1/*
   2 * Copyright (C) 2014 Red Hat
   3 * Copyright (C) 2014 Intel Corp.
   4 *
   5 * Permission is hereby granted, free of charge, to any person obtaining a
   6 * copy of this software and associated documentation files (the "Software"),
   7 * to deal in the Software without restriction, including without limitation
   8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9 * and/or sell copies of the Software, and to permit persons to whom the
  10 * Software is furnished to do so, subject to the following conditions:
  11 *
  12 * The above copyright notice and this permission notice shall be included in
  13 * all copies or substantial portions of the Software.
  14 *
  15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  21 * OTHER DEALINGS IN THE SOFTWARE.
  22 *
  23 * Authors:
  24 * Rob Clark <robdclark@gmail.com>
  25 * Daniel Vetter <daniel.vetter@ffwll.ch>
  26 */
  27
  28#include <drm/drmP.h>
  29#include <drm/drm_atomic.h>
  30#include <drm/drm_plane_helper.h>
  31#include <drm/drm_crtc_helper.h>
  32#include <drm/drm_atomic_helper.h>
  33#include <linux/dma-fence.h>
  34
  35#include "drm_crtc_internal.h"
  36
  37/**
  38 * DOC: overview
  39 *
  40 * This helper library provides implementations of check and commit functions on
  41 * top of the CRTC modeset helper callbacks and the plane helper callbacks. It
  42 * also provides convenience implementations for the atomic state handling
  43 * callbacks for drivers which don't need to subclass the drm core structures to
  44 * add their own additional internal state.
  45 *
  46 * This library also provides default implementations for the check callback in
  47 * drm_atomic_helper_check() and for the commit callback with
  48 * drm_atomic_helper_commit(). But the individual stages and callbacks are
  49 * exposed to allow drivers to mix and match and e.g. use the plane helpers only
  50 * together with a driver private modeset implementation.
  51 *
  52 * This library also provides implementations for all the legacy driver
  53 * interfaces on top of the atomic interface. See drm_atomic_helper_set_config(),
  54 * drm_atomic_helper_disable_plane(), drm_atomic_helper_disable_plane() and the
  55 * various functions to implement set_property callbacks. New drivers must not
  56 * implement these functions themselves but must use the provided helpers.
  57 *
  58 * The atomic helper uses the same function table structures as all other
  59 * modesetting helpers. See the documentation for struct &drm_crtc_helper_funcs,
  60 * struct &drm_encoder_helper_funcs and struct &drm_connector_helper_funcs. It
  61 * also shares the struct &drm_plane_helper_funcs function table with the plane
  62 * helpers.
  63 */
  64static void
  65drm_atomic_helper_plane_changed(struct drm_atomic_state *state,
  66				struct drm_plane_state *plane_state,
  67				struct drm_plane *plane)
  68{
  69	struct drm_crtc_state *crtc_state;
  70
  71	if (plane->state->crtc) {
  72		crtc_state = drm_atomic_get_existing_crtc_state(state,
  73								plane->state->crtc);
  74
  75		if (WARN_ON(!crtc_state))
  76			return;
  77
  78		crtc_state->planes_changed = true;
  79	}
  80
  81	if (plane_state->crtc) {
  82		crtc_state = drm_atomic_get_existing_crtc_state(state,
  83								plane_state->crtc);
  84
  85		if (WARN_ON(!crtc_state))
  86			return;
  87
  88		crtc_state->planes_changed = true;
  89	}
  90}
  91
  92static int handle_conflicting_encoders(struct drm_atomic_state *state,
  93				       bool disable_conflicting_encoders)
  94{
  95	struct drm_connector_state *conn_state;
  96	struct drm_connector *connector;
  97	struct drm_encoder *encoder;
  98	unsigned encoder_mask = 0;
  99	int i, ret;
 100
 101	/*
 102	 * First loop, find all newly assigned encoders from the connectors
 103	 * part of the state. If the same encoder is assigned to multiple
 104	 * connectors bail out.
 105	 */
 106	for_each_connector_in_state(state, connector, conn_state, i) {
 107		const struct drm_connector_helper_funcs *funcs = connector->helper_private;
 108		struct drm_encoder *new_encoder;
 109
 110		if (!conn_state->crtc)
 111			continue;
 112
 113		if (funcs->atomic_best_encoder)
 114			new_encoder = funcs->atomic_best_encoder(connector, conn_state);
 115		else if (funcs->best_encoder)
 116			new_encoder = funcs->best_encoder(connector);
 117		else
 118			new_encoder = drm_atomic_helper_best_encoder(connector);
 119
 120		if (new_encoder) {
 121			if (encoder_mask & (1 << drm_encoder_index(new_encoder))) {
 122				DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] on [CONNECTOR:%d:%s] already assigned\n",
 123					new_encoder->base.id, new_encoder->name,
 124					connector->base.id, connector->name);
 125
 126				return -EINVAL;
 127			}
 128
 129			encoder_mask |= 1 << drm_encoder_index(new_encoder);
 130		}
 131	}
 132
 133	if (!encoder_mask)
 134		return 0;
 135
 136	/*
 137	 * Second loop, iterate over all connectors not part of the state.
 138	 *
 139	 * If a conflicting encoder is found and disable_conflicting_encoders
 140	 * is not set, an error is returned. Userspace can provide a solution
 141	 * through the atomic ioctl.
 142	 *
 143	 * If the flag is set conflicting connectors are removed from the crtc
 144	 * and the crtc is disabled if no encoder is left. This preserves
 145	 * compatibility with the legacy set_config behavior.
 146	 */
 147	drm_for_each_connector(connector, state->dev) {
 148		struct drm_crtc_state *crtc_state;
 149
 150		if (drm_atomic_get_existing_connector_state(state, connector))
 151			continue;
 152
 153		encoder = connector->state->best_encoder;
 154		if (!encoder || !(encoder_mask & (1 << drm_encoder_index(encoder))))
 155			continue;
 156
 157		if (!disable_conflicting_encoders) {
 158			DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] in use on [CRTC:%d:%s] by [CONNECTOR:%d:%s]\n",
 159					 encoder->base.id, encoder->name,
 160					 connector->state->crtc->base.id,
 161					 connector->state->crtc->name,
 162					 connector->base.id, connector->name);
 163			return -EINVAL;
 164		}
 165
 166		conn_state = drm_atomic_get_connector_state(state, connector);
 167		if (IS_ERR(conn_state))
 168			return PTR_ERR(conn_state);
 169
 170		DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] in use on [CRTC:%d:%s], disabling [CONNECTOR:%d:%s]\n",
 171				 encoder->base.id, encoder->name,
 172				 conn_state->crtc->base.id, conn_state->crtc->name,
 173				 connector->base.id, connector->name);
 174
 175		crtc_state = drm_atomic_get_existing_crtc_state(state, conn_state->crtc);
 176
 177		ret = drm_atomic_set_crtc_for_connector(conn_state, NULL);
 178		if (ret)
 179			return ret;
 180
 181		if (!crtc_state->connector_mask) {
 182			ret = drm_atomic_set_mode_prop_for_crtc(crtc_state,
 183								NULL);
 184			if (ret < 0)
 185				return ret;
 186
 187			crtc_state->active = false;
 188		}
 189	}
 190
 191	return 0;
 192}
 193
 194static void
 195set_best_encoder(struct drm_atomic_state *state,
 196		 struct drm_connector_state *conn_state,
 197		 struct drm_encoder *encoder)
 198{
 199	struct drm_crtc_state *crtc_state;
 200	struct drm_crtc *crtc;
 201
 202	if (conn_state->best_encoder) {
 203		/* Unset the encoder_mask in the old crtc state. */
 204		crtc = conn_state->connector->state->crtc;
 205
 206		/* A NULL crtc is an error here because we should have
 207		 *  duplicated a NULL best_encoder when crtc was NULL.
 208		 * As an exception restoring duplicated atomic state
 209		 * during resume is allowed, so don't warn when
 210		 * best_encoder is equal to encoder we intend to set.
 211		 */
 212		WARN_ON(!crtc && encoder != conn_state->best_encoder);
 213		if (crtc) {
 214			crtc_state = drm_atomic_get_existing_crtc_state(state, crtc);
 215
 216			crtc_state->encoder_mask &=
 217				~(1 << drm_encoder_index(conn_state->best_encoder));
 218		}
 219	}
 220
 221	if (encoder) {
 222		crtc = conn_state->crtc;
 223		WARN_ON(!crtc);
 224		if (crtc) {
 225			crtc_state = drm_atomic_get_existing_crtc_state(state, crtc);
 226
 227			crtc_state->encoder_mask |=
 228				1 << drm_encoder_index(encoder);
 229		}
 230	}
 231
 232	conn_state->best_encoder = encoder;
 233}
 234
 235static void
 236steal_encoder(struct drm_atomic_state *state,
 237	      struct drm_encoder *encoder)
 238{
 239	struct drm_crtc_state *crtc_state;
 240	struct drm_connector *connector;
 241	struct drm_connector_state *connector_state;
 242	int i;
 243
 244	for_each_connector_in_state(state, connector, connector_state, i) {
 245		struct drm_crtc *encoder_crtc;
 246
 247		if (connector_state->best_encoder != encoder)
 248			continue;
 249
 250		encoder_crtc = connector->state->crtc;
 251
 252		DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] in use on [CRTC:%d:%s], stealing it\n",
 253				 encoder->base.id, encoder->name,
 254				 encoder_crtc->base.id, encoder_crtc->name);
 255
 256		set_best_encoder(state, connector_state, NULL);
 257
 258		crtc_state = drm_atomic_get_existing_crtc_state(state, encoder_crtc);
 259		crtc_state->connectors_changed = true;
 260
 261		return;
 262	}
 263}
 264
 265static int
 266update_connector_routing(struct drm_atomic_state *state,
 267			 struct drm_connector *connector,
 268			 struct drm_connector_state *connector_state)
 269{
 270	const struct drm_connector_helper_funcs *funcs;
 271	struct drm_encoder *new_encoder;
 272	struct drm_crtc_state *crtc_state;
 273
 274	DRM_DEBUG_ATOMIC("Updating routing for [CONNECTOR:%d:%s]\n",
 275			 connector->base.id,
 276			 connector->name);
 277
 278	if (connector->state->crtc != connector_state->crtc) {
 279		if (connector->state->crtc) {
 280			crtc_state = drm_atomic_get_existing_crtc_state(state, connector->state->crtc);
 281			crtc_state->connectors_changed = true;
 282		}
 283
 284		if (connector_state->crtc) {
 285			crtc_state = drm_atomic_get_existing_crtc_state(state, connector_state->crtc);
 286			crtc_state->connectors_changed = true;
 287		}
 288	}
 289
 290	if (!connector_state->crtc) {
 291		DRM_DEBUG_ATOMIC("Disabling [CONNECTOR:%d:%s]\n",
 292				connector->base.id,
 293				connector->name);
 294
 295		set_best_encoder(state, connector_state, NULL);
 296
 297		return 0;
 298	}
 299
 300	funcs = connector->helper_private;
 301
 302	if (funcs->atomic_best_encoder)
 303		new_encoder = funcs->atomic_best_encoder(connector,
 304							 connector_state);
 305	else if (funcs->best_encoder)
 306		new_encoder = funcs->best_encoder(connector);
 307	else
 308		new_encoder = drm_atomic_helper_best_encoder(connector);
 309
 310	if (!new_encoder) {
 311		DRM_DEBUG_ATOMIC("No suitable encoder found for [CONNECTOR:%d:%s]\n",
 312				 connector->base.id,
 313				 connector->name);
 314		return -EINVAL;
 315	}
 316
 317	if (!drm_encoder_crtc_ok(new_encoder, connector_state->crtc)) {
 318		DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] incompatible with [CRTC:%d]\n",
 319				 new_encoder->base.id,
 320				 new_encoder->name,
 321				 connector_state->crtc->base.id);
 322		return -EINVAL;
 323	}
 324
 325	if (new_encoder == connector_state->best_encoder) {
 326		set_best_encoder(state, connector_state, new_encoder);
 327
 328		DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] keeps [ENCODER:%d:%s], now on [CRTC:%d:%s]\n",
 329				 connector->base.id,
 330				 connector->name,
 331				 new_encoder->base.id,
 332				 new_encoder->name,
 333				 connector_state->crtc->base.id,
 334				 connector_state->crtc->name);
 335
 336		return 0;
 337	}
 338
 339	steal_encoder(state, new_encoder);
 340
 341	set_best_encoder(state, connector_state, new_encoder);
 342
 343	crtc_state = drm_atomic_get_existing_crtc_state(state, connector_state->crtc);
 344	crtc_state->connectors_changed = true;
 345
 346	DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] using [ENCODER:%d:%s] on [CRTC:%d:%s]\n",
 347			 connector->base.id,
 348			 connector->name,
 349			 new_encoder->base.id,
 350			 new_encoder->name,
 351			 connector_state->crtc->base.id,
 352			 connector_state->crtc->name);
 353
 354	return 0;
 355}
 356
 357static int
 358mode_fixup(struct drm_atomic_state *state)
 359{
 360	struct drm_crtc *crtc;
 361	struct drm_crtc_state *crtc_state;
 362	struct drm_connector *connector;
 363	struct drm_connector_state *conn_state;
 364	int i;
 365	int ret;
 366
 367	for_each_crtc_in_state(state, crtc, crtc_state, i) {
 368		if (!crtc_state->mode_changed &&
 369		    !crtc_state->connectors_changed)
 370			continue;
 371
 372		drm_mode_copy(&crtc_state->adjusted_mode, &crtc_state->mode);
 373	}
 374
 375	for_each_connector_in_state(state, connector, conn_state, i) {
 376		const struct drm_encoder_helper_funcs *funcs;
 377		struct drm_encoder *encoder;
 378
 379		WARN_ON(!!conn_state->best_encoder != !!conn_state->crtc);
 380
 381		if (!conn_state->crtc || !conn_state->best_encoder)
 382			continue;
 383
 384		crtc_state = drm_atomic_get_existing_crtc_state(state,
 385								conn_state->crtc);
 386
 387		/*
 388		 * Each encoder has at most one connector (since we always steal
 389		 * it away), so we won't call ->mode_fixup twice.
 390		 */
 391		encoder = conn_state->best_encoder;
 392		funcs = encoder->helper_private;
 393
 394		ret = drm_bridge_mode_fixup(encoder->bridge, &crtc_state->mode,
 395				&crtc_state->adjusted_mode);
 396		if (!ret) {
 397			DRM_DEBUG_ATOMIC("Bridge fixup failed\n");
 398			return -EINVAL;
 399		}
 400
 401		if (funcs && funcs->atomic_check) {
 402			ret = funcs->atomic_check(encoder, crtc_state,
 403						  conn_state);
 404			if (ret) {
 405				DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] check failed\n",
 406						 encoder->base.id, encoder->name);
 407				return ret;
 408			}
 409		} else if (funcs && funcs->mode_fixup) {
 410			ret = funcs->mode_fixup(encoder, &crtc_state->mode,
 411						&crtc_state->adjusted_mode);
 412			if (!ret) {
 413				DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] fixup failed\n",
 414						 encoder->base.id, encoder->name);
 415				return -EINVAL;
 416			}
 417		}
 418	}
 419
 420	for_each_crtc_in_state(state, crtc, crtc_state, i) {
 421		const struct drm_crtc_helper_funcs *funcs;
 422
 423		if (!crtc_state->enable)
 424			continue;
 425
 426		if (!crtc_state->mode_changed &&
 427		    !crtc_state->connectors_changed)
 428			continue;
 429
 430		funcs = crtc->helper_private;
 431		if (!funcs->mode_fixup)
 432			continue;
 433
 434		ret = funcs->mode_fixup(crtc, &crtc_state->mode,
 435					&crtc_state->adjusted_mode);
 436		if (!ret) {
 437			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] fixup failed\n",
 438					 crtc->base.id, crtc->name);
 439			return -EINVAL;
 440		}
 441	}
 442
 443	return 0;
 444}
 445
 446/**
 447 * drm_atomic_helper_check_modeset - validate state object for modeset changes
 448 * @dev: DRM device
 449 * @state: the driver state object
 450 *
 451 * Check the state object to see if the requested state is physically possible.
 452 * This does all the crtc and connector related computations for an atomic
 453 * update and adds any additional connectors needed for full modesets and calls
 454 * down into ->mode_fixup functions of the driver backend.
 455 *
 456 * crtc_state->mode_changed is set when the input mode is changed.
 457 * crtc_state->connectors_changed is set when a connector is added or
 458 * removed from the crtc.
 459 * crtc_state->active_changed is set when crtc_state->active changes,
 460 * which is used for dpms.
 461 * See also: drm_atomic_crtc_needs_modeset()
 462 *
 463 * IMPORTANT:
 464 *
 465 * Drivers which set ->mode_changed (e.g. in their ->atomic_check hooks if a
 466 * plane update can't be done without a full modeset) _must_ call this function
 467 * afterwards after that change. It is permitted to call this function multiple
 468 * times for the same update, e.g. when the ->atomic_check functions depend upon
 469 * the adjusted dotclock for fifo space allocation and watermark computation.
 470 *
 471 * RETURNS:
 472 * Zero for success or -errno
 473 */
 474int
 475drm_atomic_helper_check_modeset(struct drm_device *dev,
 476				struct drm_atomic_state *state)
 477{
 478	struct drm_crtc *crtc;
 479	struct drm_crtc_state *crtc_state;
 480	struct drm_connector *connector;
 481	struct drm_connector_state *connector_state;
 482	int i, ret;
 483
 484	for_each_crtc_in_state(state, crtc, crtc_state, i) {
 485		if (!drm_mode_equal(&crtc->state->mode, &crtc_state->mode)) {
 486			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] mode changed\n",
 487					 crtc->base.id, crtc->name);
 488			crtc_state->mode_changed = true;
 489		}
 490
 491		if (crtc->state->enable != crtc_state->enable) {
 492			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] enable changed\n",
 493					 crtc->base.id, crtc->name);
 494
 495			/*
 496			 * For clarity this assignment is done here, but
 497			 * enable == 0 is only true when there are no
 498			 * connectors and a NULL mode.
 499			 *
 500			 * The other way around is true as well. enable != 0
 501			 * iff connectors are attached and a mode is set.
 502			 */
 503			crtc_state->mode_changed = true;
 504			crtc_state->connectors_changed = true;
 505		}
 506	}
 507
 508	ret = handle_conflicting_encoders(state, state->legacy_set_config);
 509	if (ret)
 510		return ret;
 511
 512	for_each_connector_in_state(state, connector, connector_state, i) {
 513		/*
 514		 * This only sets crtc->connectors_changed for routing changes,
 515		 * drivers must set crtc->connectors_changed themselves when
 516		 * connector properties need to be updated.
 517		 */
 518		ret = update_connector_routing(state, connector,
 519					       connector_state);
 520		if (ret)
 521			return ret;
 522	}
 523
 524	/*
 525	 * After all the routing has been prepared we need to add in any
 526	 * connector which is itself unchanged, but who's crtc changes it's
 527	 * configuration. This must be done before calling mode_fixup in case a
 528	 * crtc only changed its mode but has the same set of connectors.
 529	 */
 530	for_each_crtc_in_state(state, crtc, crtc_state, i) {
 531		bool has_connectors =
 532			!!crtc_state->connector_mask;
 533
 534		/*
 535		 * We must set ->active_changed after walking connectors for
 536		 * otherwise an update that only changes active would result in
 537		 * a full modeset because update_connector_routing force that.
 538		 */
 539		if (crtc->state->active != crtc_state->active) {
 540			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] active changed\n",
 541					 crtc->base.id, crtc->name);
 542			crtc_state->active_changed = true;
 543		}
 544
 545		if (!drm_atomic_crtc_needs_modeset(crtc_state))
 546			continue;
 547
 548		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] needs all connectors, enable: %c, active: %c\n",
 549				 crtc->base.id, crtc->name,
 550				 crtc_state->enable ? 'y' : 'n',
 551				 crtc_state->active ? 'y' : 'n');
 552
 553		ret = drm_atomic_add_affected_connectors(state, crtc);
 554		if (ret != 0)
 555			return ret;
 556
 557		ret = drm_atomic_add_affected_planes(state, crtc);
 558		if (ret != 0)
 559			return ret;
 560
 561		if (crtc_state->enable != has_connectors) {
 562			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] enabled/connectors mismatch\n",
 563					 crtc->base.id, crtc->name);
 564
 565			return -EINVAL;
 566		}
 567	}
 568
 569	return mode_fixup(state);
 570}
 571EXPORT_SYMBOL(drm_atomic_helper_check_modeset);
 572
 573/**
 574 * drm_atomic_helper_check_planes - validate state object for planes changes
 575 * @dev: DRM device
 576 * @state: the driver state object
 577 *
 578 * Check the state object to see if the requested state is physically possible.
 579 * This does all the plane update related checks using by calling into the
 580 * ->atomic_check hooks provided by the driver.
 581 *
 582 * It also sets crtc_state->planes_changed to indicate that a crtc has
 583 * updated planes.
 584 *
 585 * RETURNS:
 586 * Zero for success or -errno
 587 */
 588int
 589drm_atomic_helper_check_planes(struct drm_device *dev,
 590			       struct drm_atomic_state *state)
 591{
 592	struct drm_crtc *crtc;
 593	struct drm_crtc_state *crtc_state;
 594	struct drm_plane *plane;
 595	struct drm_plane_state *plane_state;
 596	int i, ret = 0;
 597
 598	for_each_plane_in_state(state, plane, plane_state, i) {
 599		const struct drm_plane_helper_funcs *funcs;
 600
 601		funcs = plane->helper_private;
 602
 603		drm_atomic_helper_plane_changed(state, plane_state, plane);
 604
 605		if (!funcs || !funcs->atomic_check)
 606			continue;
 607
 608		ret = funcs->atomic_check(plane, plane_state);
 609		if (ret) {
 610			DRM_DEBUG_ATOMIC("[PLANE:%d:%s] atomic driver check failed\n",
 611					 plane->base.id, plane->name);
 612			return ret;
 613		}
 614	}
 615
 616	for_each_crtc_in_state(state, crtc, crtc_state, i) {
 617		const struct drm_crtc_helper_funcs *funcs;
 618
 619		funcs = crtc->helper_private;
 620
 621		if (!funcs || !funcs->atomic_check)
 622			continue;
 623
 624		ret = funcs->atomic_check(crtc, crtc_state);
 625		if (ret) {
 626			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] atomic driver check failed\n",
 627					 crtc->base.id, crtc->name);
 628			return ret;
 629		}
 630	}
 631
 632	return ret;
 633}
 634EXPORT_SYMBOL(drm_atomic_helper_check_planes);
 635
 636/**
 637 * drm_atomic_helper_check - validate state object
 638 * @dev: DRM device
 639 * @state: the driver state object
 640 *
 641 * Check the state object to see if the requested state is physically possible.
 642 * Only crtcs and planes have check callbacks, so for any additional (global)
 643 * checking that a driver needs it can simply wrap that around this function.
 644 * Drivers without such needs can directly use this as their ->atomic_check()
 645 * callback.
 646 *
 647 * This just wraps the two parts of the state checking for planes and modeset
 648 * state in the default order: First it calls drm_atomic_helper_check_modeset()
 649 * and then drm_atomic_helper_check_planes(). The assumption is that the
 650 * ->atomic_check functions depend upon an updated adjusted_mode.clock to
 651 * e.g. properly compute watermarks.
 652 *
 653 * RETURNS:
 654 * Zero for success or -errno
 655 */
 656int drm_atomic_helper_check(struct drm_device *dev,
 657			    struct drm_atomic_state *state)
 658{
 659	int ret;
 660
 661	ret = drm_atomic_helper_check_modeset(dev, state);
 662	if (ret)
 663		return ret;
 664
 665	ret = drm_atomic_helper_check_planes(dev, state);
 666	if (ret)
 667		return ret;
 668
 669	return ret;
 670}
 671EXPORT_SYMBOL(drm_atomic_helper_check);
 672
 673static void
 674disable_outputs(struct drm_device *dev, struct drm_atomic_state *old_state)
 675{
 676	struct drm_connector *connector;
 677	struct drm_connector_state *old_conn_state;
 678	struct drm_crtc *crtc;
 679	struct drm_crtc_state *old_crtc_state;
 680	int i;
 681
 682	for_each_connector_in_state(old_state, connector, old_conn_state, i) {
 683		const struct drm_encoder_helper_funcs *funcs;
 684		struct drm_encoder *encoder;
 685
 686		/* Shut down everything that's in the changeset and currently
 687		 * still on. So need to check the old, saved state. */
 688		if (!old_conn_state->crtc)
 689			continue;
 690
 691		old_crtc_state = drm_atomic_get_existing_crtc_state(old_state,
 692								    old_conn_state->crtc);
 693
 694		if (!old_crtc_state->active ||
 695		    !drm_atomic_crtc_needs_modeset(old_conn_state->crtc->state))
 696			continue;
 697
 698		encoder = old_conn_state->best_encoder;
 699
 700		/* We shouldn't get this far if we didn't previously have
 701		 * an encoder.. but WARN_ON() rather than explode.
 702		 */
 703		if (WARN_ON(!encoder))
 704			continue;
 705
 706		funcs = encoder->helper_private;
 707
 708		DRM_DEBUG_ATOMIC("disabling [ENCODER:%d:%s]\n",
 709				 encoder->base.id, encoder->name);
 710
 711		/*
 712		 * Each encoder has at most one connector (since we always steal
 713		 * it away), so we won't call disable hooks twice.
 714		 */
 715		drm_bridge_disable(encoder->bridge);
 716
 717		/* Right function depends upon target state. */
 718		if (funcs) {
 719			if (connector->state->crtc && funcs->prepare)
 720				funcs->prepare(encoder);
 721			else if (funcs->disable)
 722				funcs->disable(encoder);
 723			else if (funcs->dpms)
 724				funcs->dpms(encoder, DRM_MODE_DPMS_OFF);
 725		}
 726
 727		drm_bridge_post_disable(encoder->bridge);
 728	}
 729
 730	for_each_crtc_in_state(old_state, crtc, old_crtc_state, i) {
 731		const struct drm_crtc_helper_funcs *funcs;
 732
 733		/* Shut down everything that needs a full modeset. */
 734		if (!drm_atomic_crtc_needs_modeset(crtc->state))
 735			continue;
 736
 737		if (!old_crtc_state->active)
 738			continue;
 739
 740		funcs = crtc->helper_private;
 741
 742		DRM_DEBUG_ATOMIC("disabling [CRTC:%d:%s]\n",
 743				 crtc->base.id, crtc->name);
 744
 745
 746		/* Right function depends upon target state. */
 747		if (crtc->state->enable && funcs->prepare)
 748			funcs->prepare(crtc);
 749		else if (funcs->atomic_disable)
 750			funcs->atomic_disable(crtc, old_crtc_state);
 751		else if (funcs->disable)
 752			funcs->disable(crtc);
 753		else
 754			funcs->dpms(crtc, DRM_MODE_DPMS_OFF);
 755	}
 756}
 757
 758/**
 759 * drm_atomic_helper_update_legacy_modeset_state - update legacy modeset state
 760 * @dev: DRM device
 761 * @old_state: atomic state object with old state structures
 762 *
 763 * This function updates all the various legacy modeset state pointers in
 764 * connectors, encoders and crtcs. It also updates the timestamping constants
 765 * used for precise vblank timestamps by calling
 766 * drm_calc_timestamping_constants().
 767 *
 768 * Drivers can use this for building their own atomic commit if they don't have
 769 * a pure helper-based modeset implementation.
 770 */
 771void
 772drm_atomic_helper_update_legacy_modeset_state(struct drm_device *dev,
 773					      struct drm_atomic_state *old_state)
 774{
 775	struct drm_connector *connector;
 776	struct drm_connector_state *old_conn_state;
 777	struct drm_crtc *crtc;
 778	struct drm_crtc_state *old_crtc_state;
 779	int i;
 780
 781	/* clear out existing links and update dpms */
 782	for_each_connector_in_state(old_state, connector, old_conn_state, i) {
 783		if (connector->encoder) {
 784			WARN_ON(!connector->encoder->crtc);
 785
 786			connector->encoder->crtc = NULL;
 787			connector->encoder = NULL;
 788		}
 789
 790		crtc = connector->state->crtc;
 791		if ((!crtc && old_conn_state->crtc) ||
 792		    (crtc && drm_atomic_crtc_needs_modeset(crtc->state))) {
 793			struct drm_property *dpms_prop =
 794				dev->mode_config.dpms_property;
 795			int mode = DRM_MODE_DPMS_OFF;
 796
 797			if (crtc && crtc->state->active)
 798				mode = DRM_MODE_DPMS_ON;
 799
 800			connector->dpms = mode;
 801			drm_object_property_set_value(&connector->base,
 802						      dpms_prop, mode);
 803		}
 804	}
 805
 806	/* set new links */
 807	for_each_connector_in_state(old_state, connector, old_conn_state, i) {
 808		if (!connector->state->crtc)
 809			continue;
 810
 811		if (WARN_ON(!connector->state->best_encoder))
 812			continue;
 813
 814		connector->encoder = connector->state->best_encoder;
 815		connector->encoder->crtc = connector->state->crtc;
 816	}
 817
 818	/* set legacy state in the crtc structure */
 819	for_each_crtc_in_state(old_state, crtc, old_crtc_state, i) {
 820		struct drm_plane *primary = crtc->primary;
 821
 822		crtc->mode = crtc->state->mode;
 823		crtc->enabled = crtc->state->enable;
 824
 825		if (drm_atomic_get_existing_plane_state(old_state, primary) &&
 826		    primary->state->crtc == crtc) {
 827			crtc->x = primary->state->src_x >> 16;
 828			crtc->y = primary->state->src_y >> 16;
 829		}
 830
 831		if (crtc->state->enable)
 832			drm_calc_timestamping_constants(crtc,
 833							&crtc->state->adjusted_mode);
 834	}
 835}
 836EXPORT_SYMBOL(drm_atomic_helper_update_legacy_modeset_state);
 837
 838static void
 839crtc_set_mode(struct drm_device *dev, struct drm_atomic_state *old_state)
 840{
 841	struct drm_crtc *crtc;
 842	struct drm_crtc_state *old_crtc_state;
 843	struct drm_connector *connector;
 844	struct drm_connector_state *old_conn_state;
 845	int i;
 846
 847	for_each_crtc_in_state(old_state, crtc, old_crtc_state, i) {
 848		const struct drm_crtc_helper_funcs *funcs;
 849
 850		if (!crtc->state->mode_changed)
 851			continue;
 852
 853		funcs = crtc->helper_private;
 854
 855		if (crtc->state->enable && funcs->mode_set_nofb) {
 856			DRM_DEBUG_ATOMIC("modeset on [CRTC:%d:%s]\n",
 857					 crtc->base.id, crtc->name);
 858
 859			funcs->mode_set_nofb(crtc);
 860		}
 861	}
 862
 863	for_each_connector_in_state(old_state, connector, old_conn_state, i) {
 864		const struct drm_encoder_helper_funcs *funcs;
 865		struct drm_crtc_state *new_crtc_state;
 866		struct drm_encoder *encoder;
 867		struct drm_display_mode *mode, *adjusted_mode;
 868
 869		if (!connector->state->best_encoder)
 870			continue;
 871
 872		encoder = connector->state->best_encoder;
 873		funcs = encoder->helper_private;
 874		new_crtc_state = connector->state->crtc->state;
 875		mode = &new_crtc_state->mode;
 876		adjusted_mode = &new_crtc_state->adjusted_mode;
 877
 878		if (!new_crtc_state->mode_changed)
 879			continue;
 880
 881		DRM_DEBUG_ATOMIC("modeset on [ENCODER:%d:%s]\n",
 882				 encoder->base.id, encoder->name);
 883
 884		/*
 885		 * Each encoder has at most one connector (since we always steal
 886		 * it away), so we won't call mode_set hooks twice.
 887		 */
 888		if (funcs && funcs->atomic_mode_set) {
 889			funcs->atomic_mode_set(encoder, new_crtc_state,
 890					       connector->state);
 891		} else if (funcs && funcs->mode_set) {
 892			funcs->mode_set(encoder, mode, adjusted_mode);
 893		}
 894
 895		drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
 896	}
 897}
 898
 899/**
 900 * drm_atomic_helper_commit_modeset_disables - modeset commit to disable outputs
 901 * @dev: DRM device
 902 * @old_state: atomic state object with old state structures
 903 *
 904 * This function shuts down all the outputs that need to be shut down and
 905 * prepares them (if required) with the new mode.
 906 *
 907 * For compatibility with legacy crtc helpers this should be called before
 908 * drm_atomic_helper_commit_planes(), which is what the default commit function
 909 * does. But drivers with different needs can group the modeset commits together
 910 * and do the plane commits at the end. This is useful for drivers doing runtime
 911 * PM since planes updates then only happen when the CRTC is actually enabled.
 912 */
 913void drm_atomic_helper_commit_modeset_disables(struct drm_device *dev,
 914					       struct drm_atomic_state *old_state)
 915{
 916	disable_outputs(dev, old_state);
 917
 918	drm_atomic_helper_update_legacy_modeset_state(dev, old_state);
 919
 920	crtc_set_mode(dev, old_state);
 921}
 922EXPORT_SYMBOL(drm_atomic_helper_commit_modeset_disables);
 923
 924/**
 925 * drm_atomic_helper_commit_modeset_enables - modeset commit to enable outputs
 926 * @dev: DRM device
 927 * @old_state: atomic state object with old state structures
 928 *
 929 * This function enables all the outputs with the new configuration which had to
 930 * be turned off for the update.
 931 *
 932 * For compatibility with legacy crtc helpers this should be called after
 933 * drm_atomic_helper_commit_planes(), which is what the default commit function
 934 * does. But drivers with different needs can group the modeset commits together
 935 * and do the plane commits at the end. This is useful for drivers doing runtime
 936 * PM since planes updates then only happen when the CRTC is actually enabled.
 937 */
 938void drm_atomic_helper_commit_modeset_enables(struct drm_device *dev,
 939					      struct drm_atomic_state *old_state)
 940{
 941	struct drm_crtc *crtc;
 942	struct drm_crtc_state *old_crtc_state;
 943	struct drm_connector *connector;
 944	struct drm_connector_state *old_conn_state;
 945	int i;
 946
 947	for_each_crtc_in_state(old_state, crtc, old_crtc_state, i) {
 948		const struct drm_crtc_helper_funcs *funcs;
 949
 950		/* Need to filter out CRTCs where only planes change. */
 951		if (!drm_atomic_crtc_needs_modeset(crtc->state))
 952			continue;
 953
 954		if (!crtc->state->active)
 955			continue;
 956
 957		funcs = crtc->helper_private;
 958
 959		if (crtc->state->enable) {
 960			DRM_DEBUG_ATOMIC("enabling [CRTC:%d:%s]\n",
 961					 crtc->base.id, crtc->name);
 962
 963			if (funcs->enable)
 964				funcs->enable(crtc);
 965			else
 966				funcs->commit(crtc);
 967		}
 968	}
 969
 970	for_each_connector_in_state(old_state, connector, old_conn_state, i) {
 971		const struct drm_encoder_helper_funcs *funcs;
 972		struct drm_encoder *encoder;
 973
 974		if (!connector->state->best_encoder)
 975			continue;
 976
 977		if (!connector->state->crtc->state->active ||
 978		    !drm_atomic_crtc_needs_modeset(connector->state->crtc->state))
 979			continue;
 980
 981		encoder = connector->state->best_encoder;
 982		funcs = encoder->helper_private;
 983
 984		DRM_DEBUG_ATOMIC("enabling [ENCODER:%d:%s]\n",
 985				 encoder->base.id, encoder->name);
 986
 987		/*
 988		 * Each encoder has at most one connector (since we always steal
 989		 * it away), so we won't call enable hooks twice.
 990		 */
 991		drm_bridge_pre_enable(encoder->bridge);
 992
 993		if (funcs) {
 994			if (funcs->enable)
 995				funcs->enable(encoder);
 996			else if (funcs->commit)
 997				funcs->commit(encoder);
 998		}
 999
1000		drm_bridge_enable(encoder->bridge);
1001	}
1002}
1003EXPORT_SYMBOL(drm_atomic_helper_commit_modeset_enables);
1004
1005/**
1006 * drm_atomic_helper_wait_for_fences - wait for fences stashed in plane state
1007 * @dev: DRM device
1008 * @state: atomic state object with old state structures
1009 * @pre_swap: If true, do an interruptible wait, and @state is the new state.
1010 * 	Otherwise @state is the old state.
1011 *
1012 * For implicit sync, driver should fish the exclusive fence out from the
1013 * incoming fb's and stash it in the drm_plane_state.  This is called after
1014 * drm_atomic_helper_swap_state() so it uses the current plane state (and
1015 * just uses the atomic state to find the changed planes)
1016 *
1017 * Note that @pre_swap is needed since the point where we block for fences moves
1018 * around depending upon whether an atomic commit is blocking or
1019 * non-blocking. For async commit all waiting needs to happen after
1020 * drm_atomic_helper_swap_state() is called, but for synchronous commits we want
1021 * to wait **before** we do anything that can't be easily rolled back. That is
1022 * before we call drm_atomic_helper_swap_state().
1023 *
1024 * Returns zero if success or < 0 if dma_fence_wait() fails.
1025 */
1026int drm_atomic_helper_wait_for_fences(struct drm_device *dev,
1027				      struct drm_atomic_state *state,
1028				      bool pre_swap)
1029{
1030	struct drm_plane *plane;
1031	struct drm_plane_state *plane_state;
1032	int i, ret;
1033
1034	for_each_plane_in_state(state, plane, plane_state, i) {
1035		if (!pre_swap)
1036			plane_state = plane->state;
1037
1038		if (!plane_state->fence)
1039			continue;
1040
1041		WARN_ON(!plane_state->fb);
1042
1043		/*
1044		 * If waiting for fences pre-swap (ie: nonblock), userspace can
1045		 * still interrupt the operation. Instead of blocking until the
1046		 * timer expires, make the wait interruptible.
1047		 */
1048		ret = dma_fence_wait(plane_state->fence, pre_swap);
1049		if (ret)
1050			return ret;
1051
1052		dma_fence_put(plane_state->fence);
1053		plane_state->fence = NULL;
1054	}
1055
1056	return 0;
1057}
1058EXPORT_SYMBOL(drm_atomic_helper_wait_for_fences);
1059
1060/**
1061 * drm_atomic_helper_framebuffer_changed - check if framebuffer has changed
1062 * @dev: DRM device
1063 * @old_state: atomic state object with old state structures
1064 * @crtc: DRM crtc
1065 *
1066 * Checks whether the framebuffer used for this CRTC changes as a result of
1067 * the atomic update.  This is useful for drivers which cannot use
1068 * drm_atomic_helper_wait_for_vblanks() and need to reimplement its
1069 * functionality.
1070 *
1071 * Returns:
1072 * true if the framebuffer changed.
1073 */
1074bool drm_atomic_helper_framebuffer_changed(struct drm_device *dev,
1075					   struct drm_atomic_state *old_state,
1076					   struct drm_crtc *crtc)
1077{
1078	struct drm_plane *plane;
1079	struct drm_plane_state *old_plane_state;
1080	int i;
1081
1082	for_each_plane_in_state(old_state, plane, old_plane_state, i) {
1083		if (plane->state->crtc != crtc &&
1084		    old_plane_state->crtc != crtc)
1085			continue;
1086
1087		if (plane->state->fb != old_plane_state->fb)
1088			return true;
1089	}
1090
1091	return false;
1092}
1093EXPORT_SYMBOL(drm_atomic_helper_framebuffer_changed);
1094
1095/**
1096 * drm_atomic_helper_wait_for_vblanks - wait for vblank on crtcs
1097 * @dev: DRM device
1098 * @old_state: atomic state object with old state structures
1099 *
1100 * Helper to, after atomic commit, wait for vblanks on all effected
1101 * crtcs (ie. before cleaning up old framebuffers using
1102 * drm_atomic_helper_cleanup_planes()). It will only wait on crtcs where the
1103 * framebuffers have actually changed to optimize for the legacy cursor and
1104 * plane update use-case.
1105 */
1106void
1107drm_atomic_helper_wait_for_vblanks(struct drm_device *dev,
1108		struct drm_atomic_state *old_state)
1109{
1110	struct drm_crtc *crtc;
1111	struct drm_crtc_state *old_crtc_state;
1112	int i, ret;
1113
1114	for_each_crtc_in_state(old_state, crtc, old_crtc_state, i) {
1115		/* No one cares about the old state, so abuse it for tracking
1116		 * and store whether we hold a vblank reference (and should do a
1117		 * vblank wait) in the ->enable boolean. */
1118		old_crtc_state->enable = false;
1119
1120		if (!crtc->state->enable)
1121			continue;
1122
1123		/* Legacy cursor ioctls are completely unsynced, and userspace
1124		 * relies on that (by doing tons of cursor updates). */
1125		if (old_state->legacy_cursor_update)
1126			continue;
1127
1128		if (!drm_atomic_helper_framebuffer_changed(dev,
1129				old_state, crtc))
1130			continue;
1131
1132		ret = drm_crtc_vblank_get(crtc);
1133		if (ret != 0)
1134			continue;
1135
1136		old_crtc_state->enable = true;
1137		old_crtc_state->last_vblank_count = drm_crtc_vblank_count(crtc);
1138	}
1139
1140	for_each_crtc_in_state(old_state, crtc, old_crtc_state, i) {
1141		if (!old_crtc_state->enable)
1142			continue;
1143
1144		ret = wait_event_timeout(dev->vblank[i].queue,
1145				old_crtc_state->last_vblank_count !=
1146					drm_crtc_vblank_count(crtc),
1147				msecs_to_jiffies(50));
1148
1149		WARN(!ret, "[CRTC:%d] vblank wait timed out\n", crtc->base.id);
1150
1151		drm_crtc_vblank_put(crtc);
1152	}
1153}
1154EXPORT_SYMBOL(drm_atomic_helper_wait_for_vblanks);
1155
1156/**
1157 * drm_atomic_helper_commit_tail - commit atomic update to hardware
1158 * @old_state: atomic state object with old state structures
1159 *
1160 * This is the default implemenation for the ->atomic_commit_tail() hook of the
1161 * &drm_mode_config_helper_funcs vtable.
1162 *
1163 * Note that the default ordering of how the various stages are called is to
1164 * match the legacy modeset helper library closest. One peculiarity of that is
1165 * that it doesn't mesh well with runtime PM at all.
1166 *
1167 * For drivers supporting runtime PM the recommended sequence is instead ::
1168 *
1169 *     drm_atomic_helper_commit_modeset_disables(dev, old_state);
1170 *
1171 *     drm_atomic_helper_commit_modeset_enables(dev, old_state);
1172 *
1173 *     drm_atomic_helper_commit_planes(dev, old_state,
1174 *                                     DRM_PLANE_COMMIT_ACTIVE_ONLY);
1175 *
1176 * for committing the atomic update to hardware.  See the kerneldoc entries for
1177 * these three functions for more details.
1178 */
1179void drm_atomic_helper_commit_tail(struct drm_atomic_state *old_state)
1180{
1181	struct drm_device *dev = old_state->dev;
1182
1183	drm_atomic_helper_commit_modeset_disables(dev, old_state);
1184
1185	drm_atomic_helper_commit_planes(dev, old_state, 0);
1186
1187	drm_atomic_helper_commit_modeset_enables(dev, old_state);
1188
1189	drm_atomic_helper_commit_hw_done(old_state);
1190
1191	drm_atomic_helper_wait_for_vblanks(dev, old_state);
1192
1193	drm_atomic_helper_cleanup_planes(dev, old_state);
1194}
1195EXPORT_SYMBOL(drm_atomic_helper_commit_tail);
1196
1197static void commit_tail(struct drm_atomic_state *old_state)
1198{
1199	struct drm_device *dev = old_state->dev;
1200	struct drm_mode_config_helper_funcs *funcs;
1201
1202	funcs = dev->mode_config.helper_private;
1203
1204	drm_atomic_helper_wait_for_fences(dev, old_state, false);
1205
1206	drm_atomic_helper_wait_for_dependencies(old_state);
1207
1208	if (funcs && funcs->atomic_commit_tail)
1209		funcs->atomic_commit_tail(old_state);
1210	else
1211		drm_atomic_helper_commit_tail(old_state);
1212
1213	drm_atomic_helper_commit_cleanup_done(old_state);
1214
1215	drm_atomic_state_put(old_state);
1216}
1217
1218static void commit_work(struct work_struct *work)
1219{
1220	struct drm_atomic_state *state = container_of(work,
1221						      struct drm_atomic_state,
1222						      commit_work);
1223	commit_tail(state);
1224}
1225
1226/**
1227 * drm_atomic_helper_commit - commit validated state object
1228 * @dev: DRM device
1229 * @state: the driver state object
1230 * @nonblock: whether nonblocking behavior is requested.
1231 *
1232 * This function commits a with drm_atomic_helper_check() pre-validated state
1233 * object. This can still fail when e.g. the framebuffer reservation fails. This
1234 * function implements nonblocking commits, using
1235 * drm_atomic_helper_setup_commit() and related functions.
1236 *
1237 * Committing the actual hardware state is done through the
1238 * ->atomic_commit_tail() callback of the &drm_mode_config_helper_funcs vtable,
1239 * or it's default implementation drm_atomic_helper_commit_tail().
1240 *
1241 * RETURNS:
1242 * Zero for success or -errno.
1243 */
1244int drm_atomic_helper_commit(struct drm_device *dev,
1245			     struct drm_atomic_state *state,
1246			     bool nonblock)
1247{
1248	int ret;
1249
1250	ret = drm_atomic_helper_setup_commit(state, nonblock);
1251	if (ret)
1252		return ret;
1253
1254	INIT_WORK(&state->commit_work, commit_work);
1255
1256	ret = drm_atomic_helper_prepare_planes(dev, state);
1257	if (ret)
1258		return ret;
1259
1260	if (!nonblock) {
1261		ret = drm_atomic_helper_wait_for_fences(dev, state, true);
1262		if (ret) {
1263			drm_atomic_helper_cleanup_planes(dev, state);
1264			return ret;
1265		}
1266	}
1267
1268	/*
1269	 * This is the point of no return - everything below never fails except
1270	 * when the hw goes bonghits. Which means we can commit the new state on
1271	 * the software side now.
1272	 */
1273
1274	drm_atomic_helper_swap_state(state, true);
1275
1276	/*
1277	 * Everything below can be run asynchronously without the need to grab
1278	 * any modeset locks at all under one condition: It must be guaranteed
1279	 * that the asynchronous work has either been cancelled (if the driver
1280	 * supports it, which at least requires that the framebuffers get
1281	 * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
1282	 * before the new state gets committed on the software side with
1283	 * drm_atomic_helper_swap_state().
1284	 *
1285	 * This scheme allows new atomic state updates to be prepared and
1286	 * checked in parallel to the asynchronous completion of the previous
1287	 * update. Which is important since compositors need to figure out the
1288	 * composition of the next frame right after having submitted the
1289	 * current layout.
1290	 *
1291	 * NOTE: Commit work has multiple phases, first hardware commit, then
1292	 * cleanup. We want them to overlap, hence need system_unbound_wq to
1293	 * make sure work items don't artifically stall on each another.
1294	 */
1295
1296	drm_atomic_state_get(state);
1297	if (nonblock)
1298		queue_work(system_unbound_wq, &state->commit_work);
1299	else
1300		commit_tail(state);
1301
1302	return 0;
1303}
1304EXPORT_SYMBOL(drm_atomic_helper_commit);
1305
1306/**
1307 * DOC: implementing nonblocking commit
1308 *
1309 * Nonblocking atomic commits have to be implemented in the following sequence:
1310 *
1311 * 1. Run drm_atomic_helper_prepare_planes() first. This is the only function
1312 * which commit needs to call which can fail, so we want to run it first and
1313 * synchronously.
1314 *
1315 * 2. Synchronize with any outstanding nonblocking commit worker threads which
1316 * might be affected the new state update. This can be done by either cancelling
1317 * or flushing the work items, depending upon whether the driver can deal with
1318 * cancelled updates. Note that it is important to ensure that the framebuffer
1319 * cleanup is still done when cancelling.
1320 *
1321 * Asynchronous workers need to have sufficient parallelism to be able to run
1322 * different atomic commits on different CRTCs in parallel. The simplest way to
1323 * achive this is by running them on the &system_unbound_wq work queue. Note
1324 * that drivers are not required to split up atomic commits and run an
1325 * individual commit in parallel - userspace is supposed to do that if it cares.
1326 * But it might be beneficial to do that for modesets, since those necessarily
1327 * must be done as one global operation, and enabling or disabling a CRTC can
1328 * take a long time. But even that is not required.
1329 *
1330 * 3. The software state is updated synchronously with
1331 * drm_atomic_helper_swap_state(). Doing this under the protection of all modeset
1332 * locks means concurrent callers never see inconsistent state. And doing this
1333 * while it's guaranteed that no relevant nonblocking worker runs means that
1334 * nonblocking workers do not need grab any locks. Actually they must not grab
1335 * locks, for otherwise the work flushing will deadlock.
1336 *
1337 * 4. Schedule a work item to do all subsequent steps, using the split-out
1338 * commit helpers: a) pre-plane commit b) plane commit c) post-plane commit and
1339 * then cleaning up the framebuffers after the old framebuffer is no longer
1340 * being displayed.
1341 *
1342 * The above scheme is implemented in the atomic helper libraries in
1343 * drm_atomic_helper_commit() using a bunch of helper functions. See
1344 * drm_atomic_helper_setup_commit() for a starting point.
1345 */
1346
1347static int stall_checks(struct drm_crtc *crtc, bool nonblock)
1348{
1349	struct drm_crtc_commit *commit, *stall_commit = NULL;
1350	bool completed = true;
1351	int i;
1352	long ret = 0;
1353
1354	spin_lock(&crtc->commit_lock);
1355	i = 0;
1356	list_for_each_entry(commit, &crtc->commit_list, commit_entry) {
1357		if (i == 0) {
1358			completed = try_wait_for_completion(&commit->flip_done);
1359			/* Userspace is not allowed to get ahead of the previous
1360			 * commit with nonblocking ones. */
1361			if (!completed && nonblock) {
1362				spin_unlock(&crtc->commit_lock);
1363				return -EBUSY;
1364			}
1365		} else if (i == 1) {
1366			stall_commit = commit;
1367			drm_crtc_commit_get(stall_commit);
1368			break;
1369		}
1370
1371		i++;
1372	}
1373	spin_unlock(&crtc->commit_lock);
1374
1375	if (!stall_commit)
1376		return 0;
1377
1378	/* We don't want to let commits get ahead of cleanup work too much,
1379	 * stalling on 2nd previous commit means triple-buffer won't ever stall.
1380	 */
1381	ret = wait_for_completion_interruptible_timeout(&stall_commit->cleanup_done,
1382							10*HZ);
1383	if (ret == 0)
1384		DRM_ERROR("[CRTC:%d:%s] cleanup_done timed out\n",
1385			  crtc->base.id, crtc->name);
1386
1387	drm_crtc_commit_put(stall_commit);
1388
1389	return ret < 0 ? ret : 0;
1390}
1391
1392void release_crtc_commit(struct completion *completion)
1393{
1394	struct drm_crtc_commit *commit = container_of(completion,
1395						      typeof(*commit),
1396						      flip_done);
1397
1398	drm_crtc_commit_put(commit);
1399}
1400
1401/**
1402 * drm_atomic_helper_setup_commit - setup possibly nonblocking commit
1403 * @state: new modeset state to be committed
1404 * @nonblock: whether nonblocking behavior is requested.
1405 *
1406 * This function prepares @state to be used by the atomic helper's support for
1407 * nonblocking commits. Drivers using the nonblocking commit infrastructure
1408 * should always call this function from their ->atomic_commit hook.
1409 *
1410 * To be able to use this support drivers need to use a few more helper
1411 * functions. drm_atomic_helper_wait_for_dependencies() must be called before
1412 * actually committing the hardware state, and for nonblocking commits this call
1413 * must be placed in the async worker. See also drm_atomic_helper_swap_state()
1414 * and it's stall parameter, for when a driver's commit hooks look at the
1415 * ->state pointers of struct &drm_crtc, &drm_plane or &drm_connector directly.
1416 *
1417 * Completion of the hardware commit step must be signalled using
1418 * drm_atomic_helper_commit_hw_done(). After this step the driver is not allowed
1419 * to read or change any permanent software or hardware modeset state. The only
1420 * exception is state protected by other means than &drm_modeset_lock locks.
1421 * Only the free standing @state with pointers to the old state structures can
1422 * be inspected, e.g. to clean up old buffers using
1423 * drm_atomic_helper_cleanup_planes().
1424 *
1425 * At the very end, before cleaning up @state drivers must call
1426 * drm_atomic_helper_commit_cleanup_done().
1427 *
1428 * This is all implemented by in drm_atomic_helper_commit(), giving drivers a
1429 * complete and esay-to-use default implementation of the atomic_commit() hook.
1430 *
1431 * The tracking of asynchronously executed and still pending commits is done
1432 * using the core structure &drm_crtc_commit.
1433 *
1434 * By default there's no need to clean up resources allocated by this function
1435 * explicitly: drm_atomic_state_default_clear() will take care of that
1436 * automatically.
1437 *
1438 * Returns:
1439 *
1440 * 0 on success. -EBUSY when userspace schedules nonblocking commits too fast,
1441 * -ENOMEM on allocation failures and -EINTR when a signal is pending.
1442 */
1443int drm_atomic_helper_setup_commit(struct drm_atomic_state *state,
1444				   bool nonblock)
1445{
1446	struct drm_crtc *crtc;
1447	struct drm_crtc_state *crtc_state;
1448	struct drm_crtc_commit *commit;
1449	int i, ret;
1450
1451	for_each_crtc_in_state(state, crtc, crtc_state, i) {
1452		commit = kzalloc(sizeof(*commit), GFP_KERNEL);
1453		if (!commit)
1454			return -ENOMEM;
1455
1456		init_completion(&commit->flip_done);
1457		init_completion(&commit->hw_done);
1458		init_completion(&commit->cleanup_done);
1459		INIT_LIST_HEAD(&commit->commit_entry);
1460		kref_init(&commit->ref);
1461		commit->crtc = crtc;
1462
1463		state->crtcs[i].commit = commit;
1464
1465		ret = stall_checks(crtc, nonblock);
1466		if (ret)
1467			return ret;
1468
1469		/* Drivers only send out events when at least either current or
1470		 * new CRTC state is active. Complete right away if everything
1471		 * stays off. */
1472		if (!crtc->state->active && !crtc_state->active) {
1473			complete_all(&commit->flip_done);
1474			continue;
1475		}
1476
1477		/* Legacy cursor updates are fully unsynced. */
1478		if (state->legacy_cursor_update) {
1479			complete_all(&commit->flip_done);
1480			continue;
1481		}
1482
1483		if (!crtc_state->event) {
1484			commit->event = kzalloc(sizeof(*commit->event),
1485						GFP_KERNEL);
1486			if (!commit->event)
1487				return -ENOMEM;
1488
1489			crtc_state->event = commit->event;
1490		}
1491
1492		crtc_state->event->base.completion = &commit->flip_done;
1493		crtc_state->event->base.completion_release = release_crtc_commit;
1494		drm_crtc_commit_get(commit);
1495	}
1496
1497	return 0;
1498}
1499EXPORT_SYMBOL(drm_atomic_helper_setup_commit);
1500
1501
1502static struct drm_crtc_commit *preceeding_commit(struct drm_crtc *crtc)
1503{
1504	struct drm_crtc_commit *commit;
1505	int i = 0;
1506
1507	list_for_each_entry(commit, &crtc->commit_list, commit_entry) {
1508		/* skip the first entry, that's the current commit */
1509		if (i == 1)
1510			return commit;
1511		i++;
1512	}
1513
1514	return NULL;
1515}
1516
1517/**
1518 * drm_atomic_helper_wait_for_dependencies - wait for required preceeding commits
1519 * @old_state: atomic state object with old state structures
1520 *
1521 * This function waits for all preceeding commits that touch the same CRTC as
1522 * @old_state to both be committed to the hardware (as signalled by
1523 * drm_atomic_helper_commit_hw_done) and executed by the hardware (as signalled
1524 * by calling drm_crtc_vblank_send_event on the event member of
1525 * &drm_crtc_state).
1526 *
1527 * This is part of the atomic helper support for nonblocking commits, see
1528 * drm_atomic_helper_setup_commit() for an overview.
1529 */
1530void drm_atomic_helper_wait_for_dependencies(struct drm_atomic_state *old_state)
1531{
1532	struct drm_crtc *crtc;
1533	struct drm_crtc_state *crtc_state;
1534	struct drm_crtc_commit *commit;
1535	int i;
1536	long ret;
1537
1538	for_each_crtc_in_state(old_state, crtc, crtc_state, i) {
1539		spin_lock(&crtc->commit_lock);
1540		commit = preceeding_commit(crtc);
1541		if (commit)
1542			drm_crtc_commit_get(commit);
1543		spin_unlock(&crtc->commit_lock);
1544
1545		if (!commit)
1546			continue;
1547
1548		ret = wait_for_completion_timeout(&commit->hw_done,
1549						  10*HZ);
1550		if (ret == 0)
1551			DRM_ERROR("[CRTC:%d:%s] hw_done timed out\n",
1552				  crtc->base.id, crtc->name);
1553
1554		/* Currently no support for overwriting flips, hence
1555		 * stall for previous one to execute completely. */
1556		ret = wait_for_completion_timeout(&commit->flip_done,
1557						  10*HZ);
1558		if (ret == 0)
1559			DRM_ERROR("[CRTC:%d:%s] flip_done timed out\n",
1560				  crtc->base.id, crtc->name);
1561
1562		drm_crtc_commit_put(commit);
1563	}
1564}
1565EXPORT_SYMBOL(drm_atomic_helper_wait_for_dependencies);
1566
1567/**
1568 * drm_atomic_helper_commit_hw_done - setup possible nonblocking commit
1569 * @old_state: atomic state object with old state structures
1570 *
1571 * This function is used to signal completion of the hardware commit step. After
1572 * this step the driver is not allowed to read or change any permanent software
1573 * or hardware modeset state. The only exception is state protected by other
1574 * means than &drm_modeset_lock locks.
1575 *
1576 * Drivers should try to postpone any expensive or delayed cleanup work after
1577 * this function is called.
1578 *
1579 * This is part of the atomic helper support for nonblocking commits, see
1580 * drm_atomic_helper_setup_commit() for an overview.
1581 */
1582void drm_atomic_helper_commit_hw_done(struct drm_atomic_state *old_state)
1583{
1584	struct drm_crtc *crtc;
1585	struct drm_crtc_state *crtc_state;
1586	struct drm_crtc_commit *commit;
1587	int i;
1588
1589	for_each_crtc_in_state(old_state, crtc, crtc_state, i) {
1590		commit = old_state->crtcs[i].commit;
1591		if (!commit)
1592			continue;
1593
1594		/* backend must have consumed any event by now */
1595		WARN_ON(crtc->state->event);
1596		spin_lock(&crtc->commit_lock);
1597		complete_all(&commit->hw_done);
1598		spin_unlock(&crtc->commit_lock);
1599	}
1600}
1601EXPORT_SYMBOL(drm_atomic_helper_commit_hw_done);
1602
1603/**
1604 * drm_atomic_helper_commit_cleanup_done - signal completion of commit
1605 * @old_state: atomic state object with old state structures
1606 *
1607 * This signals completion of the atomic update @old_state, including any
1608 * cleanup work. If used, it must be called right before calling
1609 * drm_atomic_state_put().
1610 *
1611 * This is part of the atomic helper support for nonblocking commits, see
1612 * drm_atomic_helper_setup_commit() for an overview.
1613 */
1614void drm_atomic_helper_commit_cleanup_done(struct drm_atomic_state *old_state)
1615{
1616	struct drm_crtc *crtc;
1617	struct drm_crtc_state *crtc_state;
1618	struct drm_crtc_commit *commit;
1619	int i;
1620	long ret;
1621
1622	for_each_crtc_in_state(old_state, crtc, crtc_state, i) {
1623		commit = old_state->crtcs[i].commit;
1624		if (WARN_ON(!commit))
1625			continue;
1626
1627		spin_lock(&crtc->commit_lock);
1628		complete_all(&commit->cleanup_done);
1629		WARN_ON(!try_wait_for_completion(&commit->hw_done));
1630
1631		/* commit_list borrows our reference, need to remove before we
1632		 * clean up our drm_atomic_state. But only after it actually
1633		 * completed, otherwise subsequent commits won't stall properly. */
1634		if (try_wait_for_completion(&commit->flip_done))
1635			goto del_commit;
1636
1637		spin_unlock(&crtc->commit_lock);
1638
1639		/* We must wait for the vblank event to signal our completion
1640		 * before releasing our reference, since the vblank work does
1641		 * not hold a reference of its own. */
1642		ret = wait_for_completion_timeout(&commit->flip_done,
1643						  10*HZ);
1644		if (ret == 0)
1645			DRM_ERROR("[CRTC:%d:%s] flip_done timed out\n",
1646				  crtc->base.id, crtc->name);
1647
1648		spin_lock(&crtc->commit_lock);
1649del_commit:
1650		list_del(&commit->commit_entry);
1651		spin_unlock(&crtc->commit_lock);
1652	}
1653}
1654EXPORT_SYMBOL(drm_atomic_helper_commit_cleanup_done);
1655
1656/**
1657 * drm_atomic_helper_prepare_planes - prepare plane resources before commit
1658 * @dev: DRM device
1659 * @state: atomic state object with new state structures
1660 *
1661 * This function prepares plane state, specifically framebuffers, for the new
1662 * configuration. If any failure is encountered this function will call
1663 * ->cleanup_fb on any already successfully prepared framebuffer.
1664 *
1665 * Returns:
1666 * 0 on success, negative error code on failure.
1667 */
1668int drm_atomic_helper_prepare_planes(struct drm_device *dev,
1669				     struct drm_atomic_state *state)
1670{
1671	struct drm_plane *plane;
1672	struct drm_plane_state *plane_state;
1673	int ret, i, j;
1674
1675	for_each_plane_in_state(state, plane, plane_state, i) {
1676		const struct drm_plane_helper_funcs *funcs;
1677
1678		funcs = plane->helper_private;
1679
1680		if (funcs->prepare_fb) {
1681			ret = funcs->prepare_fb(plane, plane_state);
1682			if (ret)
1683				goto fail;
1684		}
1685	}
1686
1687	return 0;
1688
1689fail:
1690	for_each_plane_in_state(state, plane, plane_state, j) {
1691		const struct drm_plane_helper_funcs *funcs;
1692
1693		if (j >= i)
1694			continue;
1695
1696		funcs = plane->helper_private;
1697
1698		if (funcs->cleanup_fb)
1699			funcs->cleanup_fb(plane, plane_state);
1700	}
1701
1702	return ret;
1703}
1704EXPORT_SYMBOL(drm_atomic_helper_prepare_planes);
1705
1706static bool plane_crtc_active(const struct drm_plane_state *state)
1707{
1708	return state->crtc && state->crtc->state->active;
1709}
1710
1711/**
1712 * drm_atomic_helper_commit_planes - commit plane state
1713 * @dev: DRM device
1714 * @old_state: atomic state object with old state structures
1715 * @flags: flags for committing plane state
1716 *
1717 * This function commits the new plane state using the plane and atomic helper
1718 * functions for planes and crtcs. It assumes that the atomic state has already
1719 * been pushed into the relevant object state pointers, since this step can no
1720 * longer fail.
1721 *
1722 * It still requires the global state object @old_state to know which planes and
1723 * crtcs need to be updated though.
1724 *
1725 * Note that this function does all plane updates across all CRTCs in one step.
1726 * If the hardware can't support this approach look at
1727 * drm_atomic_helper_commit_planes_on_crtc() instead.
1728 *
1729 * Plane parameters can be updated by applications while the associated CRTC is
1730 * disabled. The DRM/KMS core will store the parameters in the plane state,
1731 * which will be available to the driver when the CRTC is turned on. As a result
1732 * most drivers don't need to be immediately notified of plane updates for a
1733 * disabled CRTC.
1734 *
1735 * Unless otherwise needed, drivers are advised to set the ACTIVE_ONLY flag in
1736 * @flags in order not to receive plane update notifications related to a
1737 * disabled CRTC. This avoids the need to manually ignore plane updates in
1738 * driver code when the driver and/or hardware can't or just don't need to deal
1739 * with updates on disabled CRTCs, for example when supporting runtime PM.
1740 *
1741 * Drivers may set the NO_DISABLE_AFTER_MODESET flag in @flags if the relevant
1742 * display controllers require to disable a CRTC's planes when the CRTC is
1743 * disabled. This function would skip the ->atomic_disable call for a plane if
1744 * the CRTC of the old plane state needs a modesetting operation. Of course,
1745 * the drivers need to disable the planes in their CRTC disable callbacks
1746 * since no one else would do that.
1747 *
1748 * The drm_atomic_helper_commit() default implementation doesn't set the
1749 * ACTIVE_ONLY flag to most closely match the behaviour of the legacy helpers.
1750 * This should not be copied blindly by drivers.
1751 */
1752void drm_atomic_helper_commit_planes(struct drm_device *dev,
1753				     struct drm_atomic_state *old_state,
1754				     uint32_t flags)
1755{
1756	struct drm_crtc *crtc;
1757	struct drm_crtc_state *old_crtc_state;
1758	struct drm_plane *plane;
1759	struct drm_plane_state *old_plane_state;
1760	int i;
1761	bool active_only = flags & DRM_PLANE_COMMIT_ACTIVE_ONLY;
1762	bool no_disable = flags & DRM_PLANE_COMMIT_NO_DISABLE_AFTER_MODESET;
1763
1764	for_each_crtc_in_state(old_state, crtc, old_crtc_state, i) {
1765		const struct drm_crtc_helper_funcs *funcs;
1766
1767		funcs = crtc->helper_private;
1768
1769		if (!funcs || !funcs->atomic_begin)
1770			continue;
1771
1772		if (active_only && !crtc->state->active)
1773			continue;
1774
1775		funcs->atomic_begin(crtc, old_crtc_state);
1776	}
1777
1778	for_each_plane_in_state(old_state, plane, old_plane_state, i) {
1779		const struct drm_plane_helper_funcs *funcs;
1780		bool disabling;
1781
1782		funcs = plane->helper_private;
1783
1784		if (!funcs)
1785			continue;
1786
1787		disabling = drm_atomic_plane_disabling(plane, old_plane_state);
1788
1789		if (active_only) {
1790			/*
1791			 * Skip planes related to inactive CRTCs. If the plane
1792			 * is enabled use the state of the current CRTC. If the
1793			 * plane is being disabled use the state of the old
1794			 * CRTC to avoid skipping planes being disabled on an
1795			 * active CRTC.
1796			 */
1797			if (!disabling && !plane_crtc_active(plane->state))
1798				continue;
1799			if (disabling && !plane_crtc_active(old_plane_state))
1800				continue;
1801		}
1802
1803		/*
1804		 * Special-case disabling the plane if drivers support it.
1805		 */
1806		if (disabling && funcs->atomic_disable) {
1807			struct drm_crtc_state *crtc_state;
1808
1809			crtc_state = old_plane_state->crtc->state;
1810
1811			if (drm_atomic_crtc_needs_modeset(crtc_state) &&
1812			    no_disable)
1813				continue;
1814
1815			funcs->atomic_disable(plane, old_plane_state);
1816		} else if (plane->state->crtc || disabling) {
1817			funcs->atomic_update(plane, old_plane_state);
1818		}
1819	}
1820
1821	for_each_crtc_in_state(old_state, crtc, old_crtc_state, i) {
1822		const struct drm_crtc_helper_funcs *funcs;
1823
1824		funcs = crtc->helper_private;
1825
1826		if (!funcs || !funcs->atomic_flush)
1827			continue;
1828
1829		if (active_only && !crtc->state->active)
1830			continue;
1831
1832		funcs->atomic_flush(crtc, old_crtc_state);
1833	}
1834}
1835EXPORT_SYMBOL(drm_atomic_helper_commit_planes);
1836
1837/**
1838 * drm_atomic_helper_commit_planes_on_crtc - commit plane state for a crtc
1839 * @old_crtc_state: atomic state object with the old crtc state
1840 *
1841 * This function commits the new plane state using the plane and atomic helper
1842 * functions for planes on the specific crtc. It assumes that the atomic state
1843 * has already been pushed into the relevant object state pointers, since this
1844 * step can no longer fail.
1845 *
1846 * This function is useful when plane updates should be done crtc-by-crtc
1847 * instead of one global step like drm_atomic_helper_commit_planes() does.
1848 *
1849 * This function can only be savely used when planes are not allowed to move
1850 * between different CRTCs because this function doesn't handle inter-CRTC
1851 * depencies. Callers need to ensure that either no such depencies exist,
1852 * resolve them through ordering of commit calls or through some other means.
1853 */
1854void
1855drm_atomic_helper_commit_planes_on_crtc(struct drm_crtc_state *old_crtc_state)
1856{
1857	const struct drm_crtc_helper_funcs *crtc_funcs;
1858	struct drm_crtc *crtc = old_crtc_state->crtc;
1859	struct drm_atomic_state *old_state = old_crtc_state->state;
1860	struct drm_plane *plane;
1861	unsigned plane_mask;
1862
1863	plane_mask = old_crtc_state->plane_mask;
1864	plane_mask |= crtc->state->plane_mask;
1865
1866	crtc_funcs = crtc->helper_private;
1867	if (crtc_funcs && crtc_funcs->atomic_begin)
1868		crtc_funcs->atomic_begin(crtc, old_crtc_state);
1869
1870	drm_for_each_plane_mask(plane, crtc->dev, plane_mask) {
1871		struct drm_plane_state *old_plane_state =
1872			drm_atomic_get_existing_plane_state(old_state, plane);
1873		const struct drm_plane_helper_funcs *plane_funcs;
1874
1875		plane_funcs = plane->helper_private;
1876
1877		if (!old_plane_state || !plane_funcs)
1878			continue;
1879
1880		WARN_ON(plane->state->crtc && plane->state->crtc != crtc);
1881
1882		if (drm_atomic_plane_disabling(plane, old_plane_state) &&
1883		    plane_funcs->atomic_disable)
1884			plane_funcs->atomic_disable(plane, old_plane_state);
1885		else if (plane->state->crtc ||
1886			 drm_atomic_plane_disabling(plane, old_plane_state))
1887			plane_funcs->atomic_update(plane, old_plane_state);
1888	}
1889
1890	if (crtc_funcs && crtc_funcs->atomic_flush)
1891		crtc_funcs->atomic_flush(crtc, old_crtc_state);
1892}
1893EXPORT_SYMBOL(drm_atomic_helper_commit_planes_on_crtc);
1894
1895/**
1896 * drm_atomic_helper_disable_planes_on_crtc - helper to disable CRTC's planes
1897 * @old_crtc_state: atomic state object with the old CRTC state
1898 * @atomic: if set, synchronize with CRTC's atomic_begin/flush hooks
1899 *
1900 * Disables all planes associated with the given CRTC. This can be
1901 * used for instance in the CRTC helper atomic_disable callback to disable
1902 * all planes.
1903 *
1904 * If the atomic-parameter is set the function calls the CRTC's
1905 * atomic_begin hook before and atomic_flush hook after disabling the
1906 * planes.
1907 *
1908 * It is a bug to call this function without having implemented the
1909 * ->atomic_disable() plane hook.
1910 */
1911void
1912drm_atomic_helper_disable_planes_on_crtc(struct drm_crtc_state *old_crtc_state,
1913					 bool atomic)
1914{
1915	struct drm_crtc *crtc = old_crtc_state->crtc;
1916	const struct drm_crtc_helper_funcs *crtc_funcs =
1917		crtc->helper_private;
1918	struct drm_plane *plane;
1919
1920	if (atomic && crtc_funcs && crtc_funcs->atomic_begin)
1921		crtc_funcs->atomic_begin(crtc, NULL);
1922
1923	drm_atomic_crtc_state_for_each_plane(plane, old_crtc_state) {
1924		const struct drm_plane_helper_funcs *plane_funcs =
1925			plane->helper_private;
1926
1927		if (!plane_funcs)
1928			continue;
1929
1930		WARN_ON(!plane_funcs->atomic_disable);
1931		if (plane_funcs->atomic_disable)
1932			plane_funcs->atomic_disable(plane, NULL);
1933	}
1934
1935	if (atomic && crtc_funcs && crtc_funcs->atomic_flush)
1936		crtc_funcs->atomic_flush(crtc, NULL);
1937}
1938EXPORT_SYMBOL(drm_atomic_helper_disable_planes_on_crtc);
1939
1940/**
1941 * drm_atomic_helper_cleanup_planes - cleanup plane resources after commit
1942 * @dev: DRM device
1943 * @old_state: atomic state object with old state structures
1944 *
1945 * This function cleans up plane state, specifically framebuffers, from the old
1946 * configuration. Hence the old configuration must be perserved in @old_state to
1947 * be able to call this function.
1948 *
1949 * This function must also be called on the new state when the atomic update
1950 * fails at any point after calling drm_atomic_helper_prepare_planes().
1951 */
1952void drm_atomic_helper_cleanup_planes(struct drm_device *dev,
1953				      struct drm_atomic_state *old_state)
1954{
1955	struct drm_plane *plane;
1956	struct drm_plane_state *plane_state;
1957	int i;
1958
1959	for_each_plane_in_state(old_state, plane, plane_state, i) {
1960		const struct drm_plane_helper_funcs *funcs;
1961
1962		funcs = plane->helper_private;
1963
1964		if (funcs->cleanup_fb)
1965			funcs->cleanup_fb(plane, plane_state);
1966	}
1967}
1968EXPORT_SYMBOL(drm_atomic_helper_cleanup_planes);
1969
1970/**
1971 * drm_atomic_helper_swap_state - store atomic state into current sw state
1972 * @state: atomic state
1973 * @stall: stall for proceeding commits
1974 *
1975 * This function stores the atomic state into the current state pointers in all
1976 * driver objects. It should be called after all failing steps have been done
1977 * and succeeded, but before the actual hardware state is committed.
1978 *
1979 * For cleanup and error recovery the current state for all changed objects will
1980 * be swaped into @state.
1981 *
1982 * With that sequence it fits perfectly into the plane prepare/cleanup sequence:
1983 *
1984 * 1. Call drm_atomic_helper_prepare_planes() with the staged atomic state.
1985 *
1986 * 2. Do any other steps that might fail.
1987 *
1988 * 3. Put the staged state into the current state pointers with this function.
1989 *
1990 * 4. Actually commit the hardware state.
1991 *
1992 * 5. Call drm_atomic_helper_cleanup_planes() with @state, which since step 3
1993 * contains the old state. Also do any other cleanup required with that state.
1994 *
1995 * @stall must be set when nonblocking commits for this driver directly access
1996 * the ->state pointer of &drm_plane, &drm_crtc or &drm_connector. With the
1997 * current atomic helpers this is almost always the case, since the helpers
1998 * don't pass the right state structures to the callbacks.
1999 */
2000void drm_atomic_helper_swap_state(struct drm_atomic_state *state,
2001				  bool stall)
2002{
2003	int i;
2004	long ret;
2005	struct drm_connector *connector;
2006	struct drm_connector_state *conn_state;
2007	struct drm_crtc *crtc;
2008	struct drm_crtc_state *crtc_state;
2009	struct drm_plane *plane;
2010	struct drm_plane_state *plane_state;
2011	struct drm_crtc_commit *commit;
2012
2013	if (stall) {
2014		for_each_crtc_in_state(state, crtc, crtc_state, i) {
2015			spin_lock(&crtc->commit_lock);
2016			commit = list_first_entry_or_null(&crtc->commit_list,
2017					struct drm_crtc_commit, commit_entry);
2018			if (commit)
2019				drm_crtc_commit_get(commit);
2020			spin_unlock(&crtc->commit_lock);
2021
2022			if (!commit)
2023				continue;
2024
2025			ret = wait_for_completion_timeout(&commit->hw_done,
2026							  10*HZ);
2027			if (ret == 0)
2028				DRM_ERROR("[CRTC:%d:%s] hw_done timed out\n",
2029					  crtc->base.id, crtc->name);
2030			drm_crtc_commit_put(commit);
2031		}
2032	}
2033
2034	for_each_connector_in_state(state, connector, conn_state, i) {
2035		connector->state->state = state;
2036		swap(state->connectors[i].state, connector->state);
2037		connector->state->state = NULL;
2038	}
2039
2040	for_each_crtc_in_state(state, crtc, crtc_state, i) {
2041		crtc->state->state = state;
2042		swap(state->crtcs[i].state, crtc->state);
2043		crtc->state->state = NULL;
2044
2045		if (state->crtcs[i].commit) {
2046			spin_lock(&crtc->commit_lock);
2047			list_add(&state->crtcs[i].commit->commit_entry,
2048				 &crtc->commit_list);
2049			spin_unlock(&crtc->commit_lock);
2050
2051			state->crtcs[i].commit->event = NULL;
2052		}
2053	}
2054
2055	for_each_plane_in_state(state, plane, plane_state, i) {
2056		plane->state->state = state;
2057		swap(state->planes[i].state, plane->state);
2058		plane->state->state = NULL;
2059	}
2060}
2061EXPORT_SYMBOL(drm_atomic_helper_swap_state);
2062
2063/**
2064 * drm_atomic_helper_update_plane - Helper for primary plane update using atomic
2065 * @plane: plane object to update
2066 * @crtc: owning CRTC of owning plane
2067 * @fb: framebuffer to flip onto plane
2068 * @crtc_x: x offset of primary plane on crtc
2069 * @crtc_y: y offset of primary plane on crtc
2070 * @crtc_w: width of primary plane rectangle on crtc
2071 * @crtc_h: height of primary plane rectangle on crtc
2072 * @src_x: x offset of @fb for panning
2073 * @src_y: y offset of @fb for panning
2074 * @src_w: width of source rectangle in @fb
2075 * @src_h: height of source rectangle in @fb
2076 *
2077 * Provides a default plane update handler using the atomic driver interface.
2078 *
2079 * RETURNS:
2080 * Zero on success, error code on failure
2081 */
2082int drm_atomic_helper_update_plane(struct drm_plane *plane,
2083				   struct drm_crtc *crtc,
2084				   struct drm_framebuffer *fb,
2085				   int crtc_x, int crtc_y,
2086				   unsigned int crtc_w, unsigned int crtc_h,
2087				   uint32_t src_x, uint32_t src_y,
2088				   uint32_t src_w, uint32_t src_h)
2089{
2090	struct drm_atomic_state *state;
2091	struct drm_plane_state *plane_state;
2092	int ret = 0;
2093
2094	state = drm_atomic_state_alloc(plane->dev);
2095	if (!state)
2096		return -ENOMEM;
2097
2098	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
2099retry:
2100	plane_state = drm_atomic_get_plane_state(state, plane);
2101	if (IS_ERR(plane_state)) {
2102		ret = PTR_ERR(plane_state);
2103		goto fail;
2104	}
2105
2106	ret = drm_atomic_set_crtc_for_plane(plane_state, crtc);
2107	if (ret != 0)
2108		goto fail;
2109	drm_atomic_set_fb_for_plane(plane_state, fb);
2110	plane_state->crtc_x = crtc_x;
2111	plane_state->crtc_y = crtc_y;
2112	plane_state->crtc_w = crtc_w;
2113	plane_state->crtc_h = crtc_h;
2114	plane_state->src_x = src_x;
2115	plane_state->src_y = src_y;
2116	plane_state->src_w = src_w;
2117	plane_state->src_h = src_h;
2118
2119	if (plane == crtc->cursor)
2120		state->legacy_cursor_update = true;
2121
2122	ret = drm_atomic_commit(state);
2123fail:
2124	if (ret == -EDEADLK)
2125		goto backoff;
2126
2127	drm_atomic_state_put(state);
2128	return ret;
2129
2130backoff:
2131	drm_atomic_state_clear(state);
2132	drm_atomic_legacy_backoff(state);
2133
2134	/*
2135	 * Someone might have exchanged the framebuffer while we dropped locks
2136	 * in the backoff code. We need to fix up the fb refcount tracking the
2137	 * core does for us.
2138	 */
2139	plane->old_fb = plane->fb;
2140
2141	goto retry;
2142}
2143EXPORT_SYMBOL(drm_atomic_helper_update_plane);
2144
2145/**
2146 * drm_atomic_helper_disable_plane - Helper for primary plane disable using * atomic
2147 * @plane: plane to disable
2148 *
2149 * Provides a default plane disable handler using the atomic driver interface.
2150 *
2151 * RETURNS:
2152 * Zero on success, error code on failure
2153 */
2154int drm_atomic_helper_disable_plane(struct drm_plane *plane)
2155{
2156	struct drm_atomic_state *state;
2157	struct drm_plane_state *plane_state;
2158	int ret = 0;
2159
2160	/*
2161	 * FIXME: Without plane->crtc set we can't get at the implicit legacy
2162	 * acquire context. The real fix will be to wire the acquire ctx through
2163	 * everywhere we need it, but meanwhile prevent chaos by just skipping
2164	 * this noop. The critical case is the cursor ioctls which a) only grab
2165	 * crtc/cursor-plane locks (so we need the crtc to get at the right
2166	 * acquire context) and b) can try to disable the plane multiple times.
2167	 */
2168	if (!plane->crtc)
2169		return 0;
2170
2171	state = drm_atomic_state_alloc(plane->dev);
2172	if (!state)
2173		return -ENOMEM;
2174
2175	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(plane->crtc);
2176retry:
2177	plane_state = drm_atomic_get_plane_state(state, plane);
2178	if (IS_ERR(plane_state)) {
2179		ret = PTR_ERR(plane_state);
2180		goto fail;
2181	}
2182
2183	if (plane_state->crtc && (plane == plane->crtc->cursor))
2184		plane_state->state->legacy_cursor_update = true;
2185
2186	ret = __drm_atomic_helper_disable_plane(plane, plane_state);
2187	if (ret != 0)
2188		goto fail;
2189
2190	ret = drm_atomic_commit(state);
2191fail:
2192	if (ret == -EDEADLK)
2193		goto backoff;
2194
2195	drm_atomic_state_put(state);
2196	return ret;
2197
2198backoff:
2199	drm_atomic_state_clear(state);
2200	drm_atomic_legacy_backoff(state);
2201
2202	/*
2203	 * Someone might have exchanged the framebuffer while we dropped locks
2204	 * in the backoff code. We need to fix up the fb refcount tracking the
2205	 * core does for us.
2206	 */
2207	plane->old_fb = plane->fb;
2208
2209	goto retry;
2210}
2211EXPORT_SYMBOL(drm_atomic_helper_disable_plane);
2212
2213/* just used from fb-helper and atomic-helper: */
2214int __drm_atomic_helper_disable_plane(struct drm_plane *plane,
2215		struct drm_plane_state *plane_state)
2216{
2217	int ret;
2218
2219	ret = drm_atomic_set_crtc_for_plane(plane_state, NULL);
2220	if (ret != 0)
2221		return ret;
2222
2223	drm_atomic_set_fb_for_plane(plane_state, NULL);
2224	plane_state->crtc_x = 0;
2225	plane_state->crtc_y = 0;
2226	plane_state->crtc_w = 0;
2227	plane_state->crtc_h = 0;
2228	plane_state->src_x = 0;
2229	plane_state->src_y = 0;
2230	plane_state->src_w = 0;
2231	plane_state->src_h = 0;
2232
2233	return 0;
2234}
2235
2236static int update_output_state(struct drm_atomic_state *state,
2237			       struct drm_mode_set *set)
2238{
2239	struct drm_device *dev = set->crtc->dev;
2240	struct drm_crtc *crtc;
2241	struct drm_crtc_state *crtc_state;
2242	struct drm_connector *connector;
2243	struct drm_connector_state *conn_state;
2244	int ret, i;
2245
2246	ret = drm_modeset_lock(&dev->mode_config.connection_mutex,
2247			       state->acquire_ctx);
2248	if (ret)
2249		return ret;
2250
2251	/* First disable all connectors on the target crtc. */
2252	ret = drm_atomic_add_affected_connectors(state, set->crtc);
2253	if (ret)
2254		return ret;
2255
2256	for_each_connector_in_state(state, connector, conn_state, i) {
2257		if (conn_state->crtc == set->crtc) {
2258			ret = drm_atomic_set_crtc_for_connector(conn_state,
2259								NULL);
2260			if (ret)
2261				return ret;
2262		}
2263	}
2264
2265	/* Then set all connectors from set->connectors on the target crtc */
2266	for (i = 0; i < set->num_connectors; i++) {
2267		conn_state = drm_atomic_get_connector_state(state,
2268							    set->connectors[i]);
2269		if (IS_ERR(conn_state))
2270			return PTR_ERR(conn_state);
2271
2272		ret = drm_atomic_set_crtc_for_connector(conn_state,
2273							set->crtc);
2274		if (ret)
2275			return ret;
2276	}
2277
2278	for_each_crtc_in_state(state, crtc, crtc_state, i) {
2279		/* Don't update ->enable for the CRTC in the set_config request,
2280		 * since a mismatch would indicate a bug in the upper layers.
2281		 * The actual modeset code later on will catch any
2282		 * inconsistencies here. */
2283		if (crtc == set->crtc)
2284			continue;
2285
2286		if (!crtc_state->connector_mask) {
2287			ret = drm_atomic_set_mode_prop_for_crtc(crtc_state,
2288								NULL);
2289			if (ret < 0)
2290				return ret;
2291
2292			crtc_state->active = false;
2293		}
2294	}
2295
2296	return 0;
2297}
2298
2299/**
2300 * drm_atomic_helper_set_config - set a new config from userspace
2301 * @set: mode set configuration
2302 *
2303 * Provides a default crtc set_config handler using the atomic driver interface.
2304 *
2305 * Returns:
2306 * Returns 0 on success, negative errno numbers on failure.
2307 */
2308int drm_atomic_helper_set_config(struct drm_mode_set *set)
2309{
2310	struct drm_atomic_state *state;
2311	struct drm_crtc *crtc = set->crtc;
2312	int ret = 0;
2313
2314	state = drm_atomic_state_alloc(crtc->dev);
2315	if (!state)
2316		return -ENOMEM;
2317
2318	state->legacy_set_config = true;
2319	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
2320retry:
2321	ret = __drm_atomic_helper_set_config(set, state);
2322	if (ret != 0)
2323		goto fail;
2324
2325	ret = drm_atomic_commit(state);
2326fail:
2327	if (ret == -EDEADLK)
2328		goto backoff;
2329
2330	drm_atomic_state_put(state);
2331	return ret;
2332
2333backoff:
2334	drm_atomic_state_clear(state);
2335	drm_atomic_legacy_backoff(state);
2336
2337	/*
2338	 * Someone might have exchanged the framebuffer while we dropped locks
2339	 * in the backoff code. We need to fix up the fb refcount tracking the
2340	 * core does for us.
2341	 */
2342	crtc->primary->old_fb = crtc->primary->fb;
2343
2344	goto retry;
2345}
2346EXPORT_SYMBOL(drm_atomic_helper_set_config);
2347
2348/* just used from fb-helper and atomic-helper: */
2349int __drm_atomic_helper_set_config(struct drm_mode_set *set,
2350		struct drm_atomic_state *state)
2351{
2352	struct drm_crtc_state *crtc_state;
2353	struct drm_plane_state *primary_state;
2354	struct drm_crtc *crtc = set->crtc;
2355	int hdisplay, vdisplay;
2356	int ret;
2357
2358	crtc_state = drm_atomic_get_crtc_state(state, crtc);
2359	if (IS_ERR(crtc_state))
2360		return PTR_ERR(crtc_state);
2361
2362	primary_state = drm_atomic_get_plane_state(state, crtc->primary);
2363	if (IS_ERR(primary_state))
2364		return PTR_ERR(primary_state);
2365
2366	if (!set->mode) {
2367		WARN_ON(set->fb);
2368		WARN_ON(set->num_connectors);
2369
2370		ret = drm_atomic_set_mode_for_crtc(crtc_state, NULL);
2371		if (ret != 0)
2372			return ret;
2373
2374		crtc_state->active = false;
2375
2376		ret = drm_atomic_set_crtc_for_plane(primary_state, NULL);
2377		if (ret != 0)
2378			return ret;
2379
2380		drm_atomic_set_fb_for_plane(primary_state, NULL);
2381
2382		goto commit;
2383	}
2384
2385	WARN_ON(!set->fb);
2386	WARN_ON(!set->num_connectors);
2387
2388	ret = drm_atomic_set_mode_for_crtc(crtc_state, set->mode);
2389	if (ret != 0)
2390		return ret;
2391
2392	crtc_state->active = true;
2393
2394	ret = drm_atomic_set_crtc_for_plane(primary_state, crtc);
2395	if (ret != 0)
2396		return ret;
2397
2398	drm_crtc_get_hv_timing(set->mode, &hdisplay, &vdisplay);
2399
2400	drm_atomic_set_fb_for_plane(primary_state, set->fb);
2401	primary_state->crtc_x = 0;
2402	primary_state->crtc_y = 0;
2403	primary_state->crtc_w = hdisplay;
2404	primary_state->crtc_h = vdisplay;
2405	primary_state->src_x = set->x << 16;
2406	primary_state->src_y = set->y << 16;
2407	if (drm_rotation_90_or_270(primary_state->rotation)) {
2408		primary_state->src_w = vdisplay << 16;
2409		primary_state->src_h = hdisplay << 16;
2410	} else {
2411		primary_state->src_w = hdisplay << 16;
2412		primary_state->src_h = vdisplay << 16;
2413	}
2414
2415commit:
2416	ret = update_output_state(state, set);
2417	if (ret)
2418		return ret;
2419
2420	return 0;
2421}
2422
2423/**
2424 * drm_atomic_helper_disable_all - disable all currently active outputs
2425 * @dev: DRM device
2426 * @ctx: lock acquisition context
2427 *
2428 * Loops through all connectors, finding those that aren't turned off and then
2429 * turns them off by setting their DPMS mode to OFF and deactivating the CRTC
2430 * that they are connected to.
2431 *
2432 * This is used for example in suspend/resume to disable all currently active
2433 * functions when suspending.
2434 *
2435 * Note that if callers haven't already acquired all modeset locks this might
2436 * return -EDEADLK, which must be handled by calling drm_modeset_backoff().
2437 *
2438 * Returns:
2439 * 0 on success or a negative error code on failure.
2440 *
2441 * See also:
2442 * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
2443 */
2444int drm_atomic_helper_disable_all(struct drm_device *dev,
2445				  struct drm_modeset_acquire_ctx *ctx)
2446{
2447	struct drm_atomic_state *state;
2448	struct drm_connector *conn;
2449	int err;
2450
2451	state = drm_atomic_state_alloc(dev);
2452	if (!state)
2453		return -ENOMEM;
2454
2455	state->acquire_ctx = ctx;
2456
2457	drm_for_each_connector(conn, dev) {
2458		struct drm_crtc *crtc = conn->state->crtc;
2459		struct drm_crtc_state *crtc_state;
2460
2461		if (!crtc || conn->dpms != DRM_MODE_DPMS_ON)
2462			continue;
2463
2464		crtc_state = drm_atomic_get_crtc_state(state, crtc);
2465		if (IS_ERR(crtc_state)) {
2466			err = PTR_ERR(crtc_state);
2467			goto free;
2468		}
2469
2470		crtc_state->active = false;
2471	}
2472
2473	err = drm_atomic_commit(state);
2474free:
2475	drm_atomic_state_put(state);
2476	return err;
2477}
2478EXPORT_SYMBOL(drm_atomic_helper_disable_all);
2479
2480/**
2481 * drm_atomic_helper_suspend - subsystem-level suspend helper
2482 * @dev: DRM device
2483 *
2484 * Duplicates the current atomic state, disables all active outputs and then
2485 * returns a pointer to the original atomic state to the caller. Drivers can
2486 * pass this pointer to the drm_atomic_helper_resume() helper upon resume to
2487 * restore the output configuration that was active at the time the system
2488 * entered suspend.
2489 *
2490 * Note that it is potentially unsafe to use this. The atomic state object
2491 * returned by this function is assumed to be persistent. Drivers must ensure
2492 * that this holds true. Before calling this function, drivers must make sure
2493 * to suspend fbdev emulation so that nothing can be using the device.
2494 *
2495 * Returns:
2496 * A pointer to a copy of the state before suspend on success or an ERR_PTR()-
2497 * encoded error code on failure. Drivers should store the returned atomic
2498 * state object and pass it to the drm_atomic_helper_resume() helper upon
2499 * resume.
2500 *
2501 * See also:
2502 * drm_atomic_helper_duplicate_state(), drm_atomic_helper_disable_all(),
2503 * drm_atomic_helper_resume()
2504 */
2505struct drm_atomic_state *drm_atomic_helper_suspend(struct drm_device *dev)
2506{
2507	struct drm_modeset_acquire_ctx ctx;
2508	struct drm_atomic_state *state;
2509	int err;
2510
2511	drm_modeset_acquire_init(&ctx, 0);
2512
2513retry:
2514	err = drm_modeset_lock_all_ctx(dev, &ctx);
2515	if (err < 0) {
2516		state = ERR_PTR(err);
2517		goto unlock;
2518	}
2519
2520	state = drm_atomic_helper_duplicate_state(dev, &ctx);
2521	if (IS_ERR(state))
2522		goto unlock;
2523
2524	err = drm_atomic_helper_disable_all(dev, &ctx);
2525	if (err < 0) {
2526		drm_atomic_state_put(state);
2527		state = ERR_PTR(err);
2528		goto unlock;
2529	}
2530
2531unlock:
2532	if (PTR_ERR(state) == -EDEADLK) {
2533		drm_modeset_backoff(&ctx);
2534		goto retry;
2535	}
2536
2537	drm_modeset_drop_locks(&ctx);
2538	drm_modeset_acquire_fini(&ctx);
2539	return state;
2540}
2541EXPORT_SYMBOL(drm_atomic_helper_suspend);
2542
2543/**
2544 * drm_atomic_helper_resume - subsystem-level resume helper
2545 * @dev: DRM device
2546 * @state: atomic state to resume to
2547 *
2548 * Calls drm_mode_config_reset() to synchronize hardware and software states,
2549 * grabs all modeset locks and commits the atomic state object. This can be
2550 * used in conjunction with the drm_atomic_helper_suspend() helper to
2551 * implement suspend/resume for drivers that support atomic mode-setting.
2552 *
2553 * Returns:
2554 * 0 on success or a negative error code on failure.
2555 *
2556 * See also:
2557 * drm_atomic_helper_suspend()
2558 */
2559int drm_atomic_helper_resume(struct drm_device *dev,
2560			     struct drm_atomic_state *state)
2561{
2562	struct drm_mode_config *config = &dev->mode_config;
2563	int err;
2564
2565	drm_mode_config_reset(dev);
2566	drm_modeset_lock_all(dev);
2567	state->acquire_ctx = config->acquire_ctx;
2568	err = drm_atomic_commit(state);
2569	drm_modeset_unlock_all(dev);
2570
2571	return err;
2572}
2573EXPORT_SYMBOL(drm_atomic_helper_resume);
2574
2575/**
2576 * drm_atomic_helper_crtc_set_property - helper for crtc properties
2577 * @crtc: DRM crtc
2578 * @property: DRM property
2579 * @val: value of property
2580 *
2581 * Provides a default crtc set_property handler using the atomic driver
2582 * interface.
2583 *
2584 * RETURNS:
2585 * Zero on success, error code on failure
2586 */
2587int
2588drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc,
2589				    struct drm_property *property,
2590				    uint64_t val)
2591{
2592	struct drm_atomic_state *state;
2593	struct drm_crtc_state *crtc_state;
2594	int ret = 0;
2595
2596	state = drm_atomic_state_alloc(crtc->dev);
2597	if (!state)
2598		return -ENOMEM;
2599
2600	/* ->set_property is always called with all locks held. */
2601	state->acquire_ctx = crtc->dev->mode_config.acquire_ctx;
2602retry:
2603	crtc_state = drm_atomic_get_crtc_state(state, crtc);
2604	if (IS_ERR(crtc_state)) {
2605		ret = PTR_ERR(crtc_state);
2606		goto fail;
2607	}
2608
2609	ret = drm_atomic_crtc_set_property(crtc, crtc_state,
2610			property, val);
2611	if (ret)
2612		goto fail;
2613
2614	ret = drm_atomic_commit(state);
2615fail:
2616	if (ret == -EDEADLK)
2617		goto backoff;
2618
2619	drm_atomic_state_put(state);
2620	return ret;
2621
2622backoff:
2623	drm_atomic_state_clear(state);
2624	drm_atomic_legacy_backoff(state);
2625
2626	goto retry;
2627}
2628EXPORT_SYMBOL(drm_atomic_helper_crtc_set_property);
2629
2630/**
2631 * drm_atomic_helper_plane_set_property - helper for plane properties
2632 * @plane: DRM plane
2633 * @property: DRM property
2634 * @val: value of property
2635 *
2636 * Provides a default plane set_property handler using the atomic driver
2637 * interface.
2638 *
2639 * RETURNS:
2640 * Zero on success, error code on failure
2641 */
2642int
2643drm_atomic_helper_plane_set_property(struct drm_plane *plane,
2644				    struct drm_property *property,
2645				    uint64_t val)
2646{
2647	struct drm_atomic_state *state;
2648	struct drm_plane_state *plane_state;
2649	int ret = 0;
2650
2651	state = drm_atomic_state_alloc(plane->dev);
2652	if (!state)
2653		return -ENOMEM;
2654
2655	/* ->set_property is always called with all locks held. */
2656	state->acquire_ctx = plane->dev->mode_config.acquire_ctx;
2657retry:
2658	plane_state = drm_atomic_get_plane_state(state, plane);
2659	if (IS_ERR(plane_state)) {
2660		ret = PTR_ERR(plane_state);
2661		goto fail;
2662	}
2663
2664	ret = drm_atomic_plane_set_property(plane, plane_state,
2665			property, val);
2666	if (ret)
2667		goto fail;
2668
2669	ret = drm_atomic_commit(state);
2670fail:
2671	if (ret == -EDEADLK)
2672		goto backoff;
2673
2674	drm_atomic_state_put(state);
2675	return ret;
2676
2677backoff:
2678	drm_atomic_state_clear(state);
2679	drm_atomic_legacy_backoff(state);
2680
2681	goto retry;
2682}
2683EXPORT_SYMBOL(drm_atomic_helper_plane_set_property);
2684
2685/**
2686 * drm_atomic_helper_connector_set_property - helper for connector properties
2687 * @connector: DRM connector
2688 * @property: DRM property
2689 * @val: value of property
2690 *
2691 * Provides a default connector set_property handler using the atomic driver
2692 * interface.
2693 *
2694 * RETURNS:
2695 * Zero on success, error code on failure
2696 */
2697int
2698drm_atomic_helper_connector_set_property(struct drm_connector *connector,
2699				    struct drm_property *property,
2700				    uint64_t val)
2701{
2702	struct drm_atomic_state *state;
2703	struct drm_connector_state *connector_state;
2704	int ret = 0;
2705
2706	state = drm_atomic_state_alloc(connector->dev);
2707	if (!state)
2708		return -ENOMEM;
2709
2710	/* ->set_property is always called with all locks held. */
2711	state->acquire_ctx = connector->dev->mode_config.acquire_ctx;
2712retry:
2713	connector_state = drm_atomic_get_connector_state(state, connector);
2714	if (IS_ERR(connector_state)) {
2715		ret = PTR_ERR(connector_state);
2716		goto fail;
2717	}
2718
2719	ret = drm_atomic_connector_set_property(connector, connector_state,
2720			property, val);
2721	if (ret)
2722		goto fail;
2723
2724	ret = drm_atomic_commit(state);
2725fail:
2726	if (ret == -EDEADLK)
2727		goto backoff;
2728
2729	drm_atomic_state_put(state);
2730	return ret;
2731
2732backoff:
2733	drm_atomic_state_clear(state);
2734	drm_atomic_legacy_backoff(state);
2735
2736	goto retry;
2737}
2738EXPORT_SYMBOL(drm_atomic_helper_connector_set_property);
2739
2740/**
2741 * drm_atomic_helper_page_flip - execute a legacy page flip
2742 * @crtc: DRM crtc
2743 * @fb: DRM framebuffer
2744 * @event: optional DRM event to signal upon completion
2745 * @flags: flip flags for non-vblank sync'ed updates
2746 *
2747 * Provides a default page flip implementation using the atomic driver interface.
2748 *
2749 * Note that for now so called async page flips (i.e. updates which are not
2750 * synchronized to vblank) are not supported, since the atomic interfaces have
2751 * no provisions for this yet.
2752 *
2753 * Returns:
2754 * Returns 0 on success, negative errno numbers on failure.
2755 */
2756int drm_atomic_helper_page_flip(struct drm_crtc *crtc,
2757				struct drm_framebuffer *fb,
2758				struct drm_pending_vblank_event *event,
2759				uint32_t flags)
2760{
2761	struct drm_plane *plane = crtc->primary;
2762	struct drm_atomic_state *state;
2763	struct drm_plane_state *plane_state;
2764	struct drm_crtc_state *crtc_state;
2765	int ret = 0;
2766
2767	if (flags & DRM_MODE_PAGE_FLIP_ASYNC)
2768		return -EINVAL;
2769
2770	state = drm_atomic_state_alloc(plane->dev);
2771	if (!state)
2772		return -ENOMEM;
2773
2774	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
2775retry:
2776	crtc_state = drm_atomic_get_crtc_state(state, crtc);
2777	if (IS_ERR(crtc_state)) {
2778		ret = PTR_ERR(crtc_state);
2779		goto fail;
2780	}
2781	crtc_state->event = event;
2782
2783	plane_state = drm_atomic_get_plane_state(state, plane);
2784	if (IS_ERR(plane_state)) {
2785		ret = PTR_ERR(plane_state);
2786		goto fail;
2787	}
2788
2789	ret = drm_atomic_set_crtc_for_plane(plane_state, crtc);
2790	if (ret != 0)
2791		goto fail;
2792	drm_atomic_set_fb_for_plane(plane_state, fb);
2793
2794	/* Make sure we don't accidentally do a full modeset. */
2795	state->allow_modeset = false;
2796	if (!crtc_state->active) {
2797		DRM_DEBUG_ATOMIC("[CRTC:%d] disabled, rejecting legacy flip\n",
2798				 crtc->base.id);
2799		ret = -EINVAL;
2800		goto fail;
2801	}
2802
2803	ret = drm_atomic_nonblocking_commit(state);
2804fail:
2805	if (ret == -EDEADLK)
2806		goto backoff;
2807
2808	drm_atomic_state_put(state);
2809	return ret;
2810
2811backoff:
2812	drm_atomic_state_clear(state);
2813	drm_atomic_legacy_backoff(state);
2814
2815	/*
2816	 * Someone might have exchanged the framebuffer while we dropped locks
2817	 * in the backoff code. We need to fix up the fb refcount tracking the
2818	 * core does for us.
2819	 */
2820	plane->old_fb = plane->fb;
2821
2822	goto retry;
2823}
2824EXPORT_SYMBOL(drm_atomic_helper_page_flip);
2825
2826/**
2827 * drm_atomic_helper_connector_dpms() - connector dpms helper implementation
2828 * @connector: affected connector
2829 * @mode: DPMS mode
2830 *
2831 * This is the main helper function provided by the atomic helper framework for
2832 * implementing the legacy DPMS connector interface. It computes the new desired
2833 * ->active state for the corresponding CRTC (if the connector is enabled) and
2834 * updates it.
2835 *
2836 * Returns:
2837 * Returns 0 on success, negative errno numbers on failure.
2838 */
2839int drm_atomic_helper_connector_dpms(struct drm_connector *connector,
2840				     int mode)
2841{
2842	struct drm_mode_config *config = &connector->dev->mode_config;
2843	struct drm_atomic_state *state;
2844	struct drm_crtc_state *crtc_state;
2845	struct drm_crtc *crtc;
2846	struct drm_connector *tmp_connector;
2847	int ret;
2848	bool active = false;
2849	int old_mode = connector->dpms;
2850
2851	if (mode != DRM_MODE_DPMS_ON)
2852		mode = DRM_MODE_DPMS_OFF;
2853
2854	connector->dpms = mode;
2855	crtc = connector->state->crtc;
2856
2857	if (!crtc)
2858		return 0;
2859
2860	state = drm_atomic_state_alloc(connector->dev);
2861	if (!state)
2862		return -ENOMEM;
2863
2864	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
2865retry:
2866	crtc_state = drm_atomic_get_crtc_state(state, crtc);
2867	if (IS_ERR(crtc_state)) {
2868		ret = PTR_ERR(crtc_state);
2869		goto fail;
2870	}
2871
2872	WARN_ON(!drm_modeset_is_locked(&config->connection_mutex));
2873
2874	drm_for_each_connector(tmp_connector, connector->dev) {
2875		if (tmp_connector->state->crtc != crtc)
2876			continue;
2877
2878		if (tmp_connector->dpms == DRM_MODE_DPMS_ON) {
2879			active = true;
2880			break;
2881		}
2882	}
2883	crtc_state->active = active;
2884
2885	ret = drm_atomic_commit(state);
2886fail:
2887	if (ret == -EDEADLK)
2888		goto backoff;
2889	if (ret != 0)
2890		connector->dpms = old_mode;
2891	drm_atomic_state_put(state);
2892	return ret;
2893
2894backoff:
2895	drm_atomic_state_clear(state);
2896	drm_atomic_legacy_backoff(state);
2897
2898	goto retry;
2899}
2900EXPORT_SYMBOL(drm_atomic_helper_connector_dpms);
2901
2902/**
2903 * drm_atomic_helper_best_encoder - Helper for &drm_connector_helper_funcs
2904 *                                  ->best_encoder callback
2905 * @connector: Connector control structure
2906 *
2907 * This is a &drm_connector_helper_funcs ->best_encoder callback helper for
2908 * connectors that support exactly 1 encoder, statically determined at driver
2909 * init time.
2910 */
2911struct drm_encoder *
2912drm_atomic_helper_best_encoder(struct drm_connector *connector)
2913{
2914	WARN_ON(connector->encoder_ids[1]);
2915	return drm_encoder_find(connector->dev, connector->encoder_ids[0]);
2916}
2917EXPORT_SYMBOL(drm_atomic_helper_best_encoder);
2918
2919/**
2920 * DOC: atomic state reset and initialization
2921 *
2922 * Both the drm core and the atomic helpers assume that there is always the full
2923 * and correct atomic software state for all connectors, CRTCs and planes
2924 * available. Which is a bit a problem on driver load and also after system
2925 * suspend. One way to solve this is to have a hardware state read-out
2926 * infrastructure which reconstructs the full software state (e.g. the i915
2927 * driver).
2928 *
2929 * The simpler solution is to just reset the software state to everything off,
2930 * which is easiest to do by calling drm_mode_config_reset(). To facilitate this
2931 * the atomic helpers provide default reset implementations for all hooks.
2932 *
2933 * On the upside the precise state tracking of atomic simplifies system suspend
2934 * and resume a lot. For drivers using drm_mode_config_reset() a complete recipe
2935 * is implemented in drm_atomic_helper_suspend() and drm_atomic_helper_resume().
2936 * For other drivers the building blocks are split out, see the documentation
2937 * for these functions.
2938 */
2939
2940/**
2941 * drm_atomic_helper_crtc_reset - default ->reset hook for CRTCs
2942 * @crtc: drm CRTC
2943 *
2944 * Resets the atomic state for @crtc by freeing the state pointer (which might
2945 * be NULL, e.g. at driver load time) and allocating a new empty state object.
2946 */
2947void drm_atomic_helper_crtc_reset(struct drm_crtc *crtc)
2948{
2949	if (crtc->state)
2950		__drm_atomic_helper_crtc_destroy_state(crtc->state);
2951
2952	kfree(crtc->state);
2953	crtc->state = kzalloc(sizeof(*crtc->state), GFP_KERNEL);
2954
2955	if (crtc->state)
2956		crtc->state->crtc = crtc;
2957}
2958EXPORT_SYMBOL(drm_atomic_helper_crtc_reset);
2959
2960/**
2961 * __drm_atomic_helper_crtc_duplicate_state - copy atomic CRTC state
2962 * @crtc: CRTC object
2963 * @state: atomic CRTC state
2964 *
2965 * Copies atomic state from a CRTC's current state and resets inferred values.
2966 * This is useful for drivers that subclass the CRTC state.
2967 */
2968void __drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc,
2969					      struct drm_crtc_state *state)
2970{
2971	memcpy(state, crtc->state, sizeof(*state));
2972
2973	if (state->mode_blob)
2974		drm_property_reference_blob(state->mode_blob);
2975	if (state->degamma_lut)
2976		drm_property_reference_blob(state->degamma_lut);
2977	if (state->ctm)
2978		drm_property_reference_blob(state->ctm);
2979	if (state->gamma_lut)
2980		drm_property_reference_blob(state->gamma_lut);
2981	state->mode_changed = false;
2982	state->active_changed = false;
2983	state->planes_changed = false;
2984	state->connectors_changed = false;
2985	state->color_mgmt_changed = false;
2986	state->zpos_changed = false;
2987	state->event = NULL;
2988}
2989EXPORT_SYMBOL(__drm_atomic_helper_crtc_duplicate_state);
2990
2991/**
2992 * drm_atomic_helper_crtc_duplicate_state - default state duplicate hook
2993 * @crtc: drm CRTC
2994 *
2995 * Default CRTC state duplicate hook for drivers which don't have their own
2996 * subclassed CRTC state structure.
2997 */
2998struct drm_crtc_state *
2999drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc)
3000{
3001	struct drm_crtc_state *state;
3002
3003	if (WARN_ON(!crtc->state))
3004		return NULL;
3005
3006	state = kmalloc(sizeof(*state), GFP_KERNEL);
3007	if (state)
3008		__drm_atomic_helper_crtc_duplicate_state(crtc, state);
3009
3010	return state;
3011}
3012EXPORT_SYMBOL(drm_atomic_helper_crtc_duplicate_state);
3013
3014/**
3015 * __drm_atomic_helper_crtc_destroy_state - release CRTC state
3016 * @state: CRTC state object to release
3017 *
3018 * Releases all resources stored in the CRTC state without actually freeing
3019 * the memory of the CRTC state. This is useful for drivers that subclass the
3020 * CRTC state.
3021 */
3022void __drm_atomic_helper_crtc_destroy_state(struct drm_crtc_state *state)
3023{
3024	drm_property_unreference_blob(state->mode_blob);
3025	drm_property_unreference_blob(state->degamma_lut);
3026	drm_property_unreference_blob(state->ctm);
3027	drm_property_unreference_blob(state->gamma_lut);
3028}
3029EXPORT_SYMBOL(__drm_atomic_helper_crtc_destroy_state);
3030
3031/**
3032 * drm_atomic_helper_crtc_destroy_state - default state destroy hook
3033 * @crtc: drm CRTC
3034 * @state: CRTC state object to release
3035 *
3036 * Default CRTC state destroy hook for drivers which don't have their own
3037 * subclassed CRTC state structure.
3038 */
3039void drm_atomic_helper_crtc_destroy_state(struct drm_crtc *crtc,
3040					  struct drm_crtc_state *state)
3041{
3042	__drm_atomic_helper_crtc_destroy_state(state);
3043	kfree(state);
3044}
3045EXPORT_SYMBOL(drm_atomic_helper_crtc_destroy_state);
3046
3047/**
3048 * drm_atomic_helper_plane_reset - default ->reset hook for planes
3049 * @plane: drm plane
3050 *
3051 * Resets the atomic state for @plane by freeing the state pointer (which might
3052 * be NULL, e.g. at driver load time) and allocating a new empty state object.
3053 */
3054void drm_atomic_helper_plane_reset(struct drm_plane *plane)
3055{
3056	if (plane->state)
3057		__drm_atomic_helper_plane_destroy_state(plane->state);
3058
3059	kfree(plane->state);
3060	plane->state = kzalloc(sizeof(*plane->state), GFP_KERNEL);
3061
3062	if (plane->state) {
3063		plane->state->plane = plane;
3064		plane->state->rotation = DRM_ROTATE_0;
3065	}
3066}
3067EXPORT_SYMBOL(drm_atomic_helper_plane_reset);
3068
3069/**
3070 * __drm_atomic_helper_plane_duplicate_state - copy atomic plane state
3071 * @plane: plane object
3072 * @state: atomic plane state
3073 *
3074 * Copies atomic state from a plane's current state. This is useful for
3075 * drivers that subclass the plane state.
3076 */
3077void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,
3078					       struct drm_plane_state *state)
3079{
3080	memcpy(state, plane->state, sizeof(*state));
3081
3082	if (state->fb)
3083		drm_framebuffer_reference(state->fb);
3084
3085	state->fence = NULL;
3086}
3087EXPORT_SYMBOL(__drm_atomic_helper_plane_duplicate_state);
3088
3089/**
3090 * drm_atomic_helper_plane_duplicate_state - default state duplicate hook
3091 * @plane: drm plane
3092 *
3093 * Default plane state duplicate hook for drivers which don't have their own
3094 * subclassed plane state structure.
3095 */
3096struct drm_plane_state *
3097drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane)
3098{
3099	struct drm_plane_state *state;
3100
3101	if (WARN_ON(!plane->state))
3102		return NULL;
3103
3104	state = kmalloc(sizeof(*state), GFP_KERNEL);
3105	if (state)
3106		__drm_atomic_helper_plane_duplicate_state(plane, state);
3107
3108	return state;
3109}
3110EXPORT_SYMBOL(drm_atomic_helper_plane_duplicate_state);
3111
3112/**
3113 * __drm_atomic_helper_plane_destroy_state - release plane state
3114 * @state: plane state object to release
3115 *
3116 * Releases all resources stored in the plane state without actually freeing
3117 * the memory of the plane state. This is useful for drivers that subclass the
3118 * plane state.
3119 */
3120void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state)
3121{
3122	if (state->fb)
3123		drm_framebuffer_unreference(state->fb);
3124
3125	if (state->fence)
3126		dma_fence_put(state->fence);
3127}
3128EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);
3129
3130/**
3131 * drm_atomic_helper_plane_destroy_state - default state destroy hook
3132 * @plane: drm plane
3133 * @state: plane state object to release
3134 *
3135 * Default plane state destroy hook for drivers which don't have their own
3136 * subclassed plane state structure.
3137 */
3138void drm_atomic_helper_plane_destroy_state(struct drm_plane *plane,
3139					   struct drm_plane_state *state)
3140{
3141	__drm_atomic_helper_plane_destroy_state(state);
3142	kfree(state);
3143}
3144EXPORT_SYMBOL(drm_atomic_helper_plane_destroy_state);
3145
3146/**
3147 * __drm_atomic_helper_connector_reset - reset state on connector
3148 * @connector: drm connector
3149 * @conn_state: connector state to assign
3150 *
3151 * Initializes the newly allocated @conn_state and assigns it to
3152 * #connector ->state, usually required when initializing the drivers
3153 * or when called from the ->reset hook.
3154 *
3155 * This is useful for drivers that subclass the connector state.
3156 */
3157void
3158__drm_atomic_helper_connector_reset(struct drm_connector *connector,
3159				    struct drm_connector_state *conn_state)
3160{
3161	if (conn_state)
3162		conn_state->connector = connector;
3163
3164	connector->state = conn_state;
3165}
3166EXPORT_SYMBOL(__drm_atomic_helper_connector_reset);
3167
3168/**
3169 * drm_atomic_helper_connector_reset - default ->reset hook for connectors
3170 * @connector: drm connector
3171 *
3172 * Resets the atomic state for @connector by freeing the state pointer (which
3173 * might be NULL, e.g. at driver load time) and allocating a new empty state
3174 * object.
3175 */
3176void drm_atomic_helper_connector_reset(struct drm_connector *connector)
3177{
3178	struct drm_connector_state *conn_state =
3179		kzalloc(sizeof(*conn_state), GFP_KERNEL);
3180
3181	if (connector->state)
3182		__drm_atomic_helper_connector_destroy_state(connector->state);
3183
3184	kfree(connector->state);
3185	__drm_atomic_helper_connector_reset(connector, conn_state);
3186}
3187EXPORT_SYMBOL(drm_atomic_helper_connector_reset);
3188
3189/**
3190 * __drm_atomic_helper_connector_duplicate_state - copy atomic connector state
3191 * @connector: connector object
3192 * @state: atomic connector state
3193 *
3194 * Copies atomic state from a connector's current state. This is useful for
3195 * drivers that subclass the connector state.
3196 */
3197void
3198__drm_atomic_helper_connector_duplicate_state(struct drm_connector *connector,
3199					    struct drm_connector_state *state)
3200{
3201	memcpy(state, connector->state, sizeof(*state));
3202	if (state->crtc)
3203		drm_connector_reference(connector);
3204}
3205EXPORT_SYMBOL(__drm_atomic_helper_connector_duplicate_state);
3206
3207/**
3208 * drm_atomic_helper_connector_duplicate_state - default state duplicate hook
3209 * @connector: drm connector
3210 *
3211 * Default connector state duplicate hook for drivers which don't have their own
3212 * subclassed connector state structure.
3213 */
3214struct drm_connector_state *
3215drm_atomic_helper_connector_duplicate_state(struct drm_connector *connector)
3216{
3217	struct drm_connector_state *state;
3218
3219	if (WARN_ON(!connector->state))
3220		return NULL;
3221
3222	state = kmalloc(sizeof(*state), GFP_KERNEL);
3223	if (state)
3224		__drm_atomic_helper_connector_duplicate_state(connector, state);
3225
3226	return state;
3227}
3228EXPORT_SYMBOL(drm_atomic_helper_connector_duplicate_state);
3229
3230/**
3231 * drm_atomic_helper_duplicate_state - duplicate an atomic state object
3232 * @dev: DRM device
3233 * @ctx: lock acquisition context
3234 *
3235 * Makes a copy of the current atomic state by looping over all objects and
3236 * duplicating their respective states. This is used for example by suspend/
3237 * resume support code to save the state prior to suspend such that it can
3238 * be restored upon resume.
3239 *
3240 * Note that this treats atomic state as persistent between save and restore.
3241 * Drivers must make sure that this is possible and won't result in confusion
3242 * or erroneous behaviour.
3243 *
3244 * Note that if callers haven't already acquired all modeset locks this might
3245 * return -EDEADLK, which must be handled by calling drm_modeset_backoff().
3246 *
3247 * Returns:
3248 * A pointer to the copy of the atomic state object on success or an
3249 * ERR_PTR()-encoded error code on failure.
3250 *
3251 * See also:
3252 * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
3253 */
3254struct drm_atomic_state *
3255drm_atomic_helper_duplicate_state(struct drm_device *dev,
3256				  struct drm_modeset_acquire_ctx *ctx)
3257{
3258	struct drm_atomic_state *state;
3259	struct drm_connector *conn;
3260	struct drm_plane *plane;
3261	struct drm_crtc *crtc;
3262	int err = 0;
3263
3264	state = drm_atomic_state_alloc(dev);
3265	if (!state)
3266		return ERR_PTR(-ENOMEM);
3267
3268	state->acquire_ctx = ctx;
3269
3270	drm_for_each_crtc(crtc, dev) {
3271		struct drm_crtc_state *crtc_state;
3272
3273		crtc_state = drm_atomic_get_crtc_state(state, crtc);
3274		if (IS_ERR(crtc_state)) {
3275			err = PTR_ERR(crtc_state);
3276			goto free;
3277		}
3278	}
3279
3280	drm_for_each_plane(plane, dev) {
3281		struct drm_plane_state *plane_state;
3282
3283		plane_state = drm_atomic_get_plane_state(state, plane);
3284		if (IS_ERR(plane_state)) {
3285			err = PTR_ERR(plane_state);
3286			goto free;
3287		}
3288	}
3289
3290	drm_for_each_connector(conn, dev) {
3291		struct drm_connector_state *conn_state;
3292
3293		conn_state = drm_atomic_get_connector_state(state, conn);
3294		if (IS_ERR(conn_state)) {
3295			err = PTR_ERR(conn_state);
3296			goto free;
3297		}
3298	}
3299
3300	/* clear the acquire context so that it isn't accidentally reused */
3301	state->acquire_ctx = NULL;
3302
3303free:
3304	if (err < 0) {
3305		drm_atomic_state_put(state);
3306		state = ERR_PTR(err);
3307	}
3308
3309	return state;
3310}
3311EXPORT_SYMBOL(drm_atomic_helper_duplicate_state);
3312
3313/**
3314 * __drm_atomic_helper_connector_destroy_state - release connector state
3315 * @state: connector state object to release
3316 *
3317 * Releases all resources stored in the connector state without actually
3318 * freeing the memory of the connector state. This is useful for drivers that
3319 * subclass the connector state.
3320 */
3321void
3322__drm_atomic_helper_connector_destroy_state(struct drm_connector_state *state)
3323{
3324	/*
3325	 * This is currently a placeholder so that drivers that subclass the
3326	 * state will automatically do the right thing if code is ever added
3327	 * to this function.
3328	 */
3329	if (state->crtc)
3330		drm_connector_unreference(state->connector);
3331}
3332EXPORT_SYMBOL(__drm_atomic_helper_connector_destroy_state);
3333
3334/**
3335 * drm_atomic_helper_connector_destroy_state - default state destroy hook
3336 * @connector: drm connector
3337 * @state: connector state object to release
3338 *
3339 * Default connector state destroy hook for drivers which don't have their own
3340 * subclassed connector state structure.
3341 */
3342void drm_atomic_helper_connector_destroy_state(struct drm_connector *connector,
3343					  struct drm_connector_state *state)
3344{
3345	__drm_atomic_helper_connector_destroy_state(state);
3346	kfree(state);
3347}
3348EXPORT_SYMBOL(drm_atomic_helper_connector_destroy_state);
3349
3350/**
3351 * drm_atomic_helper_legacy_gamma_set - set the legacy gamma correction table
3352 * @crtc: CRTC object
3353 * @red: red correction table
3354 * @green: green correction table
3355 * @blue: green correction table
3356 * @size: size of the tables
3357 *
3358 * Implements support for legacy gamma correction table for drivers
3359 * that support color management through the DEGAMMA_LUT/GAMMA_LUT
3360 * properties.
3361 */
3362int drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc,
3363				       u16 *red, u16 *green, u16 *blue,
3364				       uint32_t size)
3365{
3366	struct drm_device *dev = crtc->dev;
3367	struct drm_mode_config *config = &dev->mode_config;
3368	struct drm_atomic_state *state;
3369	struct drm_crtc_state *crtc_state;
3370	struct drm_property_blob *blob = NULL;
3371	struct drm_color_lut *blob_data;
3372	int i, ret = 0;
3373
3374	state = drm_atomic_state_alloc(crtc->dev);
3375	if (!state)
3376		return -ENOMEM;
3377
3378	blob = drm_property_create_blob(dev,
3379					sizeof(struct drm_color_lut) * size,
3380					NULL);
3381	if (IS_ERR(blob)) {
3382		ret = PTR_ERR(blob);
3383		blob = NULL;
3384		goto fail;
3385	}
3386
3387	/* Prepare GAMMA_LUT with the legacy values. */
3388	blob_data = (struct drm_color_lut *) blob->data;
3389	for (i = 0; i < size; i++) {
3390		blob_data[i].red = red[i];
3391		blob_data[i].green = green[i];
3392		blob_data[i].blue = blue[i];
3393	}
3394
3395	state->acquire_ctx = crtc->dev->mode_config.acquire_ctx;
3396retry:
3397	crtc_state = drm_atomic_get_crtc_state(state, crtc);
3398	if (IS_ERR(crtc_state)) {
3399		ret = PTR_ERR(crtc_state);
3400		goto fail;
3401	}
3402
3403	/* Reset DEGAMMA_LUT and CTM properties. */
3404	ret = drm_atomic_crtc_set_property(crtc, crtc_state,
3405			config->degamma_lut_property, 0);
3406	if (ret)
3407		goto fail;
3408
3409	ret = drm_atomic_crtc_set_property(crtc, crtc_state,
3410			config->ctm_property, 0);
3411	if (ret)
3412		goto fail;
3413
3414	ret = drm_atomic_crtc_set_property(crtc, crtc_state,
3415			config->gamma_lut_property, blob->base.id);
3416	if (ret)
3417		goto fail;
3418
3419	ret = drm_atomic_commit(state);
3420fail:
3421	if (ret == -EDEADLK)
3422		goto backoff;
3423
3424	drm_atomic_state_put(state);
3425	drm_property_unreference_blob(blob);
3426	return ret;
3427
3428backoff:
3429	drm_atomic_state_clear(state);
3430	drm_atomic_legacy_backoff(state);
3431
3432	goto retry;
3433}
3434EXPORT_SYMBOL(drm_atomic_helper_legacy_gamma_set);