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/export.h>
  33 #include <linux/kernel.h>
  34 #include <linux/moduleparam.h>
  35
  36 #include <drm/drm_atomic.h>
  37 #include <drm/drm_atomic_helper.h>
  38 #include <drm/drm_atomic_uapi.h>
  39 #include <drm/drm_bridge.h>
  40 #include <drm/drm_crtc.h>
  41 #include <drm/drm_crtc_helper.h>
  42 #include <drm/drm_drv.h>
  43 #include <drm/drm_edid.h>
  44 #include <drm/drm_encoder.h>
  45 #include <drm/drm_fb_helper.h>
  46 #include <drm/drm_fourcc.h>
  47 #include <drm/drm_plane_helper.h>
  48 #include <drm/drm_print.h>
  49 #include <drm/drm_vblank.h>
  50
  51 /**
  52  * DOC: overview
  53  *
  54  * The CRTC modeset helper library provides a default set_config implementation
  55  * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
  56  * the same callbacks which drivers can use to e.g. restore the modeset
  57  * configuration on resume with drm_helper_resume_force_mode().
  58  *
  59  * Note that this helper library doesn't track the current power state of CRTCs
  60  * and encoders. It can call callbacks like &drm_encoder_helper_funcs.dpms even
  61  * though the hardware is already in the desired state. This deficiency has been
  62  * fixed in the atomic helpers.
  63  *
  64  * The driver callbacks are mostly compatible with the atomic modeset helpers,
  65  * except for the handling of the primary plane: Atomic helpers require that the
  66  * primary plane is implemented as a real standalone plane and not directly tied
  67  * to the CRTC state. For easier transition this library provides functions to
  68  * implement the old semantics required by the CRTC helpers using the new plane
  69  * and atomic helper callbacks.
  70  *
  71  * Drivers are strongly urged to convert to the atomic helpers (by way of first
  72  * converting to the plane helpers). New drivers must not use these functions
  73  * but need to implement the atomic interface instead, potentially using the
  74  * atomic helpers for that.
  75  *
  76  * These legacy modeset helpers use the same function table structures as
  77  * all other modesetting helpers. See the documentation for struct
  78  * &drm_crtc_helper_funcs, &struct drm_encoder_helper_funcs and struct
  79  * &drm_connector_helper_funcs.
  80  */
  81
  82 /**
  83  * drm_helper_encoder_in_use - check if a given encoder is in use
  84  * @encoder: encoder to check
  85  *
  86  * Checks whether @encoder is with the current mode setting output configuration
  87  * in use by any connector. This doesn't mean that it is actually enabled since
  88  * the DPMS state is tracked separately.
  89  *
  90  * Returns:
  91  * True if @encoder is used, false otherwise.
  92  */
  93 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
  94 {
  95         struct drm_connector *connector;
  96         struct drm_connector_list_iter conn_iter;
  97         struct drm_device *dev = encoder->dev;
  98
  99         WARN_ON(drm_drv_uses_atomic_modeset(dev));
 100
 101         /*
 102          * We can expect this mutex to be locked if we are not panicking.
 103          * Locking is currently fubar in the panic handler.
 104          */
 105         if (!oops_in_progress) {
 106                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 107                 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 108         }
 109
 110
 111         drm_connector_list_iter_begin(dev, &conn_iter);
 112         drm_for_each_connector_iter(connector, &conn_iter) {
 113                 if (connector->encoder == encoder) {
 114                         drm_connector_list_iter_end(&conn_iter);
 115                         return true;
 116                 }
 117         }
 118         drm_connector_list_iter_end(&conn_iter);
 119         return false;
 120 }
 121 EXPORT_SYMBOL(drm_helper_encoder_in_use);
 122
 123 /**
 124  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 125  * @crtc: CRTC to check
 126  *
 127  * Checks whether @crtc is with the current mode setting output configuration
 128  * in use by any connector. This doesn't mean that it is actually enabled since
 129  * the DPMS state is tracked separately.
 130  *
 131  * Returns:
 132  * True if @crtc is used, false otherwise.
 133  */
 134 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 135 {
 136         struct drm_encoder *encoder;
 137         struct drm_device *dev = crtc->dev;
 138
 139         WARN_ON(drm_drv_uses_atomic_modeset(dev));
 140
 141         /*
 142          * We can expect this mutex to be locked if we are not panicking.
 143          * Locking is currently fubar in the panic handler.
 144          */
 145         if (!oops_in_progress)
 146                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 147
 148         drm_for_each_encoder(encoder, dev)
 149                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 150                         return true;
 151         return false;
 152 }
 153 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 154
 155 static void
 156 drm_encoder_disable(struct drm_encoder *encoder)
 157 {
 158         const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 159
 160         if (!encoder_funcs)
 161                 return;
 162
 163         drm_bridge_disable(encoder->bridge);
 164
 165         if (encoder_funcs->disable)
 166                 (*encoder_funcs->disable)(encoder);
 167         else if (encoder_funcs->dpms)
 168                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 169
 170         drm_bridge_post_disable(encoder->bridge);
 171 }
 172
 173 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 174 {
 175         struct drm_encoder *encoder;
 176         struct drm_crtc *crtc;
 177
 178         drm_warn_on_modeset_not_all_locked(dev);
 179
 180         drm_for_each_encoder(encoder, dev) {
 181                 if (!drm_helper_encoder_in_use(encoder)) {
 182                         drm_encoder_disable(encoder);
 183                         /* disconnect encoder from any connector */
 184                         encoder->crtc = NULL;
 185                 }
 186         }
 187
 188         drm_for_each_crtc(crtc, dev) {
 189                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 190                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 191                 if (!crtc->enabled) {
 192                         if (crtc_funcs->disable)
 193                                 (*crtc_funcs->disable)(crtc);
 194                         else
 195                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 196                         crtc->primary->fb = NULL;
 197                 }
 198         }
 199 }
 200
 201 /**
 202  * drm_helper_disable_unused_functions - disable unused objects
 203  * @dev: DRM device
 204  *
 205  * This function walks through the entire mode setting configuration of @dev. It
 206  * will remove any CRTC links of unused encoders and encoder links of
 207  * disconnected connectors. Then it will disable all unused encoders and CRTCs
 208  * either by calling their disable callback if available or by calling their
 209  * dpms callback with DRM_MODE_DPMS_OFF.
 210  *
 211  * NOTE:
 212  *
 213  * This function is part of the legacy modeset helper library and will cause
 214  * major confusion with atomic drivers. This is because atomic helpers guarantee
 215  * to never call ->disable() hooks on a disabled function, or ->enable() hooks
 216  * on an enabled functions. drm_helper_disable_unused_functions() on the other
 217  * hand throws such guarantees into the wind and calls disable hooks
 218  * unconditionally on unused functions.
 219  */
 220 void drm_helper_disable_unused_functions(struct drm_device *dev)
 221 {
 222         WARN_ON(drm_drv_uses_atomic_modeset(dev));
 223
 224         drm_modeset_lock_all(dev);
 225         __drm_helper_disable_unused_functions(dev);
 226         drm_modeset_unlock_all(dev);
 227 }
 228 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 229
 230 /*
 231  * Check the CRTC we're going to map each output to vs. its current
 232  * CRTC.  If they don't match, we have to disable the output and the CRTC
 233  * since the driver will have to re-route things.
 234  */
 235 static void
 236 drm_crtc_prepare_encoders(struct drm_device *dev)
 237 {
 238         const struct drm_encoder_helper_funcs *encoder_funcs;
 239         struct drm_encoder *encoder;
 240
 241         drm_for_each_encoder(encoder, dev) {
 242                 encoder_funcs = encoder->helper_private;
 243                 if (!encoder_funcs)
 244                         continue;
 245
 246                 /* Disable unused encoders */
 247                 if (encoder->crtc == NULL)
 248                         drm_encoder_disable(encoder);
 249                 /* Disable encoders whose CRTC is about to change */
 250                 if (encoder_funcs->get_crtc &&
 251                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
 252                         drm_encoder_disable(encoder);
 253         }
 254 }
 255
 256 /**
 257  * drm_crtc_helper_set_mode - internal helper to set a mode
 258  * @crtc: CRTC to program
 259  * @mode: mode to use
 260  * @x: horizontal offset into the surface
 261  * @y: vertical offset into the surface
 262  * @old_fb: old framebuffer, for cleanup
 263  *
 264  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 265  * to fixup or reject the mode prior to trying to set it. This is an internal
 266  * helper that drivers could e.g. use to update properties that require the
 267  * entire output pipe to be disabled and re-enabled in a new configuration. For
 268  * example for changing whether audio is enabled on a hdmi link or for changing
 269  * panel fitter or dither attributes. It is also called by the
 270  * drm_crtc_helper_set_config() helper function to drive the mode setting
 271  * sequence.
 272  *
 273  * Returns:
 274  * True if the mode was set successfully, false otherwise.
 275  */
 276 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 277                               struct drm_display_mode *mode,
 278                               int x, int y,
 279                               struct drm_framebuffer *old_fb)
 280 {
 281         struct drm_device *dev = crtc->dev;
 282         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
 283         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 284         const struct drm_encoder_helper_funcs *encoder_funcs;
 285         int saved_x, saved_y;
 286         bool saved_enabled;
 287         struct drm_encoder *encoder;
 288         bool ret = true;
 289
 290         WARN_ON(drm_drv_uses_atomic_modeset(dev));
 291
 292         drm_warn_on_modeset_not_all_locked(dev);
 293
 294         saved_enabled = crtc->enabled;
 295         crtc->enabled = drm_helper_crtc_in_use(crtc);
 296         if (!crtc->enabled)
 297                 return true;
 298
 299         adjusted_mode = drm_mode_duplicate(dev, mode);
 300         if (!adjusted_mode) {
 301                 crtc->enabled = saved_enabled;
 302                 return false;
 303         }
 304
 305         saved_mode = crtc->mode;
 306         saved_hwmode = crtc->hwmode;
 307         saved_x = crtc->x;
 308         saved_y = crtc->y;
 309
 310         /* Update crtc values up front so the driver can rely on them for mode
 311          * setting.
 312          */
 313         crtc->mode = *mode;
 314         crtc->x = x;
 315         crtc->y = y;
 316
 317         /* Pass our mode to the connectors and the CRTC to give them a chance to
 318          * adjust it according to limitations or connector properties, and also
 319          * a chance to reject the mode entirely.
 320          */
 321         drm_for_each_encoder(encoder, dev) {
 322
 323                 if (encoder->crtc != crtc)
 324                         continue;
 325
 326                 encoder_funcs = encoder->helper_private;
 327                 if (!encoder_funcs)
 328                         continue;
 329
 330                 ret = drm_bridge_mode_fixup(encoder->bridge,
 331                         mode, adjusted_mode);
 332                 if (!ret) {
 333                         DRM_DEBUG_KMS("Bridge fixup failed\n");
 334                         goto done;
 335                 }
 336
 337                 encoder_funcs = encoder->helper_private;
 338                 if (encoder_funcs->mode_fixup) {
 339                         if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
 340                                                               adjusted_mode))) {
 341                                 DRM_DEBUG_KMS("Encoder fixup failed\n");
 342                                 goto done;
 343                         }
 344                 }
 345         }
 346
 347         if (crtc_funcs->mode_fixup) {
 348                 if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
 349                                                 adjusted_mode))) {
 350                         DRM_DEBUG_KMS("CRTC fixup failed\n");
 351                         goto done;
 352                 }
 353         }
 354         DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
 355
 356         crtc->hwmode = *adjusted_mode;
 357
 358         /* Prepare the encoders and CRTCs before setting the mode. */
 359         drm_for_each_encoder(encoder, dev) {
 360
 361                 if (encoder->crtc != crtc)
 362                         continue;
 363
 364                 encoder_funcs = encoder->helper_private;
 365                 if (!encoder_funcs)
 366                         continue;
 367
 368                 drm_bridge_disable(encoder->bridge);
 369
 370                 /* Disable the encoders as the first thing we do. */
 371                 if (encoder_funcs->prepare)
 372                         encoder_funcs->prepare(encoder);
 373
 374                 drm_bridge_post_disable(encoder->bridge);
 375         }
 376
 377         drm_crtc_prepare_encoders(dev);
 378
 379         crtc_funcs->prepare(crtc);
 380
 381         /* Set up the DPLL and any encoders state that needs to adjust or depend
 382          * on the DPLL.
 383          */
 384         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 385         if (!ret)
 386             goto done;
 387
 388         drm_for_each_encoder(encoder, dev) {
 389
 390                 if (encoder->crtc != crtc)
 391                         continue;
 392
 393                 encoder_funcs = encoder->helper_private;
 394                 if (!encoder_funcs)
 395                         continue;
 396
 397                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%s]\n",
 398                         encoder->base.id, encoder->name, mode->name);
 399                 if (encoder_funcs->mode_set)
 400                         encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 401
 402                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
 403         }
 404
 405         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 406         crtc_funcs->commit(crtc);
 407
 408         drm_for_each_encoder(encoder, dev) {
 409
 410                 if (encoder->crtc != crtc)
 411                         continue;
 412
 413                 encoder_funcs = encoder->helper_private;
 414                 if (!encoder_funcs)
 415                         continue;
 416
 417                 drm_bridge_pre_enable(encoder->bridge);
 418
 419                 if (encoder_funcs->commit)
 420                         encoder_funcs->commit(encoder);
 421
 422                 drm_bridge_enable(encoder->bridge);
 423         }
 424
 425         /* Calculate and store various constants which
 426          * are later needed by vblank and swap-completion
 427          * timestamping. They are derived from true hwmode.
 428          */
 429         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 430
 431         /* FIXME: add subpixel order */
 432 done:
 433         drm_mode_destroy(dev, adjusted_mode);
 434         if (!ret) {
 435                 crtc->enabled = saved_enabled;
 436                 crtc->mode = saved_mode;
 437                 crtc->hwmode = saved_hwmode;
 438                 crtc->x = saved_x;
 439                 crtc->y = saved_y;
 440         }
 441
 442         return ret;
 443 }
 444 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 445
 446 static void
 447 drm_crtc_helper_disable(struct drm_crtc *crtc)
 448 {
 449         struct drm_device *dev = crtc->dev;
 450         struct drm_connector *connector;
 451         struct drm_encoder *encoder;
 452
 453         /* Decouple all encoders and their attached connectors from this crtc */
 454         drm_for_each_encoder(encoder, dev) {
 455                 struct drm_connector_list_iter conn_iter;
 456
 457                 if (encoder->crtc != crtc)
 458                         continue;
 459
 460                 drm_connector_list_iter_begin(dev, &conn_iter);
 461                 drm_for_each_connector_iter(connector, &conn_iter) {
 462                         if (connector->encoder != encoder)
 463                                 continue;
 464
 465                         connector->encoder = NULL;
 466
 467                         /*
 468                          * drm_helper_disable_unused_functions() ought to be
 469                          * doing this, but since we've decoupled the encoder
 470                          * from the connector above, the required connection
 471                          * between them is henceforth no longer available.
 472                          */
 473                         connector->dpms = DRM_MODE_DPMS_OFF;
 474
 475                         /* we keep a reference while the encoder is bound */
 476                         drm_connector_put(connector);
 477                 }
 478                 drm_connector_list_iter_end(&conn_iter);
 479         }
 480
 481         __drm_helper_disable_unused_functions(dev);
 482 }
 483
 484 /*
 485  * For connectors that support multiple encoders, either the
 486  * .atomic_best_encoder() or .best_encoder() operation must be implemented.
 487  */
 488 struct drm_encoder *
 489 drm_connector_get_single_encoder(struct drm_connector *connector)
 490 {
 491         WARN_ON(connector->encoder_ids[1]);
 492         return drm_encoder_find(connector->dev, NULL, connector->encoder_ids[0]);
 493 }
 494
 495 /**
 496  * drm_crtc_helper_set_config - set a new config from userspace
 497  * @set: mode set configuration
 498  * @ctx: lock acquire context, not used here
 499  *
 500  * The drm_crtc_helper_set_config() helper function implements the of
 501  * &drm_crtc_funcs.set_config callback for drivers using the legacy CRTC
 502  * helpers.
 503  *
 504  * It first tries to locate the best encoder for each connector by calling the
 505  * connector @drm_connector_helper_funcs.best_encoder helper operation.
 506  *
 507  * After locating the appropriate encoders, the helper function will call the
 508  * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
 509  * or reject it completely in which case an error will be returned to the
 510  * application. If the new configuration after mode adjustment is identical to
 511  * the current configuration the helper function will return without performing
 512  * any other operation.
 513  *
 514  * If the adjusted mode is identical to the current mode but changes to the
 515  * frame buffer need to be applied, the drm_crtc_helper_set_config() function
 516  * will call the CRTC &drm_crtc_helper_funcs.mode_set_base helper operation.
 517  *
 518  * If the adjusted mode differs from the current mode, or if the
 519  * ->mode_set_base() helper operation is not provided, the helper function
 520  * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
 521  * and ->commit() CRTC and encoder helper operations, in that order.
 522  * Alternatively it can also use the dpms and disable helper operations. For
 523  * details see &struct drm_crtc_helper_funcs and struct
 524  * &drm_encoder_helper_funcs.
 525  *
 526  * This function is deprecated.  New drivers must implement atomic modeset
 527  * support, for which this function is unsuitable. Instead drivers should use
 528  * drm_atomic_helper_set_config().
 529  *
 530  * Returns:
 531  * Returns 0 on success, negative errno numbers on failure.
 532  */
 533 int drm_crtc_helper_set_config(struct drm_mode_set *set,
 534                                struct drm_modeset_acquire_ctx *ctx)
 535 {
 536         struct drm_device *dev;
 537         struct drm_crtc **save_encoder_crtcs, *new_crtc;
 538         struct drm_encoder **save_connector_encoders, *new_encoder, *encoder;
 539         bool mode_changed = false; /* if true do a full mode set */
 540         bool fb_changed = false; /* if true and !mode_changed just do a flip */
 541         struct drm_connector *connector;
 542         struct drm_connector_list_iter conn_iter;
 543         int count = 0, ro, fail = 0;
 544         const struct drm_crtc_helper_funcs *crtc_funcs;
 545         struct drm_mode_set save_set;
 546         int ret;
 547         int i;
 548
 549         DRM_DEBUG_KMS("\n");
 550
 551         BUG_ON(!set);
 552         BUG_ON(!set->crtc);
 553         BUG_ON(!set->crtc->helper_private);
 554
 555         /* Enforce sane interface api - has been abused by the fb helper. */
 556         BUG_ON(!set->mode && set->fb);
 557         BUG_ON(set->fb && set->num_connectors == 0);
 558
 559         crtc_funcs = set->crtc->helper_private;
 560
 561         dev = set->crtc->dev;
 562         WARN_ON(drm_drv_uses_atomic_modeset(dev));
 563
 564         if (!set->mode)
 565                 set->fb = NULL;
 566
 567         if (set->fb) {
 568                 DRM_DEBUG_KMS("[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 569                               set->crtc->base.id, set->crtc->name,
 570                               set->fb->base.id,
 571                               (int)set->num_connectors, set->x, set->y);
 572         } else {
 573                 DRM_DEBUG_KMS("[CRTC:%d:%s] [NOFB]\n",
 574                               set->crtc->base.id, set->crtc->name);
 575                 drm_crtc_helper_disable(set->crtc);
 576                 return 0;
 577         }
 578
 579         drm_warn_on_modeset_not_all_locked(dev);
 580
 581         /*
 582          * Allocate space for the backup of all (non-pointer) encoder and
 583          * connector data.
 584          */
 585         save_encoder_crtcs = kcalloc(dev->mode_config.num_encoder,
 586                                 sizeof(struct drm_crtc *), GFP_KERNEL);
 587         if (!save_encoder_crtcs)
 588                 return -ENOMEM;
 589
 590         save_connector_encoders = kcalloc(dev->mode_config.num_connector,
 591                                 sizeof(struct drm_encoder *), GFP_KERNEL);
 592         if (!save_connector_encoders) {
 593                 kfree(save_encoder_crtcs);
 594                 return -ENOMEM;
 595         }
 596
 597         /*
 598          * Copy data. Note that driver private data is not affected.
 599          * Should anything bad happen only the expected state is
 600          * restored, not the drivers personal bookkeeping.
 601          */
 602         count = 0;
 603         drm_for_each_encoder(encoder, dev) {
 604                 save_encoder_crtcs[count++] = encoder->crtc;
 605         }
 606
 607         count = 0;
 608         drm_connector_list_iter_begin(dev, &conn_iter);
 609         drm_for_each_connector_iter(connector, &conn_iter)
 610                 save_connector_encoders[count++] = connector->encoder;
 611         drm_connector_list_iter_end(&conn_iter);
 612
 613         save_set.crtc = set->crtc;
 614         save_set.mode = &set->crtc->mode;
 615         save_set.x = set->crtc->x;
 616         save_set.y = set->crtc->y;
 617         save_set.fb = set->crtc->primary->fb;
 618
 619         /* We should be able to check here if the fb has the same properties
 620          * and then just flip_or_move it */
 621         if (set->crtc->primary->fb != set->fb) {
 622                 /* If we have no fb then treat it as a full mode set */
 623                 if (set->crtc->primary->fb == NULL) {
 624                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
 625                         mode_changed = true;
 626                 } else if (set->fb->format != set->crtc->primary->fb->format) {
 627                         mode_changed = true;
 628                 } else
 629                         fb_changed = true;
 630         }
 631
 632         if (set->x != set->crtc->x || set->y != set->crtc->y)
 633                 fb_changed = true;
 634
 635         if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
 636                 DRM_DEBUG_KMS("modes are different, full mode set\n");
 637                 drm_mode_debug_printmodeline(&set->crtc->mode);
 638                 drm_mode_debug_printmodeline(set->mode);
 639                 mode_changed = true;
 640         }
 641
 642         /* take a reference on all unbound connectors in set, reuse the
 643          * already taken reference for bound connectors
 644          */
 645         for (ro = 0; ro < set->num_connectors; ro++) {
 646                 if (set->connectors[ro]->encoder)
 647                         continue;
 648                 drm_connector_get(set->connectors[ro]);
 649         }
 650
 651         /* a) traverse passed in connector list and get encoders for them */
 652         count = 0;
 653         drm_connector_list_iter_begin(dev, &conn_iter);
 654         drm_for_each_connector_iter(connector, &conn_iter) {
 655                 const struct drm_connector_helper_funcs *connector_funcs =
 656                         connector->helper_private;
 657                 new_encoder = connector->encoder;
 658                 for (ro = 0; ro < set->num_connectors; ro++) {
 659                         if (set->connectors[ro] == connector) {
 660                                 if (connector_funcs->best_encoder)
 661                                         new_encoder = connector_funcs->best_encoder(connector);
 662                                 else
 663                                         new_encoder = drm_connector_get_single_encoder(connector);
 664
 665                                 /* if we can't get an encoder for a connector
 666                                    we are setting now - then fail */
 667                                 if (new_encoder == NULL)
 668                                         /* don't break so fail path works correct */
 669                                         fail = 1;
 670
 671                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
 672                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
 673                                         mode_changed = true;
 674                                 }
 675
 676                                 break;
 677                         }
 678                 }
 679
 680                 if (new_encoder != connector->encoder) {
 681                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
 682                         mode_changed = true;
 683                         /* If the encoder is reused for another connector, then
 684                          * the appropriate crtc will be set later.
 685                          */
 686                         if (connector->encoder)
 687                                 connector->encoder->crtc = NULL;
 688                         connector->encoder = new_encoder;
 689                 }
 690         }
 691         drm_connector_list_iter_end(&conn_iter);
 692
 693         if (fail) {
 694                 ret = -EINVAL;
 695                 goto fail;
 696         }
 697
 698         count = 0;
 699         drm_connector_list_iter_begin(dev, &conn_iter);
 700         drm_for_each_connector_iter(connector, &conn_iter) {
 701                 if (!connector->encoder)
 702                         continue;
 703
 704                 if (connector->encoder->crtc == set->crtc)
 705                         new_crtc = NULL;
 706                 else
 707                         new_crtc = connector->encoder->crtc;
 708
 709                 for (ro = 0; ro < set->num_connectors; ro++) {
 710                         if (set->connectors[ro] == connector)
 711                                 new_crtc = set->crtc;
 712                 }
 713
 714                 /* Make sure the new CRTC will work with the encoder */
 715                 if (new_crtc &&
 716                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 717                         ret = -EINVAL;
 718                         drm_connector_list_iter_end(&conn_iter);
 719                         goto fail;
 720                 }
 721                 if (new_crtc != connector->encoder->crtc) {
 722                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
 723                         mode_changed = true;
 724                         connector->encoder->crtc = new_crtc;
 725                 }
 726                 if (new_crtc) {
 727                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
 728                                       connector->base.id, connector->name,
 729                                       new_crtc->base.id, new_crtc->name);
 730                 } else {
 731                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
 732                                       connector->base.id, connector->name);
 733                 }
 734         }
 735         drm_connector_list_iter_end(&conn_iter);
 736
 737         /* mode_set_base is not a required function */
 738         if (fb_changed && !crtc_funcs->mode_set_base)
 739                 mode_changed = true;
 740
 741         if (mode_changed) {
 742                 if (drm_helper_crtc_in_use(set->crtc)) {
 743                         DRM_DEBUG_KMS("attempting to set mode from"
 744                                         " userspace\n");
 745                         drm_mode_debug_printmodeline(set->mode);
 746                         set->crtc->primary->fb = set->fb;
 747                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 748                                                       set->x, set->y,
 749                                                       save_set.fb)) {
 750                                 DRM_ERROR("failed to set mode on [CRTC:%d:%s]\n",
 751                                           set->crtc->base.id, set->crtc->name);
 752                                 set->crtc->primary->fb = save_set.fb;
 753                                 ret = -EINVAL;
 754                                 goto fail;
 755                         }
 756                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
 757                         for (i = 0; i < set->num_connectors; i++) {
 758                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 759                                               set->connectors[i]->name);
 760                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 761                         }
 762                 }
 763                 __drm_helper_disable_unused_functions(dev);
 764         } else if (fb_changed) {
 765                 set->crtc->x = set->x;
 766                 set->crtc->y = set->y;
 767                 set->crtc->primary->fb = set->fb;
 768                 ret = crtc_funcs->mode_set_base(set->crtc,
 769                                                 set->x, set->y, save_set.fb);
 770                 if (ret != 0) {
 771                         set->crtc->x = save_set.x;
 772                         set->crtc->y = save_set.y;
 773                         set->crtc->primary->fb = save_set.fb;
 774                         goto fail;
 775                 }
 776         }
 777
 778         kfree(save_connector_encoders);
 779         kfree(save_encoder_crtcs);
 780         return 0;
 781
 782 fail:
 783         /* Restore all previous data. */
 784         count = 0;
 785         drm_for_each_encoder(encoder, dev) {
 786                 encoder->crtc = save_encoder_crtcs[count++];
 787         }
 788
 789         count = 0;
 790         drm_connector_list_iter_begin(dev, &conn_iter);
 791         drm_for_each_connector_iter(connector, &conn_iter)
 792                 connector->encoder = save_connector_encoders[count++];
 793         drm_connector_list_iter_end(&conn_iter);
 794
 795         /* after fail drop reference on all unbound connectors in set, let
 796          * bound connectors keep their reference
 797          */
 798         for (ro = 0; ro < set->num_connectors; ro++) {
 799                 if (set->connectors[ro]->encoder)
 800                         continue;
 801                 drm_connector_put(set->connectors[ro]);
 802         }
 803
 804         /* Try to restore the config */
 805         if (mode_changed &&
 806             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 807                                       save_set.y, save_set.fb))
 808                 DRM_ERROR("failed to restore config after modeset failure\n");
 809
 810         kfree(save_connector_encoders);
 811         kfree(save_encoder_crtcs);
 812         return ret;
 813 }
 814 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 815
 816 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 817 {
 818         int dpms = DRM_MODE_DPMS_OFF;
 819         struct drm_connector *connector;
 820         struct drm_connector_list_iter conn_iter;
 821         struct drm_device *dev = encoder->dev;
 822
 823         drm_connector_list_iter_begin(dev, &conn_iter);
 824         drm_for_each_connector_iter(connector, &conn_iter)
 825                 if (connector->encoder == encoder)
 826                         if (connector->dpms < dpms)
 827                                 dpms = connector->dpms;
 828         drm_connector_list_iter_end(&conn_iter);
 829
 830         return dpms;
 831 }
 832
 833 /* Helper which handles bridge ordering around encoder dpms */
 834 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 835 {
 836         struct drm_bridge *bridge = encoder->bridge;
 837         const struct drm_encoder_helper_funcs *encoder_funcs;
 838
 839         encoder_funcs = encoder->helper_private;
 840         if (!encoder_funcs)
 841                 return;
 842
 843         if (mode == DRM_MODE_DPMS_ON)
 844                 drm_bridge_pre_enable(bridge);
 845         else
 846                 drm_bridge_disable(bridge);
 847
 848         if (encoder_funcs->dpms)
 849                 encoder_funcs->dpms(encoder, mode);
 850
 851         if (mode == DRM_MODE_DPMS_ON)
 852                 drm_bridge_enable(bridge);
 853         else
 854                 drm_bridge_post_disable(bridge);
 855 }
 856
 857 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 858 {
 859         int dpms = DRM_MODE_DPMS_OFF;
 860         struct drm_connector *connector;
 861         struct drm_connector_list_iter conn_iter;
 862         struct drm_device *dev = crtc->dev;
 863
 864         drm_connector_list_iter_begin(dev, &conn_iter);
 865         drm_for_each_connector_iter(connector, &conn_iter)
 866                 if (connector->encoder && connector->encoder->crtc == crtc)
 867                         if (connector->dpms < dpms)
 868                                 dpms = connector->dpms;
 869         drm_connector_list_iter_end(&conn_iter);
 870
 871         return dpms;
 872 }
 873
 874 /**
 875  * drm_helper_connector_dpms() - connector dpms helper implementation
 876  * @connector: affected connector
 877  * @mode: DPMS mode
 878  *
 879  * The drm_helper_connector_dpms() helper function implements the
 880  * &drm_connector_funcs.dpms callback for drivers using the legacy CRTC
 881  * helpers.
 882  *
 883  * This is the main helper function provided by the CRTC helper framework for
 884  * implementing the DPMS connector attribute. It computes the new desired DPMS
 885  * state for all encoders and CRTCs in the output mesh and calls the
 886  * &drm_crtc_helper_funcs.dpms and &drm_encoder_helper_funcs.dpms callbacks
 887  * provided by the driver.
 888  *
 889  * This function is deprecated.  New drivers must implement atomic modeset
 890  * support, where DPMS is handled in the DRM core.
 891  *
 892  * Returns:
 893  * Always returns 0.
 894  */
 895 int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 896 {
 897         struct drm_encoder *encoder = connector->encoder;
 898         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 899         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 900
 901         WARN_ON(drm_drv_uses_atomic_modeset(connector->dev));
 902
 903         if (mode == connector->dpms)
 904                 return 0;
 905
 906         old_dpms = connector->dpms;
 907         connector->dpms = mode;
 908
 909         if (encoder)
 910                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 911
 912         /* from off to on, do crtc then encoder */
 913         if (mode < old_dpms) {
 914                 if (crtc) {
 915                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 916                         if (crtc_funcs->dpms)
 917                                 (*crtc_funcs->dpms) (crtc,
 918                                                      drm_helper_choose_crtc_dpms(crtc));
 919                 }
 920                 if (encoder)
 921                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 922         }
 923
 924         /* from on to off, do encoder then crtc */
 925         if (mode > old_dpms) {
 926                 if (encoder)
 927                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 928                 if (crtc) {
 929                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 930                         if (crtc_funcs->dpms)
 931                                 (*crtc_funcs->dpms) (crtc,
 932                                                      drm_helper_choose_crtc_dpms(crtc));
 933                 }
 934         }
 935
 936         return 0;
 937 }
 938 EXPORT_SYMBOL(drm_helper_connector_dpms);
 939
 940 /**
 941  * drm_helper_resume_force_mode - force-restore mode setting configuration
 942  * @dev: drm_device which should be restored
 943  *
 944  * Drivers which use the mode setting helpers can use this function to
 945  * force-restore the mode setting configuration e.g. on resume or when something
 946  * else might have trampled over the hw state (like some overzealous old BIOSen
 947  * tended to do).
 948  *
 949  * This helper doesn't provide a error return value since restoring the old
 950  * config should never fail due to resource allocation issues since the driver
 951  * has successfully set the restored configuration already. Hence this should
 952  * boil down to the equivalent of a few dpms on calls, which also don't provide
 953  * an error code.
 954  *
 955  * Drivers where simply restoring an old configuration again might fail (e.g.
 956  * due to slight differences in allocating shared resources when the
 957  * configuration is restored in a different order than when userspace set it up)
 958  * need to use their own restore logic.
 959  *
 960  * This function is deprecated. New drivers should implement atomic mode-
 961  * setting and use the atomic suspend/resume helpers.
 962  *
 963  * See also:
 964  * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 965  */
 966 void drm_helper_resume_force_mode(struct drm_device *dev)
 967 {
 968         struct drm_crtc *crtc;
 969         struct drm_encoder *encoder;
 970         const struct drm_crtc_helper_funcs *crtc_funcs;
 971         int encoder_dpms;
 972         bool ret;
 973
 974         WARN_ON(drm_drv_uses_atomic_modeset(dev));
 975
 976         drm_modeset_lock_all(dev);
 977         drm_for_each_crtc(crtc, dev) {
 978
 979                 if (!crtc->enabled)
 980                         continue;
 981
 982                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
 983                                                crtc->x, crtc->y, crtc->primary->fb);
 984
 985                 /* Restoring the old config should never fail! */
 986                 if (ret == false)
 987                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
 988
 989                 /* Turn off outputs that were already powered off */
 990                 if (drm_helper_choose_crtc_dpms(crtc)) {
 991                         drm_for_each_encoder(encoder, dev) {
 992
 993                                 if(encoder->crtc != crtc)
 994                                         continue;
 995
 996                                 encoder_dpms = drm_helper_choose_encoder_dpms(
 997                                                         encoder);
 998
 999                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
1000                         }
1001
1002                         crtc_funcs = crtc->helper_private;
1003                         if (crtc_funcs->dpms)
1004                                 (*crtc_funcs->dpms) (crtc,
1005                                                      drm_helper_choose_crtc_dpms(crtc));
1006                 }
1007         }
1008
1009         /* disable the unused connectors while restoring the modesetting */
1010         __drm_helper_disable_unused_functions(dev);
1011         drm_modeset_unlock_all(dev);
1012 }
1013 EXPORT_SYMBOL(drm_helper_resume_force_mode);
1014
1015 /**
1016  * drm_helper_force_disable_all - Forcibly turn off all enabled CRTCs
1017  * @dev: DRM device whose CRTCs to turn off
1018  *
1019  * Drivers may want to call this on unload to ensure that all displays are
1020  * unlit and the GPU is in a consistent, low power state. Takes modeset locks.
1021  *
1022  * Note: This should only be used by non-atomic legacy drivers. For an atomic
1023  * version look at drm_atomic_helper_shutdown().
1024  *
1025  * Returns:
1026  * Zero on success, error code on failure.
1027  */
1028 int drm_helper_force_disable_all(struct drm_device *dev)
1029 {
1030         struct drm_crtc *crtc;
1031         int ret = 0;
1032
1033         drm_modeset_lock_all(dev);
1034         drm_for_each_crtc(crtc, dev)
1035                 if (crtc->enabled) {
1036                         struct drm_mode_set set = {
1037                                 .crtc = crtc,
1038                         };
1039
1040                         ret = drm_mode_set_config_internal(&set);
1041                         if (ret)
1042                                 goto out;
1043                 }
1044 out:
1045         drm_modeset_unlock_all(dev);
1046         return ret;
1047 }
1048 EXPORT_SYMBOL(drm_helper_force_disable_all);