drivers/firmware/dell_rbu.c

   1 /*
   2  * dell_rbu.c
   3  * Bios Update driver for Dell systems
   4  * Author: Dell Inc
   5  *         Abhay Salunke <abhay_salunke@dell.com>
   6  *
   7  * Copyright (C) 2005 Dell Inc.
   8  *
   9  * Remote BIOS Update (rbu) driver is used for updating DELL BIOS by
  10  * creating entries in the /sys file systems on Linux 2.6 and higher
  11  * kernels. The driver supports two mechanism to update the BIOS namely
  12  * contiguous and packetized. Both these methods still require having some
  13  * application to set the CMOS bit indicating the BIOS to update itself
  14  * after a reboot.
  15  *
  16  * Contiguous method:
  17  * This driver writes the incoming data in a monolithic image by allocating
  18  * contiguous physical pages large enough to accommodate the incoming BIOS
  19  * image size.
  20  *
  21  * Packetized method:
  22  * The driver writes the incoming packet image by allocating a new packet
  23  * on every time the packet data is written. This driver requires an
  24  * application to break the BIOS image in to fixed sized packet chunks.
  25  *
  26  * See Documentation/dell_rbu.txt for more info.
  27  *
  28  * This program is free software; you can redistribute it and/or modify
  29  * it under the terms of the GNU General Public License v2.0 as published by
  30  * the Free Software Foundation
  31  *
  32  * This program is distributed in the hope that it will be useful,
  33  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  34  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  35  * GNU General Public License for more details.
  36  */
  37 #include <linux/init.h>
  38 #include <linux/module.h>
  39 #include <linux/string.h>
  40 #include <linux/errno.h>
  41 #include <linux/blkdev.h>
  42 #include <linux/platform_device.h>
  43 #include <linux/spinlock.h>
  44 #include <linux/moduleparam.h>
  45 #include <linux/firmware.h>
  46 #include <linux/dma-mapping.h>
  47
  48 MODULE_AUTHOR("Abhay Salunke <abhay_salunke@dell.com>");
  49 MODULE_DESCRIPTION("Driver for updating BIOS image on DELL systems");
  50 MODULE_LICENSE("GPL");
  51 MODULE_VERSION("3.2");
  52
  53 #define BIOS_SCAN_LIMIT 0xffffffff
  54 #define MAX_IMAGE_LENGTH 16
  55 static struct _rbu_data {
  56         void *image_update_buffer;
  57         unsigned long image_update_buffer_size;
  58         unsigned long bios_image_size;
  59         int image_update_ordernum;
  60         int dma_alloc;
  61         spinlock_t lock;
  62         unsigned long packet_read_count;
  63         unsigned long num_packets;
  64         unsigned long packetsize;
  65         unsigned long imagesize;
  66         int entry_created;
  67 } rbu_data;
  68
  69 static char image_type[MAX_IMAGE_LENGTH + 1] = "mono";
  70 module_param_string(image_type, image_type, sizeof (image_type), 0);
  71 MODULE_PARM_DESC(image_type,
  72         "BIOS image type. choose- mono or packet or init");
  73
  74 static unsigned long allocation_floor = 0x100000;
  75 module_param(allocation_floor, ulong, 0644);
  76 MODULE_PARM_DESC(allocation_floor,
  77     "Minimum address for allocations when using Packet mode");
  78
  79 struct packet_data {
  80         struct list_head list;
  81         size_t length;
  82         void *data;
  83         int ordernum;
  84 };
  85
  86 static struct packet_data packet_data_head;
  87
  88 static struct platform_device *rbu_device;
  89 static int context;
  90 static dma_addr_t dell_rbu_dmaaddr;
  91
  92 static void init_packet_head(void)
  93 {
  94         INIT_LIST_HEAD(&packet_data_head.list);
  95         rbu_data.packet_read_count = 0;
  96         rbu_data.num_packets = 0;
  97         rbu_data.packetsize = 0;
  98         rbu_data.imagesize = 0;
  99 }
 100
 101 static int create_packet(void *data, size_t length)
 102 {
 103         struct packet_data *newpacket;
 104         int ordernum = 0;
 105         int retval = 0;
 106         unsigned int packet_array_size = 0;
 107         void **invalid_addr_packet_array = NULL;
 108         void *packet_data_temp_buf = NULL;
 109         unsigned int idx = 0;
 110
 111         pr_debug("create_packet: entry \n");
 112
 113         if (!rbu_data.packetsize) {
 114                 pr_debug("create_packet: packetsize not specified\n");
 115                 retval = -EINVAL;
 116                 goto out_noalloc;
 117         }
 118
 119         spin_unlock(&rbu_data.lock);
 120
 121         newpacket = kzalloc(sizeof (struct packet_data), GFP_KERNEL);
 122
 123         if (!newpacket) {
 124                 printk(KERN_WARNING
 125                         "dell_rbu:%s: failed to allocate new "
 126                         "packet\n", __func__);
 127                 retval = -ENOMEM;
 128                 spin_lock(&rbu_data.lock);
 129                 goto out_noalloc;
 130         }
 131
 132         ordernum = get_order(length);
 133
 134         /*
 135          * BIOS errata mean we cannot allocate packets below 1MB or they will
 136          * be overwritten by BIOS.
 137          *
 138          * array to temporarily hold packets
 139          * that are below the allocation floor
 140          *
 141          * NOTE: very simplistic because we only need the floor to be at 1MB
 142          *       due to BIOS errata. This shouldn't be used for higher floors
 143          *       or you will run out of mem trying to allocate the array.
 144          */
 145         packet_array_size = max(
 146                         (unsigned int)(allocation_floor / rbu_data.packetsize),
 147                         (unsigned int)1);
 148         invalid_addr_packet_array = kzalloc(packet_array_size * sizeof(void*),
 149                                                 GFP_KERNEL);
 150
 151         if (!invalid_addr_packet_array) {
 152                 printk(KERN_WARNING
 153                         "dell_rbu:%s: failed to allocate "
 154                         "invalid_addr_packet_array \n",
 155                         __func__);
 156                 retval = -ENOMEM;
 157                 spin_lock(&rbu_data.lock);
 158                 goto out_alloc_packet;
 159         }
 160
 161         while (!packet_data_temp_buf) {
 162                 packet_data_temp_buf = (unsigned char *)
 163                         __get_free_pages(GFP_KERNEL, ordernum);
 164                 if (!packet_data_temp_buf) {
 165                         printk(KERN_WARNING
 166                                 "dell_rbu:%s: failed to allocate new "
 167                                 "packet\n", __func__);
 168                         retval = -ENOMEM;
 169                         spin_lock(&rbu_data.lock);
 170                         goto out_alloc_packet_array;
 171                 }
 172
 173                 if ((unsigned long)virt_to_phys(packet_data_temp_buf)
 174                                 < allocation_floor) {
 175                         pr_debug("packet 0x%lx below floor at 0x%lx.\n",
 176                                         (unsigned long)virt_to_phys(
 177                                                 packet_data_temp_buf),
 178                                         allocation_floor);
 179                         invalid_addr_packet_array[idx++] = packet_data_temp_buf;
 180                         packet_data_temp_buf = NULL;
 181                 }
 182         }
 183         spin_lock(&rbu_data.lock);
 184
 185         newpacket->data = packet_data_temp_buf;
 186
 187         pr_debug("create_packet: newpacket at physical addr %lx\n",
 188                 (unsigned long)virt_to_phys(newpacket->data));
 189
 190         /* packets may not have fixed size */
 191         newpacket->length = length;
 192         newpacket->ordernum = ordernum;
 193         ++rbu_data.num_packets;
 194
 195         /* initialize the newly created packet headers */
 196         INIT_LIST_HEAD(&newpacket->list);
 197         list_add_tail(&newpacket->list, &packet_data_head.list);
 198
 199         memcpy(newpacket->data, data, length);
 200
 201         pr_debug("create_packet: exit \n");
 202
 203 out_alloc_packet_array:
 204         /* always free packet array */
 205         for (;idx>0;idx--) {
 206                 pr_debug("freeing unused packet below floor 0x%lx.\n",
 207                         (unsigned long)virt_to_phys(
 208                                 invalid_addr_packet_array[idx-1]));
 209                 free_pages((unsigned long)invalid_addr_packet_array[idx-1],
 210                         ordernum);
 211         }
 212         kfree(invalid_addr_packet_array);
 213
 214 out_alloc_packet:
 215         /* if error, free data */
 216         if (retval)
 217                 kfree(newpacket);
 218
 219 out_noalloc:
 220         return retval;
 221 }
 222
 223 static int packetize_data(const u8 *data, size_t length)
 224 {
 225         int rc = 0;
 226         int done = 0;
 227         int packet_length;
 228         u8 *temp;
 229         u8 *end = (u8 *) data + length;
 230         pr_debug("packetize_data: data length %zd\n", length);
 231         if (!rbu_data.packetsize) {
 232                 printk(KERN_WARNING
 233                         "dell_rbu: packetsize not specified\n");
 234                 return -EIO;
 235         }
 236
 237         temp = (u8 *) data;
 238
 239         /* packetize the hunk */
 240         while (!done) {
 241                 if ((temp + rbu_data.packetsize) < end)
 242                         packet_length = rbu_data.packetsize;
 243                 else {
 244                         /* this is the last packet */
 245                         packet_length = end - temp;
 246                         done = 1;
 247                 }
 248
 249                 if ((rc = create_packet(temp, packet_length)))
 250                         return rc;
 251
 252                 pr_debug("%p:%td\n", temp, (end - temp));
 253                 temp += packet_length;
 254         }
 255
 256         rbu_data.imagesize = length;
 257
 258         return rc;
 259 }
 260
 261 static int do_packet_read(char *data, struct list_head *ptemp_list,
 262         int length, int bytes_read, int *list_read_count)
 263 {
 264         void *ptemp_buf;
 265         struct packet_data *newpacket = NULL;
 266         int bytes_copied = 0;
 267         int j = 0;
 268
 269         newpacket = list_entry(ptemp_list, struct packet_data, list);
 270         *list_read_count += newpacket->length;
 271
 272         if (*list_read_count > bytes_read) {
 273                 /* point to the start of unread data */
 274                 j = newpacket->length - (*list_read_count - bytes_read);
 275                 /* point to the offset in the packet buffer */
 276                 ptemp_buf = (u8 *) newpacket->data + j;
 277                 /*
 278                  * check if there is enough room in
 279                  * * the incoming buffer
 280                  */
 281                 if (length > (*list_read_count - bytes_read))
 282                         /*
 283                          * copy what ever is there in this
 284                          * packet and move on
 285                          */
 286                         bytes_copied = (*list_read_count - bytes_read);
 287                 else
 288                         /* copy the remaining */
 289                         bytes_copied = length;
 290                 memcpy(data, ptemp_buf, bytes_copied);
 291         }
 292         return bytes_copied;
 293 }
 294
 295 static int packet_read_list(char *data, size_t * pread_length)
 296 {
 297         struct list_head *ptemp_list;
 298         int temp_count = 0;
 299         int bytes_copied = 0;
 300         int bytes_read = 0;
 301         int remaining_bytes = 0;
 302         char *pdest = data;
 303
 304         /* check if we have any packets */
 305         if (0 == rbu_data.num_packets)
 306                 return -ENOMEM;
 307
 308         remaining_bytes = *pread_length;
 309         bytes_read = rbu_data.packet_read_count;
 310
 311         ptemp_list = (&packet_data_head.list)->next;
 312         while (!list_empty(ptemp_list)) {
 313                 bytes_copied = do_packet_read(pdest, ptemp_list,
 314                         remaining_bytes, bytes_read, &temp_count);
 315                 remaining_bytes -= bytes_copied;
 316                 bytes_read += bytes_copied;
 317                 pdest += bytes_copied;
 318                 /*
 319                  * check if we reached end of buffer before reaching the
 320                  * last packet
 321                  */
 322                 if (remaining_bytes == 0)
 323                         break;
 324
 325                 ptemp_list = ptemp_list->next;
 326         }
 327         /*finally set the bytes read */
 328         *pread_length = bytes_read - rbu_data.packet_read_count;
 329         rbu_data.packet_read_count = bytes_read;
 330         return 0;
 331 }
 332
 333 static void packet_empty_list(void)
 334 {
 335         struct list_head *ptemp_list;
 336         struct list_head *pnext_list;
 337         struct packet_data *newpacket;
 338
 339         ptemp_list = (&packet_data_head.list)->next;
 340         while (!list_empty(ptemp_list)) {
 341                 newpacket =
 342                         list_entry(ptemp_list, struct packet_data, list);
 343                 pnext_list = ptemp_list->next;
 344                 list_del(ptemp_list);
 345                 ptemp_list = pnext_list;
 346                 /*
 347                  * zero out the RBU packet memory before freeing
 348                  * to make sure there are no stale RBU packets left in memory
 349                  */
 350                 memset(newpacket->data, 0, rbu_data.packetsize);
 351                 free_pages((unsigned long) newpacket->data,
 352                         newpacket->ordernum);
 353                 kfree(newpacket);
 354         }
 355         rbu_data.packet_read_count = 0;
 356         rbu_data.num_packets = 0;
 357         rbu_data.imagesize = 0;
 358 }
 359
 360 /*
 361  * img_update_free: Frees the buffer allocated for storing BIOS image
 362  * Always called with lock held and returned with lock held
 363  */
 364 static void img_update_free(void)
 365 {
 366         if (!rbu_data.image_update_buffer)
 367                 return;
 368         /*
 369          * zero out this buffer before freeing it to get rid of any stale
 370          * BIOS image copied in memory.
 371          */
 372         memset(rbu_data.image_update_buffer, 0,
 373                 rbu_data.image_update_buffer_size);
 374         if (rbu_data.dma_alloc == 1)
 375                 dma_free_coherent(NULL, rbu_data.bios_image_size,
 376                         rbu_data.image_update_buffer, dell_rbu_dmaaddr);
 377         else
 378                 free_pages((unsigned long) rbu_data.image_update_buffer,
 379                         rbu_data.image_update_ordernum);
 380
 381         /*
 382          * Re-initialize the rbu_data variables after a free
 383          */
 384         rbu_data.image_update_ordernum = -1;
 385         rbu_data.image_update_buffer = NULL;
 386         rbu_data.image_update_buffer_size = 0;
 387         rbu_data.bios_image_size = 0;
 388         rbu_data.dma_alloc = 0;
 389 }
 390
 391 /*
 392  * img_update_realloc: This function allocates the contiguous pages to
 393  * accommodate the requested size of data. The memory address and size
 394  * values are stored globally and on every call to this function the new
 395  * size is checked to see if more data is required than the existing size.
 396  * If true the previous memory is freed and new allocation is done to
 397  * accommodate the new size. If the incoming size is less then than the
 398  * already allocated size, then that memory is reused. This function is
 399  * called with lock held and returns with lock held.
 400  */
 401 static int img_update_realloc(unsigned long size)
 402 {
 403         unsigned char *image_update_buffer = NULL;
 404         unsigned long rc;
 405         unsigned long img_buf_phys_addr;
 406         int ordernum;
 407         int dma_alloc = 0;
 408
 409         /*
 410          * check if the buffer of sufficient size has been
 411          * already allocated
 412          */
 413         if (rbu_data.image_update_buffer_size >= size) {
 414                 /*
 415                  * check for corruption
 416                  */
 417                 if ((size != 0) && (rbu_data.image_update_buffer == NULL)) {
 418                         printk(KERN_ERR "dell_rbu:%s: corruption "
 419                                 "check failed\n", __func__);
 420                         return -EINVAL;
 421                 }
 422                 /*
 423                  * we have a valid pre-allocated buffer with
 424                  * sufficient size
 425                  */
 426                 return 0;
 427         }
 428
 429         /*
 430          * free any previously allocated buffer
 431          */
 432         img_update_free();
 433
 434         spin_unlock(&rbu_data.lock);
 435
 436         ordernum = get_order(size);
 437         image_update_buffer =
 438                 (unsigned char *) __get_free_pages(GFP_KERNEL, ordernum);
 439
 440         img_buf_phys_addr =
 441                 (unsigned long) virt_to_phys(image_update_buffer);
 442
 443         if (img_buf_phys_addr > BIOS_SCAN_LIMIT) {
 444                 free_pages((unsigned long) image_update_buffer, ordernum);
 445                 ordernum = -1;
 446                 image_update_buffer = dma_alloc_coherent(NULL, size,
 447                         &dell_rbu_dmaaddr, GFP_KERNEL);
 448                 dma_alloc = 1;
 449         }
 450
 451         spin_lock(&rbu_data.lock);
 452
 453         if (image_update_buffer != NULL) {
 454                 rbu_data.image_update_buffer = image_update_buffer;
 455                 rbu_data.image_update_buffer_size = size;
 456                 rbu_data.bios_image_size =
 457                         rbu_data.image_update_buffer_size;
 458                 rbu_data.image_update_ordernum = ordernum;
 459                 rbu_data.dma_alloc = dma_alloc;
 460                 rc = 0;
 461         } else {
 462                 pr_debug("Not enough memory for image update:"
 463                         "size = %ld\n", size);
 464                 rc = -ENOMEM;
 465         }
 466
 467         return rc;
 468 }
 469
 470 static ssize_t read_packet_data(char *buffer, loff_t pos, size_t count)
 471 {
 472         int retval;
 473         size_t bytes_left;
 474         size_t data_length;
 475         char *ptempBuf = buffer;
 476
 477         /* check to see if we have something to return */
 478         if (rbu_data.num_packets == 0) {
 479                 pr_debug("read_packet_data: no packets written\n");
 480                 retval = -ENOMEM;
 481                 goto read_rbu_data_exit;
 482         }
 483
 484         if (pos > rbu_data.imagesize) {
 485                 retval = 0;
 486                 printk(KERN_WARNING "dell_rbu:read_packet_data: "
 487                         "data underrun\n");
 488                 goto read_rbu_data_exit;
 489         }
 490
 491         bytes_left = rbu_data.imagesize - pos;
 492         data_length = min(bytes_left, count);
 493
 494         if ((retval = packet_read_list(ptempBuf, &data_length)) < 0)
 495                 goto read_rbu_data_exit;
 496
 497         if ((pos + count) > rbu_data.imagesize) {
 498                 rbu_data.packet_read_count = 0;
 499                 /* this was the last copy */
 500                 retval = bytes_left;
 501         } else
 502                 retval = count;
 503
 504       read_rbu_data_exit:
 505         return retval;
 506 }
 507
 508 static ssize_t read_rbu_mono_data(char *buffer, loff_t pos, size_t count)
 509 {
 510         unsigned char *ptemp = NULL;
 511         size_t bytes_left = 0;
 512         size_t data_length = 0;
 513         ssize_t ret_count = 0;
 514
 515         /* check to see if we have something to return */
 516         if ((rbu_data.image_update_buffer == NULL) ||
 517                 (rbu_data.bios_image_size == 0)) {
 518                 pr_debug("read_rbu_data_mono: image_update_buffer %p ,"
 519                         "bios_image_size %lu\n",
 520                         rbu_data.image_update_buffer,
 521                         rbu_data.bios_image_size);
 522                 ret_count = -ENOMEM;
 523                 goto read_rbu_data_exit;
 524         }
 525
 526         if (pos > rbu_data.bios_image_size) {
 527                 ret_count = 0;
 528                 goto read_rbu_data_exit;
 529         }
 530
 531         bytes_left = rbu_data.bios_image_size - pos;
 532         data_length = min(bytes_left, count);
 533
 534         ptemp = rbu_data.image_update_buffer;
 535         memcpy(buffer, (ptemp + pos), data_length);
 536
 537         if ((pos + count) > rbu_data.bios_image_size)
 538                 /* this was the last copy */
 539                 ret_count = bytes_left;
 540         else
 541                 ret_count = count;
 542       read_rbu_data_exit:
 543         return ret_count;
 544 }
 545
 546 static ssize_t read_rbu_data(struct kobject *kobj,
 547                              struct bin_attribute *bin_attr,
 548                              char *buffer, loff_t pos, size_t count)
 549 {
 550         ssize_t ret_count = 0;
 551
 552         spin_lock(&rbu_data.lock);
 553
 554         if (!strcmp(image_type, "mono"))
 555                 ret_count = read_rbu_mono_data(buffer, pos, count);
 556         else if (!strcmp(image_type, "packet"))
 557                 ret_count = read_packet_data(buffer, pos, count);
 558         else
 559                 pr_debug("read_rbu_data: invalid image type specified\n");
 560
 561         spin_unlock(&rbu_data.lock);
 562         return ret_count;
 563 }
 564
 565 static void callbackfn_rbu(const struct firmware *fw, void *context)
 566 {
 567         rbu_data.entry_created = 0;
 568
 569         if (!fw || !fw->size)
 570                 return;
 571
 572         spin_lock(&rbu_data.lock);
 573         if (!strcmp(image_type, "mono")) {
 574                 if (!img_update_realloc(fw->size))
 575                         memcpy(rbu_data.image_update_buffer,
 576                                 fw->data, fw->size);
 577         } else if (!strcmp(image_type, "packet")) {
 578                 /*
 579                  * we need to free previous packets if a
 580                  * new hunk of packets needs to be downloaded
 581                  */
 582                 packet_empty_list();
 583                 if (packetize_data(fw->data, fw->size))
 584                         /* Incase something goes wrong when we are
 585                          * in middle of packetizing the data, we
 586                          * need to free up whatever packets might
 587                          * have been created before we quit.
 588                          */
 589                         packet_empty_list();
 590         } else
 591                 pr_debug("invalid image type specified.\n");
 592         spin_unlock(&rbu_data.lock);
 593 }
 594
 595 static ssize_t read_rbu_image_type(struct kobject *kobj,
 596                                    struct bin_attribute *bin_attr,
 597                                    char *buffer, loff_t pos, size_t count)
 598 {
 599         int size = 0;
 600         if (!pos)
 601                 size = sprintf(buffer, "%s\n", image_type);
 602         return size;
 603 }
 604
 605 static ssize_t write_rbu_image_type(struct kobject *kobj,
 606                                     struct bin_attribute *bin_attr,
 607                                     char *buffer, loff_t pos, size_t count)
 608 {
 609         int rc = count;
 610         int req_firm_rc = 0;
 611         int i;
 612         spin_lock(&rbu_data.lock);
 613         /*
 614          * Find the first newline or space
 615          */
 616         for (i = 0; i < count; ++i)
 617                 if (buffer[i] == '\n' || buffer[i] == ' ') {
 618                         buffer[i] = '\0';
 619                         break;
 620                 }
 621         if (i == count)
 622                 buffer[count] = '\0';
 623
 624         if (strstr(buffer, "mono"))
 625                 strcpy(image_type, "mono");
 626         else if (strstr(buffer, "packet"))
 627                 strcpy(image_type, "packet");
 628         else if (strstr(buffer, "init")) {
 629                 /*
 630                  * If due to the user error the driver gets in a bad
 631                  * state where even though it is loaded , the
 632                  * /sys/class/firmware/dell_rbu entries are missing.
 633                  * to cover this situation the user can recreate entries
 634                  * by writing init to image_type.
 635                  */
 636                 if (!rbu_data.entry_created) {
 637                         spin_unlock(&rbu_data.lock);
 638                         req_firm_rc = request_firmware_nowait(THIS_MODULE,
 639                                 FW_ACTION_NOHOTPLUG, "dell_rbu",
 640                                 &rbu_device->dev, &context,
 641                                 callbackfn_rbu);
 642                         if (req_firm_rc) {
 643                                 printk(KERN_ERR
 644                                         "dell_rbu:%s request_firmware_nowait"
 645                                         " failed %d\n", __func__, rc);
 646                                 rc = -EIO;
 647                         } else
 648                                 rbu_data.entry_created = 1;
 649
 650                         spin_lock(&rbu_data.lock);
 651                 }
 652         } else {
 653                 printk(KERN_WARNING "dell_rbu: image_type is invalid\n");
 654                 spin_unlock(&rbu_data.lock);
 655                 return -EINVAL;
 656         }
 657
 658         /* we must free all previous allocations */
 659         packet_empty_list();
 660         img_update_free();
 661         spin_unlock(&rbu_data.lock);
 662
 663         return rc;
 664 }
 665
 666 static ssize_t read_rbu_packet_size(struct kobject *kobj,
 667                                     struct bin_attribute *bin_attr,
 668                                     char *buffer, loff_t pos, size_t count)
 669 {
 670         int size = 0;
 671         if (!pos) {
 672                 spin_lock(&rbu_data.lock);
 673                 size = sprintf(buffer, "%lu\n", rbu_data.packetsize);
 674                 spin_unlock(&rbu_data.lock);
 675         }
 676         return size;
 677 }
 678
 679 static ssize_t write_rbu_packet_size(struct kobject *kobj,
 680                                      struct bin_attribute *bin_attr,
 681                                      char *buffer, loff_t pos, size_t count)
 682 {
 683         unsigned long temp;
 684         spin_lock(&rbu_data.lock);
 685         packet_empty_list();
 686         sscanf(buffer, "%lu", &temp);
 687         if (temp < 0xffffffff)
 688                 rbu_data.packetsize = temp;
 689
 690         spin_unlock(&rbu_data.lock);
 691         return count;
 692 }
 693
 694 static struct bin_attribute rbu_data_attr = {
 695         .attr = {.name = "data", .mode = 0444},
 696         .read = read_rbu_data,
 697 };
 698
 699 static struct bin_attribute rbu_image_type_attr = {
 700         .attr = {.name = "image_type", .mode = 0644},
 701         .read = read_rbu_image_type,
 702         .write = write_rbu_image_type,
 703 };
 704
 705 static struct bin_attribute rbu_packet_size_attr = {
 706         .attr = {.name = "packet_size", .mode = 0644},
 707         .read = read_rbu_packet_size,
 708         .write = write_rbu_packet_size,
 709 };
 710
 711 static int __init dcdrbu_init(void)
 712 {
 713         int rc;
 714         spin_lock_init(&rbu_data.lock);
 715
 716         init_packet_head();
 717         rbu_device = platform_device_register_simple("dell_rbu", -1, NULL, 0);
 718         if (IS_ERR(rbu_device)) {
 719                 printk(KERN_ERR
 720                         "dell_rbu:%s:platform_device_register_simple "
 721                         "failed\n", __func__);
 722                 return PTR_ERR(rbu_device);
 723         }
 724
 725         rc = sysfs_create_bin_file(&rbu_device->dev.kobj, &rbu_data_attr);
 726         if (rc)
 727                 goto out_devreg;
 728         rc = sysfs_create_bin_file(&rbu_device->dev.kobj, &rbu_image_type_attr);
 729         if (rc)
 730                 goto out_data;
 731         rc = sysfs_create_bin_file(&rbu_device->dev.kobj,
 732                 &rbu_packet_size_attr);
 733         if (rc)
 734                 goto out_imtype;
 735
 736         rbu_data.entry_created = 0;
 737         return 0;
 738
 739 out_imtype:
 740         sysfs_remove_bin_file(&rbu_device->dev.kobj, &rbu_image_type_attr);
 741 out_data:
 742         sysfs_remove_bin_file(&rbu_device->dev.kobj, &rbu_data_attr);
 743 out_devreg:
 744         platform_device_unregister(rbu_device);
 745         return rc;
 746 }
 747
 748 static __exit void dcdrbu_exit(void)
 749 {
 750         spin_lock(&rbu_data.lock);
 751         packet_empty_list();
 752         img_update_free();
 753         spin_unlock(&rbu_data.lock);
 754         platform_device_unregister(rbu_device);
 755 }
 756
 757 module_exit(dcdrbu_exit);
 758 module_init(dcdrbu_init);
 759
 760 /* vim:noet:ts=8:sw=8
 761 */