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 800x600@60Hz
  38  */
  39 static struct drm_display_mode std_modes[] = {
  40         { DRM_MODE("800x600", DRM_MODE_TYPE_DEFAULT, 40000, 800, 840,
  41                    968, 1056, 0, 600, 601, 605, 628, 0,
  42                    DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC) },
  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  * RETURNS:
  65  * Number of modes found on @connector.
  66  */
  67 int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
  68                                             uint32_t maxX, uint32_t maxY)
  69 {
  70         struct drm_device *dev = connector->dev;
  71         struct drm_display_mode *mode, *t;
  72         struct drm_connector_helper_funcs *connector_funcs =
  73                 connector->helper_private;
  74         int count = 0;
  75
  76         DRM_DEBUG("%s\n", drm_get_connector_name(connector));
  77         /* set all modes to the unverified state */
  78         list_for_each_entry_safe(mode, t, &connector->modes, head)
  79                 mode->status = MODE_UNVERIFIED;
  80
  81         connector->status = connector->funcs->detect(connector);
  82
  83         if (connector->status == connector_status_disconnected) {
  84                 DRM_DEBUG("%s is disconnected\n",
  85                           drm_get_connector_name(connector));
  86                 /* TODO set EDID to NULL */
  87                 return 0;
  88         }
  89
  90         count = (*connector_funcs->get_modes)(connector);
  91         if (!count)
  92                 return 0;
  93
  94         drm_mode_connector_list_update(connector);
  95
  96         if (maxX && maxY)
  97                 drm_mode_validate_size(dev, &connector->modes, maxX,
  98                                        maxY, 0);
  99         list_for_each_entry_safe(mode, t, &connector->modes, head) {
 100                 if (mode->status == MODE_OK)
 101                         mode->status = connector_funcs->mode_valid(connector,
 102                                                                    mode);
 103         }
 104
 105
 106         drm_mode_prune_invalid(dev, &connector->modes, true);
 107
 108         if (list_empty(&connector->modes))
 109                 return 0;
 110
 111         drm_mode_sort(&connector->modes);
 112
 113         DRM_DEBUG("Probed modes for %s\n", drm_get_connector_name(connector));
 114         list_for_each_entry_safe(mode, t, &connector->modes, head) {
 115                 mode->vrefresh = drm_mode_vrefresh(mode);
 116
 117                 drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
 118                 drm_mode_debug_printmodeline(mode);
 119         }
 120
 121         return count;
 122 }
 123 EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
 124
 125 int drm_helper_probe_connector_modes(struct drm_device *dev, uint32_t maxX,
 126                                       uint32_t maxY)
 127 {
 128         struct drm_connector *connector;
 129         int count = 0;
 130
 131         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 132                 count += drm_helper_probe_single_connector_modes(connector,
 133                                                                  maxX, maxY);
 134         }
 135
 136         return count;
 137 }
 138 EXPORT_SYMBOL(drm_helper_probe_connector_modes);
 139
 140 static void drm_helper_add_std_modes(struct drm_device *dev,
 141                                      struct drm_connector *connector)
 142 {
 143         struct drm_display_mode *mode, *t;
 144         int i;
 145
 146         for (i = 0; i < ARRAY_SIZE(std_modes); i++) {
 147                 struct drm_display_mode *stdmode;
 148
 149                 /*
 150                  * When no valid EDID modes are available we end up
 151                  * here and bailed in the past, now we add some standard
 152                  * modes and move on.
 153                  */
 154                 stdmode = drm_mode_duplicate(dev, &std_modes[i]);
 155                 drm_mode_probed_add(connector, stdmode);
 156                 drm_mode_list_concat(&connector->probed_modes,
 157                                      &connector->modes);
 158
 159                 DRM_DEBUG("Adding mode %s to %s\n", stdmode->name,
 160                           drm_get_connector_name(connector));
 161         }
 162         drm_mode_sort(&connector->modes);
 163
 164         DRM_DEBUG("Added std modes on %s\n", drm_get_connector_name(connector));
 165         list_for_each_entry_safe(mode, t, &connector->modes, head) {
 166                 mode->vrefresh = drm_mode_vrefresh(mode);
 167
 168                 drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
 169                 drm_mode_debug_printmodeline(mode);
 170         }
 171 }
 172
 173 /**
 174  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 175  * @crtc: CRTC to check
 176  *
 177  * LOCKING:
 178  * Caller must hold mode config lock.
 179  *
 180  * Walk @crtc's DRM device's mode_config and see if it's in use.
 181  *
 182  * RETURNS:
 183  * True if @crtc is part of the mode_config, false otherwise.
 184  */
 185 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 186 {
 187         struct drm_encoder *encoder;
 188         struct drm_device *dev = crtc->dev;
 189         /* FIXME: Locking around list access? */
 190         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
 191                 if (encoder->crtc == crtc)
 192                         return true;
 193         return false;
 194 }
 195 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 196
 197 /**
 198  * drm_disable_unused_functions - disable unused objects
 199  * @dev: DRM device
 200  *
 201  * LOCKING:
 202  * Caller must hold mode config lock.
 203  *
 204  * If an connector or CRTC isn't part of @dev's mode_config, it can be disabled
 205  * by calling its dpms function, which should power it off.
 206  */
 207 void drm_helper_disable_unused_functions(struct drm_device *dev)
 208 {
 209         struct drm_encoder *encoder;
 210         struct drm_encoder_helper_funcs *encoder_funcs;
 211         struct drm_crtc *crtc;
 212
 213         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 214                 encoder_funcs = encoder->helper_private;
 215                 if (!encoder->crtc)
 216                         (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 217         }
 218
 219         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 220                 struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 221                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 222                 if (!crtc->enabled) {
 223                         crtc_funcs->dpms(crtc, DRM_MODE_DPMS_OFF);
 224                         crtc->fb = NULL;
 225                 }
 226         }
 227 }
 228 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 229
 230 static struct drm_display_mode *drm_has_preferred_mode(struct drm_connector *connector, int width, int height)
 231 {
 232         struct drm_display_mode *mode;
 233
 234         list_for_each_entry(mode, &connector->modes, head) {
 235                 if (drm_mode_width(mode) > width ||
 236                     drm_mode_height(mode) > height)
 237                         continue;
 238                 if (mode->type & DRM_MODE_TYPE_PREFERRED)
 239                         return mode;
 240         }
 241         return NULL;
 242 }
 243
 244 static bool drm_connector_enabled(struct drm_connector *connector, bool strict)
 245 {
 246         bool enable;
 247
 248         if (strict) {
 249                 enable = connector->status == connector_status_connected;
 250         } else {
 251                 enable = connector->status != connector_status_disconnected;
 252         }
 253         return enable;
 254 }
 255
 256 static void drm_enable_connectors(struct drm_device *dev, bool *enabled)
 257 {
 258         bool any_enabled = false;
 259         struct drm_connector *connector;
 260         int i = 0;
 261
 262         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 263                 enabled[i] = drm_connector_enabled(connector, true);
 264                 DRM_DEBUG("connector %d enabled? %s\n", connector->base.id,
 265                           enabled[i] ? "yes" : "no");
 266                 any_enabled |= enabled[i];
 267                 i++;
 268         }
 269
 270         if (any_enabled)
 271                 return;
 272
 273         i = 0;
 274         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 275                 enabled[i] = drm_connector_enabled(connector, false);
 276                 i++;
 277         }
 278 }
 279
 280 static bool drm_target_preferred(struct drm_device *dev,
 281                                  struct drm_display_mode **modes,
 282                                  bool *enabled, int width, int height)
 283 {
 284         struct drm_connector *connector;
 285         int i = 0;
 286
 287         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 288
 289                 if (enabled[i] == false) {
 290                         i++;
 291                         continue;
 292                 }
 293
 294                 DRM_DEBUG("looking for preferred mode on connector %d\n",
 295                           connector->base.id);
 296
 297                 modes[i] = drm_has_preferred_mode(connector, width, height);
 298                 /* No preferred modes, pick one off the list */
 299                 if (!modes[i] && !list_empty(&connector->modes)) {
 300                         list_for_each_entry(modes[i], &connector->modes, head)
 301                                 break;
 302                 }
 303                 DRM_DEBUG("found mode %s\n", modes[i] ? modes[i]->name :
 304                           "none");
 305                 i++;
 306         }
 307         return true;
 308 }
 309
 310 static int drm_pick_crtcs(struct drm_device *dev,
 311                           struct drm_crtc **best_crtcs,
 312                           struct drm_display_mode **modes,
 313                           int n, int width, int height)
 314 {
 315         int c, o;
 316         struct drm_connector *connector;
 317         struct drm_connector_helper_funcs *connector_funcs;
 318         struct drm_encoder *encoder;
 319         struct drm_crtc *best_crtc;
 320         int my_score, best_score, score;
 321         struct drm_crtc **crtcs, *crtc;
 322
 323         if (n == dev->mode_config.num_connector)
 324                 return 0;
 325         c = 0;
 326         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 327                 if (c == n)
 328                         break;
 329                 c++;
 330         }
 331
 332         best_crtcs[n] = NULL;
 333         best_crtc = NULL;
 334         best_score = drm_pick_crtcs(dev, best_crtcs, modes, n+1, width, height);
 335         if (modes[n] == NULL)
 336                 return best_score;
 337
 338         crtcs = kmalloc(dev->mode_config.num_connector *
 339                         sizeof(struct drm_crtc *), GFP_KERNEL);
 340         if (!crtcs)
 341                 return best_score;
 342
 343         my_score = 1;
 344         if (connector->status == connector_status_connected)
 345                 my_score++;
 346         if (drm_has_preferred_mode(connector, width, height))
 347                 my_score++;
 348
 349         connector_funcs = connector->helper_private;
 350         encoder = connector_funcs->best_encoder(connector);
 351         if (!encoder)
 352                 goto out;
 353
 354         connector->encoder = encoder;
 355
 356         /* select a crtc for this connector and then attempt to configure
 357            remaining connectors */
 358         c = 0;
 359         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 360
 361                 if ((connector->encoder->possible_crtcs & (1 << c)) == 0) {
 362                         c++;
 363                         continue;
 364                 }
 365
 366                 for (o = 0; o < n; o++)
 367                         if (best_crtcs[o] == crtc)
 368                                 break;
 369
 370                 if (o < n) {
 371                         /* ignore cloning for now */
 372                         c++;
 373                         continue;
 374                 }
 375
 376                 crtcs[n] = crtc;
 377                 memcpy(crtcs, best_crtcs, n * sizeof(struct drm_crtc *));
 378                 score = my_score + drm_pick_crtcs(dev, crtcs, modes, n + 1,
 379                                                   width, height);
 380                 if (score > best_score) {
 381                         best_crtc = crtc;
 382                         best_score = score;
 383                         memcpy(best_crtcs, crtcs,
 384                                dev->mode_config.num_connector *
 385                                sizeof(struct drm_crtc *));
 386                 }
 387                 c++;
 388         }
 389 out:
 390         kfree(crtcs);
 391         return best_score;
 392 }
 393
 394 static void drm_setup_crtcs(struct drm_device *dev)
 395 {
 396         struct drm_crtc **crtcs;
 397         struct drm_display_mode **modes;
 398         struct drm_encoder *encoder;
 399         struct drm_connector *connector;
 400         bool *enabled;
 401         int width, height;
 402         int i, ret;
 403
 404         DRM_DEBUG("\n");
 405
 406         width = dev->mode_config.max_width;
 407         height = dev->mode_config.max_height;
 408
 409         /* clean out all the encoder/crtc combos */
 410         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 411                 encoder->crtc = NULL;
 412         }
 413
 414         crtcs = kcalloc(dev->mode_config.num_connector,
 415                         sizeof(struct drm_crtc *), GFP_KERNEL);
 416         modes = kcalloc(dev->mode_config.num_connector,
 417                         sizeof(struct drm_display_mode *), GFP_KERNEL);
 418         enabled = kcalloc(dev->mode_config.num_connector,
 419                           sizeof(bool), GFP_KERNEL);
 420
 421         drm_enable_connectors(dev, enabled);
 422
 423         ret = drm_target_preferred(dev, modes, enabled, width, height);
 424         if (!ret)
 425                 DRM_ERROR("Unable to find initial modes\n");
 426
 427         DRM_DEBUG("picking CRTCs for %dx%d config\n", width, height);
 428
 429         drm_pick_crtcs(dev, crtcs, modes, 0, width, height);
 430
 431         i = 0;
 432         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 433                 struct drm_display_mode *mode = modes[i];
 434                 struct drm_crtc *crtc = crtcs[i];
 435
 436                 if (connector->encoder == NULL) {
 437                         i++;
 438                         continue;
 439                 }
 440
 441                 if (mode && crtc) {
 442                         DRM_DEBUG("desired mode %s set on crtc %d\n",
 443                                   mode->name, crtc->base.id);
 444                         crtc->desired_mode = mode;
 445                         connector->encoder->crtc = crtc;
 446                 } else
 447                         connector->encoder->crtc = NULL;
 448                 i++;
 449         }
 450
 451         kfree(crtcs);
 452         kfree(modes);
 453         kfree(enabled);
 454 }
 455 /**
 456  * drm_crtc_set_mode - set a mode
 457  * @crtc: CRTC to program
 458  * @mode: mode to use
 459  * @x: width of mode
 460  * @y: height of mode
 461  *
 462  * LOCKING:
 463  * Caller must hold mode config lock.
 464  *
 465  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 466  * to fixup or reject the mode prior to trying to set it.
 467  *
 468  * RETURNS:
 469  * True if the mode was set successfully, or false otherwise.
 470  */
 471 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 472                               struct drm_display_mode *mode,
 473                               int x, int y,
 474                               struct drm_framebuffer *old_fb)
 475 {
 476         struct drm_device *dev = crtc->dev;
 477         struct drm_display_mode *adjusted_mode, saved_mode;
 478         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 479         struct drm_encoder_helper_funcs *encoder_funcs;
 480         int saved_x, saved_y;
 481         struct drm_encoder *encoder;
 482         bool ret = true;
 483
 484         adjusted_mode = drm_mode_duplicate(dev, mode);
 485
 486         crtc->enabled = drm_helper_crtc_in_use(crtc);
 487
 488         if (!crtc->enabled)
 489                 return true;
 490
 491         saved_mode = crtc->mode;
 492         saved_x = crtc->x;
 493         saved_y = crtc->y;
 494
 495         /* Update crtc values up front so the driver can rely on them for mode
 496          * setting.
 497          */
 498         crtc->mode = *mode;
 499         crtc->x = x;
 500         crtc->y = y;
 501
 502         if (drm_mode_equal(&saved_mode, &crtc->mode)) {
 503                 if (saved_x != crtc->x || saved_y != crtc->y) {
 504                         crtc_funcs->mode_set_base(crtc, crtc->x, crtc->y,
 505                                                   old_fb);
 506                         goto done;
 507                 }
 508         }
 509
 510         /* Pass our mode to the connectors and the CRTC to give them a chance to
 511          * adjust it according to limitations or connector properties, and also
 512          * a chance to reject the mode entirely.
 513          */
 514         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 515
 516                 if (encoder->crtc != crtc)
 517                         continue;
 518                 encoder_funcs = encoder->helper_private;
 519                 if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 520                                                       adjusted_mode))) {
 521                         goto done;
 522                 }
 523         }
 524
 525         if (!(ret = crtc_funcs->mode_fixup(crtc, mode, adjusted_mode))) {
 526                 goto done;
 527         }
 528
 529         /* Prepare the encoders and CRTCs before setting the mode. */
 530         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 531
 532                 if (encoder->crtc != crtc)
 533                         continue;
 534                 encoder_funcs = encoder->helper_private;
 535                 /* Disable the encoders as the first thing we do. */
 536                 encoder_funcs->prepare(encoder);
 537         }
 538
 539         crtc_funcs->prepare(crtc);
 540
 541         /* Set up the DPLL and any encoders state that needs to adjust or depend
 542          * on the DPLL.
 543          */
 544         crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 545
 546         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 547
 548                 if (encoder->crtc != crtc)
 549                         continue;
 550
 551                 DRM_INFO("%s: set mode %s %x\n", drm_get_encoder_name(encoder),
 552                          mode->name, mode->base.id);
 553                 encoder_funcs = encoder->helper_private;
 554                 encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 555         }
 556
 557         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 558         crtc_funcs->commit(crtc);
 559
 560         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 561
 562                 if (encoder->crtc != crtc)
 563                         continue;
 564
 565                 encoder_funcs = encoder->helper_private;
 566                 encoder_funcs->commit(encoder);
 567
 568         }
 569
 570         /* XXX free adjustedmode */
 571         drm_mode_destroy(dev, adjusted_mode);
 572         /* FIXME: add subpixel order */
 573 done:
 574         if (!ret) {
 575                 crtc->mode = saved_mode;
 576                 crtc->x = saved_x;
 577                 crtc->y = saved_y;
 578         }
 579
 580         return ret;
 581 }
 582 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 583
 584
 585 /**
 586  * drm_crtc_helper_set_config - set a new config from userspace
 587  * @crtc: CRTC to setup
 588  * @crtc_info: user provided configuration
 589  * @new_mode: new mode to set
 590  * @connector_set: set of connectors for the new config
 591  * @fb: new framebuffer
 592  *
 593  * LOCKING:
 594  * Caller must hold mode config lock.
 595  *
 596  * Setup a new configuration, provided by the user in @crtc_info, and enable
 597  * it.
 598  *
 599  * RETURNS:
 600  * Zero. (FIXME)
 601  */
 602 int drm_crtc_helper_set_config(struct drm_mode_set *set)
 603 {
 604         struct drm_device *dev;
 605         struct drm_crtc **save_crtcs, *new_crtc;
 606         struct drm_encoder **save_encoders, *new_encoder;
 607         struct drm_framebuffer *old_fb;
 608         bool save_enabled;
 609         bool changed = false;
 610         bool flip_or_move = false;
 611         struct drm_connector *connector;
 612         int count = 0, ro, fail = 0;
 613         struct drm_crtc_helper_funcs *crtc_funcs;
 614         int ret = 0;
 615
 616         DRM_DEBUG("\n");
 617
 618         if (!set)
 619                 return -EINVAL;
 620
 621         if (!set->crtc)
 622                 return -EINVAL;
 623
 624         if (!set->crtc->helper_private)
 625                 return -EINVAL;
 626
 627         crtc_funcs = set->crtc->helper_private;
 628
 629         DRM_DEBUG("crtc: %p %d fb: %p connectors: %p num_connectors: %d (x, y) (%i, %i)\n",
 630                   set->crtc, set->crtc->base.id, set->fb, set->connectors,
 631                   (int)set->num_connectors, set->x, set->y);
 632
 633         dev = set->crtc->dev;
 634
 635         /* save previous config */
 636         save_enabled = set->crtc->enabled;
 637
 638         /* this is meant to be num_connector not num_crtc */
 639         save_crtcs = kzalloc(dev->mode_config.num_connector *
 640                              sizeof(struct drm_crtc *), GFP_KERNEL);
 641         if (!save_crtcs)
 642                 return -ENOMEM;
 643
 644         save_encoders = kzalloc(dev->mode_config.num_connector *
 645                                 sizeof(struct drm_encoders *), GFP_KERNEL);
 646         if (!save_encoders) {
 647                 kfree(save_crtcs);
 648                 return -ENOMEM;
 649         }
 650
 651         /* We should be able to check here if the fb has the same properties
 652          * and then just flip_or_move it */
 653         if (set->crtc->fb != set->fb) {
 654                 /* if we have no fb then its a change not a flip */
 655                 if (set->crtc->fb == NULL)
 656                         changed = true;
 657                 else
 658                         flip_or_move = true;
 659         }
 660
 661         if (set->x != set->crtc->x || set->y != set->crtc->y)
 662                 flip_or_move = true;
 663
 664         if (set->mode && !drm_mode_equal(set->mode, &set->crtc->mode)) {
 665                 DRM_DEBUG("modes are different\n");
 666                 drm_mode_debug_printmodeline(&set->crtc->mode);
 667                 drm_mode_debug_printmodeline(set->mode);
 668                 changed = true;
 669         }
 670
 671         /* a) traverse passed in connector list and get encoders for them */
 672         count = 0;
 673         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 674                 struct drm_connector_helper_funcs *connector_funcs =
 675                         connector->helper_private;
 676                 save_encoders[count++] = connector->encoder;
 677                 new_encoder = connector->encoder;
 678                 for (ro = 0; ro < set->num_connectors; ro++) {
 679                         if (set->connectors[ro] == connector) {
 680                                 new_encoder = connector_funcs->best_encoder(connector);
 681                                 /* if we can't get an encoder for a connector
 682                                    we are setting now - then fail */
 683                                 if (new_encoder == NULL)
 684                                         /* don't break so fail path works correct */
 685                                         fail = 1;
 686                                 break;
 687                         }
 688                 }
 689
 690                 if (new_encoder != connector->encoder) {
 691                         changed = true;
 692                         connector->encoder = new_encoder;
 693                 }
 694         }
 695
 696         if (fail) {
 697                 ret = -EINVAL;
 698                 goto fail_no_encoder;
 699         }
 700
 701         count = 0;
 702         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 703                 if (!connector->encoder)
 704                         continue;
 705
 706                 save_crtcs[count++] = connector->encoder->crtc;
 707
 708                 if (connector->encoder->crtc == set->crtc)
 709                         new_crtc = NULL;
 710                 else
 711                         new_crtc = connector->encoder->crtc;
 712
 713                 for (ro = 0; ro < set->num_connectors; ro++) {
 714                         if (set->connectors[ro] == connector)
 715                                 new_crtc = set->crtc;
 716                 }
 717                 if (new_crtc != connector->encoder->crtc) {
 718                         changed = true;
 719                         connector->encoder->crtc = new_crtc;
 720                 }
 721         }
 722
 723         /* mode_set_base is not a required function */
 724         if (flip_or_move && !crtc_funcs->mode_set_base)
 725                 changed = true;
 726
 727         if (changed) {
 728                 old_fb = set->crtc->fb;
 729                 set->crtc->fb = set->fb;
 730                 set->crtc->enabled = (set->mode != NULL);
 731                 if (set->mode != NULL) {
 732                         DRM_DEBUG("attempting to set mode from userspace\n");
 733                         drm_mode_debug_printmodeline(set->mode);
 734                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 735                                                       set->x, set->y,
 736                                                       old_fb)) {
 737                                 ret = -EINVAL;
 738                                 goto fail_set_mode;
 739                         }
 740                         /* TODO are these needed? */
 741                         set->crtc->desired_x = set->x;
 742                         set->crtc->desired_y = set->y;
 743                         set->crtc->desired_mode = set->mode;
 744                 }
 745                 drm_helper_disable_unused_functions(dev);
 746         } else if (flip_or_move) {
 747                 old_fb = set->crtc->fb;
 748                 if (set->crtc->fb != set->fb)
 749                         set->crtc->fb = set->fb;
 750                 crtc_funcs->mode_set_base(set->crtc, set->x, set->y, old_fb);
 751         }
 752
 753         kfree(save_encoders);
 754         kfree(save_crtcs);
 755         return 0;
 756
 757 fail_set_mode:
 758         set->crtc->enabled = save_enabled;
 759         count = 0;
 760         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 761                 connector->encoder->crtc = save_crtcs[count++];
 762 fail_no_encoder:
 763         kfree(save_crtcs);
 764         count = 0;
 765         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 766                 connector->encoder = save_encoders[count++];
 767         }
 768         kfree(save_encoders);
 769         return ret;
 770 }
 771 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 772
 773 bool drm_helper_plugged_event(struct drm_device *dev)
 774 {
 775         DRM_DEBUG("\n");
 776
 777         drm_helper_probe_connector_modes(dev, dev->mode_config.max_width,
 778                                          dev->mode_config.max_height);
 779
 780         drm_setup_crtcs(dev);
 781
 782         /* alert the driver fb layer */
 783         dev->mode_config.funcs->fb_changed(dev);
 784
 785         /* FIXME: send hotplug event */
 786         return true;
 787 }
 788 /**
 789  * drm_initial_config - setup a sane initial connector configuration
 790  * @dev: DRM device
 791  * @can_grow: this configuration is growable
 792  *
 793  * LOCKING:
 794  * Called at init time, must take mode config lock.
 795  *
 796  * Scan the CRTCs and connectors and try to put together an initial setup.
 797  * At the moment, this is a cloned configuration across all heads with
 798  * a new framebuffer object as the backing store.
 799  *
 800  * RETURNS:
 801  * Zero if everything went ok, nonzero otherwise.
 802  */
 803 bool drm_helper_initial_config(struct drm_device *dev, bool can_grow)
 804 {
 805         struct drm_connector *connector;
 806         int count = 0;
 807
 808         count = drm_helper_probe_connector_modes(dev,
 809                                                  dev->mode_config.max_width,
 810                                                  dev->mode_config.max_height);
 811
 812         /*
 813          * None of the available connectors had any modes, so add some
 814          * and try to light them up anyway
 815          */
 816         if (!count) {
 817                 DRM_ERROR("connectors have no modes, using standard modes\n");
 818                 list_for_each_entry(connector,
 819                                     &dev->mode_config.connector_list,
 820                                     head)
 821                         drm_helper_add_std_modes(dev, connector);
 822         }
 823
 824         drm_setup_crtcs(dev);
 825
 826         /* alert the driver fb layer */
 827         dev->mode_config.funcs->fb_changed(dev);
 828
 829         return 0;
 830 }
 831 EXPORT_SYMBOL(drm_helper_initial_config);
 832
 833 /**
 834  * drm_hotplug_stage_two
 835  * @dev DRM device
 836  * @connector hotpluged connector
 837  *
 838  * LOCKING.
 839  * Caller must hold mode config lock, function might grab struct lock.
 840  *
 841  * Stage two of a hotplug.
 842  *
 843  * RETURNS:
 844  * Zero on success, errno on failure.
 845  */
 846 int drm_helper_hotplug_stage_two(struct drm_device *dev)
 847 {
 848         drm_helper_plugged_event(dev);
 849
 850         return 0;
 851 }
 852 EXPORT_SYMBOL(drm_helper_hotplug_stage_two);
 853
 854 int drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
 855                                    struct drm_mode_fb_cmd *mode_cmd)
 856 {
 857         fb->width = mode_cmd->width;
 858         fb->height = mode_cmd->height;
 859         fb->pitch = mode_cmd->pitch;
 860         fb->bits_per_pixel = mode_cmd->bpp;
 861         fb->depth = mode_cmd->depth;
 862
 863         return 0;
 864 }
 865 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
 866
 867 int drm_helper_resume_force_mode(struct drm_device *dev)
 868 {
 869         struct drm_crtc *crtc;
 870         int ret;
 871
 872         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 873
 874                 if (!crtc->enabled)
 875                         continue;
 876
 877                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 878                                                crtc->x, crtc->y, crtc->fb);
 879
 880                 if (ret == false)
 881                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 882         }
 883         return 0;
 884 }
 885 EXPORT_SYMBOL(drm_helper_resume_force_mode);