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                         /* we keep a reference while the encoder is bound */
 461                         drm_connector_unreference(connector);
 462                 }
 463         }
 464
 465         __drm_helper_disable_unused_functions(dev);
 466 }
 467
 468 /**
 469  * drm_crtc_helper_set_config - set a new config from userspace
 470  * @set: mode set configuration
 471  *
 472  * The drm_crtc_helper_set_config() helper function implements the set_config
 473  * callback of struct &drm_crtc_funcs for drivers using the legacy CRTC helpers.
 474  *
 475  * It first tries to locate the best encoder for each connector by calling the
 476  * connector ->best_encoder() (struct &drm_connector_helper_funcs) helper
 477  * operation.
 478  *
 479  * After locating the appropriate encoders, the helper function will call the
 480  * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
 481  * or reject it completely in which case an error will be returned to the
 482  * application. If the new configuration after mode adjustment is identical to
 483  * the current configuration the helper function will return without performing
 484  * any other operation.
 485  *
 486  * If the adjusted mode is identical to the current mode but changes to the
 487  * frame buffer need to be applied, the drm_crtc_helper_set_config() function
 488  * will call the CRTC ->mode_set_base() (struct &drm_crtc_helper_funcs) helper
 489  * operation.
 490  *
 491  * If the adjusted mode differs from the current mode, or if the
 492  * ->mode_set_base() helper operation is not provided, the helper function
 493  * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
 494  * and ->commit() CRTC and encoder helper operations, in that order.
 495  * Alternatively it can also use the dpms and disable helper operations. For
 496  * details see struct &drm_crtc_helper_funcs and struct
 497  * &drm_encoder_helper_funcs.
 498  *
 499  * This function is deprecated.  New drivers must implement atomic modeset
 500  * support, for which this function is unsuitable. Instead drivers should use
 501  * drm_atomic_helper_set_config().
 502  *
 503  * Returns:
 504  * Returns 0 on success, negative errno numbers on failure.
 505  */
 506 int drm_crtc_helper_set_config(struct drm_mode_set *set)
 507 {
 508         struct drm_device *dev;
 509         struct drm_crtc *new_crtc;
 510         struct drm_encoder *save_encoders, *new_encoder, *encoder;
 511         bool mode_changed = false; /* if true do a full mode set */
 512         bool fb_changed = false; /* if true and !mode_changed just do a flip */
 513         struct drm_connector *save_connectors, *connector;
 514         int count = 0, ro, fail = 0;
 515         const struct drm_crtc_helper_funcs *crtc_funcs;
 516         struct drm_mode_set save_set;
 517         int ret;
 518         int i;
 519
 520         DRM_DEBUG_KMS("\n");
 521
 522         BUG_ON(!set);
 523         BUG_ON(!set->crtc);
 524         BUG_ON(!set->crtc->helper_private);
 525
 526         /* Enforce sane interface api - has been abused by the fb helper. */
 527         BUG_ON(!set->mode && set->fb);
 528         BUG_ON(set->fb && set->num_connectors == 0);
 529
 530         crtc_funcs = set->crtc->helper_private;
 531
 532         if (!set->mode)
 533                 set->fb = NULL;
 534
 535         if (set->fb) {
 536                 DRM_DEBUG_KMS("[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 537                               set->crtc->base.id, set->crtc->name,
 538                               set->fb->base.id,
 539                               (int)set->num_connectors, set->x, set->y);
 540         } else {
 541                 DRM_DEBUG_KMS("[CRTC:%d:%s] [NOFB]\n",
 542                               set->crtc->base.id, set->crtc->name);
 543                 drm_crtc_helper_disable(set->crtc);
 544                 return 0;
 545         }
 546
 547         dev = set->crtc->dev;
 548
 549         drm_warn_on_modeset_not_all_locked(dev);
 550
 551         /*
 552          * Allocate space for the backup of all (non-pointer) encoder and
 553          * connector data.
 554          */
 555         save_encoders = kzalloc(dev->mode_config.num_encoder *
 556                                 sizeof(struct drm_encoder), GFP_KERNEL);
 557         if (!save_encoders)
 558                 return -ENOMEM;
 559
 560         save_connectors = kzalloc(dev->mode_config.num_connector *
 561                                 sizeof(struct drm_connector), GFP_KERNEL);
 562         if (!save_connectors) {
 563                 kfree(save_encoders);
 564                 return -ENOMEM;
 565         }
 566
 567         /*
 568          * Copy data. Note that driver private data is not affected.
 569          * Should anything bad happen only the expected state is
 570          * restored, not the drivers personal bookkeeping.
 571          */
 572         count = 0;
 573         drm_for_each_encoder(encoder, dev) {
 574                 save_encoders[count++] = *encoder;
 575         }
 576
 577         count = 0;
 578         drm_for_each_connector(connector, dev) {
 579                 save_connectors[count++] = *connector;
 580         }
 581
 582         save_set.crtc = set->crtc;
 583         save_set.mode = &set->crtc->mode;
 584         save_set.x = set->crtc->x;
 585         save_set.y = set->crtc->y;
 586         save_set.fb = set->crtc->primary->fb;
 587
 588         /* We should be able to check here if the fb has the same properties
 589          * and then just flip_or_move it */
 590         if (set->crtc->primary->fb != set->fb) {
 591                 /* If we have no fb then treat it as a full mode set */
 592                 if (set->crtc->primary->fb == NULL) {
 593                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 594                         mode_changed = true;
 595                 } else if (set->fb->pixel_format !=
 596                            set->crtc->primary->fb->pixel_format) {
 597                         mode_changed = true;
 598                 } else
 599                         fb_changed = true;
 600         }
 601
 602         if (set->x != set->crtc->x || set->y != set->crtc->y)
 603                 fb_changed = true;
 604
 605         if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
 606                 DRM_DEBUG_KMS("modes are different, full mode set\n");
 607                 drm_mode_debug_printmodeline(&set->crtc->mode);
 608                 drm_mode_debug_printmodeline(set->mode);
 609                 mode_changed = true;
 610         }
 611
 612         /* take a reference on all connectors in set */
 613         for (ro = 0; ro < set->num_connectors; ro++) {
 614                 drm_connector_reference(set->connectors[ro]);
 615         }
 616
 617         /* a) traverse passed in connector list and get encoders for them */
 618         count = 0;
 619         drm_for_each_connector(connector, dev) {
 620                 const struct drm_connector_helper_funcs *connector_funcs =
 621                         connector->helper_private;
 622                 new_encoder = connector->encoder;
 623                 for (ro = 0; ro < set->num_connectors; ro++) {
 624                         if (set->connectors[ro] == connector) {
 625                                 new_encoder = connector_funcs->best_encoder(connector);
 626                                 /* if we can't get an encoder for a connector
 627                                    we are setting now - then fail */
 628                                 if (new_encoder == NULL)
 629                                         /* don't break so fail path works correct */
 630                                         fail = 1;
 631
 632                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
 633                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 634                                         mode_changed = true;
 635                                 }
 636
 637                                 break;
 638                         }
 639                 }
 640
 641                 if (new_encoder != connector->encoder) {
 642                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 643                         mode_changed = true;
 644                         /* If the encoder is reused for another connector, then
 645                          * the appropriate crtc will be set later.
 646                          */
 647                         if (connector->encoder)
 648                                 connector->encoder->crtc = NULL;
 649                         connector->encoder = new_encoder;
 650                 }
 651         }
 652
 653         if (fail) {
 654                 ret = -EINVAL;
 655                 goto fail;
 656         }
 657
 658         count = 0;
 659         drm_for_each_connector(connector, dev) {
 660                 if (!connector->encoder)
 661                         continue;
 662
 663                 if (connector->encoder->crtc == set->crtc)
 664                         new_crtc = NULL;
 665                 else
 666                         new_crtc = connector->encoder->crtc;
 667
 668                 for (ro = 0; ro < set->num_connectors; ro++) {
 669                         if (set->connectors[ro] == connector)
 670                                 new_crtc = set->crtc;
 671                 }
 672
 673                 /* Make sure the new CRTC will work with the encoder */
 674                 if (new_crtc &&
 675                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 676                         ret = -EINVAL;
 677                         goto fail;
 678                 }
 679                 if (new_crtc != connector->encoder->crtc) {
 680                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 681                         mode_changed = true;
 682                         connector->encoder->crtc = new_crtc;
 683                 }
 684                 if (new_crtc) {
 685                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
 686                                       connector->base.id, connector->name,
 687                                       new_crtc->base.id, new_crtc->name);
 688                 } else {
 689                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 690                                       connector->base.id, connector->name);
 691                 }
 692         }
 693
 694         /* mode_set_base is not a required function */
 695         if (fb_changed && !crtc_funcs->mode_set_base)
 696                 mode_changed = true;
 697
 698         if (mode_changed) {
 699                 if (drm_helper_crtc_in_use(set->crtc)) {
 700                         DRM_DEBUG_KMS("attempting to set mode from"
 701                                         " userspace\n");
 702                         drm_mode_debug_printmodeline(set->mode);
 703                         set->crtc->primary->fb = set->fb;
 704                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 705                                                       set->x, set->y,
 706                                                       save_set.fb)) {
 707                                 DRM_ERROR("failed to set mode on [CRTC:%d:%s]\n",
 708                                           set->crtc->base.id, set->crtc->name);
 709                                 set->crtc->primary->fb = save_set.fb;
 710                                 ret = -EINVAL;
 711                                 goto fail;
 712                         }
 713                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 714                         for (i = 0; i < set->num_connectors; i++) {
 715                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 716                                               set->connectors[i]->name);
 717                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 718                         }
 719                 }
 720                 __drm_helper_disable_unused_functions(dev);
 721         } else if (fb_changed) {
 722                 set->crtc->x = set->x;
 723                 set->crtc->y = set->y;
 724                 set->crtc->primary->fb = set->fb;
 725                 ret = crtc_funcs->mode_set_base(set->crtc,
 726                                                 set->x, set->y, save_set.fb);
 727                 if (ret != 0) {
 728                         set->crtc->x = save_set.x;
 729                         set->crtc->y = save_set.y;
 730                         set->crtc->primary->fb = save_set.fb;
 731                         goto fail;
 732                 }
 733         }
 734
 735         /* after fail drop reference on all connectors in save set */
 736         count = 0;
 737         drm_for_each_connector(connector, dev) {
 738                 drm_connector_unreference(&save_connectors[count++]);
 739         }
 740
 741         kfree(save_connectors);
 742         kfree(save_encoders);
 743         return 0;
 744
 745 fail:
 746         /* Restore all previous data. */
 747         count = 0;
 748         drm_for_each_encoder(encoder, dev) {
 749                 *encoder = save_encoders[count++];
 750         }
 751
 752         count = 0;
 753         drm_for_each_connector(connector, dev) {
 754                 *connector = save_connectors[count++];
 755         }
 756
 757         /* after fail drop reference on all connectors in set */
 758         for (ro = 0; ro < set->num_connectors; ro++) {
 759                 drm_connector_unreference(set->connectors[ro]);
 760         }
 761
 762         /* Try to restore the config */
 763         if (mode_changed &&
 764             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 765                                       save_set.y, save_set.fb))
 766                 DRM_ERROR("failed to restore config after modeset failure\n");
 767
 768         kfree(save_connectors);
 769         kfree(save_encoders);
 770         return ret;
 771 }
 772 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 773
 774 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 775 {
 776         int dpms = DRM_MODE_DPMS_OFF;
 777         struct drm_connector *connector;
 778         struct drm_device *dev = encoder->dev;
 779
 780         drm_for_each_connector(connector, dev)
 781                 if (connector->encoder == encoder)
 782                         if (connector->dpms < dpms)
 783                                 dpms = connector->dpms;
 784         return dpms;
 785 }
 786
 787 /* Helper which handles bridge ordering around encoder dpms */
 788 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 789 {
 790         struct drm_bridge *bridge = encoder->bridge;
 791         const struct drm_encoder_helper_funcs *encoder_funcs;
 792
 793         if (mode == DRM_MODE_DPMS_ON)
 794                 drm_bridge_pre_enable(bridge);
 795         else
 796                 drm_bridge_disable(bridge);
 797
 798         encoder_funcs = encoder->helper_private;
 799         if (encoder_funcs->dpms)
 800                 encoder_funcs->dpms(encoder, mode);
 801
 802         if (mode == DRM_MODE_DPMS_ON)
 803                 drm_bridge_enable(bridge);
 804         else
 805                 drm_bridge_post_disable(bridge);
 806 }
 807
 808 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 809 {
 810         int dpms = DRM_MODE_DPMS_OFF;
 811         struct drm_connector *connector;
 812         struct drm_device *dev = crtc->dev;
 813
 814         drm_for_each_connector(connector, dev)
 815                 if (connector->encoder && connector->encoder->crtc == crtc)
 816                         if (connector->dpms < dpms)
 817                                 dpms = connector->dpms;
 818         return dpms;
 819 }
 820
 821 /**
 822  * drm_helper_connector_dpms() - connector dpms helper implementation
 823  * @connector: affected connector
 824  * @mode: DPMS mode
 825  *
 826  * The drm_helper_connector_dpms() helper function implements the ->dpms()
 827  * callback of struct &drm_connector_funcs for drivers using the legacy CRTC helpers.
 828  *
 829  * This is the main helper function provided by the CRTC helper framework for
 830  * implementing the DPMS connector attribute. It computes the new desired DPMS
 831  * state for all encoders and CRTCs in the output mesh and calls the ->dpms()
 832  * callbacks provided by the driver in struct &drm_crtc_helper_funcs and struct
 833  * &drm_encoder_helper_funcs appropriately.
 834  *
 835  * This function is deprecated.  New drivers must implement atomic modeset
 836  * support, for which this function is unsuitable. Instead drivers should use
 837  * drm_atomic_helper_connector_dpms().
 838  *
 839  * Returns:
 840  * Always returns 0.
 841  */
 842 int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 843 {
 844         struct drm_encoder *encoder = connector->encoder;
 845         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 846         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 847
 848         if (mode == connector->dpms)
 849                 return 0;
 850
 851         old_dpms = connector->dpms;
 852         connector->dpms = mode;
 853
 854         if (encoder)
 855                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 856
 857         /* from off to on, do crtc then encoder */
 858         if (mode < old_dpms) {
 859                 if (crtc) {
 860                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 861                         if (crtc_funcs->dpms)
 862                                 (*crtc_funcs->dpms) (crtc,
 863                                                      drm_helper_choose_crtc_dpms(crtc));
 864                 }
 865                 if (encoder)
 866                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 867         }
 868
 869         /* from on to off, do encoder then crtc */
 870         if (mode > old_dpms) {
 871                 if (encoder)
 872                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 873                 if (crtc) {
 874                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 875                         if (crtc_funcs->dpms)
 876                                 (*crtc_funcs->dpms) (crtc,
 877                                                      drm_helper_choose_crtc_dpms(crtc));
 878                 }
 879         }
 880
 881         return 0;
 882 }
 883 EXPORT_SYMBOL(drm_helper_connector_dpms);
 884
 885 /**
 886  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
 887  * @fb: drm_framebuffer object to fill out
 888  * @mode_cmd: metadata from the userspace fb creation request
 889  *
 890  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
 891  * metadata fields.
 892  */
 893 void drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
 894                                     const struct drm_mode_fb_cmd2 *mode_cmd)
 895 {
 896         int i;
 897
 898         fb->width = mode_cmd->width;
 899         fb->height = mode_cmd->height;
 900         for (i = 0; i < 4; i++) {
 901                 fb->pitches[i] = mode_cmd->pitches[i];
 902                 fb->offsets[i] = mode_cmd->offsets[i];
 903                 fb->modifier[i] = mode_cmd->modifier[i];
 904         }
 905         drm_fb_get_bpp_depth(mode_cmd->pixel_format, &fb->depth,
 906                                     &fb->bits_per_pixel);
 907         fb->pixel_format = mode_cmd->pixel_format;
 908         fb->flags = mode_cmd->flags;
 909 }
 910 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
 911
 912 /**
 913  * drm_helper_resume_force_mode - force-restore mode setting configuration
 914  * @dev: drm_device which should be restored
 915  *
 916  * Drivers which use the mode setting helpers can use this function to
 917  * force-restore the mode setting configuration e.g. on resume or when something
 918  * else might have trampled over the hw state (like some overzealous old BIOSen
 919  * tended to do).
 920  *
 921  * This helper doesn't provide a error return value since restoring the old
 922  * config should never fail due to resource allocation issues since the driver
 923  * has successfully set the restored configuration already. Hence this should
 924  * boil down to the equivalent of a few dpms on calls, which also don't provide
 925  * an error code.
 926  *
 927  * Drivers where simply restoring an old configuration again might fail (e.g.
 928  * due to slight differences in allocating shared resources when the
 929  * configuration is restored in a different order than when userspace set it up)
 930  * need to use their own restore logic.
 931  *
 932  * This function is deprecated. New drivers should implement atomic mode-
 933  * setting and use the atomic suspend/resume helpers.
 934  *
 935  * See also:
 936  * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 937  */
 938 void drm_helper_resume_force_mode(struct drm_device *dev)
 939 {
 940         struct drm_crtc *crtc;
 941         struct drm_encoder *encoder;
 942         const struct drm_crtc_helper_funcs *crtc_funcs;
 943         int encoder_dpms;
 944         bool ret;
 945
 946         drm_modeset_lock_all(dev);
 947         drm_for_each_crtc(crtc, dev) {
 948
 949                 if (!crtc->enabled)
 950                         continue;
 951
 952                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 953                                                crtc->x, crtc->y, crtc->primary->fb);
 954
 955                 /* Restoring the old config should never fail! */
 956                 if (ret == false)
 957                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 958
 959                 /* Turn off outputs that were already powered off */
 960                 if (drm_helper_choose_crtc_dpms(crtc)) {
 961                         drm_for_each_encoder(encoder, dev) {
 962
 963                                 if(encoder->crtc != crtc)
 964                                         continue;
 965
 966                                 encoder_dpms = drm_helper_choose_encoder_dpms(
 967                                                         encoder);
 968
 969                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
 970                         }
 971
 972                         crtc_funcs = crtc->helper_private;
 973                         if (crtc_funcs->dpms)
 974                                 (*crtc_funcs->dpms) (crtc,
 975                                                      drm_helper_choose_crtc_dpms(crtc));
 976                 }
 977         }
 978
 979         /* disable the unused connectors while restoring the modesetting */
 980         __drm_helper_disable_unused_functions(dev);
 981         drm_modeset_unlock_all(dev);
 982 }
 983 EXPORT_SYMBOL(drm_helper_resume_force_mode);
 984
 985 /**
 986  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
 987  * @crtc: DRM CRTC
 988  * @mode: DRM display mode which userspace requested
 989  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
 990  * @x: x offset of the CRTC scanout area on the underlying framebuffer
 991  * @y: y offset of the CRTC scanout area on the underlying framebuffer
 992  * @old_fb: previous framebuffer
 993  *
 994  * This function implements a callback useable as the ->mode_set callback
 995  * required by the CRTC helpers. Besides the atomic plane helper functions for
 996  * the primary plane the driver must also provide the ->mode_set_nofb callback
 997  * to set up the CRTC.
 998  *
 999  * This is a transitional helper useful for converting drivers to the atomic
1000  * interfaces.
1001  */
1002 int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
1003                              struct drm_display_mode *adjusted_mode, int x, int y,
1004                              struct drm_framebuffer *old_fb)
1005 {
1006         struct drm_crtc_state *crtc_state;
1007         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
1008         int ret;
1009
1010         if (crtc->funcs->atomic_duplicate_state)
1011                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
1012         else {
1013                 if (!crtc->state)
1014                         drm_atomic_helper_crtc_reset(crtc);
1015
1016                 crtc_state = drm_atomic_helper_crtc_duplicate_state(crtc);
1017         }
1018
1019         if (!crtc_state)
1020                 return -ENOMEM;
1021
1022         crtc_state->planes_changed = true;
1023         crtc_state->mode_changed = true;
1024         ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
1025         if (ret)
1026                 goto out;
1027         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
1028
1029         if (crtc_funcs->atomic_check) {
1030                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
1031                 if (ret)
1032                         goto out;
1033         }
1034
1035         swap(crtc->state, crtc_state);
1036
1037         crtc_funcs->mode_set_nofb(crtc);
1038
1039         ret = drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
1040
1041 out:
1042         if (crtc_state) {
1043                 if (crtc->funcs->atomic_destroy_state)
1044                         crtc->funcs->atomic_destroy_state(crtc, crtc_state);
1045                 else
1046                         drm_atomic_helper_crtc_destroy_state(crtc, crtc_state);
1047         }
1048
1049         return ret;
1050 }
1051 EXPORT_SYMBOL(drm_helper_crtc_mode_set);
1052
1053 /**
1054  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
1055  * @crtc: DRM CRTC
1056  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1057  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1058  * @old_fb: previous framebuffer
1059  *
1060  * This function implements a callback useable as the ->mode_set_base used
1061  * required by the CRTC helpers. The driver must provide the atomic plane helper
1062  * functions for the primary plane.
1063  *
1064  * This is a transitional helper useful for converting drivers to the atomic
1065  * interfaces.
1066  */
1067 int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
1068                                   struct drm_framebuffer *old_fb)
1069 {
1070         struct drm_plane_state *plane_state;
1071         struct drm_plane *plane = crtc->primary;
1072
1073         if (plane->funcs->atomic_duplicate_state)
1074                 plane_state = plane->funcs->atomic_duplicate_state(plane);
1075         else {
1076                 if (!plane->state)
1077                         drm_atomic_helper_plane_reset(plane);
1078
1079                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
1080         }
1081         if (!plane_state)
1082                 return -ENOMEM;
1083         plane_state->plane = plane;
1084
1085         plane_state->crtc = crtc;
1086         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
1087         plane_state->crtc_x = 0;
1088         plane_state->crtc_y = 0;
1089         plane_state->crtc_h = crtc->mode.vdisplay;
1090         plane_state->crtc_w = crtc->mode.hdisplay;
1091         plane_state->src_x = x << 16;
1092         plane_state->src_y = y << 16;
1093         plane_state->src_h = crtc->mode.vdisplay << 16;
1094         plane_state->src_w = crtc->mode.hdisplay << 16;
1095
1096         return drm_plane_helper_commit(plane, plane_state, old_fb);
1097 }
1098 EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);
1099
1100 /**
1101  * drm_helper_crtc_enable_color_mgmt - enable color management properties
1102  * @crtc: DRM CRTC
1103  * @degamma_lut_size: the size of the degamma lut (before CSC)
1104  * @gamma_lut_size: the size of the gamma lut (after CSC)
1105  *
1106  * This function lets the driver enable the color correction properties on a
1107  * CRTC. This includes 3 degamma, csc and gamma properties that userspace can
1108  * set and 2 size properties to inform the userspace of the lut sizes.
1109  */
1110 void drm_helper_crtc_enable_color_mgmt(struct drm_crtc *crtc,
1111                                        int degamma_lut_size,
1112                                        int gamma_lut_size)
1113 {
1114         struct drm_device *dev = crtc->dev;
1115         struct drm_mode_config *config = &dev->mode_config;
1116
1117         drm_object_attach_property(&crtc->base,
1118                                    config->degamma_lut_property, 0);
1119         drm_object_attach_property(&crtc->base,
1120                                    config->ctm_property, 0);
1121         drm_object_attach_property(&crtc->base,
1122                                    config->gamma_lut_property, 0);
1123
1124         drm_object_attach_property(&crtc->base,
1125                                    config->degamma_lut_size_property,
1126                                    degamma_lut_size);
1127         drm_object_attach_property(&crtc->base,
1128                                    config->gamma_lut_size_property,
1129                                    gamma_lut_size);
1130 }
1131 EXPORT_SYMBOL(drm_helper_crtc_enable_color_mgmt);