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_encoder.h>
  40 #include <drm/drm_fourcc.h>
  41 #include <drm/drm_crtc_helper.h>
  42 #include <drm/drm_fb_helper.h>
  43 #include <drm/drm_plane_helper.h>
  44 #include <drm/drm_atomic_helper.h>
  45 #include <drm/drm_edid.h>
  46
  47 /**
  48  * DOC: overview
  49  *
  50  * The CRTC modeset helper library provides a default set_config implementation
  51  * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
  52  * the same callbacks which drivers can use to e.g. restore the modeset
  53  * configuration on resume with drm_helper_resume_force_mode().
  54  *
  55  * Note that this helper library doesn't track the current power state of CRTCs
  56  * and encoders. It can call callbacks like ->dpms() even though the hardware is
  57  * already in the desired state. This deficiency has been fixed in the atomic
  58  * helpers.
  59  *
  60  * The driver callbacks are mostly compatible with the atomic modeset helpers,
  61  * except for the handling of the primary plane: Atomic helpers require that the
  62  * primary plane is implemented as a real standalone plane and not directly tied
  63  * to the CRTC state. For easier transition this library provides functions to
  64  * implement the old semantics required by the CRTC helpers using the new plane
  65  * and atomic helper callbacks.
  66  *
  67  * Drivers are strongly urged to convert to the atomic helpers (by way of first
  68  * converting to the plane helpers). New drivers must not use these functions
  69  * but need to implement the atomic interface instead, potentially using the
  70  * atomic helpers for that.
  71  *
  72  * These legacy modeset helpers use the same function table structures as
  73  * all other modesetting helpers. See the documentation for struct
  74  * &drm_crtc_helper_funcs, struct &drm_encoder_helper_funcs and struct
  75  * &drm_connector_helper_funcs.
  76  */
  77
  78 /**
  79  * drm_helper_encoder_in_use - check if a given encoder is in use
  80  * @encoder: encoder to check
  81  *
  82  * Checks whether @encoder is with the current mode setting output configuration
  83  * in use by any connector. This doesn't mean that it is actually enabled since
  84  * the DPMS state is tracked separately.
  85  *
  86  * Returns:
  87  * True if @encoder is used, false otherwise.
  88  */
  89 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
  90 {
  91         struct drm_connector *connector;
  92         struct drm_device *dev = encoder->dev;
  93
  94         /*
  95          * We can expect this mutex to be locked if we are not panicking.
  96          * Locking is currently fubar in the panic handler.
  97          */
  98         if (!oops_in_progress) {
  99                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 100                 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 101         }
 102
 103         drm_for_each_connector(connector, dev)
 104                 if (connector->encoder == encoder)
 105                         return true;
 106         return false;
 107 }
 108 EXPORT_SYMBOL(drm_helper_encoder_in_use);
 109
 110 /**
 111  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 112  * @crtc: CRTC to check
 113  *
 114  * Checks whether @crtc is with the current mode setting output configuration
 115  * in use by any connector. This doesn't mean that it is actually enabled since
 116  * the DPMS state is tracked separately.
 117  *
 118  * Returns:
 119  * True if @crtc is used, false otherwise.
 120  */
 121 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 122 {
 123         struct drm_encoder *encoder;
 124         struct drm_device *dev = crtc->dev;
 125
 126         /*
 127          * We can expect this mutex to be locked if we are not panicking.
 128          * Locking is currently fubar in the panic handler.
 129          */
 130         if (!oops_in_progress)
 131                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 132
 133         drm_for_each_encoder(encoder, dev)
 134                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 135                         return true;
 136         return false;
 137 }
 138 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 139
 140 static void
 141 drm_encoder_disable(struct drm_encoder *encoder)
 142 {
 143         const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 144
 145         if (!encoder_funcs)
 146                 return;
 147
 148         drm_bridge_disable(encoder->bridge);
 149
 150         if (encoder_funcs->disable)
 151                 (*encoder_funcs->disable)(encoder);
 152         else if (encoder_funcs->dpms)
 153                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 154
 155         drm_bridge_post_disable(encoder->bridge);
 156 }
 157
 158 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 159 {
 160         struct drm_encoder *encoder;
 161         struct drm_crtc *crtc;
 162
 163         drm_warn_on_modeset_not_all_locked(dev);
 164
 165         drm_for_each_encoder(encoder, dev) {
 166                 if (!drm_helper_encoder_in_use(encoder)) {
 167                         drm_encoder_disable(encoder);
 168                         /* disconnect encoder from any connector */
 169                         encoder->crtc = NULL;
 170                 }
 171         }
 172
 173         drm_for_each_crtc(crtc, dev) {
 174                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 175                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 176                 if (!crtc->enabled) {
 177                         if (crtc_funcs->disable)
 178                                 (*crtc_funcs->disable)(crtc);
 179                         else
 180                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 181                         crtc->primary->fb = NULL;
 182                 }
 183         }
 184 }
 185
 186 /**
 187  * drm_helper_disable_unused_functions - disable unused objects
 188  * @dev: DRM device
 189  *
 190  * This function walks through the entire mode setting configuration of @dev. It
 191  * will remove any CRTC links of unused encoders and encoder links of
 192  * disconnected connectors. Then it will disable all unused encoders and CRTCs
 193  * either by calling their disable callback if available or by calling their
 194  * dpms callback with DRM_MODE_DPMS_OFF.
 195  *
 196  * NOTE:
 197  *
 198  * This function is part of the legacy modeset helper library and will cause
 199  * major confusion with atomic drivers. This is because atomic helpers guarantee
 200  * to never call ->disable() hooks on a disabled function, or ->enable() hooks
 201  * on an enabled functions. drm_helper_disable_unused_functions() on the other
 202  * hand throws such guarantees into the wind and calls disable hooks
 203  * unconditionally on unused functions.
 204  */
 205 void drm_helper_disable_unused_functions(struct drm_device *dev)
 206 {
 207         if (drm_core_check_feature(dev, DRIVER_ATOMIC))
 208                 DRM_ERROR("Called for atomic driver, this is not what you want.\n");
 209
 210         drm_modeset_lock_all(dev);
 211         __drm_helper_disable_unused_functions(dev);
 212         drm_modeset_unlock_all(dev);
 213 }
 214 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 215
 216 /*
 217  * Check the CRTC we're going to map each output to vs. its current
 218  * CRTC.  If they don't match, we have to disable the output and the CRTC
 219  * since the driver will have to re-route things.
 220  */
 221 static void
 222 drm_crtc_prepare_encoders(struct drm_device *dev)
 223 {
 224         const struct drm_encoder_helper_funcs *encoder_funcs;
 225         struct drm_encoder *encoder;
 226
 227         drm_for_each_encoder(encoder, dev) {
 228                 encoder_funcs = encoder->helper_private;
 229                 if (!encoder_funcs)
 230                         continue;
 231
 232                 /* Disable unused encoders */
 233                 if (encoder->crtc == NULL)
 234                         drm_encoder_disable(encoder);
 235                 /* Disable encoders whose CRTC is about to change */
 236                 if (encoder_funcs->get_crtc &&
 237                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
 238                         drm_encoder_disable(encoder);
 239         }
 240 }
 241
 242 /**
 243  * drm_crtc_helper_set_mode - internal helper to set a mode
 244  * @crtc: CRTC to program
 245  * @mode: mode to use
 246  * @x: horizontal offset into the surface
 247  * @y: vertical offset into the surface
 248  * @old_fb: old framebuffer, for cleanup
 249  *
 250  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 251  * to fixup or reject the mode prior to trying to set it. This is an internal
 252  * helper that drivers could e.g. use to update properties that require the
 253  * entire output pipe to be disabled and re-enabled in a new configuration. For
 254  * example for changing whether audio is enabled on a hdmi link or for changing
 255  * panel fitter or dither attributes. It is also called by the
 256  * drm_crtc_helper_set_config() helper function to drive the mode setting
 257  * sequence.
 258  *
 259  * Returns:
 260  * True if the mode was set successfully, false otherwise.
 261  */
 262 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 263                               struct drm_display_mode *mode,
 264                               int x, int y,
 265                               struct drm_framebuffer *old_fb)
 266 {
 267         struct drm_device *dev = crtc->dev;
 268         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
 269         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 270         const struct drm_encoder_helper_funcs *encoder_funcs;
 271         int saved_x, saved_y;
 272         bool saved_enabled;
 273         struct drm_encoder *encoder;
 274         bool ret = true;
 275
 276         drm_warn_on_modeset_not_all_locked(dev);
 277
 278         saved_enabled = crtc->enabled;
 279         crtc->enabled = drm_helper_crtc_in_use(crtc);
 280         if (!crtc->enabled)
 281                 return true;
 282
 283         adjusted_mode = drm_mode_duplicate(dev, mode);
 284         if (!adjusted_mode) {
 285                 crtc->enabled = saved_enabled;
 286                 return false;
 287         }
 288
 289         saved_mode = crtc->mode;
 290         saved_hwmode = crtc->hwmode;
 291         saved_x = crtc->x;
 292         saved_y = crtc->y;
 293
 294         /* Update crtc values up front so the driver can rely on them for mode
 295          * setting.
 296          */
 297         crtc->mode = *mode;
 298         crtc->x = x;
 299         crtc->y = y;
 300
 301         /* Pass our mode to the connectors and the CRTC to give them a chance to
 302          * adjust it according to limitations or connector properties, and also
 303          * a chance to reject the mode entirely.
 304          */
 305         drm_for_each_encoder(encoder, dev) {
 306
 307                 if (encoder->crtc != crtc)
 308                         continue;
 309
 310                 encoder_funcs = encoder->helper_private;
 311                 if (!encoder_funcs)
 312                         continue;
 313
 314                 ret = drm_bridge_mode_fixup(encoder->bridge,
 315                         mode, adjusted_mode);
 316                 if (!ret) {
 317                         DRM_DEBUG_KMS("Bridge fixup failed\n");
 318                         goto done;
 319                 }
 320
 321                 encoder_funcs = encoder->helper_private;
 322                 if (encoder_funcs->mode_fixup) {
 323                         if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 324                                                               adjusted_mode))) {
 325                                 DRM_DEBUG_KMS("Encoder fixup failed\n");
 326                                 goto done;
 327                         }
 328                 }
 329         }
 330
 331         if (crtc_funcs->mode_fixup) {
 332                 if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
 333                                                 adjusted_mode))) {
 334                         DRM_DEBUG_KMS("CRTC fixup failed\n");
 335                         goto done;
 336                 }
 337         }
 338         DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
 339
 340         crtc->hwmode = *adjusted_mode;
 341
 342         /* Prepare the encoders and CRTCs before setting the mode. */
 343         drm_for_each_encoder(encoder, dev) {
 344
 345                 if (encoder->crtc != crtc)
 346                         continue;
 347
 348                 encoder_funcs = encoder->helper_private;
 349                 if (!encoder_funcs)
 350                         continue;
 351
 352                 drm_bridge_disable(encoder->bridge);
 353
 354                 /* Disable the encoders as the first thing we do. */
 355                 if (encoder_funcs->prepare)
 356                         encoder_funcs->prepare(encoder);
 357
 358                 drm_bridge_post_disable(encoder->bridge);
 359         }
 360
 361         drm_crtc_prepare_encoders(dev);
 362
 363         crtc_funcs->prepare(crtc);
 364
 365         /* Set up the DPLL and any encoders state that needs to adjust or depend
 366          * on the DPLL.
 367          */
 368         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 369         if (!ret)
 370             goto done;
 371
 372         drm_for_each_encoder(encoder, dev) {
 373
 374                 if (encoder->crtc != crtc)
 375                         continue;
 376
 377                 encoder_funcs = encoder->helper_private;
 378                 if (!encoder_funcs)
 379                         continue;
 380
 381                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
 382                         encoder->base.id, encoder->name,
 383                         mode->base.id, mode->name);
 384                 if (encoder_funcs->mode_set)
 385                         encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 386
 387                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
 388         }
 389
 390         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 391         crtc_funcs->commit(crtc);
 392
 393         drm_for_each_encoder(encoder, dev) {
 394
 395                 if (encoder->crtc != crtc)
 396                         continue;
 397
 398                 encoder_funcs = encoder->helper_private;
 399                 if (!encoder_funcs)
 400                         continue;
 401
 402                 drm_bridge_pre_enable(encoder->bridge);
 403
 404                 if (encoder_funcs->commit)
 405                         encoder_funcs->commit(encoder);
 406
 407                 drm_bridge_enable(encoder->bridge);
 408         }
 409
 410         /* Calculate and store various constants which
 411          * are later needed by vblank and swap-completion
 412          * timestamping. They are derived from true hwmode.
 413          */
 414         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 415
 416         /* FIXME: add subpixel order */
 417 done:
 418         drm_mode_destroy(dev, adjusted_mode);
 419         if (!ret) {
 420                 crtc->enabled = saved_enabled;
 421                 crtc->mode = saved_mode;
 422                 crtc->hwmode = saved_hwmode;
 423                 crtc->x = saved_x;
 424                 crtc->y = saved_y;
 425         }
 426
 427         return ret;
 428 }
 429 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 430
 431 static void
 432 drm_crtc_helper_disable(struct drm_crtc *crtc)
 433 {
 434         struct drm_device *dev = crtc->dev;
 435         struct drm_connector *connector;
 436         struct drm_encoder *encoder;
 437
 438         /* Decouple all encoders and their attached connectors from this crtc */
 439         drm_for_each_encoder(encoder, dev) {
 440                 if (encoder->crtc != crtc)
 441                         continue;
 442
 443                 drm_for_each_connector(connector, dev) {
 444                         if (connector->encoder != encoder)
 445                                 continue;
 446
 447                         connector->encoder = NULL;
 448
 449                         /*
 450                          * drm_helper_disable_unused_functions() ought to be
 451                          * doing this, but since we've decoupled the encoder
 452                          * from the connector above, the required connection
 453                          * between them is henceforth no longer available.
 454                          */
 455                         connector->dpms = DRM_MODE_DPMS_OFF;
 456
 457                         /* we keep a reference while the encoder is bound */
 458                         drm_connector_unreference(connector);
 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 **save_encoder_crtcs, *new_crtc;
 507         struct drm_encoder **save_connector_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 *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_encoder_crtcs = kzalloc(dev->mode_config.num_encoder *
 553                                 sizeof(struct drm_crtc *), GFP_KERNEL);
 554         if (!save_encoder_crtcs)
 555                 return -ENOMEM;
 556
 557         save_connector_encoders = kzalloc(dev->mode_config.num_connector *
 558                                 sizeof(struct drm_encoder *), GFP_KERNEL);
 559         if (!save_connector_encoders) {
 560                 kfree(save_encoder_crtcs);
 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_encoder_crtcs[count++] = encoder->crtc;
 572         }
 573
 574         count = 0;
 575         drm_for_each_connector(connector, dev) {
 576                 save_connector_encoders[count++] = connector->encoder;
 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->format != set->crtc->primary->fb->format) {
 593                         mode_changed = true;
 594                 } else
 595                         fb_changed = true;
 596         }
 597
 598         if (set->x != set->crtc->x || set->y != set->crtc->y)
 599                 fb_changed = true;
 600
 601         if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
 602                 DRM_DEBUG_KMS("modes are different, full mode set\n");
 603                 drm_mode_debug_printmodeline(&set->crtc->mode);
 604                 drm_mode_debug_printmodeline(set->mode);
 605                 mode_changed = true;
 606         }
 607
 608         /* take a reference on all unbound connectors in set, reuse the
 609          * already taken reference for bound connectors
 610          */
 611         for (ro = 0; ro < set->num_connectors; ro++) {
 612                 if (set->connectors[ro]->encoder)
 613                         continue;
 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         kfree(save_connector_encoders);
 736         kfree(save_encoder_crtcs);
 737         return 0;
 738
 739 fail:
 740         /* Restore all previous data. */
 741         count = 0;
 742         drm_for_each_encoder(encoder, dev) {
 743                 encoder->crtc = save_encoder_crtcs[count++];
 744         }
 745
 746         count = 0;
 747         drm_for_each_connector(connector, dev) {
 748                 connector->encoder = save_connector_encoders[count++];
 749         }
 750
 751         /* after fail drop reference on all unbound connectors in set, let
 752          * bound connectors keep their reference
 753          */
 754         for (ro = 0; ro < set->num_connectors; ro++) {
 755                 if (set->connectors[ro]->encoder)
 756                         continue;
 757                 drm_connector_unreference(set->connectors[ro]);
 758         }
 759
 760         /* Try to restore the config */
 761         if (mode_changed &&
 762             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 763                                       save_set.y, save_set.fb))
 764                 DRM_ERROR("failed to restore config after modeset failure\n");
 765
 766         kfree(save_connector_encoders);
 767         kfree(save_encoder_crtcs);
 768         return ret;
 769 }
 770 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 771
 772 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 773 {
 774         int dpms = DRM_MODE_DPMS_OFF;
 775         struct drm_connector *connector;
 776         struct drm_device *dev = encoder->dev;
 777
 778         drm_for_each_connector(connector, dev)
 779                 if (connector->encoder == encoder)
 780                         if (connector->dpms < dpms)
 781                                 dpms = connector->dpms;
 782         return dpms;
 783 }
 784
 785 /* Helper which handles bridge ordering around encoder dpms */
 786 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 787 {
 788         struct drm_bridge *bridge = encoder->bridge;
 789         const struct drm_encoder_helper_funcs *encoder_funcs;
 790
 791         encoder_funcs = encoder->helper_private;
 792         if (!encoder_funcs)
 793                 return;
 794
 795         if (mode == DRM_MODE_DPMS_ON)
 796                 drm_bridge_pre_enable(bridge);
 797         else
 798                 drm_bridge_disable(bridge);
 799
 800         if (encoder_funcs->dpms)
 801                 encoder_funcs->dpms(encoder, mode);
 802
 803         if (mode == DRM_MODE_DPMS_ON)
 804                 drm_bridge_enable(bridge);
 805         else
 806                 drm_bridge_post_disable(bridge);
 807 }
 808
 809 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 810 {
 811         int dpms = DRM_MODE_DPMS_OFF;
 812         struct drm_connector *connector;
 813         struct drm_device *dev = crtc->dev;
 814
 815         drm_for_each_connector(connector, dev)
 816                 if (connector->encoder && connector->encoder->crtc == crtc)
 817                         if (connector->dpms < dpms)
 818                                 dpms = connector->dpms;
 819         return dpms;
 820 }
 821
 822 /**
 823  * drm_helper_connector_dpms() - connector dpms helper implementation
 824  * @connector: affected connector
 825  * @mode: DPMS mode
 826  *
 827  * The drm_helper_connector_dpms() helper function implements the ->dpms()
 828  * callback of struct &drm_connector_funcs for drivers using the legacy CRTC helpers.
 829  *
 830  * This is the main helper function provided by the CRTC helper framework for
 831  * implementing the DPMS connector attribute. It computes the new desired DPMS
 832  * state for all encoders and CRTCs in the output mesh and calls the ->dpms()
 833  * callbacks provided by the driver in struct &drm_crtc_helper_funcs and struct
 834  * &drm_encoder_helper_funcs appropriately.
 835  *
 836  * This function is deprecated.  New drivers must implement atomic modeset
 837  * support, for which this function is unsuitable. Instead drivers should use
 838  * drm_atomic_helper_connector_dpms().
 839  *
 840  * Returns:
 841  * Always returns 0.
 842  */
 843 int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 844 {
 845         struct drm_encoder *encoder = connector->encoder;
 846         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 847         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 848
 849         if (mode == connector->dpms)
 850                 return 0;
 851
 852         old_dpms = connector->dpms;
 853         connector->dpms = mode;
 854
 855         if (encoder)
 856                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 857
 858         /* from off to on, do crtc then encoder */
 859         if (mode < old_dpms) {
 860                 if (crtc) {
 861                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 862                         if (crtc_funcs->dpms)
 863                                 (*crtc_funcs->dpms) (crtc,
 864                                                      drm_helper_choose_crtc_dpms(crtc));
 865                 }
 866                 if (encoder)
 867                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 868         }
 869
 870         /* from on to off, do encoder then crtc */
 871         if (mode > old_dpms) {
 872                 if (encoder)
 873                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 874                 if (crtc) {
 875                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 876                         if (crtc_funcs->dpms)
 877                                 (*crtc_funcs->dpms) (crtc,
 878                                                      drm_helper_choose_crtc_dpms(crtc));
 879                 }
 880         }
 881
 882         return 0;
 883 }
 884 EXPORT_SYMBOL(drm_helper_connector_dpms);
 885
 886 /**
 887  * drm_helper_resume_force_mode - force-restore mode setting configuration
 888  * @dev: drm_device which should be restored
 889  *
 890  * Drivers which use the mode setting helpers can use this function to
 891  * force-restore the mode setting configuration e.g. on resume or when something
 892  * else might have trampled over the hw state (like some overzealous old BIOSen
 893  * tended to do).
 894  *
 895  * This helper doesn't provide a error return value since restoring the old
 896  * config should never fail due to resource allocation issues since the driver
 897  * has successfully set the restored configuration already. Hence this should
 898  * boil down to the equivalent of a few dpms on calls, which also don't provide
 899  * an error code.
 900  *
 901  * Drivers where simply restoring an old configuration again might fail (e.g.
 902  * due to slight differences in allocating shared resources when the
 903  * configuration is restored in a different order than when userspace set it up)
 904  * need to use their own restore logic.
 905  *
 906  * This function is deprecated. New drivers should implement atomic mode-
 907  * setting and use the atomic suspend/resume helpers.
 908  *
 909  * See also:
 910  * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 911  */
 912 void drm_helper_resume_force_mode(struct drm_device *dev)
 913 {
 914         struct drm_crtc *crtc;
 915         struct drm_encoder *encoder;
 916         const struct drm_crtc_helper_funcs *crtc_funcs;
 917         int encoder_dpms;
 918         bool ret;
 919
 920         drm_modeset_lock_all(dev);
 921         drm_for_each_crtc(crtc, dev) {
 922
 923                 if (!crtc->enabled)
 924                         continue;
 925
 926                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 927                                                crtc->x, crtc->y, crtc->primary->fb);
 928
 929                 /* Restoring the old config should never fail! */
 930                 if (ret == false)
 931                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 932
 933                 /* Turn off outputs that were already powered off */
 934                 if (drm_helper_choose_crtc_dpms(crtc)) {
 935                         drm_for_each_encoder(encoder, dev) {
 936
 937                                 if(encoder->crtc != crtc)
 938                                         continue;
 939
 940                                 encoder_dpms = drm_helper_choose_encoder_dpms(
 941                                                         encoder);
 942
 943                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
 944                         }
 945
 946                         crtc_funcs = crtc->helper_private;
 947                         if (crtc_funcs->dpms)
 948                                 (*crtc_funcs->dpms) (crtc,
 949                                                      drm_helper_choose_crtc_dpms(crtc));
 950                 }
 951         }
 952
 953         /* disable the unused connectors while restoring the modesetting */
 954         __drm_helper_disable_unused_functions(dev);
 955         drm_modeset_unlock_all(dev);
 956 }
 957 EXPORT_SYMBOL(drm_helper_resume_force_mode);
 958
 959 /**
 960  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
 961  * @crtc: DRM CRTC
 962  * @mode: DRM display mode which userspace requested
 963  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
 964  * @x: x offset of the CRTC scanout area on the underlying framebuffer
 965  * @y: y offset of the CRTC scanout area on the underlying framebuffer
 966  * @old_fb: previous framebuffer
 967  *
 968  * This function implements a callback useable as the ->mode_set callback
 969  * required by the CRTC helpers. Besides the atomic plane helper functions for
 970  * the primary plane the driver must also provide the ->mode_set_nofb callback
 971  * to set up the CRTC.
 972  *
 973  * This is a transitional helper useful for converting drivers to the atomic
 974  * interfaces.
 975  */
 976 int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
 977                              struct drm_display_mode *adjusted_mode, int x, int y,
 978                              struct drm_framebuffer *old_fb)
 979 {
 980         struct drm_crtc_state *crtc_state;
 981         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 982         int ret;
 983
 984         if (crtc->funcs->atomic_duplicate_state)
 985                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
 986         else {
 987                 if (!crtc->state)
 988                         drm_atomic_helper_crtc_reset(crtc);
 989
 990                 crtc_state = drm_atomic_helper_crtc_duplicate_state(crtc);
 991         }
 992
 993         if (!crtc_state)
 994                 return -ENOMEM;
 995
 996         crtc_state->planes_changed = true;
 997         crtc_state->mode_changed = true;
 998         ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
 999         if (ret)
1000                 goto out;
1001         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
1002
1003         if (crtc_funcs->atomic_check) {
1004                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
1005                 if (ret)
1006                         goto out;
1007         }
1008
1009         swap(crtc->state, crtc_state);
1010
1011         crtc_funcs->mode_set_nofb(crtc);
1012
1013         ret = drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
1014
1015 out:
1016         if (crtc_state) {
1017                 if (crtc->funcs->atomic_destroy_state)
1018                         crtc->funcs->atomic_destroy_state(crtc, crtc_state);
1019                 else
1020                         drm_atomic_helper_crtc_destroy_state(crtc, crtc_state);
1021         }
1022
1023         return ret;
1024 }
1025 EXPORT_SYMBOL(drm_helper_crtc_mode_set);
1026
1027 /**
1028  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
1029  * @crtc: DRM CRTC
1030  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1031  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1032  * @old_fb: previous framebuffer
1033  *
1034  * This function implements a callback useable as the ->mode_set_base used
1035  * required by the CRTC helpers. The driver must provide the atomic plane helper
1036  * functions for the primary plane.
1037  *
1038  * This is a transitional helper useful for converting drivers to the atomic
1039  * interfaces.
1040  */
1041 int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
1042                                   struct drm_framebuffer *old_fb)
1043 {
1044         struct drm_plane_state *plane_state;
1045         struct drm_plane *plane = crtc->primary;
1046
1047         if (plane->funcs->atomic_duplicate_state)
1048                 plane_state = plane->funcs->atomic_duplicate_state(plane);
1049         else {
1050                 if (!plane->state)
1051                         drm_atomic_helper_plane_reset(plane);
1052
1053                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
1054         }
1055         if (!plane_state)
1056                 return -ENOMEM;
1057         plane_state->plane = plane;
1058
1059         plane_state->crtc = crtc;
1060         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
1061         plane_state->crtc_x = 0;
1062         plane_state->crtc_y = 0;
1063         plane_state->crtc_h = crtc->mode.vdisplay;
1064         plane_state->crtc_w = crtc->mode.hdisplay;
1065         plane_state->src_x = x << 16;
1066         plane_state->src_y = y << 16;
1067         plane_state->src_h = crtc->mode.vdisplay << 16;
1068         plane_state->src_w = crtc->mode.hdisplay << 16;
1069
1070         return drm_plane_helper_commit(plane, plane_state, old_fb);
1071 }
1072 EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);