drivers/acpi/pfr_update.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ACPI Platform Firmware Runtime Update Device driver
   4  *
   5  * Copyright (C) 2021 Intel Corporation
   6  * Author: Chen Yu <yu.c.chen@intel.com>
   7  *
   8  * pfr_update driver is used for Platform Firmware Runtime
   9  * Update, which includes the code injection and driver update.
  10  */
  11 #include <linux/acpi.h>
  12 #include <linux/device.h>
  13 #include <linux/efi.h>
  14 #include <linux/err.h>
  15 #include <linux/errno.h>
  16 #include <linux/file.h>
  17 #include <linux/fs.h>
  18 #include <linux/idr.h>
  19 #include <linux/miscdevice.h>
  20 #include <linux/module.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/string.h>
  23 #include <linux/uaccess.h>
  24 #include <linux/uio.h>
  25 #include <linux/uuid.h>
  26
  27 #include <uapi/linux/pfrut.h>
  28
  29 #define PFRU_FUNC_STANDARD_QUERY        0
  30 #define PFRU_FUNC_QUERY_UPDATE_CAP      1
  31 #define PFRU_FUNC_QUERY_BUF             2
  32 #define PFRU_FUNC_START         3
  33
  34 #define PFRU_CODE_INJECT_TYPE   1
  35 #define PFRU_DRIVER_UPDATE_TYPE 2
  36
  37 #define PFRU_REVID_1            1
  38 #define PFRU_REVID_2            2
  39 #define PFRU_DEFAULT_REV_ID     PFRU_REVID_1
  40
  41 enum cap_index {
  42         CAP_STATUS_IDX = 0,
  43         CAP_UPDATE_IDX = 1,
  44         CAP_CODE_TYPE_IDX = 2,
  45         CAP_FW_VER_IDX = 3,
  46         CAP_CODE_RT_VER_IDX = 4,
  47         CAP_DRV_TYPE_IDX = 5,
  48         CAP_DRV_RT_VER_IDX = 6,
  49         CAP_DRV_SVN_IDX = 7,
  50         CAP_PLAT_ID_IDX = 8,
  51         CAP_OEM_ID_IDX = 9,
  52         CAP_OEM_INFO_IDX = 10,
  53         CAP_NR_IDX
  54 };
  55
  56 enum buf_index {
  57         BUF_STATUS_IDX = 0,
  58         BUF_EXT_STATUS_IDX = 1,
  59         BUF_ADDR_LOW_IDX = 2,
  60         BUF_ADDR_HI_IDX = 3,
  61         BUF_SIZE_IDX = 4,
  62         BUF_NR_IDX
  63 };
  64
  65 enum update_index {
  66         UPDATE_STATUS_IDX = 0,
  67         UPDATE_EXT_STATUS_IDX = 1,
  68         UPDATE_AUTH_TIME_LOW_IDX = 2,
  69         UPDATE_AUTH_TIME_HI_IDX = 3,
  70         UPDATE_EXEC_TIME_LOW_IDX = 4,
  71         UPDATE_EXEC_TIME_HI_IDX = 5,
  72         UPDATE_NR_IDX
  73 };
  74
  75 enum pfru_start_action {
  76         START_STAGE = 0,
  77         START_ACTIVATE = 1,
  78         START_STAGE_ACTIVATE = 2,
  79 };
  80
  81 struct pfru_device {
  82         u32 rev_id, index;
  83         struct device *parent_dev;
  84         struct miscdevice miscdev;
  85 };
  86
  87 static DEFINE_IDA(pfru_ida);
  88
  89 /*
  90  * Manual reference:
  91  * https://uefi.org/sites/default/files/resources/Intel_MM_OS_Interface_Spec_Rev100.pdf
  92  *
  93  * pfru_guid is the parameter for _DSM method
  94  */
  95 static const guid_t pfru_guid =
  96         GUID_INIT(0xECF9533B, 0x4A3C, 0x4E89, 0x93, 0x9E, 0xC7, 0x71,
  97                   0x12, 0x60, 0x1C, 0x6D);
  98
  99 /* pfru_code_inj_guid is the UUID to identify code injection EFI capsule file */
 100 static const guid_t pfru_code_inj_guid =
 101         GUID_INIT(0xB2F84B79, 0x7B6E, 0x4E45, 0x88, 0x5F, 0x3F, 0xB9,
 102                   0xBB, 0x18, 0x54, 0x02);
 103
 104 /* pfru_drv_update_guid is the UUID to identify driver update EFI capsule file */
 105 static const guid_t pfru_drv_update_guid =
 106         GUID_INIT(0x4569DD8C, 0x75F1, 0x429A, 0xA3, 0xD6, 0x24, 0xDE,
 107                   0x80, 0x97, 0xA0, 0xDF);
 108
 109 static inline int pfru_valid_revid(u32 id)
 110 {
 111         return id == PFRU_REVID_1 || id == PFRU_REVID_2;
 112 }
 113
 114 static inline struct pfru_device *to_pfru_dev(struct file *file)
 115 {
 116         return container_of(file->private_data, struct pfru_device, miscdev);
 117 }
 118
 119 static int query_capability(struct pfru_update_cap_info *cap_hdr,
 120                             struct pfru_device *pfru_dev)
 121 {
 122         acpi_handle handle = ACPI_HANDLE(pfru_dev->parent_dev);
 123         union acpi_object *out_obj;
 124         int ret = -EINVAL;
 125
 126         out_obj = acpi_evaluate_dsm_typed(handle, &pfru_guid,
 127                                           pfru_dev->rev_id,
 128                                           PFRU_FUNC_QUERY_UPDATE_CAP,
 129                                           NULL, ACPI_TYPE_PACKAGE);
 130         if (!out_obj)
 131                 return ret;
 132
 133         if (out_obj->package.count < CAP_NR_IDX ||
 134             out_obj->package.elements[CAP_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
 135             out_obj->package.elements[CAP_UPDATE_IDX].type != ACPI_TYPE_INTEGER ||
 136             out_obj->package.elements[CAP_CODE_TYPE_IDX].type != ACPI_TYPE_BUFFER ||
 137             out_obj->package.elements[CAP_FW_VER_IDX].type != ACPI_TYPE_INTEGER ||
 138             out_obj->package.elements[CAP_CODE_RT_VER_IDX].type != ACPI_TYPE_INTEGER ||
 139             out_obj->package.elements[CAP_DRV_TYPE_IDX].type != ACPI_TYPE_BUFFER ||
 140             out_obj->package.elements[CAP_DRV_RT_VER_IDX].type != ACPI_TYPE_INTEGER ||
 141             out_obj->package.elements[CAP_DRV_SVN_IDX].type != ACPI_TYPE_INTEGER ||
 142             out_obj->package.elements[CAP_PLAT_ID_IDX].type != ACPI_TYPE_BUFFER ||
 143             out_obj->package.elements[CAP_OEM_ID_IDX].type != ACPI_TYPE_BUFFER ||
 144             out_obj->package.elements[CAP_OEM_INFO_IDX].type != ACPI_TYPE_BUFFER)
 145                 goto free_acpi_buffer;
 146
 147         cap_hdr->status = out_obj->package.elements[CAP_STATUS_IDX].integer.value;
 148         if (cap_hdr->status != DSM_SUCCEED) {
 149                 ret = -EBUSY;
 150                 dev_dbg(pfru_dev->parent_dev, "Error Status:%d\n", cap_hdr->status);
 151                 goto free_acpi_buffer;
 152         }
 153
 154         cap_hdr->update_cap = out_obj->package.elements[CAP_UPDATE_IDX].integer.value;
 155         memcpy(&cap_hdr->code_type,
 156                out_obj->package.elements[CAP_CODE_TYPE_IDX].buffer.pointer,
 157                out_obj->package.elements[CAP_CODE_TYPE_IDX].buffer.length);
 158         cap_hdr->fw_version =
 159                 out_obj->package.elements[CAP_FW_VER_IDX].integer.value;
 160         cap_hdr->code_rt_version =
 161                 out_obj->package.elements[CAP_CODE_RT_VER_IDX].integer.value;
 162         memcpy(&cap_hdr->drv_type,
 163                out_obj->package.elements[CAP_DRV_TYPE_IDX].buffer.pointer,
 164                out_obj->package.elements[CAP_DRV_TYPE_IDX].buffer.length);
 165         cap_hdr->drv_rt_version =
 166                 out_obj->package.elements[CAP_DRV_RT_VER_IDX].integer.value;
 167         cap_hdr->drv_svn =
 168                 out_obj->package.elements[CAP_DRV_SVN_IDX].integer.value;
 169         memcpy(&cap_hdr->platform_id,
 170                out_obj->package.elements[CAP_PLAT_ID_IDX].buffer.pointer,
 171                out_obj->package.elements[CAP_PLAT_ID_IDX].buffer.length);
 172         memcpy(&cap_hdr->oem_id,
 173                out_obj->package.elements[CAP_OEM_ID_IDX].buffer.pointer,
 174                out_obj->package.elements[CAP_OEM_ID_IDX].buffer.length);
 175         cap_hdr->oem_info_len =
 176                 out_obj->package.elements[CAP_OEM_INFO_IDX].buffer.length;
 177
 178         ret = 0;
 179
 180 free_acpi_buffer:
 181         ACPI_FREE(out_obj);
 182
 183         return ret;
 184 }
 185
 186 static int query_buffer(struct pfru_com_buf_info *info,
 187                         struct pfru_device *pfru_dev)
 188 {
 189         acpi_handle handle = ACPI_HANDLE(pfru_dev->parent_dev);
 190         union acpi_object *out_obj;
 191         int ret = -EINVAL;
 192
 193         out_obj = acpi_evaluate_dsm_typed(handle, &pfru_guid,
 194                                           pfru_dev->rev_id, PFRU_FUNC_QUERY_BUF,
 195                                           NULL, ACPI_TYPE_PACKAGE);
 196         if (!out_obj)
 197                 return ret;
 198
 199         if (out_obj->package.count < BUF_NR_IDX ||
 200             out_obj->package.elements[BUF_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
 201             out_obj->package.elements[BUF_EXT_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
 202             out_obj->package.elements[BUF_ADDR_LOW_IDX].type != ACPI_TYPE_INTEGER ||
 203             out_obj->package.elements[BUF_ADDR_HI_IDX].type != ACPI_TYPE_INTEGER ||
 204             out_obj->package.elements[BUF_SIZE_IDX].type != ACPI_TYPE_INTEGER)
 205                 goto free_acpi_buffer;
 206
 207         info->status = out_obj->package.elements[BUF_STATUS_IDX].integer.value;
 208         info->ext_status =
 209                 out_obj->package.elements[BUF_EXT_STATUS_IDX].integer.value;
 210         if (info->status != DSM_SUCCEED) {
 211                 ret = -EBUSY;
 212                 dev_dbg(pfru_dev->parent_dev, "Error Status:%d\n", info->status);
 213                 dev_dbg(pfru_dev->parent_dev, "Error Extended Status:%d\n", info->ext_status);
 214
 215                 goto free_acpi_buffer;
 216         }
 217
 218         info->addr_lo =
 219                 out_obj->package.elements[BUF_ADDR_LOW_IDX].integer.value;
 220         info->addr_hi =
 221                 out_obj->package.elements[BUF_ADDR_HI_IDX].integer.value;
 222         info->buf_size = out_obj->package.elements[BUF_SIZE_IDX].integer.value;
 223
 224         ret = 0;
 225
 226 free_acpi_buffer:
 227         ACPI_FREE(out_obj);
 228
 229         return ret;
 230 }
 231
 232 static int get_image_type(const struct efi_manage_capsule_image_header *img_hdr,
 233                           struct pfru_device *pfru_dev)
 234 {
 235         const efi_guid_t *image_type_id = &img_hdr->image_type_id;
 236
 237         /* check whether this is a code injection or driver update */
 238         if (guid_equal(image_type_id, &pfru_code_inj_guid))
 239                 return PFRU_CODE_INJECT_TYPE;
 240
 241         if (guid_equal(image_type_id, &pfru_drv_update_guid))
 242                 return PFRU_DRIVER_UPDATE_TYPE;
 243
 244         return -EINVAL;
 245 }
 246
 247 static int adjust_efi_size(const struct efi_manage_capsule_image_header *img_hdr,
 248                            int size)
 249 {
 250         /*
 251          * The (u64 hw_ins) was introduced in UEFI spec version 2,
 252          * and (u64 capsule_support) was introduced in version 3.
 253          * The size needs to be adjusted accordingly. That is to
 254          * say, version 1 should subtract the size of hw_ins+capsule_support,
 255          * and version 2 should sbstract the size of capsule_support.
 256          */
 257         size += sizeof(struct efi_manage_capsule_image_header);
 258         switch (img_hdr->ver) {
 259         case 1:
 260                 return size - 2 * sizeof(u64);
 261
 262         case 2:
 263                 return size - sizeof(u64);
 264
 265         default:
 266                 /* only support version 1 and 2 */
 267                 return -EINVAL;
 268         }
 269 }
 270
 271 static bool applicable_image(const void *data, struct pfru_update_cap_info *cap,
 272                              struct pfru_device *pfru_dev)
 273 {
 274         struct pfru_payload_hdr *payload_hdr;
 275         const efi_capsule_header_t *cap_hdr = data;
 276         const struct efi_manage_capsule_header *m_hdr;
 277         const struct efi_manage_capsule_image_header *m_img_hdr;
 278         const struct efi_image_auth *auth;
 279         int type, size;
 280
 281         /*
 282          * If the code in the capsule is older than the current
 283          * firmware code, the update will be rejected by the firmware,
 284          * so check the version of it upfront without engaging the
 285          * Management Mode update mechanism which may be costly.
 286          */
 287         size = cap_hdr->headersize;
 288         m_hdr = data + size;
 289         /*
 290          * Current data structure size plus variable array indicated
 291          * by number of (emb_drv_cnt + payload_cnt)
 292          */
 293         size += offsetof(struct efi_manage_capsule_header, offset_list) +
 294                 (m_hdr->emb_drv_cnt + m_hdr->payload_cnt) * sizeof(u64);
 295         m_img_hdr = data + size;
 296
 297         type = get_image_type(m_img_hdr, pfru_dev);
 298         if (type < 0)
 299                 return false;
 300
 301         size = adjust_efi_size(m_img_hdr, size);
 302         if (size < 0)
 303                 return false;
 304
 305         auth = data + size;
 306         size += sizeof(u64) + auth->auth_info.hdr.len;
 307         payload_hdr = (struct pfru_payload_hdr *)(data + size);
 308
 309         /* finally compare the version */
 310         if (type == PFRU_CODE_INJECT_TYPE)
 311                 return payload_hdr->rt_ver >= cap->code_rt_version;
 312
 313         return payload_hdr->rt_ver >= cap->drv_rt_version;
 314 }
 315
 316 static void print_update_debug_info(struct pfru_updated_result *result,
 317                                     struct pfru_device *pfru_dev)
 318 {
 319         dev_dbg(pfru_dev->parent_dev, "Update result:\n");
 320         dev_dbg(pfru_dev->parent_dev, "Authentication Time Low:%lld\n",
 321                 result->low_auth_time);
 322         dev_dbg(pfru_dev->parent_dev, "Authentication Time High:%lld\n",
 323                 result->high_auth_time);
 324         dev_dbg(pfru_dev->parent_dev, "Execution Time Low:%lld\n",
 325                 result->low_exec_time);
 326         dev_dbg(pfru_dev->parent_dev, "Execution Time High:%lld\n",
 327                 result->high_exec_time);
 328 }
 329
 330 static int start_update(int action, struct pfru_device *pfru_dev)
 331 {
 332         union acpi_object *out_obj, in_obj, in_buf;
 333         struct pfru_updated_result update_result;
 334         acpi_handle handle;
 335         int ret = -EINVAL;
 336
 337         memset(&in_obj, 0, sizeof(in_obj));
 338         memset(&in_buf, 0, sizeof(in_buf));
 339         in_obj.type = ACPI_TYPE_PACKAGE;
 340         in_obj.package.count = 1;
 341         in_obj.package.elements = &in_buf;
 342         in_buf.type = ACPI_TYPE_INTEGER;
 343         in_buf.integer.value = action;
 344
 345         handle = ACPI_HANDLE(pfru_dev->parent_dev);
 346         out_obj = acpi_evaluate_dsm_typed(handle, &pfru_guid,
 347                                           pfru_dev->rev_id, PFRU_FUNC_START,
 348                                           &in_obj, ACPI_TYPE_PACKAGE);
 349         if (!out_obj)
 350                 return ret;
 351
 352         if (out_obj->package.count < UPDATE_NR_IDX ||
 353             out_obj->package.elements[UPDATE_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
 354             out_obj->package.elements[UPDATE_EXT_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
 355             out_obj->package.elements[UPDATE_AUTH_TIME_LOW_IDX].type != ACPI_TYPE_INTEGER ||
 356             out_obj->package.elements[UPDATE_AUTH_TIME_HI_IDX].type != ACPI_TYPE_INTEGER ||
 357             out_obj->package.elements[UPDATE_EXEC_TIME_LOW_IDX].type != ACPI_TYPE_INTEGER ||
 358             out_obj->package.elements[UPDATE_EXEC_TIME_HI_IDX].type != ACPI_TYPE_INTEGER)
 359                 goto free_acpi_buffer;
 360
 361         update_result.status =
 362                 out_obj->package.elements[UPDATE_STATUS_IDX].integer.value;
 363         update_result.ext_status =
 364                 out_obj->package.elements[UPDATE_EXT_STATUS_IDX].integer.value;
 365
 366         if (update_result.status != DSM_SUCCEED) {
 367                 ret = -EBUSY;
 368                 dev_dbg(pfru_dev->parent_dev, "Error Status:%d\n", update_result.status);
 369                 dev_dbg(pfru_dev->parent_dev, "Error Extended Status:%d\n",
 370                         update_result.ext_status);
 371
 372                 goto free_acpi_buffer;
 373         }
 374
 375         update_result.low_auth_time =
 376                 out_obj->package.elements[UPDATE_AUTH_TIME_LOW_IDX].integer.value;
 377         update_result.high_auth_time =
 378                 out_obj->package.elements[UPDATE_AUTH_TIME_HI_IDX].integer.value;
 379         update_result.low_exec_time =
 380                 out_obj->package.elements[UPDATE_EXEC_TIME_LOW_IDX].integer.value;
 381         update_result.high_exec_time =
 382                 out_obj->package.elements[UPDATE_EXEC_TIME_HI_IDX].integer.value;
 383
 384         print_update_debug_info(&update_result, pfru_dev);
 385         ret = 0;
 386
 387 free_acpi_buffer:
 388         ACPI_FREE(out_obj);
 389
 390         return ret;
 391 }
 392
 393 static long pfru_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 394 {
 395         struct pfru_update_cap_info cap_hdr;
 396         struct pfru_device *pfru_dev = to_pfru_dev(file);
 397         void __user *p = (void __user *)arg;
 398         u32 rev;
 399         int ret;
 400
 401         switch (cmd) {
 402         case PFRU_IOC_QUERY_CAP:
 403                 ret = query_capability(&cap_hdr, pfru_dev);
 404                 if (ret)
 405                         return ret;
 406
 407                 if (copy_to_user(p, &cap_hdr, sizeof(cap_hdr)))
 408                         return -EFAULT;
 409
 410                 return 0;
 411
 412         case PFRU_IOC_SET_REV:
 413                 if (copy_from_user(&rev, p, sizeof(rev)))
 414                         return -EFAULT;
 415
 416                 if (!pfru_valid_revid(rev))
 417                         return -EINVAL;
 418
 419                 pfru_dev->rev_id = rev;
 420
 421                 return 0;
 422
 423         case PFRU_IOC_STAGE:
 424                 return start_update(START_STAGE, pfru_dev);
 425
 426         case PFRU_IOC_ACTIVATE:
 427                 return start_update(START_ACTIVATE, pfru_dev);
 428
 429         case PFRU_IOC_STAGE_ACTIVATE:
 430                 return start_update(START_STAGE_ACTIVATE, pfru_dev);
 431
 432         default:
 433                 return -ENOTTY;
 434         }
 435 }
 436
 437 static ssize_t pfru_write(struct file *file, const char __user *buf,
 438                           size_t len, loff_t *ppos)
 439 {
 440         struct pfru_device *pfru_dev = to_pfru_dev(file);
 441         struct pfru_update_cap_info cap;
 442         struct pfru_com_buf_info buf_info;
 443         phys_addr_t phy_addr;
 444         struct iov_iter iter;
 445         struct iovec iov;
 446         char *buf_ptr;
 447         int ret;
 448
 449         ret = query_buffer(&buf_info, pfru_dev);
 450         if (ret)
 451                 return ret;
 452
 453         if (len > buf_info.buf_size)
 454                 return -EINVAL;
 455
 456         iov.iov_base = (void __user *)buf;
 457         iov.iov_len = len;
 458         iov_iter_init(&iter, ITER_SOURCE, &iov, 1, len);
 459
 460         /* map the communication buffer */
 461         phy_addr = (phys_addr_t)((buf_info.addr_hi << 32) | buf_info.addr_lo);
 462         buf_ptr = memremap(phy_addr, buf_info.buf_size, MEMREMAP_WB);
 463         if (!buf_ptr)
 464                 return -ENOMEM;
 465
 466         if (!copy_from_iter_full(buf_ptr, len, &iter)) {
 467                 ret = -EINVAL;
 468                 goto unmap;
 469         }
 470
 471         /* check if the capsule header has a valid version number */
 472         ret = query_capability(&cap, pfru_dev);
 473         if (ret)
 474                 goto unmap;
 475
 476         if (!applicable_image(buf_ptr, &cap, pfru_dev))
 477                 ret = -EINVAL;
 478
 479 unmap:
 480         memunmap(buf_ptr);
 481
 482         return ret ?: len;
 483 }
 484
 485 static const struct file_operations acpi_pfru_fops = {
 486         .owner          = THIS_MODULE,
 487         .write          = pfru_write,
 488         .unlocked_ioctl = pfru_ioctl,
 489         .llseek         = noop_llseek,
 490 };
 491
 492 static int acpi_pfru_remove(struct platform_device *pdev)
 493 {
 494         struct pfru_device *pfru_dev = platform_get_drvdata(pdev);
 495
 496         misc_deregister(&pfru_dev->miscdev);
 497
 498         return 0;
 499 }
 500
 501 static void pfru_put_idx(void *data)
 502 {
 503         struct pfru_device *pfru_dev = data;
 504
 505         ida_free(&pfru_ida, pfru_dev->index);
 506 }
 507
 508 static int acpi_pfru_probe(struct platform_device *pdev)
 509 {
 510         acpi_handle handle = ACPI_HANDLE(&pdev->dev);
 511         struct pfru_device *pfru_dev;
 512         int ret;
 513
 514         if (!acpi_has_method(handle, "_DSM")) {
 515                 dev_dbg(&pdev->dev, "Missing _DSM\n");
 516                 return -ENODEV;
 517         }
 518
 519         pfru_dev = devm_kzalloc(&pdev->dev, sizeof(*pfru_dev), GFP_KERNEL);
 520         if (!pfru_dev)
 521                 return -ENOMEM;
 522
 523         ret = ida_alloc(&pfru_ida, GFP_KERNEL);
 524         if (ret < 0)
 525                 return ret;
 526
 527         pfru_dev->index = ret;
 528         ret = devm_add_action_or_reset(&pdev->dev, pfru_put_idx, pfru_dev);
 529         if (ret)
 530                 return ret;
 531
 532         pfru_dev->rev_id = PFRU_DEFAULT_REV_ID;
 533         pfru_dev->parent_dev = &pdev->dev;
 534
 535         pfru_dev->miscdev.minor = MISC_DYNAMIC_MINOR;
 536         pfru_dev->miscdev.name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
 537                                                 "pfru%d", pfru_dev->index);
 538         if (!pfru_dev->miscdev.name)
 539                 return -ENOMEM;
 540
 541         pfru_dev->miscdev.nodename = devm_kasprintf(&pdev->dev, GFP_KERNEL,
 542                                                     "acpi_pfr_update%d", pfru_dev->index);
 543         if (!pfru_dev->miscdev.nodename)
 544                 return -ENOMEM;
 545
 546         pfru_dev->miscdev.fops = &acpi_pfru_fops;
 547         pfru_dev->miscdev.parent = &pdev->dev;
 548
 549         ret = misc_register(&pfru_dev->miscdev);
 550         if (ret)
 551                 return ret;
 552
 553         platform_set_drvdata(pdev, pfru_dev);
 554
 555         return 0;
 556 }
 557
 558 static const struct acpi_device_id acpi_pfru_ids[] = {
 559         {"INTC1080"},
 560         {}
 561 };
 562 MODULE_DEVICE_TABLE(acpi, acpi_pfru_ids);
 563
 564 static struct platform_driver acpi_pfru_driver = {
 565         .driver = {
 566                 .name = "pfr_update",
 567                 .acpi_match_table = acpi_pfru_ids,
 568         },
 569         .probe = acpi_pfru_probe,
 570         .remove = acpi_pfru_remove,
 571 };
 572 module_platform_driver(acpi_pfru_driver);
 573
 574 MODULE_DESCRIPTION("Platform Firmware Runtime Update device driver");
 575 MODULE_LICENSE("GPL v2");