drivers/gpu/drm/drm_crtc_helper.c

   1 /*
   2  * Copyright (c) 2006-2008 Intel Corporation
   3  * Copyright (c) 2007 Dave Airlie <[email protected]>
   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 <[email protected]>
  28  *      Dave Airlie <[email protected]>
  29  *      Jesse Barnes <[email protected]>
  30  */
  31
  32 #include <linux/export.h>
  33 #include <linux/kernel.h>
  34 #include <linux/moduleparam.h>
  35 #include <linux/dynamic_debug.h>
  36
  37 #include <drm/drm_atomic.h>
  38 #include <drm/drm_atomic_helper.h>
  39 #include <drm/drm_atomic_uapi.h>
  40 #include <drm/drm_bridge.h>
  41 #include <drm/drm_crtc.h>
  42 #include <drm/drm_crtc_helper.h>
  43 #include <drm/drm_drv.h>
  44 #include <drm/drm_edid.h>
  45 #include <drm/drm_encoder.h>
  46 #include <drm/drm_fourcc.h>
  47 #include <drm/drm_framebuffer.h>
  48 #include <drm/drm_print.h>
  49 #include <drm/drm_vblank.h>
  50
  51 #include "drm_crtc_helper_internal.h"
  52
  53 DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
  54                         "DRM_UT_CORE",
  55                         "DRM_UT_DRIVER",
  56                         "DRM_UT_KMS",
  57                         "DRM_UT_PRIME",
  58                         "DRM_UT_ATOMIC",
  59                         "DRM_UT_VBL",
  60                         "DRM_UT_STATE",
  61                         "DRM_UT_LEASE",
  62                         "DRM_UT_DP",
  63                         "DRM_UT_DRMRES");
  64
  65 /**
  66  * DOC: overview
  67  *
  68  * The CRTC modeset helper library provides a default set_config implementation
  69  * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
  70  * the same callbacks which drivers can use to e.g. restore the modeset
  71  * configuration on resume with drm_helper_resume_force_mode().
  72  *
  73  * Note that this helper library doesn't track the current power state of CRTCs
  74  * and encoders. It can call callbacks like &drm_encoder_helper_funcs.dpms even
  75  * though the hardware is already in the desired state. This deficiency has been
  76  * fixed in the atomic helpers.
  77  *
  78  * The driver callbacks are mostly compatible with the atomic modeset helpers,
  79  * except for the handling of the primary plane: Atomic helpers require that the
  80  * primary plane is implemented as a real standalone plane and not directly tied
  81  * to the CRTC state. For easier transition this library provides functions to
  82  * implement the old semantics required by the CRTC helpers using the new plane
  83  * and atomic helper callbacks.
  84  *
  85  * Drivers are strongly urged to convert to the atomic helpers (by way of first
  86  * converting to the plane helpers). New drivers must not use these functions
  87  * but need to implement the atomic interface instead, potentially using the
  88  * atomic helpers for that.
  89  *
  90  * These legacy modeset helpers use the same function table structures as
  91  * all other modesetting helpers. See the documentation for struct
  92  * &drm_crtc_helper_funcs, &struct drm_encoder_helper_funcs and struct
  93  * &drm_connector_helper_funcs.
  94  */
  95
  96 /**
  97  * drm_helper_encoder_in_use - check if a given encoder is in use
  98  * @encoder: encoder to check
  99  *
 100  * Checks whether @encoder is with the current mode setting output configuration
 101  * in use by any connector. This doesn't mean that it is actually enabled since
 102  * the DPMS state is tracked separately.
 103  *
 104  * Returns:
 105  * True if @encoder is used, false otherwise.
 106  */
 107 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
 108 {
 109         struct drm_connector *connector;
 110         struct drm_connector_list_iter conn_iter;
 111         struct drm_device *dev = encoder->dev;
 112
 113         drm_WARN_ON(dev, drm_drv_uses_atomic_modeset(dev));
 114
 115         /*
 116          * We can expect this mutex to be locked if we are not panicking.
 117          * Locking is currently fubar in the panic handler.
 118          */
 119         if (!oops_in_progress) {
 120                 drm_WARN_ON(dev, !mutex_is_locked(&dev->mode_config.mutex));
 121                 drm_WARN_ON(dev, !drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 122         }
 123
 124
 125         drm_connector_list_iter_begin(dev, &conn_iter);
 126         drm_for_each_connector_iter(connector, &conn_iter) {
 127                 if (connector->encoder == encoder) {
 128                         drm_connector_list_iter_end(&conn_iter);
 129                         return true;
 130                 }
 131         }
 132         drm_connector_list_iter_end(&conn_iter);
 133         return false;
 134 }
 135 EXPORT_SYMBOL(drm_helper_encoder_in_use);
 136
 137 /**
 138  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
 139  * @crtc: CRTC to check
 140  *
 141  * Checks whether @crtc is with the current mode setting output configuration
 142  * in use by any connector. This doesn't mean that it is actually enabled since
 143  * the DPMS state is tracked separately.
 144  *
 145  * Returns:
 146  * True if @crtc is used, false otherwise.
 147  */
 148 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
 149 {
 150         struct drm_encoder *encoder;
 151         struct drm_device *dev = crtc->dev;
 152
 153         drm_WARN_ON(dev, drm_drv_uses_atomic_modeset(dev));
 154
 155         /*
 156          * We can expect this mutex to be locked if we are not panicking.
 157          * Locking is currently fubar in the panic handler.
 158          */
 159         if (!oops_in_progress)
 160                 drm_WARN_ON(dev, !mutex_is_locked(&dev->mode_config.mutex));
 161
 162         drm_for_each_encoder(encoder, dev)
 163                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
 164                         return true;
 165         return false;
 166 }
 167 EXPORT_SYMBOL(drm_helper_crtc_in_use);
 168
 169 static void
 170 drm_encoder_disable(struct drm_encoder *encoder)
 171 {
 172         const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
 173
 174         if (!encoder_funcs)
 175                 return;
 176
 177         if (encoder_funcs->disable)
 178                 (*encoder_funcs->disable)(encoder);
 179         else if (encoder_funcs->dpms)
 180                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
 181 }
 182
 183 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
 184 {
 185         struct drm_encoder *encoder;
 186         struct drm_crtc *crtc;
 187
 188         drm_warn_on_modeset_not_all_locked(dev);
 189
 190         drm_for_each_encoder(encoder, dev) {
 191                 if (!drm_helper_encoder_in_use(encoder)) {
 192                         drm_encoder_disable(encoder);
 193                         /* disconnect encoder from any connector */
 194                         encoder->crtc = NULL;
 195                 }
 196         }
 197
 198         drm_for_each_crtc(crtc, dev) {
 199                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 200
 201                 crtc->enabled = drm_helper_crtc_in_use(crtc);
 202                 if (!crtc->enabled) {
 203                         if (crtc_funcs->disable)
 204                                 (*crtc_funcs->disable)(crtc);
 205                         else
 206                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
 207                         crtc->primary->fb = NULL;
 208                 }
 209         }
 210 }
 211
 212 /**
 213  * drm_helper_disable_unused_functions - disable unused objects
 214  * @dev: DRM device
 215  *
 216  * This function walks through the entire mode setting configuration of @dev. It
 217  * will remove any CRTC links of unused encoders and encoder links of
 218  * disconnected connectors. Then it will disable all unused encoders and CRTCs
 219  * either by calling their disable callback if available or by calling their
 220  * dpms callback with DRM_MODE_DPMS_OFF.
 221  *
 222  * NOTE:
 223  *
 224  * This function is part of the legacy modeset helper library and will cause
 225  * major confusion with atomic drivers. This is because atomic helpers guarantee
 226  * to never call ->disable() hooks on a disabled function, or ->enable() hooks
 227  * on an enabled functions. drm_helper_disable_unused_functions() on the other
 228  * hand throws such guarantees into the wind and calls disable hooks
 229  * unconditionally on unused functions.
 230  */
 231 void drm_helper_disable_unused_functions(struct drm_device *dev)
 232 {
 233         drm_WARN_ON(dev, drm_drv_uses_atomic_modeset(dev));
 234
 235         drm_modeset_lock_all(dev);
 236         __drm_helper_disable_unused_functions(dev);
 237         drm_modeset_unlock_all(dev);
 238 }
 239 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
 240
 241 /*
 242  * Check the CRTC we're going to map each output to vs. its current
 243  * CRTC.  If they don't match, we have to disable the output and the CRTC
 244  * since the driver will have to re-route things.
 245  */
 246 static void
 247 drm_crtc_prepare_encoders(struct drm_device *dev)
 248 {
 249         const struct drm_encoder_helper_funcs *encoder_funcs;
 250         struct drm_encoder *encoder;
 251
 252         drm_for_each_encoder(encoder, dev) {
 253                 encoder_funcs = encoder->helper_private;
 254                 if (!encoder_funcs)
 255                         continue;
 256
 257                 /* Disable unused encoders */
 258                 if (encoder->crtc == NULL)
 259                         drm_encoder_disable(encoder);
 260         }
 261 }
 262
 263 /**
 264  * drm_crtc_helper_set_mode - internal helper to set a mode
 265  * @crtc: CRTC to program
 266  * @mode: mode to use
 267  * @x: horizontal offset into the surface
 268  * @y: vertical offset into the surface
 269  * @old_fb: old framebuffer, for cleanup
 270  *
 271  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
 272  * to fixup or reject the mode prior to trying to set it. This is an internal
 273  * helper that drivers could e.g. use to update properties that require the
 274  * entire output pipe to be disabled and re-enabled in a new configuration. For
 275  * example for changing whether audio is enabled on a hdmi link or for changing
 276  * panel fitter or dither attributes. It is also called by the
 277  * drm_crtc_helper_set_config() helper function to drive the mode setting
 278  * sequence.
 279  *
 280  * Returns:
 281  * True if the mode was set successfully, false otherwise.
 282  */
 283 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 284                               struct drm_display_mode *mode,
 285                               int x, int y,
 286                               struct drm_framebuffer *old_fb)
 287 {
 288         struct drm_device *dev = crtc->dev;
 289         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
 290         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 291         const struct drm_encoder_helper_funcs *encoder_funcs;
 292         int saved_x, saved_y;
 293         bool saved_enabled;
 294         struct drm_encoder *encoder;
 295         bool ret = true;
 296
 297         drm_WARN_ON(dev, drm_drv_uses_atomic_modeset(dev));
 298
 299         drm_warn_on_modeset_not_all_locked(dev);
 300
 301         saved_enabled = crtc->enabled;
 302         crtc->enabled = drm_helper_crtc_in_use(crtc);
 303         if (!crtc->enabled)
 304                 return true;
 305
 306         adjusted_mode = drm_mode_duplicate(dev, mode);
 307         if (!adjusted_mode) {
 308                 crtc->enabled = saved_enabled;
 309                 return false;
 310         }
 311
 312         drm_mode_init(&saved_mode, &crtc->mode);
 313         drm_mode_init(&saved_hwmode, &crtc->hwmode);
 314         saved_x = crtc->x;
 315         saved_y = crtc->y;
 316
 317         /* Update crtc values up front so the driver can rely on them for mode
 318          * setting.
 319          */
 320         drm_mode_copy(&crtc->mode, mode);
 321         crtc->x = x;
 322         crtc->y = y;
 323
 324         /* Pass our mode to the connectors and the CRTC to give them a chance to
 325          * adjust it according to limitations or connector properties, and also
 326          * a chance to reject the mode entirely.
 327          */
 328         drm_for_each_encoder(encoder, dev) {
 329
 330                 if (encoder->crtc != crtc)
 331                         continue;
 332
 333                 encoder_funcs = encoder->helper_private;
 334                 if (!encoder_funcs)
 335                         continue;
 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_dbg_kms(dev, "[ENCODER:%d:%s] mode fixup failed\n",
 342                                             encoder->base.id, encoder->name);
 343                                 goto done;
 344                         }
 345                 }
 346         }
 347
 348         if (crtc_funcs->mode_fixup) {
 349                 if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
 350                                                 adjusted_mode))) {
 351                         drm_dbg_kms(dev, "[CRTC:%d:%s] mode fixup failed\n",
 352                                     crtc->base.id, crtc->name);
 353                         goto done;
 354                 }
 355         }
 356         drm_dbg_kms(dev, "[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
 357
 358         drm_mode_copy(&crtc->hwmode, adjusted_mode);
 359
 360         /* Prepare the encoders and CRTCs before setting the mode. */
 361         drm_for_each_encoder(encoder, dev) {
 362
 363                 if (encoder->crtc != crtc)
 364                         continue;
 365
 366                 encoder_funcs = encoder->helper_private;
 367                 if (!encoder_funcs)
 368                         continue;
 369
 370                 /* Disable the encoders as the first thing we do. */
 371                 if (encoder_funcs->prepare)
 372                         encoder_funcs->prepare(encoder);
 373         }
 374
 375         drm_crtc_prepare_encoders(dev);
 376
 377         crtc_funcs->prepare(crtc);
 378
 379         /* Set up the DPLL and any encoders state that needs to adjust or depend
 380          * on the DPLL.
 381          */
 382         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
 383         if (!ret)
 384             goto done;
 385
 386         drm_for_each_encoder(encoder, dev) {
 387
 388                 if (encoder->crtc != crtc)
 389                         continue;
 390
 391                 encoder_funcs = encoder->helper_private;
 392                 if (!encoder_funcs)
 393                         continue;
 394
 395                 drm_dbg_kms(dev, "[ENCODER:%d:%s] set [MODE:%s]\n",
 396                             encoder->base.id, encoder->name, mode->name);
 397                 if (encoder_funcs->mode_set)
 398                         encoder_funcs->mode_set(encoder, mode, adjusted_mode);
 399         }
 400
 401         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
 402         crtc_funcs->commit(crtc);
 403
 404         drm_for_each_encoder(encoder, dev) {
 405
 406                 if (encoder->crtc != crtc)
 407                         continue;
 408
 409                 encoder_funcs = encoder->helper_private;
 410                 if (!encoder_funcs)
 411                         continue;
 412
 413                 if (encoder_funcs->commit)
 414                         encoder_funcs->commit(encoder);
 415         }
 416
 417         /* Calculate and store various constants which
 418          * are later needed by vblank and swap-completion
 419          * timestamping. They are derived from true hwmode.
 420          */
 421         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
 422
 423         /* FIXME: add subpixel order */
 424 done:
 425         drm_mode_destroy(dev, adjusted_mode);
 426         if (!ret) {
 427                 crtc->enabled = saved_enabled;
 428                 drm_mode_copy(&crtc->mode, &saved_mode);
 429                 drm_mode_copy(&crtc->hwmode, &saved_hwmode);
 430                 crtc->x = saved_x;
 431                 crtc->y = saved_y;
 432         }
 433
 434         return ret;
 435 }
 436 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
 437
 438 /**
 439  * drm_crtc_helper_atomic_check() - Helper to check CRTC atomic-state
 440  * @crtc: CRTC to check
 441  * @state: atomic state object
 442  *
 443  * Provides a default CRTC-state check handler for CRTCs that only have
 444  * one primary plane attached to it. This is often the case for the CRTC
 445  * of simple framebuffers.
 446  *
 447  * RETURNS:
 448  * Zero on success, or an errno code otherwise.
 449  */
 450 int drm_crtc_helper_atomic_check(struct drm_crtc *crtc, struct drm_atomic_state *state)
 451 {
 452         struct drm_crtc_state *new_crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
 453
 454         if (!new_crtc_state->enable)
 455                 return 0;
 456
 457         return drm_atomic_helper_check_crtc_primary_plane(new_crtc_state);
 458 }
 459 EXPORT_SYMBOL(drm_crtc_helper_atomic_check);
 460
 461 static void
 462 drm_crtc_helper_disable(struct drm_crtc *crtc)
 463 {
 464         struct drm_device *dev = crtc->dev;
 465         struct drm_connector *connector;
 466         struct drm_encoder *encoder;
 467
 468         /* Decouple all encoders and their attached connectors from this crtc */
 469         drm_for_each_encoder(encoder, dev) {
 470                 struct drm_connector_list_iter conn_iter;
 471
 472                 if (encoder->crtc != crtc)
 473                         continue;
 474
 475                 drm_connector_list_iter_begin(dev, &conn_iter);
 476                 drm_for_each_connector_iter(connector, &conn_iter) {
 477                         if (connector->encoder != encoder)
 478                                 continue;
 479
 480                         connector->encoder = NULL;
 481
 482                         /*
 483                          * drm_helper_disable_unused_functions() ought to be
 484                          * doing this, but since we've decoupled the encoder
 485                          * from the connector above, the required connection
 486                          * between them is henceforth no longer available.
 487                          */
 488                         connector->dpms = DRM_MODE_DPMS_OFF;
 489
 490                         /* we keep a reference while the encoder is bound */
 491                         drm_connector_put(connector);
 492                 }
 493                 drm_connector_list_iter_end(&conn_iter);
 494         }
 495
 496         __drm_helper_disable_unused_functions(dev);
 497 }
 498
 499 /*
 500  * For connectors that support multiple encoders, either the
 501  * .atomic_best_encoder() or .best_encoder() operation must be implemented.
 502  */
 503 struct drm_encoder *
 504 drm_connector_get_single_encoder(struct drm_connector *connector)
 505 {
 506         struct drm_encoder *encoder;
 507
 508         drm_WARN_ON(connector->dev, hweight32(connector->possible_encoders) > 1);
 509         drm_connector_for_each_possible_encoder(connector, encoder)
 510                 return encoder;
 511
 512         return NULL;
 513 }
 514
 515 /**
 516  * drm_crtc_helper_set_config - set a new config from userspace
 517  * @set: mode set configuration
 518  * @ctx: lock acquire context, not used here
 519  *
 520  * The drm_crtc_helper_set_config() helper function implements the of
 521  * &drm_crtc_funcs.set_config callback for drivers using the legacy CRTC
 522  * helpers.
 523  *
 524  * It first tries to locate the best encoder for each connector by calling the
 525  * connector @drm_connector_helper_funcs.best_encoder helper operation.
 526  *
 527  * After locating the appropriate encoders, the helper function will call the
 528  * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
 529  * or reject it completely in which case an error will be returned to the
 530  * application. If the new configuration after mode adjustment is identical to
 531  * the current configuration the helper function will return without performing
 532  * any other operation.
 533  *
 534  * If the adjusted mode is identical to the current mode but changes to the
 535  * frame buffer need to be applied, the drm_crtc_helper_set_config() function
 536  * will call the CRTC &drm_crtc_helper_funcs.mode_set_base helper operation.
 537  *
 538  * If the adjusted mode differs from the current mode, or if the
 539  * ->mode_set_base() helper operation is not provided, the helper function
 540  * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
 541  * and ->commit() CRTC and encoder helper operations, in that order.
 542  * Alternatively it can also use the dpms and disable helper operations. For
 543  * details see &struct drm_crtc_helper_funcs and struct
 544  * &drm_encoder_helper_funcs.
 545  *
 546  * This function is deprecated.  New drivers must implement atomic modeset
 547  * support, for which this function is unsuitable. Instead drivers should use
 548  * drm_atomic_helper_set_config().
 549  *
 550  * Returns:
 551  * Returns 0 on success, negative errno numbers on failure.
 552  */
 553 int drm_crtc_helper_set_config(struct drm_mode_set *set,
 554                                struct drm_modeset_acquire_ctx *ctx)
 555 {
 556         struct drm_device *dev;
 557         struct drm_crtc **save_encoder_crtcs, *new_crtc;
 558         struct drm_encoder **save_connector_encoders, *new_encoder, *encoder;
 559         bool mode_changed = false; /* if true do a full mode set */
 560         bool fb_changed = false; /* if true and !mode_changed just do a flip */
 561         struct drm_connector *connector;
 562         struct drm_connector_list_iter conn_iter;
 563         int count = 0, ro, fail = 0;
 564         const struct drm_crtc_helper_funcs *crtc_funcs;
 565         struct drm_mode_set save_set;
 566         int ret;
 567         int i;
 568
 569         BUG_ON(!set);
 570         BUG_ON(!set->crtc);
 571         BUG_ON(!set->crtc->helper_private);
 572
 573         /* Enforce sane interface api - has been abused by the fb helper. */
 574         BUG_ON(!set->mode && set->fb);
 575         BUG_ON(set->fb && set->num_connectors == 0);
 576
 577         crtc_funcs = set->crtc->helper_private;
 578
 579         dev = set->crtc->dev;
 580
 581         drm_dbg_kms(dev, "\n");
 582
 583         drm_WARN_ON(dev, drm_drv_uses_atomic_modeset(dev));
 584
 585         if (!set->mode)
 586                 set->fb = NULL;
 587
 588         if (set->fb) {
 589                 drm_dbg_kms(dev, "[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
 590                             set->crtc->base.id, set->crtc->name,
 591                             set->fb->base.id,
 592                             (int)set->num_connectors, set->x, set->y);
 593         } else {
 594                 drm_dbg_kms(dev, "[CRTC:%d:%s] [NOFB]\n",
 595                             set->crtc->base.id, set->crtc->name);
 596                 drm_crtc_helper_disable(set->crtc);
 597                 return 0;
 598         }
 599
 600         drm_warn_on_modeset_not_all_locked(dev);
 601
 602         /*
 603          * Allocate space for the backup of all (non-pointer) encoder and
 604          * connector data.
 605          */
 606         save_encoder_crtcs = kcalloc(dev->mode_config.num_encoder,
 607                                 sizeof(struct drm_crtc *), GFP_KERNEL);
 608         if (!save_encoder_crtcs)
 609                 return -ENOMEM;
 610
 611         save_connector_encoders = kcalloc(dev->mode_config.num_connector,
 612                                 sizeof(struct drm_encoder *), GFP_KERNEL);
 613         if (!save_connector_encoders) {
 614                 kfree(save_encoder_crtcs);
 615                 return -ENOMEM;
 616         }
 617
 618         /*
 619          * Copy data. Note that driver private data is not affected.
 620          * Should anything bad happen only the expected state is
 621          * restored, not the drivers personal bookkeeping.
 622          */
 623         count = 0;
 624         drm_for_each_encoder(encoder, dev) {
 625                 save_encoder_crtcs[count++] = encoder->crtc;
 626         }
 627
 628         count = 0;
 629         drm_connector_list_iter_begin(dev, &conn_iter);
 630         drm_for_each_connector_iter(connector, &conn_iter)
 631                 save_connector_encoders[count++] = connector->encoder;
 632         drm_connector_list_iter_end(&conn_iter);
 633
 634         save_set.crtc = set->crtc;
 635         save_set.mode = &set->crtc->mode;
 636         save_set.x = set->crtc->x;
 637         save_set.y = set->crtc->y;
 638         save_set.fb = set->crtc->primary->fb;
 639
 640         /* We should be able to check here if the fb has the same properties
 641          * and then just flip_or_move it */
 642         if (set->crtc->primary->fb != set->fb) {
 643                 /* If we have no fb then treat it as a full mode set */
 644                 if (set->crtc->primary->fb == NULL) {
 645                         drm_dbg_kms(dev, "[CRTC:%d:%s] no fb, full mode set\n",
 646                                     set->crtc->base.id, set->crtc->name);
 647                         mode_changed = true;
 648                 } else if (set->fb->format != set->crtc->primary->fb->format) {
 649                         mode_changed = true;
 650                 } else
 651                         fb_changed = true;
 652         }
 653
 654         if (set->x != set->crtc->x || set->y != set->crtc->y)
 655                 fb_changed = true;
 656
 657         if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
 658                 drm_dbg_kms(dev, "[CRTC:%d:%s] modes are different, full mode set:\n",
 659                             set->crtc->base.id, set->crtc->name);
 660                 drm_dbg_kms(dev, DRM_MODE_FMT "\n", DRM_MODE_ARG(&set->crtc->mode));
 661                 drm_dbg_kms(dev, DRM_MODE_FMT "\n", DRM_MODE_ARG(set->mode));
 662                 mode_changed = true;
 663         }
 664
 665         /* take a reference on all unbound connectors in set, reuse the
 666          * already taken reference for bound connectors
 667          */
 668         for (ro = 0; ro < set->num_connectors; ro++) {
 669                 if (set->connectors[ro]->encoder)
 670                         continue;
 671                 drm_connector_get(set->connectors[ro]);
 672         }
 673
 674         /* a) traverse passed in connector list and get encoders for them */
 675         count = 0;
 676         drm_connector_list_iter_begin(dev, &conn_iter);
 677         drm_for_each_connector_iter(connector, &conn_iter) {
 678                 const struct drm_connector_helper_funcs *connector_funcs =
 679                         connector->helper_private;
 680                 new_encoder = connector->encoder;
 681                 for (ro = 0; ro < set->num_connectors; ro++) {
 682                         if (set->connectors[ro] == connector) {
 683                                 if (connector_funcs->best_encoder)
 684                                         new_encoder = connector_funcs->best_encoder(connector);
 685                                 else
 686                                         new_encoder = drm_connector_get_single_encoder(connector);
 687
 688                                 /* if we can't get an encoder for a connector
 689                                    we are setting now - then fail */
 690                                 if (new_encoder == NULL)
 691                                         /* don't break so fail path works correct */
 692                                         fail = 1;
 693
 694                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
 695                                         drm_dbg_kms(dev, "[CONNECTOR:%d:%s] DPMS not on, full mode switch\n",
 696                                                     connector->base.id, connector->name);
 697                                         mode_changed = true;
 698                                 }
 699
 700                                 break;
 701                         }
 702                 }
 703
 704                 if (new_encoder != connector->encoder) {
 705                         drm_dbg_kms(dev, "[CONNECTOR:%d:%s] encoder changed, full mode switch\n",
 706                                     connector->base.id, connector->name);
 707                         mode_changed = true;
 708                         /* If the encoder is reused for another connector, then
 709                          * the appropriate crtc will be set later.
 710                          */
 711                         if (connector->encoder)
 712                                 connector->encoder->crtc = NULL;
 713                         connector->encoder = new_encoder;
 714                 }
 715         }
 716         drm_connector_list_iter_end(&conn_iter);
 717
 718         if (fail) {
 719                 ret = -EINVAL;
 720                 goto fail;
 721         }
 722
 723         count = 0;
 724         drm_connector_list_iter_begin(dev, &conn_iter);
 725         drm_for_each_connector_iter(connector, &conn_iter) {
 726                 if (!connector->encoder)
 727                         continue;
 728
 729                 if (connector->encoder->crtc == set->crtc)
 730                         new_crtc = NULL;
 731                 else
 732                         new_crtc = connector->encoder->crtc;
 733
 734                 for (ro = 0; ro < set->num_connectors; ro++) {
 735                         if (set->connectors[ro] == connector)
 736                                 new_crtc = set->crtc;
 737                 }
 738
 739                 /* Make sure the new CRTC will work with the encoder */
 740                 if (new_crtc &&
 741                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
 742                         ret = -EINVAL;
 743                         drm_connector_list_iter_end(&conn_iter);
 744                         goto fail;
 745                 }
 746                 if (new_crtc != connector->encoder->crtc) {
 747                         drm_dbg_kms(dev, "[CONNECTOR:%d:%s] CRTC changed, full mode switch\n",
 748                                     connector->base.id, connector->name);
 749                         mode_changed = true;
 750                         connector->encoder->crtc = new_crtc;
 751                 }
 752                 if (new_crtc) {
 753                         drm_dbg_kms(dev, "[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
 754                                     connector->base.id, connector->name,
 755                                     new_crtc->base.id, new_crtc->name);
 756                 } else {
 757                         drm_dbg_kms(dev, "[CONNECTOR:%d:%s] to [NOCRTC]\n",
 758                                     connector->base.id, connector->name);
 759                 }
 760         }
 761         drm_connector_list_iter_end(&conn_iter);
 762
 763         /* mode_set_base is not a required function */
 764         if (fb_changed && !crtc_funcs->mode_set_base)
 765                 mode_changed = true;
 766
 767         if (mode_changed) {
 768                 if (drm_helper_crtc_in_use(set->crtc)) {
 769                         drm_dbg_kms(dev, "[CRTC:%d:%s] attempting to set mode from userspace: " DRM_MODE_FMT "\n",
 770                                     set->crtc->base.id, set->crtc->name, DRM_MODE_ARG(set->mode));
 771                         set->crtc->primary->fb = set->fb;
 772                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
 773                                                       set->x, set->y,
 774                                                       save_set.fb)) {
 775                                 drm_err(dev, "[CRTC:%d:%s] failed to set mode\n",
 776                                         set->crtc->base.id, set->crtc->name);
 777                                 set->crtc->primary->fb = save_set.fb;
 778                                 ret = -EINVAL;
 779                                 goto fail;
 780                         }
 781                         drm_dbg_kms(dev, "[CRTC:%d:%s] Setting connector DPMS state to on\n",
 782                                     set->crtc->base.id, set->crtc->name);
 783                         for (i = 0; i < set->num_connectors; i++) {
 784                                 drm_dbg_kms(dev, "\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
 785                                             set->connectors[i]->name);
 786                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
 787                         }
 788                 }
 789                 __drm_helper_disable_unused_functions(dev);
 790         } else if (fb_changed) {
 791                 set->crtc->x = set->x;
 792                 set->crtc->y = set->y;
 793                 set->crtc->primary->fb = set->fb;
 794                 ret = crtc_funcs->mode_set_base(set->crtc,
 795                                                 set->x, set->y, save_set.fb);
 796                 if (ret != 0) {
 797                         set->crtc->x = save_set.x;
 798                         set->crtc->y = save_set.y;
 799                         set->crtc->primary->fb = save_set.fb;
 800                         goto fail;
 801                 }
 802         }
 803
 804         kfree(save_connector_encoders);
 805         kfree(save_encoder_crtcs);
 806         return 0;
 807
 808 fail:
 809         /* Restore all previous data. */
 810         count = 0;
 811         drm_for_each_encoder(encoder, dev) {
 812                 encoder->crtc = save_encoder_crtcs[count++];
 813         }
 814
 815         count = 0;
 816         drm_connector_list_iter_begin(dev, &conn_iter);
 817         drm_for_each_connector_iter(connector, &conn_iter)
 818                 connector->encoder = save_connector_encoders[count++];
 819         drm_connector_list_iter_end(&conn_iter);
 820
 821         /* after fail drop reference on all unbound connectors in set, let
 822          * bound connectors keep their reference
 823          */
 824         for (ro = 0; ro < set->num_connectors; ro++) {
 825                 if (set->connectors[ro]->encoder)
 826                         continue;
 827                 drm_connector_put(set->connectors[ro]);
 828         }
 829
 830         /* Try to restore the config */
 831         if (mode_changed &&
 832             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
 833                                       save_set.y, save_set.fb))
 834                 drm_err(dev, "failed to restore config after modeset failure\n");
 835
 836         kfree(save_connector_encoders);
 837         kfree(save_encoder_crtcs);
 838         return ret;
 839 }
 840 EXPORT_SYMBOL(drm_crtc_helper_set_config);
 841
 842 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
 843 {
 844         int dpms = DRM_MODE_DPMS_OFF;
 845         struct drm_connector *connector;
 846         struct drm_connector_list_iter conn_iter;
 847         struct drm_device *dev = encoder->dev;
 848
 849         drm_connector_list_iter_begin(dev, &conn_iter);
 850         drm_for_each_connector_iter(connector, &conn_iter)
 851                 if (connector->encoder == encoder)
 852                         if (connector->dpms < dpms)
 853                                 dpms = connector->dpms;
 854         drm_connector_list_iter_end(&conn_iter);
 855
 856         return dpms;
 857 }
 858
 859 /* Helper which handles bridge ordering around encoder dpms */
 860 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
 861 {
 862         const struct drm_encoder_helper_funcs *encoder_funcs;
 863
 864         encoder_funcs = encoder->helper_private;
 865         if (!encoder_funcs)
 866                 return;
 867
 868         if (encoder_funcs->dpms)
 869                 encoder_funcs->dpms(encoder, mode);
 870 }
 871
 872 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
 873 {
 874         int dpms = DRM_MODE_DPMS_OFF;
 875         struct drm_connector *connector;
 876         struct drm_connector_list_iter conn_iter;
 877         struct drm_device *dev = crtc->dev;
 878
 879         drm_connector_list_iter_begin(dev, &conn_iter);
 880         drm_for_each_connector_iter(connector, &conn_iter)
 881                 if (connector->encoder && connector->encoder->crtc == crtc)
 882                         if (connector->dpms < dpms)
 883                                 dpms = connector->dpms;
 884         drm_connector_list_iter_end(&conn_iter);
 885
 886         return dpms;
 887 }
 888
 889 /**
 890  * drm_helper_connector_dpms() - connector dpms helper implementation
 891  * @connector: affected connector
 892  * @mode: DPMS mode
 893  *
 894  * The drm_helper_connector_dpms() helper function implements the
 895  * &drm_connector_funcs.dpms callback for drivers using the legacy CRTC
 896  * helpers.
 897  *
 898  * This is the main helper function provided by the CRTC helper framework for
 899  * implementing the DPMS connector attribute. It computes the new desired DPMS
 900  * state for all encoders and CRTCs in the output mesh and calls the
 901  * &drm_crtc_helper_funcs.dpms and &drm_encoder_helper_funcs.dpms callbacks
 902  * provided by the driver.
 903  *
 904  * This function is deprecated.  New drivers must implement atomic modeset
 905  * support, where DPMS is handled in the DRM core.
 906  *
 907  * Returns:
 908  * Always returns 0.
 909  */
 910 int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
 911 {
 912         struct drm_encoder *encoder = connector->encoder;
 913         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
 914         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
 915
 916         drm_WARN_ON(connector->dev, drm_drv_uses_atomic_modeset(connector->dev));
 917
 918         if (mode == connector->dpms)
 919                 return 0;
 920
 921         old_dpms = connector->dpms;
 922         connector->dpms = mode;
 923
 924         if (encoder)
 925                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
 926
 927         /* from off to on, do crtc then encoder */
 928         if (mode < old_dpms) {
 929                 if (crtc) {
 930                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 931
 932                         if (crtc_funcs->dpms)
 933                                 (*crtc_funcs->dpms) (crtc,
 934                                                      drm_helper_choose_crtc_dpms(crtc));
 935                 }
 936                 if (encoder)
 937                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 938         }
 939
 940         /* from on to off, do encoder then crtc */
 941         if (mode > old_dpms) {
 942                 if (encoder)
 943                         drm_helper_encoder_dpms(encoder, encoder_dpms);
 944                 if (crtc) {
 945                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
 946
 947                         if (crtc_funcs->dpms)
 948                                 (*crtc_funcs->dpms) (crtc,
 949                                                      drm_helper_choose_crtc_dpms(crtc));
 950                 }
 951         }
 952
 953         return 0;
 954 }
 955 EXPORT_SYMBOL(drm_helper_connector_dpms);
 956
 957 /**
 958  * drm_helper_resume_force_mode - force-restore mode setting configuration
 959  * @dev: drm_device which should be restored
 960  *
 961  * Drivers which use the mode setting helpers can use this function to
 962  * force-restore the mode setting configuration e.g. on resume or when something
 963  * else might have trampled over the hw state (like some overzealous old BIOSen
 964  * tended to do).
 965  *
 966  * This helper doesn't provide a error return value since restoring the old
 967  * config should never fail due to resource allocation issues since the driver
 968  * has successfully set the restored configuration already. Hence this should
 969  * boil down to the equivalent of a few dpms on calls, which also don't provide
 970  * an error code.
 971  *
 972  * Drivers where simply restoring an old configuration again might fail (e.g.
 973  * due to slight differences in allocating shared resources when the
 974  * configuration is restored in a different order than when userspace set it up)
 975  * need to use their own restore logic.
 976  *
 977  * This function is deprecated. New drivers should implement atomic mode-
 978  * setting and use the atomic suspend/resume helpers.
 979  *
 980  * See also:
 981  * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 982  */
 983 void drm_helper_resume_force_mode(struct drm_device *dev)
 984 {
 985         struct drm_crtc *crtc;
 986         struct drm_encoder *encoder;
 987         const struct drm_crtc_helper_funcs *crtc_funcs;
 988         int encoder_dpms;
 989         bool ret;
 990
 991         drm_WARN_ON(dev, drm_drv_uses_atomic_modeset(dev));
 992
 993         drm_modeset_lock_all(dev);
 994         drm_for_each_crtc(crtc, dev) {
 995
 996                 if (!crtc->enabled)
 997                         continue;
 998
 999                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
1000                                                crtc->x, crtc->y, crtc->primary->fb);
1001
1002                 /* Restoring the old config should never fail! */
1003                 if (ret == false)
1004                         drm_err(dev, "failed to set mode on crtc %p\n", crtc);
1005
1006                 /* Turn off outputs that were already powered off */
1007                 if (drm_helper_choose_crtc_dpms(crtc)) {
1008                         drm_for_each_encoder(encoder, dev) {
1009
1010                                 if(encoder->crtc != crtc)
1011                                         continue;
1012
1013                                 encoder_dpms = drm_helper_choose_encoder_dpms(
1014                                                         encoder);
1015
1016                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
1017                         }
1018
1019                         crtc_funcs = crtc->helper_private;
1020                         if (crtc_funcs->dpms)
1021                                 (*crtc_funcs->dpms) (crtc,
1022                                                      drm_helper_choose_crtc_dpms(crtc));
1023                 }
1024         }
1025
1026         /* disable the unused connectors while restoring the modesetting */
1027         __drm_helper_disable_unused_functions(dev);
1028         drm_modeset_unlock_all(dev);
1029 }
1030 EXPORT_SYMBOL(drm_helper_resume_force_mode);
1031
1032 /**
1033  * drm_helper_force_disable_all - Forcibly turn off all enabled CRTCs
1034  * @dev: DRM device whose CRTCs to turn off
1035  *
1036  * Drivers may want to call this on unload to ensure that all displays are
1037  * unlit and the GPU is in a consistent, low power state. Takes modeset locks.
1038  *
1039  * Note: This should only be used by non-atomic legacy drivers. For an atomic
1040  * version look at drm_atomic_helper_shutdown().
1041  *
1042  * Returns:
1043  * Zero on success, error code on failure.
1044  */
1045 int drm_helper_force_disable_all(struct drm_device *dev)
1046 {
1047         struct drm_crtc *crtc;
1048         int ret = 0;
1049
1050         drm_modeset_lock_all(dev);
1051         drm_for_each_crtc(crtc, dev)
1052                 if (crtc->enabled) {
1053                         struct drm_mode_set set = {
1054                                 .crtc = crtc,
1055                         };
1056
1057                         ret = drm_mode_set_config_internal(&set);
1058                         if (ret)
1059                                 goto out;
1060                 }
1061 out:
1062         drm_modeset_unlock_all(dev);
1063         return ret;
1064 }
1065 EXPORT_SYMBOL(drm_helper_force_disable_all);