drivers/base/firmware_class.c

   1 /*
   2  * firmware_class.c - Multi purpose firmware loading support
   3  *
   4  * Copyright (c) 2003 Manuel Estrada Sainz
   5  *
   6  * Please see Documentation/firmware_class/ for more information.
   7  *
   8  */
   9
  10 #include <linux/capability.h>
  11 #include <linux/device.h>
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/timer.h>
  15 #include <linux/vmalloc.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/bitops.h>
  18 #include <linux/mutex.h>
  19 #include <linux/workqueue.h>
  20 #include <linux/highmem.h>
  21 #include <linux/firmware.h>
  22 #include <linux/slab.h>
  23 #include <linux/sched.h>
  24 #include <linux/file.h>
  25 #include <linux/list.h>
  26 #include <linux/async.h>
  27 #include <linux/pm.h>
  28 #include <linux/suspend.h>
  29 #include <linux/syscore_ops.h>
  30
  31 #include <generated/utsrelease.h>
  32
  33 #include "base.h"
  34
  35 MODULE_AUTHOR("Manuel Estrada Sainz");
  36 MODULE_DESCRIPTION("Multi purpose firmware loading support");
  37 MODULE_LICENSE("GPL");
  38
  39 /* Builtin firmware support */
  40
  41 #ifdef CONFIG_FW_LOADER
  42
  43 extern struct builtin_fw __start_builtin_fw[];
  44 extern struct builtin_fw __end_builtin_fw[];
  45
  46 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  47 {
  48         struct builtin_fw *b_fw;
  49
  50         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
  51                 if (strcmp(name, b_fw->name) == 0) {
  52                         fw->size = b_fw->size;
  53                         fw->data = b_fw->data;
  54                         return true;
  55                 }
  56         }
  57
  58         return false;
  59 }
  60
  61 static bool fw_is_builtin_firmware(const struct firmware *fw)
  62 {
  63         struct builtin_fw *b_fw;
  64
  65         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
  66                 if (fw->data == b_fw->data)
  67                         return true;
  68
  69         return false;
  70 }
  71
  72 #else /* Module case - no builtin firmware support */
  73
  74 static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  75 {
  76         return false;
  77 }
  78
  79 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
  80 {
  81         return false;
  82 }
  83 #endif
  84
  85 enum {
  86         FW_STATUS_LOADING,
  87         FW_STATUS_DONE,
  88         FW_STATUS_ABORT,
  89 };
  90
  91 static int loading_timeout = 60;        /* In seconds */
  92
  93 static inline long firmware_loading_timeout(void)
  94 {
  95         return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
  96 }
  97
  98 struct firmware_cache {
  99         /* firmware_buf instance will be added into the below list */
 100         spinlock_t lock;
 101         struct list_head head;
 102         int state;
 103
 104 #ifdef CONFIG_PM_SLEEP
 105         /*
 106          * Names of firmware images which have been cached successfully
 107          * will be added into the below list so that device uncache
 108          * helper can trace which firmware images have been cached
 109          * before.
 110          */
 111         spinlock_t name_lock;
 112         struct list_head fw_names;
 113
 114         struct delayed_work work;
 115
 116         struct notifier_block   pm_notify;
 117 #endif
 118 };
 119
 120 struct firmware_buf {
 121         struct kref ref;
 122         struct list_head list;
 123         struct completion completion;
 124         struct firmware_cache *fwc;
 125         unsigned long status;
 126         void *data;
 127         size_t size;
 128 #ifdef CONFIG_FW_LOADER_USER_HELPER
 129         bool is_paged_buf;
 130         struct page **pages;
 131         int nr_pages;
 132         int page_array_size;
 133 #endif
 134         char fw_id[];
 135 };
 136
 137 struct fw_cache_entry {
 138         struct list_head list;
 139         char name[];
 140 };
 141
 142 struct fw_name_devm {
 143         unsigned long magic;
 144         char name[];
 145 };
 146
 147 #define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
 148
 149 #define FW_LOADER_NO_CACHE      0
 150 #define FW_LOADER_START_CACHE   1
 151
 152 static int fw_cache_piggyback_on_request(const char *name);
 153
 154 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
 155  * guarding for corner cases a global lock should be OK */
 156 static DEFINE_MUTEX(fw_lock);
 157
 158 static struct firmware_cache fw_cache;
 159
 160 static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
 161                                               struct firmware_cache *fwc)
 162 {
 163         struct firmware_buf *buf;
 164
 165         buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1 , GFP_ATOMIC);
 166
 167         if (!buf)
 168                 return buf;
 169
 170         kref_init(&buf->ref);
 171         strcpy(buf->fw_id, fw_name);
 172         buf->fwc = fwc;
 173         init_completion(&buf->completion);
 174
 175         pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
 176
 177         return buf;
 178 }
 179
 180 static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
 181 {
 182         struct firmware_buf *tmp;
 183         struct firmware_cache *fwc = &fw_cache;
 184
 185         list_for_each_entry(tmp, &fwc->head, list)
 186                 if (!strcmp(tmp->fw_id, fw_name))
 187                         return tmp;
 188         return NULL;
 189 }
 190
 191 static int fw_lookup_and_allocate_buf(const char *fw_name,
 192                                       struct firmware_cache *fwc,
 193                                       struct firmware_buf **buf)
 194 {
 195         struct firmware_buf *tmp;
 196
 197         spin_lock(&fwc->lock);
 198         tmp = __fw_lookup_buf(fw_name);
 199         if (tmp) {
 200                 kref_get(&tmp->ref);
 201                 spin_unlock(&fwc->lock);
 202                 *buf = tmp;
 203                 return 1;
 204         }
 205         tmp = __allocate_fw_buf(fw_name, fwc);
 206         if (tmp)
 207                 list_add(&tmp->list, &fwc->head);
 208         spin_unlock(&fwc->lock);
 209
 210         *buf = tmp;
 211
 212         return tmp ? 0 : -ENOMEM;
 213 }
 214
 215 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
 216 {
 217         struct firmware_buf *tmp;
 218         struct firmware_cache *fwc = &fw_cache;
 219
 220         spin_lock(&fwc->lock);
 221         tmp = __fw_lookup_buf(fw_name);
 222         spin_unlock(&fwc->lock);
 223
 224         return tmp;
 225 }
 226
 227 static void __fw_free_buf(struct kref *ref)
 228 {
 229         struct firmware_buf *buf = to_fwbuf(ref);
 230         struct firmware_cache *fwc = buf->fwc;
 231
 232         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 233                  __func__, buf->fw_id, buf, buf->data,
 234                  (unsigned int)buf->size);
 235
 236         list_del(&buf->list);
 237         spin_unlock(&fwc->lock);
 238
 239 #ifdef CONFIG_FW_LOADER_USER_HELPER
 240         if (buf->is_paged_buf) {
 241                 int i;
 242                 vunmap(buf->data);
 243                 for (i = 0; i < buf->nr_pages; i++)
 244                         __free_page(buf->pages[i]);
 245                 kfree(buf->pages);
 246         } else
 247 #endif
 248                 vfree(buf->data);
 249         kfree(buf);
 250 }
 251
 252 static void fw_free_buf(struct firmware_buf *buf)
 253 {
 254         struct firmware_cache *fwc = buf->fwc;
 255         spin_lock(&fwc->lock);
 256         if (!kref_put(&buf->ref, __fw_free_buf))
 257                 spin_unlock(&fwc->lock);
 258 }
 259
 260 /* direct firmware loading support */
 261 static char fw_path_para[256];
 262 static const char * const fw_path[] = {
 263         fw_path_para,
 264         "/lib/firmware/updates/" UTS_RELEASE,
 265         "/lib/firmware/updates",
 266         "/lib/firmware/" UTS_RELEASE,
 267         "/lib/firmware"
 268 };
 269
 270 /*
 271  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 272  * from kernel command line because firmware_class is generally built in
 273  * kernel instead of module.
 274  */
 275 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 276 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 277
 278 /* Don't inline this: 'struct kstat' is biggish */
 279 static noinline_for_stack long fw_file_size(struct file *file)
 280 {
 281         struct kstat st;
 282         if (vfs_getattr(&file->f_path, &st))
 283                 return -1;
 284         if (!S_ISREG(st.mode))
 285                 return -1;
 286         if (st.size != (long)st.size)
 287                 return -1;
 288         return st.size;
 289 }
 290
 291 static bool fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
 292 {
 293         long size;
 294         char *buf;
 295
 296         size = fw_file_size(file);
 297         if (size <= 0)
 298                 return false;
 299         buf = vmalloc(size);
 300         if (!buf)
 301                 return false;
 302         if (kernel_read(file, 0, buf, size) != size) {
 303                 vfree(buf);
 304                 return false;
 305         }
 306         fw_buf->data = buf;
 307         fw_buf->size = size;
 308         return true;
 309 }
 310
 311 static bool fw_get_filesystem_firmware(struct device *device,
 312                                        struct firmware_buf *buf)
 313 {
 314         int i;
 315         bool success = false;
 316         char *path = __getname();
 317
 318         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 319                 struct file *file;
 320
 321                 /* skip the unset customized path */
 322                 if (!fw_path[i][0])
 323                         continue;
 324
 325                 snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
 326
 327                 file = filp_open(path, O_RDONLY, 0);
 328                 if (IS_ERR(file))
 329                         continue;
 330                 success = fw_read_file_contents(file, buf);
 331                 fput(file);
 332                 if (success)
 333                         break;
 334         }
 335         __putname(path);
 336
 337         if (success) {
 338                 dev_dbg(device, "firmware: direct-loading firmware %s\n",
 339                         buf->fw_id);
 340                 mutex_lock(&fw_lock);
 341                 set_bit(FW_STATUS_DONE, &buf->status);
 342                 complete_all(&buf->completion);
 343                 mutex_unlock(&fw_lock);
 344         }
 345
 346         return success;
 347 }
 348
 349 /* firmware holds the ownership of pages */
 350 static void firmware_free_data(const struct firmware *fw)
 351 {
 352         /* Loaded directly? */
 353         if (!fw->priv) {
 354                 vfree(fw->data);
 355                 return;
 356         }
 357         fw_free_buf(fw->priv);
 358 }
 359
 360 /* store the pages buffer info firmware from buf */
 361 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
 362 {
 363         fw->priv = buf;
 364 #ifdef CONFIG_FW_LOADER_USER_HELPER
 365         fw->pages = buf->pages;
 366 #endif
 367         fw->size = buf->size;
 368         fw->data = buf->data;
 369
 370         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 371                  __func__, buf->fw_id, buf, buf->data,
 372                  (unsigned int)buf->size);
 373 }
 374
 375 #ifdef CONFIG_PM_SLEEP
 376 static void fw_name_devm_release(struct device *dev, void *res)
 377 {
 378         struct fw_name_devm *fwn = res;
 379
 380         if (fwn->magic == (unsigned long)&fw_cache)
 381                 pr_debug("%s: fw_name-%s devm-%p released\n",
 382                                 __func__, fwn->name, res);
 383 }
 384
 385 static int fw_devm_match(struct device *dev, void *res,
 386                 void *match_data)
 387 {
 388         struct fw_name_devm *fwn = res;
 389
 390         return (fwn->magic == (unsigned long)&fw_cache) &&
 391                 !strcmp(fwn->name, match_data);
 392 }
 393
 394 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 395                 const char *name)
 396 {
 397         struct fw_name_devm *fwn;
 398
 399         fwn = devres_find(dev, fw_name_devm_release,
 400                           fw_devm_match, (void *)name);
 401         return fwn;
 402 }
 403
 404 /* add firmware name into devres list */
 405 static int fw_add_devm_name(struct device *dev, const char *name)
 406 {
 407         struct fw_name_devm *fwn;
 408
 409         fwn = fw_find_devm_name(dev, name);
 410         if (fwn)
 411                 return 1;
 412
 413         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
 414                            strlen(name) + 1, GFP_KERNEL);
 415         if (!fwn)
 416                 return -ENOMEM;
 417
 418         fwn->magic = (unsigned long)&fw_cache;
 419         strcpy(fwn->name, name);
 420         devres_add(dev, fwn);
 421
 422         return 0;
 423 }
 424 #else
 425 static int fw_add_devm_name(struct device *dev, const char *name)
 426 {
 427         return 0;
 428 }
 429 #endif
 430
 431
 432 /*
 433  * user-mode helper code
 434  */
 435 #ifdef CONFIG_FW_LOADER_USER_HELPER
 436 struct firmware_priv {
 437         struct delayed_work timeout_work;
 438         bool nowait;
 439         struct device dev;
 440         struct firmware_buf *buf;
 441         struct firmware *fw;
 442 };
 443
 444 static struct firmware_priv *to_firmware_priv(struct device *dev)
 445 {
 446         return container_of(dev, struct firmware_priv, dev);
 447 }
 448
 449 static void fw_load_abort(struct firmware_priv *fw_priv)
 450 {
 451         struct firmware_buf *buf = fw_priv->buf;
 452
 453         set_bit(FW_STATUS_ABORT, &buf->status);
 454         complete_all(&buf->completion);
 455 }
 456
 457 #define is_fw_load_aborted(buf) \
 458         test_bit(FW_STATUS_ABORT, &(buf)->status)
 459
 460 static ssize_t firmware_timeout_show(struct class *class,
 461                                      struct class_attribute *attr,
 462                                      char *buf)
 463 {
 464         return sprintf(buf, "%d\n", loading_timeout);
 465 }
 466
 467 /**
 468  * firmware_timeout_store - set number of seconds to wait for firmware
 469  * @class: device class pointer
 470  * @attr: device attribute pointer
 471  * @buf: buffer to scan for timeout value
 472  * @count: number of bytes in @buf
 473  *
 474  *      Sets the number of seconds to wait for the firmware.  Once
 475  *      this expires an error will be returned to the driver and no
 476  *      firmware will be provided.
 477  *
 478  *      Note: zero means 'wait forever'.
 479  **/
 480 static ssize_t firmware_timeout_store(struct class *class,
 481                                       struct class_attribute *attr,
 482                                       const char *buf, size_t count)
 483 {
 484         loading_timeout = simple_strtol(buf, NULL, 10);
 485         if (loading_timeout < 0)
 486                 loading_timeout = 0;
 487
 488         return count;
 489 }
 490
 491 static struct class_attribute firmware_class_attrs[] = {
 492         __ATTR(timeout, S_IWUSR | S_IRUGO,
 493                 firmware_timeout_show, firmware_timeout_store),
 494         __ATTR_NULL
 495 };
 496
 497 static void fw_dev_release(struct device *dev)
 498 {
 499         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 500
 501         kfree(fw_priv);
 502
 503         module_put(THIS_MODULE);
 504 }
 505
 506 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 507 {
 508         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 509
 510         if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
 511                 return -ENOMEM;
 512         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
 513                 return -ENOMEM;
 514         if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
 515                 return -ENOMEM;
 516
 517         return 0;
 518 }
 519
 520 static struct class firmware_class = {
 521         .name           = "firmware",
 522         .class_attrs    = firmware_class_attrs,
 523         .dev_uevent     = firmware_uevent,
 524         .dev_release    = fw_dev_release,
 525 };
 526
 527 static ssize_t firmware_loading_show(struct device *dev,
 528                                      struct device_attribute *attr, char *buf)
 529 {
 530         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 531         int loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
 532
 533         return sprintf(buf, "%d\n", loading);
 534 }
 535
 536 /* Some architectures don't have PAGE_KERNEL_RO */
 537 #ifndef PAGE_KERNEL_RO
 538 #define PAGE_KERNEL_RO PAGE_KERNEL
 539 #endif
 540
 541 /* one pages buffer should be mapped/unmapped only once */
 542 static int fw_map_pages_buf(struct firmware_buf *buf)
 543 {
 544         if (!buf->is_paged_buf)
 545                 return 0;
 546
 547         if (buf->data)
 548                 vunmap(buf->data);
 549         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 550         if (!buf->data)
 551                 return -ENOMEM;
 552         return 0;
 553 }
 554
 555 /**
 556  * firmware_loading_store - set value in the 'loading' control file
 557  * @dev: device pointer
 558  * @attr: device attribute pointer
 559  * @buf: buffer to scan for loading control value
 560  * @count: number of bytes in @buf
 561  *
 562  *      The relevant values are:
 563  *
 564  *       1: Start a load, discarding any previous partial load.
 565  *       0: Conclude the load and hand the data to the driver code.
 566  *      -1: Conclude the load with an error and discard any written data.
 567  **/
 568 static ssize_t firmware_loading_store(struct device *dev,
 569                                       struct device_attribute *attr,
 570                                       const char *buf, size_t count)
 571 {
 572         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 573         struct firmware_buf *fw_buf = fw_priv->buf;
 574         int loading = simple_strtol(buf, NULL, 10);
 575         int i;
 576
 577         mutex_lock(&fw_lock);
 578
 579         if (!fw_buf)
 580                 goto out;
 581
 582         switch (loading) {
 583         case 1:
 584                 /* discarding any previous partial load */
 585                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
 586                         for (i = 0; i < fw_buf->nr_pages; i++)
 587                                 __free_page(fw_buf->pages[i]);
 588                         kfree(fw_buf->pages);
 589                         fw_buf->pages = NULL;
 590                         fw_buf->page_array_size = 0;
 591                         fw_buf->nr_pages = 0;
 592                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
 593                 }
 594                 break;
 595         case 0:
 596                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
 597                         set_bit(FW_STATUS_DONE, &fw_buf->status);
 598                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
 599
 600                         /*
 601                          * Several loading requests may be pending on
 602                          * one same firmware buf, so let all requests
 603                          * see the mapped 'buf->data' once the loading
 604                          * is completed.
 605                          * */
 606                         fw_map_pages_buf(fw_buf);
 607                         complete_all(&fw_buf->completion);
 608                         break;
 609                 }
 610                 /* fallthrough */
 611         default:
 612                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 613                 /* fallthrough */
 614         case -1:
 615                 fw_load_abort(fw_priv);
 616                 break;
 617         }
 618 out:
 619         mutex_unlock(&fw_lock);
 620         return count;
 621 }
 622
 623 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 624
 625 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 626                                   struct bin_attribute *bin_attr,
 627                                   char *buffer, loff_t offset, size_t count)
 628 {
 629         struct device *dev = kobj_to_dev(kobj);
 630         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 631         struct firmware_buf *buf;
 632         ssize_t ret_count;
 633
 634         mutex_lock(&fw_lock);
 635         buf = fw_priv->buf;
 636         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 637                 ret_count = -ENODEV;
 638                 goto out;
 639         }
 640         if (offset > buf->size) {
 641                 ret_count = 0;
 642                 goto out;
 643         }
 644         if (count > buf->size - offset)
 645                 count = buf->size - offset;
 646
 647         ret_count = count;
 648
 649         while (count) {
 650                 void *page_data;
 651                 int page_nr = offset >> PAGE_SHIFT;
 652                 int page_ofs = offset & (PAGE_SIZE-1);
 653                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 654
 655                 page_data = kmap(buf->pages[page_nr]);
 656
 657                 memcpy(buffer, page_data + page_ofs, page_cnt);
 658
 659                 kunmap(buf->pages[page_nr]);
 660                 buffer += page_cnt;
 661                 offset += page_cnt;
 662                 count -= page_cnt;
 663         }
 664 out:
 665         mutex_unlock(&fw_lock);
 666         return ret_count;
 667 }
 668
 669 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 670 {
 671         struct firmware_buf *buf = fw_priv->buf;
 672         int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
 673
 674         /* If the array of pages is too small, grow it... */
 675         if (buf->page_array_size < pages_needed) {
 676                 int new_array_size = max(pages_needed,
 677                                          buf->page_array_size * 2);
 678                 struct page **new_pages;
 679
 680                 new_pages = kmalloc(new_array_size * sizeof(void *),
 681                                     GFP_KERNEL);
 682                 if (!new_pages) {
 683                         fw_load_abort(fw_priv);
 684                         return -ENOMEM;
 685                 }
 686                 memcpy(new_pages, buf->pages,
 687                        buf->page_array_size * sizeof(void *));
 688                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 689                        (new_array_size - buf->page_array_size));
 690                 kfree(buf->pages);
 691                 buf->pages = new_pages;
 692                 buf->page_array_size = new_array_size;
 693         }
 694
 695         while (buf->nr_pages < pages_needed) {
 696                 buf->pages[buf->nr_pages] =
 697                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 698
 699                 if (!buf->pages[buf->nr_pages]) {
 700                         fw_load_abort(fw_priv);
 701                         return -ENOMEM;
 702                 }
 703                 buf->nr_pages++;
 704         }
 705         return 0;
 706 }
 707
 708 /**
 709  * firmware_data_write - write method for firmware
 710  * @filp: open sysfs file
 711  * @kobj: kobject for the device
 712  * @bin_attr: bin_attr structure
 713  * @buffer: buffer being written
 714  * @offset: buffer offset for write in total data store area
 715  * @count: buffer size
 716  *
 717  *      Data written to the 'data' attribute will be later handed to
 718  *      the driver as a firmware image.
 719  **/
 720 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 721                                    struct bin_attribute *bin_attr,
 722                                    char *buffer, loff_t offset, size_t count)
 723 {
 724         struct device *dev = kobj_to_dev(kobj);
 725         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 726         struct firmware_buf *buf;
 727         ssize_t retval;
 728
 729         if (!capable(CAP_SYS_RAWIO))
 730                 return -EPERM;
 731
 732         mutex_lock(&fw_lock);
 733         buf = fw_priv->buf;
 734         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 735                 retval = -ENODEV;
 736                 goto out;
 737         }
 738
 739         retval = fw_realloc_buffer(fw_priv, offset + count);
 740         if (retval)
 741                 goto out;
 742
 743         retval = count;
 744
 745         while (count) {
 746                 void *page_data;
 747                 int page_nr = offset >> PAGE_SHIFT;
 748                 int page_ofs = offset & (PAGE_SIZE - 1);
 749                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 750
 751                 page_data = kmap(buf->pages[page_nr]);
 752
 753                 memcpy(page_data + page_ofs, buffer, page_cnt);
 754
 755                 kunmap(buf->pages[page_nr]);
 756                 buffer += page_cnt;
 757                 offset += page_cnt;
 758                 count -= page_cnt;
 759         }
 760
 761         buf->size = max_t(size_t, offset, buf->size);
 762 out:
 763         mutex_unlock(&fw_lock);
 764         return retval;
 765 }
 766
 767 static struct bin_attribute firmware_attr_data = {
 768         .attr = { .name = "data", .mode = 0644 },
 769         .size = 0,
 770         .read = firmware_data_read,
 771         .write = firmware_data_write,
 772 };
 773
 774 static void firmware_class_timeout_work(struct work_struct *work)
 775 {
 776         struct firmware_priv *fw_priv = container_of(work,
 777                         struct firmware_priv, timeout_work.work);
 778
 779         mutex_lock(&fw_lock);
 780         if (test_bit(FW_STATUS_DONE, &(fw_priv->buf->status))) {
 781                 mutex_unlock(&fw_lock);
 782                 return;
 783         }
 784         fw_load_abort(fw_priv);
 785         mutex_unlock(&fw_lock);
 786 }
 787
 788 static struct firmware_priv *
 789 fw_create_instance(struct firmware *firmware, const char *fw_name,
 790                    struct device *device, bool uevent, bool nowait)
 791 {
 792         struct firmware_priv *fw_priv;
 793         struct device *f_dev;
 794
 795         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 796         if (!fw_priv) {
 797                 dev_err(device, "%s: kmalloc failed\n", __func__);
 798                 fw_priv = ERR_PTR(-ENOMEM);
 799                 goto exit;
 800         }
 801
 802         fw_priv->nowait = nowait;
 803         fw_priv->fw = firmware;
 804         INIT_DELAYED_WORK(&fw_priv->timeout_work,
 805                 firmware_class_timeout_work);
 806
 807         f_dev = &fw_priv->dev;
 808
 809         device_initialize(f_dev);
 810         dev_set_name(f_dev, "%s", fw_name);
 811         f_dev->parent = device;
 812         f_dev->class = &firmware_class;
 813 exit:
 814         return fw_priv;
 815 }
 816
 817 /* load a firmware via user helper */
 818 static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
 819                                   long timeout)
 820 {
 821         int retval = 0;
 822         struct device *f_dev = &fw_priv->dev;
 823         struct firmware_buf *buf = fw_priv->buf;
 824
 825         /* fall back on userspace loading */
 826         buf->is_paged_buf = true;
 827
 828         dev_set_uevent_suppress(f_dev, true);
 829
 830         /* Need to pin this module until class device is destroyed */
 831         __module_get(THIS_MODULE);
 832
 833         retval = device_add(f_dev);
 834         if (retval) {
 835                 dev_err(f_dev, "%s: device_register failed\n", __func__);
 836                 goto err_put_dev;
 837         }
 838
 839         retval = device_create_bin_file(f_dev, &firmware_attr_data);
 840         if (retval) {
 841                 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
 842                 goto err_del_dev;
 843         }
 844
 845         retval = device_create_file(f_dev, &dev_attr_loading);
 846         if (retval) {
 847                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
 848                 goto err_del_bin_attr;
 849         }
 850
 851         if (uevent) {
 852                 dev_set_uevent_suppress(f_dev, false);
 853                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
 854                 if (timeout != MAX_SCHEDULE_TIMEOUT)
 855                         schedule_delayed_work(&fw_priv->timeout_work, timeout);
 856
 857                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 858         }
 859
 860         wait_for_completion(&buf->completion);
 861
 862         cancel_delayed_work_sync(&fw_priv->timeout_work);
 863
 864         fw_priv->buf = NULL;
 865
 866         device_remove_file(f_dev, &dev_attr_loading);
 867 err_del_bin_attr:
 868         device_remove_bin_file(f_dev, &firmware_attr_data);
 869 err_del_dev:
 870         device_del(f_dev);
 871 err_put_dev:
 872         put_device(f_dev);
 873         return retval;
 874 }
 875
 876 static int fw_load_from_user_helper(struct firmware *firmware,
 877                                     const char *name, struct device *device,
 878                                     bool uevent, bool nowait, long timeout)
 879 {
 880         struct firmware_priv *fw_priv;
 881
 882         fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
 883         if (IS_ERR(fw_priv))
 884                 return PTR_ERR(fw_priv);
 885
 886         fw_priv->buf = firmware->priv;
 887         return _request_firmware_load(fw_priv, uevent, timeout);
 888 }
 889 #else /* CONFIG_FW_LOADER_USER_HELPER */
 890 static inline int
 891 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 892                          struct device *device, bool uevent, bool nowait,
 893                          long timeout)
 894 {
 895         return -ENOENT;
 896 }
 897
 898 /* No abort during direct loading */
 899 #define is_fw_load_aborted(buf) false
 900
 901 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 902
 903
 904 /* wait until the shared firmware_buf becomes ready (or error) */
 905 static int sync_cached_firmware_buf(struct firmware_buf *buf)
 906 {
 907         int ret = 0;
 908
 909         mutex_lock(&fw_lock);
 910         while (!test_bit(FW_STATUS_DONE, &buf->status)) {
 911                 if (is_fw_load_aborted(buf)) {
 912                         ret = -ENOENT;
 913                         break;
 914                 }
 915                 mutex_unlock(&fw_lock);
 916                 wait_for_completion(&buf->completion);
 917                 mutex_lock(&fw_lock);
 918         }
 919         mutex_unlock(&fw_lock);
 920         return ret;
 921 }
 922
 923 /* prepare firmware and firmware_buf structs;
 924  * return 0 if a firmware is already assigned, 1 if need to load one,
 925  * or a negative error code
 926  */
 927 static int
 928 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
 929                           struct device *device)
 930 {
 931         struct firmware *firmware;
 932         struct firmware_buf *buf;
 933         int ret;
 934
 935         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
 936         if (!firmware) {
 937                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
 938                         __func__);
 939                 return -ENOMEM;
 940         }
 941
 942         if (fw_get_builtin_firmware(firmware, name)) {
 943                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
 944                 return 0; /* assigned */
 945         }
 946
 947         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
 948
 949         /*
 950          * bind with 'buf' now to avoid warning in failure path
 951          * of requesting firmware.
 952          */
 953         firmware->priv = buf;
 954
 955         if (ret > 0) {
 956                 ret = sync_cached_firmware_buf(buf);
 957                 if (!ret) {
 958                         fw_set_page_data(buf, firmware);
 959                         return 0; /* assigned */
 960                 }
 961         }
 962
 963         if (ret < 0)
 964                 return ret;
 965         return 1; /* need to load */
 966 }
 967
 968 static int assign_firmware_buf(struct firmware *fw, struct device *device)
 969 {
 970         struct firmware_buf *buf = fw->priv;
 971
 972         mutex_lock(&fw_lock);
 973         if (!buf->size || is_fw_load_aborted(buf)) {
 974                 mutex_unlock(&fw_lock);
 975                 return -ENOENT;
 976         }
 977
 978         /*
 979          * add firmware name into devres list so that we can auto cache
 980          * and uncache firmware for device.
 981          *
 982          * device may has been deleted already, but the problem
 983          * should be fixed in devres or driver core.
 984          */
 985         if (device)
 986                 fw_add_devm_name(device, buf->fw_id);
 987
 988         /*
 989          * After caching firmware image is started, let it piggyback
 990          * on request firmware.
 991          */
 992         if (buf->fwc->state == FW_LOADER_START_CACHE) {
 993                 if (fw_cache_piggyback_on_request(buf->fw_id))
 994                         kref_get(&buf->ref);
 995         }
 996
 997         /* pass the pages buffer to driver at the last minute */
 998         fw_set_page_data(buf, fw);
 999         mutex_unlock(&fw_lock);
1000         return 0;
1001 }
1002
1003 /* called from request_firmware() and request_firmware_work_func() */
1004 static int
1005 _request_firmware(const struct firmware **firmware_p, const char *name,
1006                   struct device *device, bool uevent, bool nowait)
1007 {
1008         struct firmware *fw;
1009         long timeout;
1010         int ret;
1011
1012         if (!firmware_p)
1013                 return -EINVAL;
1014
1015         ret = _request_firmware_prepare(&fw, name, device);
1016         if (ret <= 0) /* error or already assigned */
1017                 goto out;
1018
1019         ret = 0;
1020         timeout = firmware_loading_timeout();
1021         if (nowait) {
1022                 timeout = usermodehelper_read_lock_wait(timeout);
1023                 if (!timeout) {
1024                         dev_dbg(device, "firmware: %s loading timed out\n",
1025                                 name);
1026                         ret = -EBUSY;
1027                         goto out;
1028                 }
1029         } else {
1030                 ret = usermodehelper_read_trylock();
1031                 if (WARN_ON(ret)) {
1032                         dev_err(device, "firmware: %s will not be loaded\n",
1033                                 name);
1034                         goto out;
1035                 }
1036         }
1037
1038         if (!fw_get_filesystem_firmware(device, fw->priv))
1039                 ret = fw_load_from_user_helper(fw, name, device,
1040                                                uevent, nowait, timeout);
1041         if (!ret)
1042                 ret = assign_firmware_buf(fw, device);
1043
1044         usermodehelper_read_unlock();
1045
1046  out:
1047         if (ret < 0) {
1048                 release_firmware(fw);
1049                 fw = NULL;
1050         }
1051
1052         *firmware_p = fw;
1053         return ret;
1054 }
1055
1056 /**
1057  * request_firmware: - send firmware request and wait for it
1058  * @firmware_p: pointer to firmware image
1059  * @name: name of firmware file
1060  * @device: device for which firmware is being loaded
1061  *
1062  *      @firmware_p will be used to return a firmware image by the name
1063  *      of @name for device @device.
1064  *
1065  *      Should be called from user context where sleeping is allowed.
1066  *
1067  *      @name will be used as $FIRMWARE in the uevent environment and
1068  *      should be distinctive enough not to be confused with any other
1069  *      firmware image for this or any other device.
1070  *
1071  *      Caller must hold the reference count of @device.
1072  *
1073  *      The function can be called safely inside device's suspend and
1074  *      resume callback.
1075  **/
1076 int
1077 request_firmware(const struct firmware **firmware_p, const char *name,
1078                  struct device *device)
1079 {
1080         return _request_firmware(firmware_p, name, device, true, false);
1081 }
1082
1083 /**
1084  * release_firmware: - release the resource associated with a firmware image
1085  * @fw: firmware resource to release
1086  **/
1087 void release_firmware(const struct firmware *fw)
1088 {
1089         if (fw) {
1090                 if (!fw_is_builtin_firmware(fw))
1091                         firmware_free_data(fw);
1092                 kfree(fw);
1093         }
1094 }
1095
1096 /* Async support */
1097 struct firmware_work {
1098         struct work_struct work;
1099         struct module *module;
1100         const char *name;
1101         struct device *device;
1102         void *context;
1103         void (*cont)(const struct firmware *fw, void *context);
1104         bool uevent;
1105 };
1106
1107 static void request_firmware_work_func(struct work_struct *work)
1108 {
1109         struct firmware_work *fw_work;
1110         const struct firmware *fw;
1111
1112         fw_work = container_of(work, struct firmware_work, work);
1113
1114         _request_firmware(&fw, fw_work->name, fw_work->device,
1115                           fw_work->uevent, true);
1116         fw_work->cont(fw, fw_work->context);
1117         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1118
1119         module_put(fw_work->module);
1120         kfree(fw_work);
1121 }
1122
1123 /**
1124  * request_firmware_nowait - asynchronous version of request_firmware
1125  * @module: module requesting the firmware
1126  * @uevent: sends uevent to copy the firmware image if this flag
1127  *      is non-zero else the firmware copy must be done manually.
1128  * @name: name of firmware file
1129  * @device: device for which firmware is being loaded
1130  * @gfp: allocation flags
1131  * @context: will be passed over to @cont, and
1132  *      @fw may be %NULL if firmware request fails.
1133  * @cont: function will be called asynchronously when the firmware
1134  *      request is over.
1135  *
1136  *      Caller must hold the reference count of @device.
1137  *
1138  *      Asynchronous variant of request_firmware() for user contexts:
1139  *              - sleep for as small periods as possible since it may
1140  *              increase kernel boot time of built-in device drivers
1141  *              requesting firmware in their ->probe() methods, if
1142  *              @gfp is GFP_KERNEL.
1143  *
1144  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1145  **/
1146 int
1147 request_firmware_nowait(
1148         struct module *module, bool uevent,
1149         const char *name, struct device *device, gfp_t gfp, void *context,
1150         void (*cont)(const struct firmware *fw, void *context))
1151 {
1152         struct firmware_work *fw_work;
1153
1154         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1155         if (!fw_work)
1156                 return -ENOMEM;
1157
1158         fw_work->module = module;
1159         fw_work->name = name;
1160         fw_work->device = device;
1161         fw_work->context = context;
1162         fw_work->cont = cont;
1163         fw_work->uevent = uevent;
1164
1165         if (!try_module_get(module)) {
1166                 kfree(fw_work);
1167                 return -EFAULT;
1168         }
1169
1170         get_device(fw_work->device);
1171         INIT_WORK(&fw_work->work, request_firmware_work_func);
1172         schedule_work(&fw_work->work);
1173         return 0;
1174 }
1175
1176 /**
1177  * cache_firmware - cache one firmware image in kernel memory space
1178  * @fw_name: the firmware image name
1179  *
1180  * Cache firmware in kernel memory so that drivers can use it when
1181  * system isn't ready for them to request firmware image from userspace.
1182  * Once it returns successfully, driver can use request_firmware or its
1183  * nowait version to get the cached firmware without any interacting
1184  * with userspace
1185  *
1186  * Return 0 if the firmware image has been cached successfully
1187  * Return !0 otherwise
1188  *
1189  */
1190 int cache_firmware(const char *fw_name)
1191 {
1192         int ret;
1193         const struct firmware *fw;
1194
1195         pr_debug("%s: %s\n", __func__, fw_name);
1196
1197         ret = request_firmware(&fw, fw_name, NULL);
1198         if (!ret)
1199                 kfree(fw);
1200
1201         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1202
1203         return ret;
1204 }
1205
1206 /**
1207  * uncache_firmware - remove one cached firmware image
1208  * @fw_name: the firmware image name
1209  *
1210  * Uncache one firmware image which has been cached successfully
1211  * before.
1212  *
1213  * Return 0 if the firmware cache has been removed successfully
1214  * Return !0 otherwise
1215  *
1216  */
1217 int uncache_firmware(const char *fw_name)
1218 {
1219         struct firmware_buf *buf;
1220         struct firmware fw;
1221
1222         pr_debug("%s: %s\n", __func__, fw_name);
1223
1224         if (fw_get_builtin_firmware(&fw, fw_name))
1225                 return 0;
1226
1227         buf = fw_lookup_buf(fw_name);
1228         if (buf) {
1229                 fw_free_buf(buf);
1230                 return 0;
1231         }
1232
1233         return -EINVAL;
1234 }
1235
1236 #ifdef CONFIG_PM_SLEEP
1237 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1238
1239 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1240 {
1241         struct fw_cache_entry *fce;
1242
1243         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1244         if (!fce)
1245                 goto exit;
1246
1247         strcpy(fce->name, name);
1248 exit:
1249         return fce;
1250 }
1251
1252 static int __fw_entry_found(const char *name)
1253 {
1254         struct firmware_cache *fwc = &fw_cache;
1255         struct fw_cache_entry *fce;
1256
1257         list_for_each_entry(fce, &fwc->fw_names, list) {
1258                 if (!strcmp(fce->name, name))
1259                         return 1;
1260         }
1261         return 0;
1262 }
1263
1264 static int fw_cache_piggyback_on_request(const char *name)
1265 {
1266         struct firmware_cache *fwc = &fw_cache;
1267         struct fw_cache_entry *fce;
1268         int ret = 0;
1269
1270         spin_lock(&fwc->name_lock);
1271         if (__fw_entry_found(name))
1272                 goto found;
1273
1274         fce = alloc_fw_cache_entry(name);
1275         if (fce) {
1276                 ret = 1;
1277                 list_add(&fce->list, &fwc->fw_names);
1278                 pr_debug("%s: fw: %s\n", __func__, name);
1279         }
1280 found:
1281         spin_unlock(&fwc->name_lock);
1282         return ret;
1283 }
1284
1285 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1286 {
1287         kfree(fce);
1288 }
1289
1290 static void __async_dev_cache_fw_image(void *fw_entry,
1291                                        async_cookie_t cookie)
1292 {
1293         struct fw_cache_entry *fce = fw_entry;
1294         struct firmware_cache *fwc = &fw_cache;
1295         int ret;
1296
1297         ret = cache_firmware(fce->name);
1298         if (ret) {
1299                 spin_lock(&fwc->name_lock);
1300                 list_del(&fce->list);
1301                 spin_unlock(&fwc->name_lock);
1302
1303                 free_fw_cache_entry(fce);
1304         }
1305 }
1306
1307 /* called with dev->devres_lock held */
1308 static void dev_create_fw_entry(struct device *dev, void *res,
1309                                 void *data)
1310 {
1311         struct fw_name_devm *fwn = res;
1312         const char *fw_name = fwn->name;
1313         struct list_head *head = data;
1314         struct fw_cache_entry *fce;
1315
1316         fce = alloc_fw_cache_entry(fw_name);
1317         if (fce)
1318                 list_add(&fce->list, head);
1319 }
1320
1321 static int devm_name_match(struct device *dev, void *res,
1322                            void *match_data)
1323 {
1324         struct fw_name_devm *fwn = res;
1325         return (fwn->magic == (unsigned long)match_data);
1326 }
1327
1328 static void dev_cache_fw_image(struct device *dev, void *data)
1329 {
1330         LIST_HEAD(todo);
1331         struct fw_cache_entry *fce;
1332         struct fw_cache_entry *fce_next;
1333         struct firmware_cache *fwc = &fw_cache;
1334
1335         devres_for_each_res(dev, fw_name_devm_release,
1336                             devm_name_match, &fw_cache,
1337                             dev_create_fw_entry, &todo);
1338
1339         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1340                 list_del(&fce->list);
1341
1342                 spin_lock(&fwc->name_lock);
1343                 /* only one cache entry for one firmware */
1344                 if (!__fw_entry_found(fce->name)) {
1345                         list_add(&fce->list, &fwc->fw_names);
1346                 } else {
1347                         free_fw_cache_entry(fce);
1348                         fce = NULL;
1349                 }
1350                 spin_unlock(&fwc->name_lock);
1351
1352                 if (fce)
1353                         async_schedule_domain(__async_dev_cache_fw_image,
1354                                               (void *)fce,
1355                                               &fw_cache_domain);
1356         }
1357 }
1358
1359 static void __device_uncache_fw_images(void)
1360 {
1361         struct firmware_cache *fwc = &fw_cache;
1362         struct fw_cache_entry *fce;
1363
1364         spin_lock(&fwc->name_lock);
1365         while (!list_empty(&fwc->fw_names)) {
1366                 fce = list_entry(fwc->fw_names.next,
1367                                 struct fw_cache_entry, list);
1368                 list_del(&fce->list);
1369                 spin_unlock(&fwc->name_lock);
1370
1371                 uncache_firmware(fce->name);
1372                 free_fw_cache_entry(fce);
1373
1374                 spin_lock(&fwc->name_lock);
1375         }
1376         spin_unlock(&fwc->name_lock);
1377 }
1378
1379 /**
1380  * device_cache_fw_images - cache devices' firmware
1381  *
1382  * If one device called request_firmware or its nowait version
1383  * successfully before, the firmware names are recored into the
1384  * device's devres link list, so device_cache_fw_images can call
1385  * cache_firmware() to cache these firmwares for the device,
1386  * then the device driver can load its firmwares easily at
1387  * time when system is not ready to complete loading firmware.
1388  */
1389 static void device_cache_fw_images(void)
1390 {
1391         struct firmware_cache *fwc = &fw_cache;
1392         int old_timeout;
1393         DEFINE_WAIT(wait);
1394
1395         pr_debug("%s\n", __func__);
1396
1397         /* cancel uncache work */
1398         cancel_delayed_work_sync(&fwc->work);
1399
1400         /*
1401          * use small loading timeout for caching devices' firmware
1402          * because all these firmware images have been loaded
1403          * successfully at lease once, also system is ready for
1404          * completing firmware loading now. The maximum size of
1405          * firmware in current distributions is about 2M bytes,
1406          * so 10 secs should be enough.
1407          */
1408         old_timeout = loading_timeout;
1409         loading_timeout = 10;
1410
1411         mutex_lock(&fw_lock);
1412         fwc->state = FW_LOADER_START_CACHE;
1413         dpm_for_each_dev(NULL, dev_cache_fw_image);
1414         mutex_unlock(&fw_lock);
1415
1416         /* wait for completion of caching firmware for all devices */
1417         async_synchronize_full_domain(&fw_cache_domain);
1418
1419         loading_timeout = old_timeout;
1420 }
1421
1422 /**
1423  * device_uncache_fw_images - uncache devices' firmware
1424  *
1425  * uncache all firmwares which have been cached successfully
1426  * by device_uncache_fw_images earlier
1427  */
1428 static void device_uncache_fw_images(void)
1429 {
1430         pr_debug("%s\n", __func__);
1431         __device_uncache_fw_images();
1432 }
1433
1434 static void device_uncache_fw_images_work(struct work_struct *work)
1435 {
1436         device_uncache_fw_images();
1437 }
1438
1439 /**
1440  * device_uncache_fw_images_delay - uncache devices firmwares
1441  * @delay: number of milliseconds to delay uncache device firmwares
1442  *
1443  * uncache all devices's firmwares which has been cached successfully
1444  * by device_cache_fw_images after @delay milliseconds.
1445  */
1446 static void device_uncache_fw_images_delay(unsigned long delay)
1447 {
1448         schedule_delayed_work(&fw_cache.work,
1449                         msecs_to_jiffies(delay));
1450 }
1451
1452 static int fw_pm_notify(struct notifier_block *notify_block,
1453                         unsigned long mode, void *unused)
1454 {
1455         switch (mode) {
1456         case PM_HIBERNATION_PREPARE:
1457         case PM_SUSPEND_PREPARE:
1458                 device_cache_fw_images();
1459                 break;
1460
1461         case PM_POST_SUSPEND:
1462         case PM_POST_HIBERNATION:
1463         case PM_POST_RESTORE:
1464                 /*
1465                  * In case that system sleep failed and syscore_suspend is
1466                  * not called.
1467                  */
1468                 mutex_lock(&fw_lock);
1469                 fw_cache.state = FW_LOADER_NO_CACHE;
1470                 mutex_unlock(&fw_lock);
1471
1472                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1473                 break;
1474         }
1475
1476         return 0;
1477 }
1478
1479 /* stop caching firmware once syscore_suspend is reached */
1480 static int fw_suspend(void)
1481 {
1482         fw_cache.state = FW_LOADER_NO_CACHE;
1483         return 0;
1484 }
1485
1486 static struct syscore_ops fw_syscore_ops = {
1487         .suspend = fw_suspend,
1488 };
1489 #else
1490 static int fw_cache_piggyback_on_request(const char *name)
1491 {
1492         return 0;
1493 }
1494 #endif
1495
1496 static void __init fw_cache_init(void)
1497 {
1498         spin_lock_init(&fw_cache.lock);
1499         INIT_LIST_HEAD(&fw_cache.head);
1500         fw_cache.state = FW_LOADER_NO_CACHE;
1501
1502 #ifdef CONFIG_PM_SLEEP
1503         spin_lock_init(&fw_cache.name_lock);
1504         INIT_LIST_HEAD(&fw_cache.fw_names);
1505
1506         INIT_DELAYED_WORK(&fw_cache.work,
1507                           device_uncache_fw_images_work);
1508
1509         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1510         register_pm_notifier(&fw_cache.pm_notify);
1511
1512         register_syscore_ops(&fw_syscore_ops);
1513 #endif
1514 }
1515
1516 static int __init firmware_class_init(void)
1517 {
1518         fw_cache_init();
1519 #ifdef CONFIG_FW_LOADER_USER_HELPER
1520         return class_register(&firmware_class);
1521 #else
1522         return 0;
1523 #endif
1524 }
1525
1526 static void __exit firmware_class_exit(void)
1527 {
1528 #ifdef CONFIG_PM_SLEEP
1529         unregister_syscore_ops(&fw_syscore_ops);
1530         unregister_pm_notifier(&fw_cache.pm_notify);
1531 #endif
1532 #ifdef CONFIG_FW_LOADER_USER_HELPER
1533         class_unregister(&firmware_class);
1534 #endif
1535 }
1536
1537 fs_initcall(firmware_class_init);
1538 module_exit(firmware_class_exit);
1539
1540 EXPORT_SYMBOL(release_firmware);
1541 EXPORT_SYMBOL(request_firmware);
1542 EXPORT_SYMBOL(request_firmware_nowait);
1543 EXPORT_SYMBOL_GPL(cache_firmware);
1544 EXPORT_SYMBOL_GPL(uncache_firmware);