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         drm_bridge_disable(encoder->bridge);
 174
 175         if (encoder_funcs->disable)
 176                 (*encoder_funcs->disable)(encoder);
 177         else
 178                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 179
 180         drm_bridge_post_disable(encoder->bridge);
 181 }
 182
 183 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 184 {
 185         struct drm_encoder *encoder;
 186         struct drm_crtc *crtc;
 187
 188         drm_warn_on_modeset_not_all_locked(dev);
 189
 190         drm_for_each_encoder(encoder, dev) {
 191                 if (!drm_helper_encoder_in_use(encoder)) {
 192                         drm_encoder_disable(encoder);
 193                         /* disconnect encoder from any connector */
 194                         encoder->crtc = NULL;
 195                 }
 196         }
 197
 198         drm_for_each_crtc(crtc, dev) {
 199                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 200                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 201                 if (!crtc->enabled) {
 202                         if (crtc_funcs->disable)
 203                                 (*crtc_funcs->disable)(crtc);
 204                         else
 205                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 206                         crtc->primary->fb = NULL;
 207                 }
 208         }
 209 }
 210
 211 /**
 212  * drm_helper_disable_unused_functions - disable unused objects
 213  * @dev: DRM device
 214  *
 215  * This function walks through the entire mode setting configuration of @dev. It
 216  * will remove any CRTC links of unused encoders and encoder links of
 217  * disconnected connectors. Then it will disable all unused encoders and CRTCs
 218  * either by calling their disable callback if available or by calling their
 219  * dpms callback with DRM_MODE_DPMS_OFF.
 220  *
 221  * NOTE:
 222  *
 223  * This function is part of the legacy modeset helper library and will cause
 224  * major confusion with atomic drivers. This is because atomic helpers guarantee
 225  * to never call ->disable() hooks on a disabled function, or ->enable() hooks
 226  * on an enabled functions. drm_helper_disable_unused_functions() on the other
 227  * hand throws such guarantees into the wind and calls disable hooks
 228  * unconditionally on unused functions.
 229  */
 230 void drm_helper_disable_unused_functions(struct drm_device *dev)
 231 {
 232         drm_modeset_lock_all(dev);
 233         __drm_helper_disable_unused_functions(dev);
 234         drm_modeset_unlock_all(dev);
 235 }
 236 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 237
 238 /*
 239  * Check the CRTC we're going to map each output to vs. its current
 240  * CRTC.  If they don't match, we have to disable the output and the CRTC
 241  * since the driver will have to re-route things.
 242  */
 243 static void
 244 drm_crtc_prepare_encoders(struct drm_device *dev)
 245 {
 246         const struct drm_encoder_helper_funcs *encoder_funcs;
 247         struct drm_encoder *encoder;
 248
 249         drm_for_each_encoder(encoder, dev) {
 250                 encoder_funcs = encoder->helper_private;
 251                 /* Disable unused encoders */
 252                 if (encoder->crtc == NULL)
 253                         drm_encoder_disable(encoder);
 254                 /* Disable encoders whose CRTC is about to change */
 255                 if (encoder_funcs->get_crtc &&
 256                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
 257                         drm_encoder_disable(encoder);
 258         }
 259 }
 260
 261 /**
 262  * drm_crtc_helper_set_mode - internal helper to set a mode
 263  * @crtc: CRTC to program
 264  * @mode: mode to use
 265  * @x: horizontal offset into the surface
 266  * @y: vertical offset into the surface
 267  * @old_fb: old framebuffer, for cleanup
 268  *
 269  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 270  * to fixup or reject the mode prior to trying to set it. This is an internal
 271  * helper that drivers could e.g. use to update properties that require the
 272  * entire output pipe to be disabled and re-enabled in a new configuration. For
 273  * example for changing whether audio is enabled on a hdmi link or for changing
 274  * panel fitter or dither attributes. It is also called by the
 275  * drm_crtc_helper_set_config() helper function to drive the mode setting
 276  * sequence.
 277  *
 278  * Returns:
 279  * True if the mode was set successfully, false otherwise.
 280  */
 281 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 282                               struct drm_display_mode *mode,
 283                               int x, int y,
 284                               struct drm_framebuffer *old_fb)
 285 {
 286         struct drm_device *dev = crtc->dev;
 287         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
 288         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 289         const struct drm_encoder_helper_funcs *encoder_funcs;
 290         int saved_x, saved_y;
 291         bool saved_enabled;
 292         struct drm_encoder *encoder;
 293         bool ret = true;
 294
 295         drm_warn_on_modeset_not_all_locked(dev);
 296
 297         saved_enabled = crtc->enabled;
 298         crtc->enabled = drm_helper_crtc_in_use(crtc);
 299         if (!crtc->enabled)
 300                 return true;
 301
 302         adjusted_mode = drm_mode_duplicate(dev, mode);
 303         if (!adjusted_mode) {
 304                 crtc->enabled = saved_enabled;
 305                 return false;
 306         }
 307
 308         saved_mode = crtc->mode;
 309         saved_hwmode = crtc->hwmode;
 310         saved_x = crtc->x;
 311         saved_y = crtc->y;
 312
 313         /* Update crtc values up front so the driver can rely on them for mode
 314          * setting.
 315          */
 316         crtc->mode = *mode;
 317         crtc->x = x;
 318         crtc->y = y;
 319
 320         /* Pass our mode to the connectors and the CRTC to give them a chance to
 321          * adjust it according to limitations or connector properties, and also
 322          * a chance to reject the mode entirely.
 323          */
 324         drm_for_each_encoder(encoder, dev) {
 325
 326                 if (encoder->crtc != crtc)
 327                         continue;
 328
 329                 ret = drm_bridge_mode_fixup(encoder->bridge,
 330                         mode, adjusted_mode);
 331                 if (!ret) {
 332                         DRM_DEBUG_KMS("Bridge fixup failed\n");
 333                         goto done;
 334                 }
 335
 336                 encoder_funcs = encoder->helper_private;
 337                 if (encoder_funcs->mode_fixup) {
 338                         if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 339                                                               adjusted_mode))) {
 340                                 DRM_DEBUG_KMS("Encoder fixup failed\n");
 341                                 goto done;
 342                         }
 343                 }
 344         }
 345
 346         if (crtc_funcs->mode_fixup) {
 347                 if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
 348                                                 adjusted_mode))) {
 349                         DRM_DEBUG_KMS("CRTC fixup failed\n");
 350                         goto done;
 351                 }
 352         }
 353         DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
 354
 355         crtc->hwmode = *adjusted_mode;
 356
 357         /* Prepare the encoders and CRTCs before setting the mode. */
 358         drm_for_each_encoder(encoder, dev) {
 359
 360                 if (encoder->crtc != crtc)
 361                         continue;
 362
 363                 drm_bridge_disable(encoder->bridge);
 364
 365                 encoder_funcs = encoder->helper_private;
 366                 /* Disable the encoders as the first thing we do. */
 367                 encoder_funcs->prepare(encoder);
 368
 369                 drm_bridge_post_disable(encoder->bridge);
 370         }
 371
 372         drm_crtc_prepare_encoders(dev);
 373
 374         crtc_funcs->prepare(crtc);
 375
 376         /* Set up the DPLL and any encoders state that needs to adjust or depend
 377          * on the DPLL.
 378          */
 379         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 380         if (!ret)
 381             goto done;
 382
 383         drm_for_each_encoder(encoder, dev) {
 384
 385                 if (encoder->crtc != crtc)
 386                         continue;
 387
 388                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
 389                         encoder->base.id, encoder->name,
 390                         mode->base.id, mode->name);
 391                 encoder_funcs = encoder->helper_private;
 392                 encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 393
 394                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
 395         }
 396
 397         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 398         crtc_funcs->commit(crtc);
 399
 400         drm_for_each_encoder(encoder, dev) {
 401
 402                 if (encoder->crtc != crtc)
 403                         continue;
 404
 405                 drm_bridge_pre_enable(encoder->bridge);
 406
 407                 encoder_funcs = encoder->helper_private;
 408                 encoder_funcs->commit(encoder);
 409
 410                 drm_bridge_enable(encoder->bridge);
 411         }
 412
 413         /* Calculate and store various constants which
 414          * are later needed by vblank and swap-completion
 415          * timestamping. They are derived from true hwmode.
 416          */
 417         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 418
 419         /* FIXME: add subpixel order */
 420 done:
 421         drm_mode_destroy(dev, adjusted_mode);
 422         if (!ret) {
 423                 crtc->enabled = saved_enabled;
 424                 crtc->mode = saved_mode;
 425                 crtc->hwmode = saved_hwmode;
 426                 crtc->x = saved_x;
 427                 crtc->y = saved_y;
 428         }
 429
 430         return ret;
 431 }
 432 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 433
 434 static void
 435 drm_crtc_helper_disable(struct drm_crtc *crtc)
 436 {
 437         struct drm_device *dev = crtc->dev;
 438         struct drm_connector *connector;
 439         struct drm_encoder *encoder;
 440
 441         /* Decouple all encoders and their attached connectors from this crtc */
 442         drm_for_each_encoder(encoder, dev) {
 443                 if (encoder->crtc != crtc)
 444                         continue;
 445
 446                 drm_for_each_connector(connector, dev) {
 447                         if (connector->encoder != encoder)
 448                                 continue;
 449
 450                         connector->encoder = NULL;
 451
 452                         /*
 453                          * drm_helper_disable_unused_functions() ought to be
 454                          * doing this, but since we've decoupled the encoder
 455                          * from the connector above, the required connection
 456                          * between them is henceforth no longer available.
 457                          */
 458                         connector->dpms = DRM_MODE_DPMS_OFF;
 459                 }
 460         }
 461
 462         __drm_helper_disable_unused_functions(dev);
 463 }
 464
 465 /**
 466  * drm_crtc_helper_set_config - set a new config from userspace
 467  * @set: mode set configuration
 468  *
 469  * The drm_crtc_helper_set_config() helper function implements the set_config
 470  * callback of struct &drm_crtc_funcs for drivers using the legacy CRTC helpers.
 471  *
 472  * It first tries to locate the best encoder for each connector by calling the
 473  * connector ->best_encoder() (struct &drm_connector_helper_funcs) helper
 474  * operation.
 475  *
 476  * After locating the appropriate encoders, the helper function will call the
 477  * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
 478  * or reject it completely in which case an error will be returned to the
 479  * application. If the new configuration after mode adjustment is identical to
 480  * the current configuration the helper function will return without performing
 481  * any other operation.
 482  *
 483  * If the adjusted mode is identical to the current mode but changes to the
 484  * frame buffer need to be applied, the drm_crtc_helper_set_config() function
 485  * will call the CRTC ->mode_set_base() (struct &drm_crtc_helper_funcs) helper
 486  * operation.
 487  *
 488  * If the adjusted mode differs from the current mode, or if the
 489  * ->mode_set_base() helper operation is not provided, the helper function
 490  * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
 491  * and ->commit() CRTC and encoder helper operations, in that order.
 492  * Alternatively it can also use the dpms and disable helper operations. For
 493  * details see struct &drm_crtc_helper_funcs and struct
 494  * &drm_encoder_helper_funcs.
 495  *
 496  * This function is deprecated.  New drivers must implement atomic modeset
 497  * support, for which this function is unsuitable. Instead drivers should use
 498  * drm_atomic_helper_set_config().
 499  *
 500  * Returns:
 501  * Returns 0 on success, negative errno numbers on failure.
 502  */
 503 int drm_crtc_helper_set_config(struct drm_mode_set *set)
 504 {
 505         struct drm_device *dev;
 506         struct drm_crtc *new_crtc;
 507         struct drm_encoder *save_encoders, *new_encoder, *encoder;
 508         bool mode_changed = false; /* if true do a full mode set */
 509         bool fb_changed = false; /* if true and !mode_changed just do a flip */
 510         struct drm_connector *save_connectors, *connector;
 511         int count = 0, ro, fail = 0;
 512         const struct drm_crtc_helper_funcs *crtc_funcs;
 513         struct drm_mode_set save_set;
 514         int ret;
 515         int i;
 516
 517         DRM_DEBUG_KMS("\n");
 518
 519         BUG_ON(!set);
 520         BUG_ON(!set->crtc);
 521         BUG_ON(!set->crtc->helper_private);
 522
 523         /* Enforce sane interface api - has been abused by the fb helper. */
 524         BUG_ON(!set->mode && set->fb);
 525         BUG_ON(set->fb && set->num_connectors == 0);
 526
 527         crtc_funcs = set->crtc->helper_private;
 528
 529         if (!set->mode)
 530                 set->fb = NULL;
 531
 532         if (set->fb) {
 533                 DRM_DEBUG_KMS("[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 534                               set->crtc->base.id, set->crtc->name,
 535                               set->fb->base.id,
 536                               (int)set->num_connectors, set->x, set->y);
 537         } else {
 538                 DRM_DEBUG_KMS("[CRTC:%d:%s] [NOFB]\n",
 539                               set->crtc->base.id, set->crtc->name);
 540                 drm_crtc_helper_disable(set->crtc);
 541                 return 0;
 542         }
 543
 544         dev = set->crtc->dev;
 545
 546         drm_warn_on_modeset_not_all_locked(dev);
 547
 548         /*
 549          * Allocate space for the backup of all (non-pointer) encoder and
 550          * connector data.
 551          */
 552         save_encoders = kzalloc(dev->mode_config.num_encoder *
 553                                 sizeof(struct drm_encoder), GFP_KERNEL);
 554         if (!save_encoders)
 555                 return -ENOMEM;
 556
 557         save_connectors = kzalloc(dev->mode_config.num_connector *
 558                                 sizeof(struct drm_connector), GFP_KERNEL);
 559         if (!save_connectors) {
 560                 kfree(save_encoders);
 561                 return -ENOMEM;
 562         }
 563
 564         /*
 565          * Copy data. Note that driver private data is not affected.
 566          * Should anything bad happen only the expected state is
 567          * restored, not the drivers personal bookkeeping.
 568          */
 569         count = 0;
 570         drm_for_each_encoder(encoder, dev) {
 571                 save_encoders[count++] = *encoder;
 572         }
 573
 574         count = 0;
 575         drm_for_each_connector(connector, dev) {
 576                 save_connectors[count++] = *connector;
 577         }
 578
 579         save_set.crtc = set->crtc;
 580         save_set.mode = &set->crtc->mode;
 581         save_set.x = set->crtc->x;
 582         save_set.y = set->crtc->y;
 583         save_set.fb = set->crtc->primary->fb;
 584
 585         /* We should be able to check here if the fb has the same properties
 586          * and then just flip_or_move it */
 587         if (set->crtc->primary->fb != set->fb) {
 588                 /* If we have no fb then treat it as a full mode set */
 589                 if (set->crtc->primary->fb == NULL) {
 590                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 591                         mode_changed = true;
 592                 } else if (set->fb->pixel_format !=
 593                            set->crtc->primary->fb->pixel_format) {
 594                         mode_changed = true;
 595                 } else
 596                         fb_changed = true;
 597         }
 598
 599         if (set->x != set->crtc->x || set->y != set->crtc->y)
 600                 fb_changed = true;
 601
 602         if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
 603                 DRM_DEBUG_KMS("modes are different, full mode set\n");
 604                 drm_mode_debug_printmodeline(&set->crtc->mode);
 605                 drm_mode_debug_printmodeline(set->mode);
 606                 mode_changed = true;
 607         }
 608
 609         /* a) traverse passed in connector list and get encoders for them */
 610         count = 0;
 611         drm_for_each_connector(connector, dev) {
 612                 const struct drm_connector_helper_funcs *connector_funcs =
 613                         connector->helper_private;
 614                 new_encoder = connector->encoder;
 615                 for (ro = 0; ro < set->num_connectors; ro++) {
 616                         if (set->connectors[ro] == connector) {
 617                                 new_encoder = connector_funcs->best_encoder(connector);
 618                                 /* if we can't get an encoder for a connector
 619                                    we are setting now - then fail */
 620                                 if (new_encoder == NULL)
 621                                         /* don't break so fail path works correct */
 622                                         fail = 1;
 623
 624                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
 625                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 626                                         mode_changed = true;
 627                                 }
 628
 629                                 break;
 630                         }
 631                 }
 632
 633                 if (new_encoder != connector->encoder) {
 634                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 635                         mode_changed = true;
 636                         /* If the encoder is reused for another connector, then
 637                          * the appropriate crtc will be set later.
 638                          */
 639                         if (connector->encoder)
 640                                 connector->encoder->crtc = NULL;
 641                         connector->encoder = new_encoder;
 642                 }
 643         }
 644
 645         if (fail) {
 646                 ret = -EINVAL;
 647                 goto fail;
 648         }
 649
 650         count = 0;
 651         drm_for_each_connector(connector, dev) {
 652                 if (!connector->encoder)
 653                         continue;
 654
 655                 if (connector->encoder->crtc == set->crtc)
 656                         new_crtc = NULL;
 657                 else
 658                         new_crtc = connector->encoder->crtc;
 659
 660                 for (ro = 0; ro < set->num_connectors; ro++) {
 661                         if (set->connectors[ro] == connector)
 662                                 new_crtc = set->crtc;
 663                 }
 664
 665                 /* Make sure the new CRTC will work with the encoder */
 666                 if (new_crtc &&
 667                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 668                         ret = -EINVAL;
 669                         goto fail;
 670                 }
 671                 if (new_crtc != connector->encoder->crtc) {
 672                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 673                         mode_changed = true;
 674                         connector->encoder->crtc = new_crtc;
 675                 }
 676                 if (new_crtc) {
 677                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
 678                                       connector->base.id, connector->name,
 679                                       new_crtc->base.id, new_crtc->name);
 680                 } else {
 681                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 682                                       connector->base.id, connector->name);
 683                 }
 684         }
 685
 686         /* mode_set_base is not a required function */
 687         if (fb_changed && !crtc_funcs->mode_set_base)
 688                 mode_changed = true;
 689
 690         if (mode_changed) {
 691                 if (drm_helper_crtc_in_use(set->crtc)) {
 692                         DRM_DEBUG_KMS("attempting to set mode from"
 693                                         " userspace\n");
 694                         drm_mode_debug_printmodeline(set->mode);
 695                         set->crtc->primary->fb = set->fb;
 696                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 697                                                       set->x, set->y,
 698                                                       save_set.fb)) {
 699                                 DRM_ERROR("failed to set mode on [CRTC:%d:%s]\n",
 700                                           set->crtc->base.id, set->crtc->name);
 701                                 set->crtc->primary->fb = save_set.fb;
 702                                 ret = -EINVAL;
 703                                 goto fail;
 704                         }
 705                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 706                         for (i = 0; i < set->num_connectors; i++) {
 707                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 708                                               set->connectors[i]->name);
 709                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 710                         }
 711                 }
 712                 __drm_helper_disable_unused_functions(dev);
 713         } else if (fb_changed) {
 714                 set->crtc->x = set->x;
 715                 set->crtc->y = set->y;
 716                 set->crtc->primary->fb = set->fb;
 717                 ret = crtc_funcs->mode_set_base(set->crtc,
 718                                                 set->x, set->y, save_set.fb);
 719                 if (ret != 0) {
 720                         set->crtc->x = save_set.x;
 721                         set->crtc->y = save_set.y;
 722                         set->crtc->primary->fb = save_set.fb;
 723                         goto fail;
 724                 }
 725         }
 726
 727         kfree(save_connectors);
 728         kfree(save_encoders);
 729         return 0;
 730
 731 fail:
 732         /* Restore all previous data. */
 733         count = 0;
 734         drm_for_each_encoder(encoder, dev) {
 735                 *encoder = save_encoders[count++];
 736         }
 737
 738         count = 0;
 739         drm_for_each_connector(connector, dev) {
 740                 *connector = save_connectors[count++];
 741         }
 742
 743         /* Try to restore the config */
 744         if (mode_changed &&
 745             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 746                                       save_set.y, save_set.fb))
 747                 DRM_ERROR("failed to restore config after modeset failure\n");
 748
 749         kfree(save_connectors);
 750         kfree(save_encoders);
 751         return ret;
 752 }
 753 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 754
 755 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 756 {
 757         int dpms = DRM_MODE_DPMS_OFF;
 758         struct drm_connector *connector;
 759         struct drm_device *dev = encoder->dev;
 760
 761         drm_for_each_connector(connector, dev)
 762                 if (connector->encoder == encoder)
 763                         if (connector->dpms < dpms)
 764                                 dpms = connector->dpms;
 765         return dpms;
 766 }
 767
 768 /* Helper which handles bridge ordering around encoder dpms */
 769 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 770 {
 771         struct drm_bridge *bridge = encoder->bridge;
 772         const struct drm_encoder_helper_funcs *encoder_funcs;
 773
 774         if (mode == DRM_MODE_DPMS_ON)
 775                 drm_bridge_pre_enable(bridge);
 776         else
 777                 drm_bridge_disable(bridge);
 778
 779         encoder_funcs = encoder->helper_private;
 780         if (encoder_funcs->dpms)
 781                 encoder_funcs->dpms(encoder, mode);
 782
 783         if (mode == DRM_MODE_DPMS_ON)
 784                 drm_bridge_enable(bridge);
 785         else
 786                 drm_bridge_post_disable(bridge);
 787 }
 788
 789 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 790 {
 791         int dpms = DRM_MODE_DPMS_OFF;
 792         struct drm_connector *connector;
 793         struct drm_device *dev = crtc->dev;
 794
 795         drm_for_each_connector(connector, dev)
 796                 if (connector->encoder && connector->encoder->crtc == crtc)
 797                         if (connector->dpms < dpms)
 798                                 dpms = connector->dpms;
 799         return dpms;
 800 }
 801
 802 /**
 803  * drm_helper_connector_dpms() - connector dpms helper implementation
 804  * @connector: affected connector
 805  * @mode: DPMS mode
 806  *
 807  * The drm_helper_connector_dpms() helper function implements the ->dpms()
 808  * callback of struct &drm_connector_funcs for drivers using the legacy CRTC helpers.
 809  *
 810  * This is the main helper function provided by the CRTC helper framework for
 811  * implementing the DPMS connector attribute. It computes the new desired DPMS
 812  * state for all encoders and CRTCs in the output mesh and calls the ->dpms()
 813  * callbacks provided by the driver in struct &drm_crtc_helper_funcs and struct
 814  * &drm_encoder_helper_funcs appropriately.
 815  *
 816  * This function is deprecated.  New drivers must implement atomic modeset
 817  * support, for which this function is unsuitable. Instead drivers should use
 818  * drm_atomic_helper_connector_dpms().
 819  *
 820  * Returns:
 821  * Always returns 0.
 822  */
 823 int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 824 {
 825         struct drm_encoder *encoder = connector->encoder;
 826         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 827         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 828
 829         if (mode == connector->dpms)
 830                 return 0;
 831
 832         old_dpms = connector->dpms;
 833         connector->dpms = mode;
 834
 835         if (encoder)
 836                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 837
 838         /* from off to on, do crtc then encoder */
 839         if (mode < old_dpms) {
 840                 if (crtc) {
 841                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 842                         if (crtc_funcs->dpms)
 843                                 (*crtc_funcs->dpms) (crtc,
 844                                                      drm_helper_choose_crtc_dpms(crtc));
 845                 }
 846                 if (encoder)
 847                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 848         }
 849
 850         /* from on to off, do encoder then crtc */
 851         if (mode > old_dpms) {
 852                 if (encoder)
 853                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 854                 if (crtc) {
 855                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 856                         if (crtc_funcs->dpms)
 857                                 (*crtc_funcs->dpms) (crtc,
 858                                                      drm_helper_choose_crtc_dpms(crtc));
 859                 }
 860         }
 861
 862         return 0;
 863 }
 864 EXPORT_SYMBOL(drm_helper_connector_dpms);
 865
 866 /**
 867  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
 868  * @fb: drm_framebuffer object to fill out
 869  * @mode_cmd: metadata from the userspace fb creation request
 870  *
 871  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
 872  * metadata fields.
 873  */
 874 void drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
 875                                     const struct drm_mode_fb_cmd2 *mode_cmd)
 876 {
 877         int i;
 878
 879         fb->width = mode_cmd->width;
 880         fb->height = mode_cmd->height;
 881         for (i = 0; i < 4; i++) {
 882                 fb->pitches[i] = mode_cmd->pitches[i];
 883                 fb->offsets[i] = mode_cmd->offsets[i];
 884                 fb->modifier[i] = mode_cmd->modifier[i];
 885         }
 886         drm_fb_get_bpp_depth(mode_cmd->pixel_format, &fb->depth,
 887                                     &fb->bits_per_pixel);
 888         fb->pixel_format = mode_cmd->pixel_format;
 889         fb->flags = mode_cmd->flags;
 890 }
 891 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
 892
 893 /**
 894  * drm_helper_resume_force_mode - force-restore mode setting configuration
 895  * @dev: drm_device which should be restored
 896  *
 897  * Drivers which use the mode setting helpers can use this function to
 898  * force-restore the mode setting configuration e.g. on resume or when something
 899  * else might have trampled over the hw state (like some overzealous old BIOSen
 900  * tended to do).
 901  *
 902  * This helper doesn't provide a error return value since restoring the old
 903  * config should never fail due to resource allocation issues since the driver
 904  * has successfully set the restored configuration already. Hence this should
 905  * boil down to the equivalent of a few dpms on calls, which also don't provide
 906  * an error code.
 907  *
 908  * Drivers where simply restoring an old configuration again might fail (e.g.
 909  * due to slight differences in allocating shared resources when the
 910  * configuration is restored in a different order than when userspace set it up)
 911  * need to use their own restore logic.
 912  *
 913  * This function is deprecated. New drivers should implement atomic mode-
 914  * setting and use the atomic suspend/resume helpers.
 915  *
 916  * See also:
 917  * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 918  */
 919 void drm_helper_resume_force_mode(struct drm_device *dev)
 920 {
 921         struct drm_crtc *crtc;
 922         struct drm_encoder *encoder;
 923         const struct drm_crtc_helper_funcs *crtc_funcs;
 924         int encoder_dpms;
 925         bool ret;
 926
 927         drm_modeset_lock_all(dev);
 928         drm_for_each_crtc(crtc, dev) {
 929
 930                 if (!crtc->enabled)
 931                         continue;
 932
 933                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 934                                                crtc->x, crtc->y, crtc->primary->fb);
 935
 936                 /* Restoring the old config should never fail! */
 937                 if (ret == false)
 938                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 939
 940                 /* Turn off outputs that were already powered off */
 941                 if (drm_helper_choose_crtc_dpms(crtc)) {
 942                         drm_for_each_encoder(encoder, dev) {
 943
 944                                 if(encoder->crtc != crtc)
 945                                         continue;
 946
 947                                 encoder_dpms = drm_helper_choose_encoder_dpms(
 948                                                         encoder);
 949
 950                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
 951                         }
 952
 953                         crtc_funcs = crtc->helper_private;
 954                         if (crtc_funcs->dpms)
 955                                 (*crtc_funcs->dpms) (crtc,
 956                                                      drm_helper_choose_crtc_dpms(crtc));
 957                 }
 958         }
 959
 960         /* disable the unused connectors while restoring the modesetting */
 961         __drm_helper_disable_unused_functions(dev);
 962         drm_modeset_unlock_all(dev);
 963 }
 964 EXPORT_SYMBOL(drm_helper_resume_force_mode);
 965
 966 /**
 967  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
 968  * @crtc: DRM CRTC
 969  * @mode: DRM display mode which userspace requested
 970  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
 971  * @x: x offset of the CRTC scanout area on the underlying framebuffer
 972  * @y: y offset of the CRTC scanout area on the underlying framebuffer
 973  * @old_fb: previous framebuffer
 974  *
 975  * This function implements a callback useable as the ->mode_set callback
 976  * required by the CRTC helpers. Besides the atomic plane helper functions for
 977  * the primary plane the driver must also provide the ->mode_set_nofb callback
 978  * to set up the CRTC.
 979  *
 980  * This is a transitional helper useful for converting drivers to the atomic
 981  * interfaces.
 982  */
 983 int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
 984                              struct drm_display_mode *adjusted_mode, int x, int y,
 985                              struct drm_framebuffer *old_fb)
 986 {
 987         struct drm_crtc_state *crtc_state;
 988         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 989         int ret;
 990
 991         if (crtc->funcs->atomic_duplicate_state)
 992                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
 993         else {
 994                 if (!crtc->state)
 995                         drm_atomic_helper_crtc_reset(crtc);
 996
 997                 crtc_state = drm_atomic_helper_crtc_duplicate_state(crtc);
 998         }
 999
1000         if (!crtc_state)
1001                 return -ENOMEM;
1002
1003         crtc_state->planes_changed = true;
1004         crtc_state->mode_changed = true;
1005         ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
1006         if (ret)
1007                 goto out;
1008         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
1009
1010         if (crtc_funcs->atomic_check) {
1011                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
1012                 if (ret)
1013                         goto out;
1014         }
1015
1016         swap(crtc->state, crtc_state);
1017
1018         crtc_funcs->mode_set_nofb(crtc);
1019
1020         ret = drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
1021
1022 out:
1023         if (crtc_state) {
1024                 if (crtc->funcs->atomic_destroy_state)
1025                         crtc->funcs->atomic_destroy_state(crtc, crtc_state);
1026                 else
1027                         drm_atomic_helper_crtc_destroy_state(crtc, crtc_state);
1028         }
1029
1030         return ret;
1031 }
1032 EXPORT_SYMBOL(drm_helper_crtc_mode_set);
1033
1034 /**
1035  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
1036  * @crtc: DRM CRTC
1037  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1038  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1039  * @old_fb: previous framebuffer
1040  *
1041  * This function implements a callback useable as the ->mode_set_base used
1042  * required by the CRTC helpers. The driver must provide the atomic plane helper
1043  * functions for the primary plane.
1044  *
1045  * This is a transitional helper useful for converting drivers to the atomic
1046  * interfaces.
1047  */
1048 int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
1049                                   struct drm_framebuffer *old_fb)
1050 {
1051         struct drm_plane_state *plane_state;
1052         struct drm_plane *plane = crtc->primary;
1053
1054         if (plane->funcs->atomic_duplicate_state)
1055                 plane_state = plane->funcs->atomic_duplicate_state(plane);
1056         else if (plane->state)
1057                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
1058         else
1059                 plane_state = kzalloc(sizeof(*plane_state), GFP_KERNEL);
1060         if (!plane_state)
1061                 return -ENOMEM;
1062         plane_state->plane = plane;
1063
1064         plane_state->crtc = crtc;
1065         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
1066         plane_state->crtc_x = 0;
1067         plane_state->crtc_y = 0;
1068         plane_state->crtc_h = crtc->mode.vdisplay;
1069         plane_state->crtc_w = crtc->mode.hdisplay;
1070         plane_state->src_x = x << 16;
1071         plane_state->src_y = y << 16;
1072         plane_state->src_h = crtc->mode.vdisplay << 16;
1073         plane_state->src_w = crtc->mode.hdisplay << 16;
1074
1075         return drm_plane_helper_commit(plane, plane_state, old_fb);
1076 }
1077 EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);
1078
1079 /**
1080  * drm_helper_crtc_enable_color_mgmt - enable color management properties
1081  * @crtc: DRM CRTC
1082  * @degamma_lut_size: the size of the degamma lut (before CSC)
1083  * @gamma_lut_size: the size of the gamma lut (after CSC)
1084  *
1085  * This function lets the driver enable the color correction properties on a
1086  * CRTC. This includes 3 degamma, csc and gamma properties that userspace can
1087  * set and 2 size properties to inform the userspace of the lut sizes.
1088  */
1089 void drm_helper_crtc_enable_color_mgmt(struct drm_crtc *crtc,
1090                                        int degamma_lut_size,
1091                                        int gamma_lut_size)
1092 {
1093         struct drm_device *dev = crtc->dev;
1094         struct drm_mode_config *config = &dev->mode_config;
1095
1096         drm_object_attach_property(&crtc->base,
1097                                    config->degamma_lut_property, 0);
1098         drm_object_attach_property(&crtc->base,
1099                                    config->ctm_property, 0);
1100         drm_object_attach_property(&crtc->base,
1101                                    config->gamma_lut_property, 0);
1102
1103         drm_object_attach_property(&crtc->base,
1104                                    config->degamma_lut_size_property,
1105                                    degamma_lut_size);
1106         drm_object_attach_property(&crtc->base,
1107                                    config->gamma_lut_size_property,
1108                                    gamma_lut_size);
1109 }
1110 EXPORT_SYMBOL(drm_helper_crtc_enable_color_mgmt);