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