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 #include <linux/reboot.h>
  31
  32 #include <generated/utsrelease.h>
  33
  34 #include "base.h"
  35
  36 MODULE_AUTHOR("Manuel Estrada Sainz");
  37 MODULE_DESCRIPTION("Multi purpose firmware loading support");
  38 MODULE_LICENSE("GPL");
  39
  40 /* Builtin firmware support */
  41
  42 #ifdef CONFIG_FW_LOADER
  43
  44 extern struct builtin_fw __start_builtin_fw[];
  45 extern struct builtin_fw __end_builtin_fw[];
  46
  47 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  48 {
  49         struct builtin_fw *b_fw;
  50
  51         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
  52                 if (strcmp(name, b_fw->name) == 0) {
  53                         fw->size = b_fw->size;
  54                         fw->data = b_fw->data;
  55                         return true;
  56                 }
  57         }
  58
  59         return false;
  60 }
  61
  62 static bool fw_is_builtin_firmware(const struct firmware *fw)
  63 {
  64         struct builtin_fw *b_fw;
  65
  66         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
  67                 if (fw->data == b_fw->data)
  68                         return true;
  69
  70         return false;
  71 }
  72
  73 #else /* Module case - no builtin firmware support */
  74
  75 static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  76 {
  77         return false;
  78 }
  79
  80 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
  81 {
  82         return false;
  83 }
  84 #endif
  85
  86 enum {
  87         FW_STATUS_LOADING,
  88         FW_STATUS_DONE,
  89         FW_STATUS_ABORT,
  90 };
  91
  92 static int loading_timeout = 60;        /* In seconds */
  93
  94 static inline long firmware_loading_timeout(void)
  95 {
  96         return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
  97 }
  98
  99 struct firmware_cache {
 100         /* firmware_buf instance will be added into the below list */
 101         spinlock_t lock;
 102         struct list_head head;
 103         int state;
 104
 105 #ifdef CONFIG_PM_SLEEP
 106         /*
 107          * Names of firmware images which have been cached successfully
 108          * will be added into the below list so that device uncache
 109          * helper can trace which firmware images have been cached
 110          * before.
 111          */
 112         spinlock_t name_lock;
 113         struct list_head fw_names;
 114
 115         struct delayed_work work;
 116
 117         struct notifier_block   pm_notify;
 118 #endif
 119 };
 120
 121 struct firmware_buf {
 122         struct kref ref;
 123         struct list_head list;
 124         struct completion completion;
 125         struct firmware_cache *fwc;
 126         unsigned long status;
 127         void *data;
 128         size_t size;
 129 #ifdef CONFIG_FW_LOADER_USER_HELPER
 130         bool is_paged_buf;
 131         struct page **pages;
 132         int nr_pages;
 133         int page_array_size;
 134         struct list_head pending_list;
 135 #endif
 136         char fw_id[];
 137 };
 138
 139 struct fw_cache_entry {
 140         struct list_head list;
 141         char name[];
 142 };
 143
 144 struct fw_name_devm {
 145         unsigned long magic;
 146         char name[];
 147 };
 148
 149 #define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
 150
 151 #define FW_LOADER_NO_CACHE      0
 152 #define FW_LOADER_START_CACHE   1
 153
 154 static int fw_cache_piggyback_on_request(const char *name);
 155
 156 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
 157  * guarding for corner cases a global lock should be OK */
 158 static DEFINE_MUTEX(fw_lock);
 159
 160 static struct firmware_cache fw_cache;
 161
 162 static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
 163                                               struct firmware_cache *fwc)
 164 {
 165         struct firmware_buf *buf;
 166
 167         buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1 , GFP_ATOMIC);
 168
 169         if (!buf)
 170                 return buf;
 171
 172         kref_init(&buf->ref);
 173         strcpy(buf->fw_id, fw_name);
 174         buf->fwc = fwc;
 175         init_completion(&buf->completion);
 176 #ifdef CONFIG_FW_LOADER_USER_HELPER
 177         INIT_LIST_HEAD(&buf->pending_list);
 178 #endif
 179
 180         pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
 181
 182         return buf;
 183 }
 184
 185 static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
 186 {
 187         struct firmware_buf *tmp;
 188         struct firmware_cache *fwc = &fw_cache;
 189
 190         list_for_each_entry(tmp, &fwc->head, list)
 191                 if (!strcmp(tmp->fw_id, fw_name))
 192                         return tmp;
 193         return NULL;
 194 }
 195
 196 static int fw_lookup_and_allocate_buf(const char *fw_name,
 197                                       struct firmware_cache *fwc,
 198                                       struct firmware_buf **buf)
 199 {
 200         struct firmware_buf *tmp;
 201
 202         spin_lock(&fwc->lock);
 203         tmp = __fw_lookup_buf(fw_name);
 204         if (tmp) {
 205                 kref_get(&tmp->ref);
 206                 spin_unlock(&fwc->lock);
 207                 *buf = tmp;
 208                 return 1;
 209         }
 210         tmp = __allocate_fw_buf(fw_name, fwc);
 211         if (tmp)
 212                 list_add(&tmp->list, &fwc->head);
 213         spin_unlock(&fwc->lock);
 214
 215         *buf = tmp;
 216
 217         return tmp ? 0 : -ENOMEM;
 218 }
 219
 220 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
 221 {
 222         struct firmware_buf *tmp;
 223         struct firmware_cache *fwc = &fw_cache;
 224
 225         spin_lock(&fwc->lock);
 226         tmp = __fw_lookup_buf(fw_name);
 227         spin_unlock(&fwc->lock);
 228
 229         return tmp;
 230 }
 231
 232 static void __fw_free_buf(struct kref *ref)
 233 {
 234         struct firmware_buf *buf = to_fwbuf(ref);
 235         struct firmware_cache *fwc = buf->fwc;
 236
 237         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 238                  __func__, buf->fw_id, buf, buf->data,
 239                  (unsigned int)buf->size);
 240
 241         list_del(&buf->list);
 242         spin_unlock(&fwc->lock);
 243
 244 #ifdef CONFIG_FW_LOADER_USER_HELPER
 245         if (buf->is_paged_buf) {
 246                 int i;
 247                 vunmap(buf->data);
 248                 for (i = 0; i < buf->nr_pages; i++)
 249                         __free_page(buf->pages[i]);
 250                 kfree(buf->pages);
 251         } else
 252 #endif
 253                 vfree(buf->data);
 254         kfree(buf);
 255 }
 256
 257 static void fw_free_buf(struct firmware_buf *buf)
 258 {
 259         struct firmware_cache *fwc = buf->fwc;
 260         spin_lock(&fwc->lock);
 261         if (!kref_put(&buf->ref, __fw_free_buf))
 262                 spin_unlock(&fwc->lock);
 263 }
 264
 265 /* direct firmware loading support */
 266 static char fw_path_para[256];
 267 static const char * const fw_path[] = {
 268         fw_path_para,
 269         "/lib/firmware/updates/" UTS_RELEASE,
 270         "/lib/firmware/updates",
 271         "/lib/firmware/" UTS_RELEASE,
 272         "/lib/firmware"
 273 };
 274
 275 /*
 276  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 277  * from kernel command line because firmware_class is generally built in
 278  * kernel instead of module.
 279  */
 280 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 281 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 282
 283 /* Don't inline this: 'struct kstat' is biggish */
 284 static noinline_for_stack long fw_file_size(struct file *file)
 285 {
 286         struct kstat st;
 287         if (vfs_getattr(&file->f_path, &st))
 288                 return -1;
 289         if (!S_ISREG(st.mode))
 290                 return -1;
 291         if (st.size != (long)st.size)
 292                 return -1;
 293         return st.size;
 294 }
 295
 296 static bool fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
 297 {
 298         long size;
 299         char *buf;
 300
 301         size = fw_file_size(file);
 302         if (size <= 0)
 303                 return false;
 304         buf = vmalloc(size);
 305         if (!buf)
 306                 return false;
 307         if (kernel_read(file, 0, buf, size) != size) {
 308                 vfree(buf);
 309                 return false;
 310         }
 311         fw_buf->data = buf;
 312         fw_buf->size = size;
 313         return true;
 314 }
 315
 316 static bool fw_get_filesystem_firmware(struct device *device,
 317                                        struct firmware_buf *buf)
 318 {
 319         int i;
 320         bool success = false;
 321         char *path = __getname();
 322
 323         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 324                 struct file *file;
 325
 326                 /* skip the unset customized path */
 327                 if (!fw_path[i][0])
 328                         continue;
 329
 330                 snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
 331
 332                 file = filp_open(path, O_RDONLY, 0);
 333                 if (IS_ERR(file))
 334                         continue;
 335                 success = fw_read_file_contents(file, buf);
 336                 fput(file);
 337                 if (success)
 338                         break;
 339         }
 340         __putname(path);
 341
 342         if (success) {
 343                 dev_dbg(device, "firmware: direct-loading firmware %s\n",
 344                         buf->fw_id);
 345                 mutex_lock(&fw_lock);
 346                 set_bit(FW_STATUS_DONE, &buf->status);
 347                 complete_all(&buf->completion);
 348                 mutex_unlock(&fw_lock);
 349         }
 350
 351         return success;
 352 }
 353
 354 /* firmware holds the ownership of pages */
 355 static void firmware_free_data(const struct firmware *fw)
 356 {
 357         /* Loaded directly? */
 358         if (!fw->priv) {
 359                 vfree(fw->data);
 360                 return;
 361         }
 362         fw_free_buf(fw->priv);
 363 }
 364
 365 /* store the pages buffer info firmware from buf */
 366 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
 367 {
 368         fw->priv = buf;
 369 #ifdef CONFIG_FW_LOADER_USER_HELPER
 370         fw->pages = buf->pages;
 371 #endif
 372         fw->size = buf->size;
 373         fw->data = buf->data;
 374
 375         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 376                  __func__, buf->fw_id, buf, buf->data,
 377                  (unsigned int)buf->size);
 378 }
 379
 380 #ifdef CONFIG_PM_SLEEP
 381 static void fw_name_devm_release(struct device *dev, void *res)
 382 {
 383         struct fw_name_devm *fwn = res;
 384
 385         if (fwn->magic == (unsigned long)&fw_cache)
 386                 pr_debug("%s: fw_name-%s devm-%p released\n",
 387                                 __func__, fwn->name, res);
 388 }
 389
 390 static int fw_devm_match(struct device *dev, void *res,
 391                 void *match_data)
 392 {
 393         struct fw_name_devm *fwn = res;
 394
 395         return (fwn->magic == (unsigned long)&fw_cache) &&
 396                 !strcmp(fwn->name, match_data);
 397 }
 398
 399 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 400                 const char *name)
 401 {
 402         struct fw_name_devm *fwn;
 403
 404         fwn = devres_find(dev, fw_name_devm_release,
 405                           fw_devm_match, (void *)name);
 406         return fwn;
 407 }
 408
 409 /* add firmware name into devres list */
 410 static int fw_add_devm_name(struct device *dev, const char *name)
 411 {
 412         struct fw_name_devm *fwn;
 413
 414         fwn = fw_find_devm_name(dev, name);
 415         if (fwn)
 416                 return 1;
 417
 418         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
 419                            strlen(name) + 1, GFP_KERNEL);
 420         if (!fwn)
 421                 return -ENOMEM;
 422
 423         fwn->magic = (unsigned long)&fw_cache;
 424         strcpy(fwn->name, name);
 425         devres_add(dev, fwn);
 426
 427         return 0;
 428 }
 429 #else
 430 static int fw_add_devm_name(struct device *dev, const char *name)
 431 {
 432         return 0;
 433 }
 434 #endif
 435
 436
 437 /*
 438  * user-mode helper code
 439  */
 440 #ifdef CONFIG_FW_LOADER_USER_HELPER
 441 struct firmware_priv {
 442         struct delayed_work timeout_work;
 443         bool nowait;
 444         struct device dev;
 445         struct firmware_buf *buf;
 446         struct firmware *fw;
 447 };
 448
 449 static struct firmware_priv *to_firmware_priv(struct device *dev)
 450 {
 451         return container_of(dev, struct firmware_priv, dev);
 452 }
 453
 454 static void __fw_load_abort(struct firmware_buf *buf)
 455 {
 456         /*
 457          * There is a small window in which user can write to 'loading'
 458          * between loading done and disappearance of 'loading'
 459          */
 460         if (test_bit(FW_STATUS_DONE, &buf->status))
 461                 return;
 462
 463         list_del_init(&buf->pending_list);
 464         set_bit(FW_STATUS_ABORT, &buf->status);
 465         complete_all(&buf->completion);
 466 }
 467
 468 static void fw_load_abort(struct firmware_priv *fw_priv)
 469 {
 470         struct firmware_buf *buf = fw_priv->buf;
 471
 472         __fw_load_abort(buf);
 473
 474         /* avoid user action after loading abort */
 475         fw_priv->buf = NULL;
 476 }
 477
 478 #define is_fw_load_aborted(buf) \
 479         test_bit(FW_STATUS_ABORT, &(buf)->status)
 480
 481 static LIST_HEAD(pending_fw_head);
 482
 483 /* reboot notifier for avoid deadlock with usermode_lock */
 484 static int fw_shutdown_notify(struct notifier_block *unused1,
 485                               unsigned long unused2, void *unused3)
 486 {
 487         mutex_lock(&fw_lock);
 488         while (!list_empty(&pending_fw_head))
 489                 __fw_load_abort(list_first_entry(&pending_fw_head,
 490                                                struct firmware_buf,
 491                                                pending_list));
 492         mutex_unlock(&fw_lock);
 493         return NOTIFY_DONE;
 494 }
 495
 496 static struct notifier_block fw_shutdown_nb = {
 497         .notifier_call = fw_shutdown_notify,
 498 };
 499
 500 static ssize_t firmware_timeout_show(struct class *class,
 501                                      struct class_attribute *attr,
 502                                      char *buf)
 503 {
 504         return sprintf(buf, "%d\n", loading_timeout);
 505 }
 506
 507 /**
 508  * firmware_timeout_store - set number of seconds to wait for firmware
 509  * @class: device class pointer
 510  * @attr: device attribute pointer
 511  * @buf: buffer to scan for timeout value
 512  * @count: number of bytes in @buf
 513  *
 514  *      Sets the number of seconds to wait for the firmware.  Once
 515  *      this expires an error will be returned to the driver and no
 516  *      firmware will be provided.
 517  *
 518  *      Note: zero means 'wait forever'.
 519  **/
 520 static ssize_t firmware_timeout_store(struct class *class,
 521                                       struct class_attribute *attr,
 522                                       const char *buf, size_t count)
 523 {
 524         loading_timeout = simple_strtol(buf, NULL, 10);
 525         if (loading_timeout < 0)
 526                 loading_timeout = 0;
 527
 528         return count;
 529 }
 530
 531 static struct class_attribute firmware_class_attrs[] = {
 532         __ATTR(timeout, S_IWUSR | S_IRUGO,
 533                 firmware_timeout_show, firmware_timeout_store),
 534         __ATTR_NULL
 535 };
 536
 537 static void fw_dev_release(struct device *dev)
 538 {
 539         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 540
 541         kfree(fw_priv);
 542
 543         module_put(THIS_MODULE);
 544 }
 545
 546 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 547 {
 548         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 549
 550         if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
 551                 return -ENOMEM;
 552         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
 553                 return -ENOMEM;
 554         if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
 555                 return -ENOMEM;
 556
 557         return 0;
 558 }
 559
 560 static struct class firmware_class = {
 561         .name           = "firmware",
 562         .class_attrs    = firmware_class_attrs,
 563         .dev_uevent     = firmware_uevent,
 564         .dev_release    = fw_dev_release,
 565 };
 566
 567 static ssize_t firmware_loading_show(struct device *dev,
 568                                      struct device_attribute *attr, char *buf)
 569 {
 570         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 571         int loading = 0;
 572
 573         mutex_lock(&fw_lock);
 574         if (fw_priv->buf)
 575                 loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
 576         mutex_unlock(&fw_lock);
 577
 578         return sprintf(buf, "%d\n", loading);
 579 }
 580
 581 /* Some architectures don't have PAGE_KERNEL_RO */
 582 #ifndef PAGE_KERNEL_RO
 583 #define PAGE_KERNEL_RO PAGE_KERNEL
 584 #endif
 585
 586 /* one pages buffer should be mapped/unmapped only once */
 587 static int fw_map_pages_buf(struct firmware_buf *buf)
 588 {
 589         if (!buf->is_paged_buf)
 590                 return 0;
 591
 592         if (buf->data)
 593                 vunmap(buf->data);
 594         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 595         if (!buf->data)
 596                 return -ENOMEM;
 597         return 0;
 598 }
 599
 600 /**
 601  * firmware_loading_store - set value in the 'loading' control file
 602  * @dev: device pointer
 603  * @attr: device attribute pointer
 604  * @buf: buffer to scan for loading control value
 605  * @count: number of bytes in @buf
 606  *
 607  *      The relevant values are:
 608  *
 609  *       1: Start a load, discarding any previous partial load.
 610  *       0: Conclude the load and hand the data to the driver code.
 611  *      -1: Conclude the load with an error and discard any written data.
 612  **/
 613 static ssize_t firmware_loading_store(struct device *dev,
 614                                       struct device_attribute *attr,
 615                                       const char *buf, size_t count)
 616 {
 617         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 618         struct firmware_buf *fw_buf;
 619         int loading = simple_strtol(buf, NULL, 10);
 620         int i;
 621
 622         mutex_lock(&fw_lock);
 623         fw_buf = fw_priv->buf;
 624         if (!fw_buf)
 625                 goto out;
 626
 627         switch (loading) {
 628         case 1:
 629                 /* discarding any previous partial load */
 630                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
 631                         for (i = 0; i < fw_buf->nr_pages; i++)
 632                                 __free_page(fw_buf->pages[i]);
 633                         kfree(fw_buf->pages);
 634                         fw_buf->pages = NULL;
 635                         fw_buf->page_array_size = 0;
 636                         fw_buf->nr_pages = 0;
 637                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
 638                 }
 639                 break;
 640         case 0:
 641                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
 642                         set_bit(FW_STATUS_DONE, &fw_buf->status);
 643                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
 644
 645                         /*
 646                          * Several loading requests may be pending on
 647                          * one same firmware buf, so let all requests
 648                          * see the mapped 'buf->data' once the loading
 649                          * is completed.
 650                          * */
 651                         fw_map_pages_buf(fw_buf);
 652                         list_del_init(&fw_buf->pending_list);
 653                         complete_all(&fw_buf->completion);
 654                         break;
 655                 }
 656                 /* fallthrough */
 657         default:
 658                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 659                 /* fallthrough */
 660         case -1:
 661                 fw_load_abort(fw_priv);
 662                 break;
 663         }
 664 out:
 665         mutex_unlock(&fw_lock);
 666         return count;
 667 }
 668
 669 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 670
 671 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 672                                   struct bin_attribute *bin_attr,
 673                                   char *buffer, loff_t offset, size_t count)
 674 {
 675         struct device *dev = kobj_to_dev(kobj);
 676         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 677         struct firmware_buf *buf;
 678         ssize_t ret_count;
 679
 680         mutex_lock(&fw_lock);
 681         buf = fw_priv->buf;
 682         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 683                 ret_count = -ENODEV;
 684                 goto out;
 685         }
 686         if (offset > buf->size) {
 687                 ret_count = 0;
 688                 goto out;
 689         }
 690         if (count > buf->size - offset)
 691                 count = buf->size - offset;
 692
 693         ret_count = count;
 694
 695         while (count) {
 696                 void *page_data;
 697                 int page_nr = offset >> PAGE_SHIFT;
 698                 int page_ofs = offset & (PAGE_SIZE-1);
 699                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 700
 701                 page_data = kmap(buf->pages[page_nr]);
 702
 703                 memcpy(buffer, page_data + page_ofs, page_cnt);
 704
 705                 kunmap(buf->pages[page_nr]);
 706                 buffer += page_cnt;
 707                 offset += page_cnt;
 708                 count -= page_cnt;
 709         }
 710 out:
 711         mutex_unlock(&fw_lock);
 712         return ret_count;
 713 }
 714
 715 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 716 {
 717         struct firmware_buf *buf = fw_priv->buf;
 718         int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
 719
 720         /* If the array of pages is too small, grow it... */
 721         if (buf->page_array_size < pages_needed) {
 722                 int new_array_size = max(pages_needed,
 723                                          buf->page_array_size * 2);
 724                 struct page **new_pages;
 725
 726                 new_pages = kmalloc(new_array_size * sizeof(void *),
 727                                     GFP_KERNEL);
 728                 if (!new_pages) {
 729                         fw_load_abort(fw_priv);
 730                         return -ENOMEM;
 731                 }
 732                 memcpy(new_pages, buf->pages,
 733                        buf->page_array_size * sizeof(void *));
 734                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 735                        (new_array_size - buf->page_array_size));
 736                 kfree(buf->pages);
 737                 buf->pages = new_pages;
 738                 buf->page_array_size = new_array_size;
 739         }
 740
 741         while (buf->nr_pages < pages_needed) {
 742                 buf->pages[buf->nr_pages] =
 743                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 744
 745                 if (!buf->pages[buf->nr_pages]) {
 746                         fw_load_abort(fw_priv);
 747                         return -ENOMEM;
 748                 }
 749                 buf->nr_pages++;
 750         }
 751         return 0;
 752 }
 753
 754 /**
 755  * firmware_data_write - write method for firmware
 756  * @filp: open sysfs file
 757  * @kobj: kobject for the device
 758  * @bin_attr: bin_attr structure
 759  * @buffer: buffer being written
 760  * @offset: buffer offset for write in total data store area
 761  * @count: buffer size
 762  *
 763  *      Data written to the 'data' attribute will be later handed to
 764  *      the driver as a firmware image.
 765  **/
 766 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 767                                    struct bin_attribute *bin_attr,
 768                                    char *buffer, loff_t offset, size_t count)
 769 {
 770         struct device *dev = kobj_to_dev(kobj);
 771         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 772         struct firmware_buf *buf;
 773         ssize_t retval;
 774
 775         if (!capable(CAP_SYS_RAWIO))
 776                 return -EPERM;
 777
 778         mutex_lock(&fw_lock);
 779         buf = fw_priv->buf;
 780         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 781                 retval = -ENODEV;
 782                 goto out;
 783         }
 784
 785         retval = fw_realloc_buffer(fw_priv, offset + count);
 786         if (retval)
 787                 goto out;
 788
 789         retval = count;
 790
 791         while (count) {
 792                 void *page_data;
 793                 int page_nr = offset >> PAGE_SHIFT;
 794                 int page_ofs = offset & (PAGE_SIZE - 1);
 795                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 796
 797                 page_data = kmap(buf->pages[page_nr]);
 798
 799                 memcpy(page_data + page_ofs, buffer, page_cnt);
 800
 801                 kunmap(buf->pages[page_nr]);
 802                 buffer += page_cnt;
 803                 offset += page_cnt;
 804                 count -= page_cnt;
 805         }
 806
 807         buf->size = max_t(size_t, offset, buf->size);
 808 out:
 809         mutex_unlock(&fw_lock);
 810         return retval;
 811 }
 812
 813 static struct bin_attribute firmware_attr_data = {
 814         .attr = { .name = "data", .mode = 0644 },
 815         .size = 0,
 816         .read = firmware_data_read,
 817         .write = firmware_data_write,
 818 };
 819
 820 static void firmware_class_timeout_work(struct work_struct *work)
 821 {
 822         struct firmware_priv *fw_priv = container_of(work,
 823                         struct firmware_priv, timeout_work.work);
 824
 825         mutex_lock(&fw_lock);
 826         fw_load_abort(fw_priv);
 827         mutex_unlock(&fw_lock);
 828 }
 829
 830 static struct firmware_priv *
 831 fw_create_instance(struct firmware *firmware, const char *fw_name,
 832                    struct device *device, bool uevent, bool nowait)
 833 {
 834         struct firmware_priv *fw_priv;
 835         struct device *f_dev;
 836
 837         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 838         if (!fw_priv) {
 839                 dev_err(device, "%s: kmalloc failed\n", __func__);
 840                 fw_priv = ERR_PTR(-ENOMEM);
 841                 goto exit;
 842         }
 843
 844         fw_priv->nowait = nowait;
 845         fw_priv->fw = firmware;
 846         INIT_DELAYED_WORK(&fw_priv->timeout_work,
 847                 firmware_class_timeout_work);
 848
 849         f_dev = &fw_priv->dev;
 850
 851         device_initialize(f_dev);
 852         dev_set_name(f_dev, "%s", fw_name);
 853         f_dev->parent = device;
 854         f_dev->class = &firmware_class;
 855 exit:
 856         return fw_priv;
 857 }
 858
 859 /* load a firmware via user helper */
 860 static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
 861                                   long timeout)
 862 {
 863         int retval = 0;
 864         struct device *f_dev = &fw_priv->dev;
 865         struct firmware_buf *buf = fw_priv->buf;
 866
 867         /* fall back on userspace loading */
 868         buf->is_paged_buf = true;
 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         mutex_lock(&fw_lock);
 888         list_add(&buf->pending_list, &pending_fw_head);
 889         mutex_unlock(&fw_lock);
 890
 891         retval = device_create_file(f_dev, &dev_attr_loading);
 892         if (retval) {
 893                 mutex_lock(&fw_lock);
 894                 list_del_init(&buf->pending_list);
 895                 mutex_unlock(&fw_lock);
 896                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
 897                 goto err_del_bin_attr;
 898         }
 899
 900         if (uevent) {
 901                 dev_set_uevent_suppress(f_dev, false);
 902                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
 903                 if (timeout != MAX_SCHEDULE_TIMEOUT)
 904                         schedule_delayed_work(&fw_priv->timeout_work, timeout);
 905
 906                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 907         }
 908
 909         wait_for_completion(&buf->completion);
 910
 911         cancel_delayed_work_sync(&fw_priv->timeout_work);
 912
 913         device_remove_file(f_dev, &dev_attr_loading);
 914 err_del_bin_attr:
 915         device_remove_bin_file(f_dev, &firmware_attr_data);
 916 err_del_dev:
 917         device_del(f_dev);
 918 err_put_dev:
 919         put_device(f_dev);
 920         return retval;
 921 }
 922
 923 static int fw_load_from_user_helper(struct firmware *firmware,
 924                                     const char *name, struct device *device,
 925                                     bool uevent, bool nowait, long timeout)
 926 {
 927         struct firmware_priv *fw_priv;
 928
 929         fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
 930         if (IS_ERR(fw_priv))
 931                 return PTR_ERR(fw_priv);
 932
 933         fw_priv->buf = firmware->priv;
 934         return _request_firmware_load(fw_priv, uevent, timeout);
 935 }
 936 #else /* CONFIG_FW_LOADER_USER_HELPER */
 937 static inline int
 938 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 939                          struct device *device, bool uevent, bool nowait,
 940                          long timeout)
 941 {
 942         return -ENOENT;
 943 }
 944
 945 /* No abort during direct loading */
 946 #define is_fw_load_aborted(buf) false
 947
 948 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 949
 950
 951 /* wait until the shared firmware_buf becomes ready (or error) */
 952 static int sync_cached_firmware_buf(struct firmware_buf *buf)
 953 {
 954         int ret = 0;
 955
 956         mutex_lock(&fw_lock);
 957         while (!test_bit(FW_STATUS_DONE, &buf->status)) {
 958                 if (is_fw_load_aborted(buf)) {
 959                         ret = -ENOENT;
 960                         break;
 961                 }
 962                 mutex_unlock(&fw_lock);
 963                 wait_for_completion(&buf->completion);
 964                 mutex_lock(&fw_lock);
 965         }
 966         mutex_unlock(&fw_lock);
 967         return ret;
 968 }
 969
 970 /* prepare firmware and firmware_buf structs;
 971  * return 0 if a firmware is already assigned, 1 if need to load one,
 972  * or a negative error code
 973  */
 974 static int
 975 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
 976                           struct device *device)
 977 {
 978         struct firmware *firmware;
 979         struct firmware_buf *buf;
 980         int ret;
 981
 982         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
 983         if (!firmware) {
 984                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
 985                         __func__);
 986                 return -ENOMEM;
 987         }
 988
 989         if (fw_get_builtin_firmware(firmware, name)) {
 990                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
 991                 return 0; /* assigned */
 992         }
 993
 994         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
 995
 996         /*
 997          * bind with 'buf' now to avoid warning in failure path
 998          * of requesting firmware.
 999          */
1000         firmware->priv = buf;
1001
1002         if (ret > 0) {
1003                 ret = sync_cached_firmware_buf(buf);
1004                 if (!ret) {
1005                         fw_set_page_data(buf, firmware);
1006                         return 0; /* assigned */
1007                 }
1008         }
1009
1010         if (ret < 0)
1011                 return ret;
1012         return 1; /* need to load */
1013 }
1014
1015 static int assign_firmware_buf(struct firmware *fw, struct device *device)
1016 {
1017         struct firmware_buf *buf = fw->priv;
1018
1019         mutex_lock(&fw_lock);
1020         if (!buf->size || is_fw_load_aborted(buf)) {
1021                 mutex_unlock(&fw_lock);
1022                 return -ENOENT;
1023         }
1024
1025         /*
1026          * add firmware name into devres list so that we can auto cache
1027          * and uncache firmware for device.
1028          *
1029          * device may has been deleted already, but the problem
1030          * should be fixed in devres or driver core.
1031          */
1032         if (device)
1033                 fw_add_devm_name(device, buf->fw_id);
1034
1035         /*
1036          * After caching firmware image is started, let it piggyback
1037          * on request firmware.
1038          */
1039         if (buf->fwc->state == FW_LOADER_START_CACHE) {
1040                 if (fw_cache_piggyback_on_request(buf->fw_id))
1041                         kref_get(&buf->ref);
1042         }
1043
1044         /* pass the pages buffer to driver at the last minute */
1045         fw_set_page_data(buf, fw);
1046         mutex_unlock(&fw_lock);
1047         return 0;
1048 }
1049
1050 /* called from request_firmware() and request_firmware_work_func() */
1051 static int
1052 _request_firmware(const struct firmware **firmware_p, const char *name,
1053                   struct device *device, bool uevent, bool nowait)
1054 {
1055         struct firmware *fw;
1056         long timeout;
1057         int ret;
1058
1059         if (!firmware_p)
1060                 return -EINVAL;
1061
1062         ret = _request_firmware_prepare(&fw, name, device);
1063         if (ret <= 0) /* error or already assigned */
1064                 goto out;
1065
1066         ret = 0;
1067         timeout = firmware_loading_timeout();
1068         if (nowait) {
1069                 timeout = usermodehelper_read_lock_wait(timeout);
1070                 if (!timeout) {
1071                         dev_dbg(device, "firmware: %s loading timed out\n",
1072                                 name);
1073                         ret = -EBUSY;
1074                         goto out;
1075                 }
1076         } else {
1077                 ret = usermodehelper_read_trylock();
1078                 if (WARN_ON(ret)) {
1079                         dev_err(device, "firmware: %s will not be loaded\n",
1080                                 name);
1081                         goto out;
1082                 }
1083         }
1084
1085         if (!fw_get_filesystem_firmware(device, fw->priv))
1086                 ret = fw_load_from_user_helper(fw, name, device,
1087                                                uevent, nowait, timeout);
1088         if (!ret)
1089                 ret = assign_firmware_buf(fw, device);
1090
1091         usermodehelper_read_unlock();
1092
1093  out:
1094         if (ret < 0) {
1095                 release_firmware(fw);
1096                 fw = NULL;
1097         }
1098
1099         *firmware_p = fw;
1100         return ret;
1101 }
1102
1103 /**
1104  * request_firmware: - send firmware request and wait for it
1105  * @firmware_p: pointer to firmware image
1106  * @name: name of firmware file
1107  * @device: device for which firmware is being loaded
1108  *
1109  *      @firmware_p will be used to return a firmware image by the name
1110  *      of @name for device @device.
1111  *
1112  *      Should be called from user context where sleeping is allowed.
1113  *
1114  *      @name will be used as $FIRMWARE in the uevent environment and
1115  *      should be distinctive enough not to be confused with any other
1116  *      firmware image for this or any other device.
1117  *
1118  *      Caller must hold the reference count of @device.
1119  *
1120  *      The function can be called safely inside device's suspend and
1121  *      resume callback.
1122  **/
1123 int
1124 request_firmware(const struct firmware **firmware_p, const char *name,
1125                  struct device *device)
1126 {
1127         return _request_firmware(firmware_p, name, device, true, false);
1128 }
1129
1130 /**
1131  * release_firmware: - release the resource associated with a firmware image
1132  * @fw: firmware resource to release
1133  **/
1134 void release_firmware(const struct firmware *fw)
1135 {
1136         if (fw) {
1137                 if (!fw_is_builtin_firmware(fw))
1138                         firmware_free_data(fw);
1139                 kfree(fw);
1140         }
1141 }
1142
1143 /* Async support */
1144 struct firmware_work {
1145         struct work_struct work;
1146         struct module *module;
1147         const char *name;
1148         struct device *device;
1149         void *context;
1150         void (*cont)(const struct firmware *fw, void *context);
1151         bool uevent;
1152 };
1153
1154 static void request_firmware_work_func(struct work_struct *work)
1155 {
1156         struct firmware_work *fw_work;
1157         const struct firmware *fw;
1158
1159         fw_work = container_of(work, struct firmware_work, work);
1160
1161         _request_firmware(&fw, fw_work->name, fw_work->device,
1162                           fw_work->uevent, true);
1163         fw_work->cont(fw, fw_work->context);
1164         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1165
1166         module_put(fw_work->module);
1167         kfree(fw_work);
1168 }
1169
1170 /**
1171  * request_firmware_nowait - asynchronous version of request_firmware
1172  * @module: module requesting the firmware
1173  * @uevent: sends uevent to copy the firmware image if this flag
1174  *      is non-zero else the firmware copy must be done manually.
1175  * @name: name of firmware file
1176  * @device: device for which firmware is being loaded
1177  * @gfp: allocation flags
1178  * @context: will be passed over to @cont, and
1179  *      @fw may be %NULL if firmware request fails.
1180  * @cont: function will be called asynchronously when the firmware
1181  *      request is over.
1182  *
1183  *      Caller must hold the reference count of @device.
1184  *
1185  *      Asynchronous variant of request_firmware() for user contexts:
1186  *              - sleep for as small periods as possible since it may
1187  *              increase kernel boot time of built-in device drivers
1188  *              requesting firmware in their ->probe() methods, if
1189  *              @gfp is GFP_KERNEL.
1190  *
1191  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1192  **/
1193 int
1194 request_firmware_nowait(
1195         struct module *module, bool uevent,
1196         const char *name, struct device *device, gfp_t gfp, void *context,
1197         void (*cont)(const struct firmware *fw, void *context))
1198 {
1199         struct firmware_work *fw_work;
1200
1201         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1202         if (!fw_work)
1203                 return -ENOMEM;
1204
1205         fw_work->module = module;
1206         fw_work->name = name;
1207         fw_work->device = device;
1208         fw_work->context = context;
1209         fw_work->cont = cont;
1210         fw_work->uevent = uevent;
1211
1212         if (!try_module_get(module)) {
1213                 kfree(fw_work);
1214                 return -EFAULT;
1215         }
1216
1217         get_device(fw_work->device);
1218         INIT_WORK(&fw_work->work, request_firmware_work_func);
1219         schedule_work(&fw_work->work);
1220         return 0;
1221 }
1222
1223 /**
1224  * cache_firmware - cache one firmware image in kernel memory space
1225  * @fw_name: the firmware image name
1226  *
1227  * Cache firmware in kernel memory so that drivers can use it when
1228  * system isn't ready for them to request firmware image from userspace.
1229  * Once it returns successfully, driver can use request_firmware or its
1230  * nowait version to get the cached firmware without any interacting
1231  * with userspace
1232  *
1233  * Return 0 if the firmware image has been cached successfully
1234  * Return !0 otherwise
1235  *
1236  */
1237 int cache_firmware(const char *fw_name)
1238 {
1239         int ret;
1240         const struct firmware *fw;
1241
1242         pr_debug("%s: %s\n", __func__, fw_name);
1243
1244         ret = request_firmware(&fw, fw_name, NULL);
1245         if (!ret)
1246                 kfree(fw);
1247
1248         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1249
1250         return ret;
1251 }
1252
1253 /**
1254  * uncache_firmware - remove one cached firmware image
1255  * @fw_name: the firmware image name
1256  *
1257  * Uncache one firmware image which has been cached successfully
1258  * before.
1259  *
1260  * Return 0 if the firmware cache has been removed successfully
1261  * Return !0 otherwise
1262  *
1263  */
1264 int uncache_firmware(const char *fw_name)
1265 {
1266         struct firmware_buf *buf;
1267         struct firmware fw;
1268
1269         pr_debug("%s: %s\n", __func__, fw_name);
1270
1271         if (fw_get_builtin_firmware(&fw, fw_name))
1272                 return 0;
1273
1274         buf = fw_lookup_buf(fw_name);
1275         if (buf) {
1276                 fw_free_buf(buf);
1277                 return 0;
1278         }
1279
1280         return -EINVAL;
1281 }
1282
1283 #ifdef CONFIG_PM_SLEEP
1284 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1285
1286 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1287 {
1288         struct fw_cache_entry *fce;
1289
1290         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1291         if (!fce)
1292                 goto exit;
1293
1294         strcpy(fce->name, name);
1295 exit:
1296         return fce;
1297 }
1298
1299 static int __fw_entry_found(const char *name)
1300 {
1301         struct firmware_cache *fwc = &fw_cache;
1302         struct fw_cache_entry *fce;
1303
1304         list_for_each_entry(fce, &fwc->fw_names, list) {
1305                 if (!strcmp(fce->name, name))
1306                         return 1;
1307         }
1308         return 0;
1309 }
1310
1311 static int fw_cache_piggyback_on_request(const char *name)
1312 {
1313         struct firmware_cache *fwc = &fw_cache;
1314         struct fw_cache_entry *fce;
1315         int ret = 0;
1316
1317         spin_lock(&fwc->name_lock);
1318         if (__fw_entry_found(name))
1319                 goto found;
1320
1321         fce = alloc_fw_cache_entry(name);
1322         if (fce) {
1323                 ret = 1;
1324                 list_add(&fce->list, &fwc->fw_names);
1325                 pr_debug("%s: fw: %s\n", __func__, name);
1326         }
1327 found:
1328         spin_unlock(&fwc->name_lock);
1329         return ret;
1330 }
1331
1332 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1333 {
1334         kfree(fce);
1335 }
1336
1337 static void __async_dev_cache_fw_image(void *fw_entry,
1338                                        async_cookie_t cookie)
1339 {
1340         struct fw_cache_entry *fce = fw_entry;
1341         struct firmware_cache *fwc = &fw_cache;
1342         int ret;
1343
1344         ret = cache_firmware(fce->name);
1345         if (ret) {
1346                 spin_lock(&fwc->name_lock);
1347                 list_del(&fce->list);
1348                 spin_unlock(&fwc->name_lock);
1349
1350                 free_fw_cache_entry(fce);
1351         }
1352 }
1353
1354 /* called with dev->devres_lock held */
1355 static void dev_create_fw_entry(struct device *dev, void *res,
1356                                 void *data)
1357 {
1358         struct fw_name_devm *fwn = res;
1359         const char *fw_name = fwn->name;
1360         struct list_head *head = data;
1361         struct fw_cache_entry *fce;
1362
1363         fce = alloc_fw_cache_entry(fw_name);
1364         if (fce)
1365                 list_add(&fce->list, head);
1366 }
1367
1368 static int devm_name_match(struct device *dev, void *res,
1369                            void *match_data)
1370 {
1371         struct fw_name_devm *fwn = res;
1372         return (fwn->magic == (unsigned long)match_data);
1373 }
1374
1375 static void dev_cache_fw_image(struct device *dev, void *data)
1376 {
1377         LIST_HEAD(todo);
1378         struct fw_cache_entry *fce;
1379         struct fw_cache_entry *fce_next;
1380         struct firmware_cache *fwc = &fw_cache;
1381
1382         devres_for_each_res(dev, fw_name_devm_release,
1383                             devm_name_match, &fw_cache,
1384                             dev_create_fw_entry, &todo);
1385
1386         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1387                 list_del(&fce->list);
1388
1389                 spin_lock(&fwc->name_lock);
1390                 /* only one cache entry for one firmware */
1391                 if (!__fw_entry_found(fce->name)) {
1392                         list_add(&fce->list, &fwc->fw_names);
1393                 } else {
1394                         free_fw_cache_entry(fce);
1395                         fce = NULL;
1396                 }
1397                 spin_unlock(&fwc->name_lock);
1398
1399                 if (fce)
1400                         async_schedule_domain(__async_dev_cache_fw_image,
1401                                               (void *)fce,
1402                                               &fw_cache_domain);
1403         }
1404 }
1405
1406 static void __device_uncache_fw_images(void)
1407 {
1408         struct firmware_cache *fwc = &fw_cache;
1409         struct fw_cache_entry *fce;
1410
1411         spin_lock(&fwc->name_lock);
1412         while (!list_empty(&fwc->fw_names)) {
1413                 fce = list_entry(fwc->fw_names.next,
1414                                 struct fw_cache_entry, list);
1415                 list_del(&fce->list);
1416                 spin_unlock(&fwc->name_lock);
1417
1418                 uncache_firmware(fce->name);
1419                 free_fw_cache_entry(fce);
1420
1421                 spin_lock(&fwc->name_lock);
1422         }
1423         spin_unlock(&fwc->name_lock);
1424 }
1425
1426 /**
1427  * device_cache_fw_images - cache devices' firmware
1428  *
1429  * If one device called request_firmware or its nowait version
1430  * successfully before, the firmware names are recored into the
1431  * device's devres link list, so device_cache_fw_images can call
1432  * cache_firmware() to cache these firmwares for the device,
1433  * then the device driver can load its firmwares easily at
1434  * time when system is not ready to complete loading firmware.
1435  */
1436 static void device_cache_fw_images(void)
1437 {
1438         struct firmware_cache *fwc = &fw_cache;
1439         int old_timeout;
1440         DEFINE_WAIT(wait);
1441
1442         pr_debug("%s\n", __func__);
1443
1444         /* cancel uncache work */
1445         cancel_delayed_work_sync(&fwc->work);
1446
1447         /*
1448          * use small loading timeout for caching devices' firmware
1449          * because all these firmware images have been loaded
1450          * successfully at lease once, also system is ready for
1451          * completing firmware loading now. The maximum size of
1452          * firmware in current distributions is about 2M bytes,
1453          * so 10 secs should be enough.
1454          */
1455         old_timeout = loading_timeout;
1456         loading_timeout = 10;
1457
1458         mutex_lock(&fw_lock);
1459         fwc->state = FW_LOADER_START_CACHE;
1460         dpm_for_each_dev(NULL, dev_cache_fw_image);
1461         mutex_unlock(&fw_lock);
1462
1463         /* wait for completion of caching firmware for all devices */
1464         async_synchronize_full_domain(&fw_cache_domain);
1465
1466         loading_timeout = old_timeout;
1467 }
1468
1469 /**
1470  * device_uncache_fw_images - uncache devices' firmware
1471  *
1472  * uncache all firmwares which have been cached successfully
1473  * by device_uncache_fw_images earlier
1474  */
1475 static void device_uncache_fw_images(void)
1476 {
1477         pr_debug("%s\n", __func__);
1478         __device_uncache_fw_images();
1479 }
1480
1481 static void device_uncache_fw_images_work(struct work_struct *work)
1482 {
1483         device_uncache_fw_images();
1484 }
1485
1486 /**
1487  * device_uncache_fw_images_delay - uncache devices firmwares
1488  * @delay: number of milliseconds to delay uncache device firmwares
1489  *
1490  * uncache all devices's firmwares which has been cached successfully
1491  * by device_cache_fw_images after @delay milliseconds.
1492  */
1493 static void device_uncache_fw_images_delay(unsigned long delay)
1494 {
1495         schedule_delayed_work(&fw_cache.work,
1496                         msecs_to_jiffies(delay));
1497 }
1498
1499 static int fw_pm_notify(struct notifier_block *notify_block,
1500                         unsigned long mode, void *unused)
1501 {
1502         switch (mode) {
1503         case PM_HIBERNATION_PREPARE:
1504         case PM_SUSPEND_PREPARE:
1505                 device_cache_fw_images();
1506                 break;
1507
1508         case PM_POST_SUSPEND:
1509         case PM_POST_HIBERNATION:
1510         case PM_POST_RESTORE:
1511                 /*
1512                  * In case that system sleep failed and syscore_suspend is
1513                  * not called.
1514                  */
1515                 mutex_lock(&fw_lock);
1516                 fw_cache.state = FW_LOADER_NO_CACHE;
1517                 mutex_unlock(&fw_lock);
1518
1519                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1520                 break;
1521         }
1522
1523         return 0;
1524 }
1525
1526 /* stop caching firmware once syscore_suspend is reached */
1527 static int fw_suspend(void)
1528 {
1529         fw_cache.state = FW_LOADER_NO_CACHE;
1530         return 0;
1531 }
1532
1533 static struct syscore_ops fw_syscore_ops = {
1534         .suspend = fw_suspend,
1535 };
1536 #else
1537 static int fw_cache_piggyback_on_request(const char *name)
1538 {
1539         return 0;
1540 }
1541 #endif
1542
1543 static void __init fw_cache_init(void)
1544 {
1545         spin_lock_init(&fw_cache.lock);
1546         INIT_LIST_HEAD(&fw_cache.head);
1547         fw_cache.state = FW_LOADER_NO_CACHE;
1548
1549 #ifdef CONFIG_PM_SLEEP
1550         spin_lock_init(&fw_cache.name_lock);
1551         INIT_LIST_HEAD(&fw_cache.fw_names);
1552
1553         INIT_DELAYED_WORK(&fw_cache.work,
1554                           device_uncache_fw_images_work);
1555
1556         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1557         register_pm_notifier(&fw_cache.pm_notify);
1558
1559         register_syscore_ops(&fw_syscore_ops);
1560 #endif
1561 }
1562
1563 static int __init firmware_class_init(void)
1564 {
1565         fw_cache_init();
1566 #ifdef CONFIG_FW_LOADER_USER_HELPER
1567         register_reboot_notifier(&fw_shutdown_nb);
1568         return class_register(&firmware_class);
1569 #else
1570         return 0;
1571 #endif
1572 }
1573
1574 static void __exit firmware_class_exit(void)
1575 {
1576 #ifdef CONFIG_PM_SLEEP
1577         unregister_syscore_ops(&fw_syscore_ops);
1578         unregister_pm_notifier(&fw_cache.pm_notify);
1579 #endif
1580 #ifdef CONFIG_FW_LOADER_USER_HELPER
1581         unregister_reboot_notifier(&fw_shutdown_nb);
1582         class_unregister(&firmware_class);
1583 #endif
1584 }
1585
1586 fs_initcall(firmware_class_init);
1587 module_exit(firmware_class_exit);
1588
1589 EXPORT_SYMBOL(release_firmware);
1590 EXPORT_SYMBOL(request_firmware);
1591 EXPORT_SYMBOL(request_firmware_nowait);
1592 EXPORT_SYMBOL_GPL(cache_firmware);
1593 EXPORT_SYMBOL_GPL(uncache_firmware);