sys/dev/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 0
 127         if (!oops_in_progress) {
 128                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 129                 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 130         }
 131 #endif
 132
 133         drm_for_each_connector(connector, dev)
 134                 if (connector->encoder == encoder)
 135                         return true;
 136         return false;
 137 }
 138 EXPORT_SYMBOL(drm_helper_encoder_in_use);
 139
 140 /**
 141  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 142  * @crtc: CRTC to check
 143  *
 144  * Checks whether @crtc is with the current mode setting output configuration
 145  * in use by any connector. This doesn't mean that it is actually enabled since
 146  * the DPMS state is tracked separately.
 147  *
 148  * Returns:
 149  * True if @crtc is used, false otherwise.
 150  */
 151 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 152 {
 153         struct drm_encoder *encoder;
 154         struct drm_device *dev = crtc->dev;
 155
 156         /*
 157          * We can expect this mutex to be locked if we are not panicking.
 158          * Locking is currently fubar in the panic handler.
 159          */
 160 #if 0
 161         if (!oops_in_progress)
 162 #endif
 163                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 164
 165         drm_for_each_encoder(encoder, dev)
 166                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 167                         return true;
 168         return false;
 169 }
 170 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 171
 172 static void
 173 drm_encoder_disable(struct drm_encoder *encoder)
 174 {
 175         const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 176
 177         if (!encoder_funcs)
 178                 return;
 179
 180         drm_bridge_disable(encoder->bridge);
 181
 182         if (encoder_funcs->disable)
 183                 (*encoder_funcs->disable)(encoder);
 184         else if (encoder_funcs->dpms)
 185                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 186
 187         drm_bridge_post_disable(encoder->bridge);
 188 }
 189
 190 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 191 {
 192         struct drm_encoder *encoder;
 193         struct drm_crtc *crtc;
 194
 195         drm_warn_on_modeset_not_all_locked(dev);
 196
 197         drm_for_each_encoder(encoder, dev) {
 198                 if (!drm_helper_encoder_in_use(encoder)) {
 199                         drm_encoder_disable(encoder);
 200                         /* disconnect encoder from any connector */
 201                         encoder->crtc = NULL;
 202                 }
 203         }
 204
 205         drm_for_each_crtc(crtc, dev) {
 206                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 207                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 208                 if (!crtc->enabled) {
 209                         if (crtc_funcs->disable)
 210                                 (*crtc_funcs->disable)(crtc);
 211                         else
 212                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 213                         crtc->primary->fb = NULL;
 214                 }
 215         }
 216 }
 217
 218 /**
 219  * drm_helper_disable_unused_functions - disable unused objects
 220  * @dev: DRM device
 221  *
 222  * This function walks through the entire mode setting configuration of @dev. It
 223  * will remove any CRTC links of unused encoders and encoder links of
 224  * disconnected connectors. Then it will disable all unused encoders and CRTCs
 225  * either by calling their disable callback if available or by calling their
 226  * dpms callback with DRM_MODE_DPMS_OFF.
 227  *
 228  * NOTE:
 229  *
 230  * This function is part of the legacy modeset helper library and will cause
 231  * major confusion with atomic drivers. This is because atomic helpers guarantee
 232  * to never call ->disable() hooks on a disabled function, or ->enable() hooks
 233  * on an enabled functions. drm_helper_disable_unused_functions() on the other
 234  * hand throws such guarantees into the wind and calls disable hooks
 235  * unconditionally on unused functions.
 236  */
 237 void drm_helper_disable_unused_functions(struct drm_device *dev)
 238 {
 239         drm_modeset_lock_all(dev);
 240         __drm_helper_disable_unused_functions(dev);
 241         drm_modeset_unlock_all(dev);
 242 }
 243 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 244
 245 /*
 246  * Check the CRTC we're going to map each output to vs. its current
 247  * CRTC.  If they don't match, we have to disable the output and the CRTC
 248  * since the driver will have to re-route things.
 249  */
 250 static void
 251 drm_crtc_prepare_encoders(struct drm_device *dev)
 252 {
 253         const struct drm_encoder_helper_funcs *encoder_funcs;
 254         struct drm_encoder *encoder;
 255
 256         drm_for_each_encoder(encoder, dev) {
 257                 encoder_funcs = encoder->helper_private;
 258                 if (!encoder_funcs)
 259                         continue;
 260
 261                 /* Disable unused encoders */
 262                 if (encoder->crtc == NULL)
 263                         drm_encoder_disable(encoder);
 264                 /* Disable encoders whose CRTC is about to change */
 265                 if (encoder_funcs->get_crtc &&
 266                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
 267                         drm_encoder_disable(encoder);
 268         }
 269 }
 270
 271 /**
 272  * drm_crtc_helper_set_mode - internal helper to set a mode
 273  * @crtc: CRTC to program
 274  * @mode: mode to use
 275  * @x: horizontal offset into the surface
 276  * @y: vertical offset into the surface
 277  * @old_fb: old framebuffer, for cleanup
 278  *
 279  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 280  * to fixup or reject the mode prior to trying to set it. This is an internal
 281  * helper that drivers could e.g. use to update properties that require the
 282  * entire output pipe to be disabled and re-enabled in a new configuration. For
 283  * example for changing whether audio is enabled on a hdmi link or for changing
 284  * panel fitter or dither attributes. It is also called by the
 285  * drm_crtc_helper_set_config() helper function to drive the mode setting
 286  * sequence.
 287  *
 288  * Returns:
 289  * True if the mode was set successfully, false otherwise.
 290  */
 291 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 292                               struct drm_display_mode *mode,
 293                               int x, int y,
 294                               struct drm_framebuffer *old_fb)
 295 {
 296         struct drm_device *dev = crtc->dev;
 297         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
 298         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 299         const struct drm_encoder_helper_funcs *encoder_funcs;
 300         int saved_x, saved_y;
 301         bool saved_enabled;
 302         struct drm_encoder *encoder;
 303         bool ret = true;
 304
 305         drm_warn_on_modeset_not_all_locked(dev);
 306
 307         saved_enabled = crtc->enabled;
 308         crtc->enabled = drm_helper_crtc_in_use(crtc);
 309         if (!crtc->enabled)
 310                 return true;
 311
 312         adjusted_mode = drm_mode_duplicate(dev, mode);
 313         if (!adjusted_mode) {
 314                 crtc->enabled = saved_enabled;
 315                 return false;
 316         }
 317
 318         saved_mode = crtc->mode;
 319         saved_hwmode = crtc->hwmode;
 320         saved_x = crtc->x;
 321         saved_y = crtc->y;
 322
 323         /* Update crtc values up front so the driver can rely on them for mode
 324          * setting.
 325          */
 326         crtc->mode = *mode;
 327         crtc->x = x;
 328         crtc->y = y;
 329
 330         /* Pass our mode to the connectors and the CRTC to give them a chance to
 331          * adjust it according to limitations or connector properties, and also
 332          * a chance to reject the mode entirely.
 333          */
 334         drm_for_each_encoder(encoder, dev) {
 335
 336                 if (encoder->crtc != crtc)
 337                         continue;
 338
 339                 encoder_funcs = encoder->helper_private;
 340                 if (!encoder_funcs)
 341                         continue;
 342
 343                 ret = drm_bridge_mode_fixup(encoder->bridge,
 344                         mode, adjusted_mode);
 345                 if (!ret) {
 346                         DRM_DEBUG_KMS("Bridge fixup failed\n");
 347                         goto done;
 348                 }
 349
 350                 encoder_funcs = encoder->helper_private;
 351                 if (encoder_funcs->mode_fixup) {
 352                         if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 353                                                               adjusted_mode))) {
 354                                 DRM_DEBUG_KMS("Encoder fixup failed\n");
 355                                 goto done;
 356                         }
 357                 }
 358         }
 359
 360         if (crtc_funcs->mode_fixup) {
 361                 if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
 362                                                 adjusted_mode))) {
 363                         DRM_DEBUG_KMS("CRTC fixup failed\n");
 364                         goto done;
 365                 }
 366         }
 367         DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
 368
 369         crtc->hwmode = *adjusted_mode;
 370
 371         /* Prepare the encoders and CRTCs before setting the mode. */
 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_bridge_disable(encoder->bridge);
 382
 383                 /* Disable the encoders as the first thing we do. */
 384                 if (encoder_funcs->prepare)
 385                         encoder_funcs->prepare(encoder);
 386
 387                 drm_bridge_post_disable(encoder->bridge);
 388         }
 389
 390         drm_crtc_prepare_encoders(dev);
 391
 392         crtc_funcs->prepare(crtc);
 393
 394         /* Set up the DPLL and any encoders state that needs to adjust or depend
 395          * on the DPLL.
 396          */
 397         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 398         if (!ret)
 399             goto done;
 400
 401         drm_for_each_encoder(encoder, dev) {
 402
 403                 if (encoder->crtc != crtc)
 404                         continue;
 405
 406                 encoder_funcs = encoder->helper_private;
 407                 if (!encoder_funcs)
 408                         continue;
 409
 410                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
 411                         encoder->base.id, encoder->name,
 412                         mode->base.id, mode->name);
 413                 if (encoder_funcs->mode_set)
 414                         encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 415
 416                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
 417         }
 418
 419         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 420         crtc_funcs->commit(crtc);
 421
 422         drm_for_each_encoder(encoder, dev) {
 423
 424                 if (encoder->crtc != crtc)
 425                         continue;
 426
 427                 encoder_funcs = encoder->helper_private;
 428                 if (!encoder_funcs)
 429                         continue;
 430
 431                 drm_bridge_pre_enable(encoder->bridge);
 432
 433                 if (encoder_funcs->commit)
 434                         encoder_funcs->commit(encoder);
 435
 436                 drm_bridge_enable(encoder->bridge);
 437         }
 438
 439         /* Calculate and store various constants which
 440          * are later needed by vblank and swap-completion
 441          * timestamping. They are derived from true hwmode.
 442          */
 443         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 444
 445         /* FIXME: add subpixel order */
 446 done:
 447         drm_mode_destroy(dev, adjusted_mode);
 448         if (!ret) {
 449                 crtc->enabled = saved_enabled;
 450                 crtc->mode = saved_mode;
 451                 crtc->hwmode = saved_hwmode;
 452                 crtc->x = saved_x;
 453                 crtc->y = saved_y;
 454         }
 455
 456         return ret;
 457 }
 458 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 459
 460 static void
 461 drm_crtc_helper_disable(struct drm_crtc *crtc)
 462 {
 463         struct drm_device *dev = crtc->dev;
 464         struct drm_connector *connector;
 465         struct drm_encoder *encoder;
 466
 467         /* Decouple all encoders and their attached connectors from this crtc */
 468         drm_for_each_encoder(encoder, dev) {
 469                 if (encoder->crtc != crtc)
 470                         continue;
 471
 472                 drm_for_each_connector(connector, dev) {
 473                         if (connector->encoder != encoder)
 474                                 continue;
 475
 476                         connector->encoder = NULL;
 477
 478                         /*
 479                          * drm_helper_disable_unused_functions() ought to be
 480                          * doing this, but since we've decoupled the encoder
 481                          * from the connector above, the required connection
 482                          * between them is henceforth no longer available.
 483                          */
 484                         connector->dpms = DRM_MODE_DPMS_OFF;
 485
 486                         /* we keep a reference while the encoder is bound */
 487                         drm_connector_unreference(connector);
 488                 }
 489         }
 490
 491         __drm_helper_disable_unused_functions(dev);
 492 }
 493
 494 /**
 495  * drm_crtc_helper_set_config - set a new config from userspace
 496  * @set: mode set configuration
 497  *
 498  * The drm_crtc_helper_set_config() helper function implements the set_config
 499  * callback of struct &drm_crtc_funcs for drivers using the legacy CRTC helpers.
 500  *
 501  * It first tries to locate the best encoder for each connector by calling the
 502  * connector ->best_encoder() (struct &drm_connector_helper_funcs) helper
 503  * operation.
 504  *
 505  * After locating the appropriate encoders, the helper function will call the
 506  * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
 507  * or reject it completely in which case an error will be returned to the
 508  * application. If the new configuration after mode adjustment is identical to
 509  * the current configuration the helper function will return without performing
 510  * any other operation.
 511  *
 512  * If the adjusted mode is identical to the current mode but changes to the
 513  * frame buffer need to be applied, the drm_crtc_helper_set_config() function
 514  * will call the CRTC ->mode_set_base() (struct &drm_crtc_helper_funcs) helper
 515  * operation.
 516  *
 517  * If the adjusted mode differs from the current mode, or if the
 518  * ->mode_set_base() helper operation is not provided, the helper function
 519  * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
 520  * and ->commit() CRTC and encoder helper operations, in that order.
 521  * Alternatively it can also use the dpms and disable helper operations. For
 522  * details see struct &drm_crtc_helper_funcs and struct
 523  * &drm_encoder_helper_funcs.
 524  *
 525  * This function is deprecated.  New drivers must implement atomic modeset
 526  * support, for which this function is unsuitable. Instead drivers should use
 527  * drm_atomic_helper_set_config().
 528  *
 529  * Returns:
 530  * Returns 0 on success, negative errno numbers on failure.
 531  */
 532 int drm_crtc_helper_set_config(struct drm_mode_set *set)
 533 {
 534         struct drm_device *dev;
 535         struct drm_crtc **save_encoder_crtcs, *new_crtc;
 536         struct drm_encoder **save_connector_encoders, *new_encoder, *encoder;
 537         bool mode_changed = false; /* if true do a full mode set */
 538         bool fb_changed = false; /* if true and !mode_changed just do a flip */
 539         struct drm_connector *connector;
 540         int count = 0, ro, fail = 0;
 541         const struct drm_crtc_helper_funcs *crtc_funcs;
 542         struct drm_mode_set save_set;
 543         int ret;
 544         int i;
 545
 546         DRM_DEBUG_KMS("\n");
 547
 548         BUG_ON(!set);
 549         BUG_ON(!set->crtc);
 550         BUG_ON(!set->crtc->helper_private);
 551
 552         /* Enforce sane interface api - has been abused by the fb helper. */
 553         BUG_ON(!set->mode && set->fb);
 554         BUG_ON(set->fb && set->num_connectors == 0);
 555
 556         crtc_funcs = set->crtc->helper_private;
 557
 558         if (!set->mode)
 559                 set->fb = NULL;
 560
 561         if (set->fb) {
 562                 DRM_DEBUG_KMS("[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 563                               set->crtc->base.id, set->crtc->name,
 564                               set->fb->base.id,
 565                               (int)set->num_connectors, set->x, set->y);
 566         } else {
 567                 DRM_DEBUG_KMS("[CRTC:%d:%s] [NOFB]\n",
 568                               set->crtc->base.id, set->crtc->name);
 569                 drm_crtc_helper_disable(set->crtc);
 570                 return 0;
 571         }
 572
 573         dev = set->crtc->dev;
 574
 575         drm_warn_on_modeset_not_all_locked(dev);
 576
 577         /*
 578          * Allocate space for the backup of all (non-pointer) encoder and
 579          * connector data.
 580          */
 581         save_encoder_crtcs = kzalloc(dev->mode_config.num_encoder *
 582                                 sizeof(struct drm_crtc *), GFP_KERNEL);
 583         if (!save_encoder_crtcs)
 584                 return -ENOMEM;
 585
 586         save_connector_encoders = kzalloc(dev->mode_config.num_connector *
 587                                 sizeof(struct drm_encoder *), GFP_KERNEL);
 588         if (!save_connector_encoders) {
 589                 kfree(save_encoder_crtcs);
 590                 return -ENOMEM;
 591         }
 592
 593         /*
 594          * Copy data. Note that driver private data is not affected.
 595          * Should anything bad happen only the expected state is
 596          * restored, not the drivers personal bookkeeping.
 597          */
 598         count = 0;
 599         drm_for_each_encoder(encoder, dev) {
 600                 save_encoder_crtcs[count++] = encoder->crtc;
 601         }
 602
 603         count = 0;
 604         drm_for_each_connector(connector, dev) {
 605                 save_connector_encoders[count++] = connector->encoder;
 606         }
 607
 608         save_set.crtc = set->crtc;
 609         save_set.mode = &set->crtc->mode;
 610         save_set.x = set->crtc->x;
 611         save_set.y = set->crtc->y;
 612         save_set.fb = set->crtc->primary->fb;
 613
 614         /* We should be able to check here if the fb has the same properties
 615          * and then just flip_or_move it */
 616         if (set->crtc->primary->fb != set->fb) {
 617                 /* If we have no fb then treat it as a full mode set */
 618                 if (set->crtc->primary->fb == NULL) {
 619                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 620                         mode_changed = true;
 621                 } else if (set->fb->pixel_format !=
 622                            set->crtc->primary->fb->pixel_format) {
 623                         mode_changed = true;
 624                 } else
 625                         fb_changed = true;
 626         }
 627
 628         if (set->x != set->crtc->x || set->y != set->crtc->y)
 629                 fb_changed = true;
 630
 631         if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
 632                 DRM_DEBUG_KMS("modes are different, full mode set\n");
 633                 drm_mode_debug_printmodeline(&set->crtc->mode);
 634                 drm_mode_debug_printmodeline(set->mode);
 635                 mode_changed = true;
 636         }
 637
 638         /* take a reference on all unbound connectors in set, reuse the
 639          * already taken reference for bound connectors
 640          */
 641         for (ro = 0; ro < set->num_connectors; ro++) {
 642                 if (set->connectors[ro]->encoder)
 643                         continue;
 644                 drm_connector_reference(set->connectors[ro]);
 645         }
 646
 647         /* a) traverse passed in connector list and get encoders for them */
 648         count = 0;
 649         drm_for_each_connector(connector, dev) {
 650                 const struct drm_connector_helper_funcs *connector_funcs =
 651                         connector->helper_private;
 652                 new_encoder = connector->encoder;
 653                 for (ro = 0; ro < set->num_connectors; ro++) {
 654                         if (set->connectors[ro] == connector) {
 655                                 new_encoder = connector_funcs->best_encoder(connector);
 656                                 /* if we can't get an encoder for a connector
 657                                    we are setting now - then fail */
 658                                 if (new_encoder == NULL)
 659                                         /* don't break so fail path works correct */
 660                                         fail = 1;
 661
 662                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
 663                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 664                                         mode_changed = true;
 665                                 }
 666
 667                                 break;
 668                         }
 669                 }
 670
 671                 if (new_encoder != connector->encoder) {
 672                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 673                         mode_changed = true;
 674                         /* If the encoder is reused for another connector, then
 675                          * the appropriate crtc will be set later.
 676                          */
 677                         if (connector->encoder)
 678                                 connector->encoder->crtc = NULL;
 679                         connector->encoder = new_encoder;
 680                 }
 681         }
 682
 683         if (fail) {
 684                 ret = -EINVAL;
 685                 goto fail;
 686         }
 687
 688         count = 0;
 689         drm_for_each_connector(connector, dev) {
 690                 if (!connector->encoder)
 691                         continue;
 692
 693                 if (connector->encoder->crtc == set->crtc)
 694                         new_crtc = NULL;
 695                 else
 696                         new_crtc = connector->encoder->crtc;
 697
 698                 for (ro = 0; ro < set->num_connectors; ro++) {
 699                         if (set->connectors[ro] == connector)
 700                                 new_crtc = set->crtc;
 701                 }
 702
 703                 /* Make sure the new CRTC will work with the encoder */
 704                 if (new_crtc &&
 705                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 706                         ret = -EINVAL;
 707                         goto fail;
 708                 }
 709                 if (new_crtc != connector->encoder->crtc) {
 710                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 711                         mode_changed = true;
 712                         connector->encoder->crtc = new_crtc;
 713                 }
 714                 if (new_crtc) {
 715                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
 716                                       connector->base.id, connector->name,
 717                                       new_crtc->base.id, new_crtc->name);
 718                 } else {
 719                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 720                                       connector->base.id, connector->name);
 721                 }
 722         }
 723
 724         /* mode_set_base is not a required function */
 725         if (fb_changed && !crtc_funcs->mode_set_base)
 726                 mode_changed = true;
 727
 728         if (mode_changed) {
 729                 if (drm_helper_crtc_in_use(set->crtc)) {
 730                         DRM_DEBUG_KMS("attempting to set mode from"
 731                                         " userspace\n");
 732                         drm_mode_debug_printmodeline(set->mode);
 733                         set->crtc->primary->fb = set->fb;
 734                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 735                                                       set->x, set->y,
 736                                                       save_set.fb)) {
 737                                 DRM_ERROR("failed to set mode on [CRTC:%d:%s]\n",
 738                                           set->crtc->base.id, set->crtc->name);
 739                                 set->crtc->primary->fb = save_set.fb;
 740                                 ret = -EINVAL;
 741                                 goto fail;
 742                         }
 743                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 744                         for (i = 0; i < set->num_connectors; i++) {
 745                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 746                                               set->connectors[i]->name);
 747                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 748                         }
 749                 }
 750                 __drm_helper_disable_unused_functions(dev);
 751         } else if (fb_changed) {
 752                 set->crtc->x = set->x;
 753                 set->crtc->y = set->y;
 754                 set->crtc->primary->fb = set->fb;
 755                 ret = crtc_funcs->mode_set_base(set->crtc,
 756                                                 set->x, set->y, save_set.fb);
 757                 if (ret != 0) {
 758                         set->crtc->x = save_set.x;
 759                         set->crtc->y = save_set.y;
 760                         set->crtc->primary->fb = save_set.fb;
 761                         goto fail;
 762                 }
 763         }
 764
 765         kfree(save_connector_encoders);
 766         kfree(save_encoder_crtcs);
 767         return 0;
 768
 769 fail:
 770         /* Restore all previous data. */
 771         count = 0;
 772         drm_for_each_encoder(encoder, dev) {
 773                 encoder->crtc = save_encoder_crtcs[count++];
 774         }
 775
 776         count = 0;
 777         drm_for_each_connector(connector, dev) {
 778                 connector->encoder = save_connector_encoders[count++];
 779         }
 780
 781         /* after fail drop reference on all unbound connectors in set, let
 782          * bound connectors keep their reference
 783          */
 784         for (ro = 0; ro < set->num_connectors; ro++) {
 785                 if (set->connectors[ro]->encoder)
 786                         continue;
 787                 drm_connector_unreference(set->connectors[ro]);
 788         }
 789
 790         /* Try to restore the config */
 791         if (mode_changed &&
 792             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 793                                       save_set.y, save_set.fb))
 794                 DRM_ERROR("failed to restore config after modeset failure\n");
 795
 796         kfree(save_connector_encoders);
 797         kfree(save_encoder_crtcs);
 798         return ret;
 799 }
 800 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 801
 802 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 803 {
 804         int dpms = DRM_MODE_DPMS_OFF;
 805         struct drm_connector *connector;
 806         struct drm_device *dev = encoder->dev;
 807
 808         drm_for_each_connector(connector, dev)
 809                 if (connector->encoder == encoder)
 810                         if (connector->dpms < dpms)
 811                                 dpms = connector->dpms;
 812         return dpms;
 813 }
 814
 815 /* Helper which handles bridge ordering around encoder dpms */
 816 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 817 {
 818         struct drm_bridge *bridge = encoder->bridge;
 819         const struct drm_encoder_helper_funcs *encoder_funcs;
 820
 821         encoder_funcs = encoder->helper_private;
 822         if (!encoder_funcs)
 823                 return;
 824
 825         if (mode == DRM_MODE_DPMS_ON)
 826                 drm_bridge_pre_enable(bridge);
 827         else
 828                 drm_bridge_disable(bridge);
 829
 830         if (encoder_funcs->dpms)
 831                 encoder_funcs->dpms(encoder, mode);
 832
 833         if (mode == DRM_MODE_DPMS_ON)
 834                 drm_bridge_enable(bridge);
 835         else
 836                 drm_bridge_post_disable(bridge);
 837 }
 838
 839 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 840 {
 841         int dpms = DRM_MODE_DPMS_OFF;
 842         struct drm_connector *connector;
 843         struct drm_device *dev = crtc->dev;
 844
 845         drm_for_each_connector(connector, dev)
 846                 if (connector->encoder && connector->encoder->crtc == crtc)
 847                         if (connector->dpms < dpms)
 848                                 dpms = connector->dpms;
 849         return dpms;
 850 }
 851
 852 /**
 853  * drm_helper_connector_dpms() - connector dpms helper implementation
 854  * @connector: affected connector
 855  * @mode: DPMS mode
 856  *
 857  * The drm_helper_connector_dpms() helper function implements the ->dpms()
 858  * callback of struct &drm_connector_funcs for drivers using the legacy CRTC helpers.
 859  *
 860  * This is the main helper function provided by the CRTC helper framework for
 861  * implementing the DPMS connector attribute. It computes the new desired DPMS
 862  * state for all encoders and CRTCs in the output mesh and calls the ->dpms()
 863  * callbacks provided by the driver in struct &drm_crtc_helper_funcs and struct
 864  * &drm_encoder_helper_funcs appropriately.
 865  *
 866  * This function is deprecated.  New drivers must implement atomic modeset
 867  * support, for which this function is unsuitable. Instead drivers should use
 868  * drm_atomic_helper_connector_dpms().
 869  *
 870  * Returns:
 871  * Always returns 0.
 872  */
 873 int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 874 {
 875         struct drm_encoder *encoder = connector->encoder;
 876         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 877         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 878
 879         if (mode == connector->dpms)
 880                 return 0;
 881
 882         old_dpms = connector->dpms;
 883         connector->dpms = mode;
 884
 885         if (encoder)
 886                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 887
 888         /* from off to on, do crtc then encoder */
 889         if (mode < old_dpms) {
 890                 if (crtc) {
 891                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 892                         if (crtc_funcs->dpms)
 893                                 (*crtc_funcs->dpms) (crtc,
 894                                                      drm_helper_choose_crtc_dpms(crtc));
 895                 }
 896                 if (encoder)
 897                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 898         }
 899
 900         /* from on to off, do encoder then crtc */
 901         if (mode > old_dpms) {
 902                 if (encoder)
 903                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 904                 if (crtc) {
 905                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 906                         if (crtc_funcs->dpms)
 907                                 (*crtc_funcs->dpms) (crtc,
 908                                                      drm_helper_choose_crtc_dpms(crtc));
 909                 }
 910         }
 911
 912         return 0;
 913 }
 914 EXPORT_SYMBOL(drm_helper_connector_dpms);
 915
 916 /**
 917  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
 918  * @fb: drm_framebuffer object to fill out
 919  * @mode_cmd: metadata from the userspace fb creation request
 920  *
 921  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
 922  * metadata fields.
 923  */
 924 void drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
 925                                     const struct drm_mode_fb_cmd2 *mode_cmd)
 926 {
 927         int i;
 928
 929         fb->width = mode_cmd->width;
 930         fb->height = mode_cmd->height;
 931         for (i = 0; i < 4; i++) {
 932                 fb->pitches[i] = mode_cmd->pitches[i];
 933                 fb->offsets[i] = mode_cmd->offsets[i];
 934                 fb->modifier[i] = mode_cmd->modifier[i];
 935         }
 936         drm_fb_get_bpp_depth(mode_cmd->pixel_format, &fb->depth,
 937                                     &fb->bits_per_pixel);
 938         fb->pixel_format = mode_cmd->pixel_format;
 939         fb->flags = mode_cmd->flags;
 940 }
 941 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
 942
 943 /**
 944  * drm_helper_resume_force_mode - force-restore mode setting configuration
 945  * @dev: drm_device which should be restored
 946  *
 947  * Drivers which use the mode setting helpers can use this function to
 948  * force-restore the mode setting configuration e.g. on resume or when something
 949  * else might have trampled over the hw state (like some overzealous old BIOSen
 950  * tended to do).
 951  *
 952  * This helper doesn't provide a error return value since restoring the old
 953  * config should never fail due to resource allocation issues since the driver
 954  * has successfully set the restored configuration already. Hence this should
 955  * boil down to the equivalent of a few dpms on calls, which also don't provide
 956  * an error code.
 957  *
 958  * Drivers where simply restoring an old configuration again might fail (e.g.
 959  * due to slight differences in allocating shared resources when the
 960  * configuration is restored in a different order than when userspace set it up)
 961  * need to use their own restore logic.
 962  *
 963  * This function is deprecated. New drivers should implement atomic mode-
 964  * setting and use the atomic suspend/resume helpers.
 965  *
 966  * See also:
 967  * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 968  */
 969 void drm_helper_resume_force_mode(struct drm_device *dev)
 970 {
 971         struct drm_crtc *crtc;
 972         struct drm_encoder *encoder;
 973         const struct drm_crtc_helper_funcs *crtc_funcs;
 974         int encoder_dpms;
 975         bool ret;
 976
 977         drm_modeset_lock_all(dev);
 978         drm_for_each_crtc(crtc, dev) {
 979
 980                 if (!crtc->enabled)
 981                         continue;
 982
 983                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 984                                                crtc->x, crtc->y, crtc->primary->fb);
 985
 986                 /* Restoring the old config should never fail! */
 987                 if (ret == false)
 988                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 989
 990                 /* Turn off outputs that were already powered off */
 991                 if (drm_helper_choose_crtc_dpms(crtc)) {
 992                         drm_for_each_encoder(encoder, dev) {
 993
 994                                 if(encoder->crtc != crtc)
 995                                         continue;
 996
 997                                 encoder_dpms = drm_helper_choose_encoder_dpms(
 998                                                         encoder);
 999
1000                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
1001                         }
1002
1003                         crtc_funcs = crtc->helper_private;
1004                         if (crtc_funcs->dpms)
1005                                 (*crtc_funcs->dpms) (crtc,
1006                                                      drm_helper_choose_crtc_dpms(crtc));
1007                 }
1008         }
1009
1010         /* disable the unused connectors while restoring the modesetting */
1011         __drm_helper_disable_unused_functions(dev);
1012         drm_modeset_unlock_all(dev);
1013 }
1014 EXPORT_SYMBOL(drm_helper_resume_force_mode);
1015
1016 /**
1017  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
1018  * @crtc: DRM CRTC
1019  * @mode: DRM display mode which userspace requested
1020  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
1021  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1022  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1023  * @old_fb: previous framebuffer
1024  *
1025  * This function implements a callback useable as the ->mode_set callback
1026  * required by the CRTC helpers. Besides the atomic plane helper functions for
1027  * the primary plane the driver must also provide the ->mode_set_nofb callback
1028  * to set up the CRTC.
1029  *
1030  * This is a transitional helper useful for converting drivers to the atomic
1031  * interfaces.
1032  */
1033 int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
1034                              struct drm_display_mode *adjusted_mode, int x, int y,
1035                              struct drm_framebuffer *old_fb)
1036 {
1037         struct drm_crtc_state *crtc_state;
1038         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
1039         int ret;
1040
1041         if (crtc->funcs->atomic_duplicate_state)
1042                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
1043         else {
1044                 if (!crtc->state)
1045                         drm_atomic_helper_crtc_reset(crtc);
1046
1047                 crtc_state = drm_atomic_helper_crtc_duplicate_state(crtc);
1048         }
1049
1050         if (!crtc_state)
1051                 return -ENOMEM;
1052
1053         crtc_state->planes_changed = true;
1054         crtc_state->mode_changed = true;
1055         ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
1056         if (ret)
1057                 goto out;
1058         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
1059
1060         if (crtc_funcs->atomic_check) {
1061                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
1062                 if (ret)
1063                         goto out;
1064         }
1065
1066         swap(crtc->state, crtc_state);
1067
1068         crtc_funcs->mode_set_nofb(crtc);
1069
1070         ret = drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
1071
1072 out:
1073         if (crtc_state) {
1074                 if (crtc->funcs->atomic_destroy_state)
1075                         crtc->funcs->atomic_destroy_state(crtc, crtc_state);
1076                 else
1077                         drm_atomic_helper_crtc_destroy_state(crtc, crtc_state);
1078         }
1079
1080         return ret;
1081 }
1082 EXPORT_SYMBOL(drm_helper_crtc_mode_set);
1083
1084 /**
1085  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
1086  * @crtc: DRM CRTC
1087  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1088  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1089  * @old_fb: previous framebuffer
1090  *
1091  * This function implements a callback useable as the ->mode_set_base used
1092  * required by the CRTC helpers. The driver must provide the atomic plane helper
1093  * functions for the primary plane.
1094  *
1095  * This is a transitional helper useful for converting drivers to the atomic
1096  * interfaces.
1097  */
1098 int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
1099                                   struct drm_framebuffer *old_fb)
1100 {
1101         struct drm_plane_state *plane_state;
1102         struct drm_plane *plane = crtc->primary;
1103
1104         if (plane->funcs->atomic_duplicate_state)
1105                 plane_state = plane->funcs->atomic_duplicate_state(plane);
1106         else {
1107                 if (!plane->state)
1108                         drm_atomic_helper_plane_reset(plane);
1109
1110                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
1111         }
1112         if (!plane_state)
1113                 return -ENOMEM;
1114         plane_state->plane = plane;
1115
1116         plane_state->crtc = crtc;
1117         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
1118         plane_state->crtc_x = 0;
1119         plane_state->crtc_y = 0;
1120         plane_state->crtc_h = crtc->mode.vdisplay;
1121         plane_state->crtc_w = crtc->mode.hdisplay;
1122         plane_state->src_x = x << 16;
1123         plane_state->src_y = y << 16;
1124         plane_state->src_h = crtc->mode.vdisplay << 16;
1125         plane_state->src_w = crtc->mode.hdisplay << 16;
1126
1127         return drm_plane_helper_commit(plane, plane_state, old_fb);
1128 }
1129 EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);
1130
1131 /**
1132  * drm_helper_crtc_enable_color_mgmt - enable color management properties
1133  * @crtc: DRM CRTC
1134  * @degamma_lut_size: the size of the degamma lut (before CSC)
1135  * @gamma_lut_size: the size of the gamma lut (after CSC)
1136  *
1137  * This function lets the driver enable the color correction properties on a
1138  * CRTC. This includes 3 degamma, csc and gamma properties that userspace can
1139  * set and 2 size properties to inform the userspace of the lut sizes.
1140  */
1141 void drm_helper_crtc_enable_color_mgmt(struct drm_crtc *crtc,
1142                                        int degamma_lut_size,
1143                                        int gamma_lut_size)
1144 {
1145         struct drm_device *dev = crtc->dev;
1146         struct drm_mode_config *config = &dev->mode_config;
1147
1148         drm_object_attach_property(&crtc->base,
1149                                    config->degamma_lut_property, 0);
1150         drm_object_attach_property(&crtc->base,
1151                                    config->ctm_property, 0);
1152         drm_object_attach_property(&crtc->base,
1153                                    config->gamma_lut_property, 0);
1154
1155         drm_object_attach_property(&crtc->base,
1156                                    config->degamma_lut_size_property,
1157                                    degamma_lut_size);
1158         drm_object_attach_property(&crtc->base,
1159                                    config->gamma_lut_size_property,
1160                                    gamma_lut_size);
1161 }
1162 EXPORT_SYMBOL(drm_helper_crtc_enable_color_mgmt);