drivers/gpu/drm/drm_crtc_helper.c

   1 /*
   2  * Copyright (c) 2006-2008 Intel Corporation
   3  * Copyright (c) 2007 Dave Airlie <[email protected]>
   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 <[email protected]>
  28  *      Dave Airlie <[email protected]>
  29  *      Jesse Barnes <[email protected]>
  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_atomic.h>
  38 #include <drm/drm_crtc.h>
  39 #include <drm/drm_fourcc.h>
  40 #include <drm/drm_crtc_helper.h>
  41 #include <drm/drm_fb_helper.h>
  42 #include <drm/drm_plane_helper.h>
  43 #include <drm/drm_atomic_helper.h>
  44 #include <drm/drm_edid.h>
  45
  46 /**
  47  * DOC: overview
  48  *
  49  * The CRTC modeset helper library provides a default set_config implementation
  50  * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
  51  * the same callbacks which drivers can use to e.g. restore the modeset
  52  * configuration on resume with drm_helper_resume_force_mode().
  53  *
  54  * The driver callbacks are mostly compatible with the atomic modeset helpers,
  55  * except for the handling of the primary plane: Atomic helpers require that the
  56  * primary plane is implemented as a real standalone plane and not directly tied
  57  * to the CRTC state. For easier transition this library provides functions to
  58  * implement the old semantics required by the CRTC helpers using the new plane
  59  * and atomic helper callbacks.
  60  *
  61  * Drivers are strongly urged to convert to the atomic helpers (by way of first
  62  * converting to the plane helpers). New drivers must not use these functions
  63  * but need to implement the atomic interface instead, potentially using the
  64  * atomic helpers for that.
  65  */
  66 MODULE_AUTHOR("David Airlie, Jesse Barnes");
  67 MODULE_DESCRIPTION("DRM KMS helper");
  68 MODULE_LICENSE("GPL and additional rights");
  69
  70 /**
  71  * drm_helper_move_panel_connectors_to_head() - move panels to the front in the
  72  *                                              connector list
  73  * @dev: drm device to operate on
  74  *
  75  * Some userspace presumes that the first connected connector is the main
  76  * display, where it's supposed to display e.g. the login screen. For
  77  * laptops, this should be the main panel. Use this function to sort all
  78  * (eDP/LVDS) panels to the front of the connector list, instead of
  79  * painstakingly trying to initialize them in the right order.
  80  */
  81 void drm_helper_move_panel_connectors_to_head(struct drm_device *dev)
  82 {
  83         struct drm_connector *connector, *tmp;
  84         struct list_head panel_list;
  85
  86         INIT_LIST_HEAD(&panel_list);
  87
  88         list_for_each_entry_safe(connector, tmp,
  89                                  &dev->mode_config.connector_list, head) {
  90                 if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
  91                     connector->connector_type == DRM_MODE_CONNECTOR_eDP)
  92                         list_move_tail(&connector->head, &panel_list);
  93         }
  94
  95         list_splice(&panel_list, &dev->mode_config.connector_list);
  96 }
  97 EXPORT_SYMBOL(drm_helper_move_panel_connectors_to_head);
  98
  99 /**
 100  * drm_helper_encoder_in_use - check if a given encoder is in use
 101  * @encoder: encoder to check
 102  *
 103  * Checks whether @encoder 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 @encoder is used, false otherwise.
 109  */
 110 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
 111 {
 112         struct drm_connector *connector;
 113         struct drm_device *dev = encoder->dev;
 114
 115         /*
 116          * We can expect this mutex to be locked if we are not panicking.
 117          * Locking is currently fubar in the panic handler.
 118          */
 119         if (!oops_in_progress) {
 120                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 121                 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 122         }
 123
 124         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 125                 if (connector->encoder == encoder)
 126                         return true;
 127         return false;
 128 }
 129 EXPORT_SYMBOL(drm_helper_encoder_in_use);
 130
 131 /**
 132  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 133  * @crtc: CRTC to check
 134  *
 135  * Checks whether @crtc is with the current mode setting output configuration
 136  * in use by any connector. This doesn't mean that it is actually enabled since
 137  * the DPMS state is tracked separately.
 138  *
 139  * Returns:
 140  * True if @crtc is used, false otherwise.
 141  */
 142 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 143 {
 144         struct drm_encoder *encoder;
 145         struct drm_device *dev = crtc->dev;
 146
 147         /*
 148          * We can expect this mutex to be locked if we are not panicking.
 149          * Locking is currently fubar in the panic handler.
 150          */
 151         if (!oops_in_progress)
 152                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 153
 154         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
 155                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 156                         return true;
 157         return false;
 158 }
 159 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 160
 161 static void
 162 drm_encoder_disable(struct drm_encoder *encoder)
 163 {
 164         struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 165
 166         if (encoder->bridge)
 167                 encoder->bridge->funcs->disable(encoder->bridge);
 168
 169         if (encoder_funcs->disable)
 170                 (*encoder_funcs->disable)(encoder);
 171         else
 172                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 173
 174         if (encoder->bridge)
 175                 encoder->bridge->funcs->post_disable(encoder->bridge);
 176 }
 177
 178 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 179 {
 180         struct drm_encoder *encoder;
 181         struct drm_crtc *crtc;
 182
 183         drm_warn_on_modeset_not_all_locked(dev);
 184
 185         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 186                 if (!drm_helper_encoder_in_use(encoder)) {
 187                         drm_encoder_disable(encoder);
 188                         /* disconnect encoder from any connector */
 189                         encoder->crtc = NULL;
 190                 }
 191         }
 192
 193         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 194                 struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 195                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 196                 if (!crtc->enabled) {
 197                         if (crtc_funcs->disable)
 198                                 (*crtc_funcs->disable)(crtc);
 199                         else
 200                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 201                         crtc->primary->fb = NULL;
 202                 }
 203         }
 204 }
 205
 206 /**
 207  * drm_helper_disable_unused_functions - disable unused objects
 208  * @dev: DRM device
 209  *
 210  * This function walks through the entire mode setting configuration of @dev. It
 211  * will remove any crtc links of unused encoders and encoder links of
 212  * disconnected connectors. Then it will disable all unused encoders and crtcs
 213  * either by calling their disable callback if available or by calling their
 214  * dpms callback with DRM_MODE_DPMS_OFF.
 215  */
 216 void drm_helper_disable_unused_functions(struct drm_device *dev)
 217 {
 218         drm_modeset_lock_all(dev);
 219         __drm_helper_disable_unused_functions(dev);
 220         drm_modeset_unlock_all(dev);
 221 }
 222 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 223
 224 /*
 225  * Check the CRTC we're going to map each output to vs. its current
 226  * CRTC.  If they don't match, we have to disable the output and the CRTC
 227  * since the driver will have to re-route things.
 228  */
 229 static void
 230 drm_crtc_prepare_encoders(struct drm_device *dev)
 231 {
 232         struct drm_encoder_helper_funcs *encoder_funcs;
 233         struct drm_encoder *encoder;
 234
 235         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 236                 encoder_funcs = encoder->helper_private;
 237                 /* Disable unused encoders */
 238                 if (encoder->crtc == NULL)
 239                         drm_encoder_disable(encoder);
 240                 /* Disable encoders whose CRTC is about to change */
 241                 if (encoder_funcs->get_crtc &&
 242                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
 243                         drm_encoder_disable(encoder);
 244         }
 245 }
 246
 247 /**
 248  * drm_crtc_helper_set_mode - internal helper to set a mode
 249  * @crtc: CRTC to program
 250  * @mode: mode to use
 251  * @x: horizontal offset into the surface
 252  * @y: vertical offset into the surface
 253  * @old_fb: old framebuffer, for cleanup
 254  *
 255  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 256  * to fixup or reject the mode prior to trying to set it. This is an internal
 257  * helper that drivers could e.g. use to update properties that require the
 258  * entire output pipe to be disabled and re-enabled in a new configuration. For
 259  * example for changing whether audio is enabled on a hdmi link or for changing
 260  * panel fitter or dither attributes. It is also called by the
 261  * drm_crtc_helper_set_config() helper function to drive the mode setting
 262  * sequence.
 263  *
 264  * Returns:
 265  * True if the mode was set successfully, false otherwise.
 266  */
 267 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 268                               struct drm_display_mode *mode,
 269                               int x, int y,
 270                               struct drm_framebuffer *old_fb)
 271 {
 272         struct drm_device *dev = crtc->dev;
 273         struct drm_display_mode *adjusted_mode, saved_mode;
 274         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 275         struct drm_encoder_helper_funcs *encoder_funcs;
 276         int saved_x, saved_y;
 277         bool saved_enabled;
 278         struct drm_encoder *encoder;
 279         bool ret = true;
 280
 281         drm_warn_on_modeset_not_all_locked(dev);
 282
 283         saved_enabled = crtc->enabled;
 284         crtc->enabled = drm_helper_crtc_in_use(crtc);
 285         if (!crtc->enabled)
 286                 return true;
 287
 288         adjusted_mode = drm_mode_duplicate(dev, mode);
 289         if (!adjusted_mode) {
 290                 crtc->enabled = saved_enabled;
 291                 return false;
 292         }
 293
 294         saved_mode = crtc->mode;
 295         saved_x = crtc->x;
 296         saved_y = crtc->y;
 297
 298         /* Update crtc values up front so the driver can rely on them for mode
 299          * setting.
 300          */
 301         crtc->mode = *mode;
 302         crtc->x = x;
 303         crtc->y = y;
 304
 305         /* Pass our mode to the connectors and the CRTC to give them a chance to
 306          * adjust it according to limitations or connector properties, and also
 307          * a chance to reject the mode entirely.
 308          */
 309         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 310
 311                 if (encoder->crtc != crtc)
 312                         continue;
 313
 314                 if (encoder->bridge && encoder->bridge->funcs->mode_fixup) {
 315                         ret = encoder->bridge->funcs->mode_fixup(
 316                                         encoder->bridge, mode, adjusted_mode);
 317                         if (!ret) {
 318                                 DRM_DEBUG_KMS("Bridge fixup failed\n");
 319                                 goto done;
 320                         }
 321                 }
 322
 323                 encoder_funcs = encoder->helper_private;
 324                 if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 325                                                       adjusted_mode))) {
 326                         DRM_DEBUG_KMS("Encoder fixup failed\n");
 327                         goto done;
 328                 }
 329         }
 330
 331         if (!(ret = crtc_funcs->mode_fixup(crtc, mode, adjusted_mode))) {
 332                 DRM_DEBUG_KMS("CRTC fixup failed\n");
 333                 goto done;
 334         }
 335         DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);
 336
 337         /* Prepare the encoders and CRTCs before setting the mode. */
 338         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 339
 340                 if (encoder->crtc != crtc)
 341                         continue;
 342
 343                 if (encoder->bridge)
 344                         encoder->bridge->funcs->disable(encoder->bridge);
 345
 346                 encoder_funcs = encoder->helper_private;
 347                 /* Disable the encoders as the first thing we do. */
 348                 encoder_funcs->prepare(encoder);
 349
 350                 if (encoder->bridge)
 351                         encoder->bridge->funcs->post_disable(encoder->bridge);
 352         }
 353
 354         drm_crtc_prepare_encoders(dev);
 355
 356         crtc_funcs->prepare(crtc);
 357
 358         /* Set up the DPLL and any encoders state that needs to adjust or depend
 359          * on the DPLL.
 360          */
 361         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 362         if (!ret)
 363             goto done;
 364
 365         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 366
 367                 if (encoder->crtc != crtc)
 368                         continue;
 369
 370                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
 371                         encoder->base.id, encoder->name,
 372                         mode->base.id, mode->name);
 373                 encoder_funcs = encoder->helper_private;
 374                 encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 375
 376                 if (encoder->bridge && encoder->bridge->funcs->mode_set)
 377                         encoder->bridge->funcs->mode_set(encoder->bridge, mode,
 378                                         adjusted_mode);
 379         }
 380
 381         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 382         crtc_funcs->commit(crtc);
 383
 384         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 385
 386                 if (encoder->crtc != crtc)
 387                         continue;
 388
 389                 if (encoder->bridge)
 390                         encoder->bridge->funcs->pre_enable(encoder->bridge);
 391
 392                 encoder_funcs = encoder->helper_private;
 393                 encoder_funcs->commit(encoder);
 394
 395                 if (encoder->bridge)
 396                         encoder->bridge->funcs->enable(encoder->bridge);
 397         }
 398
 399         /* Store real post-adjustment hardware mode. */
 400         crtc->hwmode = *adjusted_mode;
 401
 402         /* Calculate and store various constants which
 403          * are later needed by vblank and swap-completion
 404          * timestamping. They are derived from true hwmode.
 405          */
 406         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 407
 408         /* FIXME: add subpixel order */
 409 done:
 410         drm_mode_destroy(dev, adjusted_mode);
 411         if (!ret) {
 412                 crtc->enabled = saved_enabled;
 413                 crtc->mode = saved_mode;
 414                 crtc->x = saved_x;
 415                 crtc->y = saved_y;
 416         }
 417
 418         return ret;
 419 }
 420 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 421
 422 static void
 423 drm_crtc_helper_disable(struct drm_crtc *crtc)
 424 {
 425         struct drm_device *dev = crtc->dev;
 426         struct drm_connector *connector;
 427         struct drm_encoder *encoder;
 428
 429         /* Decouple all encoders and their attached connectors from this crtc */
 430         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 431                 if (encoder->crtc != crtc)
 432                         continue;
 433
 434                 list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 435                         if (connector->encoder != encoder)
 436                                 continue;
 437
 438                         connector->encoder = NULL;
 439
 440                         /*
 441                          * drm_helper_disable_unused_functions() ought to be
 442                          * doing this, but since we've decoupled the encoder
 443                          * from the connector above, the required connection
 444                          * between them is henceforth no longer available.
 445                          */
 446                         connector->dpms = DRM_MODE_DPMS_OFF;
 447                 }
 448         }
 449
 450         __drm_helper_disable_unused_functions(dev);
 451 }
 452
 453 /**
 454  * drm_crtc_helper_set_config - set a new config from userspace
 455  * @set: mode set configuration
 456  *
 457  * Setup a new configuration, provided by the upper layers (either an ioctl call
 458  * from userspace or internally e.g. from the fbdev support code) in @set, and
 459  * enable it. This is the main helper functions for drivers that implement
 460  * kernel mode setting with the crtc helper functions and the assorted
 461  * ->prepare(), ->modeset() and ->commit() helper callbacks.
 462  *
 463  * Returns:
 464  * Returns 0 on success, negative errno numbers on failure.
 465  */
 466 int drm_crtc_helper_set_config(struct drm_mode_set *set)
 467 {
 468         struct drm_device *dev;
 469         struct drm_crtc *new_crtc;
 470         struct drm_encoder *save_encoders, *new_encoder, *encoder;
 471         bool mode_changed = false; /* if true do a full mode set */
 472         bool fb_changed = false; /* if true and !mode_changed just do a flip */
 473         struct drm_connector *save_connectors, *connector;
 474         int count = 0, ro, fail = 0;
 475         struct drm_crtc_helper_funcs *crtc_funcs;
 476         struct drm_mode_set save_set;
 477         int ret;
 478         int i;
 479
 480         DRM_DEBUG_KMS("\n");
 481
 482         BUG_ON(!set);
 483         BUG_ON(!set->crtc);
 484         BUG_ON(!set->crtc->helper_private);
 485
 486         /* Enforce sane interface api - has been abused by the fb helper. */
 487         BUG_ON(!set->mode && set->fb);
 488         BUG_ON(set->fb && set->num_connectors == 0);
 489
 490         crtc_funcs = set->crtc->helper_private;
 491
 492         if (!set->mode)
 493                 set->fb = NULL;
 494
 495         if (set->fb) {
 496                 DRM_DEBUG_KMS("[CRTC:%d] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 497                                 set->crtc->base.id, set->fb->base.id,
 498                                 (int)set->num_connectors, set->x, set->y);
 499         } else {
 500                 DRM_DEBUG_KMS("[CRTC:%d] [NOFB]\n", set->crtc->base.id);
 501                 drm_crtc_helper_disable(set->crtc);
 502                 return 0;
 503         }
 504
 505         dev = set->crtc->dev;
 506
 507         drm_warn_on_modeset_not_all_locked(dev);
 508
 509         /*
 510          * Allocate space for the backup of all (non-pointer) encoder and
 511          * connector data.
 512          */
 513         save_encoders = kzalloc(dev->mode_config.num_encoder *
 514                                 sizeof(struct drm_encoder), GFP_KERNEL);
 515         if (!save_encoders)
 516                 return -ENOMEM;
 517
 518         save_connectors = kzalloc(dev->mode_config.num_connector *
 519                                 sizeof(struct drm_connector), GFP_KERNEL);
 520         if (!save_connectors) {
 521                 kfree(save_encoders);
 522                 return -ENOMEM;
 523         }
 524
 525         /*
 526          * Copy data. Note that driver private data is not affected.
 527          * Should anything bad happen only the expected state is
 528          * restored, not the drivers personal bookkeeping.
 529          */
 530         count = 0;
 531         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 532                 save_encoders[count++] = *encoder;
 533         }
 534
 535         count = 0;
 536         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 537                 save_connectors[count++] = *connector;
 538         }
 539
 540         save_set.crtc = set->crtc;
 541         save_set.mode = &set->crtc->mode;
 542         save_set.x = set->crtc->x;
 543         save_set.y = set->crtc->y;
 544         save_set.fb = set->crtc->primary->fb;
 545
 546         /* We should be able to check here if the fb has the same properties
 547          * and then just flip_or_move it */
 548         if (set->crtc->primary->fb != set->fb) {
 549                 /* If we have no fb then treat it as a full mode set */
 550                 if (set->crtc->primary->fb == NULL) {
 551                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 552                         mode_changed = true;
 553                 } else if (set->fb == NULL) {
 554                         mode_changed = true;
 555                 } else if (set->fb->pixel_format !=
 556                            set->crtc->primary->fb->pixel_format) {
 557                         mode_changed = true;
 558                 } else
 559                         fb_changed = true;
 560         }
 561
 562         if (set->x != set->crtc->x || set->y != set->crtc->y)
 563                 fb_changed = true;
 564
 565         if (set->mode && !drm_mode_equal(set->mode, &set->crtc->mode)) {
 566                 DRM_DEBUG_KMS("modes are different, full mode set\n");
 567                 drm_mode_debug_printmodeline(&set->crtc->mode);
 568                 drm_mode_debug_printmodeline(set->mode);
 569                 mode_changed = true;
 570         }
 571
 572         /* a) traverse passed in connector list and get encoders for them */
 573         count = 0;
 574         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 575                 struct drm_connector_helper_funcs *connector_funcs =
 576                         connector->helper_private;
 577                 new_encoder = connector->encoder;
 578                 for (ro = 0; ro < set->num_connectors; ro++) {
 579                         if (set->connectors[ro] == connector) {
 580                                 new_encoder = connector_funcs->best_encoder(connector);
 581                                 /* if we can't get an encoder for a connector
 582                                    we are setting now - then fail */
 583                                 if (new_encoder == NULL)
 584                                         /* don't break so fail path works correct */
 585                                         fail = 1;
 586
 587                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
 588                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 589                                         mode_changed = true;
 590                                 }
 591
 592                                 break;
 593                         }
 594                 }
 595
 596                 if (new_encoder != connector->encoder) {
 597                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 598                         mode_changed = true;
 599                         /* If the encoder is reused for another connector, then
 600                          * the appropriate crtc will be set later.
 601                          */
 602                         if (connector->encoder)
 603                                 connector->encoder->crtc = NULL;
 604                         connector->encoder = new_encoder;
 605                 }
 606         }
 607
 608         if (fail) {
 609                 ret = -EINVAL;
 610                 goto fail;
 611         }
 612
 613         count = 0;
 614         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 615                 if (!connector->encoder)
 616                         continue;
 617
 618                 if (connector->encoder->crtc == set->crtc)
 619                         new_crtc = NULL;
 620                 else
 621                         new_crtc = connector->encoder->crtc;
 622
 623                 for (ro = 0; ro < set->num_connectors; ro++) {
 624                         if (set->connectors[ro] == connector)
 625                                 new_crtc = set->crtc;
 626                 }
 627
 628                 /* Make sure the new CRTC will work with the encoder */
 629                 if (new_crtc &&
 630                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 631                         ret = -EINVAL;
 632                         goto fail;
 633                 }
 634                 if (new_crtc != connector->encoder->crtc) {
 635                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 636                         mode_changed = true;
 637                         connector->encoder->crtc = new_crtc;
 638                 }
 639                 if (new_crtc) {
 640                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d]\n",
 641                                 connector->base.id, connector->name,
 642                                 new_crtc->base.id);
 643                 } else {
 644                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 645                                 connector->base.id, connector->name);
 646                 }
 647         }
 648
 649         /* mode_set_base is not a required function */
 650         if (fb_changed && !crtc_funcs->mode_set_base)
 651                 mode_changed = true;
 652
 653         if (mode_changed) {
 654                 if (drm_helper_crtc_in_use(set->crtc)) {
 655                         DRM_DEBUG_KMS("attempting to set mode from"
 656                                         " userspace\n");
 657                         drm_mode_debug_printmodeline(set->mode);
 658                         set->crtc->primary->fb = set->fb;
 659                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 660                                                       set->x, set->y,
 661                                                       save_set.fb)) {
 662                                 DRM_ERROR("failed to set mode on [CRTC:%d]\n",
 663                                           set->crtc->base.id);
 664                                 set->crtc->primary->fb = save_set.fb;
 665                                 ret = -EINVAL;
 666                                 goto fail;
 667                         }
 668                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 669                         for (i = 0; i < set->num_connectors; i++) {
 670                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 671                                               set->connectors[i]->name);
 672                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 673                         }
 674                 }
 675                 __drm_helper_disable_unused_functions(dev);
 676         } else if (fb_changed) {
 677                 set->crtc->x = set->x;
 678                 set->crtc->y = set->y;
 679                 set->crtc->primary->fb = set->fb;
 680                 ret = crtc_funcs->mode_set_base(set->crtc,
 681                                                 set->x, set->y, save_set.fb);
 682                 if (ret != 0) {
 683                         set->crtc->x = save_set.x;
 684                         set->crtc->y = save_set.y;
 685                         set->crtc->primary->fb = save_set.fb;
 686                         goto fail;
 687                 }
 688         }
 689
 690         kfree(save_connectors);
 691         kfree(save_encoders);
 692         return 0;
 693
 694 fail:
 695         /* Restore all previous data. */
 696         count = 0;
 697         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 698                 *encoder = save_encoders[count++];
 699         }
 700
 701         count = 0;
 702         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 703                 *connector = save_connectors[count++];
 704         }
 705
 706         /* Try to restore the config */
 707         if (mode_changed &&
 708             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 709                                       save_set.y, save_set.fb))
 710                 DRM_ERROR("failed to restore config after modeset failure\n");
 711
 712         kfree(save_connectors);
 713         kfree(save_encoders);
 714         return ret;
 715 }
 716 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 717
 718 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 719 {
 720         int dpms = DRM_MODE_DPMS_OFF;
 721         struct drm_connector *connector;
 722         struct drm_device *dev = encoder->dev;
 723
 724         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 725                 if (connector->encoder == encoder)
 726                         if (connector->dpms < dpms)
 727                                 dpms = connector->dpms;
 728         return dpms;
 729 }
 730
 731 /* Helper which handles bridge ordering around encoder dpms */
 732 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 733 {
 734         struct drm_bridge *bridge = encoder->bridge;
 735         struct drm_encoder_helper_funcs *encoder_funcs;
 736
 737         if (bridge) {
 738                 if (mode == DRM_MODE_DPMS_ON)
 739                         bridge->funcs->pre_enable(bridge);
 740                 else
 741                         bridge->funcs->disable(bridge);
 742         }
 743
 744         encoder_funcs = encoder->helper_private;
 745         if (encoder_funcs->dpms)
 746                 encoder_funcs->dpms(encoder, mode);
 747
 748         if (bridge) {
 749                 if (mode == DRM_MODE_DPMS_ON)
 750                         bridge->funcs->enable(bridge);
 751                 else
 752                         bridge->funcs->post_disable(bridge);
 753         }
 754 }
 755
 756 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 757 {
 758         int dpms = DRM_MODE_DPMS_OFF;
 759         struct drm_connector *connector;
 760         struct drm_device *dev = crtc->dev;
 761
 762         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 763                 if (connector->encoder && connector->encoder->crtc == crtc)
 764                         if (connector->dpms < dpms)
 765                                 dpms = connector->dpms;
 766         return dpms;
 767 }
 768
 769 /**
 770  * drm_helper_connector_dpms() - connector dpms helper implementation
 771  * @connector: affected connector
 772  * @mode: DPMS mode
 773  *
 774  * This is the main helper function provided by the crtc helper framework for
 775  * implementing the DPMS connector attribute. It computes the new desired DPMS
 776  * state for all encoders and crtcs in the output mesh and calls the ->dpms()
 777  * callback provided by the driver appropriately.
 778  */
 779 void drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 780 {
 781         struct drm_encoder *encoder = connector->encoder;
 782         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 783         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 784
 785         if (mode == connector->dpms)
 786                 return;
 787
 788         old_dpms = connector->dpms;
 789         connector->dpms = mode;
 790
 791         if (encoder)
 792                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 793
 794         /* from off to on, do crtc then encoder */
 795         if (mode < old_dpms) {
 796                 if (crtc) {
 797                         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 798                         if (crtc_funcs->dpms)
 799                                 (*crtc_funcs->dpms) (crtc,
 800                                                      drm_helper_choose_crtc_dpms(crtc));
 801                 }
 802                 if (encoder)
 803                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 804         }
 805
 806         /* from on to off, do encoder then crtc */
 807         if (mode > old_dpms) {
 808                 if (encoder)
 809                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 810                 if (crtc) {
 811                         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 812                         if (crtc_funcs->dpms)
 813                                 (*crtc_funcs->dpms) (crtc,
 814                                                      drm_helper_choose_crtc_dpms(crtc));
 815                 }
 816         }
 817
 818         return;
 819 }
 820 EXPORT_SYMBOL(drm_helper_connector_dpms);
 821
 822 /**
 823  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
 824  * @fb: drm_framebuffer object to fill out
 825  * @mode_cmd: metadata from the userspace fb creation request
 826  *
 827  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
 828  * metadata fields.
 829  */
 830 void drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
 831                                     struct drm_mode_fb_cmd2 *mode_cmd)
 832 {
 833         int i;
 834
 835         fb->width = mode_cmd->width;
 836         fb->height = mode_cmd->height;
 837         for (i = 0; i < 4; i++) {
 838                 fb->pitches[i] = mode_cmd->pitches[i];
 839                 fb->offsets[i] = mode_cmd->offsets[i];
 840         }
 841         drm_fb_get_bpp_depth(mode_cmd->pixel_format, &fb->depth,
 842                                     &fb->bits_per_pixel);
 843         fb->pixel_format = mode_cmd->pixel_format;
 844         fb->flags = mode_cmd->flags;
 845 }
 846 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
 847
 848 /**
 849  * drm_helper_resume_force_mode - force-restore mode setting configuration
 850  * @dev: drm_device which should be restored
 851  *
 852  * Drivers which use the mode setting helpers can use this function to
 853  * force-restore the mode setting configuration e.g. on resume or when something
 854  * else might have trampled over the hw state (like some overzealous old BIOSen
 855  * tended to do).
 856  *
 857  * This helper doesn't provide a error return value since restoring the old
 858  * config should never fail due to resource allocation issues since the driver
 859  * has successfully set the restored configuration already. Hence this should
 860  * boil down to the equivalent of a few dpms on calls, which also don't provide
 861  * an error code.
 862  *
 863  * Drivers where simply restoring an old configuration again might fail (e.g.
 864  * due to slight differences in allocating shared resources when the
 865  * configuration is restored in a different order than when userspace set it up)
 866  * need to use their own restore logic.
 867  */
 868 void drm_helper_resume_force_mode(struct drm_device *dev)
 869 {
 870         struct drm_crtc *crtc;
 871         struct drm_encoder *encoder;
 872         struct drm_crtc_helper_funcs *crtc_funcs;
 873         int encoder_dpms;
 874         bool ret;
 875
 876         drm_modeset_lock_all(dev);
 877         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 878
 879                 if (!crtc->enabled)
 880                         continue;
 881
 882                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 883                                                crtc->x, crtc->y, crtc->primary->fb);
 884
 885                 /* Restoring the old config should never fail! */
 886                 if (ret == false)
 887                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 888
 889                 /* Turn off outputs that were already powered off */
 890                 if (drm_helper_choose_crtc_dpms(crtc)) {
 891                         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 892
 893                                 if(encoder->crtc != crtc)
 894                                         continue;
 895
 896                                 encoder_dpms = drm_helper_choose_encoder_dpms(
 897                                                         encoder);
 898
 899                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
 900                         }
 901
 902                         crtc_funcs = crtc->helper_private;
 903                         if (crtc_funcs->dpms)
 904                                 (*crtc_funcs->dpms) (crtc,
 905                                                      drm_helper_choose_crtc_dpms(crtc));
 906                 }
 907         }
 908
 909         /* disable the unused connectors while restoring the modesetting */
 910         __drm_helper_disable_unused_functions(dev);
 911         drm_modeset_unlock_all(dev);
 912 }
 913 EXPORT_SYMBOL(drm_helper_resume_force_mode);
 914
 915 /**
 916  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
 917  * @crtc: DRM CRTC
 918  * @mode: DRM display mode which userspace requested
 919  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
 920  * @x: x offset of the CRTC scanout area on the underlying framebuffer
 921  * @y: y offset of the CRTC scanout area on the underlying framebuffer
 922  * @old_fb: previous framebuffer
 923  *
 924  * This function implements a callback useable as the ->mode_set callback
 925  * required by the crtc helpers. Besides the atomic plane helper functions for
 926  * the primary plane the driver must also provide the ->mode_set_nofb callback
 927  * to set up the crtc.
 928  *
 929  * This is a transitional helper useful for converting drivers to the atomic
 930  * interfaces.
 931  */
 932 int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
 933                              struct drm_display_mode *adjusted_mode, int x, int y,
 934                              struct drm_framebuffer *old_fb)
 935 {
 936         struct drm_crtc_state *crtc_state;
 937         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 938         int ret;
 939
 940         if (crtc->funcs->atomic_duplicate_state)
 941                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
 942         else if (crtc->state)
 943                 crtc_state = kmemdup(crtc->state, sizeof(*crtc_state),
 944                                      GFP_KERNEL);
 945         else
 946                 crtc_state = kzalloc(sizeof(*crtc_state), GFP_KERNEL);
 947         if (!crtc_state)
 948                 return -ENOMEM;
 949
 950         crtc_state->enable = true;
 951         crtc_state->planes_changed = true;
 952         crtc_state->mode_changed = true;
 953         drm_mode_copy(&crtc_state->mode, mode);
 954         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
 955
 956         if (crtc_funcs->atomic_check) {
 957                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
 958                 if (ret) {
 959                         kfree(crtc_state);
 960
 961                         return ret;
 962                 }
 963         }
 964
 965         swap(crtc->state, crtc_state);
 966
 967         crtc_funcs->mode_set_nofb(crtc);
 968
 969         if (crtc_state) {
 970                 if (crtc->funcs->atomic_destroy_state)
 971                         crtc->funcs->atomic_destroy_state(crtc, crtc_state);
 972                 else
 973                         kfree(crtc_state);
 974         }
 975
 976         return drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
 977 }
 978 EXPORT_SYMBOL(drm_helper_crtc_mode_set);
 979
 980 /**
 981  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
 982  * @crtc: DRM CRTC
 983  * @x: x offset of the CRTC scanout area on the underlying framebuffer
 984  * @y: y offset of the CRTC scanout area on the underlying framebuffer
 985  * @old_fb: previous framebuffer
 986  *
 987  * This function implements a callback useable as the ->mode_set_base used
 988  * required by the crtc helpers. The driver must provide the atomic plane helper
 989  * functions for the primary plane.
 990  *
 991  * This is a transitional helper useful for converting drivers to the atomic
 992  * interfaces.
 993  */
 994 int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
 995                                   struct drm_framebuffer *old_fb)
 996 {
 997         struct drm_plane_state *plane_state;
 998         struct drm_plane *plane = crtc->primary;
 999
1000         if (plane->funcs->atomic_duplicate_state)
1001                 plane_state = plane->funcs->atomic_duplicate_state(plane);
1002         else if (plane->state)
1003                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
1004         else
1005                 plane_state = kzalloc(sizeof(*plane_state), GFP_KERNEL);
1006         if (!plane_state)
1007                 return -ENOMEM;
1008
1009         plane_state->crtc = crtc;
1010         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
1011         plane_state->crtc_x = 0;
1012         plane_state->crtc_y = 0;
1013         plane_state->crtc_h = crtc->mode.vdisplay;
1014         plane_state->crtc_w = crtc->mode.hdisplay;
1015         plane_state->src_x = x << 16;
1016         plane_state->src_y = y << 16;
1017         plane_state->src_h = crtc->mode.vdisplay << 16;
1018         plane_state->src_w = crtc->mode.hdisplay << 16;
1019
1020         return drm_plane_helper_commit(plane, plane_state, old_fb);
1021 }
1022 EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);