drivers/gpu/drm/drm_crtc_helper.c

   1 /*
   2  * Copyright (c) 2006-2008 Intel Corporation
   3  * Copyright (c) 2007 Dave Airlie <[email protected]>
   4  *
   5  * DRM core CRTC related functions
   6  *
   7  * Permission to use, copy, modify, distribute, and sell this software and its
   8  * documentation for any purpose is hereby granted without fee, provided that
   9  * the above copyright notice appear in all copies and that both that copyright
  10  * notice and this permission notice appear in supporting documentation, and
  11  * that the name of the copyright holders not be used in advertising or
  12  * publicity pertaining to distribution of the software without specific,
  13  * written prior permission.  The copyright holders make no representations
  14  * about the suitability of this software for any purpose.  It is provided "as
  15  * is" without express or implied warranty.
  16  *
  17  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  18  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  19  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  20  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  21  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  22  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  23  * OF THIS SOFTWARE.
  24  *
  25  * Authors:
  26  *      Keith Packard
  27  *      Eric Anholt <[email protected]>
  28  *      Dave Airlie <[email protected]>
  29  *      Jesse Barnes <[email protected]>
  30  */
  31
  32 #include <linux/kernel.h>
  33 #include <linux/export.h>
  34 #include <linux/moduleparam.h>
  35
  36 #include <drm/drmP.h>
  37 #include <drm/drm_atomic.h>
  38 #include <drm/drm_crtc.h>
  39 #include <drm/drm_encoder.h>
  40 #include <drm/drm_fourcc.h>
  41 #include <drm/drm_crtc_helper.h>
  42 #include <drm/drm_fb_helper.h>
  43 #include <drm/drm_plane_helper.h>
  44 #include <drm/drm_atomic_helper.h>
  45 #include <drm/drm_edid.h>
  46
  47 /**
  48  * DOC: overview
  49  *
  50  * The CRTC modeset helper library provides a default set_config implementation
  51  * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
  52  * the same callbacks which drivers can use to e.g. restore the modeset
  53  * configuration on resume with drm_helper_resume_force_mode().
  54  *
  55  * Note that this helper library doesn't track the current power state of CRTCs
  56  * and encoders. It can call callbacks like &drm_encoder_helper_funcs.dpms even
  57  * though the hardware is already in the desired state. This deficiency has been
  58  * fixed in the atomic helpers.
  59  *
  60  * The driver callbacks are mostly compatible with the atomic modeset helpers,
  61  * except for the handling of the primary plane: Atomic helpers require that the
  62  * primary plane is implemented as a real standalone plane and not directly tied
  63  * to the CRTC state. For easier transition this library provides functions to
  64  * implement the old semantics required by the CRTC helpers using the new plane
  65  * and atomic helper callbacks.
  66  *
  67  * Drivers are strongly urged to convert to the atomic helpers (by way of first
  68  * converting to the plane helpers). New drivers must not use these functions
  69  * but need to implement the atomic interface instead, potentially using the
  70  * atomic helpers for that.
  71  *
  72  * These legacy modeset helpers use the same function table structures as
  73  * all other modesetting helpers. See the documentation for struct
  74  * &drm_crtc_helper_funcs, &struct drm_encoder_helper_funcs and struct
  75  * &drm_connector_helper_funcs.
  76  */
  77
  78 /**
  79  * drm_helper_encoder_in_use - check if a given encoder is in use
  80  * @encoder: encoder to check
  81  *
  82  * Checks whether @encoder is with the current mode setting output configuration
  83  * in use by any connector. This doesn't mean that it is actually enabled since
  84  * the DPMS state is tracked separately.
  85  *
  86  * Returns:
  87  * True if @encoder is used, false otherwise.
  88  */
  89 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
  90 {
  91         struct drm_connector *connector;
  92         struct drm_connector_list_iter conn_iter;
  93         struct drm_device *dev = encoder->dev;
  94
  95         /*
  96          * We can expect this mutex to be locked if we are not panicking.
  97          * Locking is currently fubar in the panic handler.
  98          */
  99         if (!oops_in_progress) {
 100                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 101                 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 102         }
 103
 104
 105         drm_connector_list_iter_begin(dev, &conn_iter);
 106         drm_for_each_connector_iter(connector, &conn_iter) {
 107                 if (connector->encoder == encoder) {
 108                         drm_connector_list_iter_end(&conn_iter);
 109                         return true;
 110                 }
 111         }
 112         drm_connector_list_iter_end(&conn_iter);
 113         return false;
 114 }
 115 EXPORT_SYMBOL(drm_helper_encoder_in_use);
 116
 117 /**
 118  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 119  * @crtc: CRTC to check
 120  *
 121  * Checks whether @crtc is with the current mode setting output configuration
 122  * in use by any connector. This doesn't mean that it is actually enabled since
 123  * the DPMS state is tracked separately.
 124  *
 125  * Returns:
 126  * True if @crtc is used, false otherwise.
 127  */
 128 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 129 {
 130         struct drm_encoder *encoder;
 131         struct drm_device *dev = crtc->dev;
 132
 133         /*
 134          * We can expect this mutex to be locked if we are not panicking.
 135          * Locking is currently fubar in the panic handler.
 136          */
 137         if (!oops_in_progress)
 138                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 139
 140         drm_for_each_encoder(encoder, dev)
 141                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 142                         return true;
 143         return false;
 144 }
 145 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 146
 147 static void
 148 drm_encoder_disable(struct drm_encoder *encoder)
 149 {
 150         const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 151
 152         if (!encoder_funcs)
 153                 return;
 154
 155         drm_bridge_disable(encoder->bridge);
 156
 157         if (encoder_funcs->disable)
 158                 (*encoder_funcs->disable)(encoder);
 159         else if (encoder_funcs->dpms)
 160                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 161
 162         drm_bridge_post_disable(encoder->bridge);
 163 }
 164
 165 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 166 {
 167         struct drm_encoder *encoder;
 168         struct drm_crtc *crtc;
 169
 170         drm_warn_on_modeset_not_all_locked(dev);
 171
 172         drm_for_each_encoder(encoder, dev) {
 173                 if (!drm_helper_encoder_in_use(encoder)) {
 174                         drm_encoder_disable(encoder);
 175                         /* disconnect encoder from any connector */
 176                         encoder->crtc = NULL;
 177                 }
 178         }
 179
 180         drm_for_each_crtc(crtc, dev) {
 181                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 182                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 183                 if (!crtc->enabled) {
 184                         if (crtc_funcs->disable)
 185                                 (*crtc_funcs->disable)(crtc);
 186                         else
 187                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 188                         crtc->primary->fb = NULL;
 189                 }
 190         }
 191 }
 192
 193 /**
 194  * drm_helper_disable_unused_functions - disable unused objects
 195  * @dev: DRM device
 196  *
 197  * This function walks through the entire mode setting configuration of @dev. It
 198  * will remove any CRTC links of unused encoders and encoder links of
 199  * disconnected connectors. Then it will disable all unused encoders and CRTCs
 200  * either by calling their disable callback if available or by calling their
 201  * dpms callback with DRM_MODE_DPMS_OFF.
 202  *
 203  * NOTE:
 204  *
 205  * This function is part of the legacy modeset helper library and will cause
 206  * major confusion with atomic drivers. This is because atomic helpers guarantee
 207  * to never call ->disable() hooks on a disabled function, or ->enable() hooks
 208  * on an enabled functions. drm_helper_disable_unused_functions() on the other
 209  * hand throws such guarantees into the wind and calls disable hooks
 210  * unconditionally on unused functions.
 211  */
 212 void drm_helper_disable_unused_functions(struct drm_device *dev)
 213 {
 214         if (drm_core_check_feature(dev, DRIVER_ATOMIC))
 215                 DRM_ERROR("Called for atomic driver, this is not what you want.\n");
 216
 217         drm_modeset_lock_all(dev);
 218         __drm_helper_disable_unused_functions(dev);
 219         drm_modeset_unlock_all(dev);
 220 }
 221 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 222
 223 /*
 224  * Check the CRTC we're going to map each output to vs. its current
 225  * CRTC.  If they don't match, we have to disable the output and the CRTC
 226  * since the driver will have to re-route things.
 227  */
 228 static void
 229 drm_crtc_prepare_encoders(struct drm_device *dev)
 230 {
 231         const struct drm_encoder_helper_funcs *encoder_funcs;
 232         struct drm_encoder *encoder;
 233
 234         drm_for_each_encoder(encoder, dev) {
 235                 encoder_funcs = encoder->helper_private;
 236                 if (!encoder_funcs)
 237                         continue;
 238
 239                 /* Disable unused encoders */
 240                 if (encoder->crtc == NULL)
 241                         drm_encoder_disable(encoder);
 242                 /* Disable encoders whose CRTC is about to change */
 243                 if (encoder_funcs->get_crtc &&
 244                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
 245                         drm_encoder_disable(encoder);
 246         }
 247 }
 248
 249 /**
 250  * drm_crtc_helper_set_mode - internal helper to set a mode
 251  * @crtc: CRTC to program
 252  * @mode: mode to use
 253  * @x: horizontal offset into the surface
 254  * @y: vertical offset into the surface
 255  * @old_fb: old framebuffer, for cleanup
 256  *
 257  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 258  * to fixup or reject the mode prior to trying to set it. This is an internal
 259  * helper that drivers could e.g. use to update properties that require the
 260  * entire output pipe to be disabled and re-enabled in a new configuration. For
 261  * example for changing whether audio is enabled on a hdmi link or for changing
 262  * panel fitter or dither attributes. It is also called by the
 263  * drm_crtc_helper_set_config() helper function to drive the mode setting
 264  * sequence.
 265  *
 266  * Returns:
 267  * True if the mode was set successfully, false otherwise.
 268  */
 269 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 270                               struct drm_display_mode *mode,
 271                               int x, int y,
 272                               struct drm_framebuffer *old_fb)
 273 {
 274         struct drm_device *dev = crtc->dev;
 275         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
 276         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 277         const struct drm_encoder_helper_funcs *encoder_funcs;
 278         int saved_x, saved_y;
 279         bool saved_enabled;
 280         struct drm_encoder *encoder;
 281         bool ret = true;
 282
 283         drm_warn_on_modeset_not_all_locked(dev);
 284
 285         saved_enabled = crtc->enabled;
 286         crtc->enabled = drm_helper_crtc_in_use(crtc);
 287         if (!crtc->enabled)
 288                 return true;
 289
 290         adjusted_mode = drm_mode_duplicate(dev, mode);
 291         if (!adjusted_mode) {
 292                 crtc->enabled = saved_enabled;
 293                 return false;
 294         }
 295
 296         saved_mode = crtc->mode;
 297         saved_hwmode = crtc->hwmode;
 298         saved_x = crtc->x;
 299         saved_y = crtc->y;
 300
 301         /* Update crtc values up front so the driver can rely on them for mode
 302          * setting.
 303          */
 304         crtc->mode = *mode;
 305         crtc->x = x;
 306         crtc->y = y;
 307
 308         /* Pass our mode to the connectors and the CRTC to give them a chance to
 309          * adjust it according to limitations or connector properties, and also
 310          * a chance to reject the mode entirely.
 311          */
 312         drm_for_each_encoder(encoder, dev) {
 313
 314                 if (encoder->crtc != crtc)
 315                         continue;
 316
 317                 encoder_funcs = encoder->helper_private;
 318                 if (!encoder_funcs)
 319                         continue;
 320
 321                 ret = drm_bridge_mode_fixup(encoder->bridge,
 322                         mode, adjusted_mode);
 323                 if (!ret) {
 324                         DRM_DEBUG_KMS("Bridge fixup failed\n");
 325                         goto done;
 326                 }
 327
 328                 encoder_funcs = encoder->helper_private;
 329                 if (encoder_funcs->mode_fixup) {
 330                         if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 331                                                               adjusted_mode))) {
 332                                 DRM_DEBUG_KMS("Encoder fixup failed\n");
 333                                 goto done;
 334                         }
 335                 }
 336         }
 337
 338         if (crtc_funcs->mode_fixup) {
 339                 if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
 340                                                 adjusted_mode))) {
 341                         DRM_DEBUG_KMS("CRTC fixup failed\n");
 342                         goto done;
 343                 }
 344         }
 345         DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
 346
 347         crtc->hwmode = *adjusted_mode;
 348
 349         /* Prepare the encoders and CRTCs before setting the mode. */
 350         drm_for_each_encoder(encoder, dev) {
 351
 352                 if (encoder->crtc != crtc)
 353                         continue;
 354
 355                 encoder_funcs = encoder->helper_private;
 356                 if (!encoder_funcs)
 357                         continue;
 358
 359                 drm_bridge_disable(encoder->bridge);
 360
 361                 /* Disable the encoders as the first thing we do. */
 362                 if (encoder_funcs->prepare)
 363                         encoder_funcs->prepare(encoder);
 364
 365                 drm_bridge_post_disable(encoder->bridge);
 366         }
 367
 368         drm_crtc_prepare_encoders(dev);
 369
 370         crtc_funcs->prepare(crtc);
 371
 372         /* Set up the DPLL and any encoders state that needs to adjust or depend
 373          * on the DPLL.
 374          */
 375         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 376         if (!ret)
 377             goto done;
 378
 379         drm_for_each_encoder(encoder, dev) {
 380
 381                 if (encoder->crtc != crtc)
 382                         continue;
 383
 384                 encoder_funcs = encoder->helper_private;
 385                 if (!encoder_funcs)
 386                         continue;
 387
 388                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
 389                         encoder->base.id, encoder->name,
 390                         mode->base.id, mode->name);
 391                 if (encoder_funcs->mode_set)
 392                         encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 393
 394                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
 395         }
 396
 397         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 398         crtc_funcs->commit(crtc);
 399
 400         drm_for_each_encoder(encoder, dev) {
 401
 402                 if (encoder->crtc != crtc)
 403                         continue;
 404
 405                 encoder_funcs = encoder->helper_private;
 406                 if (!encoder_funcs)
 407                         continue;
 408
 409                 drm_bridge_pre_enable(encoder->bridge);
 410
 411                 if (encoder_funcs->commit)
 412                         encoder_funcs->commit(encoder);
 413
 414                 drm_bridge_enable(encoder->bridge);
 415         }
 416
 417         /* Calculate and store various constants which
 418          * are later needed by vblank and swap-completion
 419          * timestamping. They are derived from true hwmode.
 420          */
 421         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 422
 423         /* FIXME: add subpixel order */
 424 done:
 425         drm_mode_destroy(dev, adjusted_mode);
 426         if (!ret) {
 427                 crtc->enabled = saved_enabled;
 428                 crtc->mode = saved_mode;
 429                 crtc->hwmode = saved_hwmode;
 430                 crtc->x = saved_x;
 431                 crtc->y = saved_y;
 432         }
 433
 434         return ret;
 435 }
 436 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 437
 438 static void
 439 drm_crtc_helper_disable(struct drm_crtc *crtc)
 440 {
 441         struct drm_device *dev = crtc->dev;
 442         struct drm_connector *connector;
 443         struct drm_encoder *encoder;
 444
 445         /* Decouple all encoders and their attached connectors from this crtc */
 446         drm_for_each_encoder(encoder, dev) {
 447                 struct drm_connector_list_iter conn_iter;
 448
 449                 if (encoder->crtc != crtc)
 450                         continue;
 451
 452                 drm_connector_list_iter_begin(dev, &conn_iter);
 453                 drm_for_each_connector_iter(connector, &conn_iter) {
 454                         if (connector->encoder != encoder)
 455                                 continue;
 456
 457                         connector->encoder = NULL;
 458
 459                         /*
 460                          * drm_helper_disable_unused_functions() ought to be
 461                          * doing this, but since we've decoupled the encoder
 462                          * from the connector above, the required connection
 463                          * between them is henceforth no longer available.
 464                          */
 465                         connector->dpms = DRM_MODE_DPMS_OFF;
 466
 467                         /* we keep a reference while the encoder is bound */
 468                         drm_connector_put(connector);
 469                 }
 470                 drm_connector_list_iter_end(&conn_iter);
 471         }
 472
 473         __drm_helper_disable_unused_functions(dev);
 474 }
 475
 476 /**
 477  * drm_crtc_helper_set_config - set a new config from userspace
 478  * @set: mode set configuration
 479  * @ctx: lock acquire context, not used here
 480  *
 481  * The drm_crtc_helper_set_config() helper function implements the of
 482  * &drm_crtc_funcs.set_config callback for drivers using the legacy CRTC
 483  * helpers.
 484  *
 485  * It first tries to locate the best encoder for each connector by calling the
 486  * connector @drm_connector_helper_funcs.best_encoder helper operation.
 487  *
 488  * After locating the appropriate encoders, the helper function will call the
 489  * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
 490  * or reject it completely in which case an error will be returned to the
 491  * application. If the new configuration after mode adjustment is identical to
 492  * the current configuration the helper function will return without performing
 493  * any other operation.
 494  *
 495  * If the adjusted mode is identical to the current mode but changes to the
 496  * frame buffer need to be applied, the drm_crtc_helper_set_config() function
 497  * will call the CRTC &drm_crtc_helper_funcs.mode_set_base helper operation.
 498  *
 499  * If the adjusted mode differs from the current mode, or if the
 500  * ->mode_set_base() helper operation is not provided, the helper function
 501  * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
 502  * and ->commit() CRTC and encoder helper operations, in that order.
 503  * Alternatively it can also use the dpms and disable helper operations. For
 504  * details see &struct drm_crtc_helper_funcs and struct
 505  * &drm_encoder_helper_funcs.
 506  *
 507  * This function is deprecated.  New drivers must implement atomic modeset
 508  * support, for which this function is unsuitable. Instead drivers should use
 509  * drm_atomic_helper_set_config().
 510  *
 511  * Returns:
 512  * Returns 0 on success, negative errno numbers on failure.
 513  */
 514 int drm_crtc_helper_set_config(struct drm_mode_set *set,
 515                                struct drm_modeset_acquire_ctx *ctx)
 516 {
 517         struct drm_device *dev;
 518         struct drm_crtc **save_encoder_crtcs, *new_crtc;
 519         struct drm_encoder **save_connector_encoders, *new_encoder, *encoder;
 520         bool mode_changed = false; /* if true do a full mode set */
 521         bool fb_changed = false; /* if true and !mode_changed just do a flip */
 522         struct drm_connector *connector;
 523         struct drm_connector_list_iter conn_iter;
 524         int count = 0, ro, fail = 0;
 525         const struct drm_crtc_helper_funcs *crtc_funcs;
 526         struct drm_mode_set save_set;
 527         int ret;
 528         int i;
 529
 530         DRM_DEBUG_KMS("\n");
 531
 532         BUG_ON(!set);
 533         BUG_ON(!set->crtc);
 534         BUG_ON(!set->crtc->helper_private);
 535
 536         /* Enforce sane interface api - has been abused by the fb helper. */
 537         BUG_ON(!set->mode && set->fb);
 538         BUG_ON(set->fb && set->num_connectors == 0);
 539
 540         crtc_funcs = set->crtc->helper_private;
 541
 542         if (!set->mode)
 543                 set->fb = NULL;
 544
 545         if (set->fb) {
 546                 DRM_DEBUG_KMS("[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 547                               set->crtc->base.id, set->crtc->name,
 548                               set->fb->base.id,
 549                               (int)set->num_connectors, set->x, set->y);
 550         } else {
 551                 DRM_DEBUG_KMS("[CRTC:%d:%s] [NOFB]\n",
 552                               set->crtc->base.id, set->crtc->name);
 553                 drm_crtc_helper_disable(set->crtc);
 554                 return 0;
 555         }
 556
 557         dev = set->crtc->dev;
 558
 559         drm_warn_on_modeset_not_all_locked(dev);
 560
 561         /*
 562          * Allocate space for the backup of all (non-pointer) encoder and
 563          * connector data.
 564          */
 565         save_encoder_crtcs = kcalloc(dev->mode_config.num_encoder,
 566                                 sizeof(struct drm_crtc *), GFP_KERNEL);
 567         if (!save_encoder_crtcs)
 568                 return -ENOMEM;
 569
 570         save_connector_encoders = kcalloc(dev->mode_config.num_connector,
 571                                 sizeof(struct drm_encoder *), GFP_KERNEL);
 572         if (!save_connector_encoders) {
 573                 kfree(save_encoder_crtcs);
 574                 return -ENOMEM;
 575         }
 576
 577         /*
 578          * Copy data. Note that driver private data is not affected.
 579          * Should anything bad happen only the expected state is
 580          * restored, not the drivers personal bookkeeping.
 581          */
 582         count = 0;
 583         drm_for_each_encoder(encoder, dev) {
 584                 save_encoder_crtcs[count++] = encoder->crtc;
 585         }
 586
 587         count = 0;
 588         drm_connector_list_iter_begin(dev, &conn_iter);
 589         drm_for_each_connector_iter(connector, &conn_iter)
 590                 save_connector_encoders[count++] = connector->encoder;
 591         drm_connector_list_iter_end(&conn_iter);
 592
 593         save_set.crtc = set->crtc;
 594         save_set.mode = &set->crtc->mode;
 595         save_set.x = set->crtc->x;
 596         save_set.y = set->crtc->y;
 597         save_set.fb = set->crtc->primary->fb;
 598
 599         /* We should be able to check here if the fb has the same properties
 600          * and then just flip_or_move it */
 601         if (set->crtc->primary->fb != set->fb) {
 602                 /* If we have no fb then treat it as a full mode set */
 603                 if (set->crtc->primary->fb == NULL) {
 604                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 605                         mode_changed = true;
 606                 } else if (set->fb->format != set->crtc->primary->fb->format) {
 607                         mode_changed = true;
 608                 } else
 609                         fb_changed = true;
 610         }
 611
 612         if (set->x != set->crtc->x || set->y != set->crtc->y)
 613                 fb_changed = true;
 614
 615         if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
 616                 DRM_DEBUG_KMS("modes are different, full mode set\n");
 617                 drm_mode_debug_printmodeline(&set->crtc->mode);
 618                 drm_mode_debug_printmodeline(set->mode);
 619                 mode_changed = true;
 620         }
 621
 622         /* take a reference on all unbound connectors in set, reuse the
 623          * already taken reference for bound connectors
 624          */
 625         for (ro = 0; ro < set->num_connectors; ro++) {
 626                 if (set->connectors[ro]->encoder)
 627                         continue;
 628                 drm_connector_get(set->connectors[ro]);
 629         }
 630
 631         /* a) traverse passed in connector list and get encoders for them */
 632         count = 0;
 633         drm_connector_list_iter_begin(dev, &conn_iter);
 634         drm_for_each_connector_iter(connector, &conn_iter) {
 635                 const struct drm_connector_helper_funcs *connector_funcs =
 636                         connector->helper_private;
 637                 new_encoder = connector->encoder;
 638                 for (ro = 0; ro < set->num_connectors; ro++) {
 639                         if (set->connectors[ro] == connector) {
 640                                 new_encoder = connector_funcs->best_encoder(connector);
 641                                 /* if we can't get an encoder for a connector
 642                                    we are setting now - then fail */
 643                                 if (new_encoder == NULL)
 644                                         /* don't break so fail path works correct */
 645                                         fail = 1;
 646
 647                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
 648                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 649                                         mode_changed = true;
 650                                 }
 651
 652                                 break;
 653                         }
 654                 }
 655
 656                 if (new_encoder != connector->encoder) {
 657                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 658                         mode_changed = true;
 659                         /* If the encoder is reused for another connector, then
 660                          * the appropriate crtc will be set later.
 661                          */
 662                         if (connector->encoder)
 663                                 connector->encoder->crtc = NULL;
 664                         connector->encoder = new_encoder;
 665                 }
 666         }
 667         drm_connector_list_iter_end(&conn_iter);
 668
 669         if (fail) {
 670                 ret = -EINVAL;
 671                 goto fail;
 672         }
 673
 674         count = 0;
 675         drm_connector_list_iter_begin(dev, &conn_iter);
 676         drm_for_each_connector_iter(connector, &conn_iter) {
 677                 if (!connector->encoder)
 678                         continue;
 679
 680                 if (connector->encoder->crtc == set->crtc)
 681                         new_crtc = NULL;
 682                 else
 683                         new_crtc = connector->encoder->crtc;
 684
 685                 for (ro = 0; ro < set->num_connectors; ro++) {
 686                         if (set->connectors[ro] == connector)
 687                                 new_crtc = set->crtc;
 688                 }
 689
 690                 /* Make sure the new CRTC will work with the encoder */
 691                 if (new_crtc &&
 692                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 693                         ret = -EINVAL;
 694                         drm_connector_list_iter_end(&conn_iter);
 695                         goto fail;
 696                 }
 697                 if (new_crtc != connector->encoder->crtc) {
 698                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 699                         mode_changed = true;
 700                         connector->encoder->crtc = new_crtc;
 701                 }
 702                 if (new_crtc) {
 703                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
 704                                       connector->base.id, connector->name,
 705                                       new_crtc->base.id, new_crtc->name);
 706                 } else {
 707                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 708                                       connector->base.id, connector->name);
 709                 }
 710         }
 711         drm_connector_list_iter_end(&conn_iter);
 712
 713         /* mode_set_base is not a required function */
 714         if (fb_changed && !crtc_funcs->mode_set_base)
 715                 mode_changed = true;
 716
 717         if (mode_changed) {
 718                 if (drm_helper_crtc_in_use(set->crtc)) {
 719                         DRM_DEBUG_KMS("attempting to set mode from"
 720                                         " userspace\n");
 721                         drm_mode_debug_printmodeline(set->mode);
 722                         set->crtc->primary->fb = set->fb;
 723                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 724                                                       set->x, set->y,
 725                                                       save_set.fb)) {
 726                                 DRM_ERROR("failed to set mode on [CRTC:%d:%s]\n",
 727                                           set->crtc->base.id, set->crtc->name);
 728                                 set->crtc->primary->fb = save_set.fb;
 729                                 ret = -EINVAL;
 730                                 goto fail;
 731                         }
 732                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 733                         for (i = 0; i < set->num_connectors; i++) {
 734                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 735                                               set->connectors[i]->name);
 736                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 737                         }
 738                 }
 739                 __drm_helper_disable_unused_functions(dev);
 740         } else if (fb_changed) {
 741                 set->crtc->x = set->x;
 742                 set->crtc->y = set->y;
 743                 set->crtc->primary->fb = set->fb;
 744                 ret = crtc_funcs->mode_set_base(set->crtc,
 745                                                 set->x, set->y, save_set.fb);
 746                 if (ret != 0) {
 747                         set->crtc->x = save_set.x;
 748                         set->crtc->y = save_set.y;
 749                         set->crtc->primary->fb = save_set.fb;
 750                         goto fail;
 751                 }
 752         }
 753
 754         kfree(save_connector_encoders);
 755         kfree(save_encoder_crtcs);
 756         return 0;
 757
 758 fail:
 759         /* Restore all previous data. */
 760         count = 0;
 761         drm_for_each_encoder(encoder, dev) {
 762                 encoder->crtc = save_encoder_crtcs[count++];
 763         }
 764
 765         count = 0;
 766         drm_connector_list_iter_begin(dev, &conn_iter);
 767         drm_for_each_connector_iter(connector, &conn_iter)
 768                 connector->encoder = save_connector_encoders[count++];
 769         drm_connector_list_iter_end(&conn_iter);
 770
 771         /* after fail drop reference on all unbound connectors in set, let
 772          * bound connectors keep their reference
 773          */
 774         for (ro = 0; ro < set->num_connectors; ro++) {
 775                 if (set->connectors[ro]->encoder)
 776                         continue;
 777                 drm_connector_put(set->connectors[ro]);
 778         }
 779
 780         /* Try to restore the config */
 781         if (mode_changed &&
 782             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 783                                       save_set.y, save_set.fb))
 784                 DRM_ERROR("failed to restore config after modeset failure\n");
 785
 786         kfree(save_connector_encoders);
 787         kfree(save_encoder_crtcs);
 788         return ret;
 789 }
 790 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 791
 792 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 793 {
 794         int dpms = DRM_MODE_DPMS_OFF;
 795         struct drm_connector *connector;
 796         struct drm_connector_list_iter conn_iter;
 797         struct drm_device *dev = encoder->dev;
 798
 799         drm_connector_list_iter_begin(dev, &conn_iter);
 800         drm_for_each_connector_iter(connector, &conn_iter)
 801                 if (connector->encoder == encoder)
 802                         if (connector->dpms < dpms)
 803                                 dpms = connector->dpms;
 804         drm_connector_list_iter_end(&conn_iter);
 805
 806         return dpms;
 807 }
 808
 809 /* Helper which handles bridge ordering around encoder dpms */
 810 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 811 {
 812         struct drm_bridge *bridge = encoder->bridge;
 813         const struct drm_encoder_helper_funcs *encoder_funcs;
 814
 815         encoder_funcs = encoder->helper_private;
 816         if (!encoder_funcs)
 817                 return;
 818
 819         if (mode == DRM_MODE_DPMS_ON)
 820                 drm_bridge_pre_enable(bridge);
 821         else
 822                 drm_bridge_disable(bridge);
 823
 824         if (encoder_funcs->dpms)
 825                 encoder_funcs->dpms(encoder, mode);
 826
 827         if (mode == DRM_MODE_DPMS_ON)
 828                 drm_bridge_enable(bridge);
 829         else
 830                 drm_bridge_post_disable(bridge);
 831 }
 832
 833 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 834 {
 835         int dpms = DRM_MODE_DPMS_OFF;
 836         struct drm_connector *connector;
 837         struct drm_connector_list_iter conn_iter;
 838         struct drm_device *dev = crtc->dev;
 839
 840         drm_connector_list_iter_begin(dev, &conn_iter);
 841         drm_for_each_connector_iter(connector, &conn_iter)
 842                 if (connector->encoder && connector->encoder->crtc == crtc)
 843                         if (connector->dpms < dpms)
 844                                 dpms = connector->dpms;
 845         drm_connector_list_iter_end(&conn_iter);
 846
 847         return dpms;
 848 }
 849
 850 /**
 851  * drm_helper_connector_dpms() - connector dpms helper implementation
 852  * @connector: affected connector
 853  * @mode: DPMS mode
 854  *
 855  * The drm_helper_connector_dpms() helper function implements the
 856  * &drm_connector_funcs.dpms callback for drivers using the legacy CRTC
 857  * helpers.
 858  *
 859  * This is the main helper function provided by the CRTC helper framework for
 860  * implementing the DPMS connector attribute. It computes the new desired DPMS
 861  * state for all encoders and CRTCs in the output mesh and calls the
 862  * &drm_crtc_helper_funcs.dpms and &drm_encoder_helper_funcs.dpms callbacks
 863  * provided by the driver.
 864  *
 865  * This function is deprecated.  New drivers must implement atomic modeset
 866  * support, where DPMS is handled in the DRM core.
 867  *
 868  * Returns:
 869  * Always returns 0.
 870  */
 871 int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 872 {
 873         struct drm_encoder *encoder = connector->encoder;
 874         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 875         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 876
 877         if (mode == connector->dpms)
 878                 return 0;
 879
 880         old_dpms = connector->dpms;
 881         connector->dpms = mode;
 882
 883         if (encoder)
 884                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 885
 886         /* from off to on, do crtc then encoder */
 887         if (mode < old_dpms) {
 888                 if (crtc) {
 889                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 890                         if (crtc_funcs->dpms)
 891                                 (*crtc_funcs->dpms) (crtc,
 892                                                      drm_helper_choose_crtc_dpms(crtc));
 893                 }
 894                 if (encoder)
 895                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 896         }
 897
 898         /* from on to off, do encoder then crtc */
 899         if (mode > old_dpms) {
 900                 if (encoder)
 901                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 902                 if (crtc) {
 903                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 904                         if (crtc_funcs->dpms)
 905                                 (*crtc_funcs->dpms) (crtc,
 906                                                      drm_helper_choose_crtc_dpms(crtc));
 907                 }
 908         }
 909
 910         return 0;
 911 }
 912 EXPORT_SYMBOL(drm_helper_connector_dpms);
 913
 914 /**
 915  * drm_helper_resume_force_mode - force-restore mode setting configuration
 916  * @dev: drm_device which should be restored
 917  *
 918  * Drivers which use the mode setting helpers can use this function to
 919  * force-restore the mode setting configuration e.g. on resume or when something
 920  * else might have trampled over the hw state (like some overzealous old BIOSen
 921  * tended to do).
 922  *
 923  * This helper doesn't provide a error return value since restoring the old
 924  * config should never fail due to resource allocation issues since the driver
 925  * has successfully set the restored configuration already. Hence this should
 926  * boil down to the equivalent of a few dpms on calls, which also don't provide
 927  * an error code.
 928  *
 929  * Drivers where simply restoring an old configuration again might fail (e.g.
 930  * due to slight differences in allocating shared resources when the
 931  * configuration is restored in a different order than when userspace set it up)
 932  * need to use their own restore logic.
 933  *
 934  * This function is deprecated. New drivers should implement atomic mode-
 935  * setting and use the atomic suspend/resume helpers.
 936  *
 937  * See also:
 938  * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 939  */
 940 void drm_helper_resume_force_mode(struct drm_device *dev)
 941 {
 942         struct drm_crtc *crtc;
 943         struct drm_encoder *encoder;
 944         const struct drm_crtc_helper_funcs *crtc_funcs;
 945         int encoder_dpms;
 946         bool ret;
 947
 948         drm_modeset_lock_all(dev);
 949         drm_for_each_crtc(crtc, dev) {
 950
 951                 if (!crtc->enabled)
 952                         continue;
 953
 954                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 955                                                crtc->x, crtc->y, crtc->primary->fb);
 956
 957                 /* Restoring the old config should never fail! */
 958                 if (ret == false)
 959                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 960
 961                 /* Turn off outputs that were already powered off */
 962                 if (drm_helper_choose_crtc_dpms(crtc)) {
 963                         drm_for_each_encoder(encoder, dev) {
 964
 965                                 if(encoder->crtc != crtc)
 966                                         continue;
 967
 968                                 encoder_dpms = drm_helper_choose_encoder_dpms(
 969                                                         encoder);
 970
 971                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
 972                         }
 973
 974                         crtc_funcs = crtc->helper_private;
 975                         if (crtc_funcs->dpms)
 976                                 (*crtc_funcs->dpms) (crtc,
 977                                                      drm_helper_choose_crtc_dpms(crtc));
 978                 }
 979         }
 980
 981         /* disable the unused connectors while restoring the modesetting */
 982         __drm_helper_disable_unused_functions(dev);
 983         drm_modeset_unlock_all(dev);
 984 }
 985 EXPORT_SYMBOL(drm_helper_resume_force_mode);
 986
 987 /**
 988  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
 989  * @crtc: DRM CRTC
 990  * @mode: DRM display mode which userspace requested
 991  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
 992  * @x: x offset of the CRTC scanout area on the underlying framebuffer
 993  * @y: y offset of the CRTC scanout area on the underlying framebuffer
 994  * @old_fb: previous framebuffer
 995  *
 996  * This function implements a callback useable as the ->mode_set callback
 997  * required by the CRTC helpers. Besides the atomic plane helper functions for
 998  * the primary plane the driver must also provide the ->mode_set_nofb callback
 999  * to set up the CRTC.
1000  *
1001  * This is a transitional helper useful for converting drivers to the atomic
1002  * interfaces.
1003  */
1004 int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
1005                              struct drm_display_mode *adjusted_mode, int x, int y,
1006                              struct drm_framebuffer *old_fb)
1007 {
1008         struct drm_crtc_state *crtc_state;
1009         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
1010         int ret;
1011
1012         if (crtc->funcs->atomic_duplicate_state)
1013                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
1014         else {
1015                 if (!crtc->state)
1016                         drm_atomic_helper_crtc_reset(crtc);
1017
1018                 crtc_state = drm_atomic_helper_crtc_duplicate_state(crtc);
1019         }
1020
1021         if (!crtc_state)
1022                 return -ENOMEM;
1023
1024         crtc_state->planes_changed = true;
1025         crtc_state->mode_changed = true;
1026         ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
1027         if (ret)
1028                 goto out;
1029         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
1030
1031         if (crtc_funcs->atomic_check) {
1032                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
1033                 if (ret)
1034                         goto out;
1035         }
1036
1037         swap(crtc->state, crtc_state);
1038
1039         crtc_funcs->mode_set_nofb(crtc);
1040
1041         ret = drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
1042
1043 out:
1044         if (crtc_state) {
1045                 if (crtc->funcs->atomic_destroy_state)
1046                         crtc->funcs->atomic_destroy_state(crtc, crtc_state);
1047                 else
1048                         drm_atomic_helper_crtc_destroy_state(crtc, crtc_state);
1049         }
1050
1051         return ret;
1052 }
1053 EXPORT_SYMBOL(drm_helper_crtc_mode_set);
1054
1055 /**
1056  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
1057  * @crtc: DRM CRTC
1058  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1059  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1060  * @old_fb: previous framebuffer
1061  *
1062  * This function implements a callback useable as the ->mode_set_base used
1063  * required by the CRTC helpers. The driver must provide the atomic plane helper
1064  * functions for the primary plane.
1065  *
1066  * This is a transitional helper useful for converting drivers to the atomic
1067  * interfaces.
1068  */
1069 int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
1070                                   struct drm_framebuffer *old_fb)
1071 {
1072         struct drm_plane_state *plane_state;
1073         struct drm_plane *plane = crtc->primary;
1074
1075         if (plane->funcs->atomic_duplicate_state)
1076                 plane_state = plane->funcs->atomic_duplicate_state(plane);
1077         else {
1078                 if (!plane->state)
1079                         drm_atomic_helper_plane_reset(plane);
1080
1081                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
1082         }
1083         if (!plane_state)
1084                 return -ENOMEM;
1085         plane_state->plane = plane;
1086
1087         plane_state->crtc = crtc;
1088         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
1089         plane_state->crtc_x = 0;
1090         plane_state->crtc_y = 0;
1091         plane_state->crtc_h = crtc->mode.vdisplay;
1092         plane_state->crtc_w = crtc->mode.hdisplay;
1093         plane_state->src_x = x << 16;
1094         plane_state->src_y = y << 16;
1095         plane_state->src_h = crtc->mode.vdisplay << 16;
1096         plane_state->src_w = crtc->mode.hdisplay << 16;
1097
1098         return drm_plane_helper_commit(plane, plane_state, old_fb);
1099 }
1100 EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);