drivers/gpu/drm/drm_fb_helper.c

   1 /*
   2  * Copyright (c) 2006-2009 Red Hat Inc.
   3  * Copyright (c) 2006-2008 Intel Corporation
   4  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
   5  *
   6  * DRM framebuffer helper functions
   7  *
   8  * Permission to use, copy, modify, distribute, and sell this software and its
   9  * documentation for any purpose is hereby granted without fee, provided that
  10  * the above copyright notice appear in all copies and that both that copyright
  11  * notice and this permission notice appear in supporting documentation, and
  12  * that the name of the copyright holders not be used in advertising or
  13  * publicity pertaining to distribution of the software without specific,
  14  * written prior permission.  The copyright holders make no representations
  15  * about the suitability of this software for any purpose.  It is provided "as
  16  * is" without express or implied warranty.
  17  *
  18  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  19  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  20  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  21  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  22  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  23  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  24  * OF THIS SOFTWARE.
  25  *
  26  * Authors:
  27  *      Dave Airlie <airlied@linux.ie>
  28  *      Jesse Barnes <jesse.barnes@intel.com>
  29  */
  30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  31
  32 #include <linux/kernel.h>
  33 #include <linux/sysrq.h>
  34 #include <linux/slab.h>
  35 #include <linux/fb.h>
  36 #include <linux/module.h>
  37 #include <drm/drmP.h>
  38 #include <drm/drm_crtc.h>
  39 #include <drm/drm_fb_helper.h>
  40 #include <drm/drm_crtc_helper.h>
  41
  42 static LIST_HEAD(kernel_fb_helper_list);
  43
  44 /**
  45  * DOC: fbdev helpers
  46  *
  47  * The fb helper functions are useful to provide an fbdev on top of a drm kernel
  48  * mode setting driver. They can be used mostly independently from the crtc
  49  * helper functions used by many drivers to implement the kernel mode setting
  50  * interfaces.
  51  *
  52  * Initialization is done as a four-step process with drm_fb_helper_prepare(),
  53  * drm_fb_helper_init(), drm_fb_helper_single_add_all_connectors() and
  54  * drm_fb_helper_initial_config(). Drivers with fancier requirements than the
  55  * default behaviour can override the third step with their own code.
  56  * Teardown is done with drm_fb_helper_fini().
  57  *
  58  * At runtime drivers should restore the fbdev console by calling
  59  * drm_fb_helper_restore_fbdev_mode() from their ->lastclose callback. They
  60  * should also notify the fb helper code from updates to the output
  61  * configuration by calling drm_fb_helper_hotplug_event(). For easier
  62  * integration with the output polling code in drm_crtc_helper.c the modeset
  63  * code provides a ->output_poll_changed callback.
  64  *
  65  * All other functions exported by the fb helper library can be used to
  66  * implement the fbdev driver interface by the driver.
  67  *
  68  * It is possible, though perhaps somewhat tricky, to implement race-free
  69  * hotplug detection using the fbdev helpers. The drm_fb_helper_prepare()
  70  * helper must be called first to initialize the minimum required to make
  71  * hotplug detection work. Drivers also need to make sure to properly set up
  72  * the dev->mode_config.funcs member. After calling drm_kms_helper_poll_init()
  73  * it is safe to enable interrupts and start processing hotplug events. At the
  74  * same time, drivers should initialize all modeset objects such as CRTCs,
  75  * encoders and connectors. To finish up the fbdev helper initialization, the
  76  * drm_fb_helper_init() function is called. To probe for all attached displays
  77  * and set up an initial configuration using the detected hardware, drivers
  78  * should call drm_fb_helper_single_add_all_connectors() followed by
  79  * drm_fb_helper_initial_config().
  80  */
  81
  82 /**
  83  * drm_fb_helper_single_add_all_connectors() - add all connectors to fbdev
  84  *                                             emulation helper
  85  * @fb_helper: fbdev initialized with drm_fb_helper_init
  86  *
  87  * This functions adds all the available connectors for use with the given
  88  * fb_helper. This is a separate step to allow drivers to freely assign
  89  * connectors to the fbdev, e.g. if some are reserved for special purposes or
  90  * not adequate to be used for the fbcon.
  91  *
  92  * This function is protected against concurrent connector hotadds/removals
  93  * using drm_fb_helper_add_one_connector() and
  94  * drm_fb_helper_remove_one_connector().
  95  */
  96 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
  97 {
  98         struct drm_device *dev = fb_helper->dev;
  99         struct drm_connector *connector;
 100         int i;
 101
 102         mutex_lock(&dev->mode_config.mutex);
 103         drm_for_each_connector(connector, dev) {
 104                 struct drm_fb_helper_connector *fb_helper_connector;
 105
 106                 fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
 107                 if (!fb_helper_connector)
 108                         goto fail;
 109
 110                 fb_helper_connector->connector = connector;
 111                 fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
 112         }
 113         mutex_unlock(&dev->mode_config.mutex);
 114         return 0;
 115 fail:
 116         for (i = 0; i < fb_helper->connector_count; i++) {
 117                 kfree(fb_helper->connector_info[i]);
 118                 fb_helper->connector_info[i] = NULL;
 119         }
 120         fb_helper->connector_count = 0;
 121         mutex_unlock(&dev->mode_config.mutex);
 122
 123         return -ENOMEM;
 124 }
 125 EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors);
 126
 127 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector)
 128 {
 129         struct drm_fb_helper_connector **temp;
 130         struct drm_fb_helper_connector *fb_helper_connector;
 131
 132         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
 133         if (fb_helper->connector_count + 1 > fb_helper->connector_info_alloc_count) {
 134                 temp = krealloc(fb_helper->connector_info, sizeof(struct drm_fb_helper_connector *) * (fb_helper->connector_count + 1), GFP_KERNEL);
 135                 if (!temp)
 136                         return -ENOMEM;
 137
 138                 fb_helper->connector_info_alloc_count = fb_helper->connector_count + 1;
 139                 fb_helper->connector_info = temp;
 140         }
 141
 142
 143         fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
 144         if (!fb_helper_connector)
 145                 return -ENOMEM;
 146
 147         fb_helper_connector->connector = connector;
 148         fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
 149         return 0;
 150 }
 151 EXPORT_SYMBOL(drm_fb_helper_add_one_connector);
 152
 153 static void remove_from_modeset(struct drm_mode_set *set,
 154                 struct drm_connector *connector)
 155 {
 156         int i, j;
 157
 158         for (i = 0; i < set->num_connectors; i++) {
 159                 if (set->connectors[i] == connector)
 160                         break;
 161         }
 162
 163         if (i == set->num_connectors)
 164                 return;
 165
 166         for (j = i + 1; j < set->num_connectors; j++) {
 167                 set->connectors[j - 1] = set->connectors[j];
 168         }
 169         set->num_connectors--;
 170
 171         /* because i915 is pissy about this..
 172          * TODO maybe need to makes sure we set it back to !=NULL somewhere?
 173          */
 174         if (set->num_connectors == 0)
 175                 set->fb = NULL;
 176 }
 177
 178 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 179                                        struct drm_connector *connector)
 180 {
 181         struct drm_fb_helper_connector *fb_helper_connector;
 182         int i, j;
 183
 184         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
 185
 186         for (i = 0; i < fb_helper->connector_count; i++) {
 187                 if (fb_helper->connector_info[i]->connector == connector)
 188                         break;
 189         }
 190
 191         if (i == fb_helper->connector_count)
 192                 return -EINVAL;
 193         fb_helper_connector = fb_helper->connector_info[i];
 194
 195         for (j = i + 1; j < fb_helper->connector_count; j++) {
 196                 fb_helper->connector_info[j - 1] = fb_helper->connector_info[j];
 197         }
 198         fb_helper->connector_count--;
 199         kfree(fb_helper_connector);
 200
 201         /* also cleanup dangling references to the connector: */
 202         for (i = 0; i < fb_helper->crtc_count; i++)
 203                 remove_from_modeset(&fb_helper->crtc_info[i].mode_set, connector);
 204
 205         return 0;
 206 }
 207 EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
 208
 209 static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
 210 {
 211         uint16_t *r_base, *g_base, *b_base;
 212         int i;
 213
 214         if (helper->funcs->gamma_get == NULL)
 215                 return;
 216
 217         r_base = crtc->gamma_store;
 218         g_base = r_base + crtc->gamma_size;
 219         b_base = g_base + crtc->gamma_size;
 220
 221         for (i = 0; i < crtc->gamma_size; i++)
 222                 helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
 223 }
 224
 225 static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
 226 {
 227         uint16_t *r_base, *g_base, *b_base;
 228
 229         if (crtc->funcs->gamma_set == NULL)
 230                 return;
 231
 232         r_base = crtc->gamma_store;
 233         g_base = r_base + crtc->gamma_size;
 234         b_base = g_base + crtc->gamma_size;
 235
 236         crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, 0, crtc->gamma_size);
 237 }
 238
 239 /**
 240  * drm_fb_helper_debug_enter - implementation for ->fb_debug_enter
 241  * @info: fbdev registered by the helper
 242  */
 243 int drm_fb_helper_debug_enter(struct fb_info *info)
 244 {
 245         struct drm_fb_helper *helper = info->par;
 246         const struct drm_crtc_helper_funcs *funcs;
 247         int i;
 248
 249         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 250                 for (i = 0; i < helper->crtc_count; i++) {
 251                         struct drm_mode_set *mode_set =
 252                                 &helper->crtc_info[i].mode_set;
 253
 254                         if (!mode_set->crtc->enabled)
 255                                 continue;
 256
 257                         funcs = mode_set->crtc->helper_private;
 258                         drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
 259                         funcs->mode_set_base_atomic(mode_set->crtc,
 260                                                     mode_set->fb,
 261                                                     mode_set->x,
 262                                                     mode_set->y,
 263                                                     ENTER_ATOMIC_MODE_SET);
 264                 }
 265         }
 266
 267         return 0;
 268 }
 269 EXPORT_SYMBOL(drm_fb_helper_debug_enter);
 270
 271 /* Find the real fb for a given fb helper CRTC */
 272 static struct drm_framebuffer *drm_mode_config_fb(struct drm_crtc *crtc)
 273 {
 274         struct drm_device *dev = crtc->dev;
 275         struct drm_crtc *c;
 276
 277         drm_for_each_crtc(c, dev) {
 278                 if (crtc->base.id == c->base.id)
 279                         return c->primary->fb;
 280         }
 281
 282         return NULL;
 283 }
 284
 285 /**
 286  * drm_fb_helper_debug_leave - implementation for ->fb_debug_leave
 287  * @info: fbdev registered by the helper
 288  */
 289 int drm_fb_helper_debug_leave(struct fb_info *info)
 290 {
 291         struct drm_fb_helper *helper = info->par;
 292         struct drm_crtc *crtc;
 293         const struct drm_crtc_helper_funcs *funcs;
 294         struct drm_framebuffer *fb;
 295         int i;
 296
 297         for (i = 0; i < helper->crtc_count; i++) {
 298                 struct drm_mode_set *mode_set = &helper->crtc_info[i].mode_set;
 299                 crtc = mode_set->crtc;
 300                 funcs = crtc->helper_private;
 301                 fb = drm_mode_config_fb(crtc);
 302
 303                 if (!crtc->enabled)
 304                         continue;
 305
 306                 if (!fb) {
 307                         DRM_ERROR("no fb to restore??\n");
 308                         continue;
 309                 }
 310
 311                 drm_fb_helper_restore_lut_atomic(mode_set->crtc);
 312                 funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
 313                                             crtc->y, LEAVE_ATOMIC_MODE_SET);
 314         }
 315
 316         return 0;
 317 }
 318 EXPORT_SYMBOL(drm_fb_helper_debug_leave);
 319
 320 static bool restore_fbdev_mode(struct drm_fb_helper *fb_helper)
 321 {
 322         struct drm_device *dev = fb_helper->dev;
 323         struct drm_plane *plane;
 324         bool error = false;
 325         int i;
 326
 327         drm_warn_on_modeset_not_all_locked(dev);
 328
 329         drm_for_each_plane(plane, dev) {
 330                 if (plane->type != DRM_PLANE_TYPE_PRIMARY)
 331                         drm_plane_force_disable(plane);
 332
 333                 if (dev->mode_config.rotation_property) {
 334                         drm_mode_plane_set_obj_prop(plane,
 335                                                     dev->mode_config.rotation_property,
 336                                                     BIT(DRM_ROTATE_0));
 337                 }
 338         }
 339
 340         for (i = 0; i < fb_helper->crtc_count; i++) {
 341                 struct drm_mode_set *mode_set = &fb_helper->crtc_info[i].mode_set;
 342                 struct drm_crtc *crtc = mode_set->crtc;
 343                 int ret;
 344
 345                 if (crtc->funcs->cursor_set) {
 346                         ret = crtc->funcs->cursor_set(crtc, NULL, 0, 0, 0);
 347                         if (ret)
 348                                 error = true;
 349                 }
 350
 351                 ret = drm_mode_set_config_internal(mode_set);
 352                 if (ret)
 353                         error = true;
 354         }
 355         return error;
 356 }
 357 /**
 358  * drm_fb_helper_restore_fbdev_mode - restore fbdev configuration
 359  * @fb_helper: fbcon to restore
 360  *
 361  * This should be called from driver's drm ->lastclose callback
 362  * when implementing an fbcon on top of kms using this helper. This ensures that
 363  * the user isn't greeted with a black screen when e.g. X dies.
 364  *
 365  * Use this variant if you need to bypass locking (panic), or already
 366  * hold all modeset locks.  Otherwise use drm_fb_helper_restore_fbdev_mode_unlocked()
 367  */
 368 static bool drm_fb_helper_restore_fbdev_mode(struct drm_fb_helper *fb_helper)
 369 {
 370         return restore_fbdev_mode(fb_helper);
 371 }
 372
 373 /**
 374  * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration
 375  * @fb_helper: fbcon to restore
 376  *
 377  * This should be called from driver's drm ->lastclose callback
 378  * when implementing an fbcon on top of kms using this helper. This ensures that
 379  * the user isn't greeted with a black screen when e.g. X dies.
 380  */
 381 bool drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
 382 {
 383         struct drm_device *dev = fb_helper->dev;
 384         bool ret;
 385         bool do_delayed = false;
 386
 387         drm_modeset_lock_all(dev);
 388         ret = restore_fbdev_mode(fb_helper);
 389
 390         do_delayed = fb_helper->delayed_hotplug;
 391         if (do_delayed)
 392                 fb_helper->delayed_hotplug = false;
 393         drm_modeset_unlock_all(dev);
 394
 395         if (do_delayed)
 396                 drm_fb_helper_hotplug_event(fb_helper);
 397         return ret;
 398 }
 399 EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked);
 400
 401 /*
 402  * restore fbcon display for all kms driver's using this helper, used for sysrq
 403  * and panic handling.
 404  */
 405 static bool drm_fb_helper_force_kernel_mode(void)
 406 {
 407         bool ret, error = false;
 408         struct drm_fb_helper *helper;
 409
 410         if (list_empty(&kernel_fb_helper_list))
 411                 return false;
 412
 413         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 414                 struct drm_device *dev = helper->dev;
 415
 416                 if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
 417                         continue;
 418
 419                 /*
 420                  * NOTE: Use trylock mode to avoid deadlocks and sleeping in
 421                  * panic context.
 422                  */
 423                 if (__drm_modeset_lock_all(dev, true) != 0) {
 424                         error = true;
 425                         continue;
 426                 }
 427
 428                 ret = drm_fb_helper_restore_fbdev_mode(helper);
 429                 if (ret)
 430                         error = true;
 431
 432                 drm_modeset_unlock_all(dev);
 433         }
 434         return error;
 435 }
 436
 437 static bool drm_fb_helper_is_bound(struct drm_fb_helper *fb_helper)
 438 {
 439         struct drm_device *dev = fb_helper->dev;
 440         struct drm_crtc *crtc;
 441         int bound = 0, crtcs_bound = 0;
 442
 443         /* Sometimes user space wants everything disabled, so don't steal the
 444          * display if there's a master. */
 445         if (dev->primary->master)
 446                 return false;
 447
 448         drm_for_each_crtc(crtc, dev) {
 449                 if (crtc->primary->fb)
 450                         crtcs_bound++;
 451                 if (crtc->primary->fb == fb_helper->fb)
 452                         bound++;
 453         }
 454
 455         if (bound < crtcs_bound)
 456                 return false;
 457
 458         return true;
 459 }
 460
 461 #ifdef CONFIG_MAGIC_SYSRQ
 462 static void drm_fb_helper_restore_work_fn(struct work_struct *ignored)
 463 {
 464         bool ret;
 465         ret = drm_fb_helper_force_kernel_mode();
 466         if (ret == true)
 467                 DRM_ERROR("Failed to restore crtc configuration\n");
 468 }
 469 static DECLARE_WORK(drm_fb_helper_restore_work, drm_fb_helper_restore_work_fn);
 470
 471 static void drm_fb_helper_sysrq(int dummy1)
 472 {
 473         schedule_work(&drm_fb_helper_restore_work);
 474 }
 475
 476 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = {
 477         .handler = drm_fb_helper_sysrq,
 478         .help_msg = "force-fb(V)",
 479         .action_msg = "Restore framebuffer console",
 480 };
 481 #else
 482 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { };
 483 #endif
 484
 485 static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
 486 {
 487         struct drm_fb_helper *fb_helper = info->par;
 488         struct drm_device *dev = fb_helper->dev;
 489         struct drm_crtc *crtc;
 490         struct drm_connector *connector;
 491         int i, j;
 492
 493         /*
 494          * For each CRTC in this fb, turn the connectors on/off.
 495          */
 496         drm_modeset_lock_all(dev);
 497         if (!drm_fb_helper_is_bound(fb_helper)) {
 498                 drm_modeset_unlock_all(dev);
 499                 return;
 500         }
 501
 502         for (i = 0; i < fb_helper->crtc_count; i++) {
 503                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
 504
 505                 if (!crtc->enabled)
 506                         continue;
 507
 508                 /* Walk the connectors & encoders on this fb turning them on/off */
 509                 for (j = 0; j < fb_helper->connector_count; j++) {
 510                         connector = fb_helper->connector_info[j]->connector;
 511                         connector->funcs->dpms(connector, dpms_mode);
 512                         drm_object_property_set_value(&connector->base,
 513                                 dev->mode_config.dpms_property, dpms_mode);
 514                 }
 515         }
 516         drm_modeset_unlock_all(dev);
 517 }
 518
 519 /**
 520  * drm_fb_helper_blank - implementation for ->fb_blank
 521  * @blank: desired blanking state
 522  * @info: fbdev registered by the helper
 523  */
 524 int drm_fb_helper_blank(int blank, struct fb_info *info)
 525 {
 526         if (oops_in_progress)
 527                 return -EBUSY;
 528
 529         switch (blank) {
 530         /* Display: On; HSync: On, VSync: On */
 531         case FB_BLANK_UNBLANK:
 532                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON);
 533                 break;
 534         /* Display: Off; HSync: On, VSync: On */
 535         case FB_BLANK_NORMAL:
 536                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 537                 break;
 538         /* Display: Off; HSync: Off, VSync: On */
 539         case FB_BLANK_HSYNC_SUSPEND:
 540                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 541                 break;
 542         /* Display: Off; HSync: On, VSync: Off */
 543         case FB_BLANK_VSYNC_SUSPEND:
 544                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND);
 545                 break;
 546         /* Display: Off; HSync: Off, VSync: Off */
 547         case FB_BLANK_POWERDOWN:
 548                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF);
 549                 break;
 550         }
 551         return 0;
 552 }
 553 EXPORT_SYMBOL(drm_fb_helper_blank);
 554
 555 static void drm_fb_helper_crtc_free(struct drm_fb_helper *helper)
 556 {
 557         int i;
 558
 559         for (i = 0; i < helper->connector_count; i++)
 560                 kfree(helper->connector_info[i]);
 561         kfree(helper->connector_info);
 562         for (i = 0; i < helper->crtc_count; i++) {
 563                 kfree(helper->crtc_info[i].mode_set.connectors);
 564                 if (helper->crtc_info[i].mode_set.mode)
 565                         drm_mode_destroy(helper->dev, helper->crtc_info[i].mode_set.mode);
 566         }
 567         kfree(helper->crtc_info);
 568 }
 569
 570 /**
 571  * drm_fb_helper_prepare - setup a drm_fb_helper structure
 572  * @dev: DRM device
 573  * @helper: driver-allocated fbdev helper structure to set up
 574  * @funcs: pointer to structure of functions associate with this helper
 575  *
 576  * Sets up the bare minimum to make the framebuffer helper usable. This is
 577  * useful to implement race-free initialization of the polling helpers.
 578  */
 579 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
 580                            const struct drm_fb_helper_funcs *funcs)
 581 {
 582         INIT_LIST_HEAD(&helper->kernel_fb_list);
 583         helper->funcs = funcs;
 584         helper->dev = dev;
 585 }
 586 EXPORT_SYMBOL(drm_fb_helper_prepare);
 587
 588 /**
 589  * drm_fb_helper_init - initialize a drm_fb_helper structure
 590  * @dev: drm device
 591  * @fb_helper: driver-allocated fbdev helper structure to initialize
 592  * @crtc_count: maximum number of crtcs to support in this fbdev emulation
 593  * @max_conn_count: max connector count
 594  *
 595  * This allocates the structures for the fbdev helper with the given limits.
 596  * Note that this won't yet touch the hardware (through the driver interfaces)
 597  * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
 598  * to allow driver writes more control over the exact init sequence.
 599  *
 600  * Drivers must call drm_fb_helper_prepare() before calling this function.
 601  *
 602  * RETURNS:
 603  * Zero if everything went ok, nonzero otherwise.
 604  */
 605 int drm_fb_helper_init(struct drm_device *dev,
 606                        struct drm_fb_helper *fb_helper,
 607                        int crtc_count, int max_conn_count)
 608 {
 609         struct drm_crtc *crtc;
 610         int i;
 611
 612         if (!max_conn_count)
 613                 return -EINVAL;
 614
 615         fb_helper->crtc_info = kcalloc(crtc_count, sizeof(struct drm_fb_helper_crtc), GFP_KERNEL);
 616         if (!fb_helper->crtc_info)
 617                 return -ENOMEM;
 618
 619         fb_helper->crtc_count = crtc_count;
 620         fb_helper->connector_info = kcalloc(dev->mode_config.num_connector, sizeof(struct drm_fb_helper_connector *), GFP_KERNEL);
 621         if (!fb_helper->connector_info) {
 622                 kfree(fb_helper->crtc_info);
 623                 return -ENOMEM;
 624         }
 625         fb_helper->connector_info_alloc_count = dev->mode_config.num_connector;
 626         fb_helper->connector_count = 0;
 627
 628         for (i = 0; i < crtc_count; i++) {
 629                 fb_helper->crtc_info[i].mode_set.connectors =
 630                         kcalloc(max_conn_count,
 631                                 sizeof(struct drm_connector *),
 632                                 GFP_KERNEL);
 633
 634                 if (!fb_helper->crtc_info[i].mode_set.connectors)
 635                         goto out_free;
 636                 fb_helper->crtc_info[i].mode_set.num_connectors = 0;
 637         }
 638
 639         i = 0;
 640         drm_for_each_crtc(crtc, dev) {
 641                 fb_helper->crtc_info[i].mode_set.crtc = crtc;
 642                 i++;
 643         }
 644
 645         return 0;
 646 out_free:
 647         drm_fb_helper_crtc_free(fb_helper);
 648         return -ENOMEM;
 649 }
 650 EXPORT_SYMBOL(drm_fb_helper_init);
 651
 652 /**
 653  * drm_fb_helper_alloc_fbi - allocate fb_info and some of its members
 654  * @fb_helper: driver-allocated fbdev helper
 655  *
 656  * A helper to alloc fb_info and the members cmap and apertures. Called
 657  * by the driver within the fb_probe fb_helper callback function.
 658  *
 659  * RETURNS:
 660  * fb_info pointer if things went okay, pointer containing error code
 661  * otherwise
 662  */
 663 struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
 664 {
 665         struct device *dev = fb_helper->dev->dev;
 666         struct fb_info *info;
 667         int ret;
 668
 669         info = framebuffer_alloc(0, dev);
 670         if (!info)
 671                 return ERR_PTR(-ENOMEM);
 672
 673         ret = fb_alloc_cmap(&info->cmap, 256, 0);
 674         if (ret)
 675                 goto err_release;
 676
 677         info->apertures = alloc_apertures(1);
 678         if (!info->apertures) {
 679                 ret = -ENOMEM;
 680                 goto err_free_cmap;
 681         }
 682
 683         fb_helper->fbdev = info;
 684
 685         return info;
 686
 687 err_free_cmap:
 688         fb_dealloc_cmap(&info->cmap);
 689 err_release:
 690         framebuffer_release(info);
 691         return ERR_PTR(ret);
 692 }
 693 EXPORT_SYMBOL(drm_fb_helper_alloc_fbi);
 694
 695 /**
 696  * drm_fb_helper_unregister_fbi - unregister fb_info framebuffer device
 697  * @fb_helper: driver-allocated fbdev helper
 698  *
 699  * A wrapper around unregister_framebuffer, to release the fb_info
 700  * framebuffer device
 701  */
 702 void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
 703 {
 704         if (fb_helper && fb_helper->fbdev)
 705                 unregister_framebuffer(fb_helper->fbdev);
 706 }
 707 EXPORT_SYMBOL(drm_fb_helper_unregister_fbi);
 708
 709 /**
 710  * drm_fb_helper_release_fbi - dealloc fb_info and its members
 711  * @fb_helper: driver-allocated fbdev helper
 712  *
 713  * A helper to free memory taken by fb_info and the members cmap and
 714  * apertures
 715  */
 716 void drm_fb_helper_release_fbi(struct drm_fb_helper *fb_helper)
 717 {
 718         if (fb_helper) {
 719                 struct fb_info *info = fb_helper->fbdev;
 720
 721                 if (info) {
 722                         if (info->cmap.len)
 723                                 fb_dealloc_cmap(&info->cmap);
 724                         framebuffer_release(info);
 725                 }
 726
 727                 fb_helper->fbdev = NULL;
 728         }
 729 }
 730 EXPORT_SYMBOL(drm_fb_helper_release_fbi);
 731
 732 void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
 733 {
 734         if (!list_empty(&fb_helper->kernel_fb_list)) {
 735                 list_del(&fb_helper->kernel_fb_list);
 736                 if (list_empty(&kernel_fb_helper_list)) {
 737                         unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
 738                 }
 739         }
 740
 741         drm_fb_helper_crtc_free(fb_helper);
 742
 743 }
 744 EXPORT_SYMBOL(drm_fb_helper_fini);
 745
 746 /**
 747  * drm_fb_helper_unlink_fbi - wrapper around unlink_framebuffer
 748  * @fb_helper: driver-allocated fbdev helper
 749  *
 750  * A wrapper around unlink_framebuffer implemented by fbdev core
 751  */
 752 void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper)
 753 {
 754         if (fb_helper && fb_helper->fbdev)
 755                 unlink_framebuffer(fb_helper->fbdev);
 756 }
 757 EXPORT_SYMBOL(drm_fb_helper_unlink_fbi);
 758
 759 /**
 760  * drm_fb_helper_sys_read - wrapper around fb_sys_read
 761  * @info: fb_info struct pointer
 762  * @buf: userspace buffer to read from framebuffer memory
 763  * @count: number of bytes to read from framebuffer memory
 764  * @ppos: read offset within framebuffer memory
 765  *
 766  * A wrapper around fb_sys_read implemented by fbdev core
 767  */
 768 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
 769                                size_t count, loff_t *ppos)
 770 {
 771         return fb_sys_read(info, buf, count, ppos);
 772 }
 773 EXPORT_SYMBOL(drm_fb_helper_sys_read);
 774
 775 /**
 776  * drm_fb_helper_sys_write - wrapper around fb_sys_write
 777  * @info: fb_info struct pointer
 778  * @buf: userspace buffer to write to framebuffer memory
 779  * @count: number of bytes to write to framebuffer memory
 780  * @ppos: write offset within framebuffer memory
 781  *
 782  * A wrapper around fb_sys_write implemented by fbdev core
 783  */
 784 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
 785                                 size_t count, loff_t *ppos)
 786 {
 787         return fb_sys_write(info, buf, count, ppos);
 788 }
 789 EXPORT_SYMBOL(drm_fb_helper_sys_write);
 790
 791 /**
 792  * drm_fb_helper_sys_fillrect - wrapper around sys_fillrect
 793  * @info: fbdev registered by the helper
 794  * @rect: info about rectangle to fill
 795  *
 796  * A wrapper around sys_fillrect implemented by fbdev core
 797  */
 798 void drm_fb_helper_sys_fillrect(struct fb_info *info,
 799                                 const struct fb_fillrect *rect)
 800 {
 801         sys_fillrect(info, rect);
 802 }
 803 EXPORT_SYMBOL(drm_fb_helper_sys_fillrect);
 804
 805 /**
 806  * drm_fb_helper_sys_copyarea - wrapper around sys_copyarea
 807  * @info: fbdev registered by the helper
 808  * @area: info about area to copy
 809  *
 810  * A wrapper around sys_copyarea implemented by fbdev core
 811  */
 812 void drm_fb_helper_sys_copyarea(struct fb_info *info,
 813                                 const struct fb_copyarea *area)
 814 {
 815         sys_copyarea(info, area);
 816 }
 817 EXPORT_SYMBOL(drm_fb_helper_sys_copyarea);
 818
 819 /**
 820  * drm_fb_helper_sys_imageblit - wrapper around sys_imageblit
 821  * @info: fbdev registered by the helper
 822  * @image: info about image to blit
 823  *
 824  * A wrapper around sys_imageblit implemented by fbdev core
 825  */
 826 void drm_fb_helper_sys_imageblit(struct fb_info *info,
 827                                  const struct fb_image *image)
 828 {
 829         sys_imageblit(info, image);
 830 }
 831 EXPORT_SYMBOL(drm_fb_helper_sys_imageblit);
 832
 833 /**
 834  * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect
 835  * @info: fbdev registered by the helper
 836  * @rect: info about rectangle to fill
 837  *
 838  * A wrapper around cfb_imageblit implemented by fbdev core
 839  */
 840 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
 841                                 const struct fb_fillrect *rect)
 842 {
 843         cfb_fillrect(info, rect);
 844 }
 845 EXPORT_SYMBOL(drm_fb_helper_cfb_fillrect);
 846
 847 /**
 848  * drm_fb_helper_cfb_copyarea - wrapper around cfb_copyarea
 849  * @info: fbdev registered by the helper
 850  * @area: info about area to copy
 851  *
 852  * A wrapper around cfb_copyarea implemented by fbdev core
 853  */
 854 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
 855                                 const struct fb_copyarea *area)
 856 {
 857         cfb_copyarea(info, area);
 858 }
 859 EXPORT_SYMBOL(drm_fb_helper_cfb_copyarea);
 860
 861 /**
 862  * drm_fb_helper_cfb_imageblit - wrapper around cfb_imageblit
 863  * @info: fbdev registered by the helper
 864  * @image: info about image to blit
 865  *
 866  * A wrapper around cfb_imageblit implemented by fbdev core
 867  */
 868 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
 869                                  const struct fb_image *image)
 870 {
 871         cfb_imageblit(info, image);
 872 }
 873 EXPORT_SYMBOL(drm_fb_helper_cfb_imageblit);
 874
 875 /**
 876  * drm_fb_helper_set_suspend - wrapper around fb_set_suspend
 877  * @fb_helper: driver-allocated fbdev helper
 878  * @state: desired state, zero to resume, non-zero to suspend
 879  *
 880  * A wrapper around fb_set_suspend implemented by fbdev core
 881  */
 882 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, int state)
 883 {
 884         if (fb_helper && fb_helper->fbdev)
 885                 fb_set_suspend(fb_helper->fbdev, state);
 886 }
 887 EXPORT_SYMBOL(drm_fb_helper_set_suspend);
 888
 889 static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
 890                      u16 blue, u16 regno, struct fb_info *info)
 891 {
 892         struct drm_fb_helper *fb_helper = info->par;
 893         struct drm_framebuffer *fb = fb_helper->fb;
 894         int pindex;
 895
 896         if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
 897                 u32 *palette;
 898                 u32 value;
 899                 /* place color in psuedopalette */
 900                 if (regno > 16)
 901                         return -EINVAL;
 902                 palette = (u32 *)info->pseudo_palette;
 903                 red >>= (16 - info->var.red.length);
 904                 green >>= (16 - info->var.green.length);
 905                 blue >>= (16 - info->var.blue.length);
 906                 value = (red << info->var.red.offset) |
 907                         (green << info->var.green.offset) |
 908                         (blue << info->var.blue.offset);
 909                 if (info->var.transp.length > 0) {
 910                         u32 mask = (1 << info->var.transp.length) - 1;
 911                         mask <<= info->var.transp.offset;
 912                         value |= mask;
 913                 }
 914                 palette[regno] = value;
 915                 return 0;
 916         }
 917
 918         /*
 919          * The driver really shouldn't advertise pseudo/directcolor
 920          * visuals if it can't deal with the palette.
 921          */
 922         if (WARN_ON(!fb_helper->funcs->gamma_set ||
 923                     !fb_helper->funcs->gamma_get))
 924                 return -EINVAL;
 925
 926         pindex = regno;
 927
 928         if (fb->bits_per_pixel == 16) {
 929                 pindex = regno << 3;
 930
 931                 if (fb->depth == 16 && regno > 63)
 932                         return -EINVAL;
 933                 if (fb->depth == 15 && regno > 31)
 934                         return -EINVAL;
 935
 936                 if (fb->depth == 16) {
 937                         u16 r, g, b;
 938                         int i;
 939                         if (regno < 32) {
 940                                 for (i = 0; i < 8; i++)
 941                                         fb_helper->funcs->gamma_set(crtc, red,
 942                                                 green, blue, pindex + i);
 943                         }
 944
 945                         fb_helper->funcs->gamma_get(crtc, &r,
 946                                                     &g, &b,
 947                                                     pindex >> 1);
 948
 949                         for (i = 0; i < 4; i++)
 950                                 fb_helper->funcs->gamma_set(crtc, r,
 951                                                             green, b,
 952                                                             (pindex >> 1) + i);
 953                 }
 954         }
 955
 956         if (fb->depth != 16)
 957                 fb_helper->funcs->gamma_set(crtc, red, green, blue, pindex);
 958         return 0;
 959 }
 960
 961 /**
 962  * drm_fb_helper_setcmap - implementation for ->fb_setcmap
 963  * @cmap: cmap to set
 964  * @info: fbdev registered by the helper
 965  */
 966 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
 967 {
 968         struct drm_fb_helper *fb_helper = info->par;
 969         struct drm_device *dev = fb_helper->dev;
 970         const struct drm_crtc_helper_funcs *crtc_funcs;
 971         u16 *red, *green, *blue, *transp;
 972         struct drm_crtc *crtc;
 973         int i, j, rc = 0;
 974         int start;
 975
 976         if (oops_in_progress)
 977                 return -EBUSY;
 978
 979         drm_modeset_lock_all(dev);
 980         if (!drm_fb_helper_is_bound(fb_helper)) {
 981                 drm_modeset_unlock_all(dev);
 982                 return -EBUSY;
 983         }
 984
 985         for (i = 0; i < fb_helper->crtc_count; i++) {
 986                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
 987                 crtc_funcs = crtc->helper_private;
 988
 989                 red = cmap->red;
 990                 green = cmap->green;
 991                 blue = cmap->blue;
 992                 transp = cmap->transp;
 993                 start = cmap->start;
 994
 995                 for (j = 0; j < cmap->len; j++) {
 996                         u16 hred, hgreen, hblue, htransp = 0xffff;
 997
 998                         hred = *red++;
 999                         hgreen = *green++;
1000                         hblue = *blue++;
1001
1002                         if (transp)
1003                                 htransp = *transp++;
1004
1005                         rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
1006                         if (rc)
1007                                 goto out;
1008                 }
1009                 if (crtc_funcs->load_lut)
1010                         crtc_funcs->load_lut(crtc);
1011         }
1012  out:
1013         drm_modeset_unlock_all(dev);
1014         return rc;
1015 }
1016 EXPORT_SYMBOL(drm_fb_helper_setcmap);
1017
1018 /**
1019  * drm_fb_helper_check_var - implementation for ->fb_check_var
1020  * @var: screeninfo to check
1021  * @info: fbdev registered by the helper
1022  */
1023 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
1024                             struct fb_info *info)
1025 {
1026         struct drm_fb_helper *fb_helper = info->par;
1027         struct drm_framebuffer *fb = fb_helper->fb;
1028         int depth;
1029
1030         if (var->pixclock != 0 || in_dbg_master())
1031                 return -EINVAL;
1032
1033         /* Need to resize the fb object !!! */
1034         if (var->bits_per_pixel > fb->bits_per_pixel ||
1035             var->xres > fb->width || var->yres > fb->height ||
1036             var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
1037                 DRM_DEBUG("fb userspace requested width/height/bpp is greater than current fb "
1038                           "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
1039                           var->xres, var->yres, var->bits_per_pixel,
1040                           var->xres_virtual, var->yres_virtual,
1041                           fb->width, fb->height, fb->bits_per_pixel);
1042                 return -EINVAL;
1043         }
1044
1045         switch (var->bits_per_pixel) {
1046         case 16:
1047                 depth = (var->green.length == 6) ? 16 : 15;
1048                 break;
1049         case 32:
1050                 depth = (var->transp.length > 0) ? 32 : 24;
1051                 break;
1052         default:
1053                 depth = var->bits_per_pixel;
1054                 break;
1055         }
1056
1057         switch (depth) {
1058         case 8:
1059                 var->red.offset = 0;
1060                 var->green.offset = 0;
1061                 var->blue.offset = 0;
1062                 var->red.length = 8;
1063                 var->green.length = 8;
1064                 var->blue.length = 8;
1065                 var->transp.length = 0;
1066                 var->transp.offset = 0;
1067                 break;
1068         case 15:
1069                 var->red.offset = 10;
1070                 var->green.offset = 5;
1071                 var->blue.offset = 0;
1072                 var->red.length = 5;
1073                 var->green.length = 5;
1074                 var->blue.length = 5;
1075                 var->transp.length = 1;
1076                 var->transp.offset = 15;
1077                 break;
1078         case 16:
1079                 var->red.offset = 11;
1080                 var->green.offset = 5;
1081                 var->blue.offset = 0;
1082                 var->red.length = 5;
1083                 var->green.length = 6;
1084                 var->blue.length = 5;
1085                 var->transp.length = 0;
1086                 var->transp.offset = 0;
1087                 break;
1088         case 24:
1089                 var->red.offset = 16;
1090                 var->green.offset = 8;
1091                 var->blue.offset = 0;
1092                 var->red.length = 8;
1093                 var->green.length = 8;
1094                 var->blue.length = 8;
1095                 var->transp.length = 0;
1096                 var->transp.offset = 0;
1097                 break;
1098         case 32:
1099                 var->red.offset = 16;
1100                 var->green.offset = 8;
1101                 var->blue.offset = 0;
1102                 var->red.length = 8;
1103                 var->green.length = 8;
1104                 var->blue.length = 8;
1105                 var->transp.length = 8;
1106                 var->transp.offset = 24;
1107                 break;
1108         default:
1109                 return -EINVAL;
1110         }
1111         return 0;
1112 }
1113 EXPORT_SYMBOL(drm_fb_helper_check_var);
1114
1115 /**
1116  * drm_fb_helper_set_par - implementation for ->fb_set_par
1117  * @info: fbdev registered by the helper
1118  *
1119  * This will let fbcon do the mode init and is called at initialization time by
1120  * the fbdev core when registering the driver, and later on through the hotplug
1121  * callback.
1122  */
1123 int drm_fb_helper_set_par(struct fb_info *info)
1124 {
1125         struct drm_fb_helper *fb_helper = info->par;
1126         struct fb_var_screeninfo *var = &info->var;
1127
1128         if (oops_in_progress)
1129                 return -EBUSY;
1130
1131         if (var->pixclock != 0) {
1132                 DRM_ERROR("PIXEL CLOCK SET\n");
1133                 return -EINVAL;
1134         }
1135
1136         drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper);
1137
1138         return 0;
1139 }
1140 EXPORT_SYMBOL(drm_fb_helper_set_par);
1141
1142 /**
1143  * drm_fb_helper_pan_display - implementation for ->fb_pan_display
1144  * @var: updated screen information
1145  * @info: fbdev registered by the helper
1146  */
1147 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
1148                               struct fb_info *info)
1149 {
1150         struct drm_fb_helper *fb_helper = info->par;
1151         struct drm_device *dev = fb_helper->dev;
1152         struct drm_mode_set *modeset;
1153         int ret = 0;
1154         int i;
1155
1156         if (oops_in_progress)
1157                 return -EBUSY;
1158
1159         drm_modeset_lock_all(dev);
1160         if (!drm_fb_helper_is_bound(fb_helper)) {
1161                 drm_modeset_unlock_all(dev);
1162                 return -EBUSY;
1163         }
1164
1165         for (i = 0; i < fb_helper->crtc_count; i++) {
1166                 modeset = &fb_helper->crtc_info[i].mode_set;
1167
1168                 modeset->x = var->xoffset;
1169                 modeset->y = var->yoffset;
1170
1171                 if (modeset->num_connectors) {
1172                         ret = drm_mode_set_config_internal(modeset);
1173                         if (!ret) {
1174                                 info->var.xoffset = var->xoffset;
1175                                 info->var.yoffset = var->yoffset;
1176                         }
1177                 }
1178         }
1179         drm_modeset_unlock_all(dev);
1180         return ret;
1181 }
1182 EXPORT_SYMBOL(drm_fb_helper_pan_display);
1183
1184 /*
1185  * Allocates the backing storage and sets up the fbdev info structure through
1186  * the ->fb_probe callback and then registers the fbdev and sets up the panic
1187  * notifier.
1188  */
1189 static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
1190                                          int preferred_bpp)
1191 {
1192         int ret = 0;
1193         int crtc_count = 0;
1194         int i;
1195         struct fb_info *info;
1196         struct drm_fb_helper_surface_size sizes;
1197         int gamma_size = 0;
1198
1199         memset(&sizes, 0, sizeof(struct drm_fb_helper_surface_size));
1200         sizes.surface_depth = 24;
1201         sizes.surface_bpp = 32;
1202         sizes.fb_width = (unsigned)-1;
1203         sizes.fb_height = (unsigned)-1;
1204
1205         /* if driver picks 8 or 16 by default use that
1206            for both depth/bpp */
1207         if (preferred_bpp != sizes.surface_bpp)
1208                 sizes.surface_depth = sizes.surface_bpp = preferred_bpp;
1209
1210         /* first up get a count of crtcs now in use and new min/maxes width/heights */
1211         for (i = 0; i < fb_helper->connector_count; i++) {
1212                 struct drm_fb_helper_connector *fb_helper_conn = fb_helper->connector_info[i];
1213                 struct drm_cmdline_mode *cmdline_mode;
1214
1215                 cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1216
1217                 if (cmdline_mode->bpp_specified) {
1218                         switch (cmdline_mode->bpp) {
1219                         case 8:
1220                                 sizes.surface_depth = sizes.surface_bpp = 8;
1221                                 break;
1222                         case 15:
1223                                 sizes.surface_depth = 15;
1224                                 sizes.surface_bpp = 16;
1225                                 break;
1226                         case 16:
1227                                 sizes.surface_depth = sizes.surface_bpp = 16;
1228                                 break;
1229                         case 24:
1230                                 sizes.surface_depth = sizes.surface_bpp = 24;
1231                                 break;
1232                         case 32:
1233                                 sizes.surface_depth = 24;
1234                                 sizes.surface_bpp = 32;
1235                                 break;
1236                         }
1237                         break;
1238                 }
1239         }
1240
1241         crtc_count = 0;
1242         for (i = 0; i < fb_helper->crtc_count; i++) {
1243                 struct drm_display_mode *desired_mode;
1244                 struct drm_mode_set *mode_set;
1245                 int x, y, j;
1246                 /* in case of tile group, are we the last tile vert or horiz?
1247                  * If no tile group you are always the last one both vertically
1248                  * and horizontally
1249                  */
1250                 bool lastv = true, lasth = true;
1251
1252                 desired_mode = fb_helper->crtc_info[i].desired_mode;
1253                 mode_set = &fb_helper->crtc_info[i].mode_set;
1254
1255                 if (!desired_mode)
1256                         continue;
1257
1258                 crtc_count++;
1259
1260                 x = fb_helper->crtc_info[i].x;
1261                 y = fb_helper->crtc_info[i].y;
1262
1263                 if (gamma_size == 0)
1264                         gamma_size = fb_helper->crtc_info[i].mode_set.crtc->gamma_size;
1265
1266                 sizes.surface_width  = max_t(u32, desired_mode->hdisplay + x, sizes.surface_width);
1267                 sizes.surface_height = max_t(u32, desired_mode->vdisplay + y, sizes.surface_height);
1268
1269                 for (j = 0; j < mode_set->num_connectors; j++) {
1270                         struct drm_connector *connector = mode_set->connectors[j];
1271                         if (connector->has_tile) {
1272                                 lasth = (connector->tile_h_loc == (connector->num_h_tile - 1));
1273                                 lastv = (connector->tile_v_loc == (connector->num_v_tile - 1));
1274                                 /* cloning to multiple tiles is just crazy-talk, so: */
1275                                 break;
1276                         }
1277                 }
1278
1279                 if (lasth)
1280                         sizes.fb_width  = min_t(u32, desired_mode->hdisplay + x, sizes.fb_width);
1281                 if (lastv)
1282                         sizes.fb_height = min_t(u32, desired_mode->vdisplay + y, sizes.fb_height);
1283         }
1284
1285         if (crtc_count == 0 || sizes.fb_width == -1 || sizes.fb_height == -1) {
1286                 /* hmm everyone went away - assume VGA cable just fell out
1287                    and will come back later. */
1288                 DRM_INFO("Cannot find any crtc or sizes - going 1024x768\n");
1289                 sizes.fb_width = sizes.surface_width = 1024;
1290                 sizes.fb_height = sizes.surface_height = 768;
1291         }
1292
1293         /* push down into drivers */
1294         ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);
1295         if (ret < 0)
1296                 return ret;
1297
1298         info = fb_helper->fbdev;
1299
1300         /*
1301          * Set the fb pointer - usually drm_setup_crtcs does this for hotplug
1302          * events, but at init time drm_setup_crtcs needs to be called before
1303          * the fb is allocated (since we need to figure out the desired size of
1304          * the fb before we can allocate it ...). Hence we need to fix things up
1305          * here again.
1306          */
1307         for (i = 0; i < fb_helper->crtc_count; i++)
1308                 if (fb_helper->crtc_info[i].mode_set.num_connectors)
1309                         fb_helper->crtc_info[i].mode_set.fb = fb_helper->fb;
1310
1311
1312         info->var.pixclock = 0;
1313         if (register_framebuffer(info) < 0)
1314                 return -EINVAL;
1315
1316         dev_info(fb_helper->dev->dev, "fb%d: %s frame buffer device\n",
1317                         info->node, info->fix.id);
1318
1319         if (list_empty(&kernel_fb_helper_list)) {
1320                 register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
1321         }
1322
1323         list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
1324
1325         return 0;
1326 }
1327
1328 /**
1329  * drm_fb_helper_fill_fix - initializes fixed fbdev information
1330  * @info: fbdev registered by the helper
1331  * @pitch: desired pitch
1332  * @depth: desired depth
1333  *
1334  * Helper to fill in the fixed fbdev information useful for a non-accelerated
1335  * fbdev emulations. Drivers which support acceleration methods which impose
1336  * additional constraints need to set up their own limits.
1337  *
1338  * Drivers should call this (or their equivalent setup code) from their
1339  * ->fb_probe callback.
1340  */
1341 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
1342                             uint32_t depth)
1343 {
1344         info->fix.type = FB_TYPE_PACKED_PIXELS;
1345         info->fix.visual = depth == 8 ? FB_VISUAL_PSEUDOCOLOR :
1346                 FB_VISUAL_TRUECOLOR;
1347         info->fix.mmio_start = 0;
1348         info->fix.mmio_len = 0;
1349         info->fix.type_aux = 0;
1350         info->fix.xpanstep = 1; /* doing it in hw */
1351         info->fix.ypanstep = 1; /* doing it in hw */
1352         info->fix.ywrapstep = 0;
1353         info->fix.accel = FB_ACCEL_NONE;
1354
1355         info->fix.line_length = pitch;
1356         return;
1357 }
1358 EXPORT_SYMBOL(drm_fb_helper_fill_fix);
1359
1360 /**
1361  * drm_fb_helper_fill_var - initalizes variable fbdev information
1362  * @info: fbdev instance to set up
1363  * @fb_helper: fb helper instance to use as template
1364  * @fb_width: desired fb width
1365  * @fb_height: desired fb height
1366  *
1367  * Sets up the variable fbdev metainformation from the given fb helper instance
1368  * and the drm framebuffer allocated in fb_helper->fb.
1369  *
1370  * Drivers should call this (or their equivalent setup code) from their
1371  * ->fb_probe callback after having allocated the fbdev backing
1372  * storage framebuffer.
1373  */
1374 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
1375                             uint32_t fb_width, uint32_t fb_height)
1376 {
1377         struct drm_framebuffer *fb = fb_helper->fb;
1378         info->pseudo_palette = fb_helper->pseudo_palette;
1379         info->var.xres_virtual = fb->width;
1380         info->var.yres_virtual = fb->height;
1381         info->var.bits_per_pixel = fb->bits_per_pixel;
1382         info->var.accel_flags = FB_ACCELF_TEXT;
1383         info->var.xoffset = 0;
1384         info->var.yoffset = 0;
1385         info->var.activate = FB_ACTIVATE_NOW;
1386         info->var.height = -1;
1387         info->var.width = -1;
1388
1389         switch (fb->depth) {
1390         case 8:
1391                 info->var.red.offset = 0;
1392                 info->var.green.offset = 0;
1393                 info->var.blue.offset = 0;
1394                 info->var.red.length = 8; /* 8bit DAC */
1395                 info->var.green.length = 8;
1396                 info->var.blue.length = 8;
1397                 info->var.transp.offset = 0;
1398                 info->var.transp.length = 0;
1399                 break;
1400         case 15:
1401                 info->var.red.offset = 10;
1402                 info->var.green.offset = 5;
1403                 info->var.blue.offset = 0;
1404                 info->var.red.length = 5;
1405                 info->var.green.length = 5;
1406                 info->var.blue.length = 5;
1407                 info->var.transp.offset = 15;
1408                 info->var.transp.length = 1;
1409                 break;
1410         case 16:
1411                 info->var.red.offset = 11;
1412                 info->var.green.offset = 5;
1413                 info->var.blue.offset = 0;
1414                 info->var.red.length = 5;
1415                 info->var.green.length = 6;
1416                 info->var.blue.length = 5;
1417                 info->var.transp.offset = 0;
1418                 break;
1419         case 24:
1420                 info->var.red.offset = 16;
1421                 info->var.green.offset = 8;
1422                 info->var.blue.offset = 0;
1423                 info->var.red.length = 8;
1424                 info->var.green.length = 8;
1425                 info->var.blue.length = 8;
1426                 info->var.transp.offset = 0;
1427                 info->var.transp.length = 0;
1428                 break;
1429         case 32:
1430                 info->var.red.offset = 16;
1431                 info->var.green.offset = 8;
1432                 info->var.blue.offset = 0;
1433                 info->var.red.length = 8;
1434                 info->var.green.length = 8;
1435                 info->var.blue.length = 8;
1436                 info->var.transp.offset = 24;
1437                 info->var.transp.length = 8;
1438                 break;
1439         default:
1440                 break;
1441         }
1442
1443         info->var.xres = fb_width;
1444         info->var.yres = fb_height;
1445 }
1446 EXPORT_SYMBOL(drm_fb_helper_fill_var);
1447
1448 static int drm_fb_helper_probe_connector_modes(struct drm_fb_helper *fb_helper,
1449                                                uint32_t maxX,
1450                                                uint32_t maxY)
1451 {
1452         struct drm_connector *connector;
1453         int count = 0;
1454         int i;
1455
1456         for (i = 0; i < fb_helper->connector_count; i++) {
1457                 connector = fb_helper->connector_info[i]->connector;
1458                 count += connector->funcs->fill_modes(connector, maxX, maxY);
1459         }
1460
1461         return count;
1462 }
1463
1464 struct drm_display_mode *drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector, int width, int height)
1465 {
1466         struct drm_display_mode *mode;
1467
1468         list_for_each_entry(mode, &fb_connector->connector->modes, head) {
1469                 if (mode->hdisplay > width ||
1470                     mode->vdisplay > height)
1471                         continue;
1472                 if (mode->type & DRM_MODE_TYPE_PREFERRED)
1473                         return mode;
1474         }
1475         return NULL;
1476 }
1477 EXPORT_SYMBOL(drm_has_preferred_mode);
1478
1479 static bool drm_has_cmdline_mode(struct drm_fb_helper_connector *fb_connector)
1480 {
1481         return fb_connector->connector->cmdline_mode.specified;
1482 }
1483
1484 struct drm_display_mode *drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
1485                                                       int width, int height)
1486 {
1487         struct drm_cmdline_mode *cmdline_mode;
1488         struct drm_display_mode *mode;
1489         bool prefer_non_interlace;
1490
1491         cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1492         if (cmdline_mode->specified == false)
1493                 return NULL;
1494
1495         /* attempt to find a matching mode in the list of modes
1496          *  we have gotten so far, if not add a CVT mode that conforms
1497          */
1498         if (cmdline_mode->rb || cmdline_mode->margins)
1499                 goto create_mode;
1500
1501         prefer_non_interlace = !cmdline_mode->interlace;
1502 again:
1503         list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1504                 /* check width/height */
1505                 if (mode->hdisplay != cmdline_mode->xres ||
1506                     mode->vdisplay != cmdline_mode->yres)
1507                         continue;
1508
1509                 if (cmdline_mode->refresh_specified) {
1510                         if (mode->vrefresh != cmdline_mode->refresh)
1511                                 continue;
1512                 }
1513
1514                 if (cmdline_mode->interlace) {
1515                         if (!(mode->flags & DRM_MODE_FLAG_INTERLACE))
1516                                 continue;
1517                 } else if (prefer_non_interlace) {
1518                         if (mode->flags & DRM_MODE_FLAG_INTERLACE)
1519                                 continue;
1520                 }
1521                 return mode;
1522         }
1523
1524         if (prefer_non_interlace) {
1525                 prefer_non_interlace = false;
1526                 goto again;
1527         }
1528
1529 create_mode:
1530         mode = drm_mode_create_from_cmdline_mode(fb_helper_conn->connector->dev,
1531                                                  cmdline_mode);
1532         list_add(&mode->head, &fb_helper_conn->connector->modes);
1533         return mode;
1534 }
1535 EXPORT_SYMBOL(drm_pick_cmdline_mode);
1536
1537 static bool drm_connector_enabled(struct drm_connector *connector, bool strict)
1538 {
1539         bool enable;
1540
1541         if (strict)
1542                 enable = connector->status == connector_status_connected;
1543         else
1544                 enable = connector->status != connector_status_disconnected;
1545
1546         return enable;
1547 }
1548
1549 static void drm_enable_connectors(struct drm_fb_helper *fb_helper,
1550                                   bool *enabled)
1551 {
1552         bool any_enabled = false;
1553         struct drm_connector *connector;
1554         int i = 0;
1555
1556         for (i = 0; i < fb_helper->connector_count; i++) {
1557                 connector = fb_helper->connector_info[i]->connector;
1558                 enabled[i] = drm_connector_enabled(connector, true);
1559                 DRM_DEBUG_KMS("connector %d enabled? %s\n", connector->base.id,
1560                           enabled[i] ? "yes" : "no");
1561                 any_enabled |= enabled[i];
1562         }
1563
1564         if (any_enabled)
1565                 return;
1566
1567         for (i = 0; i < fb_helper->connector_count; i++) {
1568                 connector = fb_helper->connector_info[i]->connector;
1569                 enabled[i] = drm_connector_enabled(connector, false);
1570         }
1571 }
1572
1573 static bool drm_target_cloned(struct drm_fb_helper *fb_helper,
1574                               struct drm_display_mode **modes,
1575                               struct drm_fb_offset *offsets,
1576                               bool *enabled, int width, int height)
1577 {
1578         int count, i, j;
1579         bool can_clone = false;
1580         struct drm_fb_helper_connector *fb_helper_conn;
1581         struct drm_display_mode *dmt_mode, *mode;
1582
1583         /* only contemplate cloning in the single crtc case */
1584         if (fb_helper->crtc_count > 1)
1585                 return false;
1586
1587         count = 0;
1588         for (i = 0; i < fb_helper->connector_count; i++) {
1589                 if (enabled[i])
1590                         count++;
1591         }
1592
1593         /* only contemplate cloning if more than one connector is enabled */
1594         if (count <= 1)
1595                 return false;
1596
1597         /* check the command line or if nothing common pick 1024x768 */
1598         can_clone = true;
1599         for (i = 0; i < fb_helper->connector_count; i++) {
1600                 if (!enabled[i])
1601                         continue;
1602                 fb_helper_conn = fb_helper->connector_info[i];
1603                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1604                 if (!modes[i]) {
1605                         can_clone = false;
1606                         break;
1607                 }
1608                 for (j = 0; j < i; j++) {
1609                         if (!enabled[j])
1610                                 continue;
1611                         if (!drm_mode_equal(modes[j], modes[i]))
1612                                 can_clone = false;
1613                 }
1614         }
1615
1616         if (can_clone) {
1617                 DRM_DEBUG_KMS("can clone using command line\n");
1618                 return true;
1619         }
1620
1621         /* try and find a 1024x768 mode on each connector */
1622         can_clone = true;
1623         dmt_mode = drm_mode_find_dmt(fb_helper->dev, 1024, 768, 60, false);
1624
1625         for (i = 0; i < fb_helper->connector_count; i++) {
1626
1627                 if (!enabled[i])
1628                         continue;
1629
1630                 fb_helper_conn = fb_helper->connector_info[i];
1631                 list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1632                         if (drm_mode_equal(mode, dmt_mode))
1633                                 modes[i] = mode;
1634                 }
1635                 if (!modes[i])
1636                         can_clone = false;
1637         }
1638
1639         if (can_clone) {
1640                 DRM_DEBUG_KMS("can clone using 1024x768\n");
1641                 return true;
1642         }
1643         DRM_INFO("kms: can't enable cloning when we probably wanted to.\n");
1644         return false;
1645 }
1646
1647 static int drm_get_tile_offsets(struct drm_fb_helper *fb_helper,
1648                                 struct drm_display_mode **modes,
1649                                 struct drm_fb_offset *offsets,
1650                                 int idx,
1651                                 int h_idx, int v_idx)
1652 {
1653         struct drm_fb_helper_connector *fb_helper_conn;
1654         int i;
1655         int hoffset = 0, voffset = 0;
1656
1657         for (i = 0; i < fb_helper->connector_count; i++) {
1658                 fb_helper_conn = fb_helper->connector_info[i];
1659                 if (!fb_helper_conn->connector->has_tile)
1660                         continue;
1661
1662                 if (!modes[i] && (h_idx || v_idx)) {
1663                         DRM_DEBUG_KMS("no modes for connector tiled %d %d\n", i,
1664                                       fb_helper_conn->connector->base.id);
1665                         continue;
1666                 }
1667                 if (fb_helper_conn->connector->tile_h_loc < h_idx)
1668                         hoffset += modes[i]->hdisplay;
1669
1670                 if (fb_helper_conn->connector->tile_v_loc < v_idx)
1671                         voffset += modes[i]->vdisplay;
1672         }
1673         offsets[idx].x = hoffset;
1674         offsets[idx].y = voffset;
1675         DRM_DEBUG_KMS("returned %d %d for %d %d\n", hoffset, voffset, h_idx, v_idx);
1676         return 0;
1677 }
1678
1679 static bool drm_target_preferred(struct drm_fb_helper *fb_helper,
1680                                  struct drm_display_mode **modes,
1681                                  struct drm_fb_offset *offsets,
1682                                  bool *enabled, int width, int height)
1683 {
1684         struct drm_fb_helper_connector *fb_helper_conn;
1685         int i;
1686         uint64_t conn_configured = 0, mask;
1687         int tile_pass = 0;
1688         mask = (1 << fb_helper->connector_count) - 1;
1689 retry:
1690         for (i = 0; i < fb_helper->connector_count; i++) {
1691                 fb_helper_conn = fb_helper->connector_info[i];
1692
1693                 if (conn_configured & (1 << i))
1694                         continue;
1695
1696                 if (enabled[i] == false) {
1697                         conn_configured |= (1 << i);
1698                         continue;
1699                 }
1700
1701                 /* first pass over all the untiled connectors */
1702                 if (tile_pass == 0 && fb_helper_conn->connector->has_tile)
1703                         continue;
1704
1705                 if (tile_pass == 1) {
1706                         if (fb_helper_conn->connector->tile_h_loc != 0 ||
1707                             fb_helper_conn->connector->tile_v_loc != 0)
1708                                 continue;
1709
1710                 } else {
1711                         if (fb_helper_conn->connector->tile_h_loc != tile_pass -1 &&
1712                             fb_helper_conn->connector->tile_v_loc != tile_pass - 1)
1713                         /* if this tile_pass doesn't cover any of the tiles - keep going */
1714                                 continue;
1715
1716                         /* find the tile offsets for this pass - need
1717                            to find all tiles left and above */
1718                         drm_get_tile_offsets(fb_helper, modes, offsets,
1719                                              i, fb_helper_conn->connector->tile_h_loc, fb_helper_conn->connector->tile_v_loc);
1720                 }
1721                 DRM_DEBUG_KMS("looking for cmdline mode on connector %d\n",
1722                               fb_helper_conn->connector->base.id);
1723
1724                 /* got for command line mode first */
1725                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1726                 if (!modes[i]) {
1727                         DRM_DEBUG_KMS("looking for preferred mode on connector %d %d\n",
1728                                       fb_helper_conn->connector->base.id, fb_helper_conn->connector->tile_group ? fb_helper_conn->connector->tile_group->id : 0);
1729                         modes[i] = drm_has_preferred_mode(fb_helper_conn, width, height);
1730                 }
1731                 /* No preferred modes, pick one off the list */
1732                 if (!modes[i] && !list_empty(&fb_helper_conn->connector->modes)) {
1733                         list_for_each_entry(modes[i], &fb_helper_conn->connector->modes, head)
1734                                 break;
1735                 }
1736                 DRM_DEBUG_KMS("found mode %s\n", modes[i] ? modes[i]->name :
1737                           "none");
1738                 conn_configured |= (1 << i);
1739         }
1740
1741         if ((conn_configured & mask) != mask) {
1742                 tile_pass++;
1743                 goto retry;
1744         }
1745         return true;
1746 }
1747
1748 static int drm_pick_crtcs(struct drm_fb_helper *fb_helper,
1749                           struct drm_fb_helper_crtc **best_crtcs,
1750                           struct drm_display_mode **modes,
1751                           int n, int width, int height)
1752 {
1753         int c, o;
1754         struct drm_device *dev = fb_helper->dev;
1755         struct drm_connector *connector;
1756         const struct drm_connector_helper_funcs *connector_funcs;
1757         struct drm_encoder *encoder;
1758         int my_score, best_score, score;
1759         struct drm_fb_helper_crtc **crtcs, *crtc;
1760         struct drm_fb_helper_connector *fb_helper_conn;
1761
1762         if (n == fb_helper->connector_count)
1763                 return 0;
1764
1765         fb_helper_conn = fb_helper->connector_info[n];
1766         connector = fb_helper_conn->connector;
1767
1768         best_crtcs[n] = NULL;
1769         best_score = drm_pick_crtcs(fb_helper, best_crtcs, modes, n+1, width, height);
1770         if (modes[n] == NULL)
1771                 return best_score;
1772
1773         crtcs = kzalloc(dev->mode_config.num_connector *
1774                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1775         if (!crtcs)
1776                 return best_score;
1777
1778         my_score = 1;
1779         if (connector->status == connector_status_connected)
1780                 my_score++;
1781         if (drm_has_cmdline_mode(fb_helper_conn))
1782                 my_score++;
1783         if (drm_has_preferred_mode(fb_helper_conn, width, height))
1784                 my_score++;
1785
1786         connector_funcs = connector->helper_private;
1787         encoder = connector_funcs->best_encoder(connector);
1788         if (!encoder)
1789                 goto out;
1790
1791         /* select a crtc for this connector and then attempt to configure
1792            remaining connectors */
1793         for (c = 0; c < fb_helper->crtc_count; c++) {
1794                 crtc = &fb_helper->crtc_info[c];
1795
1796                 if ((encoder->possible_crtcs & (1 << c)) == 0)
1797                         continue;
1798
1799                 for (o = 0; o < n; o++)
1800                         if (best_crtcs[o] == crtc)
1801                                 break;
1802
1803                 if (o < n) {
1804                         /* ignore cloning unless only a single crtc */
1805                         if (fb_helper->crtc_count > 1)
1806                                 continue;
1807
1808                         if (!drm_mode_equal(modes[o], modes[n]))
1809                                 continue;
1810                 }
1811
1812                 crtcs[n] = crtc;
1813                 memcpy(crtcs, best_crtcs, n * sizeof(struct drm_fb_helper_crtc *));
1814                 score = my_score + drm_pick_crtcs(fb_helper, crtcs, modes, n + 1,
1815                                                   width, height);
1816                 if (score > best_score) {
1817                         best_score = score;
1818                         memcpy(best_crtcs, crtcs,
1819                                dev->mode_config.num_connector *
1820                                sizeof(struct drm_fb_helper_crtc *));
1821                 }
1822         }
1823 out:
1824         kfree(crtcs);
1825         return best_score;
1826 }
1827
1828 static void drm_setup_crtcs(struct drm_fb_helper *fb_helper)
1829 {
1830         struct drm_device *dev = fb_helper->dev;
1831         struct drm_fb_helper_crtc **crtcs;
1832         struct drm_display_mode **modes;
1833         struct drm_fb_offset *offsets;
1834         struct drm_mode_set *modeset;
1835         bool *enabled;
1836         int width, height;
1837         int i;
1838
1839         DRM_DEBUG_KMS("\n");
1840
1841         width = dev->mode_config.max_width;
1842         height = dev->mode_config.max_height;
1843
1844         crtcs = kcalloc(dev->mode_config.num_connector,
1845                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1846         modes = kcalloc(dev->mode_config.num_connector,
1847                         sizeof(struct drm_display_mode *), GFP_KERNEL);
1848         offsets = kcalloc(dev->mode_config.num_connector,
1849                           sizeof(struct drm_fb_offset), GFP_KERNEL);
1850         enabled = kcalloc(dev->mode_config.num_connector,
1851                           sizeof(bool), GFP_KERNEL);
1852         if (!crtcs || !modes || !enabled || !offsets) {
1853                 DRM_ERROR("Memory allocation failed\n");
1854                 goto out;
1855         }
1856
1857
1858         drm_enable_connectors(fb_helper, enabled);
1859
1860         if (!(fb_helper->funcs->initial_config &&
1861               fb_helper->funcs->initial_config(fb_helper, crtcs, modes,
1862                                                offsets,
1863                                                enabled, width, height))) {
1864                 memset(modes, 0, dev->mode_config.num_connector*sizeof(modes[0]));
1865                 memset(crtcs, 0, dev->mode_config.num_connector*sizeof(crtcs[0]));
1866                 memset(offsets, 0, dev->mode_config.num_connector*sizeof(offsets[0]));
1867
1868                 if (!drm_target_cloned(fb_helper, modes, offsets,
1869                                        enabled, width, height) &&
1870                     !drm_target_preferred(fb_helper, modes, offsets,
1871                                           enabled, width, height))
1872                         DRM_ERROR("Unable to find initial modes\n");
1873
1874                 DRM_DEBUG_KMS("picking CRTCs for %dx%d config\n",
1875                               width, height);
1876
1877                 drm_pick_crtcs(fb_helper, crtcs, modes, 0, width, height);
1878         }
1879
1880         /* need to set the modesets up here for use later */
1881         /* fill out the connector<->crtc mappings into the modesets */
1882         for (i = 0; i < fb_helper->crtc_count; i++) {
1883                 modeset = &fb_helper->crtc_info[i].mode_set;
1884                 modeset->num_connectors = 0;
1885                 modeset->fb = NULL;
1886         }
1887
1888         for (i = 0; i < fb_helper->connector_count; i++) {
1889                 struct drm_display_mode *mode = modes[i];
1890                 struct drm_fb_helper_crtc *fb_crtc = crtcs[i];
1891                 struct drm_fb_offset *offset = &offsets[i];
1892                 modeset = &fb_crtc->mode_set;
1893
1894                 if (mode && fb_crtc) {
1895                         DRM_DEBUG_KMS("desired mode %s set on crtc %d (%d,%d)\n",
1896                                       mode->name, fb_crtc->mode_set.crtc->base.id, offset->x, offset->y);
1897                         fb_crtc->desired_mode = mode;
1898                         fb_crtc->x = offset->x;
1899                         fb_crtc->y = offset->y;
1900                         if (modeset->mode)
1901                                 drm_mode_destroy(dev, modeset->mode);
1902                         modeset->mode = drm_mode_duplicate(dev,
1903                                                            fb_crtc->desired_mode);
1904                         modeset->connectors[modeset->num_connectors++] = fb_helper->connector_info[i]->connector;
1905                         modeset->fb = fb_helper->fb;
1906                         modeset->x = offset->x;
1907                         modeset->y = offset->y;
1908                 }
1909         }
1910
1911         /* Clear out any old modes if there are no more connected outputs. */
1912         for (i = 0; i < fb_helper->crtc_count; i++) {
1913                 modeset = &fb_helper->crtc_info[i].mode_set;
1914                 if (modeset->num_connectors == 0) {
1915                         BUG_ON(modeset->fb);
1916                         if (modeset->mode)
1917                                 drm_mode_destroy(dev, modeset->mode);
1918                         modeset->mode = NULL;
1919                 }
1920         }
1921 out:
1922         kfree(crtcs);
1923         kfree(modes);
1924         kfree(offsets);
1925         kfree(enabled);
1926 }
1927
1928 /**
1929  * drm_fb_helper_initial_config - setup a sane initial connector configuration
1930  * @fb_helper: fb_helper device struct
1931  * @bpp_sel: bpp value to use for the framebuffer configuration
1932  *
1933  * Scans the CRTCs and connectors and tries to put together an initial setup.
1934  * At the moment, this is a cloned configuration across all heads with
1935  * a new framebuffer object as the backing store.
1936  *
1937  * Note that this also registers the fbdev and so allows userspace to call into
1938  * the driver through the fbdev interfaces.
1939  *
1940  * This function will call down into the ->fb_probe callback to let
1941  * the driver allocate and initialize the fbdev info structure and the drm
1942  * framebuffer used to back the fbdev. drm_fb_helper_fill_var() and
1943  * drm_fb_helper_fill_fix() are provided as helpers to setup simple default
1944  * values for the fbdev info structure.
1945  *
1946  * RETURNS:
1947  * Zero if everything went ok, nonzero otherwise.
1948  */
1949 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel)
1950 {
1951         struct drm_device *dev = fb_helper->dev;
1952         int count = 0;
1953
1954         mutex_lock(&dev->mode_config.mutex);
1955         count = drm_fb_helper_probe_connector_modes(fb_helper,
1956                                                     dev->mode_config.max_width,
1957                                                     dev->mode_config.max_height);
1958         mutex_unlock(&dev->mode_config.mutex);
1959         /*
1960          * we shouldn't end up with no modes here.
1961          */
1962         if (count == 0)
1963                 dev_info(fb_helper->dev->dev, "No connectors reported connected with modes\n");
1964
1965         drm_setup_crtcs(fb_helper);
1966
1967         return drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
1968 }
1969 EXPORT_SYMBOL(drm_fb_helper_initial_config);
1970
1971 /**
1972  * drm_fb_helper_hotplug_event - respond to a hotplug notification by
1973  *                               probing all the outputs attached to the fb
1974  * @fb_helper: the drm_fb_helper
1975  *
1976  * Scan the connectors attached to the fb_helper and try to put together a
1977  * setup after *notification of a change in output configuration.
1978  *
1979  * Called at runtime, takes the mode config locks to be able to check/change the
1980  * modeset configuration. Must be run from process context (which usually means
1981  * either the output polling work or a work item launched from the driver's
1982  * hotplug interrupt).
1983  *
1984  * Note that drivers may call this even before calling
1985  * drm_fb_helper_initial_config but only aftert drm_fb_helper_init. This allows
1986  * for a race-free fbcon setup and will make sure that the fbdev emulation will
1987  * not miss any hotplug events.
1988  *
1989  * RETURNS:
1990  * 0 on success and a non-zero error code otherwise.
1991  */
1992 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
1993 {
1994         struct drm_device *dev = fb_helper->dev;
1995         u32 max_width, max_height;
1996
1997         mutex_lock(&fb_helper->dev->mode_config.mutex);
1998         if (!fb_helper->fb || !drm_fb_helper_is_bound(fb_helper)) {
1999                 fb_helper->delayed_hotplug = true;
2000                 mutex_unlock(&fb_helper->dev->mode_config.mutex);
2001                 return 0;
2002         }
2003         DRM_DEBUG_KMS("\n");
2004
2005         max_width = fb_helper->fb->width;
2006         max_height = fb_helper->fb->height;
2007
2008         drm_fb_helper_probe_connector_modes(fb_helper, max_width, max_height);
2009         mutex_unlock(&fb_helper->dev->mode_config.mutex);
2010
2011         drm_modeset_lock_all(dev);
2012         drm_setup_crtcs(fb_helper);
2013         drm_modeset_unlock_all(dev);
2014         drm_fb_helper_set_par(fb_helper->fbdev);
2015
2016         return 0;
2017 }
2018 EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
2019
2020 /* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
2021  * but the module doesn't depend on any fb console symbols.  At least
2022  * attempt to load fbcon to avoid leaving the system without a usable console.
2023  */
2024 #if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT)
2025 static int __init drm_fb_helper_modinit(void)
2026 {
2027         const char *name = "fbcon";
2028         struct module *fbcon;
2029
2030         mutex_lock(&module_mutex);
2031         fbcon = find_module(name);
2032         mutex_unlock(&module_mutex);
2033
2034         if (!fbcon)
2035                 request_module_nowait(name);
2036         return 0;
2037 }
2038
2039 module_init(drm_fb_helper_modinit);
2040 #endif