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