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_atomic.h>
  37 #include <drm/drm_crtc.h>
  38 #include <drm/drm_crtc_helper.h>
  39 #include <drm/drm_fb_helper.h>
  40 #include <drm/drm_plane_helper.h>
  41 #include <drm/drm_atomic_helper.h>
  42 #include <drm/drm_edid.h>
  43
  44 /**
  45  * DOC: overview
  46  *
  47  * The CRTC modeset helper library provides a default set_config implementation
  48  * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
  49  * the same callbacks which drivers can use to e.g. restore the modeset
  50  * configuration on resume with drm_helper_resume_force_mode().
  51  *
  52  * The driver callbacks are mostly compatible with the atomic modeset helpers,
  53  * except for the handling of the primary plane: Atomic helpers require that the
  54  * primary plane is implemented as a real standalone plane and not directly tied
  55  * to the CRTC state. For easier transition this library provides functions to
  56  * implement the old semantics required by the CRTC helpers using the new plane
  57  * and atomic helper callbacks.
  58  *
  59  * Drivers are strongly urged to convert to the atomic helpers (by way of first
  60  * converting to the plane helpers). New drivers must not use these functions
  61  * but need to implement the atomic interface instead, potentially using the
  62  * atomic helpers for that.
  63  */
  64 MODULE_AUTHOR("David Airlie, Jesse Barnes");
  65 MODULE_DESCRIPTION("DRM KMS helper");
  66
  67 /**
  68  * drm_helper_move_panel_connectors_to_head() - move panels to the front in the
  69  *                                              connector list
  70  * @dev: drm device to operate on
  71  *
  72  * Some userspace presumes that the first connected connector is the main
  73  * display, where it's supposed to display e.g. the login screen. For
  74  * laptops, this should be the main panel. Use this function to sort all
  75  * (eDP/LVDS) panels to the front of the connector list, instead of
  76  * painstakingly trying to initialize them in the right order.
  77  */
  78 void drm_helper_move_panel_connectors_to_head(struct drm_device *dev)
  79 {
  80         struct drm_connector *connector, *tmp;
  81         struct list_head panel_list;
  82
  83         INIT_LIST_HEAD(&panel_list);
  84
  85         list_for_each_entry_safe(connector, tmp,
  86                                  &dev->mode_config.connector_list, head) {
  87                 if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
  88                     connector->connector_type == DRM_MODE_CONNECTOR_eDP)
  89                         list_move_tail(&connector->head, &panel_list);
  90         }
  91
  92         list_splice(&panel_list, &dev->mode_config.connector_list);
  93 }
  94 EXPORT_SYMBOL(drm_helper_move_panel_connectors_to_head);
  95
  96 /**
  97  * drm_helper_encoder_in_use - check if a given encoder is in use
  98  * @encoder: encoder to check
  99  *
 100  * Checks whether @encoder is with the current mode setting output configuration
 101  * in use by any connector. This doesn't mean that it is actually enabled since
 102  * the DPMS state is tracked separately.
 103  *
 104  * Returns:
 105  * True if @encoder is used, false otherwise.
 106  */
 107 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
 108 {
 109         struct drm_connector *connector;
 110         struct drm_device *dev = encoder->dev;
 111
 112         WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 113         WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 114         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 115                 if (connector->encoder == encoder)
 116                         return true;
 117         return false;
 118 }
 119 EXPORT_SYMBOL(drm_helper_encoder_in_use);
 120
 121 /**
 122  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 123  * @crtc: CRTC to check
 124  *
 125  * Checks whether @crtc is with the current mode setting output configuration
 126  * in use by any connector. This doesn't mean that it is actually enabled since
 127  * the DPMS state is tracked separately.
 128  *
 129  * Returns:
 130  * True if @crtc is used, false otherwise.
 131  */
 132 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 133 {
 134         struct drm_encoder *encoder;
 135         struct drm_device *dev = crtc->dev;
 136
 137         WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 138         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
 139                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 140                         return true;
 141         return false;
 142 }
 143 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 144
 145 static void
 146 drm_encoder_disable(struct drm_encoder *encoder)
 147 {
 148         const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 149
 150         drm_bridge_disable(encoder->bridge);
 151
 152         if (encoder_funcs->disable)
 153                 (*encoder_funcs->disable)(encoder);
 154         else
 155                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 156
 157         drm_bridge_post_disable(encoder->bridge);
 158 }
 159
 160 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 161 {
 162         struct drm_encoder *encoder;
 163         struct drm_crtc *crtc;
 164
 165         drm_warn_on_modeset_not_all_locked(dev);
 166
 167         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 168                 if (!drm_helper_encoder_in_use(encoder)) {
 169                         drm_encoder_disable(encoder);
 170                         /* disconnect encoder from any connector */
 171                         encoder->crtc = NULL;
 172                 }
 173         }
 174
 175         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 176                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 177                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 178                 if (!crtc->enabled) {
 179                         if (crtc_funcs->disable)
 180                                 (*crtc_funcs->disable)(crtc);
 181                         else
 182                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 183                         crtc->primary->fb = NULL;
 184                 }
 185         }
 186 }
 187
 188 /**
 189  * drm_helper_disable_unused_functions - disable unused objects
 190  * @dev: DRM device
 191  *
 192  * This function walks through the entire mode setting configuration of @dev. It
 193  * will remove any crtc links of unused encoders and encoder links of
 194  * disconnected connectors. Then it will disable all unused encoders and crtcs
 195  * either by calling their disable callback if available or by calling their
 196  * dpms callback with DRM_MODE_DPMS_OFF.
 197  */
 198 void drm_helper_disable_unused_functions(struct drm_device *dev)
 199 {
 200         drm_modeset_lock_all(dev);
 201         __drm_helper_disable_unused_functions(dev);
 202         drm_modeset_unlock_all(dev);
 203 }
 204 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 205
 206 /*
 207  * Check the CRTC we're going to map each output to vs. its current
 208  * CRTC.  If they don't match, we have to disable the output and the CRTC
 209  * since the driver will have to re-route things.
 210  */
 211 static void
 212 drm_crtc_prepare_encoders(struct drm_device *dev)
 213 {
 214         const struct drm_encoder_helper_funcs *encoder_funcs;
 215         struct drm_encoder *encoder;
 216
 217         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 218                 encoder_funcs = encoder->helper_private;
 219                 /* Disable unused encoders */
 220                 if (encoder->crtc == NULL)
 221                         drm_encoder_disable(encoder);
 222                 /* Disable encoders whose CRTC is about to change */
 223                 if (encoder_funcs->get_crtc &&
 224                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
 225                         drm_encoder_disable(encoder);
 226         }
 227 }
 228
 229 /**
 230  * drm_crtc_helper_set_mode - internal helper to set a mode
 231  * @crtc: CRTC to program
 232  * @mode: mode to use
 233  * @x: horizontal offset into the surface
 234  * @y: vertical offset into the surface
 235  * @old_fb: old framebuffer, for cleanup
 236  *
 237  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 238  * to fixup or reject the mode prior to trying to set it. This is an internal
 239  * helper that drivers could e.g. use to update properties that require the
 240  * entire output pipe to be disabled and re-enabled in a new configuration. For
 241  * example for changing whether audio is enabled on a hdmi link or for changing
 242  * panel fitter or dither attributes. It is also called by the
 243  * drm_crtc_helper_set_config() helper function to drive the mode setting
 244  * sequence.
 245  *
 246  * Returns:
 247  * True if the mode was set successfully, false otherwise.
 248  */
 249 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 250                               struct drm_display_mode *mode,
 251                               int x, int y,
 252                               struct drm_framebuffer *old_fb)
 253 {
 254         struct drm_device *dev = crtc->dev;
 255         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
 256         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 257         const struct drm_encoder_helper_funcs *encoder_funcs;
 258         int saved_x, saved_y;
 259         bool saved_enabled;
 260         struct drm_encoder *encoder;
 261         bool ret = true;
 262
 263         drm_warn_on_modeset_not_all_locked(dev);
 264
 265         saved_enabled = crtc->enabled;
 266         crtc->enabled = drm_helper_crtc_in_use(crtc);
 267         if (!crtc->enabled)
 268                 return true;
 269
 270         adjusted_mode = drm_mode_duplicate(dev, mode);
 271         if (!adjusted_mode) {
 272                 crtc->enabled = saved_enabled;
 273                 return false;
 274         }
 275
 276         saved_mode = crtc->mode;
 277         saved_hwmode = crtc->hwmode;
 278         saved_x = crtc->x;
 279         saved_y = crtc->y;
 280
 281         /* Update crtc values up front so the driver can rely on them for mode
 282          * setting.
 283          */
 284         crtc->mode = *mode;
 285         crtc->x = x;
 286         crtc->y = y;
 287
 288         /* Pass our mode to the connectors and the CRTC to give them a chance to
 289          * adjust it according to limitations or connector properties, and also
 290          * a chance to reject the mode entirely.
 291          */
 292         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 293
 294                 if (encoder->crtc != crtc)
 295                         continue;
 296
 297                 ret = drm_bridge_mode_fixup(encoder->bridge,
 298                         mode, adjusted_mode);
 299                 if (!ret) {
 300                         DRM_DEBUG_KMS("Bridge fixup failed\n");
 301                         goto done;
 302                 }
 303
 304                 encoder_funcs = encoder->helper_private;
 305                 if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 306                                                       adjusted_mode))) {
 307                         DRM_DEBUG_KMS("Encoder fixup failed\n");
 308                         goto done;
 309                 }
 310         }
 311
 312         if (!(ret = crtc_funcs->mode_fixup(crtc, mode, adjusted_mode))) {
 313                 DRM_DEBUG_KMS("CRTC fixup failed\n");
 314                 goto done;
 315         }
 316         DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);
 317
 318         crtc->hwmode = *adjusted_mode;
 319
 320         /* Prepare the encoders and CRTCs before setting the mode. */
 321         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 322
 323                 if (encoder->crtc != crtc)
 324                         continue;
 325
 326                 drm_bridge_disable(encoder->bridge);
 327
 328                 encoder_funcs = encoder->helper_private;
 329                 /* Disable the encoders as the first thing we do. */
 330                 encoder_funcs->prepare(encoder);
 331
 332                 drm_bridge_post_disable(encoder->bridge);
 333         }
 334
 335         drm_crtc_prepare_encoders(dev);
 336
 337         crtc_funcs->prepare(crtc);
 338
 339         /* Set up the DPLL and any encoders state that needs to adjust or depend
 340          * on the DPLL.
 341          */
 342         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 343         if (!ret)
 344             goto done;
 345
 346         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 347
 348                 if (encoder->crtc != crtc)
 349                         continue;
 350
 351                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
 352                         encoder->base.id, encoder->name,
 353                         mode->base.id, mode->name);
 354                 encoder_funcs = encoder->helper_private;
 355                 encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 356
 357                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
 358         }
 359
 360         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 361         crtc_funcs->commit(crtc);
 362
 363         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 364
 365                 if (encoder->crtc != crtc)
 366                         continue;
 367
 368                 drm_bridge_pre_enable(encoder->bridge);
 369
 370                 encoder_funcs = encoder->helper_private;
 371                 encoder_funcs->commit(encoder);
 372
 373                 drm_bridge_enable(encoder->bridge);
 374         }
 375
 376         /* Calculate and store various constants which
 377          * are later needed by vblank and swap-completion
 378          * timestamping. They are derived from true hwmode.
 379          */
 380         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 381
 382         /* FIXME: add subpixel order */
 383 done:
 384         drm_mode_destroy(dev, adjusted_mode);
 385         if (!ret) {
 386                 crtc->enabled = saved_enabled;
 387                 crtc->mode = saved_mode;
 388                 crtc->hwmode = saved_hwmode;
 389                 crtc->x = saved_x;
 390                 crtc->y = saved_y;
 391         }
 392
 393         return ret;
 394 }
 395 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 396
 397 static void
 398 drm_crtc_helper_disable(struct drm_crtc *crtc)
 399 {
 400         struct drm_device *dev = crtc->dev;
 401         struct drm_connector *connector;
 402         struct drm_encoder *encoder;
 403
 404         /* Decouple all encoders and their attached connectors from this crtc */
 405         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 406                 if (encoder->crtc != crtc)
 407                         continue;
 408
 409                 list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 410                         if (connector->encoder != encoder)
 411                                 continue;
 412
 413                         connector->encoder = NULL;
 414
 415                         /*
 416                          * drm_helper_disable_unused_functions() ought to be
 417                          * doing this, but since we've decoupled the encoder
 418                          * from the connector above, the required connection
 419                          * between them is henceforth no longer available.
 420                          */
 421                         connector->dpms = DRM_MODE_DPMS_OFF;
 422                 }
 423         }
 424
 425         __drm_helper_disable_unused_functions(dev);
 426 }
 427
 428 /**
 429  * drm_crtc_helper_set_config - set a new config from userspace
 430  * @set: mode set configuration
 431  *
 432  * Setup a new configuration, provided by the upper layers (either an ioctl call
 433  * from userspace or internally e.g. from the fbdev support code) in @set, and
 434  * enable it. This is the main helper functions for drivers that implement
 435  * kernel mode setting with the crtc helper functions and the assorted
 436  * ->prepare(), ->modeset() and ->commit() helper callbacks.
 437  *
 438  * Returns:
 439  * Returns 0 on success, negative errno numbers on failure.
 440  */
 441 int drm_crtc_helper_set_config(struct drm_mode_set *set)
 442 {
 443         struct drm_device *dev;
 444         struct drm_crtc *new_crtc;
 445         struct drm_encoder *save_encoders, *new_encoder, *encoder;
 446         bool mode_changed = false; /* if true do a full mode set */
 447         bool fb_changed = false; /* if true and !mode_changed just do a flip */
 448         struct drm_connector *save_connectors, *connector;
 449         int count = 0, ro, fail = 0;
 450         const struct drm_crtc_helper_funcs *crtc_funcs;
 451         struct drm_mode_set save_set;
 452         int ret;
 453         int i;
 454
 455         DRM_DEBUG_KMS("\n");
 456
 457         BUG_ON(!set);
 458         BUG_ON(!set->crtc);
 459         BUG_ON(!set->crtc->helper_private);
 460
 461         /* Enforce sane interface api - has been abused by the fb helper. */
 462         BUG_ON(!set->mode && set->fb);
 463         BUG_ON(set->fb && set->num_connectors == 0);
 464
 465         crtc_funcs = set->crtc->helper_private;
 466
 467         if (!set->mode)
 468                 set->fb = NULL;
 469
 470         if (set->fb) {
 471                 DRM_DEBUG_KMS("[CRTC:%d] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 472                                 set->crtc->base.id, set->fb->base.id,
 473                                 (int)set->num_connectors, set->x, set->y);
 474         } else {
 475                 DRM_DEBUG_KMS("[CRTC:%d] [NOFB]\n", set->crtc->base.id);
 476                 drm_crtc_helper_disable(set->crtc);
 477                 return 0;
 478         }
 479
 480         dev = set->crtc->dev;
 481
 482         drm_warn_on_modeset_not_all_locked(dev);
 483
 484         /*
 485          * Allocate space for the backup of all (non-pointer) encoder and
 486          * connector data.
 487          */
 488         save_encoders = kzalloc(dev->mode_config.num_encoder *
 489                                 sizeof(struct drm_encoder), GFP_KERNEL);
 490         if (!save_encoders)
 491                 return -ENOMEM;
 492
 493         save_connectors = kzalloc(dev->mode_config.num_connector *
 494                                 sizeof(struct drm_connector), GFP_KERNEL);
 495         if (!save_connectors) {
 496                 kfree(save_encoders);
 497                 return -ENOMEM;
 498         }
 499
 500         /*
 501          * Copy data. Note that driver private data is not affected.
 502          * Should anything bad happen only the expected state is
 503          * restored, not the drivers personal bookkeeping.
 504          */
 505         count = 0;
 506         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 507                 save_encoders[count++] = *encoder;
 508         }
 509
 510         count = 0;
 511         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 512                 save_connectors[count++] = *connector;
 513         }
 514
 515         save_set.crtc = set->crtc;
 516         save_set.mode = &set->crtc->mode;
 517         save_set.x = set->crtc->x;
 518         save_set.y = set->crtc->y;
 519         save_set.fb = set->crtc->primary->fb;
 520
 521         /* We should be able to check here if the fb has the same properties
 522          * and then just flip_or_move it */
 523         if (set->crtc->primary->fb != set->fb) {
 524                 /* If we have no fb then treat it as a full mode set */
 525                 if (set->crtc->primary->fb == NULL) {
 526                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 527                         mode_changed = true;
 528                 } else if (set->fb == NULL) {
 529                         mode_changed = true;
 530                 } else if (set->fb->pixel_format !=
 531                            set->crtc->primary->fb->pixel_format) {
 532                         mode_changed = true;
 533                 } else
 534                         fb_changed = true;
 535         }
 536
 537         if (set->x != set->crtc->x || set->y != set->crtc->y)
 538                 fb_changed = true;
 539
 540         if (set->mode && !drm_mode_equal(set->mode, &set->crtc->mode)) {
 541                 DRM_DEBUG_KMS("modes are different, full mode set\n");
 542                 drm_mode_debug_printmodeline(&set->crtc->mode);
 543                 drm_mode_debug_printmodeline(set->mode);
 544                 mode_changed = true;
 545         }
 546
 547         /* a) traverse passed in connector list and get encoders for them */
 548         count = 0;
 549         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 550                 const struct drm_connector_helper_funcs *connector_funcs =
 551                         connector->helper_private;
 552                 new_encoder = connector->encoder;
 553                 for (ro = 0; ro < set->num_connectors; ro++) {
 554                         if (set->connectors[ro] == connector) {
 555                                 new_encoder = connector_funcs->best_encoder(connector);
 556                                 /* if we can't get an encoder for a connector
 557                                    we are setting now - then fail */
 558                                 if (new_encoder == NULL)
 559                                         /* don't break so fail path works correct */
 560                                         fail = 1;
 561
 562                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
 563                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 564                                         mode_changed = true;
 565                                 }
 566
 567                                 break;
 568                         }
 569                 }
 570
 571                 if (new_encoder != connector->encoder) {
 572                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 573                         mode_changed = true;
 574                         /* If the encoder is reused for another connector, then
 575                          * the appropriate crtc will be set later.
 576                          */
 577                         if (connector->encoder)
 578                                 connector->encoder->crtc = NULL;
 579                         connector->encoder = new_encoder;
 580                 }
 581         }
 582
 583         if (fail) {
 584                 ret = -EINVAL;
 585                 goto fail;
 586         }
 587
 588         count = 0;
 589         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 590                 if (!connector->encoder)
 591                         continue;
 592
 593                 if (connector->encoder->crtc == set->crtc)
 594                         new_crtc = NULL;
 595                 else
 596                         new_crtc = connector->encoder->crtc;
 597
 598                 for (ro = 0; ro < set->num_connectors; ro++) {
 599                         if (set->connectors[ro] == connector)
 600                                 new_crtc = set->crtc;
 601                 }
 602
 603                 /* Make sure the new CRTC will work with the encoder */
 604                 if (new_crtc &&
 605                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 606                         ret = -EINVAL;
 607                         goto fail;
 608                 }
 609                 if (new_crtc != connector->encoder->crtc) {
 610                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 611                         mode_changed = true;
 612                         connector->encoder->crtc = new_crtc;
 613                 }
 614                 if (new_crtc) {
 615                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d]\n",
 616                                 connector->base.id, connector->name,
 617                                 new_crtc->base.id);
 618                 } else {
 619                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 620                                 connector->base.id, connector->name);
 621                 }
 622         }
 623
 624         /* mode_set_base is not a required function */
 625         if (fb_changed && !crtc_funcs->mode_set_base)
 626                 mode_changed = true;
 627
 628         if (mode_changed) {
 629                 if (drm_helper_crtc_in_use(set->crtc)) {
 630                         DRM_DEBUG_KMS("attempting to set mode from"
 631                                         " userspace\n");
 632                         drm_mode_debug_printmodeline(set->mode);
 633                         set->crtc->primary->fb = set->fb;
 634                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 635                                                       set->x, set->y,
 636                                                       save_set.fb)) {
 637                                 DRM_ERROR("failed to set mode on [CRTC:%d]\n",
 638                                           set->crtc->base.id);
 639                                 set->crtc->primary->fb = save_set.fb;
 640                                 ret = -EINVAL;
 641                                 goto fail;
 642                         }
 643                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 644                         for (i = 0; i < set->num_connectors; i++) {
 645                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 646                                               set->connectors[i]->name);
 647                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 648                         }
 649                 }
 650                 __drm_helper_disable_unused_functions(dev);
 651         } else if (fb_changed) {
 652                 set->crtc->x = set->x;
 653                 set->crtc->y = set->y;
 654                 set->crtc->primary->fb = set->fb;
 655                 ret = crtc_funcs->mode_set_base(set->crtc,
 656                                                 set->x, set->y, save_set.fb);
 657                 if (ret != 0) {
 658                         set->crtc->x = save_set.x;
 659                         set->crtc->y = save_set.y;
 660                         set->crtc->primary->fb = save_set.fb;
 661                         goto fail;
 662                 }
 663         }
 664
 665         kfree(save_connectors);
 666         kfree(save_encoders);
 667         return 0;
 668
 669 fail:
 670         /* Restore all previous data. */
 671         count = 0;
 672         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 673                 *encoder = save_encoders[count++];
 674         }
 675
 676         count = 0;
 677         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 678                 *connector = save_connectors[count++];
 679         }
 680
 681         /* Try to restore the config */
 682         if (mode_changed &&
 683             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 684                                       save_set.y, save_set.fb))
 685                 DRM_ERROR("failed to restore config after modeset failure\n");
 686
 687         kfree(save_connectors);
 688         kfree(save_encoders);
 689         return ret;
 690 }
 691 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 692
 693 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 694 {
 695         int dpms = DRM_MODE_DPMS_OFF;
 696         struct drm_connector *connector;
 697         struct drm_device *dev = encoder->dev;
 698
 699         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 700                 if (connector->encoder == encoder)
 701                         if (connector->dpms < dpms)
 702                                 dpms = connector->dpms;
 703         return dpms;
 704 }
 705
 706 /* Helper which handles bridge ordering around encoder dpms */
 707 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 708 {
 709         struct drm_bridge *bridge = encoder->bridge;
 710         const struct drm_encoder_helper_funcs *encoder_funcs;
 711
 712         if (mode == DRM_MODE_DPMS_ON)
 713                 drm_bridge_pre_enable(bridge);
 714         else
 715                 drm_bridge_disable(bridge);
 716
 717         encoder_funcs = encoder->helper_private;
 718         if (encoder_funcs->dpms)
 719                 encoder_funcs->dpms(encoder, mode);
 720
 721         if (mode == DRM_MODE_DPMS_ON)
 722                 drm_bridge_enable(bridge);
 723         else
 724                 drm_bridge_post_disable(bridge);
 725 }
 726
 727 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 728 {
 729         int dpms = DRM_MODE_DPMS_OFF;
 730         struct drm_connector *connector;
 731         struct drm_device *dev = crtc->dev;
 732
 733         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 734                 if (connector->encoder && connector->encoder->crtc == crtc)
 735                         if (connector->dpms < dpms)
 736                                 dpms = connector->dpms;
 737         return dpms;
 738 }
 739
 740 /**
 741  * drm_helper_connector_dpms() - connector dpms helper implementation
 742  * @connector: affected connector
 743  * @mode: DPMS mode
 744  *
 745  * This is the main helper function provided by the crtc helper framework for
 746  * implementing the DPMS connector attribute. It computes the new desired DPMS
 747  * state for all encoders and crtcs in the output mesh and calls the ->dpms()
 748  * callback provided by the driver appropriately.
 749  */
 750 void drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 751 {
 752         struct drm_encoder *encoder = connector->encoder;
 753         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 754         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 755
 756         if (mode == connector->dpms)
 757                 return;
 758
 759         old_dpms = connector->dpms;
 760         connector->dpms = mode;
 761
 762         if (encoder)
 763                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 764
 765         /* from off to on, do crtc then encoder */
 766         if (mode < old_dpms) {
 767                 if (crtc) {
 768                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 769                         if (crtc_funcs->dpms)
 770                                 (*crtc_funcs->dpms) (crtc,
 771                                                      drm_helper_choose_crtc_dpms(crtc));
 772                 }
 773                 if (encoder)
 774                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 775         }
 776
 777         /* from on to off, do encoder then crtc */
 778         if (mode > old_dpms) {
 779                 if (encoder)
 780                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 781                 if (crtc) {
 782                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 783                         if (crtc_funcs->dpms)
 784                                 (*crtc_funcs->dpms) (crtc,
 785                                                      drm_helper_choose_crtc_dpms(crtc));
 786                 }
 787         }
 788
 789         return;
 790 }
 791 EXPORT_SYMBOL(drm_helper_connector_dpms);
 792
 793 /**
 794  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
 795  * @fb: drm_framebuffer object to fill out
 796  * @mode_cmd: metadata from the userspace fb creation request
 797  *
 798  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
 799  * metadata fields.
 800  */
 801 void drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
 802                                     struct drm_mode_fb_cmd2 *mode_cmd)
 803 {
 804         int i;
 805
 806         fb->width = mode_cmd->width;
 807         fb->height = mode_cmd->height;
 808         for (i = 0; i < 4; i++) {
 809                 fb->pitches[i] = mode_cmd->pitches[i];
 810                 fb->offsets[i] = mode_cmd->offsets[i];
 811                 fb->modifier[i] = mode_cmd->modifier[i];
 812         }
 813         drm_fb_get_bpp_depth(mode_cmd->pixel_format, &fb->depth,
 814                                     &fb->bits_per_pixel);
 815         fb->pixel_format = mode_cmd->pixel_format;
 816         fb->flags = mode_cmd->flags;
 817 }
 818 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
 819
 820 /**
 821  * drm_helper_resume_force_mode - force-restore mode setting configuration
 822  * @dev: drm_device which should be restored
 823  *
 824  * Drivers which use the mode setting helpers can use this function to
 825  * force-restore the mode setting configuration e.g. on resume or when something
 826  * else might have trampled over the hw state (like some overzealous old BIOSen
 827  * tended to do).
 828  *
 829  * This helper doesn't provide a error return value since restoring the old
 830  * config should never fail due to resource allocation issues since the driver
 831  * has successfully set the restored configuration already. Hence this should
 832  * boil down to the equivalent of a few dpms on calls, which also don't provide
 833  * an error code.
 834  *
 835  * Drivers where simply restoring an old configuration again might fail (e.g.
 836  * due to slight differences in allocating shared resources when the
 837  * configuration is restored in a different order than when userspace set it up)
 838  * need to use their own restore logic.
 839  */
 840 void drm_helper_resume_force_mode(struct drm_device *dev)
 841 {
 842         struct drm_crtc *crtc;
 843         struct drm_encoder *encoder;
 844         const struct drm_crtc_helper_funcs *crtc_funcs;
 845         int encoder_dpms;
 846         bool ret;
 847
 848         drm_modeset_lock_all(dev);
 849         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 850
 851                 if (!crtc->enabled)
 852                         continue;
 853
 854                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 855                                                crtc->x, crtc->y, crtc->primary->fb);
 856
 857                 /* Restoring the old config should never fail! */
 858                 if (ret == false)
 859                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 860
 861                 /* Turn off outputs that were already powered off */
 862                 if (drm_helper_choose_crtc_dpms(crtc)) {
 863                         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 864
 865                                 if(encoder->crtc != crtc)
 866                                         continue;
 867
 868                                 encoder_dpms = drm_helper_choose_encoder_dpms(
 869                                                         encoder);
 870
 871                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
 872                         }
 873
 874                         crtc_funcs = crtc->helper_private;
 875                         if (crtc_funcs->dpms)
 876                                 (*crtc_funcs->dpms) (crtc,
 877                                                      drm_helper_choose_crtc_dpms(crtc));
 878                 }
 879         }
 880
 881         /* disable the unused connectors while restoring the modesetting */
 882         __drm_helper_disable_unused_functions(dev);
 883         drm_modeset_unlock_all(dev);
 884 }
 885 EXPORT_SYMBOL(drm_helper_resume_force_mode);
 886
 887 /**
 888  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
 889  * @crtc: DRM CRTC
 890  * @mode: DRM display mode which userspace requested
 891  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
 892  * @x: x offset of the CRTC scanout area on the underlying framebuffer
 893  * @y: y offset of the CRTC scanout area on the underlying framebuffer
 894  * @old_fb: previous framebuffer
 895  *
 896  * This function implements a callback useable as the ->mode_set callback
 897  * required by the crtc helpers. Besides the atomic plane helper functions for
 898  * the primary plane the driver must also provide the ->mode_set_nofb callback
 899  * to set up the crtc.
 900  *
 901  * This is a transitional helper useful for converting drivers to the atomic
 902  * interfaces.
 903  */
 904 int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
 905                              struct drm_display_mode *adjusted_mode, int x, int y,
 906                              struct drm_framebuffer *old_fb)
 907 {
 908         struct drm_crtc_state *crtc_state;
 909         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 910         int ret;
 911
 912         if (crtc->funcs->atomic_duplicate_state)
 913                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
 914         else {
 915                 crtc_state = kzalloc(sizeof(*crtc_state), GFP_KERNEL);
 916                 if (!crtc_state)
 917                         return -ENOMEM;
 918                 if (crtc->state)
 919                         __drm_atomic_helper_crtc_duplicate_state(crtc, crtc_state);
 920                 else
 921                         crtc_state->crtc = crtc;
 922         }
 923
 924         crtc_state->planes_changed = true;
 925         crtc_state->mode_changed = true;
 926         ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
 927         if (ret)
 928                 goto out;
 929         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
 930
 931         if (crtc_funcs->atomic_check) {
 932                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
 933                 if (ret)
 934                         goto out;
 935         }
 936
 937         swap(crtc->state, crtc_state);
 938
 939         crtc_funcs->mode_set_nofb(crtc);
 940
 941         ret = drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
 942
 943 out:
 944         if (crtc->funcs->atomic_destroy_state)
 945                 crtc->funcs->atomic_destroy_state(crtc, crtc_state);
 946         else {
 947                 __drm_atomic_helper_crtc_destroy_state(crtc, crtc_state);
 948                 kfree(crtc_state);
 949         }
 950
 951         return ret;
 952 }
 953 EXPORT_SYMBOL(drm_helper_crtc_mode_set);
 954
 955 /**
 956  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
 957  * @crtc: DRM CRTC
 958  * @x: x offset of the CRTC scanout area on the underlying framebuffer
 959  * @y: y offset of the CRTC scanout area on the underlying framebuffer
 960  * @old_fb: previous framebuffer
 961  *
 962  * This function implements a callback useable as the ->mode_set_base used
 963  * required by the crtc helpers. The driver must provide the atomic plane helper
 964  * functions for the primary plane.
 965  *
 966  * This is a transitional helper useful for converting drivers to the atomic
 967  * interfaces.
 968  */
 969 int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
 970                                   struct drm_framebuffer *old_fb)
 971 {
 972         struct drm_plane_state *plane_state;
 973         struct drm_plane *plane = crtc->primary;
 974
 975         if (plane->funcs->atomic_duplicate_state)
 976                 plane_state = plane->funcs->atomic_duplicate_state(plane);
 977         else if (plane->state)
 978                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
 979         else
 980                 plane_state = kzalloc(sizeof(*plane_state), GFP_KERNEL);
 981         if (!plane_state)
 982                 return -ENOMEM;
 983         plane_state->plane = plane;
 984
 985         plane_state->crtc = crtc;
 986         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
 987         plane_state->crtc_x = 0;
 988         plane_state->crtc_y = 0;
 989         plane_state->crtc_h = crtc->mode.vdisplay;
 990         plane_state->crtc_w = crtc->mode.hdisplay;
 991         plane_state->src_x = x << 16;
 992         plane_state->src_y = y << 16;
 993         plane_state->src_h = crtc->mode.vdisplay << 16;
 994         plane_state->src_w = crtc->mode.hdisplay << 16;
 995
 996         return drm_plane_helper_commit(plane, plane_state, old_fb);
 997 }
 998 EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);