drivers/base/firmware_class.c

   1 /*
   2  * firmware_class.c - Multi purpose firmware loading support
   3  *
   4  * Copyright (c) 2003 Manuel Estrada Sainz
   5  *
   6  * Please see Documentation/firmware_class/ for more information.
   7  *
   8  */
   9
  10 #include <linux/capability.h>
  11 #include <linux/device.h>
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/timer.h>
  15 #include <linux/vmalloc.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/bitops.h>
  18 #include <linux/mutex.h>
  19 #include <linux/workqueue.h>
  20 #include <linux/highmem.h>
  21 #include <linux/firmware.h>
  22 #include <linux/slab.h>
  23 #include <linux/sched.h>
  24 #include <linux/file.h>
  25 #include <linux/list.h>
  26 #include <linux/async.h>
  27 #include <linux/pm.h>
  28 #include <linux/suspend.h>
  29 #include <linux/syscore_ops.h>
  30
  31 #include <generated/utsrelease.h>
  32
  33 #include "base.h"
  34
  35 MODULE_AUTHOR("Manuel Estrada Sainz");
  36 MODULE_DESCRIPTION("Multi purpose firmware loading support");
  37 MODULE_LICENSE("GPL");
  38
  39 /* Builtin firmware support */
  40
  41 #ifdef CONFIG_FW_LOADER
  42
  43 extern struct builtin_fw __start_builtin_fw[];
  44 extern struct builtin_fw __end_builtin_fw[];
  45
  46 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  47 {
  48         struct builtin_fw *b_fw;
  49
  50         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
  51                 if (strcmp(name, b_fw->name) == 0) {
  52                         fw->size = b_fw->size;
  53                         fw->data = b_fw->data;
  54                         return true;
  55                 }
  56         }
  57
  58         return false;
  59 }
  60
  61 static bool fw_is_builtin_firmware(const struct firmware *fw)
  62 {
  63         struct builtin_fw *b_fw;
  64
  65         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
  66                 if (fw->data == b_fw->data)
  67                         return true;
  68
  69         return false;
  70 }
  71
  72 #else /* Module case - no builtin firmware support */
  73
  74 static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  75 {
  76         return false;
  77 }
  78
  79 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
  80 {
  81         return false;
  82 }
  83 #endif
  84
  85 enum {
  86         FW_STATUS_LOADING,
  87         FW_STATUS_DONE,
  88         FW_STATUS_ABORT,
  89 };
  90
  91 enum fw_buf_fmt {
  92         VMALLOC_BUF,    /* used in direct loading */
  93         PAGE_BUF,       /* used in loading via userspace */
  94 };
  95
  96 static int loading_timeout = 60;        /* In seconds */
  97
  98 static inline long firmware_loading_timeout(void)
  99 {
 100         return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
 101 }
 102
 103 struct firmware_cache {
 104         /* firmware_buf instance will be added into the below list */
 105         spinlock_t lock;
 106         struct list_head head;
 107         int state;
 108
 109 #ifdef CONFIG_PM_SLEEP
 110         /*
 111          * Names of firmware images which have been cached successfully
 112          * will be added into the below list so that device uncache
 113          * helper can trace which firmware images have been cached
 114          * before.
 115          */
 116         spinlock_t name_lock;
 117         struct list_head fw_names;
 118
 119         struct delayed_work work;
 120
 121         struct notifier_block   pm_notify;
 122 #endif
 123 };
 124
 125 struct firmware_buf {
 126         struct kref ref;
 127         struct list_head list;
 128         struct completion completion;
 129         struct firmware_cache *fwc;
 130         unsigned long status;
 131         enum fw_buf_fmt fmt;
 132         void *data;
 133         size_t size;
 134         struct page **pages;
 135         int nr_pages;
 136         int page_array_size;
 137         char fw_id[];
 138 };
 139
 140 struct fw_cache_entry {
 141         struct list_head list;
 142         char name[];
 143 };
 144
 145 struct firmware_priv {
 146         struct timer_list timeout;
 147         bool nowait;
 148         struct device dev;
 149         struct firmware_buf *buf;
 150         struct firmware *fw;
 151 };
 152
 153 struct fw_name_devm {
 154         unsigned long magic;
 155         char name[];
 156 };
 157
 158 #define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
 159
 160 #define FW_LOADER_NO_CACHE      0
 161 #define FW_LOADER_START_CACHE   1
 162
 163 static int fw_cache_piggyback_on_request(const char *name);
 164
 165 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
 166  * guarding for corner cases a global lock should be OK */
 167 static DEFINE_MUTEX(fw_lock);
 168
 169 static struct firmware_cache fw_cache;
 170
 171 static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
 172                                               struct firmware_cache *fwc)
 173 {
 174         struct firmware_buf *buf;
 175
 176         buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1 , GFP_ATOMIC);
 177
 178         if (!buf)
 179                 return buf;
 180
 181         kref_init(&buf->ref);
 182         strcpy(buf->fw_id, fw_name);
 183         buf->fwc = fwc;
 184         init_completion(&buf->completion);
 185         buf->fmt = VMALLOC_BUF;
 186
 187         pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
 188
 189         return buf;
 190 }
 191
 192 static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
 193 {
 194         struct firmware_buf *tmp;
 195         struct firmware_cache *fwc = &fw_cache;
 196
 197         list_for_each_entry(tmp, &fwc->head, list)
 198                 if (!strcmp(tmp->fw_id, fw_name))
 199                         return tmp;
 200         return NULL;
 201 }
 202
 203 static int fw_lookup_and_allocate_buf(const char *fw_name,
 204                                       struct firmware_cache *fwc,
 205                                       struct firmware_buf **buf)
 206 {
 207         struct firmware_buf *tmp;
 208
 209         spin_lock(&fwc->lock);
 210         tmp = __fw_lookup_buf(fw_name);
 211         if (tmp) {
 212                 kref_get(&tmp->ref);
 213                 spin_unlock(&fwc->lock);
 214                 *buf = tmp;
 215                 return 1;
 216         }
 217         tmp = __allocate_fw_buf(fw_name, fwc);
 218         if (tmp)
 219                 list_add(&tmp->list, &fwc->head);
 220         spin_unlock(&fwc->lock);
 221
 222         *buf = tmp;
 223
 224         return tmp ? 0 : -ENOMEM;
 225 }
 226
 227 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
 228 {
 229         struct firmware_buf *tmp;
 230         struct firmware_cache *fwc = &fw_cache;
 231
 232         spin_lock(&fwc->lock);
 233         tmp = __fw_lookup_buf(fw_name);
 234         spin_unlock(&fwc->lock);
 235
 236         return tmp;
 237 }
 238
 239 static void __fw_free_buf(struct kref *ref)
 240 {
 241         struct firmware_buf *buf = to_fwbuf(ref);
 242         struct firmware_cache *fwc = buf->fwc;
 243         int i;
 244
 245         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 246                  __func__, buf->fw_id, buf, buf->data,
 247                  (unsigned int)buf->size);
 248
 249         spin_lock(&fwc->lock);
 250         list_del(&buf->list);
 251         spin_unlock(&fwc->lock);
 252
 253
 254         if (buf->fmt == PAGE_BUF) {
 255                 vunmap(buf->data);
 256                 for (i = 0; i < buf->nr_pages; i++)
 257                         __free_page(buf->pages[i]);
 258                 kfree(buf->pages);
 259         } else
 260                 vfree(buf->data);
 261         kfree(buf);
 262 }
 263
 264 static void fw_free_buf(struct firmware_buf *buf)
 265 {
 266         kref_put(&buf->ref, __fw_free_buf);
 267 }
 268
 269 /* direct firmware loading support */
 270 static const char *fw_path[] = {
 271         "/lib/firmware/updates/" UTS_RELEASE,
 272         "/lib/firmware/updates",
 273         "/lib/firmware/" UTS_RELEASE,
 274         "/lib/firmware"
 275 };
 276
 277 /* Don't inline this: 'struct kstat' is biggish */
 278 static noinline long fw_file_size(struct file *file)
 279 {
 280         struct kstat st;
 281         if (vfs_getattr(file->f_path.mnt, file->f_path.dentry, &st))
 282                 return -1;
 283         if (!S_ISREG(st.mode))
 284                 return -1;
 285         if (st.size != (long)st.size)
 286                 return -1;
 287         return st.size;
 288 }
 289
 290 static bool fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
 291 {
 292         long size;
 293         char *buf;
 294
 295         size = fw_file_size(file);
 296         if (size < 0)
 297                 return false;
 298         buf = vmalloc(size);
 299         if (!buf)
 300                 return false;
 301         if (kernel_read(file, 0, buf, size) != size) {
 302                 vfree(buf);
 303                 return false;
 304         }
 305         fw_buf->data = buf;
 306         fw_buf->size = size;
 307         return true;
 308 }
 309
 310 static bool fw_get_filesystem_firmware(struct firmware_buf *buf)
 311 {
 312         int i;
 313         bool success = false;
 314         char *path = __getname();
 315
 316         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 317                 struct file *file;
 318                 snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
 319
 320                 file = filp_open(path, O_RDONLY, 0);
 321                 if (IS_ERR(file))
 322                         continue;
 323                 success = fw_read_file_contents(file, buf);
 324                 fput(file);
 325                 if (success)
 326                         break;
 327         }
 328         __putname(path);
 329         return success;
 330 }
 331
 332 static struct firmware_priv *to_firmware_priv(struct device *dev)
 333 {
 334         return container_of(dev, struct firmware_priv, dev);
 335 }
 336
 337 static void fw_load_abort(struct firmware_priv *fw_priv)
 338 {
 339         struct firmware_buf *buf = fw_priv->buf;
 340
 341         set_bit(FW_STATUS_ABORT, &buf->status);
 342         complete_all(&buf->completion);
 343 }
 344
 345 static ssize_t firmware_timeout_show(struct class *class,
 346                                      struct class_attribute *attr,
 347                                      char *buf)
 348 {
 349         return sprintf(buf, "%d\n", loading_timeout);
 350 }
 351
 352 /**
 353  * firmware_timeout_store - set number of seconds to wait for firmware
 354  * @class: device class pointer
 355  * @attr: device attribute pointer
 356  * @buf: buffer to scan for timeout value
 357  * @count: number of bytes in @buf
 358  *
 359  *      Sets the number of seconds to wait for the firmware.  Once
 360  *      this expires an error will be returned to the driver and no
 361  *      firmware will be provided.
 362  *
 363  *      Note: zero means 'wait forever'.
 364  **/
 365 static ssize_t firmware_timeout_store(struct class *class,
 366                                       struct class_attribute *attr,
 367                                       const char *buf, size_t count)
 368 {
 369         loading_timeout = simple_strtol(buf, NULL, 10);
 370         if (loading_timeout < 0)
 371                 loading_timeout = 0;
 372
 373         return count;
 374 }
 375
 376 static struct class_attribute firmware_class_attrs[] = {
 377         __ATTR(timeout, S_IWUSR | S_IRUGO,
 378                 firmware_timeout_show, firmware_timeout_store),
 379         __ATTR_NULL
 380 };
 381
 382 static void fw_dev_release(struct device *dev)
 383 {
 384         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 385
 386         kfree(fw_priv);
 387
 388         module_put(THIS_MODULE);
 389 }
 390
 391 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 392 {
 393         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 394
 395         if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
 396                 return -ENOMEM;
 397         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
 398                 return -ENOMEM;
 399         if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
 400                 return -ENOMEM;
 401
 402         return 0;
 403 }
 404
 405 static struct class firmware_class = {
 406         .name           = "firmware",
 407         .class_attrs    = firmware_class_attrs,
 408         .dev_uevent     = firmware_uevent,
 409         .dev_release    = fw_dev_release,
 410 };
 411
 412 static ssize_t firmware_loading_show(struct device *dev,
 413                                      struct device_attribute *attr, char *buf)
 414 {
 415         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 416         int loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
 417
 418         return sprintf(buf, "%d\n", loading);
 419 }
 420
 421 /* firmware holds the ownership of pages */
 422 static void firmware_free_data(const struct firmware *fw)
 423 {
 424         /* Loaded directly? */
 425         if (!fw->priv) {
 426                 vfree(fw->data);
 427                 return;
 428         }
 429         fw_free_buf(fw->priv);
 430 }
 431
 432 /* Some architectures don't have PAGE_KERNEL_RO */
 433 #ifndef PAGE_KERNEL_RO
 434 #define PAGE_KERNEL_RO PAGE_KERNEL
 435 #endif
 436
 437 /* one pages buffer should be mapped/unmapped only once */
 438 static int fw_map_pages_buf(struct firmware_buf *buf)
 439 {
 440         if (buf->fmt != PAGE_BUF)
 441                 return 0;
 442
 443         if (buf->data)
 444                 vunmap(buf->data);
 445         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 446         if (!buf->data)
 447                 return -ENOMEM;
 448         return 0;
 449 }
 450
 451 /**
 452  * firmware_loading_store - set value in the 'loading' control file
 453  * @dev: device pointer
 454  * @attr: device attribute pointer
 455  * @buf: buffer to scan for loading control value
 456  * @count: number of bytes in @buf
 457  *
 458  *      The relevant values are:
 459  *
 460  *       1: Start a load, discarding any previous partial load.
 461  *       0: Conclude the load and hand the data to the driver code.
 462  *      -1: Conclude the load with an error and discard any written data.
 463  **/
 464 static ssize_t firmware_loading_store(struct device *dev,
 465                                       struct device_attribute *attr,
 466                                       const char *buf, size_t count)
 467 {
 468         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 469         struct firmware_buf *fw_buf = fw_priv->buf;
 470         int loading = simple_strtol(buf, NULL, 10);
 471         int i;
 472
 473         mutex_lock(&fw_lock);
 474
 475         if (!fw_buf)
 476                 goto out;
 477
 478         switch (loading) {
 479         case 1:
 480                 /* discarding any previous partial load */
 481                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
 482                         for (i = 0; i < fw_buf->nr_pages; i++)
 483                                 __free_page(fw_buf->pages[i]);
 484                         kfree(fw_buf->pages);
 485                         fw_buf->pages = NULL;
 486                         fw_buf->page_array_size = 0;
 487                         fw_buf->nr_pages = 0;
 488                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
 489                 }
 490                 break;
 491         case 0:
 492                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
 493                         set_bit(FW_STATUS_DONE, &fw_buf->status);
 494                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
 495
 496                         /*
 497                          * Several loading requests may be pending on
 498                          * one same firmware buf, so let all requests
 499                          * see the mapped 'buf->data' once the loading
 500                          * is completed.
 501                          * */
 502                         fw_map_pages_buf(fw_buf);
 503                         complete_all(&fw_buf->completion);
 504                         break;
 505                 }
 506                 /* fallthrough */
 507         default:
 508                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 509                 /* fallthrough */
 510         case -1:
 511                 fw_load_abort(fw_priv);
 512                 break;
 513         }
 514 out:
 515         mutex_unlock(&fw_lock);
 516         return count;
 517 }
 518
 519 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 520
 521 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 522                                   struct bin_attribute *bin_attr,
 523                                   char *buffer, loff_t offset, size_t count)
 524 {
 525         struct device *dev = kobj_to_dev(kobj);
 526         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 527         struct firmware_buf *buf;
 528         ssize_t ret_count;
 529
 530         mutex_lock(&fw_lock);
 531         buf = fw_priv->buf;
 532         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 533                 ret_count = -ENODEV;
 534                 goto out;
 535         }
 536         if (offset > buf->size) {
 537                 ret_count = 0;
 538                 goto out;
 539         }
 540         if (count > buf->size - offset)
 541                 count = buf->size - offset;
 542
 543         ret_count = count;
 544
 545         while (count) {
 546                 void *page_data;
 547                 int page_nr = offset >> PAGE_SHIFT;
 548                 int page_ofs = offset & (PAGE_SIZE-1);
 549                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 550
 551                 page_data = kmap(buf->pages[page_nr]);
 552
 553                 memcpy(buffer, page_data + page_ofs, page_cnt);
 554
 555                 kunmap(buf->pages[page_nr]);
 556                 buffer += page_cnt;
 557                 offset += page_cnt;
 558                 count -= page_cnt;
 559         }
 560 out:
 561         mutex_unlock(&fw_lock);
 562         return ret_count;
 563 }
 564
 565 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 566 {
 567         struct firmware_buf *buf = fw_priv->buf;
 568         int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
 569
 570         /* If the array of pages is too small, grow it... */
 571         if (buf->page_array_size < pages_needed) {
 572                 int new_array_size = max(pages_needed,
 573                                          buf->page_array_size * 2);
 574                 struct page **new_pages;
 575
 576                 new_pages = kmalloc(new_array_size * sizeof(void *),
 577                                     GFP_KERNEL);
 578                 if (!new_pages) {
 579                         fw_load_abort(fw_priv);
 580                         return -ENOMEM;
 581                 }
 582                 memcpy(new_pages, buf->pages,
 583                        buf->page_array_size * sizeof(void *));
 584                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 585                        (new_array_size - buf->page_array_size));
 586                 kfree(buf->pages);
 587                 buf->pages = new_pages;
 588                 buf->page_array_size = new_array_size;
 589         }
 590
 591         while (buf->nr_pages < pages_needed) {
 592                 buf->pages[buf->nr_pages] =
 593                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 594
 595                 if (!buf->pages[buf->nr_pages]) {
 596                         fw_load_abort(fw_priv);
 597                         return -ENOMEM;
 598                 }
 599                 buf->nr_pages++;
 600         }
 601         return 0;
 602 }
 603
 604 /**
 605  * firmware_data_write - write method for firmware
 606  * @filp: open sysfs file
 607  * @kobj: kobject for the device
 608  * @bin_attr: bin_attr structure
 609  * @buffer: buffer being written
 610  * @offset: buffer offset for write in total data store area
 611  * @count: buffer size
 612  *
 613  *      Data written to the 'data' attribute will be later handed to
 614  *      the driver as a firmware image.
 615  **/
 616 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 617                                    struct bin_attribute *bin_attr,
 618                                    char *buffer, loff_t offset, size_t count)
 619 {
 620         struct device *dev = kobj_to_dev(kobj);
 621         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 622         struct firmware_buf *buf;
 623         ssize_t retval;
 624
 625         if (!capable(CAP_SYS_RAWIO))
 626                 return -EPERM;
 627
 628         mutex_lock(&fw_lock);
 629         buf = fw_priv->buf;
 630         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 631                 retval = -ENODEV;
 632                 goto out;
 633         }
 634
 635         retval = fw_realloc_buffer(fw_priv, offset + count);
 636         if (retval)
 637                 goto out;
 638
 639         retval = count;
 640
 641         while (count) {
 642                 void *page_data;
 643                 int page_nr = offset >> PAGE_SHIFT;
 644                 int page_ofs = offset & (PAGE_SIZE - 1);
 645                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 646
 647                 page_data = kmap(buf->pages[page_nr]);
 648
 649                 memcpy(page_data + page_ofs, buffer, page_cnt);
 650
 651                 kunmap(buf->pages[page_nr]);
 652                 buffer += page_cnt;
 653                 offset += page_cnt;
 654                 count -= page_cnt;
 655         }
 656
 657         buf->size = max_t(size_t, offset, buf->size);
 658 out:
 659         mutex_unlock(&fw_lock);
 660         return retval;
 661 }
 662
 663 static struct bin_attribute firmware_attr_data = {
 664         .attr = { .name = "data", .mode = 0644 },
 665         .size = 0,
 666         .read = firmware_data_read,
 667         .write = firmware_data_write,
 668 };
 669
 670 static void firmware_class_timeout(u_long data)
 671 {
 672         struct firmware_priv *fw_priv = (struct firmware_priv *) data;
 673
 674         fw_load_abort(fw_priv);
 675 }
 676
 677 static struct firmware_priv *
 678 fw_create_instance(struct firmware *firmware, const char *fw_name,
 679                    struct device *device, bool uevent, bool nowait)
 680 {
 681         struct firmware_priv *fw_priv;
 682         struct device *f_dev;
 683
 684         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 685         if (!fw_priv) {
 686                 dev_err(device, "%s: kmalloc failed\n", __func__);
 687                 fw_priv = ERR_PTR(-ENOMEM);
 688                 goto exit;
 689         }
 690
 691         fw_priv->nowait = nowait;
 692         fw_priv->fw = firmware;
 693         setup_timer(&fw_priv->timeout,
 694                     firmware_class_timeout, (u_long) fw_priv);
 695
 696         f_dev = &fw_priv->dev;
 697
 698         device_initialize(f_dev);
 699         dev_set_name(f_dev, "%s", fw_name);
 700         f_dev->parent = device;
 701         f_dev->class = &firmware_class;
 702 exit:
 703         return fw_priv;
 704 }
 705
 706 /* store the pages buffer info firmware from buf */
 707 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
 708 {
 709         fw->priv = buf;
 710         fw->pages = buf->pages;
 711         fw->size = buf->size;
 712         fw->data = buf->data;
 713
 714         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 715                  __func__, buf->fw_id, buf, buf->data,
 716                  (unsigned int)buf->size);
 717 }
 718
 719 #ifdef CONFIG_PM_SLEEP
 720 static void fw_name_devm_release(struct device *dev, void *res)
 721 {
 722         struct fw_name_devm *fwn = res;
 723
 724         if (fwn->magic == (unsigned long)&fw_cache)
 725                 pr_debug("%s: fw_name-%s devm-%p released\n",
 726                                 __func__, fwn->name, res);
 727 }
 728
 729 static int fw_devm_match(struct device *dev, void *res,
 730                 void *match_data)
 731 {
 732         struct fw_name_devm *fwn = res;
 733
 734         return (fwn->magic == (unsigned long)&fw_cache) &&
 735                 !strcmp(fwn->name, match_data);
 736 }
 737
 738 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 739                 const char *name)
 740 {
 741         struct fw_name_devm *fwn;
 742
 743         fwn = devres_find(dev, fw_name_devm_release,
 744                           fw_devm_match, (void *)name);
 745         return fwn;
 746 }
 747
 748 /* add firmware name into devres list */
 749 static int fw_add_devm_name(struct device *dev, const char *name)
 750 {
 751         struct fw_name_devm *fwn;
 752
 753         fwn = fw_find_devm_name(dev, name);
 754         if (fwn)
 755                 return 1;
 756
 757         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
 758                            strlen(name) + 1, GFP_KERNEL);
 759         if (!fwn)
 760                 return -ENOMEM;
 761
 762         fwn->magic = (unsigned long)&fw_cache;
 763         strcpy(fwn->name, name);
 764         devres_add(dev, fwn);
 765
 766         return 0;
 767 }
 768 #else
 769 static int fw_add_devm_name(struct device *dev, const char *name)
 770 {
 771         return 0;
 772 }
 773 #endif
 774
 775 static void _request_firmware_cleanup(const struct firmware **firmware_p)
 776 {
 777         release_firmware(*firmware_p);
 778         *firmware_p = NULL;
 779 }
 780
 781 static struct firmware_priv *
 782 _request_firmware_prepare(const struct firmware **firmware_p, const char *name,
 783                           struct device *device, bool uevent, bool nowait)
 784 {
 785         struct firmware *firmware;
 786         struct firmware_priv *fw_priv = NULL;
 787         struct firmware_buf *buf;
 788         int ret;
 789
 790         if (!firmware_p)
 791                 return ERR_PTR(-EINVAL);
 792
 793         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
 794         if (!firmware) {
 795                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
 796                         __func__);
 797                 return ERR_PTR(-ENOMEM);
 798         }
 799
 800         if (fw_get_builtin_firmware(firmware, name)) {
 801                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
 802                 return NULL;
 803         }
 804
 805         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
 806         if (!ret)
 807                 fw_priv = fw_create_instance(firmware, name, device,
 808                                 uevent, nowait);
 809
 810         if (IS_ERR(fw_priv) || ret < 0) {
 811                 kfree(firmware);
 812                 *firmware_p = NULL;
 813                 return ERR_PTR(-ENOMEM);
 814         } else if (fw_priv) {
 815                 fw_priv->buf = buf;
 816
 817                 /*
 818                  * bind with 'buf' now to avoid warning in failure path
 819                  * of requesting firmware.
 820                  */
 821                 firmware->priv = buf;
 822                 return fw_priv;
 823         }
 824
 825         /* share the cached buf, which is inprogessing or completed */
 826  check_status:
 827         mutex_lock(&fw_lock);
 828         if (test_bit(FW_STATUS_ABORT, &buf->status)) {
 829                 fw_priv = ERR_PTR(-ENOENT);
 830                 firmware->priv = buf;
 831                 _request_firmware_cleanup(firmware_p);
 832                 goto exit;
 833         } else if (test_bit(FW_STATUS_DONE, &buf->status)) {
 834                 fw_priv = NULL;
 835                 fw_set_page_data(buf, firmware);
 836                 goto exit;
 837         }
 838         mutex_unlock(&fw_lock);
 839         wait_for_completion(&buf->completion);
 840         goto check_status;
 841
 842 exit:
 843         mutex_unlock(&fw_lock);
 844         return fw_priv;
 845 }
 846
 847 static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
 848                                   long timeout)
 849 {
 850         int retval = 0;
 851         struct device *f_dev = &fw_priv->dev;
 852         struct firmware_buf *buf = fw_priv->buf;
 853         struct firmware_cache *fwc = &fw_cache;
 854         int direct_load = 0;
 855
 856         /* try direct loading from fs first */
 857         if (fw_get_filesystem_firmware(buf)) {
 858                 dev_dbg(f_dev->parent, "firmware: direct-loading"
 859                         " firmware %s\n", buf->fw_id);
 860
 861                 set_bit(FW_STATUS_DONE, &buf->status);
 862                 complete_all(&buf->completion);
 863                 direct_load = 1;
 864                 goto handle_fw;
 865         }
 866
 867         /* fall back on userspace loading */
 868         buf->fmt = PAGE_BUF;
 869
 870         dev_set_uevent_suppress(f_dev, true);
 871
 872         /* Need to pin this module until class device is destroyed */
 873         __module_get(THIS_MODULE);
 874
 875         retval = device_add(f_dev);
 876         if (retval) {
 877                 dev_err(f_dev, "%s: device_register failed\n", __func__);
 878                 goto err_put_dev;
 879         }
 880
 881         retval = device_create_bin_file(f_dev, &firmware_attr_data);
 882         if (retval) {
 883                 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
 884                 goto err_del_dev;
 885         }
 886
 887         retval = device_create_file(f_dev, &dev_attr_loading);
 888         if (retval) {
 889                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
 890                 goto err_del_bin_attr;
 891         }
 892
 893         if (uevent) {
 894                 dev_set_uevent_suppress(f_dev, false);
 895                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
 896                 if (timeout != MAX_SCHEDULE_TIMEOUT)
 897                         mod_timer(&fw_priv->timeout,
 898                                   round_jiffies_up(jiffies + timeout));
 899
 900                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 901         }
 902
 903         wait_for_completion(&buf->completion);
 904
 905         del_timer_sync(&fw_priv->timeout);
 906
 907 handle_fw:
 908         mutex_lock(&fw_lock);
 909         if (!buf->size || test_bit(FW_STATUS_ABORT, &buf->status))
 910                 retval = -ENOENT;
 911
 912         /*
 913          * add firmware name into devres list so that we can auto cache
 914          * and uncache firmware for device.
 915          *
 916          * f_dev->parent may has been deleted already, but the problem
 917          * should be fixed in devres or driver core.
 918          */
 919         if (!retval && f_dev->parent)
 920                 fw_add_devm_name(f_dev->parent, buf->fw_id);
 921
 922         /*
 923          * After caching firmware image is started, let it piggyback
 924          * on request firmware.
 925          */
 926         if (!retval && fwc->state == FW_LOADER_START_CACHE) {
 927                 if (fw_cache_piggyback_on_request(buf->fw_id))
 928                         kref_get(&buf->ref);
 929         }
 930
 931         /* pass the pages buffer to driver at the last minute */
 932         fw_set_page_data(buf, fw_priv->fw);
 933
 934         fw_priv->buf = NULL;
 935         mutex_unlock(&fw_lock);
 936
 937         if (direct_load)
 938                 goto err_put_dev;
 939
 940         device_remove_file(f_dev, &dev_attr_loading);
 941 err_del_bin_attr:
 942         device_remove_bin_file(f_dev, &firmware_attr_data);
 943 err_del_dev:
 944         device_del(f_dev);
 945 err_put_dev:
 946         put_device(f_dev);
 947         return retval;
 948 }
 949
 950 /**
 951  * request_firmware: - send firmware request and wait for it
 952  * @firmware_p: pointer to firmware image
 953  * @name: name of firmware file
 954  * @device: device for which firmware is being loaded
 955  *
 956  *      @firmware_p will be used to return a firmware image by the name
 957  *      of @name for device @device.
 958  *
 959  *      Should be called from user context where sleeping is allowed.
 960  *
 961  *      @name will be used as $FIRMWARE in the uevent environment and
 962  *      should be distinctive enough not to be confused with any other
 963  *      firmware image for this or any other device.
 964  *
 965  *      Caller must hold the reference count of @device.
 966  **/
 967 int
 968 request_firmware(const struct firmware **firmware_p, const char *name,
 969                  struct device *device)
 970 {
 971         struct firmware_priv *fw_priv;
 972         int ret;
 973
 974         fw_priv = _request_firmware_prepare(firmware_p, name, device, true,
 975                                             false);
 976         if (IS_ERR_OR_NULL(fw_priv))
 977                 return PTR_RET(fw_priv);
 978
 979         ret = usermodehelper_read_trylock();
 980         if (WARN_ON(ret)) {
 981                 dev_err(device, "firmware: %s will not be loaded\n", name);
 982         } else {
 983                 ret = _request_firmware_load(fw_priv, true,
 984                                         firmware_loading_timeout());
 985                 usermodehelper_read_unlock();
 986         }
 987         if (ret)
 988                 _request_firmware_cleanup(firmware_p);
 989
 990         return ret;
 991 }
 992
 993 /**
 994  * release_firmware: - release the resource associated with a firmware image
 995  * @fw: firmware resource to release
 996  **/
 997 void release_firmware(const struct firmware *fw)
 998 {
 999         if (fw) {
1000                 if (!fw_is_builtin_firmware(fw))
1001                         firmware_free_data(fw);
1002                 kfree(fw);
1003         }
1004 }
1005
1006 /* Async support */
1007 struct firmware_work {
1008         struct work_struct work;
1009         struct module *module;
1010         const char *name;
1011         struct device *device;
1012         void *context;
1013         void (*cont)(const struct firmware *fw, void *context);
1014         bool uevent;
1015 };
1016
1017 static void request_firmware_work_func(struct work_struct *work)
1018 {
1019         struct firmware_work *fw_work;
1020         const struct firmware *fw;
1021         struct firmware_priv *fw_priv;
1022         long timeout;
1023         int ret;
1024
1025         fw_work = container_of(work, struct firmware_work, work);
1026         fw_priv = _request_firmware_prepare(&fw, fw_work->name, fw_work->device,
1027                         fw_work->uevent, true);
1028         if (IS_ERR_OR_NULL(fw_priv)) {
1029                 ret = PTR_RET(fw_priv);
1030                 goto out;
1031         }
1032
1033         timeout = usermodehelper_read_lock_wait(firmware_loading_timeout());
1034         if (timeout) {
1035                 ret = _request_firmware_load(fw_priv, fw_work->uevent, timeout);
1036                 usermodehelper_read_unlock();
1037         } else {
1038                 dev_dbg(fw_work->device, "firmware: %s loading timed out\n",
1039                         fw_work->name);
1040                 ret = -EAGAIN;
1041         }
1042         if (ret)
1043                 _request_firmware_cleanup(&fw);
1044
1045  out:
1046         fw_work->cont(fw, fw_work->context);
1047         put_device(fw_work->device);
1048
1049         module_put(fw_work->module);
1050         kfree(fw_work);
1051 }
1052
1053 /**
1054  * request_firmware_nowait - asynchronous version of request_firmware
1055  * @module: module requesting the firmware
1056  * @uevent: sends uevent to copy the firmware image if this flag
1057  *      is non-zero else the firmware copy must be done manually.
1058  * @name: name of firmware file
1059  * @device: device for which firmware is being loaded
1060  * @gfp: allocation flags
1061  * @context: will be passed over to @cont, and
1062  *      @fw may be %NULL if firmware request fails.
1063  * @cont: function will be called asynchronously when the firmware
1064  *      request is over.
1065  *
1066  *      Caller must hold the reference count of @device.
1067  *
1068  *      Asynchronous variant of request_firmware() for user contexts:
1069  *              - sleep for as small periods as possible since it may
1070  *              increase kernel boot time of built-in device drivers
1071  *              requesting firmware in their ->probe() methods, if
1072  *              @gfp is GFP_KERNEL.
1073  *
1074  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1075  **/
1076 int
1077 request_firmware_nowait(
1078         struct module *module, bool uevent,
1079         const char *name, struct device *device, gfp_t gfp, void *context,
1080         void (*cont)(const struct firmware *fw, void *context))
1081 {
1082         struct firmware_work *fw_work;
1083
1084         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1085         if (!fw_work)
1086                 return -ENOMEM;
1087
1088         fw_work->module = module;
1089         fw_work->name = name;
1090         fw_work->device = device;
1091         fw_work->context = context;
1092         fw_work->cont = cont;
1093         fw_work->uevent = uevent;
1094
1095         if (!try_module_get(module)) {
1096                 kfree(fw_work);
1097                 return -EFAULT;
1098         }
1099
1100         get_device(fw_work->device);
1101         INIT_WORK(&fw_work->work, request_firmware_work_func);
1102         schedule_work(&fw_work->work);
1103         return 0;
1104 }
1105
1106 /**
1107  * cache_firmware - cache one firmware image in kernel memory space
1108  * @fw_name: the firmware image name
1109  *
1110  * Cache firmware in kernel memory so that drivers can use it when
1111  * system isn't ready for them to request firmware image from userspace.
1112  * Once it returns successfully, driver can use request_firmware or its
1113  * nowait version to get the cached firmware without any interacting
1114  * with userspace
1115  *
1116  * Return 0 if the firmware image has been cached successfully
1117  * Return !0 otherwise
1118  *
1119  */
1120 int cache_firmware(const char *fw_name)
1121 {
1122         int ret;
1123         const struct firmware *fw;
1124
1125         pr_debug("%s: %s\n", __func__, fw_name);
1126
1127         ret = request_firmware(&fw, fw_name, NULL);
1128         if (!ret)
1129                 kfree(fw);
1130
1131         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1132
1133         return ret;
1134 }
1135
1136 /**
1137  * uncache_firmware - remove one cached firmware image
1138  * @fw_name: the firmware image name
1139  *
1140  * Uncache one firmware image which has been cached successfully
1141  * before.
1142  *
1143  * Return 0 if the firmware cache has been removed successfully
1144  * Return !0 otherwise
1145  *
1146  */
1147 int uncache_firmware(const char *fw_name)
1148 {
1149         struct firmware_buf *buf;
1150         struct firmware fw;
1151
1152         pr_debug("%s: %s\n", __func__, fw_name);
1153
1154         if (fw_get_builtin_firmware(&fw, fw_name))
1155                 return 0;
1156
1157         buf = fw_lookup_buf(fw_name);
1158         if (buf) {
1159                 fw_free_buf(buf);
1160                 return 0;
1161         }
1162
1163         return -EINVAL;
1164 }
1165
1166 #ifdef CONFIG_PM_SLEEP
1167 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1168
1169 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1170 {
1171         struct fw_cache_entry *fce;
1172
1173         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1174         if (!fce)
1175                 goto exit;
1176
1177         strcpy(fce->name, name);
1178 exit:
1179         return fce;
1180 }
1181
1182 static int __fw_entry_found(const char *name)
1183 {
1184         struct firmware_cache *fwc = &fw_cache;
1185         struct fw_cache_entry *fce;
1186
1187         list_for_each_entry(fce, &fwc->fw_names, list) {
1188                 if (!strcmp(fce->name, name))
1189                         return 1;
1190         }
1191         return 0;
1192 }
1193
1194 static int fw_cache_piggyback_on_request(const char *name)
1195 {
1196         struct firmware_cache *fwc = &fw_cache;
1197         struct fw_cache_entry *fce;
1198         int ret = 0;
1199
1200         spin_lock(&fwc->name_lock);
1201         if (__fw_entry_found(name))
1202                 goto found;
1203
1204         fce = alloc_fw_cache_entry(name);
1205         if (fce) {
1206                 ret = 1;
1207                 list_add(&fce->list, &fwc->fw_names);
1208                 pr_debug("%s: fw: %s\n", __func__, name);
1209         }
1210 found:
1211         spin_unlock(&fwc->name_lock);
1212         return ret;
1213 }
1214
1215 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1216 {
1217         kfree(fce);
1218 }
1219
1220 static void __async_dev_cache_fw_image(void *fw_entry,
1221                                        async_cookie_t cookie)
1222 {
1223         struct fw_cache_entry *fce = fw_entry;
1224         struct firmware_cache *fwc = &fw_cache;
1225         int ret;
1226
1227         ret = cache_firmware(fce->name);
1228         if (ret) {
1229                 spin_lock(&fwc->name_lock);
1230                 list_del(&fce->list);
1231                 spin_unlock(&fwc->name_lock);
1232
1233                 free_fw_cache_entry(fce);
1234         }
1235 }
1236
1237 /* called with dev->devres_lock held */
1238 static void dev_create_fw_entry(struct device *dev, void *res,
1239                                 void *data)
1240 {
1241         struct fw_name_devm *fwn = res;
1242         const char *fw_name = fwn->name;
1243         struct list_head *head = data;
1244         struct fw_cache_entry *fce;
1245
1246         fce = alloc_fw_cache_entry(fw_name);
1247         if (fce)
1248                 list_add(&fce->list, head);
1249 }
1250
1251 static int devm_name_match(struct device *dev, void *res,
1252                            void *match_data)
1253 {
1254         struct fw_name_devm *fwn = res;
1255         return (fwn->magic == (unsigned long)match_data);
1256 }
1257
1258 static void dev_cache_fw_image(struct device *dev, void *data)
1259 {
1260         LIST_HEAD(todo);
1261         struct fw_cache_entry *fce;
1262         struct fw_cache_entry *fce_next;
1263         struct firmware_cache *fwc = &fw_cache;
1264
1265         devres_for_each_res(dev, fw_name_devm_release,
1266                             devm_name_match, &fw_cache,
1267                             dev_create_fw_entry, &todo);
1268
1269         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1270                 list_del(&fce->list);
1271
1272                 spin_lock(&fwc->name_lock);
1273                 /* only one cache entry for one firmware */
1274                 if (!__fw_entry_found(fce->name)) {
1275                         list_add(&fce->list, &fwc->fw_names);
1276                 } else {
1277                         free_fw_cache_entry(fce);
1278                         fce = NULL;
1279                 }
1280                 spin_unlock(&fwc->name_lock);
1281
1282                 if (fce)
1283                         async_schedule_domain(__async_dev_cache_fw_image,
1284                                               (void *)fce,
1285                                               &fw_cache_domain);
1286         }
1287 }
1288
1289 static void __device_uncache_fw_images(void)
1290 {
1291         struct firmware_cache *fwc = &fw_cache;
1292         struct fw_cache_entry *fce;
1293
1294         spin_lock(&fwc->name_lock);
1295         while (!list_empty(&fwc->fw_names)) {
1296                 fce = list_entry(fwc->fw_names.next,
1297                                 struct fw_cache_entry, list);
1298                 list_del(&fce->list);
1299                 spin_unlock(&fwc->name_lock);
1300
1301                 uncache_firmware(fce->name);
1302                 free_fw_cache_entry(fce);
1303
1304                 spin_lock(&fwc->name_lock);
1305         }
1306         spin_unlock(&fwc->name_lock);
1307 }
1308
1309 /**
1310  * device_cache_fw_images - cache devices' firmware
1311  *
1312  * If one device called request_firmware or its nowait version
1313  * successfully before, the firmware names are recored into the
1314  * device's devres link list, so device_cache_fw_images can call
1315  * cache_firmware() to cache these firmwares for the device,
1316  * then the device driver can load its firmwares easily at
1317  * time when system is not ready to complete loading firmware.
1318  */
1319 static void device_cache_fw_images(void)
1320 {
1321         struct firmware_cache *fwc = &fw_cache;
1322         int old_timeout;
1323         DEFINE_WAIT(wait);
1324
1325         pr_debug("%s\n", __func__);
1326
1327         /* cancel uncache work */
1328         cancel_delayed_work_sync(&fwc->work);
1329
1330         /*
1331          * use small loading timeout for caching devices' firmware
1332          * because all these firmware images have been loaded
1333          * successfully at lease once, also system is ready for
1334          * completing firmware loading now. The maximum size of
1335          * firmware in current distributions is about 2M bytes,
1336          * so 10 secs should be enough.
1337          */
1338         old_timeout = loading_timeout;
1339         loading_timeout = 10;
1340
1341         mutex_lock(&fw_lock);
1342         fwc->state = FW_LOADER_START_CACHE;
1343         dpm_for_each_dev(NULL, dev_cache_fw_image);
1344         mutex_unlock(&fw_lock);
1345
1346         /* wait for completion of caching firmware for all devices */
1347         async_synchronize_full_domain(&fw_cache_domain);
1348
1349         loading_timeout = old_timeout;
1350 }
1351
1352 /**
1353  * device_uncache_fw_images - uncache devices' firmware
1354  *
1355  * uncache all firmwares which have been cached successfully
1356  * by device_uncache_fw_images earlier
1357  */
1358 static void device_uncache_fw_images(void)
1359 {
1360         pr_debug("%s\n", __func__);
1361         __device_uncache_fw_images();
1362 }
1363
1364 static void device_uncache_fw_images_work(struct work_struct *work)
1365 {
1366         device_uncache_fw_images();
1367 }
1368
1369 /**
1370  * device_uncache_fw_images_delay - uncache devices firmwares
1371  * @delay: number of milliseconds to delay uncache device firmwares
1372  *
1373  * uncache all devices's firmwares which has been cached successfully
1374  * by device_cache_fw_images after @delay milliseconds.
1375  */
1376 static void device_uncache_fw_images_delay(unsigned long delay)
1377 {
1378         schedule_delayed_work(&fw_cache.work,
1379                         msecs_to_jiffies(delay));
1380 }
1381
1382 static int fw_pm_notify(struct notifier_block *notify_block,
1383                         unsigned long mode, void *unused)
1384 {
1385         switch (mode) {
1386         case PM_HIBERNATION_PREPARE:
1387         case PM_SUSPEND_PREPARE:
1388                 device_cache_fw_images();
1389                 break;
1390
1391         case PM_POST_SUSPEND:
1392         case PM_POST_HIBERNATION:
1393         case PM_POST_RESTORE:
1394                 /*
1395                  * In case that system sleep failed and syscore_suspend is
1396                  * not called.
1397                  */
1398                 mutex_lock(&fw_lock);
1399                 fw_cache.state = FW_LOADER_NO_CACHE;
1400                 mutex_unlock(&fw_lock);
1401
1402                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1403                 break;
1404         }
1405
1406         return 0;
1407 }
1408
1409 /* stop caching firmware once syscore_suspend is reached */
1410 static int fw_suspend(void)
1411 {
1412         fw_cache.state = FW_LOADER_NO_CACHE;
1413         return 0;
1414 }
1415
1416 static struct syscore_ops fw_syscore_ops = {
1417         .suspend = fw_suspend,
1418 };
1419 #else
1420 static int fw_cache_piggyback_on_request(const char *name)
1421 {
1422         return 0;
1423 }
1424 #endif
1425
1426 static void __init fw_cache_init(void)
1427 {
1428         spin_lock_init(&fw_cache.lock);
1429         INIT_LIST_HEAD(&fw_cache.head);
1430         fw_cache.state = FW_LOADER_NO_CACHE;
1431
1432 #ifdef CONFIG_PM_SLEEP
1433         spin_lock_init(&fw_cache.name_lock);
1434         INIT_LIST_HEAD(&fw_cache.fw_names);
1435
1436         INIT_DELAYED_WORK(&fw_cache.work,
1437                           device_uncache_fw_images_work);
1438
1439         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1440         register_pm_notifier(&fw_cache.pm_notify);
1441
1442         register_syscore_ops(&fw_syscore_ops);
1443 #endif
1444 }
1445
1446 static int __init firmware_class_init(void)
1447 {
1448         fw_cache_init();
1449         return class_register(&firmware_class);
1450 }
1451
1452 static void __exit firmware_class_exit(void)
1453 {
1454 #ifdef CONFIG_PM_SLEEP
1455         unregister_syscore_ops(&fw_syscore_ops);
1456         unregister_pm_notifier(&fw_cache.pm_notify);
1457 #endif
1458         class_unregister(&firmware_class);
1459 }
1460
1461 fs_initcall(firmware_class_init);
1462 module_exit(firmware_class_exit);
1463
1464 EXPORT_SYMBOL(release_firmware);
1465 EXPORT_SYMBOL(request_firmware);
1466 EXPORT_SYMBOL(request_firmware_nowait);
1467 EXPORT_SYMBOL_GPL(cache_firmware);
1468 EXPORT_SYMBOL_GPL(uncache_firmware);