drivers/gpu/drm/drm_crtc_helper.c

   1 /*
   2  * Copyright (c) 2006-2008 Intel Corporation
   3  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
   4  *
   5  * DRM core CRTC related functions
   6  *
   7  * Permission to use, copy, modify, distribute, and sell this software and its
   8  * documentation for any purpose is hereby granted without fee, provided that
   9  * the above copyright notice appear in all copies and that both that copyright
  10  * notice and this permission notice appear in supporting documentation, and
  11  * that the name of the copyright holders not be used in advertising or
  12  * publicity pertaining to distribution of the software without specific,
  13  * written prior permission.  The copyright holders make no representations
  14  * about the suitability of this software for any purpose.  It is provided "as
  15  * is" without express or implied warranty.
  16  *
  17  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  18  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  19  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  20  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  21  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  22  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  23  * OF THIS SOFTWARE.
  24  *
  25  * Authors:
  26  *      Keith Packard
  27  *      Eric Anholt <eric@anholt.net>
  28  *      Dave Airlie <airlied@linux.ie>
  29  *      Jesse Barnes <jesse.barnes@intel.com>
  30  */
  31
  32 #include "drmP.h"
  33 #include "drm_crtc.h"
  34 #include "drm_crtc_helper.h"
  35
  36 /*
  37  * Detailed mode info for a standard 640x480@60Hz monitor
  38  */
  39 static struct drm_display_mode std_mode[] = {
  40         { DRM_MODE("640x480", DRM_MODE_TYPE_DEFAULT, 25200, 640, 656,
  41                    752, 800, 0, 480, 490, 492, 525, 0,
  42                    DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC) },
  43 };
  44
  45 /**
  46  * drm_helper_probe_connector_modes - get complete set of display modes
  47  * @dev: DRM device
  48  * @maxX: max width for modes
  49  * @maxY: max height for modes
  50  *
  51  * LOCKING:
  52  * Caller must hold mode config lock.
  53  *
  54  * Based on @dev's mode_config layout, scan all the connectors and try to detect
  55  * modes on them.  Modes will first be added to the connector's probed_modes
  56  * list, then culled (based on validity and the @maxX, @maxY parameters) and
  57  * put into the normal modes list.
  58  *
  59  * Intended to be used either at bootup time or when major configuration
  60  * changes have occurred.
  61  *
  62  * FIXME: take into account monitor limits
  63  */
  64 void drm_helper_probe_single_connector_modes(struct drm_connector *connector,
  65                                              uint32_t maxX, uint32_t maxY)
  66 {
  67         struct drm_device *dev = connector->dev;
  68         struct drm_display_mode *mode, *t;
  69         struct drm_connector_helper_funcs *connector_funcs =
  70                 connector->helper_private;
  71         int ret;
  72
  73         DRM_DEBUG("%s\n", drm_get_connector_name(connector));
  74         /* set all modes to the unverified state */
  75         list_for_each_entry_safe(mode, t, &connector->modes, head)
  76                 mode->status = MODE_UNVERIFIED;
  77
  78         connector->status = connector->funcs->detect(connector);
  79
  80         if (connector->status == connector_status_disconnected) {
  81                 DRM_DEBUG("%s is disconnected\n",
  82                           drm_get_connector_name(connector));
  83                 /* TODO set EDID to NULL */
  84                 return;
  85         }
  86
  87         ret = (*connector_funcs->get_modes)(connector);
  88
  89         if (ret) {
  90                 drm_mode_connector_list_update(connector);
  91         }
  92
  93         if (maxX && maxY)
  94                 drm_mode_validate_size(dev, &connector->modes, maxX,
  95                                        maxY, 0);
  96         list_for_each_entry_safe(mode, t, &connector->modes, head) {
  97                 if (mode->status == MODE_OK)
  98                         mode->status = connector_funcs->mode_valid(connector,
  99                                                                    mode);
 100         }
 101
 102
 103         drm_mode_prune_invalid(dev, &connector->modes, true);
 104
 105         if (list_empty(&connector->modes)) {
 106                 struct drm_display_mode *stdmode;
 107
 108                 DRM_DEBUG("No valid modes on %s\n",
 109                           drm_get_connector_name(connector));
 110
 111                 /* Should we do this here ???
 112                  * When no valid EDID modes are available we end up
 113                  * here and bailed in the past, now we add a standard
 114                  * 640x480@60Hz mode and carry on.
 115                  */
 116                 stdmode = drm_mode_duplicate(dev, &std_mode[0]);
 117                 drm_mode_probed_add(connector, stdmode);
 118                 drm_mode_list_concat(&connector->probed_modes,
 119                                      &connector->modes);
 120
 121                 DRM_DEBUG("Adding standard 640x480 @ 60Hz to %s\n",
 122                           drm_get_connector_name(connector));
 123         }
 124
 125         drm_mode_sort(&connector->modes);
 126
 127         DRM_DEBUG("Probed modes for %s\n", drm_get_connector_name(connector));
 128         list_for_each_entry_safe(mode, t, &connector->modes, head) {
 129                 mode->vrefresh = drm_mode_vrefresh(mode);
 130
 131                 drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
 132                 drm_mode_debug_printmodeline(mode);
 133         }
 134 }
 135 EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
 136
 137 void drm_helper_probe_connector_modes(struct drm_device *dev, uint32_t maxX,
 138                                       uint32_t maxY)
 139 {
 140         struct drm_connector *connector;
 141
 142         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 143                 drm_helper_probe_single_connector_modes(connector, maxX, maxY);
 144         }
 145 }
 146 EXPORT_SYMBOL(drm_helper_probe_connector_modes);
 147
 148
 149 /**
 150  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 151  * @crtc: CRTC to check
 152  *
 153  * LOCKING:
 154  * Caller must hold mode config lock.
 155  *
 156  * Walk @crtc's DRM device's mode_config and see if it's in use.
 157  *
 158  * RETURNS:
 159  * True if @crtc is part of the mode_config, false otherwise.
 160  */
 161 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 162 {
 163         struct drm_encoder *encoder;
 164         struct drm_device *dev = crtc->dev;
 165         /* FIXME: Locking around list access? */
 166         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
 167                 if (encoder->crtc == crtc)
 168                         return true;
 169         return false;
 170 }
 171 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 172
 173 /**
 174  * drm_disable_unused_functions - disable unused objects
 175  * @dev: DRM device
 176  *
 177  * LOCKING:
 178  * Caller must hold mode config lock.
 179  *
 180  * If an connector or CRTC isn't part of @dev's mode_config, it can be disabled
 181  * by calling its dpms function, which should power it off.
 182  */
 183 void drm_helper_disable_unused_functions(struct drm_device *dev)
 184 {
 185         struct drm_encoder *encoder;
 186         struct drm_encoder_helper_funcs *encoder_funcs;
 187         struct drm_crtc *crtc;
 188
 189         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 190                 encoder_funcs = encoder->helper_private;
 191                 if (!encoder->crtc)
 192                         (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 193         }
 194
 195         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 196                 struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 197                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 198                 if (!crtc->enabled) {
 199                         crtc_funcs->dpms(crtc, DRM_MODE_DPMS_OFF);
 200                         crtc->fb = NULL;
 201                 }
 202         }
 203 }
 204 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 205
 206 static struct drm_display_mode *drm_has_preferred_mode(struct drm_connector *connector, int width, int height)
 207 {
 208         struct drm_display_mode *mode;
 209
 210         list_for_each_entry(mode, &connector->modes, head) {
 211                 if (drm_mode_width(mode) > width ||
 212                     drm_mode_height(mode) > height)
 213                         continue;
 214                 if (mode->type & DRM_MODE_TYPE_PREFERRED)
 215                         return mode;
 216         }
 217         return NULL;
 218 }
 219
 220 static bool drm_connector_enabled(struct drm_connector *connector, bool strict)
 221 {
 222         bool enable;
 223
 224         if (strict) {
 225                 enable = connector->status == connector_status_connected;
 226         } else {
 227                 enable = connector->status != connector_status_disconnected;
 228         }
 229         return enable;
 230 }
 231
 232 static void drm_enable_connectors(struct drm_device *dev, bool *enabled)
 233 {
 234         bool any_enabled = false;
 235         struct drm_connector *connector;
 236         int i = 0;
 237
 238         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 239                 enabled[i] = drm_connector_enabled(connector, true);
 240                 any_enabled |= enabled[i];
 241                 i++;
 242         }
 243
 244         if (any_enabled)
 245                 return;
 246
 247         i = 0;
 248         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 249                 enabled[i] = drm_connector_enabled(connector, false);
 250                 i++;
 251         }
 252 }
 253
 254 static bool drm_target_preferred(struct drm_device *dev,
 255                                  struct drm_display_mode **modes,
 256                                  bool *enabled, int width, int height)
 257 {
 258         struct drm_connector *connector;
 259         int i = 0;
 260
 261         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 262
 263                 if (enabled[i] == false) {
 264                         i++;
 265                         continue;
 266                 }
 267
 268                 modes[i] = drm_has_preferred_mode(connector, width, height);
 269                 if (!modes[i]) {
 270                         list_for_each_entry(modes[i], &connector->modes, head)
 271                                 break;
 272                 }
 273                 i++;
 274         }
 275         return true;
 276 }
 277
 278 static int drm_pick_crtcs(struct drm_device *dev,
 279                           struct drm_crtc **best_crtcs,
 280                           struct drm_display_mode **modes,
 281                           int n, int width, int height)
 282 {
 283         int c, o;
 284         struct drm_connector *connector;
 285         struct drm_connector_helper_funcs *connector_funcs;
 286         struct drm_encoder *encoder;
 287         struct drm_crtc *best_crtc;
 288         int my_score, best_score, score;
 289         struct drm_crtc **crtcs, *crtc;
 290
 291         if (n == dev->mode_config.num_connector)
 292                 return 0;
 293         c = 0;
 294         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 295                 if (c == n)
 296                         break;
 297                 c++;
 298         }
 299
 300         best_crtcs[n] = NULL;
 301         best_crtc = NULL;
 302         best_score = drm_pick_crtcs(dev, best_crtcs, modes, n+1, width, height);
 303         if (modes[n] == NULL)
 304                 return best_score;
 305
 306         crtcs = kmalloc(dev->mode_config.num_connector *
 307                         sizeof(struct drm_crtc *), GFP_KERNEL);
 308         if (!crtcs)
 309                 return best_score;
 310
 311         my_score = 1;
 312         if (connector->status == connector_status_connected)
 313                 my_score++;
 314         if (drm_has_preferred_mode(connector, width, height))
 315                 my_score++;
 316
 317         connector_funcs = connector->helper_private;
 318         encoder = connector_funcs->best_encoder(connector);
 319         if (!encoder)
 320                 goto out;
 321
 322         connector->encoder = encoder;
 323
 324         /* select a crtc for this connector and then attempt to configure
 325            remaining connectors */
 326         c = 0;
 327         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 328
 329                 if ((connector->encoder->possible_crtcs & (1 << c)) == 0) {
 330                         c++;
 331                         continue;
 332                 }
 333
 334                 for (o = 0; o < n; o++)
 335                         if (best_crtcs[o] == crtc)
 336                                 break;
 337
 338                 if (o < n) {
 339                         /* ignore cloning for now */
 340                         c++;
 341                         continue;
 342                 }
 343
 344                 crtcs[n] = crtc;
 345                 memcpy(crtcs, best_crtcs, n * sizeof(struct drm_crtc *));
 346                 score = my_score + drm_pick_crtcs(dev, crtcs, modes, n + 1,
 347                                                   width, height);
 348                 if (score > best_score) {
 349                         best_crtc = crtc;
 350                         best_score = score;
 351                         memcpy(best_crtcs, crtcs,
 352                                dev->mode_config.num_connector *
 353                                sizeof(struct drm_crtc *));
 354                 }
 355                 c++;
 356         }
 357 out:
 358         kfree(crtcs);
 359         return best_score;
 360 }
 361
 362 static void drm_setup_crtcs(struct drm_device *dev)
 363 {
 364         struct drm_crtc **crtcs;
 365         struct drm_display_mode **modes;
 366         struct drm_encoder *encoder;
 367         struct drm_connector *connector;
 368         bool *enabled;
 369         int width, height;
 370         int i, ret;
 371
 372         width = dev->mode_config.max_width;
 373         height = dev->mode_config.max_height;
 374
 375         /* clean out all the encoder/crtc combos */
 376         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 377                 encoder->crtc = NULL;
 378         }
 379
 380         crtcs = kcalloc(dev->mode_config.num_connector,
 381                         sizeof(struct drm_crtc *), GFP_KERNEL);
 382         modes = kcalloc(dev->mode_config.num_connector,
 383                         sizeof(struct drm_display_mode *), GFP_KERNEL);
 384         enabled = kcalloc(dev->mode_config.num_connector,
 385                           sizeof(bool), GFP_KERNEL);
 386
 387         drm_enable_connectors(dev, enabled);
 388
 389         ret = drm_target_preferred(dev, modes, enabled, width, height);
 390         if (!ret)
 391                 DRM_ERROR("Unable to find initial modes\n");
 392
 393         drm_pick_crtcs(dev, crtcs, modes, 0, width, height);
 394
 395         i = 0;
 396         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 397                 struct drm_display_mode *mode = modes[i];
 398                 struct drm_crtc *crtc = crtcs[i];
 399
 400                 if (connector->encoder == NULL) {
 401                         i++;
 402                         continue;
 403                 }
 404
 405                 if (mode && crtc) {
 406                         crtc->desired_mode = mode;
 407                         connector->encoder->crtc = crtc;
 408                 } else
 409                         connector->encoder->crtc = NULL;
 410                 i++;
 411         }
 412
 413         kfree(crtcs);
 414         kfree(modes);
 415         kfree(enabled);
 416 }
 417 /**
 418  * drm_crtc_set_mode - set a mode
 419  * @crtc: CRTC to program
 420  * @mode: mode to use
 421  * @x: width of mode
 422  * @y: height of mode
 423  *
 424  * LOCKING:
 425  * Caller must hold mode config lock.
 426  *
 427  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 428  * to fixup or reject the mode prior to trying to set it.
 429  *
 430  * RETURNS:
 431  * True if the mode was set successfully, or false otherwise.
 432  */
 433 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 434                               struct drm_display_mode *mode,
 435                               int x, int y)
 436 {
 437         struct drm_device *dev = crtc->dev;
 438         struct drm_display_mode *adjusted_mode, saved_mode;
 439         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 440         struct drm_encoder_helper_funcs *encoder_funcs;
 441         int saved_x, saved_y;
 442         struct drm_encoder *encoder;
 443         bool ret = true;
 444
 445         adjusted_mode = drm_mode_duplicate(dev, mode);
 446
 447         crtc->enabled = drm_helper_crtc_in_use(crtc);
 448
 449         if (!crtc->enabled)
 450                 return true;
 451
 452         saved_mode = crtc->mode;
 453         saved_x = crtc->x;
 454         saved_y = crtc->y;
 455
 456         /* Update crtc values up front so the driver can rely on them for mode
 457          * setting.
 458          */
 459         crtc->mode = *mode;
 460         crtc->x = x;
 461         crtc->y = y;
 462
 463         if (drm_mode_equal(&saved_mode, &crtc->mode)) {
 464                 if (saved_x != crtc->x || saved_y != crtc->y) {
 465                         crtc_funcs->mode_set_base(crtc, crtc->x, crtc->y);
 466                         goto done;
 467                 }
 468         }
 469
 470         /* Pass our mode to the connectors and the CRTC to give them a chance to
 471          * adjust it according to limitations or connector properties, and also
 472          * a chance to reject the mode entirely.
 473          */
 474         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 475
 476                 if (encoder->crtc != crtc)
 477                         continue;
 478                 encoder_funcs = encoder->helper_private;
 479                 if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 480                                                       adjusted_mode))) {
 481                         goto done;
 482                 }
 483         }
 484
 485         if (!(ret = crtc_funcs->mode_fixup(crtc, mode, adjusted_mode))) {
 486                 goto done;
 487         }
 488
 489         /* Prepare the encoders and CRTCs before setting the mode. */
 490         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 491
 492                 if (encoder->crtc != crtc)
 493                         continue;
 494                 encoder_funcs = encoder->helper_private;
 495                 /* Disable the encoders as the first thing we do. */
 496                 encoder_funcs->prepare(encoder);
 497         }
 498
 499         crtc_funcs->prepare(crtc);
 500
 501         /* Set up the DPLL and any encoders state that needs to adjust or depend
 502          * on the DPLL.
 503          */
 504         crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y);
 505
 506         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 507
 508                 if (encoder->crtc != crtc)
 509                         continue;
 510
 511                 DRM_INFO("%s: set mode %s %x\n", drm_get_encoder_name(encoder),
 512                          mode->name, mode->base.id);
 513                 encoder_funcs = encoder->helper_private;
 514                 encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 515         }
 516
 517         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 518         crtc_funcs->commit(crtc);
 519
 520         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 521
 522                 if (encoder->crtc != crtc)
 523                         continue;
 524
 525                 encoder_funcs = encoder->helper_private;
 526                 encoder_funcs->commit(encoder);
 527
 528         }
 529
 530         /* XXX free adjustedmode */
 531         drm_mode_destroy(dev, adjusted_mode);
 532         /* FIXME: add subpixel order */
 533 done:
 534         if (!ret) {
 535                 crtc->mode = saved_mode;
 536                 crtc->x = saved_x;
 537                 crtc->y = saved_y;
 538         }
 539
 540         return ret;
 541 }
 542 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 543
 544
 545 /**
 546  * drm_crtc_helper_set_config - set a new config from userspace
 547  * @crtc: CRTC to setup
 548  * @crtc_info: user provided configuration
 549  * @new_mode: new mode to set
 550  * @connector_set: set of connectors for the new config
 551  * @fb: new framebuffer
 552  *
 553  * LOCKING:
 554  * Caller must hold mode config lock.
 555  *
 556  * Setup a new configuration, provided by the user in @crtc_info, and enable
 557  * it.
 558  *
 559  * RETURNS:
 560  * Zero. (FIXME)
 561  */
 562 int drm_crtc_helper_set_config(struct drm_mode_set *set)
 563 {
 564         struct drm_device *dev;
 565         struct drm_crtc **save_crtcs, *new_crtc;
 566         struct drm_encoder **save_encoders, *new_encoder;
 567         bool save_enabled;
 568         bool changed = false;
 569         bool flip_or_move = false;
 570         struct drm_connector *connector;
 571         int count = 0, ro, fail = 0;
 572         struct drm_crtc_helper_funcs *crtc_funcs;
 573         int ret = 0;
 574
 575         DRM_DEBUG("\n");
 576
 577         if (!set)
 578                 return -EINVAL;
 579
 580         if (!set->crtc)
 581                 return -EINVAL;
 582
 583         if (!set->crtc->helper_private)
 584                 return -EINVAL;
 585
 586         crtc_funcs = set->crtc->helper_private;
 587
 588         DRM_DEBUG("crtc: %p %d fb: %p connectors: %p num_connectors: %d (x, y) (%i, %i)\n",
 589                   set->crtc, set->crtc->base.id, set->fb, set->connectors,
 590                   (int)set->num_connectors, set->x, set->y);
 591
 592         dev = set->crtc->dev;
 593
 594         /* save previous config */
 595         save_enabled = set->crtc->enabled;
 596
 597         /* this is meant to be num_connector not num_crtc */
 598         save_crtcs = kzalloc(dev->mode_config.num_connector *
 599                              sizeof(struct drm_crtc *), GFP_KERNEL);
 600         if (!save_crtcs)
 601                 return -ENOMEM;
 602
 603         save_encoders = kzalloc(dev->mode_config.num_connector *
 604                                 sizeof(struct drm_encoders *), GFP_KERNEL);
 605         if (!save_encoders) {
 606                 kfree(save_crtcs);
 607                 return -ENOMEM;
 608         }
 609
 610         /* We should be able to check here if the fb has the same properties
 611          * and then just flip_or_move it */
 612         if (set->crtc->fb != set->fb) {
 613                 /* if we have no fb then its a change not a flip */
 614                 if (set->crtc->fb == NULL)
 615                         changed = true;
 616                 else
 617                         flip_or_move = true;
 618         }
 619
 620         if (set->x != set->crtc->x || set->y != set->crtc->y)
 621                 flip_or_move = true;
 622
 623         if (set->mode && !drm_mode_equal(set->mode, &set->crtc->mode)) {
 624                 DRM_DEBUG("modes are different\n");
 625                 drm_mode_debug_printmodeline(&set->crtc->mode);
 626                 drm_mode_debug_printmodeline(set->mode);
 627                 changed = true;
 628         }
 629
 630         /* a) traverse passed in connector list and get encoders for them */
 631         count = 0;
 632         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 633                 struct drm_connector_helper_funcs *connector_funcs =
 634                         connector->helper_private;
 635                 save_encoders[count++] = connector->encoder;
 636                 new_encoder = connector->encoder;
 637                 for (ro = 0; ro < set->num_connectors; ro++) {
 638                         if (set->connectors[ro] == connector) {
 639                                 new_encoder = connector_funcs->best_encoder(connector);
 640                                 /* if we can't get an encoder for a connector
 641                                    we are setting now - then fail */
 642                                 if (new_encoder == NULL)
 643                                         /* don't break so fail path works correct */
 644                                         fail = 1;
 645                                 break;
 646                         }
 647                 }
 648
 649                 if (new_encoder != connector->encoder) {
 650                         changed = true;
 651                         connector->encoder = new_encoder;
 652                 }
 653         }
 654
 655         if (fail) {
 656                 ret = -EINVAL;
 657                 goto fail_no_encoder;
 658         }
 659
 660         count = 0;
 661         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 662                 if (!connector->encoder)
 663                         continue;
 664
 665                 save_crtcs[count++] = connector->encoder->crtc;
 666
 667                 if (connector->encoder->crtc == set->crtc)
 668                         new_crtc = NULL;
 669                 else
 670                         new_crtc = connector->encoder->crtc;
 671
 672                 for (ro = 0; ro < set->num_connectors; ro++) {
 673                         if (set->connectors[ro] == connector)
 674                                 new_crtc = set->crtc;
 675                 }
 676                 if (new_crtc != connector->encoder->crtc) {
 677                         changed = true;
 678                         connector->encoder->crtc = new_crtc;
 679                 }
 680         }
 681
 682         /* mode_set_base is not a required function */
 683         if (flip_or_move && !crtc_funcs->mode_set_base)
 684                 changed = true;
 685
 686         if (changed) {
 687                 set->crtc->fb = set->fb;
 688                 set->crtc->enabled = (set->mode != NULL);
 689                 if (set->mode != NULL) {
 690                         DRM_DEBUG("attempting to set mode from userspace\n");
 691                         drm_mode_debug_printmodeline(set->mode);
 692                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 693                                                       set->x, set->y)) {
 694                                 ret = -EINVAL;
 695                                 goto fail_set_mode;
 696                         }
 697                         /* TODO are these needed? */
 698                         set->crtc->desired_x = set->x;
 699                         set->crtc->desired_y = set->y;
 700                         set->crtc->desired_mode = set->mode;
 701                 }
 702                 drm_helper_disable_unused_functions(dev);
 703         } else if (flip_or_move) {
 704                 if (set->crtc->fb != set->fb)
 705                         set->crtc->fb = set->fb;
 706                 crtc_funcs->mode_set_base(set->crtc, set->x, set->y);
 707         }
 708
 709         kfree(save_encoders);
 710         kfree(save_crtcs);
 711         return 0;
 712
 713 fail_set_mode:
 714         set->crtc->enabled = save_enabled;
 715         count = 0;
 716         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 717                 connector->encoder->crtc = save_crtcs[count++];
 718 fail_no_encoder:
 719         kfree(save_crtcs);
 720         count = 0;
 721         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 722                 connector->encoder = save_encoders[count++];
 723         }
 724         kfree(save_encoders);
 725         return ret;
 726 }
 727 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 728
 729 bool drm_helper_plugged_event(struct drm_device *dev)
 730 {
 731         DRM_DEBUG("\n");
 732
 733         drm_helper_probe_connector_modes(dev, dev->mode_config.max_width,
 734                                          dev->mode_config.max_height);
 735
 736         drm_setup_crtcs(dev);
 737
 738         /* alert the driver fb layer */
 739         dev->mode_config.funcs->fb_changed(dev);
 740
 741         /* FIXME: send hotplug event */
 742         return true;
 743 }
 744 /**
 745  * drm_initial_config - setup a sane initial connector configuration
 746  * @dev: DRM device
 747  * @can_grow: this configuration is growable
 748  *
 749  * LOCKING:
 750  * Called at init time, must take mode config lock.
 751  *
 752  * Scan the CRTCs and connectors and try to put together an initial setup.
 753  * At the moment, this is a cloned configuration across all heads with
 754  * a new framebuffer object as the backing store.
 755  *
 756  * RETURNS:
 757  * Zero if everything went ok, nonzero otherwise.
 758  */
 759 bool drm_helper_initial_config(struct drm_device *dev, bool can_grow)
 760 {
 761         int ret = false;
 762
 763         drm_helper_plugged_event(dev);
 764         return ret;
 765 }
 766 EXPORT_SYMBOL(drm_helper_initial_config);
 767
 768 /**
 769  * drm_hotplug_stage_two
 770  * @dev DRM device
 771  * @connector hotpluged connector
 772  *
 773  * LOCKING.
 774  * Caller must hold mode config lock, function might grab struct lock.
 775  *
 776  * Stage two of a hotplug.
 777  *
 778  * RETURNS:
 779  * Zero on success, errno on failure.
 780  */
 781 int drm_helper_hotplug_stage_two(struct drm_device *dev)
 782 {
 783         dev->mode_config.hotplug_counter++;
 784
 785         drm_helper_plugged_event(dev);
 786
 787         return 0;
 788 }
 789 EXPORT_SYMBOL(drm_helper_hotplug_stage_two);
 790
 791 int drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
 792                                    struct drm_mode_fb_cmd *mode_cmd)
 793 {
 794         fb->width = mode_cmd->width;
 795         fb->height = mode_cmd->height;
 796         fb->pitch = mode_cmd->pitch;
 797         fb->bits_per_pixel = mode_cmd->bpp;
 798         fb->depth = mode_cmd->depth;
 799
 800         return 0;
 801 }
 802 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
 803
 804 int drm_helper_resume_force_mode(struct drm_device *dev)
 805 {
 806         struct drm_crtc *crtc;
 807         int ret;
 808
 809         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 810
 811                 if (!crtc->enabled)
 812                         continue;
 813
 814                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode, crtc->x,
 815                                                crtc->y);
 816
 817                 if (ret == false)
 818                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 819         }
 820         return 0;
 821 }
 822 EXPORT_SYMBOL(drm_helper_resume_force_mode);