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 <linux/kernel.h>
  33 #include <linux/export.h>
  34 #include <linux/moduleparam.h>
  35
  36 #include <drm/drmP.h>
  37 #include <drm/drm_crtc.h>
  38 #include <drm/drm_fourcc.h>
  39 #include <drm/drm_crtc_helper.h>
  40 #include <drm/drm_fb_helper.h>
  41 #include <drm/drm_edid.h>
  42
  43 MODULE_AUTHOR("David Airlie, Jesse Barnes");
  44 MODULE_DESCRIPTION("DRM KMS helper");
  45 MODULE_LICENSE("GPL and additional rights");
  46
  47 /**
  48  * drm_helper_move_panel_connectors_to_head() - move panels to the front in the
  49  *                                              connector list
  50  * @dev: drm device to operate on
  51  *
  52  * Some userspace presumes that the first connected connector is the main
  53  * display, where it's supposed to display e.g. the login screen. For
  54  * laptops, this should be the main panel. Use this function to sort all
  55  * (eDP/LVDS) panels to the front of the connector list, instead of
  56  * painstakingly trying to initialize them in the right order.
  57  */
  58 void drm_helper_move_panel_connectors_to_head(struct drm_device *dev)
  59 {
  60         struct drm_connector *connector, *tmp;
  61         struct list_head panel_list;
  62
  63         INIT_LIST_HEAD(&panel_list);
  64
  65         list_for_each_entry_safe(connector, tmp,
  66                                  &dev->mode_config.connector_list, head) {
  67                 if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
  68                     connector->connector_type == DRM_MODE_CONNECTOR_eDP)
  69                         list_move_tail(&connector->head, &panel_list);
  70         }
  71
  72         list_splice(&panel_list, &dev->mode_config.connector_list);
  73 }
  74 EXPORT_SYMBOL(drm_helper_move_panel_connectors_to_head);
  75
  76 /**
  77  * drm_helper_encoder_in_use - check if a given encoder is in use
  78  * @encoder: encoder to check
  79  *
  80  * Checks whether @encoder is with the current mode setting output configuration
  81  * in use by any connector. This doesn't mean that it is actually enabled since
  82  * the DPMS state is tracked separately.
  83  *
  84  * Returns:
  85  * True if @encoder is used, false otherwise.
  86  */
  87 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
  88 {
  89         struct drm_connector *connector;
  90         struct drm_device *dev = encoder->dev;
  91
  92         /*
  93          * We can expect this mutex to be locked if we are not panicking.
  94          * Locking is currently fubar in the panic handler.
  95          */
  96         if (!oops_in_progress) {
  97                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
  98                 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
  99         }
 100
 101         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 102                 if (connector->encoder == encoder)
 103                         return true;
 104         return false;
 105 }
 106 EXPORT_SYMBOL(drm_helper_encoder_in_use);
 107
 108 /**
 109  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 110  * @crtc: CRTC to check
 111  *
 112  * Checks whether @crtc is with the current mode setting output configuration
 113  * in use by any connector. This doesn't mean that it is actually enabled since
 114  * the DPMS state is tracked separately.
 115  *
 116  * Returns:
 117  * True if @crtc is used, false otherwise.
 118  */
 119 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 120 {
 121         struct drm_encoder *encoder;
 122         struct drm_device *dev = crtc->dev;
 123
 124         /*
 125          * We can expect this mutex to be locked if we are not panicking.
 126          * Locking is currently fubar in the panic handler.
 127          */
 128         if (!oops_in_progress)
 129                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 130
 131         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
 132                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 133                         return true;
 134         return false;
 135 }
 136 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 137
 138 static void
 139 drm_encoder_disable(struct drm_encoder *encoder)
 140 {
 141         struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 142
 143         if (encoder->bridge)
 144                 encoder->bridge->funcs->disable(encoder->bridge);
 145
 146         if (encoder_funcs->disable)
 147                 (*encoder_funcs->disable)(encoder);
 148         else
 149                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 150
 151         if (encoder->bridge)
 152                 encoder->bridge->funcs->post_disable(encoder->bridge);
 153 }
 154
 155 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 156 {
 157         struct drm_encoder *encoder;
 158         struct drm_crtc *crtc;
 159
 160         drm_warn_on_modeset_not_all_locked(dev);
 161
 162         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 163                 if (!drm_helper_encoder_in_use(encoder)) {
 164                         drm_encoder_disable(encoder);
 165                         /* disconnect encoder from any connector */
 166                         encoder->crtc = NULL;
 167                 }
 168         }
 169
 170         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 171                 struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 172                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 173                 if (!crtc->enabled) {
 174                         if (crtc_funcs->disable)
 175                                 (*crtc_funcs->disable)(crtc);
 176                         else
 177                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 178                         crtc->primary->fb = NULL;
 179                 }
 180         }
 181 }
 182
 183 /**
 184  * drm_helper_disable_unused_functions - disable unused objects
 185  * @dev: DRM device
 186  *
 187  * This function walks through the entire mode setting configuration of @dev. It
 188  * will remove any crtc links of unused encoders and encoder links of
 189  * disconnected connectors. Then it will disable all unused encoders and crtcs
 190  * either by calling their disable callback if available or by calling their
 191  * dpms callback with DRM_MODE_DPMS_OFF.
 192  */
 193 void drm_helper_disable_unused_functions(struct drm_device *dev)
 194 {
 195         drm_modeset_lock_all(dev);
 196         __drm_helper_disable_unused_functions(dev);
 197         drm_modeset_unlock_all(dev);
 198 }
 199 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 200
 201 /*
 202  * Check the CRTC we're going to map each output to vs. its current
 203  * CRTC.  If they don't match, we have to disable the output and the CRTC
 204  * since the driver will have to re-route things.
 205  */
 206 static void
 207 drm_crtc_prepare_encoders(struct drm_device *dev)
 208 {
 209         struct drm_encoder_helper_funcs *encoder_funcs;
 210         struct drm_encoder *encoder;
 211
 212         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 213                 encoder_funcs = encoder->helper_private;
 214                 /* Disable unused encoders */
 215                 if (encoder->crtc == NULL)
 216                         drm_encoder_disable(encoder);
 217                 /* Disable encoders whose CRTC is about to change */
 218                 if (encoder_funcs->get_crtc &&
 219                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
 220                         drm_encoder_disable(encoder);
 221         }
 222 }
 223
 224 /**
 225  * drm_crtc_helper_set_mode - internal helper to set a mode
 226  * @crtc: CRTC to program
 227  * @mode: mode to use
 228  * @x: horizontal offset into the surface
 229  * @y: vertical offset into the surface
 230  * @old_fb: old framebuffer, for cleanup
 231  *
 232  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 233  * to fixup or reject the mode prior to trying to set it. This is an internal
 234  * helper that drivers could e.g. use to update properties that require the
 235  * entire output pipe to be disabled and re-enabled in a new configuration. For
 236  * example for changing whether audio is enabled on a hdmi link or for changing
 237  * panel fitter or dither attributes. It is also called by the
 238  * drm_crtc_helper_set_config() helper function to drive the mode setting
 239  * sequence.
 240  *
 241  * Returns:
 242  * True if the mode was set successfully, false otherwise.
 243  */
 244 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 245                               struct drm_display_mode *mode,
 246                               int x, int y,
 247                               struct drm_framebuffer *old_fb)
 248 {
 249         struct drm_device *dev = crtc->dev;
 250         struct drm_display_mode *adjusted_mode, saved_mode;
 251         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 252         struct drm_encoder_helper_funcs *encoder_funcs;
 253         int saved_x, saved_y;
 254         bool saved_enabled;
 255         struct drm_encoder *encoder;
 256         bool ret = true;
 257
 258         drm_warn_on_modeset_not_all_locked(dev);
 259
 260         saved_enabled = crtc->enabled;
 261         crtc->enabled = drm_helper_crtc_in_use(crtc);
 262         if (!crtc->enabled)
 263                 return true;
 264
 265         adjusted_mode = drm_mode_duplicate(dev, mode);
 266         if (!adjusted_mode) {
 267                 crtc->enabled = saved_enabled;
 268                 return false;
 269         }
 270
 271         saved_mode = crtc->mode;
 272         saved_x = crtc->x;
 273         saved_y = crtc->y;
 274
 275         /* Update crtc values up front so the driver can rely on them for mode
 276          * setting.
 277          */
 278         crtc->mode = *mode;
 279         crtc->x = x;
 280         crtc->y = y;
 281
 282         /* Pass our mode to the connectors and the CRTC to give them a chance to
 283          * adjust it according to limitations or connector properties, and also
 284          * a chance to reject the mode entirely.
 285          */
 286         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 287
 288                 if (encoder->crtc != crtc)
 289                         continue;
 290
 291                 if (encoder->bridge && encoder->bridge->funcs->mode_fixup) {
 292                         ret = encoder->bridge->funcs->mode_fixup(
 293                                         encoder->bridge, mode, adjusted_mode);
 294                         if (!ret) {
 295                                 DRM_DEBUG_KMS("Bridge fixup failed\n");
 296                                 goto done;
 297                         }
 298                 }
 299
 300                 encoder_funcs = encoder->helper_private;
 301                 if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 302                                                       adjusted_mode))) {
 303                         DRM_DEBUG_KMS("Encoder fixup failed\n");
 304                         goto done;
 305                 }
 306         }
 307
 308         if (!(ret = crtc_funcs->mode_fixup(crtc, mode, adjusted_mode))) {
 309                 DRM_DEBUG_KMS("CRTC fixup failed\n");
 310                 goto done;
 311         }
 312         DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);
 313
 314         /* Prepare the encoders and CRTCs before setting the mode. */
 315         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 316
 317                 if (encoder->crtc != crtc)
 318                         continue;
 319
 320                 if (encoder->bridge)
 321                         encoder->bridge->funcs->disable(encoder->bridge);
 322
 323                 encoder_funcs = encoder->helper_private;
 324                 /* Disable the encoders as the first thing we do. */
 325                 encoder_funcs->prepare(encoder);
 326
 327                 if (encoder->bridge)
 328                         encoder->bridge->funcs->post_disable(encoder->bridge);
 329         }
 330
 331         drm_crtc_prepare_encoders(dev);
 332
 333         crtc_funcs->prepare(crtc);
 334
 335         /* Set up the DPLL and any encoders state that needs to adjust or depend
 336          * on the DPLL.
 337          */
 338         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 339         if (!ret)
 340             goto done;
 341
 342         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 343
 344                 if (encoder->crtc != crtc)
 345                         continue;
 346
 347                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
 348                         encoder->base.id, encoder->name,
 349                         mode->base.id, mode->name);
 350                 encoder_funcs = encoder->helper_private;
 351                 encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 352
 353                 if (encoder->bridge && encoder->bridge->funcs->mode_set)
 354                         encoder->bridge->funcs->mode_set(encoder->bridge, mode,
 355                                         adjusted_mode);
 356         }
 357
 358         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 359         crtc_funcs->commit(crtc);
 360
 361         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 362
 363                 if (encoder->crtc != crtc)
 364                         continue;
 365
 366                 if (encoder->bridge)
 367                         encoder->bridge->funcs->pre_enable(encoder->bridge);
 368
 369                 encoder_funcs = encoder->helper_private;
 370                 encoder_funcs->commit(encoder);
 371
 372                 if (encoder->bridge)
 373                         encoder->bridge->funcs->enable(encoder->bridge);
 374         }
 375
 376         /* Store real post-adjustment hardware mode. */
 377         crtc->hwmode = *adjusted_mode;
 378
 379         /* Calculate and store various constants which
 380          * are later needed by vblank and swap-completion
 381          * timestamping. They are derived from true hwmode.
 382          */
 383         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 384
 385         /* FIXME: add subpixel order */
 386 done:
 387         drm_mode_destroy(dev, adjusted_mode);
 388         if (!ret) {
 389                 crtc->enabled = saved_enabled;
 390                 crtc->mode = saved_mode;
 391                 crtc->x = saved_x;
 392                 crtc->y = saved_y;
 393         }
 394
 395         return ret;
 396 }
 397 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 398
 399 static void
 400 drm_crtc_helper_disable(struct drm_crtc *crtc)
 401 {
 402         struct drm_device *dev = crtc->dev;
 403         struct drm_connector *connector;
 404         struct drm_encoder *encoder;
 405
 406         /* Decouple all encoders and their attached connectors from this crtc */
 407         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 408                 if (encoder->crtc != crtc)
 409                         continue;
 410
 411                 list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 412                         if (connector->encoder != encoder)
 413                                 continue;
 414
 415                         connector->encoder = NULL;
 416
 417                         /*
 418                          * drm_helper_disable_unused_functions() ought to be
 419                          * doing this, but since we've decoupled the encoder
 420                          * from the connector above, the required connection
 421                          * between them is henceforth no longer available.
 422                          */
 423                         connector->dpms = DRM_MODE_DPMS_OFF;
 424                 }
 425         }
 426
 427         __drm_helper_disable_unused_functions(dev);
 428 }
 429
 430 /**
 431  * drm_crtc_helper_set_config - set a new config from userspace
 432  * @set: mode set configuration
 433  *
 434  * Setup a new configuration, provided by the upper layers (either an ioctl call
 435  * from userspace or internally e.g. from the fbdev support code) in @set, and
 436  * enable it. This is the main helper functions for drivers that implement
 437  * kernel mode setting with the crtc helper functions and the assorted
 438  * ->prepare(), ->modeset() and ->commit() helper callbacks.
 439  *
 440  * Returns:
 441  * Returns 0 on success, negative errno numbers on failure.
 442  */
 443 int drm_crtc_helper_set_config(struct drm_mode_set *set)
 444 {
 445         struct drm_device *dev;
 446         struct drm_crtc *new_crtc;
 447         struct drm_encoder *save_encoders, *new_encoder, *encoder;
 448         bool mode_changed = false; /* if true do a full mode set */
 449         bool fb_changed = false; /* if true and !mode_changed just do a flip */
 450         struct drm_connector *save_connectors, *connector;
 451         int count = 0, ro, fail = 0;
 452         struct drm_crtc_helper_funcs *crtc_funcs;
 453         struct drm_mode_set save_set;
 454         int ret;
 455         int i;
 456
 457         DRM_DEBUG_KMS("\n");
 458
 459         BUG_ON(!set);
 460         BUG_ON(!set->crtc);
 461         BUG_ON(!set->crtc->helper_private);
 462
 463         /* Enforce sane interface api - has been abused by the fb helper. */
 464         BUG_ON(!set->mode && set->fb);
 465         BUG_ON(set->fb && set->num_connectors == 0);
 466
 467         crtc_funcs = set->crtc->helper_private;
 468
 469         if (!set->mode)
 470                 set->fb = NULL;
 471
 472         if (set->fb) {
 473                 DRM_DEBUG_KMS("[CRTC:%d] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 474                                 set->crtc->base.id, set->fb->base.id,
 475                                 (int)set->num_connectors, set->x, set->y);
 476         } else {
 477                 DRM_DEBUG_KMS("[CRTC:%d] [NOFB]\n", set->crtc->base.id);
 478                 drm_crtc_helper_disable(set->crtc);
 479                 return 0;
 480         }
 481
 482         dev = set->crtc->dev;
 483
 484         drm_warn_on_modeset_not_all_locked(dev);
 485
 486         /*
 487          * Allocate space for the backup of all (non-pointer) encoder and
 488          * connector data.
 489          */
 490         save_encoders = kzalloc(dev->mode_config.num_encoder *
 491                                 sizeof(struct drm_encoder), GFP_KERNEL);
 492         if (!save_encoders)
 493                 return -ENOMEM;
 494
 495         save_connectors = kzalloc(dev->mode_config.num_connector *
 496                                 sizeof(struct drm_connector), GFP_KERNEL);
 497         if (!save_connectors) {
 498                 kfree(save_encoders);
 499                 return -ENOMEM;
 500         }
 501
 502         /*
 503          * Copy data. Note that driver private data is not affected.
 504          * Should anything bad happen only the expected state is
 505          * restored, not the drivers personal bookkeeping.
 506          */
 507         count = 0;
 508         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 509                 save_encoders[count++] = *encoder;
 510         }
 511
 512         count = 0;
 513         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 514                 save_connectors[count++] = *connector;
 515         }
 516
 517         save_set.crtc = set->crtc;
 518         save_set.mode = &set->crtc->mode;
 519         save_set.x = set->crtc->x;
 520         save_set.y = set->crtc->y;
 521         save_set.fb = set->crtc->primary->fb;
 522
 523         /* We should be able to check here if the fb has the same properties
 524          * and then just flip_or_move it */
 525         if (set->crtc->primary->fb != set->fb) {
 526                 /* If we have no fb then treat it as a full mode set */
 527                 if (set->crtc->primary->fb == NULL) {
 528                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 529                         mode_changed = true;
 530                 } else if (set->fb == NULL) {
 531                         mode_changed = true;
 532                 } else if (set->fb->pixel_format !=
 533                            set->crtc->primary->fb->pixel_format) {
 534                         mode_changed = true;
 535                 } else
 536                         fb_changed = true;
 537         }
 538
 539         if (set->x != set->crtc->x || set->y != set->crtc->y)
 540                 fb_changed = true;
 541
 542         if (set->mode && !drm_mode_equal(set->mode, &set->crtc->mode)) {
 543                 DRM_DEBUG_KMS("modes are different, full mode set\n");
 544                 drm_mode_debug_printmodeline(&set->crtc->mode);
 545                 drm_mode_debug_printmodeline(set->mode);
 546                 mode_changed = true;
 547         }
 548
 549         /* a) traverse passed in connector list and get encoders for them */
 550         count = 0;
 551         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 552                 struct drm_connector_helper_funcs *connector_funcs =
 553                         connector->helper_private;
 554                 new_encoder = connector->encoder;
 555                 for (ro = 0; ro < set->num_connectors; ro++) {
 556                         if (set->connectors[ro] == connector) {
 557                                 new_encoder = connector_funcs->best_encoder(connector);
 558                                 /* if we can't get an encoder for a connector
 559                                    we are setting now - then fail */
 560                                 if (new_encoder == NULL)
 561                                         /* don't break so fail path works correct */
 562                                         fail = 1;
 563
 564                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
 565                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 566                                         mode_changed = true;
 567                                 }
 568
 569                                 break;
 570                         }
 571                 }
 572
 573                 if (new_encoder != connector->encoder) {
 574                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 575                         mode_changed = true;
 576                         /* If the encoder is reused for another connector, then
 577                          * the appropriate crtc will be set later.
 578                          */
 579                         if (connector->encoder)
 580                                 connector->encoder->crtc = NULL;
 581                         connector->encoder = new_encoder;
 582                 }
 583         }
 584
 585         if (fail) {
 586                 ret = -EINVAL;
 587                 goto fail;
 588         }
 589
 590         count = 0;
 591         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 592                 if (!connector->encoder)
 593                         continue;
 594
 595                 if (connector->encoder->crtc == set->crtc)
 596                         new_crtc = NULL;
 597                 else
 598                         new_crtc = connector->encoder->crtc;
 599
 600                 for (ro = 0; ro < set->num_connectors; ro++) {
 601                         if (set->connectors[ro] == connector)
 602                                 new_crtc = set->crtc;
 603                 }
 604
 605                 /* Make sure the new CRTC will work with the encoder */
 606                 if (new_crtc &&
 607                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 608                         ret = -EINVAL;
 609                         goto fail;
 610                 }
 611                 if (new_crtc != connector->encoder->crtc) {
 612                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 613                         mode_changed = true;
 614                         connector->encoder->crtc = new_crtc;
 615                 }
 616                 if (new_crtc) {
 617                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d]\n",
 618                                 connector->base.id, connector->name,
 619                                 new_crtc->base.id);
 620                 } else {
 621                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 622                                 connector->base.id, connector->name);
 623                 }
 624         }
 625
 626         /* mode_set_base is not a required function */
 627         if (fb_changed && !crtc_funcs->mode_set_base)
 628                 mode_changed = true;
 629
 630         if (mode_changed) {
 631                 if (drm_helper_crtc_in_use(set->crtc)) {
 632                         DRM_DEBUG_KMS("attempting to set mode from"
 633                                         " userspace\n");
 634                         drm_mode_debug_printmodeline(set->mode);
 635                         set->crtc->primary->fb = set->fb;
 636                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 637                                                       set->x, set->y,
 638                                                       save_set.fb)) {
 639                                 DRM_ERROR("failed to set mode on [CRTC:%d]\n",
 640                                           set->crtc->base.id);
 641                                 set->crtc->primary->fb = save_set.fb;
 642                                 ret = -EINVAL;
 643                                 goto fail;
 644                         }
 645                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 646                         for (i = 0; i < set->num_connectors; i++) {
 647                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 648                                               set->connectors[i]->name);
 649                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 650                         }
 651                 }
 652                 __drm_helper_disable_unused_functions(dev);
 653         } else if (fb_changed) {
 654                 set->crtc->x = set->x;
 655                 set->crtc->y = set->y;
 656                 set->crtc->primary->fb = set->fb;
 657                 ret = crtc_funcs->mode_set_base(set->crtc,
 658                                                 set->x, set->y, save_set.fb);
 659                 if (ret != 0) {
 660                         set->crtc->x = save_set.x;
 661                         set->crtc->y = save_set.y;
 662                         set->crtc->primary->fb = save_set.fb;
 663                         goto fail;
 664                 }
 665         }
 666
 667         kfree(save_connectors);
 668         kfree(save_encoders);
 669         return 0;
 670
 671 fail:
 672         /* Restore all previous data. */
 673         count = 0;
 674         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 675                 *encoder = save_encoders[count++];
 676         }
 677
 678         count = 0;
 679         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 680                 *connector = save_connectors[count++];
 681         }
 682
 683         /* Try to restore the config */
 684         if (mode_changed &&
 685             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 686                                       save_set.y, save_set.fb))
 687                 DRM_ERROR("failed to restore config after modeset failure\n");
 688
 689         kfree(save_connectors);
 690         kfree(save_encoders);
 691         return ret;
 692 }
 693 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 694
 695 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 696 {
 697         int dpms = DRM_MODE_DPMS_OFF;
 698         struct drm_connector *connector;
 699         struct drm_device *dev = encoder->dev;
 700
 701         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 702                 if (connector->encoder == encoder)
 703                         if (connector->dpms < dpms)
 704                                 dpms = connector->dpms;
 705         return dpms;
 706 }
 707
 708 /* Helper which handles bridge ordering around encoder dpms */
 709 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 710 {
 711         struct drm_bridge *bridge = encoder->bridge;
 712         struct drm_encoder_helper_funcs *encoder_funcs;
 713
 714         if (bridge) {
 715                 if (mode == DRM_MODE_DPMS_ON)
 716                         bridge->funcs->pre_enable(bridge);
 717                 else
 718                         bridge->funcs->disable(bridge);
 719         }
 720
 721         encoder_funcs = encoder->helper_private;
 722         if (encoder_funcs->dpms)
 723                 encoder_funcs->dpms(encoder, mode);
 724
 725         if (bridge) {
 726                 if (mode == DRM_MODE_DPMS_ON)
 727                         bridge->funcs->enable(bridge);
 728                 else
 729                         bridge->funcs->post_disable(bridge);
 730         }
 731 }
 732
 733 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 734 {
 735         int dpms = DRM_MODE_DPMS_OFF;
 736         struct drm_connector *connector;
 737         struct drm_device *dev = crtc->dev;
 738
 739         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 740                 if (connector->encoder && connector->encoder->crtc == crtc)
 741                         if (connector->dpms < dpms)
 742                                 dpms = connector->dpms;
 743         return dpms;
 744 }
 745
 746 /**
 747  * drm_helper_connector_dpms() - connector dpms helper implementation
 748  * @connector: affected connector
 749  * @mode: DPMS mode
 750  *
 751  * This is the main helper function provided by the crtc helper framework for
 752  * implementing the DPMS connector attribute. It computes the new desired DPMS
 753  * state for all encoders and crtcs in the output mesh and calls the ->dpms()
 754  * callback provided by the driver appropriately.
 755  */
 756 void drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 757 {
 758         struct drm_encoder *encoder = connector->encoder;
 759         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 760         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 761
 762         if (mode == connector->dpms)
 763                 return;
 764
 765         old_dpms = connector->dpms;
 766         connector->dpms = mode;
 767
 768         if (encoder)
 769                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 770
 771         /* from off to on, do crtc then encoder */
 772         if (mode < old_dpms) {
 773                 if (crtc) {
 774                         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 775                         if (crtc_funcs->dpms)
 776                                 (*crtc_funcs->dpms) (crtc,
 777                                                      drm_helper_choose_crtc_dpms(crtc));
 778                 }
 779                 if (encoder)
 780                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 781         }
 782
 783         /* from on to off, do encoder then crtc */
 784         if (mode > old_dpms) {
 785                 if (encoder)
 786                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 787                 if (crtc) {
 788                         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 789                         if (crtc_funcs->dpms)
 790                                 (*crtc_funcs->dpms) (crtc,
 791                                                      drm_helper_choose_crtc_dpms(crtc));
 792                 }
 793         }
 794
 795         return;
 796 }
 797 EXPORT_SYMBOL(drm_helper_connector_dpms);
 798
 799 /**
 800  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
 801  * @fb: drm_framebuffer object to fill out
 802  * @mode_cmd: metadata from the userspace fb creation request
 803  *
 804  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
 805  * metadata fields.
 806  */
 807 void drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
 808                                     struct drm_mode_fb_cmd2 *mode_cmd)
 809 {
 810         int i;
 811
 812         fb->width = mode_cmd->width;
 813         fb->height = mode_cmd->height;
 814         for (i = 0; i < 4; i++) {
 815                 fb->pitches[i] = mode_cmd->pitches[i];
 816                 fb->offsets[i] = mode_cmd->offsets[i];
 817         }
 818         drm_fb_get_bpp_depth(mode_cmd->pixel_format, &fb->depth,
 819                                     &fb->bits_per_pixel);
 820         fb->pixel_format = mode_cmd->pixel_format;
 821 }
 822 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
 823
 824 /**
 825  * drm_helper_resume_force_mode - force-restore mode setting configuration
 826  * @dev: drm_device which should be restored
 827  *
 828  * Drivers which use the mode setting helpers can use this function to
 829  * force-restore the mode setting configuration e.g. on resume or when something
 830  * else might have trampled over the hw state (like some overzealous old BIOSen
 831  * tended to do).
 832  *
 833  * This helper doesn't provide a error return value since restoring the old
 834  * config should never fail due to resource allocation issues since the driver
 835  * has successfully set the restored configuration already. Hence this should
 836  * boil down to the equivalent of a few dpms on calls, which also don't provide
 837  * an error code.
 838  *
 839  * Drivers where simply restoring an old configuration again might fail (e.g.
 840  * due to slight differences in allocating shared resources when the
 841  * configuration is restored in a different order than when userspace set it up)
 842  * need to use their own restore logic.
 843  */
 844 void drm_helper_resume_force_mode(struct drm_device *dev)
 845 {
 846         struct drm_crtc *crtc;
 847         struct drm_encoder *encoder;
 848         struct drm_crtc_helper_funcs *crtc_funcs;
 849         int encoder_dpms;
 850         bool ret;
 851
 852         drm_modeset_lock_all(dev);
 853         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 854
 855                 if (!crtc->enabled)
 856                         continue;
 857
 858                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 859                                                crtc->x, crtc->y, crtc->primary->fb);
 860
 861                 /* Restoring the old config should never fail! */
 862                 if (ret == false)
 863                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 864
 865                 /* Turn off outputs that were already powered off */
 866                 if (drm_helper_choose_crtc_dpms(crtc)) {
 867                         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 868
 869                                 if(encoder->crtc != crtc)
 870                                         continue;
 871
 872                                 encoder_dpms = drm_helper_choose_encoder_dpms(
 873                                                         encoder);
 874
 875                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
 876                         }
 877
 878                         crtc_funcs = crtc->helper_private;
 879                         if (crtc_funcs->dpms)
 880                                 (*crtc_funcs->dpms) (crtc,
 881                                                      drm_helper_choose_crtc_dpms(crtc));
 882                 }
 883         }
 884
 885         /* disable the unused connectors while restoring the modesetting */
 886         __drm_helper_disable_unused_functions(dev);
 887         drm_modeset_unlock_all(dev);
 888 }
 889 EXPORT_SYMBOL(drm_helper_resume_force_mode);