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         bool do_delayed = false;
 351
 352         drm_modeset_lock_all(dev);
 353         ret = restore_fbdev_mode(fb_helper);
 354
 355         do_delayed = fb_helper->delayed_hotplug;
 356         if (do_delayed)
 357                 fb_helper->delayed_hotplug = false;
 358         drm_modeset_unlock_all(dev);
 359
 360         if (do_delayed)
 361                 drm_fb_helper_hotplug_event(fb_helper);
 362         return ret;
 363 }
 364 EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked);
 365
 366 /*
 367  * restore fbcon display for all kms driver's using this helper, used for sysrq
 368  * and panic handling.
 369  */
 370 static bool drm_fb_helper_force_kernel_mode(void)
 371 {
 372         bool ret, error = false;
 373         struct drm_fb_helper *helper;
 374
 375         if (list_empty(&kernel_fb_helper_list))
 376                 return false;
 377
 378         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 379                 struct drm_device *dev = helper->dev;
 380
 381                 if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
 382                         continue;
 383
 384                 /*
 385                  * NOTE: Use trylock mode to avoid deadlocks and sleeping in
 386                  * panic context.
 387                  */
 388                 if (__drm_modeset_lock_all(dev, true) != 0) {
 389                         error = true;
 390                         continue;
 391                 }
 392
 393                 ret = drm_fb_helper_restore_fbdev_mode(helper);
 394                 if (ret)
 395                         error = true;
 396
 397                 drm_modeset_unlock_all(dev);
 398         }
 399         return error;
 400 }
 401
 402 static int drm_fb_helper_panic(struct notifier_block *n, unsigned long ununsed,
 403                         void *panic_str)
 404 {
 405         /*
 406          * It's a waste of time and effort to switch back to text console
 407          * if the kernel should reboot before panic messages can be seen.
 408          */
 409         if (panic_timeout < 0)
 410                 return 0;
 411
 412         pr_err("panic occurred, switching back to text console\n");
 413         return drm_fb_helper_force_kernel_mode();
 414 }
 415
 416 static struct notifier_block paniced = {
 417         .notifier_call = drm_fb_helper_panic,
 418 };
 419
 420 static bool drm_fb_helper_is_bound(struct drm_fb_helper *fb_helper)
 421 {
 422         struct drm_device *dev = fb_helper->dev;
 423         struct drm_crtc *crtc;
 424         int bound = 0, crtcs_bound = 0;
 425
 426         /* Sometimes user space wants everything disabled, so don't steal the
 427          * display if there's a master. */
 428         if (dev->primary->master)
 429                 return false;
 430
 431         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 432                 if (crtc->primary->fb)
 433                         crtcs_bound++;
 434                 if (crtc->primary->fb == fb_helper->fb)
 435                         bound++;
 436         }
 437
 438         if (bound < crtcs_bound)
 439                 return false;
 440
 441         return true;
 442 }
 443
 444 #ifdef CONFIG_MAGIC_SYSRQ
 445 static void drm_fb_helper_restore_work_fn(struct work_struct *ignored)
 446 {
 447         bool ret;
 448         ret = drm_fb_helper_force_kernel_mode();
 449         if (ret == true)
 450                 DRM_ERROR("Failed to restore crtc configuration\n");
 451 }
 452 static DECLARE_WORK(drm_fb_helper_restore_work, drm_fb_helper_restore_work_fn);
 453
 454 static void drm_fb_helper_sysrq(int dummy1)
 455 {
 456         schedule_work(&drm_fb_helper_restore_work);
 457 }
 458
 459 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = {
 460         .handler = drm_fb_helper_sysrq,
 461         .help_msg = "force-fb(V)",
 462         .action_msg = "Restore framebuffer console",
 463 };
 464 #else
 465 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { };
 466 #endif
 467
 468 static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
 469 {
 470         struct drm_fb_helper *fb_helper = info->par;
 471         struct drm_device *dev = fb_helper->dev;
 472         struct drm_crtc *crtc;
 473         struct drm_connector *connector;
 474         int i, j;
 475
 476         /*
 477          * fbdev->blank can be called from irq context in case of a panic.
 478          * Since we already have our own special panic handler which will
 479          * restore the fbdev console mode completely, just bail out early.
 480          */
 481         if (oops_in_progress)
 482                 return;
 483
 484         /*
 485          * For each CRTC in this fb, turn the connectors on/off.
 486          */
 487         drm_modeset_lock_all(dev);
 488         if (!drm_fb_helper_is_bound(fb_helper)) {
 489                 drm_modeset_unlock_all(dev);
 490                 return;
 491         }
 492
 493         for (i = 0; i < fb_helper->crtc_count; i++) {
 494                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
 495
 496                 if (!crtc->enabled)
 497                         continue;
 498
 499                 /* Walk the connectors & encoders on this fb turning them on/off */
 500                 for (j = 0; j < fb_helper->connector_count; j++) {
 501                         connector = fb_helper->connector_info[j]->connector;
 502                         connector->funcs->dpms(connector, dpms_mode);
 503                         drm_object_property_set_value(&connector->base,
 504                                 dev->mode_config.dpms_property, dpms_mode);
 505                 }
 506         }
 507         drm_modeset_unlock_all(dev);
 508 }
 509
 510 /**
 511  * drm_fb_helper_blank - implementation for ->fb_blank
 512  * @blank: desired blanking state
 513  * @info: fbdev registered by the helper
 514  */
 515 int drm_fb_helper_blank(int blank, struct fb_info *info)
 516 {
 517         switch (blank) {
 518         /* Display: On; HSync: On, VSync: On */
 519         case FB_BLANK_UNBLANK:
 520                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON);
 521                 break;
 522         /* Display: Off; HSync: On, VSync: On */
 523         case FB_BLANK_NORMAL:
 524                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 525                 break;
 526         /* Display: Off; HSync: Off, VSync: On */
 527         case FB_BLANK_HSYNC_SUSPEND:
 528                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 529                 break;
 530         /* Display: Off; HSync: On, VSync: Off */
 531         case FB_BLANK_VSYNC_SUSPEND:
 532                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND);
 533                 break;
 534         /* Display: Off; HSync: Off, VSync: Off */
 535         case FB_BLANK_POWERDOWN:
 536                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF);
 537                 break;
 538         }
 539         return 0;
 540 }
 541 EXPORT_SYMBOL(drm_fb_helper_blank);
 542
 543 static void drm_fb_helper_crtc_free(struct drm_fb_helper *helper)
 544 {
 545         int i;
 546
 547         for (i = 0; i < helper->connector_count; i++)
 548                 kfree(helper->connector_info[i]);
 549         kfree(helper->connector_info);
 550         for (i = 0; i < helper->crtc_count; i++) {
 551                 kfree(helper->crtc_info[i].mode_set.connectors);
 552                 if (helper->crtc_info[i].mode_set.mode)
 553                         drm_mode_destroy(helper->dev, helper->crtc_info[i].mode_set.mode);
 554         }
 555         kfree(helper->crtc_info);
 556 }
 557
 558 /**
 559  * drm_fb_helper_prepare - setup a drm_fb_helper structure
 560  * @dev: DRM device
 561  * @helper: driver-allocated fbdev helper structure to set up
 562  * @funcs: pointer to structure of functions associate with this helper
 563  *
 564  * Sets up the bare minimum to make the framebuffer helper usable. This is
 565  * useful to implement race-free initialization of the polling helpers.
 566  */
 567 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
 568                            const struct drm_fb_helper_funcs *funcs)
 569 {
 570         INIT_LIST_HEAD(&helper->kernel_fb_list);
 571         helper->funcs = funcs;
 572         helper->dev = dev;
 573 }
 574 EXPORT_SYMBOL(drm_fb_helper_prepare);
 575
 576 /**
 577  * drm_fb_helper_init - initialize a drm_fb_helper structure
 578  * @dev: drm device
 579  * @fb_helper: driver-allocated fbdev helper structure to initialize
 580  * @crtc_count: maximum number of crtcs to support in this fbdev emulation
 581  * @max_conn_count: max connector count
 582  *
 583  * This allocates the structures for the fbdev helper with the given limits.
 584  * Note that this won't yet touch the hardware (through the driver interfaces)
 585  * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
 586  * to allow driver writes more control over the exact init sequence.
 587  *
 588  * Drivers must call drm_fb_helper_prepare() before calling this function.
 589  *
 590  * RETURNS:
 591  * Zero if everything went ok, nonzero otherwise.
 592  */
 593 int drm_fb_helper_init(struct drm_device *dev,
 594                        struct drm_fb_helper *fb_helper,
 595                        int crtc_count, int max_conn_count)
 596 {
 597         struct drm_crtc *crtc;
 598         int i;
 599
 600         if (!max_conn_count)
 601                 return -EINVAL;
 602
 603         fb_helper->crtc_info = kcalloc(crtc_count, sizeof(struct drm_fb_helper_crtc), GFP_KERNEL);
 604         if (!fb_helper->crtc_info)
 605                 return -ENOMEM;
 606
 607         fb_helper->crtc_count = crtc_count;
 608         fb_helper->connector_info = kcalloc(dev->mode_config.num_connector, sizeof(struct drm_fb_helper_connector *), GFP_KERNEL);
 609         if (!fb_helper->connector_info) {
 610                 kfree(fb_helper->crtc_info);
 611                 return -ENOMEM;
 612         }
 613         fb_helper->connector_info_alloc_count = dev->mode_config.num_connector;
 614         fb_helper->connector_count = 0;
 615
 616         for (i = 0; i < crtc_count; i++) {
 617                 fb_helper->crtc_info[i].mode_set.connectors =
 618                         kcalloc(max_conn_count,
 619                                 sizeof(struct drm_connector *),
 620                                 GFP_KERNEL);
 621
 622                 if (!fb_helper->crtc_info[i].mode_set.connectors)
 623                         goto out_free;
 624                 fb_helper->crtc_info[i].mode_set.num_connectors = 0;
 625         }
 626
 627         i = 0;
 628         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 629                 fb_helper->crtc_info[i].mode_set.crtc = crtc;
 630                 i++;
 631         }
 632
 633         return 0;
 634 out_free:
 635         drm_fb_helper_crtc_free(fb_helper);
 636         return -ENOMEM;
 637 }
 638 EXPORT_SYMBOL(drm_fb_helper_init);
 639
 640 void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
 641 {
 642         if (!list_empty(&fb_helper->kernel_fb_list)) {
 643                 list_del(&fb_helper->kernel_fb_list);
 644                 if (list_empty(&kernel_fb_helper_list)) {
 645                         pr_info("drm: unregistered panic notifier\n");
 646                         atomic_notifier_chain_unregister(&panic_notifier_list,
 647                                                          &paniced);
 648                         unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
 649                 }
 650         }
 651
 652         drm_fb_helper_crtc_free(fb_helper);
 653
 654 }
 655 EXPORT_SYMBOL(drm_fb_helper_fini);
 656
 657 static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
 658                      u16 blue, u16 regno, struct fb_info *info)
 659 {
 660         struct drm_fb_helper *fb_helper = info->par;
 661         struct drm_framebuffer *fb = fb_helper->fb;
 662         int pindex;
 663
 664         if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
 665                 u32 *palette;
 666                 u32 value;
 667                 /* place color in psuedopalette */
 668                 if (regno > 16)
 669                         return -EINVAL;
 670                 palette = (u32 *)info->pseudo_palette;
 671                 red >>= (16 - info->var.red.length);
 672                 green >>= (16 - info->var.green.length);
 673                 blue >>= (16 - info->var.blue.length);
 674                 value = (red << info->var.red.offset) |
 675                         (green << info->var.green.offset) |
 676                         (blue << info->var.blue.offset);
 677                 if (info->var.transp.length > 0) {
 678                         u32 mask = (1 << info->var.transp.length) - 1;
 679                         mask <<= info->var.transp.offset;
 680                         value |= mask;
 681                 }
 682                 palette[regno] = value;
 683                 return 0;
 684         }
 685
 686         /*
 687          * The driver really shouldn't advertise pseudo/directcolor
 688          * visuals if it can't deal with the palette.
 689          */
 690         if (WARN_ON(!fb_helper->funcs->gamma_set ||
 691                     !fb_helper->funcs->gamma_get))
 692                 return -EINVAL;
 693
 694         pindex = regno;
 695
 696         if (fb->bits_per_pixel == 16) {
 697                 pindex = regno << 3;
 698
 699                 if (fb->depth == 16 && regno > 63)
 700                         return -EINVAL;
 701                 if (fb->depth == 15 && regno > 31)
 702                         return -EINVAL;
 703
 704                 if (fb->depth == 16) {
 705                         u16 r, g, b;
 706                         int i;
 707                         if (regno < 32) {
 708                                 for (i = 0; i < 8; i++)
 709                                         fb_helper->funcs->gamma_set(crtc, red,
 710                                                 green, blue, pindex + i);
 711                         }
 712
 713                         fb_helper->funcs->gamma_get(crtc, &r,
 714                                                     &g, &b,
 715                                                     pindex >> 1);
 716
 717                         for (i = 0; i < 4; i++)
 718                                 fb_helper->funcs->gamma_set(crtc, r,
 719                                                             green, b,
 720                                                             (pindex >> 1) + i);
 721                 }
 722         }
 723
 724         if (fb->depth != 16)
 725                 fb_helper->funcs->gamma_set(crtc, red, green, blue, pindex);
 726         return 0;
 727 }
 728
 729 /**
 730  * drm_fb_helper_setcmap - implementation for ->fb_setcmap
 731  * @cmap: cmap to set
 732  * @info: fbdev registered by the helper
 733  */
 734 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
 735 {
 736         struct drm_fb_helper *fb_helper = info->par;
 737         struct drm_device *dev = fb_helper->dev;
 738         struct drm_crtc_helper_funcs *crtc_funcs;
 739         u16 *red, *green, *blue, *transp;
 740         struct drm_crtc *crtc;
 741         int i, j, rc = 0;
 742         int start;
 743
 744         drm_modeset_lock_all(dev);
 745         if (!drm_fb_helper_is_bound(fb_helper)) {
 746                 drm_modeset_unlock_all(dev);
 747                 return -EBUSY;
 748         }
 749
 750         for (i = 0; i < fb_helper->crtc_count; i++) {
 751                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
 752                 crtc_funcs = crtc->helper_private;
 753
 754                 red = cmap->red;
 755                 green = cmap->green;
 756                 blue = cmap->blue;
 757                 transp = cmap->transp;
 758                 start = cmap->start;
 759
 760                 for (j = 0; j < cmap->len; j++) {
 761                         u16 hred, hgreen, hblue, htransp = 0xffff;
 762
 763                         hred = *red++;
 764                         hgreen = *green++;
 765                         hblue = *blue++;
 766
 767                         if (transp)
 768                                 htransp = *transp++;
 769
 770                         rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
 771                         if (rc)
 772                                 goto out;
 773                 }
 774                 if (crtc_funcs->load_lut)
 775                         crtc_funcs->load_lut(crtc);
 776         }
 777  out:
 778         drm_modeset_unlock_all(dev);
 779         return rc;
 780 }
 781 EXPORT_SYMBOL(drm_fb_helper_setcmap);
 782
 783 /**
 784  * drm_fb_helper_check_var - implementation for ->fb_check_var
 785  * @var: screeninfo to check
 786  * @info: fbdev registered by the helper
 787  */
 788 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 789                             struct fb_info *info)
 790 {
 791         struct drm_fb_helper *fb_helper = info->par;
 792         struct drm_framebuffer *fb = fb_helper->fb;
 793         int depth;
 794
 795         if (var->pixclock != 0 || in_dbg_master())
 796                 return -EINVAL;
 797
 798         /* Need to resize the fb object !!! */
 799         if (var->bits_per_pixel > fb->bits_per_pixel ||
 800             var->xres > fb->width || var->yres > fb->height ||
 801             var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
 802                 DRM_DEBUG("fb userspace requested width/height/bpp is greater than current fb "
 803                           "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
 804                           var->xres, var->yres, var->bits_per_pixel,
 805                           var->xres_virtual, var->yres_virtual,
 806                           fb->width, fb->height, fb->bits_per_pixel);
 807                 return -EINVAL;
 808         }
 809
 810         switch (var->bits_per_pixel) {
 811         case 16:
 812                 depth = (var->green.length == 6) ? 16 : 15;
 813                 break;
 814         case 32:
 815                 depth = (var->transp.length > 0) ? 32 : 24;
 816                 break;
 817         default:
 818                 depth = var->bits_per_pixel;
 819                 break;
 820         }
 821
 822         switch (depth) {
 823         case 8:
 824                 var->red.offset = 0;
 825                 var->green.offset = 0;
 826                 var->blue.offset = 0;
 827                 var->red.length = 8;
 828                 var->green.length = 8;
 829                 var->blue.length = 8;
 830                 var->transp.length = 0;
 831                 var->transp.offset = 0;
 832                 break;
 833         case 15:
 834                 var->red.offset = 10;
 835                 var->green.offset = 5;
 836                 var->blue.offset = 0;
 837                 var->red.length = 5;
 838                 var->green.length = 5;
 839                 var->blue.length = 5;
 840                 var->transp.length = 1;
 841                 var->transp.offset = 15;
 842                 break;
 843         case 16:
 844                 var->red.offset = 11;
 845                 var->green.offset = 5;
 846                 var->blue.offset = 0;
 847                 var->red.length = 5;
 848                 var->green.length = 6;
 849                 var->blue.length = 5;
 850                 var->transp.length = 0;
 851                 var->transp.offset = 0;
 852                 break;
 853         case 24:
 854                 var->red.offset = 16;
 855                 var->green.offset = 8;
 856                 var->blue.offset = 0;
 857                 var->red.length = 8;
 858                 var->green.length = 8;
 859                 var->blue.length = 8;
 860                 var->transp.length = 0;
 861                 var->transp.offset = 0;
 862                 break;
 863         case 32:
 864                 var->red.offset = 16;
 865                 var->green.offset = 8;
 866                 var->blue.offset = 0;
 867                 var->red.length = 8;
 868                 var->green.length = 8;
 869                 var->blue.length = 8;
 870                 var->transp.length = 8;
 871                 var->transp.offset = 24;
 872                 break;
 873         default:
 874                 return -EINVAL;
 875         }
 876         return 0;
 877 }
 878 EXPORT_SYMBOL(drm_fb_helper_check_var);
 879
 880 /**
 881  * drm_fb_helper_set_par - implementation for ->fb_set_par
 882  * @info: fbdev registered by the helper
 883  *
 884  * This will let fbcon do the mode init and is called at initialization time by
 885  * the fbdev core when registering the driver, and later on through the hotplug
 886  * callback.
 887  */
 888 int drm_fb_helper_set_par(struct fb_info *info)
 889 {
 890         struct drm_fb_helper *fb_helper = info->par;
 891         struct fb_var_screeninfo *var = &info->var;
 892
 893         if (var->pixclock != 0) {
 894                 DRM_ERROR("PIXEL CLOCK SET\n");
 895                 return -EINVAL;
 896         }
 897
 898         drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper);
 899
 900         return 0;
 901 }
 902 EXPORT_SYMBOL(drm_fb_helper_set_par);
 903
 904 /**
 905  * drm_fb_helper_pan_display - implementation for ->fb_pan_display
 906  * @var: updated screen information
 907  * @info: fbdev registered by the helper
 908  */
 909 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
 910                               struct fb_info *info)
 911 {
 912         struct drm_fb_helper *fb_helper = info->par;
 913         struct drm_device *dev = fb_helper->dev;
 914         struct drm_mode_set *modeset;
 915         int ret = 0;
 916         int i;
 917
 918         drm_modeset_lock_all(dev);
 919         if (!drm_fb_helper_is_bound(fb_helper)) {
 920                 drm_modeset_unlock_all(dev);
 921                 return -EBUSY;
 922         }
 923
 924         for (i = 0; i < fb_helper->crtc_count; i++) {
 925                 modeset = &fb_helper->crtc_info[i].mode_set;
 926
 927                 modeset->x = var->xoffset;
 928                 modeset->y = var->yoffset;
 929
 930                 if (modeset->num_connectors) {
 931                         ret = drm_mode_set_config_internal(modeset);
 932                         if (!ret) {
 933                                 info->var.xoffset = var->xoffset;
 934                                 info->var.yoffset = var->yoffset;
 935                         }
 936                 }
 937         }
 938         drm_modeset_unlock_all(dev);
 939         return ret;
 940 }
 941 EXPORT_SYMBOL(drm_fb_helper_pan_display);
 942
 943 /*
 944  * Allocates the backing storage and sets up the fbdev info structure through
 945  * the ->fb_probe callback and then registers the fbdev and sets up the panic
 946  * notifier.
 947  */
 948 static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
 949                                          int preferred_bpp)
 950 {
 951         int ret = 0;
 952         int crtc_count = 0;
 953         int i;
 954         struct fb_info *info;
 955         struct drm_fb_helper_surface_size sizes;
 956         int gamma_size = 0;
 957
 958         memset(&sizes, 0, sizeof(struct drm_fb_helper_surface_size));
 959         sizes.surface_depth = 24;
 960         sizes.surface_bpp = 32;
 961         sizes.fb_width = (unsigned)-1;
 962         sizes.fb_height = (unsigned)-1;
 963
 964         /* if driver picks 8 or 16 by default use that
 965            for both depth/bpp */
 966         if (preferred_bpp != sizes.surface_bpp)
 967                 sizes.surface_depth = sizes.surface_bpp = preferred_bpp;
 968
 969         /* first up get a count of crtcs now in use and new min/maxes width/heights */
 970         for (i = 0; i < fb_helper->connector_count; i++) {
 971                 struct drm_fb_helper_connector *fb_helper_conn = fb_helper->connector_info[i];
 972                 struct drm_cmdline_mode *cmdline_mode;
 973
 974                 cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
 975
 976                 if (cmdline_mode->bpp_specified) {
 977                         switch (cmdline_mode->bpp) {
 978                         case 8:
 979                                 sizes.surface_depth = sizes.surface_bpp = 8;
 980                                 break;
 981                         case 15:
 982                                 sizes.surface_depth = 15;
 983                                 sizes.surface_bpp = 16;
 984                                 break;
 985                         case 16:
 986                                 sizes.surface_depth = sizes.surface_bpp = 16;
 987                                 break;
 988                         case 24:
 989                                 sizes.surface_depth = sizes.surface_bpp = 24;
 990                                 break;
 991                         case 32:
 992                                 sizes.surface_depth = 24;
 993                                 sizes.surface_bpp = 32;
 994                                 break;
 995                         }
 996                         break;
 997                 }
 998         }
 999
1000         crtc_count = 0;
1001         for (i = 0; i < fb_helper->crtc_count; i++) {
1002                 struct drm_display_mode *desired_mode;
1003                 int x, y;
1004                 desired_mode = fb_helper->crtc_info[i].desired_mode;
1005                 x = fb_helper->crtc_info[i].x;
1006                 y = fb_helper->crtc_info[i].y;
1007                 if (desired_mode) {
1008                         if (gamma_size == 0)
1009                                 gamma_size = fb_helper->crtc_info[i].mode_set.crtc->gamma_size;
1010                         if (desired_mode->hdisplay + x < sizes.fb_width)
1011                                 sizes.fb_width = desired_mode->hdisplay + x;
1012                         if (desired_mode->vdisplay + y < sizes.fb_height)
1013                                 sizes.fb_height = desired_mode->vdisplay + y;
1014                         if (desired_mode->hdisplay + x > sizes.surface_width)
1015                                 sizes.surface_width = desired_mode->hdisplay + x;
1016                         if (desired_mode->vdisplay + y > sizes.surface_height)
1017                                 sizes.surface_height = desired_mode->vdisplay + y;
1018                         crtc_count++;
1019                 }
1020         }
1021
1022         if (crtc_count == 0 || sizes.fb_width == -1 || sizes.fb_height == -1) {
1023                 /* hmm everyone went away - assume VGA cable just fell out
1024                    and will come back later. */
1025                 DRM_INFO("Cannot find any crtc or sizes - going 1024x768\n");
1026                 sizes.fb_width = sizes.surface_width = 1024;
1027                 sizes.fb_height = sizes.surface_height = 768;
1028         }
1029
1030         /* push down into drivers */
1031         ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);
1032         if (ret < 0)
1033                 return ret;
1034
1035         info = fb_helper->fbdev;
1036
1037         /*
1038          * Set the fb pointer - usually drm_setup_crtcs does this for hotplug
1039          * events, but at init time drm_setup_crtcs needs to be called before
1040          * the fb is allocated (since we need to figure out the desired size of
1041          * the fb before we can allocate it ...). Hence we need to fix things up
1042          * here again.
1043          */
1044         for (i = 0; i < fb_helper->crtc_count; i++)
1045                 if (fb_helper->crtc_info[i].mode_set.num_connectors)
1046                         fb_helper->crtc_info[i].mode_set.fb = fb_helper->fb;
1047
1048
1049         info->var.pixclock = 0;
1050         if (register_framebuffer(info) < 0)
1051                 return -EINVAL;
1052
1053         dev_info(fb_helper->dev->dev, "fb%d: %s frame buffer device\n",
1054                         info->node, info->fix.id);
1055
1056         /* Switch back to kernel console on panic */
1057         /* multi card linked list maybe */
1058         if (list_empty(&kernel_fb_helper_list)) {
1059                 dev_info(fb_helper->dev->dev, "registered panic notifier\n");
1060                 atomic_notifier_chain_register(&panic_notifier_list,
1061                                                &paniced);
1062                 register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
1063         }
1064
1065         list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
1066
1067         return 0;
1068 }
1069
1070 /**
1071  * drm_fb_helper_fill_fix - initializes fixed fbdev information
1072  * @info: fbdev registered by the helper
1073  * @pitch: desired pitch
1074  * @depth: desired depth
1075  *
1076  * Helper to fill in the fixed fbdev information useful for a non-accelerated
1077  * fbdev emulations. Drivers which support acceleration methods which impose
1078  * additional constraints need to set up their own limits.
1079  *
1080  * Drivers should call this (or their equivalent setup code) from their
1081  * ->fb_probe callback.
1082  */
1083 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
1084                             uint32_t depth)
1085 {
1086         info->fix.type = FB_TYPE_PACKED_PIXELS;
1087         info->fix.visual = depth == 8 ? FB_VISUAL_PSEUDOCOLOR :
1088                 FB_VISUAL_TRUECOLOR;
1089         info->fix.mmio_start = 0;
1090         info->fix.mmio_len = 0;
1091         info->fix.type_aux = 0;
1092         info->fix.xpanstep = 1; /* doing it in hw */
1093         info->fix.ypanstep = 1; /* doing it in hw */
1094         info->fix.ywrapstep = 0;
1095         info->fix.accel = FB_ACCEL_NONE;
1096
1097         info->fix.line_length = pitch;
1098         return;
1099 }
1100 EXPORT_SYMBOL(drm_fb_helper_fill_fix);
1101
1102 /**
1103  * drm_fb_helper_fill_var - initalizes variable fbdev information
1104  * @info: fbdev instance to set up
1105  * @fb_helper: fb helper instance to use as template
1106  * @fb_width: desired fb width
1107  * @fb_height: desired fb height
1108  *
1109  * Sets up the variable fbdev metainformation from the given fb helper instance
1110  * and the drm framebuffer allocated in fb_helper->fb.
1111  *
1112  * Drivers should call this (or their equivalent setup code) from their
1113  * ->fb_probe callback after having allocated the fbdev backing
1114  * storage framebuffer.
1115  */
1116 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
1117                             uint32_t fb_width, uint32_t fb_height)
1118 {
1119         struct drm_framebuffer *fb = fb_helper->fb;
1120         info->pseudo_palette = fb_helper->pseudo_palette;
1121         info->var.xres_virtual = fb->width;
1122         info->var.yres_virtual = fb->height;
1123         info->var.bits_per_pixel = fb->bits_per_pixel;
1124         info->var.accel_flags = FB_ACCELF_TEXT;
1125         info->var.xoffset = 0;
1126         info->var.yoffset = 0;
1127         info->var.activate = FB_ACTIVATE_NOW;
1128         info->var.height = -1;
1129         info->var.width = -1;
1130
1131         switch (fb->depth) {
1132         case 8:
1133                 info->var.red.offset = 0;
1134                 info->var.green.offset = 0;
1135                 info->var.blue.offset = 0;
1136                 info->var.red.length = 8; /* 8bit DAC */
1137                 info->var.green.length = 8;
1138                 info->var.blue.length = 8;
1139                 info->var.transp.offset = 0;
1140                 info->var.transp.length = 0;
1141                 break;
1142         case 15:
1143                 info->var.red.offset = 10;
1144                 info->var.green.offset = 5;
1145                 info->var.blue.offset = 0;
1146                 info->var.red.length = 5;
1147                 info->var.green.length = 5;
1148                 info->var.blue.length = 5;
1149                 info->var.transp.offset = 15;
1150                 info->var.transp.length = 1;
1151                 break;
1152         case 16:
1153                 info->var.red.offset = 11;
1154                 info->var.green.offset = 5;
1155                 info->var.blue.offset = 0;
1156                 info->var.red.length = 5;
1157                 info->var.green.length = 6;
1158                 info->var.blue.length = 5;
1159                 info->var.transp.offset = 0;
1160                 break;
1161         case 24:
1162                 info->var.red.offset = 16;
1163                 info->var.green.offset = 8;
1164                 info->var.blue.offset = 0;
1165                 info->var.red.length = 8;
1166                 info->var.green.length = 8;
1167                 info->var.blue.length = 8;
1168                 info->var.transp.offset = 0;
1169                 info->var.transp.length = 0;
1170                 break;
1171         case 32:
1172                 info->var.red.offset = 16;
1173                 info->var.green.offset = 8;
1174                 info->var.blue.offset = 0;
1175                 info->var.red.length = 8;
1176                 info->var.green.length = 8;
1177                 info->var.blue.length = 8;
1178                 info->var.transp.offset = 24;
1179                 info->var.transp.length = 8;
1180                 break;
1181         default:
1182                 break;
1183         }
1184
1185         info->var.xres = fb_width;
1186         info->var.yres = fb_height;
1187 }
1188 EXPORT_SYMBOL(drm_fb_helper_fill_var);
1189
1190 static int drm_fb_helper_probe_connector_modes(struct drm_fb_helper *fb_helper,
1191                                                uint32_t maxX,
1192                                                uint32_t maxY)
1193 {
1194         struct drm_connector *connector;
1195         int count = 0;
1196         int i;
1197
1198         for (i = 0; i < fb_helper->connector_count; i++) {
1199                 connector = fb_helper->connector_info[i]->connector;
1200                 count += connector->funcs->fill_modes(connector, maxX, maxY);
1201         }
1202
1203         return count;
1204 }
1205
1206 struct drm_display_mode *drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector, int width, int height)
1207 {
1208         struct drm_display_mode *mode;
1209
1210         list_for_each_entry(mode, &fb_connector->connector->modes, head) {
1211                 if (mode->hdisplay > width ||
1212                     mode->vdisplay > height)
1213                         continue;
1214                 if (mode->type & DRM_MODE_TYPE_PREFERRED)
1215                         return mode;
1216         }
1217         return NULL;
1218 }
1219 EXPORT_SYMBOL(drm_has_preferred_mode);
1220
1221 static bool drm_has_cmdline_mode(struct drm_fb_helper_connector *fb_connector)
1222 {
1223         return fb_connector->connector->cmdline_mode.specified;
1224 }
1225
1226 struct drm_display_mode *drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
1227                                                       int width, int height)
1228 {
1229         struct drm_cmdline_mode *cmdline_mode;
1230         struct drm_display_mode *mode = NULL;
1231         bool prefer_non_interlace;
1232
1233         cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1234         if (cmdline_mode->specified == false)
1235                 return mode;
1236
1237         /* attempt to find a matching mode in the list of modes
1238          *  we have gotten so far, if not add a CVT mode that conforms
1239          */
1240         if (cmdline_mode->rb || cmdline_mode->margins)
1241                 goto create_mode;
1242
1243         prefer_non_interlace = !cmdline_mode->interlace;
1244  again:
1245         list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1246                 /* check width/height */
1247                 if (mode->hdisplay != cmdline_mode->xres ||
1248                     mode->vdisplay != cmdline_mode->yres)
1249                         continue;
1250
1251                 if (cmdline_mode->refresh_specified) {
1252                         if (mode->vrefresh != cmdline_mode->refresh)
1253                                 continue;
1254                 }
1255
1256                 if (cmdline_mode->interlace) {
1257                         if (!(mode->flags & DRM_MODE_FLAG_INTERLACE))
1258                                 continue;
1259                 } else if (prefer_non_interlace) {
1260                         if (mode->flags & DRM_MODE_FLAG_INTERLACE)
1261                                 continue;
1262                 }
1263                 return mode;
1264         }
1265
1266         if (prefer_non_interlace) {
1267                 prefer_non_interlace = false;
1268                 goto again;
1269         }
1270
1271 create_mode:
1272         mode = drm_mode_create_from_cmdline_mode(fb_helper_conn->connector->dev,
1273                                                  cmdline_mode);
1274         list_add(&mode->head, &fb_helper_conn->connector->modes);
1275         return mode;
1276 }
1277 EXPORT_SYMBOL(drm_pick_cmdline_mode);
1278
1279 static bool drm_connector_enabled(struct drm_connector *connector, bool strict)
1280 {
1281         bool enable;
1282
1283         if (strict)
1284                 enable = connector->status == connector_status_connected;
1285         else
1286                 enable = connector->status != connector_status_disconnected;
1287
1288         return enable;
1289 }
1290
1291 static void drm_enable_connectors(struct drm_fb_helper *fb_helper,
1292                                   bool *enabled)
1293 {
1294         bool any_enabled = false;
1295         struct drm_connector *connector;
1296         int i = 0;
1297
1298         for (i = 0; i < fb_helper->connector_count; i++) {
1299                 connector = fb_helper->connector_info[i]->connector;
1300                 enabled[i] = drm_connector_enabled(connector, true);
1301                 DRM_DEBUG_KMS("connector %d enabled? %s\n", connector->base.id,
1302                           enabled[i] ? "yes" : "no");
1303                 any_enabled |= enabled[i];
1304         }
1305
1306         if (any_enabled)
1307                 return;
1308
1309         for (i = 0; i < fb_helper->connector_count; i++) {
1310                 connector = fb_helper->connector_info[i]->connector;
1311                 enabled[i] = drm_connector_enabled(connector, false);
1312         }
1313 }
1314
1315 static bool drm_target_cloned(struct drm_fb_helper *fb_helper,
1316                               struct drm_display_mode **modes,
1317                               struct drm_fb_offset *offsets,
1318                               bool *enabled, int width, int height)
1319 {
1320         int count, i, j;
1321         bool can_clone = false;
1322         struct drm_fb_helper_connector *fb_helper_conn;
1323         struct drm_display_mode *dmt_mode, *mode;
1324
1325         /* only contemplate cloning in the single crtc case */
1326         if (fb_helper->crtc_count > 1)
1327                 return false;
1328
1329         count = 0;
1330         for (i = 0; i < fb_helper->connector_count; i++) {
1331                 if (enabled[i])
1332                         count++;
1333         }
1334
1335         /* only contemplate cloning if more than one connector is enabled */
1336         if (count <= 1)
1337                 return false;
1338
1339         /* check the command line or if nothing common pick 1024x768 */
1340         can_clone = true;
1341         for (i = 0; i < fb_helper->connector_count; i++) {
1342                 if (!enabled[i])
1343                         continue;
1344                 fb_helper_conn = fb_helper->connector_info[i];
1345                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1346                 if (!modes[i]) {
1347                         can_clone = false;
1348                         break;
1349                 }
1350                 for (j = 0; j < i; j++) {
1351                         if (!enabled[j])
1352                                 continue;
1353                         if (!drm_mode_equal(modes[j], modes[i]))
1354                                 can_clone = false;
1355                 }
1356         }
1357
1358         if (can_clone) {
1359                 DRM_DEBUG_KMS("can clone using command line\n");
1360                 return true;
1361         }
1362
1363         /* try and find a 1024x768 mode on each connector */
1364         can_clone = true;
1365         dmt_mode = drm_mode_find_dmt(fb_helper->dev, 1024, 768, 60, false);
1366
1367         for (i = 0; i < fb_helper->connector_count; i++) {
1368
1369                 if (!enabled[i])
1370                         continue;
1371
1372                 fb_helper_conn = fb_helper->connector_info[i];
1373                 list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1374                         if (drm_mode_equal(mode, dmt_mode))
1375                                 modes[i] = mode;
1376                 }
1377                 if (!modes[i])
1378                         can_clone = false;
1379         }
1380
1381         if (can_clone) {
1382                 DRM_DEBUG_KMS("can clone using 1024x768\n");
1383                 return true;
1384         }
1385         DRM_INFO("kms: can't enable cloning when we probably wanted to.\n");
1386         return false;
1387 }
1388
1389 static int drm_get_tile_offsets(struct drm_fb_helper *fb_helper,
1390                                 struct drm_display_mode **modes,
1391                                 struct drm_fb_offset *offsets,
1392                                 int idx,
1393                                 int h_idx, int v_idx)
1394 {
1395         struct drm_fb_helper_connector *fb_helper_conn;
1396         int i;
1397         int hoffset = 0, voffset = 0;
1398
1399         for (i = 0; i < fb_helper->connector_count; i++) {
1400                 fb_helper_conn = fb_helper->connector_info[i];
1401                 if (!fb_helper_conn->connector->has_tile)
1402                         continue;
1403
1404                 if (!modes[i] && (h_idx || v_idx)) {
1405                         DRM_DEBUG_KMS("no modes for connector tiled %d %d\n", i,
1406                                       fb_helper_conn->connector->base.id);
1407                         continue;
1408                 }
1409                 if (fb_helper_conn->connector->tile_h_loc < h_idx)
1410                         hoffset += modes[i]->hdisplay;
1411
1412                 if (fb_helper_conn->connector->tile_v_loc < v_idx)
1413                         voffset += modes[i]->vdisplay;
1414         }
1415         offsets[idx].x = hoffset;
1416         offsets[idx].y = voffset;
1417         DRM_DEBUG_KMS("returned %d %d for %d %d\n", hoffset, voffset, h_idx, v_idx);
1418         return 0;
1419 }
1420
1421 static bool drm_target_preferred(struct drm_fb_helper *fb_helper,
1422                                  struct drm_display_mode **modes,
1423                                  struct drm_fb_offset *offsets,
1424                                  bool *enabled, int width, int height)
1425 {
1426         struct drm_fb_helper_connector *fb_helper_conn;
1427         int i;
1428         uint64_t conn_configured = 0, mask;
1429         int tile_pass = 0;
1430         mask = (1 << fb_helper->connector_count) - 1;
1431 retry:
1432         for (i = 0; i < fb_helper->connector_count; i++) {
1433                 fb_helper_conn = fb_helper->connector_info[i];
1434
1435                 if (conn_configured & (1 << i))
1436                         continue;
1437
1438                 if (enabled[i] == false) {
1439                         conn_configured |= (1 << i);
1440                         continue;
1441                 }
1442
1443                 /* first pass over all the untiled connectors */
1444                 if (tile_pass == 0 && fb_helper_conn->connector->has_tile)
1445                         continue;
1446
1447                 if (tile_pass == 1) {
1448                         if (fb_helper_conn->connector->tile_h_loc != 0 ||
1449                             fb_helper_conn->connector->tile_v_loc != 0)
1450                                 continue;
1451
1452                 } else {
1453                         if (fb_helper_conn->connector->tile_h_loc != tile_pass -1 &&
1454                             fb_helper_conn->connector->tile_v_loc != tile_pass - 1)
1455                         /* if this tile_pass doesn't cover any of the tiles - keep going */
1456                                 continue;
1457
1458                         /* find the tile offsets for this pass - need
1459                            to find all tiles left and above */
1460                         drm_get_tile_offsets(fb_helper, modes, offsets,
1461                                              i, fb_helper_conn->connector->tile_h_loc, fb_helper_conn->connector->tile_v_loc);
1462                 }
1463                 DRM_DEBUG_KMS("looking for cmdline mode on connector %d\n",
1464                               fb_helper_conn->connector->base.id);
1465
1466                 /* got for command line mode first */
1467                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1468                 if (!modes[i]) {
1469                         DRM_DEBUG_KMS("looking for preferred mode on connector %d %d\n",
1470                                       fb_helper_conn->connector->base.id, fb_helper_conn->connector->tile_group ? fb_helper_conn->connector->tile_group->id : 0);
1471                         modes[i] = drm_has_preferred_mode(fb_helper_conn, width, height);
1472                 }
1473                 /* No preferred modes, pick one off the list */
1474                 if (!modes[i] && !list_empty(&fb_helper_conn->connector->modes)) {
1475                         list_for_each_entry(modes[i], &fb_helper_conn->connector->modes, head)
1476                                 break;
1477                 }
1478                 DRM_DEBUG_KMS("found mode %s\n", modes[i] ? modes[i]->name :
1479                           "none");
1480                 conn_configured |= (1 << i);
1481         }
1482
1483         if ((conn_configured & mask) != mask) {
1484                 tile_pass++;
1485                 goto retry;
1486         }
1487         return true;
1488 }
1489
1490 static int drm_pick_crtcs(struct drm_fb_helper *fb_helper,
1491                           struct drm_fb_helper_crtc **best_crtcs,
1492                           struct drm_display_mode **modes,
1493                           int n, int width, int height)
1494 {
1495         int c, o;
1496         struct drm_device *dev = fb_helper->dev;
1497         struct drm_connector *connector;
1498         struct drm_connector_helper_funcs *connector_funcs;
1499         struct drm_encoder *encoder;
1500         int my_score, best_score, score;
1501         struct drm_fb_helper_crtc **crtcs, *crtc;
1502         struct drm_fb_helper_connector *fb_helper_conn;
1503
1504         if (n == fb_helper->connector_count)
1505                 return 0;
1506
1507         fb_helper_conn = fb_helper->connector_info[n];
1508         connector = fb_helper_conn->connector;
1509
1510         best_crtcs[n] = NULL;
1511         best_score = drm_pick_crtcs(fb_helper, best_crtcs, modes, n+1, width, height);
1512         if (modes[n] == NULL)
1513                 return best_score;
1514
1515         crtcs = kzalloc(dev->mode_config.num_connector *
1516                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1517         if (!crtcs)
1518                 return best_score;
1519
1520         my_score = 1;
1521         if (connector->status == connector_status_connected)
1522                 my_score++;
1523         if (drm_has_cmdline_mode(fb_helper_conn))
1524                 my_score++;
1525         if (drm_has_preferred_mode(fb_helper_conn, width, height))
1526                 my_score++;
1527
1528         connector_funcs = connector->helper_private;
1529         encoder = connector_funcs->best_encoder(connector);
1530         if (!encoder)
1531                 goto out;
1532
1533         /* select a crtc for this connector and then attempt to configure
1534            remaining connectors */
1535         for (c = 0; c < fb_helper->crtc_count; c++) {
1536                 crtc = &fb_helper->crtc_info[c];
1537
1538                 if ((encoder->possible_crtcs & (1 << c)) == 0)
1539                         continue;
1540
1541                 for (o = 0; o < n; o++)
1542                         if (best_crtcs[o] == crtc)
1543                                 break;
1544
1545                 if (o < n) {
1546                         /* ignore cloning unless only a single crtc */
1547                         if (fb_helper->crtc_count > 1)
1548                                 continue;
1549
1550                         if (!drm_mode_equal(modes[o], modes[n]))
1551                                 continue;
1552                 }
1553
1554                 crtcs[n] = crtc;
1555                 memcpy(crtcs, best_crtcs, n * sizeof(struct drm_fb_helper_crtc *));
1556                 score = my_score + drm_pick_crtcs(fb_helper, crtcs, modes, n + 1,
1557                                                   width, height);
1558                 if (score > best_score) {
1559                         best_score = score;
1560                         memcpy(best_crtcs, crtcs,
1561                                dev->mode_config.num_connector *
1562                                sizeof(struct drm_fb_helper_crtc *));
1563                 }
1564         }
1565 out:
1566         kfree(crtcs);
1567         return best_score;
1568 }
1569
1570 static void drm_setup_crtcs(struct drm_fb_helper *fb_helper)
1571 {
1572         struct drm_device *dev = fb_helper->dev;
1573         struct drm_fb_helper_crtc **crtcs;
1574         struct drm_display_mode **modes;
1575         struct drm_fb_offset *offsets;
1576         struct drm_mode_set *modeset;
1577         bool *enabled;
1578         int width, height;
1579         int i;
1580
1581         DRM_DEBUG_KMS("\n");
1582
1583         width = dev->mode_config.max_width;
1584         height = dev->mode_config.max_height;
1585
1586         crtcs = kcalloc(dev->mode_config.num_connector,
1587                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1588         modes = kcalloc(dev->mode_config.num_connector,
1589                         sizeof(struct drm_display_mode *), GFP_KERNEL);
1590         offsets = kcalloc(dev->mode_config.num_connector,
1591                           sizeof(struct drm_fb_offset), GFP_KERNEL);
1592         enabled = kcalloc(dev->mode_config.num_connector,
1593                           sizeof(bool), GFP_KERNEL);
1594         if (!crtcs || !modes || !enabled || !offsets) {
1595                 DRM_ERROR("Memory allocation failed\n");
1596                 goto out;
1597         }
1598
1599
1600         drm_enable_connectors(fb_helper, enabled);
1601
1602         if (!(fb_helper->funcs->initial_config &&
1603               fb_helper->funcs->initial_config(fb_helper, crtcs, modes,
1604                                                offsets,
1605                                                enabled, width, height))) {
1606                 memset(modes, 0, dev->mode_config.num_connector*sizeof(modes[0]));
1607                 memset(crtcs, 0, dev->mode_config.num_connector*sizeof(crtcs[0]));
1608                 memset(offsets, 0, dev->mode_config.num_connector*sizeof(offsets[0]));
1609
1610                 if (!drm_target_cloned(fb_helper, modes, offsets,
1611                                        enabled, width, height) &&
1612                     !drm_target_preferred(fb_helper, modes, offsets,
1613                                           enabled, width, height))
1614                         DRM_ERROR("Unable to find initial modes\n");
1615
1616                 DRM_DEBUG_KMS("picking CRTCs for %dx%d config\n",
1617                               width, height);
1618
1619                 drm_pick_crtcs(fb_helper, crtcs, modes, 0, width, height);
1620         }
1621
1622         /* need to set the modesets up here for use later */
1623         /* fill out the connector<->crtc mappings into the modesets */
1624         for (i = 0; i < fb_helper->crtc_count; i++) {
1625                 modeset = &fb_helper->crtc_info[i].mode_set;
1626                 modeset->num_connectors = 0;
1627                 modeset->fb = NULL;
1628         }
1629
1630         for (i = 0; i < fb_helper->connector_count; i++) {
1631                 struct drm_display_mode *mode = modes[i];
1632                 struct drm_fb_helper_crtc *fb_crtc = crtcs[i];
1633                 struct drm_fb_offset *offset = &offsets[i];
1634                 modeset = &fb_crtc->mode_set;
1635
1636                 if (mode && fb_crtc) {
1637                         DRM_DEBUG_KMS("desired mode %s set on crtc %d (%d,%d)\n",
1638                                       mode->name, fb_crtc->mode_set.crtc->base.id, offset->x, offset->y);
1639                         fb_crtc->desired_mode = mode;
1640                         fb_crtc->x = offset->x;
1641                         fb_crtc->y = offset->y;
1642                         if (modeset->mode)
1643                                 drm_mode_destroy(dev, modeset->mode);
1644                         modeset->mode = drm_mode_duplicate(dev,
1645                                                            fb_crtc->desired_mode);
1646                         modeset->connectors[modeset->num_connectors++] = fb_helper->connector_info[i]->connector;
1647                         modeset->fb = fb_helper->fb;
1648                         modeset->x = offset->x;
1649                         modeset->y = offset->y;
1650                 }
1651         }
1652
1653         /* Clear out any old modes if there are no more connected outputs. */
1654         for (i = 0; i < fb_helper->crtc_count; i++) {
1655                 modeset = &fb_helper->crtc_info[i].mode_set;
1656                 if (modeset->num_connectors == 0) {
1657                         BUG_ON(modeset->fb);
1658                         if (modeset->mode)
1659                                 drm_mode_destroy(dev, modeset->mode);
1660                         modeset->mode = NULL;
1661                 }
1662         }
1663 out:
1664         kfree(crtcs);
1665         kfree(modes);
1666         kfree(offsets);
1667         kfree(enabled);
1668 }
1669
1670 /**
1671  * drm_fb_helper_initial_config - setup a sane initial connector configuration
1672  * @fb_helper: fb_helper device struct
1673  * @bpp_sel: bpp value to use for the framebuffer configuration
1674  *
1675  * Scans the CRTCs and connectors and tries to put together an initial setup.
1676  * At the moment, this is a cloned configuration across all heads with
1677  * a new framebuffer object as the backing store.
1678  *
1679  * Note that this also registers the fbdev and so allows userspace to call into
1680  * the driver through the fbdev interfaces.
1681  *
1682  * This function will call down into the ->fb_probe callback to let
1683  * the driver allocate and initialize the fbdev info structure and the drm
1684  * framebuffer used to back the fbdev. drm_fb_helper_fill_var() and
1685  * drm_fb_helper_fill_fix() are provided as helpers to setup simple default
1686  * values for the fbdev info structure.
1687  *
1688  * RETURNS:
1689  * Zero if everything went ok, nonzero otherwise.
1690  */
1691 bool drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel)
1692 {
1693         struct drm_device *dev = fb_helper->dev;
1694         int count = 0;
1695
1696         mutex_lock(&dev->mode_config.mutex);
1697         count = drm_fb_helper_probe_connector_modes(fb_helper,
1698                                                     dev->mode_config.max_width,
1699                                                     dev->mode_config.max_height);
1700         mutex_unlock(&dev->mode_config.mutex);
1701         /*
1702          * we shouldn't end up with no modes here.
1703          */
1704         if (count == 0)
1705                 dev_info(fb_helper->dev->dev, "No connectors reported connected with modes\n");
1706
1707         drm_setup_crtcs(fb_helper);
1708
1709         return drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
1710 }
1711 EXPORT_SYMBOL(drm_fb_helper_initial_config);
1712
1713 /**
1714  * drm_fb_helper_hotplug_event - respond to a hotplug notification by
1715  *                               probing all the outputs attached to the fb
1716  * @fb_helper: the drm_fb_helper
1717  *
1718  * Scan the connectors attached to the fb_helper and try to put together a
1719  * setup after *notification of a change in output configuration.
1720  *
1721  * Called at runtime, takes the mode config locks to be able to check/change the
1722  * modeset configuration. Must be run from process context (which usually means
1723  * either the output polling work or a work item launched from the driver's
1724  * hotplug interrupt).
1725  *
1726  * Note that drivers may call this even before calling
1727  * drm_fb_helper_initial_config but only aftert drm_fb_helper_init. This allows
1728  * for a race-free fbcon setup and will make sure that the fbdev emulation will
1729  * not miss any hotplug events.
1730  *
1731  * RETURNS:
1732  * 0 on success and a non-zero error code otherwise.
1733  */
1734 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
1735 {
1736         struct drm_device *dev = fb_helper->dev;
1737         u32 max_width, max_height;
1738
1739         mutex_lock(&fb_helper->dev->mode_config.mutex);
1740         if (!fb_helper->fb || !drm_fb_helper_is_bound(fb_helper)) {
1741                 fb_helper->delayed_hotplug = true;
1742                 mutex_unlock(&fb_helper->dev->mode_config.mutex);
1743                 return 0;
1744         }
1745         DRM_DEBUG_KMS("\n");
1746
1747         max_width = fb_helper->fb->width;
1748         max_height = fb_helper->fb->height;
1749
1750         drm_fb_helper_probe_connector_modes(fb_helper, max_width, max_height);
1751         mutex_unlock(&fb_helper->dev->mode_config.mutex);
1752
1753         drm_modeset_lock_all(dev);
1754         drm_setup_crtcs(fb_helper);
1755         drm_modeset_unlock_all(dev);
1756         drm_fb_helper_set_par(fb_helper->fbdev);
1757
1758         return 0;
1759 }
1760 EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
1761
1762 /* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
1763  * but the module doesn't depend on any fb console symbols.  At least
1764  * attempt to load fbcon to avoid leaving the system without a usable console.
1765  */
1766 #if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT)
1767 static int __init drm_fb_helper_modinit(void)
1768 {
1769         const char *name = "fbcon";
1770         struct module *fbcon;
1771
1772         mutex_lock(&module_mutex);
1773         fbcon = find_module(name);
1774         mutex_unlock(&module_mutex);
1775
1776         if (!fbcon)
1777                 request_module_nowait(name);
1778         return 0;
1779 }
1780
1781 module_init(drm_fb_helper_modinit);
1782 #endif