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         bool need_uevent;
 132         struct page **pages;
 133         int nr_pages;
 134         int page_array_size;
 135         struct list_head pending_list;
 136 #endif
 137         char fw_id[];
 138 };
 139
 140 struct fw_cache_entry {
 141         struct list_head list;
 142         char name[];
 143 };
 144
 145 struct fw_name_devm {
 146         unsigned long magic;
 147         char name[];
 148 };
 149
 150 #define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
 151
 152 #define FW_LOADER_NO_CACHE      0
 153 #define FW_LOADER_START_CACHE   1
 154
 155 static int fw_cache_piggyback_on_request(const char *name);
 156
 157 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
 158  * guarding for corner cases a global lock should be OK */
 159 static DEFINE_MUTEX(fw_lock);
 160
 161 static struct firmware_cache fw_cache;
 162
 163 static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
 164                                               struct firmware_cache *fwc)
 165 {
 166         struct firmware_buf *buf;
 167
 168         buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1 , GFP_ATOMIC);
 169
 170         if (!buf)
 171                 return buf;
 172
 173         kref_init(&buf->ref);
 174         strcpy(buf->fw_id, fw_name);
 175         buf->fwc = fwc;
 176         init_completion(&buf->completion);
 177 #ifdef CONFIG_FW_LOADER_USER_HELPER
 178         INIT_LIST_HEAD(&buf->pending_list);
 179 #endif
 180
 181         pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
 182
 183         return buf;
 184 }
 185
 186 static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
 187 {
 188         struct firmware_buf *tmp;
 189         struct firmware_cache *fwc = &fw_cache;
 190
 191         list_for_each_entry(tmp, &fwc->head, list)
 192                 if (!strcmp(tmp->fw_id, fw_name))
 193                         return tmp;
 194         return NULL;
 195 }
 196
 197 static int fw_lookup_and_allocate_buf(const char *fw_name,
 198                                       struct firmware_cache *fwc,
 199                                       struct firmware_buf **buf)
 200 {
 201         struct firmware_buf *tmp;
 202
 203         spin_lock(&fwc->lock);
 204         tmp = __fw_lookup_buf(fw_name);
 205         if (tmp) {
 206                 kref_get(&tmp->ref);
 207                 spin_unlock(&fwc->lock);
 208                 *buf = tmp;
 209                 return 1;
 210         }
 211         tmp = __allocate_fw_buf(fw_name, fwc);
 212         if (tmp)
 213                 list_add(&tmp->list, &fwc->head);
 214         spin_unlock(&fwc->lock);
 215
 216         *buf = tmp;
 217
 218         return tmp ? 0 : -ENOMEM;
 219 }
 220
 221 static void __fw_free_buf(struct kref *ref)
 222 {
 223         struct firmware_buf *buf = to_fwbuf(ref);
 224         struct firmware_cache *fwc = buf->fwc;
 225
 226         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 227                  __func__, buf->fw_id, buf, buf->data,
 228                  (unsigned int)buf->size);
 229
 230         list_del(&buf->list);
 231         spin_unlock(&fwc->lock);
 232
 233 #ifdef CONFIG_FW_LOADER_USER_HELPER
 234         if (buf->is_paged_buf) {
 235                 int i;
 236                 vunmap(buf->data);
 237                 for (i = 0; i < buf->nr_pages; i++)
 238                         __free_page(buf->pages[i]);
 239                 kfree(buf->pages);
 240         } else
 241 #endif
 242                 vfree(buf->data);
 243         kfree(buf);
 244 }
 245
 246 static void fw_free_buf(struct firmware_buf *buf)
 247 {
 248         struct firmware_cache *fwc = buf->fwc;
 249         spin_lock(&fwc->lock);
 250         if (!kref_put(&buf->ref, __fw_free_buf))
 251                 spin_unlock(&fwc->lock);
 252 }
 253
 254 /* direct firmware loading support */
 255 static char fw_path_para[256];
 256 static const char * const fw_path[] = {
 257         fw_path_para,
 258         "/lib/firmware/updates/" UTS_RELEASE,
 259         "/lib/firmware/updates",
 260         "/lib/firmware/" UTS_RELEASE,
 261         "/lib/firmware"
 262 };
 263
 264 /*
 265  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 266  * from kernel command line because firmware_class is generally built in
 267  * kernel instead of module.
 268  */
 269 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 270 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 271
 272 /* Don't inline this: 'struct kstat' is biggish */
 273 static noinline_for_stack long fw_file_size(struct file *file)
 274 {
 275         struct kstat st;
 276         if (vfs_getattr(&file->f_path, &st))
 277                 return -1;
 278         if (!S_ISREG(st.mode))
 279                 return -1;
 280         if (st.size != (long)st.size)
 281                 return -1;
 282         return st.size;
 283 }
 284
 285 static bool fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
 286 {
 287         long size;
 288         char *buf;
 289
 290         size = fw_file_size(file);
 291         if (size <= 0)
 292                 return false;
 293         buf = vmalloc(size);
 294         if (!buf)
 295                 return false;
 296         if (kernel_read(file, 0, buf, size) != size) {
 297                 vfree(buf);
 298                 return false;
 299         }
 300         fw_buf->data = buf;
 301         fw_buf->size = size;
 302         return true;
 303 }
 304
 305 static bool fw_get_filesystem_firmware(struct device *device,
 306                                        struct firmware_buf *buf)
 307 {
 308         int i;
 309         bool success = false;
 310         char *path = __getname();
 311
 312         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 313                 struct file *file;
 314
 315                 /* skip the unset customized path */
 316                 if (!fw_path[i][0])
 317                         continue;
 318
 319                 snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
 320
 321                 file = filp_open(path, O_RDONLY, 0);
 322                 if (IS_ERR(file))
 323                         continue;
 324                 success = fw_read_file_contents(file, buf);
 325                 fput(file);
 326                 if (success)
 327                         break;
 328         }
 329         __putname(path);
 330
 331         if (success) {
 332                 dev_dbg(device, "firmware: direct-loading firmware %s\n",
 333                         buf->fw_id);
 334                 mutex_lock(&fw_lock);
 335                 set_bit(FW_STATUS_DONE, &buf->status);
 336                 complete_all(&buf->completion);
 337                 mutex_unlock(&fw_lock);
 338         }
 339
 340         return success;
 341 }
 342
 343 /* firmware holds the ownership of pages */
 344 static void firmware_free_data(const struct firmware *fw)
 345 {
 346         /* Loaded directly? */
 347         if (!fw->priv) {
 348                 vfree(fw->data);
 349                 return;
 350         }
 351         fw_free_buf(fw->priv);
 352 }
 353
 354 /* store the pages buffer info firmware from buf */
 355 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
 356 {
 357         fw->priv = buf;
 358 #ifdef CONFIG_FW_LOADER_USER_HELPER
 359         fw->pages = buf->pages;
 360 #endif
 361         fw->size = buf->size;
 362         fw->data = buf->data;
 363
 364         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 365                  __func__, buf->fw_id, buf, buf->data,
 366                  (unsigned int)buf->size);
 367 }
 368
 369 #ifdef CONFIG_PM_SLEEP
 370 static void fw_name_devm_release(struct device *dev, void *res)
 371 {
 372         struct fw_name_devm *fwn = res;
 373
 374         if (fwn->magic == (unsigned long)&fw_cache)
 375                 pr_debug("%s: fw_name-%s devm-%p released\n",
 376                                 __func__, fwn->name, res);
 377 }
 378
 379 static int fw_devm_match(struct device *dev, void *res,
 380                 void *match_data)
 381 {
 382         struct fw_name_devm *fwn = res;
 383
 384         return (fwn->magic == (unsigned long)&fw_cache) &&
 385                 !strcmp(fwn->name, match_data);
 386 }
 387
 388 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 389                 const char *name)
 390 {
 391         struct fw_name_devm *fwn;
 392
 393         fwn = devres_find(dev, fw_name_devm_release,
 394                           fw_devm_match, (void *)name);
 395         return fwn;
 396 }
 397
 398 /* add firmware name into devres list */
 399 static int fw_add_devm_name(struct device *dev, const char *name)
 400 {
 401         struct fw_name_devm *fwn;
 402
 403         fwn = fw_find_devm_name(dev, name);
 404         if (fwn)
 405                 return 1;
 406
 407         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
 408                            strlen(name) + 1, GFP_KERNEL);
 409         if (!fwn)
 410                 return -ENOMEM;
 411
 412         fwn->magic = (unsigned long)&fw_cache;
 413         strcpy(fwn->name, name);
 414         devres_add(dev, fwn);
 415
 416         return 0;
 417 }
 418 #else
 419 static int fw_add_devm_name(struct device *dev, const char *name)
 420 {
 421         return 0;
 422 }
 423 #endif
 424
 425
 426 /*
 427  * user-mode helper code
 428  */
 429 #ifdef CONFIG_FW_LOADER_USER_HELPER
 430 struct firmware_priv {
 431         struct delayed_work timeout_work;
 432         bool nowait;
 433         struct device dev;
 434         struct firmware_buf *buf;
 435         struct firmware *fw;
 436 };
 437
 438 static struct firmware_priv *to_firmware_priv(struct device *dev)
 439 {
 440         return container_of(dev, struct firmware_priv, dev);
 441 }
 442
 443 static void __fw_load_abort(struct firmware_buf *buf)
 444 {
 445         /*
 446          * There is a small window in which user can write to 'loading'
 447          * between loading done and disappearance of 'loading'
 448          */
 449         if (test_bit(FW_STATUS_DONE, &buf->status))
 450                 return;
 451
 452         list_del_init(&buf->pending_list);
 453         set_bit(FW_STATUS_ABORT, &buf->status);
 454         complete_all(&buf->completion);
 455 }
 456
 457 static void fw_load_abort(struct firmware_priv *fw_priv)
 458 {
 459         struct firmware_buf *buf = fw_priv->buf;
 460
 461         __fw_load_abort(buf);
 462
 463         /* avoid user action after loading abort */
 464         fw_priv->buf = NULL;
 465 }
 466
 467 #define is_fw_load_aborted(buf) \
 468         test_bit(FW_STATUS_ABORT, &(buf)->status)
 469
 470 static LIST_HEAD(pending_fw_head);
 471
 472 /* reboot notifier for avoid deadlock with usermode_lock */
 473 static int fw_shutdown_notify(struct notifier_block *unused1,
 474                               unsigned long unused2, void *unused3)
 475 {
 476         mutex_lock(&fw_lock);
 477         while (!list_empty(&pending_fw_head))
 478                 __fw_load_abort(list_first_entry(&pending_fw_head,
 479                                                struct firmware_buf,
 480                                                pending_list));
 481         mutex_unlock(&fw_lock);
 482         return NOTIFY_DONE;
 483 }
 484
 485 static struct notifier_block fw_shutdown_nb = {
 486         .notifier_call = fw_shutdown_notify,
 487 };
 488
 489 static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
 490                             char *buf)
 491 {
 492         return sprintf(buf, "%d\n", loading_timeout);
 493 }
 494
 495 /**
 496  * firmware_timeout_store - set number of seconds to wait for firmware
 497  * @class: device class pointer
 498  * @attr: device attribute pointer
 499  * @buf: buffer to scan for timeout value
 500  * @count: number of bytes in @buf
 501  *
 502  *      Sets the number of seconds to wait for the firmware.  Once
 503  *      this expires an error will be returned to the driver and no
 504  *      firmware will be provided.
 505  *
 506  *      Note: zero means 'wait forever'.
 507  **/
 508 static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
 509                              const char *buf, size_t count)
 510 {
 511         loading_timeout = simple_strtol(buf, NULL, 10);
 512         if (loading_timeout < 0)
 513                 loading_timeout = 0;
 514
 515         return count;
 516 }
 517
 518 static struct class_attribute firmware_class_attrs[] = {
 519         __ATTR_RW(timeout),
 520         __ATTR_NULL
 521 };
 522
 523 static void fw_dev_release(struct device *dev)
 524 {
 525         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 526
 527         kfree(fw_priv);
 528 }
 529
 530 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 531 {
 532         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 533
 534         if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
 535                 return -ENOMEM;
 536         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
 537                 return -ENOMEM;
 538         if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
 539                 return -ENOMEM;
 540
 541         return 0;
 542 }
 543
 544 static struct class firmware_class = {
 545         .name           = "firmware",
 546         .class_attrs    = firmware_class_attrs,
 547         .dev_uevent     = firmware_uevent,
 548         .dev_release    = fw_dev_release,
 549 };
 550
 551 static ssize_t firmware_loading_show(struct device *dev,
 552                                      struct device_attribute *attr, char *buf)
 553 {
 554         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 555         int loading = 0;
 556
 557         mutex_lock(&fw_lock);
 558         if (fw_priv->buf)
 559                 loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
 560         mutex_unlock(&fw_lock);
 561
 562         return sprintf(buf, "%d\n", loading);
 563 }
 564
 565 /* Some architectures don't have PAGE_KERNEL_RO */
 566 #ifndef PAGE_KERNEL_RO
 567 #define PAGE_KERNEL_RO PAGE_KERNEL
 568 #endif
 569
 570 /* one pages buffer should be mapped/unmapped only once */
 571 static int fw_map_pages_buf(struct firmware_buf *buf)
 572 {
 573         if (!buf->is_paged_buf)
 574                 return 0;
 575
 576         if (buf->data)
 577                 vunmap(buf->data);
 578         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 579         if (!buf->data)
 580                 return -ENOMEM;
 581         return 0;
 582 }
 583
 584 /**
 585  * firmware_loading_store - set value in the 'loading' control file
 586  * @dev: device pointer
 587  * @attr: device attribute pointer
 588  * @buf: buffer to scan for loading control value
 589  * @count: number of bytes in @buf
 590  *
 591  *      The relevant values are:
 592  *
 593  *       1: Start a load, discarding any previous partial load.
 594  *       0: Conclude the load and hand the data to the driver code.
 595  *      -1: Conclude the load with an error and discard any written data.
 596  **/
 597 static ssize_t firmware_loading_store(struct device *dev,
 598                                       struct device_attribute *attr,
 599                                       const char *buf, size_t count)
 600 {
 601         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 602         struct firmware_buf *fw_buf;
 603         int loading = simple_strtol(buf, NULL, 10);
 604         int i;
 605
 606         mutex_lock(&fw_lock);
 607         fw_buf = fw_priv->buf;
 608         if (!fw_buf)
 609                 goto out;
 610
 611         switch (loading) {
 612         case 1:
 613                 /* discarding any previous partial load */
 614                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
 615                         for (i = 0; i < fw_buf->nr_pages; i++)
 616                                 __free_page(fw_buf->pages[i]);
 617                         kfree(fw_buf->pages);
 618                         fw_buf->pages = NULL;
 619                         fw_buf->page_array_size = 0;
 620                         fw_buf->nr_pages = 0;
 621                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
 622                 }
 623                 break;
 624         case 0:
 625                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
 626                         set_bit(FW_STATUS_DONE, &fw_buf->status);
 627                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
 628
 629                         /*
 630                          * Several loading requests may be pending on
 631                          * one same firmware buf, so let all requests
 632                          * see the mapped 'buf->data' once the loading
 633                          * is completed.
 634                          * */
 635                         fw_map_pages_buf(fw_buf);
 636                         list_del_init(&fw_buf->pending_list);
 637                         complete_all(&fw_buf->completion);
 638                         break;
 639                 }
 640                 /* fallthrough */
 641         default:
 642                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 643                 /* fallthrough */
 644         case -1:
 645                 fw_load_abort(fw_priv);
 646                 break;
 647         }
 648 out:
 649         mutex_unlock(&fw_lock);
 650         return count;
 651 }
 652
 653 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 654
 655 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 656                                   struct bin_attribute *bin_attr,
 657                                   char *buffer, loff_t offset, size_t count)
 658 {
 659         struct device *dev = kobj_to_dev(kobj);
 660         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 661         struct firmware_buf *buf;
 662         ssize_t ret_count;
 663
 664         mutex_lock(&fw_lock);
 665         buf = fw_priv->buf;
 666         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 667                 ret_count = -ENODEV;
 668                 goto out;
 669         }
 670         if (offset > buf->size) {
 671                 ret_count = 0;
 672                 goto out;
 673         }
 674         if (count > buf->size - offset)
 675                 count = buf->size - offset;
 676
 677         ret_count = count;
 678
 679         while (count) {
 680                 void *page_data;
 681                 int page_nr = offset >> PAGE_SHIFT;
 682                 int page_ofs = offset & (PAGE_SIZE-1);
 683                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 684
 685                 page_data = kmap(buf->pages[page_nr]);
 686
 687                 memcpy(buffer, page_data + page_ofs, page_cnt);
 688
 689                 kunmap(buf->pages[page_nr]);
 690                 buffer += page_cnt;
 691                 offset += page_cnt;
 692                 count -= page_cnt;
 693         }
 694 out:
 695         mutex_unlock(&fw_lock);
 696         return ret_count;
 697 }
 698
 699 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 700 {
 701         struct firmware_buf *buf = fw_priv->buf;
 702         int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
 703
 704         /* If the array of pages is too small, grow it... */
 705         if (buf->page_array_size < pages_needed) {
 706                 int new_array_size = max(pages_needed,
 707                                          buf->page_array_size * 2);
 708                 struct page **new_pages;
 709
 710                 new_pages = kmalloc(new_array_size * sizeof(void *),
 711                                     GFP_KERNEL);
 712                 if (!new_pages) {
 713                         fw_load_abort(fw_priv);
 714                         return -ENOMEM;
 715                 }
 716                 memcpy(new_pages, buf->pages,
 717                        buf->page_array_size * sizeof(void *));
 718                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 719                        (new_array_size - buf->page_array_size));
 720                 kfree(buf->pages);
 721                 buf->pages = new_pages;
 722                 buf->page_array_size = new_array_size;
 723         }
 724
 725         while (buf->nr_pages < pages_needed) {
 726                 buf->pages[buf->nr_pages] =
 727                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 728
 729                 if (!buf->pages[buf->nr_pages]) {
 730                         fw_load_abort(fw_priv);
 731                         return -ENOMEM;
 732                 }
 733                 buf->nr_pages++;
 734         }
 735         return 0;
 736 }
 737
 738 /**
 739  * firmware_data_write - write method for firmware
 740  * @filp: open sysfs file
 741  * @kobj: kobject for the device
 742  * @bin_attr: bin_attr structure
 743  * @buffer: buffer being written
 744  * @offset: buffer offset for write in total data store area
 745  * @count: buffer size
 746  *
 747  *      Data written to the 'data' attribute will be later handed to
 748  *      the driver as a firmware image.
 749  **/
 750 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 751                                    struct bin_attribute *bin_attr,
 752                                    char *buffer, loff_t offset, size_t count)
 753 {
 754         struct device *dev = kobj_to_dev(kobj);
 755         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 756         struct firmware_buf *buf;
 757         ssize_t retval;
 758
 759         if (!capable(CAP_SYS_RAWIO))
 760                 return -EPERM;
 761
 762         mutex_lock(&fw_lock);
 763         buf = fw_priv->buf;
 764         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 765                 retval = -ENODEV;
 766                 goto out;
 767         }
 768
 769         retval = fw_realloc_buffer(fw_priv, offset + count);
 770         if (retval)
 771                 goto out;
 772
 773         retval = count;
 774
 775         while (count) {
 776                 void *page_data;
 777                 int page_nr = offset >> PAGE_SHIFT;
 778                 int page_ofs = offset & (PAGE_SIZE - 1);
 779                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 780
 781                 page_data = kmap(buf->pages[page_nr]);
 782
 783                 memcpy(page_data + page_ofs, buffer, page_cnt);
 784
 785                 kunmap(buf->pages[page_nr]);
 786                 buffer += page_cnt;
 787                 offset += page_cnt;
 788                 count -= page_cnt;
 789         }
 790
 791         buf->size = max_t(size_t, offset, buf->size);
 792 out:
 793         mutex_unlock(&fw_lock);
 794         return retval;
 795 }
 796
 797 static struct bin_attribute firmware_attr_data = {
 798         .attr = { .name = "data", .mode = 0644 },
 799         .size = 0,
 800         .read = firmware_data_read,
 801         .write = firmware_data_write,
 802 };
 803
 804 static void firmware_class_timeout_work(struct work_struct *work)
 805 {
 806         struct firmware_priv *fw_priv = container_of(work,
 807                         struct firmware_priv, timeout_work.work);
 808
 809         mutex_lock(&fw_lock);
 810         fw_load_abort(fw_priv);
 811         mutex_unlock(&fw_lock);
 812 }
 813
 814 static struct firmware_priv *
 815 fw_create_instance(struct firmware *firmware, const char *fw_name,
 816                    struct device *device, bool uevent, bool nowait)
 817 {
 818         struct firmware_priv *fw_priv;
 819         struct device *f_dev;
 820
 821         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 822         if (!fw_priv) {
 823                 dev_err(device, "%s: kmalloc failed\n", __func__);
 824                 fw_priv = ERR_PTR(-ENOMEM);
 825                 goto exit;
 826         }
 827
 828         fw_priv->nowait = nowait;
 829         fw_priv->fw = firmware;
 830         INIT_DELAYED_WORK(&fw_priv->timeout_work,
 831                 firmware_class_timeout_work);
 832
 833         f_dev = &fw_priv->dev;
 834
 835         device_initialize(f_dev);
 836         dev_set_name(f_dev, "%s", fw_name);
 837         f_dev->parent = device;
 838         f_dev->class = &firmware_class;
 839 exit:
 840         return fw_priv;
 841 }
 842
 843 /* load a firmware via user helper */
 844 static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
 845                                   long timeout)
 846 {
 847         int retval = 0;
 848         struct device *f_dev = &fw_priv->dev;
 849         struct firmware_buf *buf = fw_priv->buf;
 850
 851         /* fall back on userspace loading */
 852         buf->is_paged_buf = true;
 853
 854         dev_set_uevent_suppress(f_dev, true);
 855
 856         retval = device_add(f_dev);
 857         if (retval) {
 858                 dev_err(f_dev, "%s: device_register failed\n", __func__);
 859                 goto err_put_dev;
 860         }
 861
 862         retval = device_create_bin_file(f_dev, &firmware_attr_data);
 863         if (retval) {
 864                 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
 865                 goto err_del_dev;
 866         }
 867
 868         mutex_lock(&fw_lock);
 869         list_add(&buf->pending_list, &pending_fw_head);
 870         mutex_unlock(&fw_lock);
 871
 872         retval = device_create_file(f_dev, &dev_attr_loading);
 873         if (retval) {
 874                 mutex_lock(&fw_lock);
 875                 list_del_init(&buf->pending_list);
 876                 mutex_unlock(&fw_lock);
 877                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
 878                 goto err_del_bin_attr;
 879         }
 880
 881         if (uevent) {
 882                 buf->need_uevent = true;
 883                 dev_set_uevent_suppress(f_dev, false);
 884                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
 885                 if (timeout != MAX_SCHEDULE_TIMEOUT)
 886                         schedule_delayed_work(&fw_priv->timeout_work, timeout);
 887
 888                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 889         }
 890
 891         wait_for_completion(&buf->completion);
 892
 893         cancel_delayed_work_sync(&fw_priv->timeout_work);
 894
 895         device_remove_file(f_dev, &dev_attr_loading);
 896 err_del_bin_attr:
 897         device_remove_bin_file(f_dev, &firmware_attr_data);
 898 err_del_dev:
 899         device_del(f_dev);
 900 err_put_dev:
 901         put_device(f_dev);
 902         return retval;
 903 }
 904
 905 static int fw_load_from_user_helper(struct firmware *firmware,
 906                                     const char *name, struct device *device,
 907                                     bool uevent, bool nowait, long timeout)
 908 {
 909         struct firmware_priv *fw_priv;
 910
 911         fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
 912         if (IS_ERR(fw_priv))
 913                 return PTR_ERR(fw_priv);
 914
 915         fw_priv->buf = firmware->priv;
 916         return _request_firmware_load(fw_priv, uevent, timeout);
 917 }
 918
 919 #ifdef CONFIG_PM_SLEEP
 920 /* kill pending requests without uevent to avoid blocking suspend */
 921 static void kill_requests_without_uevent(void)
 922 {
 923         struct firmware_buf *buf;
 924         struct firmware_buf *next;
 925
 926         mutex_lock(&fw_lock);
 927         list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
 928                 if (!buf->need_uevent)
 929                          __fw_load_abort(buf);
 930         }
 931         mutex_unlock(&fw_lock);
 932 }
 933 #endif
 934
 935 #else /* CONFIG_FW_LOADER_USER_HELPER */
 936 static inline int
 937 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 938                          struct device *device, bool uevent, bool nowait,
 939                          long timeout)
 940 {
 941         return -ENOENT;
 942 }
 943
 944 /* No abort during direct loading */
 945 #define is_fw_load_aborted(buf) false
 946
 947 #ifdef CONFIG_PM_SLEEP
 948 static inline void kill_requests_without_uevent(void) { }
 949 #endif
 950
 951 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 952
 953
 954 /* wait until the shared firmware_buf becomes ready (or error) */
 955 static int sync_cached_firmware_buf(struct firmware_buf *buf)
 956 {
 957         int ret = 0;
 958
 959         mutex_lock(&fw_lock);
 960         while (!test_bit(FW_STATUS_DONE, &buf->status)) {
 961                 if (is_fw_load_aborted(buf)) {
 962                         ret = -ENOENT;
 963                         break;
 964                 }
 965                 mutex_unlock(&fw_lock);
 966                 wait_for_completion(&buf->completion);
 967                 mutex_lock(&fw_lock);
 968         }
 969         mutex_unlock(&fw_lock);
 970         return ret;
 971 }
 972
 973 /* prepare firmware and firmware_buf structs;
 974  * return 0 if a firmware is already assigned, 1 if need to load one,
 975  * or a negative error code
 976  */
 977 static int
 978 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
 979                           struct device *device)
 980 {
 981         struct firmware *firmware;
 982         struct firmware_buf *buf;
 983         int ret;
 984
 985         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
 986         if (!firmware) {
 987                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
 988                         __func__);
 989                 return -ENOMEM;
 990         }
 991
 992         if (fw_get_builtin_firmware(firmware, name)) {
 993                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
 994                 return 0; /* assigned */
 995         }
 996
 997         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
 998
 999         /*
1000          * bind with 'buf' now to avoid warning in failure path
1001          * of requesting firmware.
1002          */
1003         firmware->priv = buf;
1004
1005         if (ret > 0) {
1006                 ret = sync_cached_firmware_buf(buf);
1007                 if (!ret) {
1008                         fw_set_page_data(buf, firmware);
1009                         return 0; /* assigned */
1010                 }
1011         }
1012
1013         if (ret < 0)
1014                 return ret;
1015         return 1; /* need to load */
1016 }
1017
1018 static int assign_firmware_buf(struct firmware *fw, struct device *device,
1019                                 bool skip_cache)
1020 {
1021         struct firmware_buf *buf = fw->priv;
1022
1023         mutex_lock(&fw_lock);
1024         if (!buf->size || is_fw_load_aborted(buf)) {
1025                 mutex_unlock(&fw_lock);
1026                 return -ENOENT;
1027         }
1028
1029         /*
1030          * add firmware name into devres list so that we can auto cache
1031          * and uncache firmware for device.
1032          *
1033          * device may has been deleted already, but the problem
1034          * should be fixed in devres or driver core.
1035          */
1036         if (device && !skip_cache)
1037                 fw_add_devm_name(device, buf->fw_id);
1038
1039         /*
1040          * After caching firmware image is started, let it piggyback
1041          * on request firmware.
1042          */
1043         if (buf->fwc->state == FW_LOADER_START_CACHE) {
1044                 if (fw_cache_piggyback_on_request(buf->fw_id))
1045                         kref_get(&buf->ref);
1046         }
1047
1048         /* pass the pages buffer to driver at the last minute */
1049         fw_set_page_data(buf, fw);
1050         mutex_unlock(&fw_lock);
1051         return 0;
1052 }
1053
1054 /* called from request_firmware() and request_firmware_work_func() */
1055 static int
1056 _request_firmware(const struct firmware **firmware_p, const char *name,
1057                   struct device *device, bool uevent, bool nowait)
1058 {
1059         struct firmware *fw;
1060         long timeout;
1061         int ret;
1062
1063         if (!firmware_p)
1064                 return -EINVAL;
1065
1066         ret = _request_firmware_prepare(&fw, name, device);
1067         if (ret <= 0) /* error or already assigned */
1068                 goto out;
1069
1070         ret = 0;
1071         timeout = firmware_loading_timeout();
1072         if (nowait) {
1073                 timeout = usermodehelper_read_lock_wait(timeout);
1074                 if (!timeout) {
1075                         dev_dbg(device, "firmware: %s loading timed out\n",
1076                                 name);
1077                         ret = -EBUSY;
1078                         goto out;
1079                 }
1080         } else {
1081                 ret = usermodehelper_read_trylock();
1082                 if (WARN_ON(ret)) {
1083                         dev_err(device, "firmware: %s will not be loaded\n",
1084                                 name);
1085                         goto out;
1086                 }
1087         }
1088
1089         if (!fw_get_filesystem_firmware(device, fw->priv))
1090                 ret = fw_load_from_user_helper(fw, name, device,
1091                                                uevent, nowait, timeout);
1092
1093         /* don't cache firmware handled without uevent */
1094         if (!ret)
1095                 ret = assign_firmware_buf(fw, device, !uevent);
1096
1097         usermodehelper_read_unlock();
1098
1099  out:
1100         if (ret < 0) {
1101                 release_firmware(fw);
1102                 fw = NULL;
1103         }
1104
1105         *firmware_p = fw;
1106         return ret;
1107 }
1108
1109 /**
1110  * request_firmware: - send firmware request and wait for it
1111  * @firmware_p: pointer to firmware image
1112  * @name: name of firmware file
1113  * @device: device for which firmware is being loaded
1114  *
1115  *      @firmware_p will be used to return a firmware image by the name
1116  *      of @name for device @device.
1117  *
1118  *      Should be called from user context where sleeping is allowed.
1119  *
1120  *      @name will be used as $FIRMWARE in the uevent environment and
1121  *      should be distinctive enough not to be confused with any other
1122  *      firmware image for this or any other device.
1123  *
1124  *      Caller must hold the reference count of @device.
1125  *
1126  *      The function can be called safely inside device's suspend and
1127  *      resume callback.
1128  **/
1129 int
1130 request_firmware(const struct firmware **firmware_p, const char *name,
1131                  struct device *device)
1132 {
1133         int ret;
1134
1135         /* Need to pin this module until return */
1136         __module_get(THIS_MODULE);
1137         ret = _request_firmware(firmware_p, name, device, true, false);
1138         module_put(THIS_MODULE);
1139         return ret;
1140 }
1141 EXPORT_SYMBOL(request_firmware);
1142
1143 /**
1144  * release_firmware: - release the resource associated with a firmware image
1145  * @fw: firmware resource to release
1146  **/
1147 void release_firmware(const struct firmware *fw)
1148 {
1149         if (fw) {
1150                 if (!fw_is_builtin_firmware(fw))
1151                         firmware_free_data(fw);
1152                 kfree(fw);
1153         }
1154 }
1155 EXPORT_SYMBOL(release_firmware);
1156
1157 /* Async support */
1158 struct firmware_work {
1159         struct work_struct work;
1160         struct module *module;
1161         const char *name;
1162         struct device *device;
1163         void *context;
1164         void (*cont)(const struct firmware *fw, void *context);
1165         bool uevent;
1166 };
1167
1168 static void request_firmware_work_func(struct work_struct *work)
1169 {
1170         struct firmware_work *fw_work;
1171         const struct firmware *fw;
1172
1173         fw_work = container_of(work, struct firmware_work, work);
1174
1175         _request_firmware(&fw, fw_work->name, fw_work->device,
1176                           fw_work->uevent, true);
1177         fw_work->cont(fw, fw_work->context);
1178         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1179
1180         module_put(fw_work->module);
1181         kfree(fw_work);
1182 }
1183
1184 /**
1185  * request_firmware_nowait - asynchronous version of request_firmware
1186  * @module: module requesting the firmware
1187  * @uevent: sends uevent to copy the firmware image if this flag
1188  *      is non-zero else the firmware copy must be done manually.
1189  * @name: name of firmware file
1190  * @device: device for which firmware is being loaded
1191  * @gfp: allocation flags
1192  * @context: will be passed over to @cont, and
1193  *      @fw may be %NULL if firmware request fails.
1194  * @cont: function will be called asynchronously when the firmware
1195  *      request is over.
1196  *
1197  *      Caller must hold the reference count of @device.
1198  *
1199  *      Asynchronous variant of request_firmware() for user contexts:
1200  *              - sleep for as small periods as possible since it may
1201  *              increase kernel boot time of built-in device drivers
1202  *              requesting firmware in their ->probe() methods, if
1203  *              @gfp is GFP_KERNEL.
1204  *
1205  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1206  **/
1207 int
1208 request_firmware_nowait(
1209         struct module *module, bool uevent,
1210         const char *name, struct device *device, gfp_t gfp, void *context,
1211         void (*cont)(const struct firmware *fw, void *context))
1212 {
1213         struct firmware_work *fw_work;
1214
1215         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1216         if (!fw_work)
1217                 return -ENOMEM;
1218
1219         fw_work->module = module;
1220         fw_work->name = name;
1221         fw_work->device = device;
1222         fw_work->context = context;
1223         fw_work->cont = cont;
1224         fw_work->uevent = uevent;
1225
1226         if (!try_module_get(module)) {
1227                 kfree(fw_work);
1228                 return -EFAULT;
1229         }
1230
1231         get_device(fw_work->device);
1232         INIT_WORK(&fw_work->work, request_firmware_work_func);
1233         schedule_work(&fw_work->work);
1234         return 0;
1235 }
1236 EXPORT_SYMBOL(request_firmware_nowait);
1237
1238 #ifdef CONFIG_PM_SLEEP
1239 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1240
1241 /**
1242  * cache_firmware - cache one firmware image in kernel memory space
1243  * @fw_name: the firmware image name
1244  *
1245  * Cache firmware in kernel memory so that drivers can use it when
1246  * system isn't ready for them to request firmware image from userspace.
1247  * Once it returns successfully, driver can use request_firmware or its
1248  * nowait version to get the cached firmware without any interacting
1249  * with userspace
1250  *
1251  * Return 0 if the firmware image has been cached successfully
1252  * Return !0 otherwise
1253  *
1254  */
1255 static int cache_firmware(const char *fw_name)
1256 {
1257         int ret;
1258         const struct firmware *fw;
1259
1260         pr_debug("%s: %s\n", __func__, fw_name);
1261
1262         ret = request_firmware(&fw, fw_name, NULL);
1263         if (!ret)
1264                 kfree(fw);
1265
1266         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1267
1268         return ret;
1269 }
1270
1271 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1272 {
1273         struct firmware_buf *tmp;
1274         struct firmware_cache *fwc = &fw_cache;
1275
1276         spin_lock(&fwc->lock);
1277         tmp = __fw_lookup_buf(fw_name);
1278         spin_unlock(&fwc->lock);
1279
1280         return tmp;
1281 }
1282
1283 /**
1284  * uncache_firmware - remove one cached firmware image
1285  * @fw_name: the firmware image name
1286  *
1287  * Uncache one firmware image which has been cached successfully
1288  * before.
1289  *
1290  * Return 0 if the firmware cache has been removed successfully
1291  * Return !0 otherwise
1292  *
1293  */
1294 static int uncache_firmware(const char *fw_name)
1295 {
1296         struct firmware_buf *buf;
1297         struct firmware fw;
1298
1299         pr_debug("%s: %s\n", __func__, fw_name);
1300
1301         if (fw_get_builtin_firmware(&fw, fw_name))
1302                 return 0;
1303
1304         buf = fw_lookup_buf(fw_name);
1305         if (buf) {
1306                 fw_free_buf(buf);
1307                 return 0;
1308         }
1309
1310         return -EINVAL;
1311 }
1312
1313 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1314 {
1315         struct fw_cache_entry *fce;
1316
1317         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1318         if (!fce)
1319                 goto exit;
1320
1321         strcpy(fce->name, name);
1322 exit:
1323         return fce;
1324 }
1325
1326 static int __fw_entry_found(const char *name)
1327 {
1328         struct firmware_cache *fwc = &fw_cache;
1329         struct fw_cache_entry *fce;
1330
1331         list_for_each_entry(fce, &fwc->fw_names, list) {
1332                 if (!strcmp(fce->name, name))
1333                         return 1;
1334         }
1335         return 0;
1336 }
1337
1338 static int fw_cache_piggyback_on_request(const char *name)
1339 {
1340         struct firmware_cache *fwc = &fw_cache;
1341         struct fw_cache_entry *fce;
1342         int ret = 0;
1343
1344         spin_lock(&fwc->name_lock);
1345         if (__fw_entry_found(name))
1346                 goto found;
1347
1348         fce = alloc_fw_cache_entry(name);
1349         if (fce) {
1350                 ret = 1;
1351                 list_add(&fce->list, &fwc->fw_names);
1352                 pr_debug("%s: fw: %s\n", __func__, name);
1353         }
1354 found:
1355         spin_unlock(&fwc->name_lock);
1356         return ret;
1357 }
1358
1359 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1360 {
1361         kfree(fce);
1362 }
1363
1364 static void __async_dev_cache_fw_image(void *fw_entry,
1365                                        async_cookie_t cookie)
1366 {
1367         struct fw_cache_entry *fce = fw_entry;
1368         struct firmware_cache *fwc = &fw_cache;
1369         int ret;
1370
1371         ret = cache_firmware(fce->name);
1372         if (ret) {
1373                 spin_lock(&fwc->name_lock);
1374                 list_del(&fce->list);
1375                 spin_unlock(&fwc->name_lock);
1376
1377                 free_fw_cache_entry(fce);
1378         }
1379 }
1380
1381 /* called with dev->devres_lock held */
1382 static void dev_create_fw_entry(struct device *dev, void *res,
1383                                 void *data)
1384 {
1385         struct fw_name_devm *fwn = res;
1386         const char *fw_name = fwn->name;
1387         struct list_head *head = data;
1388         struct fw_cache_entry *fce;
1389
1390         fce = alloc_fw_cache_entry(fw_name);
1391         if (fce)
1392                 list_add(&fce->list, head);
1393 }
1394
1395 static int devm_name_match(struct device *dev, void *res,
1396                            void *match_data)
1397 {
1398         struct fw_name_devm *fwn = res;
1399         return (fwn->magic == (unsigned long)match_data);
1400 }
1401
1402 static void dev_cache_fw_image(struct device *dev, void *data)
1403 {
1404         LIST_HEAD(todo);
1405         struct fw_cache_entry *fce;
1406         struct fw_cache_entry *fce_next;
1407         struct firmware_cache *fwc = &fw_cache;
1408
1409         devres_for_each_res(dev, fw_name_devm_release,
1410                             devm_name_match, &fw_cache,
1411                             dev_create_fw_entry, &todo);
1412
1413         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1414                 list_del(&fce->list);
1415
1416                 spin_lock(&fwc->name_lock);
1417                 /* only one cache entry for one firmware */
1418                 if (!__fw_entry_found(fce->name)) {
1419                         list_add(&fce->list, &fwc->fw_names);
1420                 } else {
1421                         free_fw_cache_entry(fce);
1422                         fce = NULL;
1423                 }
1424                 spin_unlock(&fwc->name_lock);
1425
1426                 if (fce)
1427                         async_schedule_domain(__async_dev_cache_fw_image,
1428                                               (void *)fce,
1429                                               &fw_cache_domain);
1430         }
1431 }
1432
1433 static void __device_uncache_fw_images(void)
1434 {
1435         struct firmware_cache *fwc = &fw_cache;
1436         struct fw_cache_entry *fce;
1437
1438         spin_lock(&fwc->name_lock);
1439         while (!list_empty(&fwc->fw_names)) {
1440                 fce = list_entry(fwc->fw_names.next,
1441                                 struct fw_cache_entry, list);
1442                 list_del(&fce->list);
1443                 spin_unlock(&fwc->name_lock);
1444
1445                 uncache_firmware(fce->name);
1446                 free_fw_cache_entry(fce);
1447
1448                 spin_lock(&fwc->name_lock);
1449         }
1450         spin_unlock(&fwc->name_lock);
1451 }
1452
1453 /**
1454  * device_cache_fw_images - cache devices' firmware
1455  *
1456  * If one device called request_firmware or its nowait version
1457  * successfully before, the firmware names are recored into the
1458  * device's devres link list, so device_cache_fw_images can call
1459  * cache_firmware() to cache these firmwares for the device,
1460  * then the device driver can load its firmwares easily at
1461  * time when system is not ready to complete loading firmware.
1462  */
1463 static void device_cache_fw_images(void)
1464 {
1465         struct firmware_cache *fwc = &fw_cache;
1466         int old_timeout;
1467         DEFINE_WAIT(wait);
1468
1469         pr_debug("%s\n", __func__);
1470
1471         /* cancel uncache work */
1472         cancel_delayed_work_sync(&fwc->work);
1473
1474         /*
1475          * use small loading timeout for caching devices' firmware
1476          * because all these firmware images have been loaded
1477          * successfully at lease once, also system is ready for
1478          * completing firmware loading now. The maximum size of
1479          * firmware in current distributions is about 2M bytes,
1480          * so 10 secs should be enough.
1481          */
1482         old_timeout = loading_timeout;
1483         loading_timeout = 10;
1484
1485         mutex_lock(&fw_lock);
1486         fwc->state = FW_LOADER_START_CACHE;
1487         dpm_for_each_dev(NULL, dev_cache_fw_image);
1488         mutex_unlock(&fw_lock);
1489
1490         /* wait for completion of caching firmware for all devices */
1491         async_synchronize_full_domain(&fw_cache_domain);
1492
1493         loading_timeout = old_timeout;
1494 }
1495
1496 /**
1497  * device_uncache_fw_images - uncache devices' firmware
1498  *
1499  * uncache all firmwares which have been cached successfully
1500  * by device_uncache_fw_images earlier
1501  */
1502 static void device_uncache_fw_images(void)
1503 {
1504         pr_debug("%s\n", __func__);
1505         __device_uncache_fw_images();
1506 }
1507
1508 static void device_uncache_fw_images_work(struct work_struct *work)
1509 {
1510         device_uncache_fw_images();
1511 }
1512
1513 /**
1514  * device_uncache_fw_images_delay - uncache devices firmwares
1515  * @delay: number of milliseconds to delay uncache device firmwares
1516  *
1517  * uncache all devices's firmwares which has been cached successfully
1518  * by device_cache_fw_images after @delay milliseconds.
1519  */
1520 static void device_uncache_fw_images_delay(unsigned long delay)
1521 {
1522         schedule_delayed_work(&fw_cache.work,
1523                         msecs_to_jiffies(delay));
1524 }
1525
1526 static int fw_pm_notify(struct notifier_block *notify_block,
1527                         unsigned long mode, void *unused)
1528 {
1529         switch (mode) {
1530         case PM_HIBERNATION_PREPARE:
1531         case PM_SUSPEND_PREPARE:
1532                 kill_requests_without_uevent();
1533                 device_cache_fw_images();
1534                 break;
1535
1536         case PM_POST_SUSPEND:
1537         case PM_POST_HIBERNATION:
1538         case PM_POST_RESTORE:
1539                 /*
1540                  * In case that system sleep failed and syscore_suspend is
1541                  * not called.
1542                  */
1543                 mutex_lock(&fw_lock);
1544                 fw_cache.state = FW_LOADER_NO_CACHE;
1545                 mutex_unlock(&fw_lock);
1546
1547                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1548                 break;
1549         }
1550
1551         return 0;
1552 }
1553
1554 /* stop caching firmware once syscore_suspend is reached */
1555 static int fw_suspend(void)
1556 {
1557         fw_cache.state = FW_LOADER_NO_CACHE;
1558         return 0;
1559 }
1560
1561 static struct syscore_ops fw_syscore_ops = {
1562         .suspend = fw_suspend,
1563 };
1564 #else
1565 static int fw_cache_piggyback_on_request(const char *name)
1566 {
1567         return 0;
1568 }
1569 #endif
1570
1571 static void __init fw_cache_init(void)
1572 {
1573         spin_lock_init(&fw_cache.lock);
1574         INIT_LIST_HEAD(&fw_cache.head);
1575         fw_cache.state = FW_LOADER_NO_CACHE;
1576
1577 #ifdef CONFIG_PM_SLEEP
1578         spin_lock_init(&fw_cache.name_lock);
1579         INIT_LIST_HEAD(&fw_cache.fw_names);
1580
1581         INIT_DELAYED_WORK(&fw_cache.work,
1582                           device_uncache_fw_images_work);
1583
1584         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1585         register_pm_notifier(&fw_cache.pm_notify);
1586
1587         register_syscore_ops(&fw_syscore_ops);
1588 #endif
1589 }
1590
1591 static int __init firmware_class_init(void)
1592 {
1593         fw_cache_init();
1594 #ifdef CONFIG_FW_LOADER_USER_HELPER
1595         register_reboot_notifier(&fw_shutdown_nb);
1596         return class_register(&firmware_class);
1597 #else
1598         return 0;
1599 #endif
1600 }
1601
1602 static void __exit firmware_class_exit(void)
1603 {
1604 #ifdef CONFIG_PM_SLEEP
1605         unregister_syscore_ops(&fw_syscore_ops);
1606         unregister_pm_notifier(&fw_cache.pm_notify);
1607 #endif
1608 #ifdef CONFIG_FW_LOADER_USER_HELPER
1609         unregister_reboot_notifier(&fw_shutdown_nb);
1610         class_unregister(&firmware_class);
1611 #endif
1612 }
1613
1614 fs_initcall(firmware_class_init);
1615 module_exit(firmware_class_exit);