drivers/gpu/drm/drm_crtc_helper.c

   1 /*
   2  * Copyright (c) 2006-2008 Intel Corporation
   3  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
   4  *
   5  * DRM core CRTC related functions
   6  *
   7  * Permission to use, copy, modify, distribute, and sell this software and its
   8  * documentation for any purpose is hereby granted without fee, provided that
   9  * the above copyright notice appear in all copies and that both that copyright
  10  * notice and this permission notice appear in supporting documentation, and
  11  * that the name of the copyright holders not be used in advertising or
  12  * publicity pertaining to distribution of the software without specific,
  13  * written prior permission.  The copyright holders make no representations
  14  * about the suitability of this software for any purpose.  It is provided "as
  15  * is" without express or implied warranty.
  16  *
  17  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  18  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  19  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  20  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  21  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  22  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  23  * OF THIS SOFTWARE.
  24  *
  25  * Authors:
  26  *      Keith Packard
  27  *      Eric Anholt <eric@anholt.net>
  28  *      Dave Airlie <airlied@linux.ie>
  29  *      Jesse Barnes <jesse.barnes@intel.com>
  30  */
  31
  32 #include <linux/kernel.h>
  33 #include <linux/export.h>
  34 #include <linux/moduleparam.h>
  35
  36 #include <drm/drmP.h>
  37 #include <drm/drm_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  * Note that this helper library doesn't track the current power state of CRTCs
  55  * and encoders. It can call callbacks like ->dpms() even though the hardware is
  56  * already in the desired state. This deficiency has been fixed in the atomic
  57  * helpers.
  58  *
  59  * The driver callbacks are mostly compatible with the atomic modeset helpers,
  60  * except for the handling of the primary plane: Atomic helpers require that the
  61  * primary plane is implemented as a real standalone plane and not directly tied
  62  * to the CRTC state. For easier transition this library provides functions to
  63  * implement the old semantics required by the CRTC helpers using the new plane
  64  * and atomic helper callbacks.
  65  *
  66  * Drivers are strongly urged to convert to the atomic helpers (by way of first
  67  * converting to the plane helpers). New drivers must not use these functions
  68  * but need to implement the atomic interface instead, potentially using the
  69  * atomic helpers for that.
  70  *
  71  * These legacy modeset helpers use the same function table structures as
  72  * all other modesetting helpers. See the documentation for struct
  73  * &drm_crtc_helper_funcs, struct &drm_encoder_helper_funcs and struct
  74  * &drm_connector_helper_funcs.
  75  */
  76
  77 /**
  78  * drm_helper_move_panel_connectors_to_head() - move panels to the front in the
  79  *                                              connector list
  80  * @dev: drm device to operate on
  81  *
  82  * Some userspace presumes that the first connected connector is the main
  83  * display, where it's supposed to display e.g. the login screen. For
  84  * laptops, this should be the main panel. Use this function to sort all
  85  * (eDP/LVDS) panels to the front of the connector list, instead of
  86  * painstakingly trying to initialize them in the right order.
  87  */
  88 void drm_helper_move_panel_connectors_to_head(struct drm_device *dev)
  89 {
  90         struct drm_connector *connector, *tmp;
  91         struct list_head panel_list;
  92
  93         INIT_LIST_HEAD(&panel_list);
  94
  95         list_for_each_entry_safe(connector, tmp,
  96                                  &dev->mode_config.connector_list, head) {
  97                 if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
  98                     connector->connector_type == DRM_MODE_CONNECTOR_eDP)
  99                         list_move_tail(&connector->head, &panel_list);
 100         }
 101
 102         list_splice(&panel_list, &dev->mode_config.connector_list);
 103 }
 104 EXPORT_SYMBOL(drm_helper_move_panel_connectors_to_head);
 105
 106 /**
 107  * drm_helper_encoder_in_use - check if a given encoder is in use
 108  * @encoder: encoder to check
 109  *
 110  * Checks whether @encoder is with the current mode setting output configuration
 111  * in use by any connector. This doesn't mean that it is actually enabled since
 112  * the DPMS state is tracked separately.
 113  *
 114  * Returns:
 115  * True if @encoder is used, false otherwise.
 116  */
 117 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
 118 {
 119         struct drm_connector *connector;
 120         struct drm_device *dev = encoder->dev;
 121
 122         /*
 123          * We can expect this mutex to be locked if we are not panicking.
 124          * Locking is currently fubar in the panic handler.
 125          */
 126         if (!oops_in_progress) {
 127                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 128                 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 129         }
 130
 131         drm_for_each_connector(connector, dev)
 132                 if (connector->encoder == encoder)
 133                         return true;
 134         return false;
 135 }
 136 EXPORT_SYMBOL(drm_helper_encoder_in_use);
 137
 138 /**
 139  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 140  * @crtc: CRTC to check
 141  *
 142  * Checks whether @crtc is with the current mode setting output configuration
 143  * in use by any connector. This doesn't mean that it is actually enabled since
 144  * the DPMS state is tracked separately.
 145  *
 146  * Returns:
 147  * True if @crtc is used, false otherwise.
 148  */
 149 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 150 {
 151         struct drm_encoder *encoder;
 152         struct drm_device *dev = crtc->dev;
 153
 154         /*
 155          * We can expect this mutex to be locked if we are not panicking.
 156          * Locking is currently fubar in the panic handler.
 157          */
 158         if (!oops_in_progress)
 159                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 160
 161         drm_for_each_encoder(encoder, dev)
 162                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 163                         return true;
 164         return false;
 165 }
 166 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 167
 168 static void
 169 drm_encoder_disable(struct drm_encoder *encoder)
 170 {
 171         const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 172
 173         if (!encoder_funcs)
 174                 return;
 175
 176         drm_bridge_disable(encoder->bridge);
 177
 178         if (encoder_funcs->disable)
 179                 (*encoder_funcs->disable)(encoder);
 180         else if (encoder_funcs->dpms)
 181                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 182
 183         drm_bridge_post_disable(encoder->bridge);
 184 }
 185
 186 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 187 {
 188         struct drm_encoder *encoder;
 189         struct drm_crtc *crtc;
 190
 191         drm_warn_on_modeset_not_all_locked(dev);
 192
 193         drm_for_each_encoder(encoder, dev) {
 194                 if (!drm_helper_encoder_in_use(encoder)) {
 195                         drm_encoder_disable(encoder);
 196                         /* disconnect encoder from any connector */
 197                         encoder->crtc = NULL;
 198                 }
 199         }
 200
 201         drm_for_each_crtc(crtc, dev) {
 202                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 203                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 204                 if (!crtc->enabled) {
 205                         if (crtc_funcs->disable)
 206                                 (*crtc_funcs->disable)(crtc);
 207                         else
 208                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 209                         crtc->primary->fb = NULL;
 210                 }
 211         }
 212 }
 213
 214 /**
 215  * drm_helper_disable_unused_functions - disable unused objects
 216  * @dev: DRM device
 217  *
 218  * This function walks through the entire mode setting configuration of @dev. It
 219  * will remove any CRTC links of unused encoders and encoder links of
 220  * disconnected connectors. Then it will disable all unused encoders and CRTCs
 221  * either by calling their disable callback if available or by calling their
 222  * dpms callback with DRM_MODE_DPMS_OFF.
 223  *
 224  * NOTE:
 225  *
 226  * This function is part of the legacy modeset helper library and will cause
 227  * major confusion with atomic drivers. This is because atomic helpers guarantee
 228  * to never call ->disable() hooks on a disabled function, or ->enable() hooks
 229  * on an enabled functions. drm_helper_disable_unused_functions() on the other
 230  * hand throws such guarantees into the wind and calls disable hooks
 231  * unconditionally on unused functions.
 232  */
 233 void drm_helper_disable_unused_functions(struct drm_device *dev)
 234 {
 235         drm_modeset_lock_all(dev);
 236         __drm_helper_disable_unused_functions(dev);
 237         drm_modeset_unlock_all(dev);
 238 }
 239 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 240
 241 /*
 242  * Check the CRTC we're going to map each output to vs. its current
 243  * CRTC.  If they don't match, we have to disable the output and the CRTC
 244  * since the driver will have to re-route things.
 245  */
 246 static void
 247 drm_crtc_prepare_encoders(struct drm_device *dev)
 248 {
 249         const struct drm_encoder_helper_funcs *encoder_funcs;
 250         struct drm_encoder *encoder;
 251
 252         drm_for_each_encoder(encoder, dev) {
 253                 encoder_funcs = encoder->helper_private;
 254                 if (!encoder_funcs)
 255                         continue;
 256
 257                 /* Disable unused encoders */
 258                 if (encoder->crtc == NULL)
 259                         drm_encoder_disable(encoder);
 260                 /* Disable encoders whose CRTC is about to change */
 261                 if (encoder_funcs->get_crtc &&
 262                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
 263                         drm_encoder_disable(encoder);
 264         }
 265 }
 266
 267 /**
 268  * drm_crtc_helper_set_mode - internal helper to set a mode
 269  * @crtc: CRTC to program
 270  * @mode: mode to use
 271  * @x: horizontal offset into the surface
 272  * @y: vertical offset into the surface
 273  * @old_fb: old framebuffer, for cleanup
 274  *
 275  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 276  * to fixup or reject the mode prior to trying to set it. This is an internal
 277  * helper that drivers could e.g. use to update properties that require the
 278  * entire output pipe to be disabled and re-enabled in a new configuration. For
 279  * example for changing whether audio is enabled on a hdmi link or for changing
 280  * panel fitter or dither attributes. It is also called by the
 281  * drm_crtc_helper_set_config() helper function to drive the mode setting
 282  * sequence.
 283  *
 284  * Returns:
 285  * True if the mode was set successfully, false otherwise.
 286  */
 287 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 288                               struct drm_display_mode *mode,
 289                               int x, int y,
 290                               struct drm_framebuffer *old_fb)
 291 {
 292         struct drm_device *dev = crtc->dev;
 293         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
 294         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 295         const struct drm_encoder_helper_funcs *encoder_funcs;
 296         int saved_x, saved_y;
 297         bool saved_enabled;
 298         struct drm_encoder *encoder;
 299         bool ret = true;
 300
 301         drm_warn_on_modeset_not_all_locked(dev);
 302
 303         saved_enabled = crtc->enabled;
 304         crtc->enabled = drm_helper_crtc_in_use(crtc);
 305         if (!crtc->enabled)
 306                 return true;
 307
 308         adjusted_mode = drm_mode_duplicate(dev, mode);
 309         if (!adjusted_mode) {
 310                 crtc->enabled = saved_enabled;
 311                 return false;
 312         }
 313
 314         saved_mode = crtc->mode;
 315         saved_hwmode = crtc->hwmode;
 316         saved_x = crtc->x;
 317         saved_y = crtc->y;
 318
 319         /* Update crtc values up front so the driver can rely on them for mode
 320          * setting.
 321          */
 322         crtc->mode = *mode;
 323         crtc->x = x;
 324         crtc->y = y;
 325
 326         /* Pass our mode to the connectors and the CRTC to give them a chance to
 327          * adjust it according to limitations or connector properties, and also
 328          * a chance to reject the mode entirely.
 329          */
 330         drm_for_each_encoder(encoder, dev) {
 331
 332                 if (encoder->crtc != crtc)
 333                         continue;
 334
 335                 encoder_funcs = encoder->helper_private;
 336                 if (!encoder_funcs)
 337                         continue;
 338
 339                 ret = drm_bridge_mode_fixup(encoder->bridge,
 340                         mode, adjusted_mode);
 341                 if (!ret) {
 342                         DRM_DEBUG_KMS("Bridge fixup failed\n");
 343                         goto done;
 344                 }
 345
 346                 encoder_funcs = encoder->helper_private;
 347                 if (encoder_funcs->mode_fixup) {
 348                         if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 349                                                               adjusted_mode))) {
 350                                 DRM_DEBUG_KMS("Encoder fixup failed\n");
 351                                 goto done;
 352                         }
 353                 }
 354         }
 355
 356         if (crtc_funcs->mode_fixup) {
 357                 if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
 358                                                 adjusted_mode))) {
 359                         DRM_DEBUG_KMS("CRTC fixup failed\n");
 360                         goto done;
 361                 }
 362         }
 363         DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
 364
 365         crtc->hwmode = *adjusted_mode;
 366
 367         /* Prepare the encoders and CRTCs before setting the mode. */
 368         drm_for_each_encoder(encoder, dev) {
 369
 370                 if (encoder->crtc != crtc)
 371                         continue;
 372
 373                 encoder_funcs = encoder->helper_private;
 374                 if (!encoder_funcs)
 375                         continue;
 376
 377                 drm_bridge_disable(encoder->bridge);
 378
 379                 /* Disable the encoders as the first thing we do. */
 380                 if (encoder_funcs->prepare)
 381                         encoder_funcs->prepare(encoder);
 382
 383                 drm_bridge_post_disable(encoder->bridge);
 384         }
 385
 386         drm_crtc_prepare_encoders(dev);
 387
 388         crtc_funcs->prepare(crtc);
 389
 390         /* Set up the DPLL and any encoders state that needs to adjust or depend
 391          * on the DPLL.
 392          */
 393         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 394         if (!ret)
 395             goto done;
 396
 397         drm_for_each_encoder(encoder, dev) {
 398
 399                 if (encoder->crtc != crtc)
 400                         continue;
 401
 402                 encoder_funcs = encoder->helper_private;
 403                 if (!encoder_funcs)
 404                         continue;
 405
 406                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
 407                         encoder->base.id, encoder->name,
 408                         mode->base.id, mode->name);
 409                 if (encoder_funcs->mode_set)
 410                         encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 411
 412                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
 413         }
 414
 415         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 416         crtc_funcs->commit(crtc);
 417
 418         drm_for_each_encoder(encoder, dev) {
 419
 420                 if (encoder->crtc != crtc)
 421                         continue;
 422
 423                 encoder_funcs = encoder->helper_private;
 424                 if (!encoder_funcs)
 425                         continue;
 426
 427                 drm_bridge_pre_enable(encoder->bridge);
 428
 429                 if (encoder_funcs->commit)
 430                         encoder_funcs->commit(encoder);
 431
 432                 drm_bridge_enable(encoder->bridge);
 433         }
 434
 435         /* Calculate and store various constants which
 436          * are later needed by vblank and swap-completion
 437          * timestamping. They are derived from true hwmode.
 438          */
 439         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 440
 441         /* FIXME: add subpixel order */
 442 done:
 443         drm_mode_destroy(dev, adjusted_mode);
 444         if (!ret) {
 445                 crtc->enabled = saved_enabled;
 446                 crtc->mode = saved_mode;
 447                 crtc->hwmode = saved_hwmode;
 448                 crtc->x = saved_x;
 449                 crtc->y = saved_y;
 450         }
 451
 452         return ret;
 453 }
 454 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 455
 456 static void
 457 drm_crtc_helper_disable(struct drm_crtc *crtc)
 458 {
 459         struct drm_device *dev = crtc->dev;
 460         struct drm_connector *connector;
 461         struct drm_encoder *encoder;
 462
 463         /* Decouple all encoders and their attached connectors from this crtc */
 464         drm_for_each_encoder(encoder, dev) {
 465                 if (encoder->crtc != crtc)
 466                         continue;
 467
 468                 drm_for_each_connector(connector, dev) {
 469                         if (connector->encoder != encoder)
 470                                 continue;
 471
 472                         connector->encoder = NULL;
 473
 474                         /*
 475                          * drm_helper_disable_unused_functions() ought to be
 476                          * doing this, but since we've decoupled the encoder
 477                          * from the connector above, the required connection
 478                          * between them is henceforth no longer available.
 479                          */
 480                         connector->dpms = DRM_MODE_DPMS_OFF;
 481
 482                         /* we keep a reference while the encoder is bound */
 483                         drm_connector_unreference(connector);
 484                 }
 485         }
 486
 487         __drm_helper_disable_unused_functions(dev);
 488 }
 489
 490 /**
 491  * drm_crtc_helper_set_config - set a new config from userspace
 492  * @set: mode set configuration
 493  *
 494  * The drm_crtc_helper_set_config() helper function implements the set_config
 495  * callback of struct &drm_crtc_funcs for drivers using the legacy CRTC helpers.
 496  *
 497  * It first tries to locate the best encoder for each connector by calling the
 498  * connector ->best_encoder() (struct &drm_connector_helper_funcs) helper
 499  * operation.
 500  *
 501  * After locating the appropriate encoders, the helper function will call the
 502  * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
 503  * or reject it completely in which case an error will be returned to the
 504  * application. If the new configuration after mode adjustment is identical to
 505  * the current configuration the helper function will return without performing
 506  * any other operation.
 507  *
 508  * If the adjusted mode is identical to the current mode but changes to the
 509  * frame buffer need to be applied, the drm_crtc_helper_set_config() function
 510  * will call the CRTC ->mode_set_base() (struct &drm_crtc_helper_funcs) helper
 511  * operation.
 512  *
 513  * If the adjusted mode differs from the current mode, or if the
 514  * ->mode_set_base() helper operation is not provided, the helper function
 515  * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
 516  * and ->commit() CRTC and encoder helper operations, in that order.
 517  * Alternatively it can also use the dpms and disable helper operations. For
 518  * details see struct &drm_crtc_helper_funcs and struct
 519  * &drm_encoder_helper_funcs.
 520  *
 521  * This function is deprecated.  New drivers must implement atomic modeset
 522  * support, for which this function is unsuitable. Instead drivers should use
 523  * drm_atomic_helper_set_config().
 524  *
 525  * Returns:
 526  * Returns 0 on success, negative errno numbers on failure.
 527  */
 528 int drm_crtc_helper_set_config(struct drm_mode_set *set)
 529 {
 530         struct drm_device *dev;
 531         struct drm_crtc *new_crtc;
 532         struct drm_encoder *save_encoders, *new_encoder, *encoder;
 533         bool mode_changed = false; /* if true do a full mode set */
 534         bool fb_changed = false; /* if true and !mode_changed just do a flip */
 535         struct drm_connector *save_connectors, *connector;
 536         int count = 0, ro, fail = 0;
 537         const struct drm_crtc_helper_funcs *crtc_funcs;
 538         struct drm_mode_set save_set;
 539         int ret;
 540         int i;
 541
 542         DRM_DEBUG_KMS("\n");
 543
 544         BUG_ON(!set);
 545         BUG_ON(!set->crtc);
 546         BUG_ON(!set->crtc->helper_private);
 547
 548         /* Enforce sane interface api - has been abused by the fb helper. */
 549         BUG_ON(!set->mode && set->fb);
 550         BUG_ON(set->fb && set->num_connectors == 0);
 551
 552         crtc_funcs = set->crtc->helper_private;
 553
 554         if (!set->mode)
 555                 set->fb = NULL;
 556
 557         if (set->fb) {
 558                 DRM_DEBUG_KMS("[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 559                               set->crtc->base.id, set->crtc->name,
 560                               set->fb->base.id,
 561                               (int)set->num_connectors, set->x, set->y);
 562         } else {
 563                 DRM_DEBUG_KMS("[CRTC:%d:%s] [NOFB]\n",
 564                               set->crtc->base.id, set->crtc->name);
 565                 drm_crtc_helper_disable(set->crtc);
 566                 return 0;
 567         }
 568
 569         dev = set->crtc->dev;
 570
 571         drm_warn_on_modeset_not_all_locked(dev);
 572
 573         /*
 574          * Allocate space for the backup of all (non-pointer) encoder and
 575          * connector data.
 576          */
 577         save_encoders = kzalloc(dev->mode_config.num_encoder *
 578                                 sizeof(struct drm_encoder), GFP_KERNEL);
 579         if (!save_encoders)
 580                 return -ENOMEM;
 581
 582         save_connectors = kzalloc(dev->mode_config.num_connector *
 583                                 sizeof(struct drm_connector), GFP_KERNEL);
 584         if (!save_connectors) {
 585                 kfree(save_encoders);
 586                 return -ENOMEM;
 587         }
 588
 589         /*
 590          * Copy data. Note that driver private data is not affected.
 591          * Should anything bad happen only the expected state is
 592          * restored, not the drivers personal bookkeeping.
 593          */
 594         count = 0;
 595         drm_for_each_encoder(encoder, dev) {
 596                 save_encoders[count++] = *encoder;
 597         }
 598
 599         count = 0;
 600         drm_for_each_connector(connector, dev) {
 601                 save_connectors[count++] = *connector;
 602         }
 603
 604         save_set.crtc = set->crtc;
 605         save_set.mode = &set->crtc->mode;
 606         save_set.x = set->crtc->x;
 607         save_set.y = set->crtc->y;
 608         save_set.fb = set->crtc->primary->fb;
 609
 610         /* We should be able to check here if the fb has the same properties
 611          * and then just flip_or_move it */
 612         if (set->crtc->primary->fb != set->fb) {
 613                 /* If we have no fb then treat it as a full mode set */
 614                 if (set->crtc->primary->fb == NULL) {
 615                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 616                         mode_changed = true;
 617                 } else if (set->fb->pixel_format !=
 618                            set->crtc->primary->fb->pixel_format) {
 619                         mode_changed = true;
 620                 } else
 621                         fb_changed = true;
 622         }
 623
 624         if (set->x != set->crtc->x || set->y != set->crtc->y)
 625                 fb_changed = true;
 626
 627         if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
 628                 DRM_DEBUG_KMS("modes are different, full mode set\n");
 629                 drm_mode_debug_printmodeline(&set->crtc->mode);
 630                 drm_mode_debug_printmodeline(set->mode);
 631                 mode_changed = true;
 632         }
 633
 634         /* take a reference on all connectors in set */
 635         for (ro = 0; ro < set->num_connectors; ro++) {
 636                 drm_connector_reference(set->connectors[ro]);
 637         }
 638
 639         /* a) traverse passed in connector list and get encoders for them */
 640         count = 0;
 641         drm_for_each_connector(connector, dev) {
 642                 const struct drm_connector_helper_funcs *connector_funcs =
 643                         connector->helper_private;
 644                 new_encoder = connector->encoder;
 645                 for (ro = 0; ro < set->num_connectors; ro++) {
 646                         if (set->connectors[ro] == connector) {
 647                                 new_encoder = connector_funcs->best_encoder(connector);
 648                                 /* if we can't get an encoder for a connector
 649                                    we are setting now - then fail */
 650                                 if (new_encoder == NULL)
 651                                         /* don't break so fail path works correct */
 652                                         fail = 1;
 653
 654                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
 655                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 656                                         mode_changed = true;
 657                                 }
 658
 659                                 break;
 660                         }
 661                 }
 662
 663                 if (new_encoder != connector->encoder) {
 664                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 665                         mode_changed = true;
 666                         /* If the encoder is reused for another connector, then
 667                          * the appropriate crtc will be set later.
 668                          */
 669                         if (connector->encoder)
 670                                 connector->encoder->crtc = NULL;
 671                         connector->encoder = new_encoder;
 672                 }
 673         }
 674
 675         if (fail) {
 676                 ret = -EINVAL;
 677                 goto fail;
 678         }
 679
 680         count = 0;
 681         drm_for_each_connector(connector, dev) {
 682                 if (!connector->encoder)
 683                         continue;
 684
 685                 if (connector->encoder->crtc == set->crtc)
 686                         new_crtc = NULL;
 687                 else
 688                         new_crtc = connector->encoder->crtc;
 689
 690                 for (ro = 0; ro < set->num_connectors; ro++) {
 691                         if (set->connectors[ro] == connector)
 692                                 new_crtc = set->crtc;
 693                 }
 694
 695                 /* Make sure the new CRTC will work with the encoder */
 696                 if (new_crtc &&
 697                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 698                         ret = -EINVAL;
 699                         goto fail;
 700                 }
 701                 if (new_crtc != connector->encoder->crtc) {
 702                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 703                         mode_changed = true;
 704                         connector->encoder->crtc = new_crtc;
 705                 }
 706                 if (new_crtc) {
 707                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
 708                                       connector->base.id, connector->name,
 709                                       new_crtc->base.id, new_crtc->name);
 710                 } else {
 711                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 712                                       connector->base.id, connector->name);
 713                 }
 714         }
 715
 716         /* mode_set_base is not a required function */
 717         if (fb_changed && !crtc_funcs->mode_set_base)
 718                 mode_changed = true;
 719
 720         if (mode_changed) {
 721                 if (drm_helper_crtc_in_use(set->crtc)) {
 722                         DRM_DEBUG_KMS("attempting to set mode from"
 723                                         " userspace\n");
 724                         drm_mode_debug_printmodeline(set->mode);
 725                         set->crtc->primary->fb = set->fb;
 726                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 727                                                       set->x, set->y,
 728                                                       save_set.fb)) {
 729                                 DRM_ERROR("failed to set mode on [CRTC:%d:%s]\n",
 730                                           set->crtc->base.id, set->crtc->name);
 731                                 set->crtc->primary->fb = save_set.fb;
 732                                 ret = -EINVAL;
 733                                 goto fail;
 734                         }
 735                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 736                         for (i = 0; i < set->num_connectors; i++) {
 737                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 738                                               set->connectors[i]->name);
 739                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 740                         }
 741                 }
 742                 __drm_helper_disable_unused_functions(dev);
 743         } else if (fb_changed) {
 744                 set->crtc->x = set->x;
 745                 set->crtc->y = set->y;
 746                 set->crtc->primary->fb = set->fb;
 747                 ret = crtc_funcs->mode_set_base(set->crtc,
 748                                                 set->x, set->y, save_set.fb);
 749                 if (ret != 0) {
 750                         set->crtc->x = save_set.x;
 751                         set->crtc->y = save_set.y;
 752                         set->crtc->primary->fb = save_set.fb;
 753                         goto fail;
 754                 }
 755         }
 756
 757         /* after fail drop reference on all connectors in save set */
 758         count = 0;
 759         drm_for_each_connector(connector, dev) {
 760                 drm_connector_unreference(&save_connectors[count++]);
 761         }
 762
 763         kfree(save_connectors);
 764         kfree(save_encoders);
 765         return 0;
 766
 767 fail:
 768         /* Restore all previous data. */
 769         count = 0;
 770         drm_for_each_encoder(encoder, dev) {
 771                 *encoder = save_encoders[count++];
 772         }
 773
 774         count = 0;
 775         drm_for_each_connector(connector, dev) {
 776                 *connector = save_connectors[count++];
 777         }
 778
 779         /* after fail drop reference on all connectors in set */
 780         for (ro = 0; ro < set->num_connectors; ro++) {
 781                 drm_connector_unreference(set->connectors[ro]);
 782         }
 783
 784         /* Try to restore the config */
 785         if (mode_changed &&
 786             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 787                                       save_set.y, save_set.fb))
 788                 DRM_ERROR("failed to restore config after modeset failure\n");
 789
 790         kfree(save_connectors);
 791         kfree(save_encoders);
 792         return ret;
 793 }
 794 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 795
 796 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 797 {
 798         int dpms = DRM_MODE_DPMS_OFF;
 799         struct drm_connector *connector;
 800         struct drm_device *dev = encoder->dev;
 801
 802         drm_for_each_connector(connector, dev)
 803                 if (connector->encoder == encoder)
 804                         if (connector->dpms < dpms)
 805                                 dpms = connector->dpms;
 806         return dpms;
 807 }
 808
 809 /* Helper which handles bridge ordering around encoder dpms */
 810 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 811 {
 812         struct drm_bridge *bridge = encoder->bridge;
 813         const struct drm_encoder_helper_funcs *encoder_funcs;
 814
 815         encoder_funcs = encoder->helper_private;
 816         if (!encoder_funcs)
 817                 return;
 818
 819         if (mode == DRM_MODE_DPMS_ON)
 820                 drm_bridge_pre_enable(bridge);
 821         else
 822                 drm_bridge_disable(bridge);
 823
 824         if (encoder_funcs->dpms)
 825                 encoder_funcs->dpms(encoder, mode);
 826
 827         if (mode == DRM_MODE_DPMS_ON)
 828                 drm_bridge_enable(bridge);
 829         else
 830                 drm_bridge_post_disable(bridge);
 831 }
 832
 833 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 834 {
 835         int dpms = DRM_MODE_DPMS_OFF;
 836         struct drm_connector *connector;
 837         struct drm_device *dev = crtc->dev;
 838
 839         drm_for_each_connector(connector, dev)
 840                 if (connector->encoder && connector->encoder->crtc == crtc)
 841                         if (connector->dpms < dpms)
 842                                 dpms = connector->dpms;
 843         return dpms;
 844 }
 845
 846 /**
 847  * drm_helper_connector_dpms() - connector dpms helper implementation
 848  * @connector: affected connector
 849  * @mode: DPMS mode
 850  *
 851  * The drm_helper_connector_dpms() helper function implements the ->dpms()
 852  * callback of struct &drm_connector_funcs for drivers using the legacy CRTC helpers.
 853  *
 854  * This is the main helper function provided by the CRTC helper framework for
 855  * implementing the DPMS connector attribute. It computes the new desired DPMS
 856  * state for all encoders and CRTCs in the output mesh and calls the ->dpms()
 857  * callbacks provided by the driver in struct &drm_crtc_helper_funcs and struct
 858  * &drm_encoder_helper_funcs appropriately.
 859  *
 860  * This function is deprecated.  New drivers must implement atomic modeset
 861  * support, for which this function is unsuitable. Instead drivers should use
 862  * drm_atomic_helper_connector_dpms().
 863  *
 864  * Returns:
 865  * Always returns 0.
 866  */
 867 int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 868 {
 869         struct drm_encoder *encoder = connector->encoder;
 870         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 871         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 872
 873         if (mode == connector->dpms)
 874                 return 0;
 875
 876         old_dpms = connector->dpms;
 877         connector->dpms = mode;
 878
 879         if (encoder)
 880                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 881
 882         /* from off to on, do crtc then encoder */
 883         if (mode < old_dpms) {
 884                 if (crtc) {
 885                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 886                         if (crtc_funcs->dpms)
 887                                 (*crtc_funcs->dpms) (crtc,
 888                                                      drm_helper_choose_crtc_dpms(crtc));
 889                 }
 890                 if (encoder)
 891                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 892         }
 893
 894         /* from on to off, do encoder then crtc */
 895         if (mode > old_dpms) {
 896                 if (encoder)
 897                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 898                 if (crtc) {
 899                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 900                         if (crtc_funcs->dpms)
 901                                 (*crtc_funcs->dpms) (crtc,
 902                                                      drm_helper_choose_crtc_dpms(crtc));
 903                 }
 904         }
 905
 906         return 0;
 907 }
 908 EXPORT_SYMBOL(drm_helper_connector_dpms);
 909
 910 /**
 911  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
 912  * @fb: drm_framebuffer object to fill out
 913  * @mode_cmd: metadata from the userspace fb creation request
 914  *
 915  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
 916  * metadata fields.
 917  */
 918 void drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
 919                                     const struct drm_mode_fb_cmd2 *mode_cmd)
 920 {
 921         int i;
 922
 923         fb->width = mode_cmd->width;
 924         fb->height = mode_cmd->height;
 925         for (i = 0; i < 4; i++) {
 926                 fb->pitches[i] = mode_cmd->pitches[i];
 927                 fb->offsets[i] = mode_cmd->offsets[i];
 928                 fb->modifier[i] = mode_cmd->modifier[i];
 929         }
 930         drm_fb_get_bpp_depth(mode_cmd->pixel_format, &fb->depth,
 931                                     &fb->bits_per_pixel);
 932         fb->pixel_format = mode_cmd->pixel_format;
 933         fb->flags = mode_cmd->flags;
 934 }
 935 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
 936
 937 /**
 938  * drm_helper_resume_force_mode - force-restore mode setting configuration
 939  * @dev: drm_device which should be restored
 940  *
 941  * Drivers which use the mode setting helpers can use this function to
 942  * force-restore the mode setting configuration e.g. on resume or when something
 943  * else might have trampled over the hw state (like some overzealous old BIOSen
 944  * tended to do).
 945  *
 946  * This helper doesn't provide a error return value since restoring the old
 947  * config should never fail due to resource allocation issues since the driver
 948  * has successfully set the restored configuration already. Hence this should
 949  * boil down to the equivalent of a few dpms on calls, which also don't provide
 950  * an error code.
 951  *
 952  * Drivers where simply restoring an old configuration again might fail (e.g.
 953  * due to slight differences in allocating shared resources when the
 954  * configuration is restored in a different order than when userspace set it up)
 955  * need to use their own restore logic.
 956  *
 957  * This function is deprecated. New drivers should implement atomic mode-
 958  * setting and use the atomic suspend/resume helpers.
 959  *
 960  * See also:
 961  * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 962  */
 963 void drm_helper_resume_force_mode(struct drm_device *dev)
 964 {
 965         struct drm_crtc *crtc;
 966         struct drm_encoder *encoder;
 967         const struct drm_crtc_helper_funcs *crtc_funcs;
 968         int encoder_dpms;
 969         bool ret;
 970
 971         drm_modeset_lock_all(dev);
 972         drm_for_each_crtc(crtc, dev) {
 973
 974                 if (!crtc->enabled)
 975                         continue;
 976
 977                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 978                                                crtc->x, crtc->y, crtc->primary->fb);
 979
 980                 /* Restoring the old config should never fail! */
 981                 if (ret == false)
 982                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 983
 984                 /* Turn off outputs that were already powered off */
 985                 if (drm_helper_choose_crtc_dpms(crtc)) {
 986                         drm_for_each_encoder(encoder, dev) {
 987
 988                                 if(encoder->crtc != crtc)
 989                                         continue;
 990
 991                                 encoder_dpms = drm_helper_choose_encoder_dpms(
 992                                                         encoder);
 993
 994                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
 995                         }
 996
 997                         crtc_funcs = crtc->helper_private;
 998                         if (crtc_funcs->dpms)
 999                                 (*crtc_funcs->dpms) (crtc,
1000                                                      drm_helper_choose_crtc_dpms(crtc));
1001                 }
1002         }
1003
1004         /* disable the unused connectors while restoring the modesetting */
1005         __drm_helper_disable_unused_functions(dev);
1006         drm_modeset_unlock_all(dev);
1007 }
1008 EXPORT_SYMBOL(drm_helper_resume_force_mode);
1009
1010 /**
1011  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
1012  * @crtc: DRM CRTC
1013  * @mode: DRM display mode which userspace requested
1014  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
1015  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1016  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1017  * @old_fb: previous framebuffer
1018  *
1019  * This function implements a callback useable as the ->mode_set callback
1020  * required by the CRTC helpers. Besides the atomic plane helper functions for
1021  * the primary plane the driver must also provide the ->mode_set_nofb callback
1022  * to set up the CRTC.
1023  *
1024  * This is a transitional helper useful for converting drivers to the atomic
1025  * interfaces.
1026  */
1027 int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
1028                              struct drm_display_mode *adjusted_mode, int x, int y,
1029                              struct drm_framebuffer *old_fb)
1030 {
1031         struct drm_crtc_state *crtc_state;
1032         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
1033         int ret;
1034
1035         if (crtc->funcs->atomic_duplicate_state)
1036                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
1037         else {
1038                 if (!crtc->state)
1039                         drm_atomic_helper_crtc_reset(crtc);
1040
1041                 crtc_state = drm_atomic_helper_crtc_duplicate_state(crtc);
1042         }
1043
1044         if (!crtc_state)
1045                 return -ENOMEM;
1046
1047         crtc_state->planes_changed = true;
1048         crtc_state->mode_changed = true;
1049         ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
1050         if (ret)
1051                 goto out;
1052         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
1053
1054         if (crtc_funcs->atomic_check) {
1055                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
1056                 if (ret)
1057                         goto out;
1058         }
1059
1060         swap(crtc->state, crtc_state);
1061
1062         crtc_funcs->mode_set_nofb(crtc);
1063
1064         ret = drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
1065
1066 out:
1067         if (crtc_state) {
1068                 if (crtc->funcs->atomic_destroy_state)
1069                         crtc->funcs->atomic_destroy_state(crtc, crtc_state);
1070                 else
1071                         drm_atomic_helper_crtc_destroy_state(crtc, crtc_state);
1072         }
1073
1074         return ret;
1075 }
1076 EXPORT_SYMBOL(drm_helper_crtc_mode_set);
1077
1078 /**
1079  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
1080  * @crtc: DRM CRTC
1081  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1082  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1083  * @old_fb: previous framebuffer
1084  *
1085  * This function implements a callback useable as the ->mode_set_base used
1086  * required by the CRTC helpers. The driver must provide the atomic plane helper
1087  * functions for the primary plane.
1088  *
1089  * This is a transitional helper useful for converting drivers to the atomic
1090  * interfaces.
1091  */
1092 int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
1093                                   struct drm_framebuffer *old_fb)
1094 {
1095         struct drm_plane_state *plane_state;
1096         struct drm_plane *plane = crtc->primary;
1097
1098         if (plane->funcs->atomic_duplicate_state)
1099                 plane_state = plane->funcs->atomic_duplicate_state(plane);
1100         else {
1101                 if (!plane->state)
1102                         drm_atomic_helper_plane_reset(plane);
1103
1104                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
1105         }
1106         if (!plane_state)
1107                 return -ENOMEM;
1108         plane_state->plane = plane;
1109
1110         plane_state->crtc = crtc;
1111         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
1112         plane_state->crtc_x = 0;
1113         plane_state->crtc_y = 0;
1114         plane_state->crtc_h = crtc->mode.vdisplay;
1115         plane_state->crtc_w = crtc->mode.hdisplay;
1116         plane_state->src_x = x << 16;
1117         plane_state->src_y = y << 16;
1118         plane_state->src_h = crtc->mode.vdisplay << 16;
1119         plane_state->src_w = crtc->mode.hdisplay << 16;
1120
1121         return drm_plane_helper_commit(plane, plane_state, old_fb);
1122 }
1123 EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);
1124
1125 /**
1126  * drm_helper_crtc_enable_color_mgmt - enable color management properties
1127  * @crtc: DRM CRTC
1128  * @degamma_lut_size: the size of the degamma lut (before CSC)
1129  * @gamma_lut_size: the size of the gamma lut (after CSC)
1130  *
1131  * This function lets the driver enable the color correction properties on a
1132  * CRTC. This includes 3 degamma, csc and gamma properties that userspace can
1133  * set and 2 size properties to inform the userspace of the lut sizes.
1134  */
1135 void drm_helper_crtc_enable_color_mgmt(struct drm_crtc *crtc,
1136                                        int degamma_lut_size,
1137                                        int gamma_lut_size)
1138 {
1139         struct drm_device *dev = crtc->dev;
1140         struct drm_mode_config *config = &dev->mode_config;
1141
1142         drm_object_attach_property(&crtc->base,
1143                                    config->degamma_lut_property, 0);
1144         drm_object_attach_property(&crtc->base,
1145                                    config->ctm_property, 0);
1146         drm_object_attach_property(&crtc->base,
1147                                    config->gamma_lut_property, 0);
1148
1149         drm_object_attach_property(&crtc->base,
1150                                    config->degamma_lut_size_property,
1151                                    degamma_lut_size);
1152         drm_object_attach_property(&crtc->base,
1153                                    config->gamma_lut_size_property,
1154                                    gamma_lut_size);
1155 }
1156 EXPORT_SYMBOL(drm_helper_crtc_enable_color_mgmt);