *connector;
 509	struct drm_connector_list_iter conn_iter;
 510	int count = 0, ro, fail = 0;
 511	const struct drm_crtc_helper_funcs *crtc_funcs;
 512	struct drm_mode_set save_set;
 513	int ret;
 514	int i;
 515
 516	DRM_DEBUG_KMS("\n");
 517
 518	BUG_ON(!set);
 519	BUG_ON(!set->crtc);
 520	BUG_ON(!set->crtc->helper_private);
 521
 522	/* Enforce sane interface api - has been abused by the fb helper. */
 523	BUG_ON(!set->mode && set->fb);
 524	BUG_ON(set->fb && set->num_connectors == 0);
 525
 526	crtc_funcs = set->crtc->helper_private;
 527
 528	dev = set->crtc->dev;
 529	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 530
 531	if (!set->mode)
 532		set->fb = NULL;
 533
 534	if (set->fb) {
 535		DRM_DEBUG_KMS("[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 536			      set->crtc->base.id, set->crtc->name,
 537			      set->fb->base.id,
 538			      (int)set->num_connectors, set->x, set->y);
 539	} else {
 540		DRM_DEBUG_KMS("[CRTC:%d:%s] [NOFB]\n",
 541			      set->crtc->base.id, set->crtc->name);
 542		drm_crtc_helper_disable(set->crtc);
 543		return 0;
 544	}
 545
 546	drm_warn_on_modeset_not_all_locked(dev);
 547
 548	/*
 549	 * Allocate space for the backup of all (non-pointer) encoder and
 550	 * connector data.
 551	 */
 552	save_encoder_crtcs = kcalloc(dev->mode_config.num_encoder,
 553				sizeof(struct drm_crtc *), GFP_KERNEL);
 554	if (!save_encoder_crtcs)
 555		return -ENOMEM;
 556
 557	save_connector_encoders = kcalloc(dev->mode_config.num_connector,
 558				sizeof(struct drm_encoder *), GFP_KERNEL);
 559	if (!save_connector_encoders) {
 560		kfree(save_encoder_crtcs);
 561		return -ENOMEM;
 562	}
 563
 564	/*
 565	 * Copy data. Note that driver private data is not affected.
 566	 * Should anything bad happen only the expected state is
 567	 * restored, not the drivers personal bookkeeping.
 568	 */
 569	count = 0;
 570	drm_for_each_encoder(encoder, dev) {
 571		save_encoder_crtcs[count++] = encoder->crtc;
 572	}
 573
 574	count = 0;
 575	drm_connector_list_iter_begin(dev, &conn_iter);
 576	drm_for_each_connector_iter(connector, &conn_iter)
 577		save_connector_encoders[count++] = connector->encoder;
 578	drm_connector_list_iter_end(&conn_iter);
 579
 580	save_set.crtc = set->crtc;
 581	save_set.mode = &set->crtc->mode;
 582	save_set.x = set->crtc->x;
 583	save_set.y = set->crtc->y;
 584	save_set.fb = set->crtc->primary->fb;
 585
 586	/* We should be able to check here if the fb has the same properties
 587	 * and then just flip_or_move it */
 588	if (set->crtc->primary->fb != set->fb) {
 589		/* If we have no fb then treat it as a full mode set */
 590		if (set->crtc->primary->fb == NULL) {
 591			DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 592			mode_changed = true;
 593		} else if (set->fb->format != set->crtc->primary->fb->format) {
 594			mode_changed = true;
 595		} else
 596			fb_changed = true;
 597	}
 598
 599	if (set->x != set->crtc->x || set->y != set->crtc->y)
 600		fb_changed = true;
 601
 602	if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
 603		DRM_DEBUG_KMS("modes are different, full mode set\n");
 604		drm_mode_debug_printmodeline(&set->crtc->mode);
 605		drm_mode_debug_printmodeline(set->mode);
 606		mode_changed = true;
 607	}
 608
 609	/* take a reference on all unbound connectors in set, reuse the
 610	 * already taken reference for bound connectors
 611	 */
 612	for (ro = 0; ro < set->num_connectors; ro++) {
 613		if (set->connectors[ro]->encoder)
 614			continue;
 615		drm_connector_get(set->connectors[ro]);
 616	}
 617
 618	/* a) traverse passed in connector list and get encoders for them */
 619	count = 0;
 620	drm_connector_list_iter_begin(dev, &conn_iter);
 621	drm_for_each_connector_iter(connector, &conn_iter) {
 622		const struct drm_connector_helper_funcs *connector_funcs =
 623			connector->helper_private;
 624		new_encoder = connector->encoder;
 625		for (ro = 0; ro < set->num_connectors; ro++) {
 626			if (set->connectors[ro] == connector) {
 627				new_encoder = connector_funcs->best_encoder(connector);
 
 
 
 
 628				/* if we can't get an encoder for a connector
 629				   we are setting now - then fail */
 630				if (new_encoder == NULL)
 631					/* don't break so fail path works correct */
 632					fail = 1;
 633
 634				if (connector->dpms != DRM_MODE_DPMS_ON) {
 635					DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 636					mode_changed = true;
 637				}
 638
 639				break;
 640			}
 641		}
 642
 643		if (new_encoder != connector->encoder) {
 644			DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 645			mode_changed = true;
 646			/* If the encoder is reused for another connector, then
 647			 * the appropriate crtc will be set later.
 648			 */
 649			if (connector->encoder)
 650				connector->encoder->crtc = NULL;
 651			connector->encoder = new_encoder;
 652		}
 653	}
 654	drm_connector_list_iter_end(&conn_iter);
 655
 656	if (fail) {
 657		ret = -EINVAL;
 658		goto fail;
 659	}
 660
 661	count = 0;
 662	drm_connector_list_iter_begin(dev, &conn_iter);
 663	drm_for_each_connector_iter(connector, &conn_iter) {
 664		if (!connector->encoder)
 665			continue;
 666
 667		if (connector->encoder->crtc == set->crtc)
 668			new_crtc = NULL;
 669		else
 670			new_crtc = connector->encoder->crtc;
 671
 672		for (ro = 0; ro < set->num_connectors; ro++) {
 673			if (set->connectors[ro] == connector)
 674				new_crtc = set->crtc;
 675		}
 676
 677		/* Make sure the new CRTC will work with the encoder */
 678		if (new_crtc &&
 679		    !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 680			ret = -EINVAL;
 681			drm_connector_list_iter_end(&conn_iter);
 682			goto fail;
 683		}
 684		if (new_crtc != connector->encoder->crtc) {
 685			DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 686			mode_changed = true;
 687			connector->encoder->crtc = new_crtc;
 688		}
 689		if (new_crtc) {
 690			DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
 691				      connector->base.id, connector->name,
 692				      new_crtc->base.id, new_crtc->name);
 693		} else {
 694			DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 695				      connector->base.id, connector->name);
 696		}
 697	}
 698	drm_connector_list_iter_end(&conn_iter);
 699
 700	/* mode_set_base is not a required function */
 701	if (fb_changed && !crtc_funcs->mode_set_base)
 702		mode_changed = true;
 703
 704	if (mode_changed) {
 705		if (drm_helper_crtc_in_use(set->crtc)) {
 706			DRM_DEBUG_KMS("attempting to set mode from"
 707					" userspace\n");
 708			drm_mode_debug_printmodeline(set->mode);
 709			set->crtc->primary->fb = set->fb;
 710			if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 711						      set->x, set->y,
 712						      save_set.fb)) {
 713				DRM_ERROR("failed to set mode on [CRTC:%d:%s]\n",
 714					  set->crtc->base.id, set->crtc->name);
 715				set->crtc->primary->fb = save_set.fb;
 716				ret = -EINVAL;
 717				goto fail;
 718			}
 719			DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 720			for (i = 0; i < set->num_connectors; i++) {
 721				DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 722					      set->connectors[i]->name);
 723				set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 724			}
 725		}
 726		__drm_helper_disable_unused_functions(dev);
 727	} else if (fb_changed) {
 728		set->crtc->x = set->x;
 729		set->crtc->y = set->y;
 730		set->crtc->primary->fb = set->fb;
 731		ret = crtc_funcs->mode_set_base(set->crtc,
 732						set->x, set->y, save_set.fb);
 733		if (ret != 0) {
 734			set->crtc->x = save_set.x;
 735			set->crtc->y = save_set.y;
 736			set->crtc->primary->fb = save_set.fb;
 737			goto fail;
 738		}
 739	}
 740
 741	kfree(save_connector_encoders);
 742	kfree(save_encoder_crtcs);
 743	return 0;
 744
 745fail:
 746	/* Restore all previous data. */
 747	count = 0;
 748	drm_for_each_encoder(encoder, dev) {
 749		encoder->crtc = save_encoder_crtcs[count++];
 750	}
 751
 752	count = 0;
 753	drm_connector_list_iter_begin(dev, &conn_iter);
 754	drm_for_each_connector_iter(connector, &conn_iter)
 755		connector->encoder = save_connector_encoders[count++];
 756	drm_connector_list_iter_end(&conn_iter);
 757
 758	/* after fail drop reference on all unbound connectors in set, let
 759	 * bound connectors keep their reference
 760	 */
 761	for (ro = 0; ro < set->num_connectors; ro++) {
 762		if (set->connectors[ro]->encoder)
 763			continue;
 764		drm_connector_put(set->connectors[ro]);
 765	}
 766
 767	/* Try to restore the config */
 768	if (mode_changed &&
 769	    !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 770				      save_set.y, save_set.fb))
 771		DRM_ERROR("failed to restore config after modeset failure\n");
 772
 773	kfree(save_connector_encoders);
 774	kfree(save_encoder_crtcs);
 775	return ret;
 776}
 777EXPORT_SYMBOL(drm_crtc_helper_set_config);
 778
 779static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 780{
 781	int dpms = DRM_MODE_DPMS_OFF;
 782	struct drm_connector *connector;
 783	struct drm_connector_list_iter conn_iter;
 784	struct drm_device *dev = encoder->dev;
 785
 786	drm_connector_list_iter_begin(dev, &conn_iter);
 787	drm_for_each_connector_iter(connector, &conn_iter)
 788		if (connector->encoder == encoder)
 789			if (connector->dpms < dpms)
 790				dpms = connector->dpms;
 791	drm_connector_list_iter_end(&conn_iter);
 792
 793	return dpms;
 794}
 795
 796/* Helper which handles bridge ordering around encoder dpms */
 797static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 798{
 799	const struct drm_encoder_helper_funcs *encoder_funcs;
 800
 801	encoder_funcs = encoder->helper_private;
 802	if (!encoder_funcs)
 803		return;
 804
 805	if (encoder_funcs->dpms)
 806		encoder_funcs->dpms(encoder, mode);
 807}
 808
 809static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 810{
 811	int dpms = DRM_MODE_DPMS_OFF;
 812	struct drm_connector *connector;
 813	struct drm_connector_list_iter conn_iter;
 814	struct drm_device *dev = crtc->dev;
 815
 816	drm_connector_list_iter_begin(dev, &conn_iter);
 817	drm_for_each_connector_iter(connector, &conn_iter)
 818		if (connector->encoder && connector->encoder->crtc == crtc)
 819			if (connector->dpms < dpms)
 820				dpms = connector->dpms;
 821	drm_connector_list_iter_end(&conn_iter);
 822
 823	return dpms;
 824}
 825
 826/**
 827 * drm_helper_connector_dpms() - connector dpms helper implementation
 828 * @connector: affected connector
 829 * @mode: DPMS mode
 830 *
 831 * The drm_helper_connector_dpms() helper function implements the
 832 * &drm_connector_funcs.dpms callback for drivers using the legacy CRTC
 833 * helpers.
 834 *
 835 * This is the main helper function provided by the CRTC helper framework for
 836 * implementing the DPMS connector attribute. It computes the new desired DPMS
 837 * state for all encoders and CRTCs in the output mesh and calls the
 838 * &drm_crtc_helper_funcs.dpms and &drm_encoder_helper_funcs.dpms callbacks
 839 * provided by the driver.
 840 *
 841 * This function is deprecated.  New drivers must implement atomic modeset
 842 * support, where DPMS is handled in the DRM core.
 843 *
 844 * Returns:
 845 * Always returns 0.
 846 */
 847int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 848{
 849	struct drm_encoder *encoder = connector->encoder;
 850	struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 851	int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 852
 853	WARN_ON(drm_drv_uses_atomic_modeset(connector->dev));
 854
 855	if (mode == connector->dpms)
 856		return 0;
 857
 858	old_dpms = connector->dpms;
 859	connector->dpms = mode;
 860
 861	if (encoder)
 862		encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 863
 864	/* from off to on, do crtc then encoder */
 865	if (mode < old_dpms) {
 866		if (crtc) {
 867			const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 
 868			if (crtc_funcs->dpms)
 869				(*crtc_funcs->dpms) (crtc,
 870						     drm_helper_choose_crtc_dpms(crtc));
 871		}
 872		if (encoder)
 873			drm_helper_encoder_dpms(encoder, encoder_dpms);
 874	}
 875
 876	/* from on to off, do encoder then crtc */
 877	if (mode > old_dpms) {
 878		if (encoder)
 879			drm_helper_encoder_dpms(encoder, encoder_dpms);
 880		if (crtc) {
 881			const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 
 882			if (crtc_funcs->dpms)
 883				(*crtc_funcs->dpms) (crtc,
 884						     drm_helper_choose_crtc_dpms(crtc));
 885		}
 886	}
 887
 888	return 0;
 889}
 890EXPORT_SYMBOL(drm_helper_connector_dpms);
 891
 892/**
 893 * drm_helper_resume_force_mode - force-restore mode setting configuration
 894 * @dev: drm_device which should be restored
 895 *
 896 * Drivers which use the mode setting helpers can use this function to
 897 * force-restore the mode setting configuration e.g. on resume or when something
 898 * else might have trampled over the hw state (like some overzealous old BIOSen
 899 * tended to do).
 900 *
 901 * This helper doesn't provide a error return value since restoring the old
 902 * config should never fail due to resource allocation issues since the driver
 903 * has successfully set the restored configuration already. Hence this should
 904 * boil down to the equivalent of a few dpms on calls, which also don't provide
 905 * an error code.
 906 *
 907 * Drivers where simply restoring an old configuration again might fail (e.g.
 908 * due to slight differences in allocating shared resources when the
 909 * configuration is restored in a different order than when userspace set it up)
 910 * need to use their own restore logic.
 911 *
 912 * This function is deprecated. New drivers should implement atomic mode-
 913 * setting and use the atomic suspend/resume helpers.
 914 *
 915 * See also:
 916 * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 917 */
 918void drm_helper_resume_force_mode(struct drm_device *dev)
 919{
 920	struct drm_crtc *crtc;
 921	struct drm_encoder *encoder;
 922	const struct drm_crtc_helper_funcs *crtc_funcs;
 923	int encoder_dpms;
 924	bool ret;
 925
 926	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 927
 928	drm_modeset_lock_all(dev);
 929	drm_for_each_crtc(crtc, dev) {
 930
 931		if (!crtc->enabled)
 932			continue;
 933
 934		ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 935					       crtc->x, crtc->y, crtc->primary->fb);
 936
 937		/* Restoring the old config should never fail! */
 938		if (ret == false)
 939			DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 940
 941		/* Turn off outputs that were already powered off */
 942		if (drm_helper_choose_crtc_dpms(crtc)) {
 943			drm_for_each_encoder(encoder, dev) {
 944
 945				if(encoder->crtc != crtc)
 946					continue;
 947
 948				encoder_dpms = drm_helper_choose_encoder_dpms(
 949							encoder);
 950
 951				drm_helper_encoder_dpms(encoder, encoder_dpms);
 952			}
 953
 954			crtc_funcs = crtc->helper_private;
 955			if (crtc_funcs->dpms)
 956				(*crtc_funcs->dpms) (crtc,
 957						     drm_helper_choose_crtc_dpms(crtc));
 958		}
 959	}
 960
 961	/* disable the unused connectors while restoring the modesetting */
 962	__drm_helper_disable_unused_functions(dev);
 963	drm_modeset_unlock_all(dev);
 964}
 965EXPORT_SYMBOL(drm_helper_resume_force_mode);
 966
 967/**
 968 * drm_helper_force_disable_all - Forcibly turn off all enabled CRTCs
 969 * @dev: DRM device whose CRTCs to turn off
 970 *
 971 * Drivers may want to call this on unload to ensure that all displays are
 972 * unlit and the GPU is in a consistent, low power state. Takes modeset locks.
 973 *
 974 * Note: This should only be used by non-atomic legacy drivers. For an atomic
 975 * version look at drm_atomic_helper_shutdown().
 976 *
 977 * Returns:
 978 * Zero on success, error code on failure.
 979 */
 980int drm_helper_force_disable_all(struct drm_device *dev)
 981{
 982	struct drm_crtc *crtc;
 983	int ret = 0;
 984
 985	drm_modeset_lock_all(dev);
 986	drm_for_each_crtc(crtc, dev)
 987		if (crtc->enabled) {
 988			struct drm_mode_set set = {
 989				.crtc = crtc,
 990			};
 991
 992			ret = drm_mode_set_config_internal(&set);
 993			if (ret)
 994				goto out;
 995		}
 996out:
 997	drm_modeset_unlock_all(dev);
 998	return ret;
 999}
1000EXPORT_SYMBOL(drm_helper_force_disable_all);
v6.9.4
   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/kernel.h>
  34#include <linux/moduleparam.h>
  35#include <linux/dynamic_debug.h>
  36
  37#include <drm/drm_atomic.h>
  38#include <drm/drm_atomic_helper.h>
  39#include <drm/drm_atomic_uapi.h>
  40#include <drm/drm_bridge.h>
  41#include <drm/drm_crtc.h>
  42#include <drm/drm_crtc_helper.h>
  43#include <drm/drm_drv.h>
  44#include <drm/drm_edid.h>
  45#include <drm/drm_encoder.h>
 
  46#include <drm/drm_fourcc.h>
  47#include <drm/drm_framebuffer.h>
  48#include <drm/drm_print.h>
  49#include <drm/drm_vblank.h>
  50
  51#include "drm_crtc_helper_internal.h"
  52
  53DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
  54			"DRM_UT_CORE",
  55			"DRM_UT_DRIVER",
  56			"DRM_UT_KMS",
  57			"DRM_UT_PRIME",
  58			"DRM_UT_ATOMIC",
  59			"DRM_UT_VBL",
  60			"DRM_UT_STATE",
  61			"DRM_UT_LEASE",
  62			"DRM_UT_DP",
  63			"DRM_UT_DRMRES");
  64
  65/**
  66 * DOC: overview
  67 *
  68 * The CRTC modeset helper library provides a default set_config implementation
  69 * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
  70 * the same callbacks which drivers can use to e.g. restore the modeset
  71 * configuration on resume with drm_helper_resume_force_mode().
  72 *
  73 * Note that this helper library doesn't track the current power state of CRTCs
  74 * and encoders. It can call callbacks like &drm_encoder_helper_funcs.dpms even
  75 * though the hardware is already in the desired state. This deficiency has been
  76 * fixed in the atomic helpers.
  77 *
  78 * The driver callbacks are mostly compatible with the atomic modeset helpers,
  79 * except for the handling of the primary plane: Atomic helpers require that the
  80 * primary plane is implemented as a real standalone plane and not directly tied
  81 * to the CRTC state. For easier transition this library provides functions to
  82 * implement the old semantics required by the CRTC helpers using the new plane
  83 * and atomic helper callbacks.
  84 *
  85 * Drivers are strongly urged to convert to the atomic helpers (by way of first
  86 * converting to the plane helpers). New drivers must not use these functions
  87 * but need to implement the atomic interface instead, potentially using the
  88 * atomic helpers for that.
  89 *
  90 * These legacy modeset helpers use the same function table structures as
  91 * all other modesetting helpers. See the documentation for struct
  92 * &drm_crtc_helper_funcs, &struct drm_encoder_helper_funcs and struct
  93 * &drm_connector_helper_funcs.
  94 */
  95
  96/**
  97 * drm_helper_encoder_in_use - check if a given encoder is in use
  98 * @encoder: encoder to check
  99 *
 100 * Checks whether @encoder is with the current mode setting output configuration
 101 * in use by any connector. This doesn't mean that it is actually enabled since
 102 * the DPMS state is tracked separately.
 103 *
 104 * Returns:
 105 * True if @encoder is used, false otherwise.
 106 */
 107bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
 108{
 109	struct drm_connector *connector;
 110	struct drm_connector_list_iter conn_iter;
 111	struct drm_device *dev = encoder->dev;
 112
 113	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 114
 115	/*
 116	 * We can expect this mutex to be locked if we are not panicking.
 117	 * Locking is currently fubar in the panic handler.
 118	 */
 119	if (!oops_in_progress) {
 120		WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 121		WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 122	}
 123
 124
 125	drm_connector_list_iter_begin(dev, &conn_iter);
 126	drm_for_each_connector_iter(connector, &conn_iter) {
 127		if (connector->encoder == encoder) {
 128			drm_connector_list_iter_end(&conn_iter);
 129			return true;
 130		}
 131	}
 132	drm_connector_list_iter_end(&conn_iter);
 133	return false;
 134}
 135EXPORT_SYMBOL(drm_helper_encoder_in_use);
 136
 137/**
 138 * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 139 * @crtc: CRTC to check
 140 *
 141 * Checks whether @crtc is with the current mode setting output configuration
 142 * in use by any connector. This doesn't mean that it is actually enabled since
 143 * the DPMS state is tracked separately.
 144 *
 145 * Returns:
 146 * True if @crtc is used, false otherwise.
 147 */
 148bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 149{
 150	struct drm_encoder *encoder;
 151	struct drm_device *dev = crtc->dev;
 152
 153	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 154
 155	/*
 156	 * We can expect this mutex to be locked if we are not panicking.
 157	 * Locking is currently fubar in the panic handler.
 158	 */
 159	if (!oops_in_progress)
 160		WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 161
 162	drm_for_each_encoder(encoder, dev)
 163		if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 164			return true;
 165	return false;
 166}
 167EXPORT_SYMBOL(drm_helper_crtc_in_use);
 168
 169static void
 170drm_encoder_disable(struct drm_encoder *encoder)
 171{
 172	const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 173
 174	if (!encoder_funcs)
 175		return;
 176
 177	if (encoder_funcs->disable)
 178		(*encoder_funcs->disable)(encoder);
 179	else if (encoder_funcs->dpms)
 180		(*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 181}
 182
 183static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 184{
 185	struct drm_encoder *encoder;
 186	struct drm_crtc *crtc;
 187
 188	drm_warn_on_modeset_not_all_locked(dev);
 189
 190	drm_for_each_encoder(encoder, dev) {
 191		if (!drm_helper_encoder_in_use(encoder)) {
 192			drm_encoder_disable(encoder);
 193			/* disconnect encoder from any connector */
 194			encoder->crtc = NULL;
 195		}
 196	}
 197
 198	drm_for_each_crtc(crtc, dev) {
 199		const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 200
 201		crtc->enabled = drm_helper_crtc_in_use(crtc);
 202		if (!crtc->enabled) {
 203			if (crtc_funcs->disable)
 204				(*crtc_funcs->disable)(crtc);
 205			else
 206				(*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 207			crtc->primary->fb = NULL;
 208		}
 209	}
 210}
 211
 212/**
 213 * drm_helper_disable_unused_functions - disable unused objects
 214 * @dev: DRM device
 215 *
 216 * This function walks through the entire mode setting configuration of @dev. It
 217 * will remove any CRTC links of unused encoders and encoder links of
 218 * disconnected connectors. Then it will disable all unused encoders and CRTCs
 219 * either by calling their disable callback if available or by calling their
 220 * dpms callback with DRM_MODE_DPMS_OFF.
 221 *
 222 * NOTE:
 223 *
 224 * This function is part of the legacy modeset helper library and will cause
 225 * major confusion with atomic drivers. This is because atomic helpers guarantee
 226 * to never call ->disable() hooks on a disabled function, or ->enable() hooks
 227 * on an enabled functions. drm_helper_disable_unused_functions() on the other
 228 * hand throws such guarantees into the wind and calls disable hooks
 229 * unconditionally on unused functions.
 230 */
 231void drm_helper_disable_unused_functions(struct drm_device *dev)
 232{
 233	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 234
 235	drm_modeset_lock_all(dev);
 236	__drm_helper_disable_unused_functions(dev);
 237	drm_modeset_unlock_all(dev);
 238}
 239EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 240
 241/*
 242 * Check the CRTC we're going to map each output to vs. its current
 243 * CRTC.  If they don't match, we have to disable the output and the CRTC
 244 * since the driver will have to re-route things.
 245 */
 246static void
 247drm_crtc_prepare_encoders(struct drm_device *dev)
 248{
 249	const struct drm_encoder_helper_funcs *encoder_funcs;
 250	struct drm_encoder *encoder;
 251
 252	drm_for_each_encoder(encoder, dev) {
 253		encoder_funcs = encoder->helper_private;
 254		if (!encoder_funcs)
 255			continue;
 256
 257		/* Disable unused encoders */
 258		if (encoder->crtc == NULL)
 259			drm_encoder_disable(encoder);
 
 
 
 
 260	}
 261}
 262
 263/**
 264 * drm_crtc_helper_set_mode - internal helper to set a mode
 265 * @crtc: CRTC to program
 266 * @mode: mode to use
 267 * @x: horizontal offset into the surface
 268 * @y: vertical offset into the surface
 269 * @old_fb: old framebuffer, for cleanup
 270 *
 271 * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 272 * to fixup or reject the mode prior to trying to set it. This is an internal
 273 * helper that drivers could e.g. use to update properties that require the
 274 * entire output pipe to be disabled and re-enabled in a new configuration. For
 275 * example for changing whether audio is enabled on a hdmi link or for changing
 276 * panel fitter or dither attributes. It is also called by the
 277 * drm_crtc_helper_set_config() helper function to drive the mode setting
 278 * sequence.
 279 *
 280 * Returns:
 281 * True if the mode was set successfully, false otherwise.
 282 */
 283bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 284			      struct drm_display_mode *mode,
 285			      int x, int y,
 286			      struct drm_framebuffer *old_fb)
 287{
 288	struct drm_device *dev = crtc->dev;
 289	struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
 290	const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 291	const struct drm_encoder_helper_funcs *encoder_funcs;
 292	int saved_x, saved_y;
 293	bool saved_enabled;
 294	struct drm_encoder *encoder;
 295	bool ret = true;
 296
 297	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 298
 299	drm_warn_on_modeset_not_all_locked(dev);
 300
 301	saved_enabled = crtc->enabled;
 302	crtc->enabled = drm_helper_crtc_in_use(crtc);
 303	if (!crtc->enabled)
 304		return true;
 305
 306	adjusted_mode = drm_mode_duplicate(dev, mode);
 307	if (!adjusted_mode) {
 308		crtc->enabled = saved_enabled;
 309		return false;
 310	}
 311
 312	drm_mode_init(&saved_mode, &crtc->mode);
 313	drm_mode_init(&saved_hwmode, &crtc->hwmode);
 314	saved_x = crtc->x;
 315	saved_y = crtc->y;
 316
 317	/* Update crtc values up front so the driver can rely on them for mode
 318	 * setting.
 319	 */
 320	drm_mode_copy(&crtc->mode, mode);
 321	crtc->x = x;
 322	crtc->y = y;
 323
 324	/* Pass our mode to the connectors and the CRTC to give them a chance to
 325	 * adjust it according to limitations or connector properties, and also
 326	 * a chance to reject the mode entirely.
 327	 */
 328	drm_for_each_encoder(encoder, dev) {
 329
 330		if (encoder->crtc != crtc)
 331			continue;
 332
 333		encoder_funcs = encoder->helper_private;
 334		if (!encoder_funcs)
 335			continue;
 336
 337		encoder_funcs = encoder->helper_private;
 338		if (encoder_funcs->mode_fixup) {
 339			if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 340							      adjusted_mode))) {
 341				DRM_DEBUG_KMS("Encoder fixup failed\n");
 342				goto done;
 343			}
 344		}
 345	}
 346
 347	if (crtc_funcs->mode_fixup) {
 348		if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
 349						adjusted_mode))) {
 350			DRM_DEBUG_KMS("CRTC fixup failed\n");
 351			goto done;
 352		}
 353	}
 354	DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
 355
 356	drm_mode_copy(&crtc->hwmode, adjusted_mode);
 357
 358	/* Prepare the encoders and CRTCs before setting the mode. */
 359	drm_for_each_encoder(encoder, dev) {
 360
 361		if (encoder->crtc != crtc)
 362			continue;
 363
 364		encoder_funcs = encoder->helper_private;
 365		if (!encoder_funcs)
 366			continue;
 367
 368		/* Disable the encoders as the first thing we do. */
 369		if (encoder_funcs->prepare)
 370			encoder_funcs->prepare(encoder);
 371	}
 372
 373	drm_crtc_prepare_encoders(dev);
 374
 375	crtc_funcs->prepare(crtc);
 376
 377	/* Set up the DPLL and any encoders state that needs to adjust or depend
 378	 * on the DPLL.
 379	 */
 380	ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 381	if (!ret)
 382	    goto done;
 383
 384	drm_for_each_encoder(encoder, dev) {
 385
 386		if (encoder->crtc != crtc)
 387			continue;
 388
 389		encoder_funcs = encoder->helper_private;
 390		if (!encoder_funcs)
 391			continue;
 392
 393		DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%s]\n",
 394			encoder->base.id, encoder->name, mode->name);
 395		if (encoder_funcs->mode_set)
 396			encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 397	}
 398
 399	/* Now enable the clocks, plane, pipe, and connectors that we set up. */
 400	crtc_funcs->commit(crtc);
 401
 402	drm_for_each_encoder(encoder, dev) {
 403
 404		if (encoder->crtc != crtc)
 405			continue;
 406
 407		encoder_funcs = encoder->helper_private;
 408		if (!encoder_funcs)
 409			continue;
 410
 411		if (encoder_funcs->commit)
 412			encoder_funcs->commit(encoder);
 413	}
 414
 415	/* Calculate and store various constants which
 416	 * are later needed by vblank and swap-completion
 417	 * timestamping. They are derived from true hwmode.
 418	 */
 419	drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 420
 421	/* FIXME: add subpixel order */
 422done:
 423	drm_mode_destroy(dev, adjusted_mode);
 424	if (!ret) {
 425		crtc->enabled = saved_enabled;
 426		drm_mode_copy(&crtc->mode, &saved_mode);
 427		drm_mode_copy(&crtc->hwmode, &saved_hwmode);
 428		crtc->x = saved_x;
 429		crtc->y = saved_y;
 430	}
 431
 432	return ret;
 433}
 434EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 435
 436/**
 437 * drm_crtc_helper_atomic_check() - Helper to check CRTC atomic-state
 438 * @crtc: CRTC to check
 439 * @state: atomic state object
 440 *
 441 * Provides a default CRTC-state check handler for CRTCs that only have
 442 * one primary plane attached to it. This is often the case for the CRTC
 443 * of simple framebuffers.
 444 *
 445 * RETURNS:
 446 * Zero on success, or an errno code otherwise.
 447 */
 448int drm_crtc_helper_atomic_check(struct drm_crtc *crtc, struct drm_atomic_state *state)
 449{
 450	struct drm_crtc_state *new_crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
 451
 452	if (!new_crtc_state->enable)
 453		return 0;
 454
 455	return drm_atomic_helper_check_crtc_primary_plane(new_crtc_state);
 456}
 457EXPORT_SYMBOL(drm_crtc_helper_atomic_check);
 458
 459static void
 460drm_crtc_helper_disable(struct drm_crtc *crtc)
 461{
 462	struct drm_device *dev = crtc->dev;
 463	struct drm_connector *connector;
 464	struct drm_encoder *encoder;
 465
 466	/* Decouple all encoders and their attached connectors from this crtc */
 467	drm_for_each_encoder(encoder, dev) {
 468		struct drm_connector_list_iter conn_iter;
 469
 470		if (encoder->crtc != crtc)
 471			continue;
 472
 473		drm_connector_list_iter_begin(dev, &conn_iter);
 474		drm_for_each_connector_iter(connector, &conn_iter) {
 475			if (connector->encoder != encoder)
 476				continue;
 477
 478			connector->encoder = NULL;
 479
 480			/*
 481			 * drm_helper_disable_unused_functions() ought to be
 482			 * doing this, but since we've decoupled the encoder
 483			 * from the connector above, the required connection
 484			 * between them is henceforth no longer available.
 485			 */
 486			connector->dpms = DRM_MODE_DPMS_OFF;
 487
 488			/* we keep a reference while the encoder is bound */
 489			drm_connector_put(connector);
 490		}
 491		drm_connector_list_iter_end(&conn_iter);
 492	}
 493
 494	__drm_helper_disable_unused_functions(dev);
 495}
 496
 497/*
 498 * For connectors that support multiple encoders, either the
 499 * .atomic_best_encoder() or .best_encoder() operation must be implemented.
 500 */
 501struct drm_encoder *
 502drm_connector_get_single_encoder(struct drm_connector *connector)
 503{
 504	struct drm_encoder *encoder;
 505
 506	WARN_ON(hweight32(connector->possible_encoders) > 1);
 507	drm_connector_for_each_possible_encoder(connector, encoder)
 508		return encoder;
 509
 510	return NULL;
 511}
 512
 513/**
 514 * drm_crtc_helper_set_config - set a new config from userspace
 515 * @set: mode set configuration
 516 * @ctx: lock acquire context, not used here
 517 *
 518 * The drm_crtc_helper_set_config() helper function implements the of
 519 * &drm_crtc_funcs.set_config callback for drivers using the legacy CRTC
 520 * helpers.
 521 *
 522 * It first tries to locate the best encoder for each connector by calling the
 523 * connector @drm_connector_helper_funcs.best_encoder helper operation.
 524 *
 525 * After locating the appropriate encoders, the helper function will call the
 526 * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
 527 * or reject it completely in which case an error will be returned to the
 528 * application. If the new configuration after mode adjustment is identical to
 529 * the current configuration the helper function will return without performing
 530 * any other operation.
 531 *
 532 * If the adjusted mode is identical to the current mode but changes to the
 533 * frame buffer need to be applied, the drm_crtc_helper_set_config() function
 534 * will call the CRTC &drm_crtc_helper_funcs.mode_set_base helper operation.
 535 *
 536 * If the adjusted mode differs from the current mode, or if the
 537 * ->mode_set_base() helper operation is not provided, the helper function
 538 * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
 539 * and ->commit() CRTC and encoder helper operations, in that order.
 540 * Alternatively it can also use the dpms and disable helper operations. For
 541 * details see &struct drm_crtc_helper_funcs and struct
 542 * &drm_encoder_helper_funcs.
 543 *
 544 * This function is deprecated.  New drivers must implement atomic modeset
 545 * support, for which this function is unsuitable. Instead drivers should use
 546 * drm_atomic_helper_set_config().
 547 *
 548 * Returns:
 549 * Returns 0 on success, negative errno numbers on failure.
 550 */
 551int drm_crtc_helper_set_config(struct drm_mode_set *set,
 552			       struct drm_modeset_acquire_ctx *ctx)
 553{
 554	struct drm_device *dev;
 555	struct drm_crtc **save_encoder_crtcs, *new_crtc;
 556	struct drm_encoder **save_connector_encoders, *new_encoder, *encoder;
 557	bool mode_changed = false; /* if true do a full mode set */
 558	bool fb_changed = false; /* if true and !mode_changed just do a flip */
 559	struct drm_connector *connector;
 560	struct drm_connector_list_iter conn_iter;
 561	int count = 0, ro, fail = 0;
 562	const struct drm_crtc_helper_funcs *crtc_funcs;
 563	struct drm_mode_set save_set;
 564	int ret;
 565	int i;
 566
 567	DRM_DEBUG_KMS("\n");
 568
 569	BUG_ON(!set);
 570	BUG_ON(!set->crtc);
 571	BUG_ON(!set->crtc->helper_private);
 572
 573	/* Enforce sane interface api - has been abused by the fb helper. */
 574	BUG_ON(!set->mode && set->fb);
 575	BUG_ON(set->fb && set->num_connectors == 0);
 576
 577	crtc_funcs = set->crtc->helper_private;
 578
 579	dev = set->crtc->dev;
 580	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 581
 582	if (!set->mode)
 583		set->fb = NULL;
 584
 585	if (set->fb) {
 586		DRM_DEBUG_KMS("[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 587			      set->crtc->base.id, set->crtc->name,
 588			      set->fb->base.id,
 589			      (int)set->num_connectors, set->x, set->y);
 590	} else {
 591		DRM_DEBUG_KMS("[CRTC:%d:%s] [NOFB]\n",
 592			      set->crtc->base.id, set->crtc->name);
 593		drm_crtc_helper_disable(set->crtc);
 594		return 0;
 595	}
 596
 597	drm_warn_on_modeset_not_all_locked(dev);
 598
 599	/*
 600	 * Allocate space for the backup of all (non-pointer) encoder and
 601	 * connector data.
 602	 */
 603	save_encoder_crtcs = kcalloc(dev->mode_config.num_encoder,
 604				sizeof(struct drm_crtc *), GFP_KERNEL);
 605	if (!save_encoder_crtcs)
 606		return -ENOMEM;
 607
 608	save_connector_encoders = kcalloc(dev->mode_config.num_connector,
 609				sizeof(struct drm_encoder *), GFP_KERNEL);
 610	if (!save_connector_encoders) {
 611		kfree(save_encoder_crtcs);
 612		return -ENOMEM;
 613	}
 614
 615	/*
 616	 * Copy data. Note that driver private data is not affected.
 617	 * Should anything bad happen only the expected state is
 618	 * restored, not the drivers personal bookkeeping.
 619	 */
 620	count = 0;
 621	drm_for_each_encoder(encoder, dev) {
 622		save_encoder_crtcs[count++] = encoder->crtc;
 623	}
 624
 625	count = 0;
 626	drm_connector_list_iter_begin(dev, &conn_iter);
 627	drm_for_each_connector_iter(connector, &conn_iter)
 628		save_connector_encoders[count++] = connector->encoder;
 629	drm_connector_list_iter_end(&conn_iter);
 630
 631	save_set.crtc = set->crtc;
 632	save_set.mode = &set->crtc->mode;
 633	save_set.x = set->crtc->x;
 634	save_set.y = set->crtc->y;
 635	save_set.fb = set->crtc->primary->fb;
 636
 637	/* We should be able to check here if the fb has the same properties
 638	 * and then just flip_or_move it */
 639	if (set->crtc->primary->fb != set->fb) {
 640		/* If we have no fb then treat it as a full mode set */
 641		if (set->crtc->primary->fb == NULL) {
 642			DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 643			mode_changed = true;
 644		} else if (set->fb->format != set->crtc->primary->fb->format) {
 645			mode_changed = true;
 646		} else
 647			fb_changed = true;
 648	}
 649
 650	if (set->x != set->crtc->x || set->y != set->crtc->y)
 651		fb_changed = true;
 652
 653	if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
 654		DRM_DEBUG_KMS("modes are different, full mode set\n");
 655		drm_mode_debug_printmodeline(&set->crtc->mode);
 656		drm_mode_debug_printmodeline(set->mode);
 657		mode_changed = true;
 658	}
 659
 660	/* take a reference on all unbound connectors in set, reuse the
 661	 * already taken reference for bound connectors
 662	 */
 663	for (ro = 0; ro < set->num_connectors; ro++) {
 664		if (set->connectors[ro]->encoder)
 665			continue;
 666		drm_connector_get(set->connectors[ro]);
 667	}
 668
 669	/* a) traverse passed in connector list and get encoders for them */
 670	count = 0;
 671	drm_connector_list_iter_begin(dev, &conn_iter);
 672	drm_for_each_connector_iter(connector, &conn_iter) {
 673		const struct drm_connector_helper_funcs *connector_funcs =
 674			connector->helper_private;
 675		new_encoder = connector->encoder;
 676		for (ro = 0; ro < set->num_connectors; ro++) {
 677			if (set->connectors[ro] == connector) {
 678				if (connector_funcs->best_encoder)
 679					new_encoder = connector_funcs->best_encoder(connector);
 680				else
 681					new_encoder = drm_connector_get_single_encoder(connector);
 682
 683				/* if we can't get an encoder for a connector
 684				   we are setting now - then fail */
 685				if (new_encoder == NULL)
 686					/* don't break so fail path works correct */
 687					fail = 1;
 688
 689				if (connector->dpms != DRM_MODE_DPMS_ON) {
 690					DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 691					mode_changed = true;
 692				}
 693
 694				break;
 695			}
 696		}
 697
 698		if (new_encoder != connector->encoder) {
 699			DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 700			mode_changed = true;
 701			/* If the encoder is reused for another connector, then
 702			 * the appropriate crtc will be set later.
 703			 */
 704			if (connector->encoder)
 705				connector->encoder->crtc = NULL;
 706			connector->encoder = new_encoder;
 707		}
 708	}
 709	drm_connector_list_iter_end(&conn_iter);
 710
 711	if (fail) {
 712		ret = -EINVAL;
 713		goto fail;
 714	}
 715
 716	count = 0;
 717	drm_connector_list_iter_begin(dev, &conn_iter);
 718	drm_for_each_connector_iter(connector, &conn_iter) {
 719		if (!connector->encoder)
 720			continue;
 721
 722		if (connector->encoder->crtc == set->crtc)
 723			new_crtc = NULL;
 724		else
 725			new_crtc = connector->encoder->crtc;
 726
 727		for (ro = 0; ro < set->num_connectors; ro++) {
 728			if (set->connectors[ro] == connector)
 729				new_crtc = set->crtc;
 730		}
 731
 732		/* Make sure the new CRTC will work with the encoder */
 733		if (new_crtc &&
 734		    !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 735			ret = -EINVAL;
 736			drm_connector_list_iter_end(&conn_iter);
 737			goto fail;
 738		}
 739		if (new_crtc != connector->encoder->crtc) {
 740			DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 741			mode_changed = true;
 742			connector->encoder->crtc = new_crtc;
 743		}
 744		if (new_crtc) {
 745			DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
 746				      connector->base.id, connector->name,
 747				      new_crtc->base.id, new_crtc->name);
 748		} else {
 749			DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 750				      connector->base.id, connector->name);
 751		}
 752	}
 753	drm_connector_list_iter_end(&conn_iter);
 754
 755	/* mode_set_base is not a required function */
 756	if (fb_changed && !crtc_funcs->mode_set_base)
 757		mode_changed = true;
 758
 759	if (mode_changed) {
 760		if (drm_helper_crtc_in_use(set->crtc)) {
 761			DRM_DEBUG_KMS("attempting to set mode from"
 762					" userspace\n");
 763			drm_mode_debug_printmodeline(set->mode);
 764			set->crtc->primary->fb = set->fb;
 765			if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 766						      set->x, set->y,
 767						      save_set.fb)) {
 768				DRM_ERROR("failed to set mode on [CRTC:%d:%s]\n",
 769					  set->crtc->base.id, set->crtc->name);
 770				set->crtc->primary->fb = save_set.fb;
 771				ret = -EINVAL;
 772				goto fail;
 773			}
 774			DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 775			for (i = 0; i < set->num_connectors; i++) {
 776				DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 777					      set->connectors[i]->name);
 778				set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 779			}
 780		}
 781		__drm_helper_disable_unused_functions(dev);
 782	} else if (fb_changed) {
 783		set->crtc->x = set->x;
 784		set->crtc->y = set->y;
 785		set->crtc->primary->fb = set->fb;
 786		ret = crtc_funcs->mode_set_base(set->crtc,
 787						set->x, set->y, save_set.fb);
 788		if (ret != 0) {
 789			set->crtc->x = save_set.x;
 790			set->crtc->y = save_set.y;
 791			set->crtc->primary->fb = save_set.fb;
 792			goto fail;
 793		}
 794	}
 795
 796	kfree(save_connector_encoders);
 797	kfree(save_encoder_crtcs);
 798	return 0;
 799
 800fail:
 801	/* Restore all previous data. */
 802	count = 0;
 803	drm_for_each_encoder(encoder, dev) {
 804		encoder->crtc = save_encoder_crtcs[count++];
 805	}
 806
 807	count = 0;
 808	drm_connector_list_iter_begin(dev, &conn_iter);
 809	drm_for_each_connector_iter(connector, &conn_iter)
 810		connector->encoder = save_connector_encoders[count++];
 811	drm_connector_list_iter_end(&conn_iter);
 812
 813	/* after fail drop reference on all unbound connectors in set, let
 814	 * bound connectors keep their reference
 815	 */
 816	for (ro = 0; ro < set->num_connectors; ro++) {
 817		if (set->connectors[ro]->encoder)
 818			continue;
 819		drm_connector_put(set->connectors[ro]);
 820	}
 821
 822	/* Try to restore the config */
 823	if (mode_changed &&
 824	    !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 825				      save_set.y, save_set.fb))
 826		DRM_ERROR("failed to restore config after modeset failure\n");
 827
 828	kfree(save_connector_encoders);
 829	kfree(save_encoder_crtcs);
 830	return ret;
 831}
 832EXPORT_SYMBOL(drm_crtc_helper_set_config);
 833
 834static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 835{
 836	int dpms = DRM_MODE_DPMS_OFF;
 837	struct drm_connector *connector;
 838	struct drm_connector_list_iter conn_iter;
 839	struct drm_device *dev = encoder->dev;
 840
 841	drm_connector_list_iter_begin(dev, &conn_iter);
 842	drm_for_each_connector_iter(connector, &conn_iter)
 843		if (connector->encoder == encoder)
 844			if (connector->dpms < dpms)
 845				dpms = connector->dpms;
 846	drm_connector_list_iter_end(&conn_iter);
 847
 848	return dpms;
 849}
 850
 851/* Helper which handles bridge ordering around encoder dpms */
 852static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 853{
 854	const struct drm_encoder_helper_funcs *encoder_funcs;
 855
 856	encoder_funcs = encoder->helper_private;
 857	if (!encoder_funcs)
 858		return;
 859
 860	if (encoder_funcs->dpms)
 861		encoder_funcs->dpms(encoder, mode);
 862}
 863
 864static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 865{
 866	int dpms = DRM_MODE_DPMS_OFF;
 867	struct drm_connector *connector;
 868	struct drm_connector_list_iter conn_iter;
 869	struct drm_device *dev = crtc->dev;
 870
 871	drm_connector_list_iter_begin(dev, &conn_iter);
 872	drm_for_each_connector_iter(connector, &conn_iter)
 873		if (connector->encoder && connector->encoder->crtc == crtc)
 874			if (connector->dpms < dpms)
 875				dpms = connector->dpms;
 876	drm_connector_list_iter_end(&conn_iter);
 877
 878	return dpms;
 879}
 880
 881/**
 882 * drm_helper_connector_dpms() - connector dpms helper implementation
 883 * @connector: affected connector
 884 * @mode: DPMS mode
 885 *
 886 * The drm_helper_connector_dpms() helper function implements the
 887 * &drm_connector_funcs.dpms callback for drivers using the legacy CRTC
 888 * helpers.
 889 *
 890 * This is the main helper function provided by the CRTC helper framework for
 891 * implementing the DPMS connector attribute. It computes the new desired DPMS
 892 * state for all encoders and CRTCs in the output mesh and calls the
 893 * &drm_crtc_helper_funcs.dpms and &drm_encoder_helper_funcs.dpms callbacks
 894 * provided by the driver.
 895 *
 896 * This function is deprecated.  New drivers must implement atomic modeset
 897 * support, where DPMS is handled in the DRM core.
 898 *
 899 * Returns:
 900 * Always returns 0.
 901 */
 902int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 903{
 904	struct drm_encoder *encoder = connector->encoder;
 905	struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 906	int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 907
 908	WARN_ON(drm_drv_uses_atomic_modeset(connector->dev));
 909
 910	if (mode == connector->dpms)
 911		return 0;
 912
 913	old_dpms = connector->dpms;
 914	connector->dpms = mode;
 915
 916	if (encoder)
 917		encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 918
 919	/* from off to on, do crtc then encoder */
 920	if (mode < old_dpms) {
 921		if (crtc) {
 922			const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 923
 924			if (crtc_funcs->dpms)
 925				(*crtc_funcs->dpms) (crtc,
 926						     drm_helper_choose_crtc_dpms(crtc));
 927		}
 928		if (encoder)
 929			drm_helper_encoder_dpms(encoder, encoder_dpms);
 930	}
 931
 932	/* from on to off, do encoder then crtc */
 933	if (mode > old_dpms) {
 934		if (encoder)
 935			drm_helper_encoder_dpms(encoder, encoder_dpms);
 936		if (crtc) {
 937			const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 938
 939			if (crtc_funcs->dpms)
 940				(*crtc_funcs->dpms) (crtc,
 941						     drm_helper_choose_crtc_dpms(crtc));
 942		}
 943	}
 944
 945	return 0;
 946}
 947EXPORT_SYMBOL(drm_helper_connector_dpms);
 948
 949/**
 950 * drm_helper_resume_force_mode - force-restore mode setting configuration
 951 * @dev: drm_device which should be restored
 952 *
 953 * Drivers which use the mode setting helpers can use this function to
 954 * force-restore the mode setting configuration e.g. on resume or when something
 955 * else might have trampled over the hw state (like some overzealous old BIOSen
 956 * tended to do).
 957 *
 958 * This helper doesn't provide a error return value since restoring the old
 959 * config should never fail due to resource allocation issues since the driver
 960 * has successfully set the restored configuration already. Hence this should
 961 * boil down to the equivalent of a few dpms on calls, which also don't provide
 962 * an error code.
 963 *
 964 * Drivers where simply restoring an old configuration again might fail (e.g.
 965 * due to slight differences in allocating shared resources when the
 966 * configuration is restored in a different order than when userspace set it up)
 967 * need to use their own restore logic.
 968 *
 969 * This function is deprecated. New drivers should implement atomic mode-
 970 * setting and use the atomic suspend/resume helpers.
 971 *
 972 * See also:
 973 * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 974 */
 975void drm_helper_resume_force_mode(struct drm_device *dev)
 976{
 977	struct drm_crtc *crtc;
 978	struct drm_encoder *encoder;
 979	const struct drm_crtc_helper_funcs *crtc_funcs;
 980	int encoder_dpms;
 981	bool ret;
 982
 983	WARN_ON(drm_drv_uses_atomic_modeset(dev));
 984
 985	drm_modeset_lock_all(dev);
 986	drm_for_each_crtc(crtc, dev) {
 987
 988		if (!crtc->enabled)
 989			continue;
 990
 991		ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 992					       crtc->x, crtc->y, crtc->primary->fb);
 993
 994		/* Restoring the old config should never fail! */
 995		if (ret == false)
 996			DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 997
 998		/* Turn off outputs that were already powered off */
 999		if (drm_helper_choose_crtc_dpms(crtc)) {
1000			drm_for_each_encoder(encoder, dev) {
1001
1002				if(encoder->crtc != crtc)
1003					continue;
1004
1005				encoder_dpms = drm_helper_choose_encoder_dpms(
1006							encoder);
1007
1008				drm_helper_encoder_dpms(encoder, encoder_dpms);
1009			}
1010
1011			crtc_funcs = crtc->helper_private;
1012			if (crtc_funcs->dpms)
1013				(*crtc_funcs->dpms) (crtc,
1014						     drm_helper_choose_crtc_dpms(crtc));
1015		}
1016	}
1017
1018	/* disable the unused connectors while restoring the modesetting */
1019	__drm_helper_disable_unused_functions(dev);
1020	drm_modeset_unlock_all(dev);
1021}
1022EXPORT_SYMBOL(drm_helper_resume_force_mode);
1023
1024/**
1025 * drm_helper_force_disable_all - Forcibly turn off all enabled CRTCs
1026 * @dev: DRM device whose CRTCs to turn off
1027 *
1028 * Drivers may want to call this on unload to ensure that all displays are
1029 * unlit and the GPU is in a consistent, low power state. Takes modeset locks.
1030 *
1031 * Note: This should only be used by non-atomic legacy drivers. For an atomic
1032 * version look at drm_atomic_helper_shutdown().
1033 *
1034 * Returns:
1035 * Zero on success, error code on failure.
1036 */
1037int drm_helper_force_disable_all(struct drm_device *dev)
1038{
1039	struct drm_crtc *crtc;
1040	int ret = 0;
1041
1042	drm_modeset_lock_all(dev);
1043	drm_for_each_crtc(crtc, dev)
1044		if (crtc->enabled) {
1045			struct drm_mode_set set = {
1046				.crtc = crtc,
1047			};
1048
1049			ret = drm_mode_set_config_internal(&set);
1050			if (ret)
1051				goto out;
1052		}
1053out:
1054	drm_modeset_unlock_all(dev);
1055	return ret;
1056}
1057EXPORT_SYMBOL(drm_helper_force_disable_all);