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 <[email protected]>
   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 <[email protected]>
  28  *      Jesse Barnes <[email protected]>
  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  * Since this is part of the initial setup before the fbdev is published, no
  93  * locking is required.
  94  */
  95 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
  96 {
  97         struct drm_device *dev = fb_helper->dev;
  98         struct drm_connector *connector;
  99         int i;
 100
 101         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 102                 struct drm_fb_helper_connector *fb_helper_connector;
 103
 104                 fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
 105                 if (!fb_helper_connector)
 106                         goto fail;
 107
 108                 fb_helper_connector->connector = connector;
 109                 fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
 110         }
 111         return 0;
 112 fail:
 113         for (i = 0; i < fb_helper->connector_count; i++) {
 114                 kfree(fb_helper->connector_info[i]);
 115                 fb_helper->connector_info[i] = NULL;
 116         }
 117         fb_helper->connector_count = 0;
 118         return -ENOMEM;
 119 }
 120 EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors);
 121
 122 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector)
 123 {
 124         struct drm_fb_helper_connector **temp;
 125         struct drm_fb_helper_connector *fb_helper_connector;
 126
 127         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
 128         if (fb_helper->connector_count + 1 > fb_helper->connector_info_alloc_count) {
 129                 temp = krealloc(fb_helper->connector_info, sizeof(struct drm_fb_helper_connector *) * (fb_helper->connector_count + 1), GFP_KERNEL);
 130                 if (!temp)
 131                         return -ENOMEM;
 132
 133                 fb_helper->connector_info_alloc_count = fb_helper->connector_count + 1;
 134                 fb_helper->connector_info = temp;
 135         }
 136
 137
 138         fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
 139         if (!fb_helper_connector)
 140                 return -ENOMEM;
 141
 142         fb_helper_connector->connector = connector;
 143         fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
 144         return 0;
 145 }
 146 EXPORT_SYMBOL(drm_fb_helper_add_one_connector);
 147
 148 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 149                                        struct drm_connector *connector)
 150 {
 151         struct drm_fb_helper_connector *fb_helper_connector;
 152         int i, j;
 153
 154         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
 155
 156         for (i = 0; i < fb_helper->connector_count; i++) {
 157                 if (fb_helper->connector_info[i]->connector == connector)
 158                         break;
 159         }
 160
 161         if (i == fb_helper->connector_count)
 162                 return -EINVAL;
 163         fb_helper_connector = fb_helper->connector_info[i];
 164
 165         for (j = i + 1; j < fb_helper->connector_count; j++) {
 166                 fb_helper->connector_info[j - 1] = fb_helper->connector_info[j];
 167         }
 168         fb_helper->connector_count--;
 169         kfree(fb_helper_connector);
 170         return 0;
 171 }
 172 EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
 173
 174 static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
 175 {
 176         uint16_t *r_base, *g_base, *b_base;
 177         int i;
 178
 179         if (helper->funcs->gamma_get == NULL)
 180                 return;
 181
 182         r_base = crtc->gamma_store;
 183         g_base = r_base + crtc->gamma_size;
 184         b_base = g_base + crtc->gamma_size;
 185
 186         for (i = 0; i < crtc->gamma_size; i++)
 187                 helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
 188 }
 189
 190 static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
 191 {
 192         uint16_t *r_base, *g_base, *b_base;
 193
 194         if (crtc->funcs->gamma_set == NULL)
 195                 return;
 196
 197         r_base = crtc->gamma_store;
 198         g_base = r_base + crtc->gamma_size;
 199         b_base = g_base + crtc->gamma_size;
 200
 201         crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, 0, crtc->gamma_size);
 202 }
 203
 204 /**
 205  * drm_fb_helper_debug_enter - implementation for ->fb_debug_enter
 206  * @info: fbdev registered by the helper
 207  */
 208 int drm_fb_helper_debug_enter(struct fb_info *info)
 209 {
 210         struct drm_fb_helper *helper = info->par;
 211         struct drm_crtc_helper_funcs *funcs;
 212         int i;
 213
 214         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 215                 for (i = 0; i < helper->crtc_count; i++) {
 216                         struct drm_mode_set *mode_set =
 217                                 &helper->crtc_info[i].mode_set;
 218
 219                         if (!mode_set->crtc->enabled)
 220                                 continue;
 221
 222                         funcs = mode_set->crtc->helper_private;
 223                         drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
 224                         funcs->mode_set_base_atomic(mode_set->crtc,
 225                                                     mode_set->fb,
 226                                                     mode_set->x,
 227                                                     mode_set->y,
 228                                                     ENTER_ATOMIC_MODE_SET);
 229                 }
 230         }
 231
 232         return 0;
 233 }
 234 EXPORT_SYMBOL(drm_fb_helper_debug_enter);
 235
 236 /* Find the real fb for a given fb helper CRTC */
 237 static struct drm_framebuffer *drm_mode_config_fb(struct drm_crtc *crtc)
 238 {
 239         struct drm_device *dev = crtc->dev;
 240         struct drm_crtc *c;
 241
 242         list_for_each_entry(c, &dev->mode_config.crtc_list, head) {
 243                 if (crtc->base.id == c->base.id)
 244                         return c->primary->fb;
 245         }
 246
 247         return NULL;
 248 }
 249
 250 /**
 251  * drm_fb_helper_debug_leave - implementation for ->fb_debug_leave
 252  * @info: fbdev registered by the helper
 253  */
 254 int drm_fb_helper_debug_leave(struct fb_info *info)
 255 {
 256         struct drm_fb_helper *helper = info->par;
 257         struct drm_crtc *crtc;
 258         struct drm_crtc_helper_funcs *funcs;
 259         struct drm_framebuffer *fb;
 260         int i;
 261
 262         for (i = 0; i < helper->crtc_count; i++) {
 263                 struct drm_mode_set *mode_set = &helper->crtc_info[i].mode_set;
 264                 crtc = mode_set->crtc;
 265                 funcs = crtc->helper_private;
 266                 fb = drm_mode_config_fb(crtc);
 267
 268                 if (!crtc->enabled)
 269                         continue;
 270
 271                 if (!fb) {
 272                         DRM_ERROR("no fb to restore??\n");
 273                         continue;
 274                 }
 275
 276                 drm_fb_helper_restore_lut_atomic(mode_set->crtc);
 277                 funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
 278                                             crtc->y, LEAVE_ATOMIC_MODE_SET);
 279         }
 280
 281         return 0;
 282 }
 283 EXPORT_SYMBOL(drm_fb_helper_debug_leave);
 284
 285 static bool restore_fbdev_mode(struct drm_fb_helper *fb_helper)
 286 {
 287         struct drm_device *dev = fb_helper->dev;
 288         struct drm_plane *plane;
 289         bool error = false;
 290         int i;
 291
 292         drm_warn_on_modeset_not_all_locked(dev);
 293
 294         list_for_each_entry(plane, &dev->mode_config.plane_list, head) {
 295                 if (plane->type != DRM_PLANE_TYPE_PRIMARY)
 296                         drm_plane_force_disable(plane);
 297
 298                 if (dev->mode_config.rotation_property) {
 299                         drm_mode_plane_set_obj_prop(plane,
 300                                                     dev->mode_config.rotation_property,
 301                                                     BIT(DRM_ROTATE_0));
 302                 }
 303         }
 304
 305         for (i = 0; i < fb_helper->crtc_count; i++) {
 306                 struct drm_mode_set *mode_set = &fb_helper->crtc_info[i].mode_set;
 307                 struct drm_crtc *crtc = mode_set->crtc;
 308                 int ret;
 309
 310                 if (crtc->funcs->cursor_set) {
 311                         ret = crtc->funcs->cursor_set(crtc, NULL, 0, 0, 0);
 312                         if (ret)
 313                                 error = true;
 314                 }
 315
 316                 ret = drm_mode_set_config_internal(mode_set);
 317                 if (ret)
 318                         error = true;
 319         }
 320         return error;
 321 }
 322 /**
 323  * drm_fb_helper_restore_fbdev_mode - restore fbdev configuration
 324  * @fb_helper: fbcon to restore
 325  *
 326  * This should be called from driver's drm ->lastclose callback
 327  * when implementing an fbcon on top of kms using this helper. This ensures that
 328  * the user isn't greeted with a black screen when e.g. X dies.
 329  *
 330  * Use this variant if you need to bypass locking (panic), or already
 331  * hold all modeset locks.  Otherwise use drm_fb_helper_restore_fbdev_mode_unlocked()
 332  */
 333 static bool drm_fb_helper_restore_fbdev_mode(struct drm_fb_helper *fb_helper)
 334 {
 335         return restore_fbdev_mode(fb_helper);
 336 }
 337
 338 /**
 339  * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration
 340  * @fb_helper: fbcon to restore
 341  *
 342  * This should be called from driver's drm ->lastclose callback
 343  * when implementing an fbcon on top of kms using this helper. This ensures that
 344  * the user isn't greeted with a black screen when e.g. X dies.
 345  */
 346 bool drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
 347 {
 348         struct drm_device *dev = fb_helper->dev;
 349         bool ret;
 350         drm_modeset_lock_all(dev);
 351         ret = restore_fbdev_mode(fb_helper);
 352         drm_modeset_unlock_all(dev);
 353         return ret;
 354 }
 355 EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked);
 356
 357 /*
 358  * restore fbcon display for all kms driver's using this helper, used for sysrq
 359  * and panic handling.
 360  */
 361 static bool drm_fb_helper_force_kernel_mode(void)
 362 {
 363         bool ret, error = false;
 364         struct drm_fb_helper *helper;
 365
 366         if (list_empty(&kernel_fb_helper_list))
 367                 return false;
 368
 369         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 370                 struct drm_device *dev = helper->dev;
 371
 372                 if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
 373                         continue;
 374
 375                 /*
 376                  * NOTE: Use trylock mode to avoid deadlocks and sleeping in
 377                  * panic context.
 378                  */
 379                 if (__drm_modeset_lock_all(dev, true) != 0) {
 380                         error = true;
 381                         continue;
 382                 }
 383
 384                 ret = drm_fb_helper_restore_fbdev_mode(helper);
 385                 if (ret)
 386                         error = true;
 387
 388                 drm_modeset_unlock_all(dev);
 389         }
 390         return error;
 391 }
 392
 393 static int drm_fb_helper_panic(struct notifier_block *n, unsigned long ununsed,
 394                         void *panic_str)
 395 {
 396         /*
 397          * It's a waste of time and effort to switch back to text console
 398          * if the kernel should reboot before panic messages can be seen.
 399          */
 400         if (panic_timeout < 0)
 401                 return 0;
 402
 403         pr_err("panic occurred, switching back to text console\n");
 404         return drm_fb_helper_force_kernel_mode();
 405 }
 406
 407 static struct notifier_block paniced = {
 408         .notifier_call = drm_fb_helper_panic,
 409 };
 410
 411 static bool drm_fb_helper_is_bound(struct drm_fb_helper *fb_helper)
 412 {
 413         struct drm_device *dev = fb_helper->dev;
 414         struct drm_crtc *crtc;
 415         int bound = 0, crtcs_bound = 0;
 416
 417         /* Sometimes user space wants everything disabled, so don't steal the
 418          * display if there's a master. */
 419         if (dev->primary->master)
 420                 return false;
 421
 422         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 423                 if (crtc->primary->fb)
 424                         crtcs_bound++;
 425                 if (crtc->primary->fb == fb_helper->fb)
 426                         bound++;
 427         }
 428
 429         if (bound < crtcs_bound)
 430                 return false;
 431
 432         return true;
 433 }
 434
 435 #ifdef CONFIG_MAGIC_SYSRQ
 436 static void drm_fb_helper_restore_work_fn(struct work_struct *ignored)
 437 {
 438         bool ret;
 439         ret = drm_fb_helper_force_kernel_mode();
 440         if (ret == true)
 441                 DRM_ERROR("Failed to restore crtc configuration\n");
 442 }
 443 static DECLARE_WORK(drm_fb_helper_restore_work, drm_fb_helper_restore_work_fn);
 444
 445 static void drm_fb_helper_sysrq(int dummy1)
 446 {
 447         schedule_work(&drm_fb_helper_restore_work);
 448 }
 449
 450 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = {
 451         .handler = drm_fb_helper_sysrq,
 452         .help_msg = "force-fb(V)",
 453         .action_msg = "Restore framebuffer console",
 454 };
 455 #else
 456 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { };
 457 #endif
 458
 459 static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
 460 {
 461         struct drm_fb_helper *fb_helper = info->par;
 462         struct drm_device *dev = fb_helper->dev;
 463         struct drm_crtc *crtc;
 464         struct drm_connector *connector;
 465         int i, j;
 466
 467         /*
 468          * fbdev->blank can be called from irq context in case of a panic.
 469          * Since we already have our own special panic handler which will
 470          * restore the fbdev console mode completely, just bail out early.
 471          */
 472         if (oops_in_progress)
 473                 return;
 474
 475         /*
 476          * For each CRTC in this fb, turn the connectors on/off.
 477          */
 478         drm_modeset_lock_all(dev);
 479         if (!drm_fb_helper_is_bound(fb_helper)) {
 480                 drm_modeset_unlock_all(dev);
 481                 return;
 482         }
 483
 484         for (i = 0; i < fb_helper->crtc_count; i++) {
 485                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
 486
 487                 if (!crtc->enabled)
 488                         continue;
 489
 490                 /* Walk the connectors & encoders on this fb turning them on/off */
 491                 for (j = 0; j < fb_helper->connector_count; j++) {
 492                         connector = fb_helper->connector_info[j]->connector;
 493                         connector->funcs->dpms(connector, dpms_mode);
 494                         drm_object_property_set_value(&connector->base,
 495                                 dev->mode_config.dpms_property, dpms_mode);
 496                 }
 497         }
 498         drm_modeset_unlock_all(dev);
 499 }
 500
 501 /**
 502  * drm_fb_helper_blank - implementation for ->fb_blank
 503  * @blank: desired blanking state
 504  * @info: fbdev registered by the helper
 505  */
 506 int drm_fb_helper_blank(int blank, struct fb_info *info)
 507 {
 508         switch (blank) {
 509         /* Display: On; HSync: On, VSync: On */
 510         case FB_BLANK_UNBLANK:
 511                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON);
 512                 break;
 513         /* Display: Off; HSync: On, VSync: On */
 514         case FB_BLANK_NORMAL:
 515                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 516                 break;
 517         /* Display: Off; HSync: Off, VSync: On */
 518         case FB_BLANK_HSYNC_SUSPEND:
 519                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 520                 break;
 521         /* Display: Off; HSync: On, VSync: Off */
 522         case FB_BLANK_VSYNC_SUSPEND:
 523                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND);
 524                 break;
 525         /* Display: Off; HSync: Off, VSync: Off */
 526         case FB_BLANK_POWERDOWN:
 527                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF);
 528                 break;
 529         }
 530         return 0;
 531 }
 532 EXPORT_SYMBOL(drm_fb_helper_blank);
 533
 534 static void drm_fb_helper_crtc_free(struct drm_fb_helper *helper)
 535 {
 536         int i;
 537
 538         for (i = 0; i < helper->connector_count; i++)
 539                 kfree(helper->connector_info[i]);
 540         kfree(helper->connector_info);
 541         for (i = 0; i < helper->crtc_count; i++) {
 542                 kfree(helper->crtc_info[i].mode_set.connectors);
 543                 if (helper->crtc_info[i].mode_set.mode)
 544                         drm_mode_destroy(helper->dev, helper->crtc_info[i].mode_set.mode);
 545         }
 546         kfree(helper->crtc_info);
 547 }
 548
 549 /**
 550  * drm_fb_helper_prepare - setup a drm_fb_helper structure
 551  * @dev: DRM device
 552  * @helper: driver-allocated fbdev helper structure to set up
 553  * @funcs: pointer to structure of functions associate with this helper
 554  *
 555  * Sets up the bare minimum to make the framebuffer helper usable. This is
 556  * useful to implement race-free initialization of the polling helpers.
 557  */
 558 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
 559                            const struct drm_fb_helper_funcs *funcs)
 560 {
 561         INIT_LIST_HEAD(&helper->kernel_fb_list);
 562         helper->funcs = funcs;
 563         helper->dev = dev;
 564 }
 565 EXPORT_SYMBOL(drm_fb_helper_prepare);
 566
 567 /**
 568  * drm_fb_helper_init - initialize a drm_fb_helper structure
 569  * @dev: drm device
 570  * @fb_helper: driver-allocated fbdev helper structure to initialize
 571  * @crtc_count: maximum number of crtcs to support in this fbdev emulation
 572  * @max_conn_count: max connector count
 573  *
 574  * This allocates the structures for the fbdev helper with the given limits.
 575  * Note that this won't yet touch the hardware (through the driver interfaces)
 576  * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
 577  * to allow driver writes more control over the exact init sequence.
 578  *
 579  * Drivers must call drm_fb_helper_prepare() before calling this function.
 580  *
 581  * RETURNS:
 582  * Zero if everything went ok, nonzero otherwise.
 583  */
 584 int drm_fb_helper_init(struct drm_device *dev,
 585                        struct drm_fb_helper *fb_helper,
 586                        int crtc_count, int max_conn_count)
 587 {
 588         struct drm_crtc *crtc;
 589         int i;
 590
 591         if (!max_conn_count)
 592                 return -EINVAL;
 593
 594         fb_helper->crtc_info = kcalloc(crtc_count, sizeof(struct drm_fb_helper_crtc), GFP_KERNEL);
 595         if (!fb_helper->crtc_info)
 596                 return -ENOMEM;
 597
 598         fb_helper->crtc_count = crtc_count;
 599         fb_helper->connector_info = kcalloc(dev->mode_config.num_connector, sizeof(struct drm_fb_helper_connector *), GFP_KERNEL);
 600         if (!fb_helper->connector_info) {
 601                 kfree(fb_helper->crtc_info);
 602                 return -ENOMEM;
 603         }
 604         fb_helper->connector_info_alloc_count = dev->mode_config.num_connector;
 605         fb_helper->connector_count = 0;
 606
 607         for (i = 0; i < crtc_count; i++) {
 608                 fb_helper->crtc_info[i].mode_set.connectors =
 609                         kcalloc(max_conn_count,
 610                                 sizeof(struct drm_connector *),
 611                                 GFP_KERNEL);
 612
 613                 if (!fb_helper->crtc_info[i].mode_set.connectors)
 614                         goto out_free;
 615                 fb_helper->crtc_info[i].mode_set.num_connectors = 0;
 616         }
 617
 618         i = 0;
 619         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 620                 fb_helper->crtc_info[i].mode_set.crtc = crtc;
 621                 i++;
 622         }
 623
 624         return 0;
 625 out_free:
 626         drm_fb_helper_crtc_free(fb_helper);
 627         return -ENOMEM;
 628 }
 629 EXPORT_SYMBOL(drm_fb_helper_init);
 630
 631 void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
 632 {
 633         if (!list_empty(&fb_helper->kernel_fb_list)) {
 634                 list_del(&fb_helper->kernel_fb_list);
 635                 if (list_empty(&kernel_fb_helper_list)) {
 636                         pr_info("drm: unregistered panic notifier\n");
 637                         atomic_notifier_chain_unregister(&panic_notifier_list,
 638                                                          &paniced);
 639                         unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
 640                 }
 641         }
 642
 643         drm_fb_helper_crtc_free(fb_helper);
 644
 645 }
 646 EXPORT_SYMBOL(drm_fb_helper_fini);
 647
 648 static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
 649                      u16 blue, u16 regno, struct fb_info *info)
 650 {
 651         struct drm_fb_helper *fb_helper = info->par;
 652         struct drm_framebuffer *fb = fb_helper->fb;
 653         int pindex;
 654
 655         if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
 656                 u32 *palette;
 657                 u32 value;
 658                 /* place color in psuedopalette */
 659                 if (regno > 16)
 660                         return -EINVAL;
 661                 palette = (u32 *)info->pseudo_palette;
 662                 red >>= (16 - info->var.red.length);
 663                 green >>= (16 - info->var.green.length);
 664                 blue >>= (16 - info->var.blue.length);
 665                 value = (red << info->var.red.offset) |
 666                         (green << info->var.green.offset) |
 667                         (blue << info->var.blue.offset);
 668                 if (info->var.transp.length > 0) {
 669                         u32 mask = (1 << info->var.transp.length) - 1;
 670                         mask <<= info->var.transp.offset;
 671                         value |= mask;
 672                 }
 673                 palette[regno] = value;
 674                 return 0;
 675         }
 676
 677         /*
 678          * The driver really shouldn't advertise pseudo/directcolor
 679          * visuals if it can't deal with the palette.
 680          */
 681         if (WARN_ON(!fb_helper->funcs->gamma_set ||
 682                     !fb_helper->funcs->gamma_get))
 683                 return -EINVAL;
 684
 685         pindex = regno;
 686
 687         if (fb->bits_per_pixel == 16) {
 688                 pindex = regno << 3;
 689
 690                 if (fb->depth == 16 && regno > 63)
 691                         return -EINVAL;
 692                 if (fb->depth == 15 && regno > 31)
 693                         return -EINVAL;
 694
 695                 if (fb->depth == 16) {
 696                         u16 r, g, b;
 697                         int i;
 698                         if (regno < 32) {
 699                                 for (i = 0; i < 8; i++)
 700                                         fb_helper->funcs->gamma_set(crtc, red,
 701                                                 green, blue, pindex + i);
 702                         }
 703
 704                         fb_helper->funcs->gamma_get(crtc, &r,
 705                                                     &g, &b,
 706                                                     pindex >> 1);
 707
 708                         for (i = 0; i < 4; i++)
 709                                 fb_helper->funcs->gamma_set(crtc, r,
 710                                                             green, b,
 711                                                             (pindex >> 1) + i);
 712                 }
 713         }
 714
 715         if (fb->depth != 16)
 716                 fb_helper->funcs->gamma_set(crtc, red, green, blue, pindex);
 717         return 0;
 718 }
 719
 720 /**
 721  * drm_fb_helper_setcmap - implementation for ->fb_setcmap
 722  * @cmap: cmap to set
 723  * @info: fbdev registered by the helper
 724  */
 725 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
 726 {
 727         struct drm_fb_helper *fb_helper = info->par;
 728         struct drm_device *dev = fb_helper->dev;
 729         struct drm_crtc_helper_funcs *crtc_funcs;
 730         u16 *red, *green, *blue, *transp;
 731         struct drm_crtc *crtc;
 732         int i, j, rc = 0;
 733         int start;
 734
 735         drm_modeset_lock_all(dev);
 736         if (!drm_fb_helper_is_bound(fb_helper)) {
 737                 drm_modeset_unlock_all(dev);
 738                 return -EBUSY;
 739         }
 740
 741         for (i = 0; i < fb_helper->crtc_count; i++) {
 742                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
 743                 crtc_funcs = crtc->helper_private;
 744
 745                 red = cmap->red;
 746                 green = cmap->green;
 747                 blue = cmap->blue;
 748                 transp = cmap->transp;
 749                 start = cmap->start;
 750
 751                 for (j = 0; j < cmap->len; j++) {
 752                         u16 hred, hgreen, hblue, htransp = 0xffff;
 753
 754                         hred = *red++;
 755                         hgreen = *green++;
 756                         hblue = *blue++;
 757
 758                         if (transp)
 759                                 htransp = *transp++;
 760
 761                         rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
 762                         if (rc)
 763                                 goto out;
 764                 }
 765                 if (crtc_funcs->load_lut)
 766                         crtc_funcs->load_lut(crtc);
 767         }
 768  out:
 769         drm_modeset_unlock_all(dev);
 770         return rc;
 771 }
 772 EXPORT_SYMBOL(drm_fb_helper_setcmap);
 773
 774 /**
 775  * drm_fb_helper_check_var - implementation for ->fb_check_var
 776  * @var: screeninfo to check
 777  * @info: fbdev registered by the helper
 778  */
 779 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 780                             struct fb_info *info)
 781 {
 782         struct drm_fb_helper *fb_helper = info->par;
 783         struct drm_framebuffer *fb = fb_helper->fb;
 784         int depth;
 785
 786         if (var->pixclock != 0 || in_dbg_master())
 787                 return -EINVAL;
 788
 789         /* Need to resize the fb object !!! */
 790         if (var->bits_per_pixel > fb->bits_per_pixel ||
 791             var->xres > fb->width || var->yres > fb->height ||
 792             var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
 793                 DRM_DEBUG("fb userspace requested width/height/bpp is greater than current fb "
 794                           "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
 795                           var->xres, var->yres, var->bits_per_pixel,
 796                           var->xres_virtual, var->yres_virtual,
 797                           fb->width, fb->height, fb->bits_per_pixel);
 798                 return -EINVAL;
 799         }
 800
 801         switch (var->bits_per_pixel) {
 802         case 16:
 803                 depth = (var->green.length == 6) ? 16 : 15;
 804                 break;
 805         case 32:
 806                 depth = (var->transp.length > 0) ? 32 : 24;
 807                 break;
 808         default:
 809                 depth = var->bits_per_pixel;
 810                 break;
 811         }
 812
 813         switch (depth) {
 814         case 8:
 815                 var->red.offset = 0;
 816                 var->green.offset = 0;
 817                 var->blue.offset = 0;
 818                 var->red.length = 8;
 819                 var->green.length = 8;
 820                 var->blue.length = 8;
 821                 var->transp.length = 0;
 822                 var->transp.offset = 0;
 823                 break;
 824         case 15:
 825                 var->red.offset = 10;
 826                 var->green.offset = 5;
 827                 var->blue.offset = 0;
 828                 var->red.length = 5;
 829                 var->green.length = 5;
 830                 var->blue.length = 5;
 831                 var->transp.length = 1;
 832                 var->transp.offset = 15;
 833                 break;
 834         case 16:
 835                 var->red.offset = 11;
 836                 var->green.offset = 5;
 837                 var->blue.offset = 0;
 838                 var->red.length = 5;
 839                 var->green.length = 6;
 840                 var->blue.length = 5;
 841                 var->transp.length = 0;
 842                 var->transp.offset = 0;
 843                 break;
 844         case 24:
 845                 var->red.offset = 16;
 846                 var->green.offset = 8;
 847                 var->blue.offset = 0;
 848                 var->red.length = 8;
 849                 var->green.length = 8;
 850                 var->blue.length = 8;
 851                 var->transp.length = 0;
 852                 var->transp.offset = 0;
 853                 break;
 854         case 32:
 855                 var->red.offset = 16;
 856                 var->green.offset = 8;
 857                 var->blue.offset = 0;
 858                 var->red.length = 8;
 859                 var->green.length = 8;
 860                 var->blue.length = 8;
 861                 var->transp.length = 8;
 862                 var->transp.offset = 24;
 863                 break;
 864         default:
 865                 return -EINVAL;
 866         }
 867         return 0;
 868 }
 869 EXPORT_SYMBOL(drm_fb_helper_check_var);
 870
 871 /**
 872  * drm_fb_helper_set_par - implementation for ->fb_set_par
 873  * @info: fbdev registered by the helper
 874  *
 875  * This will let fbcon do the mode init and is called at initialization time by
 876  * the fbdev core when registering the driver, and later on through the hotplug
 877  * callback.
 878  */
 879 int drm_fb_helper_set_par(struct fb_info *info)
 880 {
 881         struct drm_fb_helper *fb_helper = info->par;
 882         struct fb_var_screeninfo *var = &info->var;
 883
 884         if (var->pixclock != 0) {
 885                 DRM_ERROR("PIXEL CLOCK SET\n");
 886                 return -EINVAL;
 887         }
 888
 889         drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper);
 890
 891         if (fb_helper->delayed_hotplug) {
 892                 fb_helper->delayed_hotplug = false;
 893                 drm_fb_helper_hotplug_event(fb_helper);
 894         }
 895         return 0;
 896 }
 897 EXPORT_SYMBOL(drm_fb_helper_set_par);
 898
 899 /**
 900  * drm_fb_helper_pan_display - implementation for ->fb_pan_display
 901  * @var: updated screen information
 902  * @info: fbdev registered by the helper
 903  */
 904 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
 905                               struct fb_info *info)
 906 {
 907         struct drm_fb_helper *fb_helper = info->par;
 908         struct drm_device *dev = fb_helper->dev;
 909         struct drm_mode_set *modeset;
 910         int ret = 0;
 911         int i;
 912
 913         drm_modeset_lock_all(dev);
 914         if (!drm_fb_helper_is_bound(fb_helper)) {
 915                 drm_modeset_unlock_all(dev);
 916                 return -EBUSY;
 917         }
 918
 919         for (i = 0; i < fb_helper->crtc_count; i++) {
 920                 modeset = &fb_helper->crtc_info[i].mode_set;
 921
 922                 modeset->x = var->xoffset;
 923                 modeset->y = var->yoffset;
 924
 925                 if (modeset->num_connectors) {
 926                         ret = drm_mode_set_config_internal(modeset);
 927                         if (!ret) {
 928                                 info->var.xoffset = var->xoffset;
 929                                 info->var.yoffset = var->yoffset;
 930                         }
 931                 }
 932         }
 933         drm_modeset_unlock_all(dev);
 934         return ret;
 935 }
 936 EXPORT_SYMBOL(drm_fb_helper_pan_display);
 937
 938 /*
 939  * Allocates the backing storage and sets up the fbdev info structure through
 940  * the ->fb_probe callback and then registers the fbdev and sets up the panic
 941  * notifier.
 942  */
 943 static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
 944                                          int preferred_bpp)
 945 {
 946         int ret = 0;
 947         int crtc_count = 0;
 948         int i;
 949         struct fb_info *info;
 950         struct drm_fb_helper_surface_size sizes;
 951         int gamma_size = 0;
 952
 953         memset(&sizes, 0, sizeof(struct drm_fb_helper_surface_size));
 954         sizes.surface_depth = 24;
 955         sizes.surface_bpp = 32;
 956         sizes.fb_width = (unsigned)-1;
 957         sizes.fb_height = (unsigned)-1;
 958
 959         /* if driver picks 8 or 16 by default use that
 960            for both depth/bpp */
 961         if (preferred_bpp != sizes.surface_bpp)
 962                 sizes.surface_depth = sizes.surface_bpp = preferred_bpp;
 963
 964         /* first up get a count of crtcs now in use and new min/maxes width/heights */
 965         for (i = 0; i < fb_helper->connector_count; i++) {
 966                 struct drm_fb_helper_connector *fb_helper_conn = fb_helper->connector_info[i];
 967                 struct drm_cmdline_mode *cmdline_mode;
 968
 969                 cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
 970
 971                 if (cmdline_mode->bpp_specified) {
 972                         switch (cmdline_mode->bpp) {
 973                         case 8:
 974                                 sizes.surface_depth = sizes.surface_bpp = 8;
 975                                 break;
 976                         case 15:
 977                                 sizes.surface_depth = 15;
 978                                 sizes.surface_bpp = 16;
 979                                 break;
 980                         case 16:
 981                                 sizes.surface_depth = sizes.surface_bpp = 16;
 982                                 break;
 983                         case 24:
 984                                 sizes.surface_depth = sizes.surface_bpp = 24;
 985                                 break;
 986                         case 32:
 987                                 sizes.surface_depth = 24;
 988                                 sizes.surface_bpp = 32;
 989                                 break;
 990                         }
 991                         break;
 992                 }
 993         }
 994
 995         crtc_count = 0;
 996         for (i = 0; i < fb_helper->crtc_count; i++) {
 997                 struct drm_display_mode *desired_mode;
 998                 desired_mode = fb_helper->crtc_info[i].desired_mode;
 999
1000                 if (desired_mode) {
1001                         if (gamma_size == 0)
1002                                 gamma_size = fb_helper->crtc_info[i].mode_set.crtc->gamma_size;
1003                         if (desired_mode->hdisplay < sizes.fb_width)
1004                                 sizes.fb_width = desired_mode->hdisplay;
1005                         if (desired_mode->vdisplay < sizes.fb_height)
1006                                 sizes.fb_height = desired_mode->vdisplay;
1007                         if (desired_mode->hdisplay > sizes.surface_width)
1008                                 sizes.surface_width = desired_mode->hdisplay;
1009                         if (desired_mode->vdisplay > sizes.surface_height)
1010                                 sizes.surface_height = desired_mode->vdisplay;
1011                         crtc_count++;
1012                 }
1013         }
1014
1015         if (crtc_count == 0 || sizes.fb_width == -1 || sizes.fb_height == -1) {
1016                 /* hmm everyone went away - assume VGA cable just fell out
1017                    and will come back later. */
1018                 DRM_INFO("Cannot find any crtc or sizes - going 1024x768\n");
1019                 sizes.fb_width = sizes.surface_width = 1024;
1020                 sizes.fb_height = sizes.surface_height = 768;
1021         }
1022
1023         /* push down into drivers */
1024         ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);
1025         if (ret < 0)
1026                 return ret;
1027
1028         info = fb_helper->fbdev;
1029
1030         /*
1031          * Set the fb pointer - usually drm_setup_crtcs does this for hotplug
1032          * events, but at init time drm_setup_crtcs needs to be called before
1033          * the fb is allocated (since we need to figure out the desired size of
1034          * the fb before we can allocate it ...). Hence we need to fix things up
1035          * here again.
1036          */
1037         for (i = 0; i < fb_helper->crtc_count; i++)
1038                 if (fb_helper->crtc_info[i].mode_set.num_connectors)
1039                         fb_helper->crtc_info[i].mode_set.fb = fb_helper->fb;
1040
1041
1042         info->var.pixclock = 0;
1043         if (register_framebuffer(info) < 0)
1044                 return -EINVAL;
1045
1046         dev_info(fb_helper->dev->dev, "fb%d: %s frame buffer device\n",
1047                         info->node, info->fix.id);
1048
1049         /* Switch back to kernel console on panic */
1050         /* multi card linked list maybe */
1051         if (list_empty(&kernel_fb_helper_list)) {
1052                 dev_info(fb_helper->dev->dev, "registered panic notifier\n");
1053                 atomic_notifier_chain_register(&panic_notifier_list,
1054                                                &paniced);
1055                 register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
1056         }
1057
1058         list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
1059
1060         return 0;
1061 }
1062
1063 /**
1064  * drm_fb_helper_fill_fix - initializes fixed fbdev information
1065  * @info: fbdev registered by the helper
1066  * @pitch: desired pitch
1067  * @depth: desired depth
1068  *
1069  * Helper to fill in the fixed fbdev information useful for a non-accelerated
1070  * fbdev emulations. Drivers which support acceleration methods which impose
1071  * additional constraints need to set up their own limits.
1072  *
1073  * Drivers should call this (or their equivalent setup code) from their
1074  * ->fb_probe callback.
1075  */
1076 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
1077                             uint32_t depth)
1078 {
1079         info->fix.type = FB_TYPE_PACKED_PIXELS;
1080         info->fix.visual = depth == 8 ? FB_VISUAL_PSEUDOCOLOR :
1081                 FB_VISUAL_TRUECOLOR;
1082         info->fix.mmio_start = 0;
1083         info->fix.mmio_len = 0;
1084         info->fix.type_aux = 0;
1085         info->fix.xpanstep = 1; /* doing it in hw */
1086         info->fix.ypanstep = 1; /* doing it in hw */
1087         info->fix.ywrapstep = 0;
1088         info->fix.accel = FB_ACCEL_NONE;
1089
1090         info->fix.line_length = pitch;
1091         return;
1092 }
1093 EXPORT_SYMBOL(drm_fb_helper_fill_fix);
1094
1095 /**
1096  * drm_fb_helper_fill_var - initalizes variable fbdev information
1097  * @info: fbdev instance to set up
1098  * @fb_helper: fb helper instance to use as template
1099  * @fb_width: desired fb width
1100  * @fb_height: desired fb height
1101  *
1102  * Sets up the variable fbdev metainformation from the given fb helper instance
1103  * and the drm framebuffer allocated in fb_helper->fb.
1104  *
1105  * Drivers should call this (or their equivalent setup code) from their
1106  * ->fb_probe callback after having allocated the fbdev backing
1107  * storage framebuffer.
1108  */
1109 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
1110                             uint32_t fb_width, uint32_t fb_height)
1111 {
1112         struct drm_framebuffer *fb = fb_helper->fb;
1113         info->pseudo_palette = fb_helper->pseudo_palette;
1114         info->var.xres_virtual = fb->width;
1115         info->var.yres_virtual = fb->height;
1116         info->var.bits_per_pixel = fb->bits_per_pixel;
1117         info->var.accel_flags = FB_ACCELF_TEXT;
1118         info->var.xoffset = 0;
1119         info->var.yoffset = 0;
1120         info->var.activate = FB_ACTIVATE_NOW;
1121         info->var.height = -1;
1122         info->var.width = -1;
1123
1124         switch (fb->depth) {
1125         case 8:
1126                 info->var.red.offset = 0;
1127                 info->var.green.offset = 0;
1128                 info->var.blue.offset = 0;
1129                 info->var.red.length = 8; /* 8bit DAC */
1130                 info->var.green.length = 8;
1131                 info->var.blue.length = 8;
1132                 info->var.transp.offset = 0;
1133                 info->var.transp.length = 0;
1134                 break;
1135         case 15:
1136                 info->var.red.offset = 10;
1137                 info->var.green.offset = 5;
1138                 info->var.blue.offset = 0;
1139                 info->var.red.length = 5;
1140                 info->var.green.length = 5;
1141                 info->var.blue.length = 5;
1142                 info->var.transp.offset = 15;
1143                 info->var.transp.length = 1;
1144                 break;
1145         case 16:
1146                 info->var.red.offset = 11;
1147                 info->var.green.offset = 5;
1148                 info->var.blue.offset = 0;
1149                 info->var.red.length = 5;
1150                 info->var.green.length = 6;
1151                 info->var.blue.length = 5;
1152                 info->var.transp.offset = 0;
1153                 break;
1154         case 24:
1155                 info->var.red.offset = 16;
1156                 info->var.green.offset = 8;
1157                 info->var.blue.offset = 0;
1158                 info->var.red.length = 8;
1159                 info->var.green.length = 8;
1160                 info->var.blue.length = 8;
1161                 info->var.transp.offset = 0;
1162                 info->var.transp.length = 0;
1163                 break;
1164         case 32:
1165                 info->var.red.offset = 16;
1166                 info->var.green.offset = 8;
1167                 info->var.blue.offset = 0;
1168                 info->var.red.length = 8;
1169                 info->var.green.length = 8;
1170                 info->var.blue.length = 8;
1171                 info->var.transp.offset = 24;
1172                 info->var.transp.length = 8;
1173                 break;
1174         default:
1175                 break;
1176         }
1177
1178         info->var.xres = fb_width;
1179         info->var.yres = fb_height;
1180 }
1181 EXPORT_SYMBOL(drm_fb_helper_fill_var);
1182
1183 static int drm_fb_helper_probe_connector_modes(struct drm_fb_helper *fb_helper,
1184                                                uint32_t maxX,
1185                                                uint32_t maxY)
1186 {
1187         struct drm_connector *connector;
1188         int count = 0;
1189         int i;
1190
1191         for (i = 0; i < fb_helper->connector_count; i++) {
1192                 connector = fb_helper->connector_info[i]->connector;
1193                 count += connector->funcs->fill_modes(connector, maxX, maxY);
1194         }
1195
1196         return count;
1197 }
1198
1199 struct drm_display_mode *drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector, int width, int height)
1200 {
1201         struct drm_display_mode *mode;
1202
1203         list_for_each_entry(mode, &fb_connector->connector->modes, head) {
1204                 if (mode->hdisplay > width ||
1205                     mode->vdisplay > height)
1206                         continue;
1207                 if (mode->type & DRM_MODE_TYPE_PREFERRED)
1208                         return mode;
1209         }
1210         return NULL;
1211 }
1212 EXPORT_SYMBOL(drm_has_preferred_mode);
1213
1214 static bool drm_has_cmdline_mode(struct drm_fb_helper_connector *fb_connector)
1215 {
1216         return fb_connector->connector->cmdline_mode.specified;
1217 }
1218
1219 struct drm_display_mode *drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
1220                                                       int width, int height)
1221 {
1222         struct drm_cmdline_mode *cmdline_mode;
1223         struct drm_display_mode *mode = NULL;
1224         bool prefer_non_interlace;
1225
1226         cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1227         if (cmdline_mode->specified == false)
1228                 return mode;
1229
1230         /* attempt to find a matching mode in the list of modes
1231          *  we have gotten so far, if not add a CVT mode that conforms
1232          */
1233         if (cmdline_mode->rb || cmdline_mode->margins)
1234                 goto create_mode;
1235
1236         prefer_non_interlace = !cmdline_mode->interlace;
1237  again:
1238         list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1239                 /* check width/height */
1240                 if (mode->hdisplay != cmdline_mode->xres ||
1241                     mode->vdisplay != cmdline_mode->yres)
1242                         continue;
1243
1244                 if (cmdline_mode->refresh_specified) {
1245                         if (mode->vrefresh != cmdline_mode->refresh)
1246                                 continue;
1247                 }
1248
1249                 if (cmdline_mode->interlace) {
1250                         if (!(mode->flags & DRM_MODE_FLAG_INTERLACE))
1251                                 continue;
1252                 } else if (prefer_non_interlace) {
1253                         if (mode->flags & DRM_MODE_FLAG_INTERLACE)
1254                                 continue;
1255                 }
1256                 return mode;
1257         }
1258
1259         if (prefer_non_interlace) {
1260                 prefer_non_interlace = false;
1261                 goto again;
1262         }
1263
1264 create_mode:
1265         mode = drm_mode_create_from_cmdline_mode(fb_helper_conn->connector->dev,
1266                                                  cmdline_mode);
1267         list_add(&mode->head, &fb_helper_conn->connector->modes);
1268         return mode;
1269 }
1270 EXPORT_SYMBOL(drm_pick_cmdline_mode);
1271
1272 static bool drm_connector_enabled(struct drm_connector *connector, bool strict)
1273 {
1274         bool enable;
1275
1276         if (strict)
1277                 enable = connector->status == connector_status_connected;
1278         else
1279                 enable = connector->status != connector_status_disconnected;
1280
1281         return enable;
1282 }
1283
1284 static void drm_enable_connectors(struct drm_fb_helper *fb_helper,
1285                                   bool *enabled)
1286 {
1287         bool any_enabled = false;
1288         struct drm_connector *connector;
1289         int i = 0;
1290
1291         for (i = 0; i < fb_helper->connector_count; i++) {
1292                 connector = fb_helper->connector_info[i]->connector;
1293                 enabled[i] = drm_connector_enabled(connector, true);
1294                 DRM_DEBUG_KMS("connector %d enabled? %s\n", connector->base.id,
1295                           enabled[i] ? "yes" : "no");
1296                 any_enabled |= enabled[i];
1297         }
1298
1299         if (any_enabled)
1300                 return;
1301
1302         for (i = 0; i < fb_helper->connector_count; i++) {
1303                 connector = fb_helper->connector_info[i]->connector;
1304                 enabled[i] = drm_connector_enabled(connector, false);
1305         }
1306 }
1307
1308 static bool drm_target_cloned(struct drm_fb_helper *fb_helper,
1309                               struct drm_display_mode **modes,
1310                               bool *enabled, int width, int height)
1311 {
1312         int count, i, j;
1313         bool can_clone = false;
1314         struct drm_fb_helper_connector *fb_helper_conn;
1315         struct drm_display_mode *dmt_mode, *mode;
1316
1317         /* only contemplate cloning in the single crtc case */
1318         if (fb_helper->crtc_count > 1)
1319                 return false;
1320
1321         count = 0;
1322         for (i = 0; i < fb_helper->connector_count; i++) {
1323                 if (enabled[i])
1324                         count++;
1325         }
1326
1327         /* only contemplate cloning if more than one connector is enabled */
1328         if (count <= 1)
1329                 return false;
1330
1331         /* check the command line or if nothing common pick 1024x768 */
1332         can_clone = true;
1333         for (i = 0; i < fb_helper->connector_count; i++) {
1334                 if (!enabled[i])
1335                         continue;
1336                 fb_helper_conn = fb_helper->connector_info[i];
1337                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1338                 if (!modes[i]) {
1339                         can_clone = false;
1340                         break;
1341                 }
1342                 for (j = 0; j < i; j++) {
1343                         if (!enabled[j])
1344                                 continue;
1345                         if (!drm_mode_equal(modes[j], modes[i]))
1346                                 can_clone = false;
1347                 }
1348         }
1349
1350         if (can_clone) {
1351                 DRM_DEBUG_KMS("can clone using command line\n");
1352                 return true;
1353         }
1354
1355         /* try and find a 1024x768 mode on each connector */
1356         can_clone = true;
1357         dmt_mode = drm_mode_find_dmt(fb_helper->dev, 1024, 768, 60, false);
1358
1359         for (i = 0; i < fb_helper->connector_count; i++) {
1360
1361                 if (!enabled[i])
1362                         continue;
1363
1364                 fb_helper_conn = fb_helper->connector_info[i];
1365                 list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1366                         if (drm_mode_equal(mode, dmt_mode))
1367                                 modes[i] = mode;
1368                 }
1369                 if (!modes[i])
1370                         can_clone = false;
1371         }
1372
1373         if (can_clone) {
1374                 DRM_DEBUG_KMS("can clone using 1024x768\n");
1375                 return true;
1376         }
1377         DRM_INFO("kms: can't enable cloning when we probably wanted to.\n");
1378         return false;
1379 }
1380
1381 static bool drm_target_preferred(struct drm_fb_helper *fb_helper,
1382                                  struct drm_display_mode **modes,
1383                                  bool *enabled, int width, int height)
1384 {
1385         struct drm_fb_helper_connector *fb_helper_conn;
1386         int i;
1387
1388         for (i = 0; i < fb_helper->connector_count; i++) {
1389                 fb_helper_conn = fb_helper->connector_info[i];
1390
1391                 if (enabled[i] == false)
1392                         continue;
1393
1394                 DRM_DEBUG_KMS("looking for cmdline mode on connector %d\n",
1395                               fb_helper_conn->connector->base.id);
1396
1397                 /* got for command line mode first */
1398                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1399                 if (!modes[i]) {
1400                         DRM_DEBUG_KMS("looking for preferred mode on connector %d\n",
1401                                       fb_helper_conn->connector->base.id);
1402                         modes[i] = drm_has_preferred_mode(fb_helper_conn, width, height);
1403                 }
1404                 /* No preferred modes, pick one off the list */
1405                 if (!modes[i] && !list_empty(&fb_helper_conn->connector->modes)) {
1406                         list_for_each_entry(modes[i], &fb_helper_conn->connector->modes, head)
1407                                 break;
1408                 }
1409                 DRM_DEBUG_KMS("found mode %s\n", modes[i] ? modes[i]->name :
1410                           "none");
1411         }
1412         return true;
1413 }
1414
1415 static int drm_pick_crtcs(struct drm_fb_helper *fb_helper,
1416                           struct drm_fb_helper_crtc **best_crtcs,
1417                           struct drm_display_mode **modes,
1418                           int n, int width, int height)
1419 {
1420         int c, o;
1421         struct drm_device *dev = fb_helper->dev;
1422         struct drm_connector *connector;
1423         struct drm_connector_helper_funcs *connector_funcs;
1424         struct drm_encoder *encoder;
1425         int my_score, best_score, score;
1426         struct drm_fb_helper_crtc **crtcs, *crtc;
1427         struct drm_fb_helper_connector *fb_helper_conn;
1428
1429         if (n == fb_helper->connector_count)
1430                 return 0;
1431
1432         fb_helper_conn = fb_helper->connector_info[n];
1433         connector = fb_helper_conn->connector;
1434
1435         best_crtcs[n] = NULL;
1436         best_score = drm_pick_crtcs(fb_helper, best_crtcs, modes, n+1, width, height);
1437         if (modes[n] == NULL)
1438                 return best_score;
1439
1440         crtcs = kzalloc(dev->mode_config.num_connector *
1441                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1442         if (!crtcs)
1443                 return best_score;
1444
1445         my_score = 1;
1446         if (connector->status == connector_status_connected)
1447                 my_score++;
1448         if (drm_has_cmdline_mode(fb_helper_conn))
1449                 my_score++;
1450         if (drm_has_preferred_mode(fb_helper_conn, width, height))
1451                 my_score++;
1452
1453         connector_funcs = connector->helper_private;
1454         encoder = connector_funcs->best_encoder(connector);
1455         if (!encoder)
1456                 goto out;
1457
1458         /* select a crtc for this connector and then attempt to configure
1459            remaining connectors */
1460         for (c = 0; c < fb_helper->crtc_count; c++) {
1461                 crtc = &fb_helper->crtc_info[c];
1462
1463                 if ((encoder->possible_crtcs & (1 << c)) == 0)
1464                         continue;
1465
1466                 for (o = 0; o < n; o++)
1467                         if (best_crtcs[o] == crtc)
1468                                 break;
1469
1470                 if (o < n) {
1471                         /* ignore cloning unless only a single crtc */
1472                         if (fb_helper->crtc_count > 1)
1473                                 continue;
1474
1475                         if (!drm_mode_equal(modes[o], modes[n]))
1476                                 continue;
1477                 }
1478
1479                 crtcs[n] = crtc;
1480                 memcpy(crtcs, best_crtcs, n * sizeof(struct drm_fb_helper_crtc *));
1481                 score = my_score + drm_pick_crtcs(fb_helper, crtcs, modes, n + 1,
1482                                                   width, height);
1483                 if (score > best_score) {
1484                         best_score = score;
1485                         memcpy(best_crtcs, crtcs,
1486                                dev->mode_config.num_connector *
1487                                sizeof(struct drm_fb_helper_crtc *));
1488                 }
1489         }
1490 out:
1491         kfree(crtcs);
1492         return best_score;
1493 }
1494
1495 static void drm_setup_crtcs(struct drm_fb_helper *fb_helper)
1496 {
1497         struct drm_device *dev = fb_helper->dev;
1498         struct drm_fb_helper_crtc **crtcs;
1499         struct drm_display_mode **modes;
1500         struct drm_mode_set *modeset;
1501         bool *enabled;
1502         int width, height;
1503         int i;
1504
1505         DRM_DEBUG_KMS("\n");
1506
1507         width = dev->mode_config.max_width;
1508         height = dev->mode_config.max_height;
1509
1510         crtcs = kcalloc(dev->mode_config.num_connector,
1511                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1512         modes = kcalloc(dev->mode_config.num_connector,
1513                         sizeof(struct drm_display_mode *), GFP_KERNEL);
1514         enabled = kcalloc(dev->mode_config.num_connector,
1515                           sizeof(bool), GFP_KERNEL);
1516         if (!crtcs || !modes || !enabled) {
1517                 DRM_ERROR("Memory allocation failed\n");
1518                 goto out;
1519         }
1520
1521
1522         drm_enable_connectors(fb_helper, enabled);
1523
1524         if (!(fb_helper->funcs->initial_config &&
1525               fb_helper->funcs->initial_config(fb_helper, crtcs, modes,
1526                                                enabled, width, height))) {
1527                 memset(modes, 0, dev->mode_config.num_connector*sizeof(modes[0]));
1528                 memset(crtcs, 0, dev->mode_config.num_connector*sizeof(crtcs[0]));
1529
1530                 if (!drm_target_cloned(fb_helper,
1531                                        modes, enabled, width, height) &&
1532                     !drm_target_preferred(fb_helper,
1533                                           modes, enabled, width, height))
1534                         DRM_ERROR("Unable to find initial modes\n");
1535
1536                 DRM_DEBUG_KMS("picking CRTCs for %dx%d config\n",
1537                               width, height);
1538
1539                 drm_pick_crtcs(fb_helper, crtcs, modes, 0, width, height);
1540         }
1541
1542         /* need to set the modesets up here for use later */
1543         /* fill out the connector<->crtc mappings into the modesets */
1544         for (i = 0; i < fb_helper->crtc_count; i++) {
1545                 modeset = &fb_helper->crtc_info[i].mode_set;
1546                 modeset->num_connectors = 0;
1547                 modeset->fb = NULL;
1548         }
1549
1550         for (i = 0; i < fb_helper->connector_count; i++) {
1551                 struct drm_display_mode *mode = modes[i];
1552                 struct drm_fb_helper_crtc *fb_crtc = crtcs[i];
1553                 modeset = &fb_crtc->mode_set;
1554
1555                 if (mode && fb_crtc) {
1556                         DRM_DEBUG_KMS("desired mode %s set on crtc %d\n",
1557                                       mode->name, fb_crtc->mode_set.crtc->base.id);
1558                         fb_crtc->desired_mode = mode;
1559                         if (modeset->mode)
1560                                 drm_mode_destroy(dev, modeset->mode);
1561                         modeset->mode = drm_mode_duplicate(dev,
1562                                                            fb_crtc->desired_mode);
1563                         modeset->connectors[modeset->num_connectors++] = fb_helper->connector_info[i]->connector;
1564                         modeset->fb = fb_helper->fb;
1565                 }
1566         }
1567
1568         /* Clear out any old modes if there are no more connected outputs. */
1569         for (i = 0; i < fb_helper->crtc_count; i++) {
1570                 modeset = &fb_helper->crtc_info[i].mode_set;
1571                 if (modeset->num_connectors == 0) {
1572                         BUG_ON(modeset->fb);
1573                         BUG_ON(modeset->num_connectors);
1574                         if (modeset->mode)
1575                                 drm_mode_destroy(dev, modeset->mode);
1576                         modeset->mode = NULL;
1577                 }
1578         }
1579 out:
1580         kfree(crtcs);
1581         kfree(modes);
1582         kfree(enabled);
1583 }
1584
1585 /**
1586  * drm_fb_helper_initial_config - setup a sane initial connector configuration
1587  * @fb_helper: fb_helper device struct
1588  * @bpp_sel: bpp value to use for the framebuffer configuration
1589  *
1590  * Scans the CRTCs and connectors and tries to put together an initial setup.
1591  * At the moment, this is a cloned configuration across all heads with
1592  * a new framebuffer object as the backing store.
1593  *
1594  * Note that this also registers the fbdev and so allows userspace to call into
1595  * the driver through the fbdev interfaces.
1596  *
1597  * This function will call down into the ->fb_probe callback to let
1598  * the driver allocate and initialize the fbdev info structure and the drm
1599  * framebuffer used to back the fbdev. drm_fb_helper_fill_var() and
1600  * drm_fb_helper_fill_fix() are provided as helpers to setup simple default
1601  * values for the fbdev info structure.
1602  *
1603  * RETURNS:
1604  * Zero if everything went ok, nonzero otherwise.
1605  */
1606 bool drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel)
1607 {
1608         struct drm_device *dev = fb_helper->dev;
1609         int count = 0;
1610
1611         mutex_lock(&dev->mode_config.mutex);
1612         count = drm_fb_helper_probe_connector_modes(fb_helper,
1613                                                     dev->mode_config.max_width,
1614                                                     dev->mode_config.max_height);
1615         mutex_unlock(&dev->mode_config.mutex);
1616         /*
1617          * we shouldn't end up with no modes here.
1618          */
1619         if (count == 0)
1620                 dev_info(fb_helper->dev->dev, "No connectors reported connected with modes\n");
1621
1622         drm_setup_crtcs(fb_helper);
1623
1624         return drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
1625 }
1626 EXPORT_SYMBOL(drm_fb_helper_initial_config);
1627
1628 /**
1629  * drm_fb_helper_hotplug_event - respond to a hotplug notification by
1630  *                               probing all the outputs attached to the fb
1631  * @fb_helper: the drm_fb_helper
1632  *
1633  * Scan the connectors attached to the fb_helper and try to put together a
1634  * setup after *notification of a change in output configuration.
1635  *
1636  * Called at runtime, takes the mode config locks to be able to check/change the
1637  * modeset configuration. Must be run from process context (which usually means
1638  * either the output polling work or a work item launched from the driver's
1639  * hotplug interrupt).
1640  *
1641  * Note that drivers may call this even before calling
1642  * drm_fb_helper_initial_config but only aftert drm_fb_helper_init. This allows
1643  * for a race-free fbcon setup and will make sure that the fbdev emulation will
1644  * not miss any hotplug events.
1645  *
1646  * RETURNS:
1647  * 0 on success and a non-zero error code otherwise.
1648  */
1649 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
1650 {
1651         struct drm_device *dev = fb_helper->dev;
1652         u32 max_width, max_height;
1653
1654         mutex_lock(&fb_helper->dev->mode_config.mutex);
1655         if (!fb_helper->fb || !drm_fb_helper_is_bound(fb_helper)) {
1656                 fb_helper->delayed_hotplug = true;
1657                 mutex_unlock(&fb_helper->dev->mode_config.mutex);
1658                 return 0;
1659         }
1660         DRM_DEBUG_KMS("\n");
1661
1662         max_width = fb_helper->fb->width;
1663         max_height = fb_helper->fb->height;
1664
1665         drm_fb_helper_probe_connector_modes(fb_helper, max_width, max_height);
1666         mutex_unlock(&fb_helper->dev->mode_config.mutex);
1667
1668         drm_modeset_lock_all(dev);
1669         drm_setup_crtcs(fb_helper);
1670         drm_modeset_unlock_all(dev);
1671         drm_fb_helper_set_par(fb_helper->fbdev);
1672
1673         return 0;
1674 }
1675 EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
1676
1677 /* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
1678  * but the module doesn't depend on any fb console symbols.  At least
1679  * attempt to load fbcon to avoid leaving the system without a usable console.
1680  */
1681 #if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT)
1682 static int __init drm_fb_helper_modinit(void)
1683 {
1684         const char *name = "fbcon";
1685         struct module *fbcon;
1686
1687         mutex_lock(&module_mutex);
1688         fbcon = find_module(name);
1689         mutex_unlock(&module_mutex);
1690
1691         if (!fbcon)
1692                 request_module_nowait(name);
1693         return 0;
1694 }
1695
1696 module_init(drm_fb_helper_modinit);
1697 #endif