1 /* 2 * 3 * Intel Management Engine Interface (Intel MEI) Linux driver 4 * Copyright (c) 2003-2012, Intel Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms and conditions of the GNU General Public License, 8 * version 2, as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 * 15 */ 16 #include <linux/module.h> 17 #include <linux/moduleparam.h> 18 #include <linux/kernel.h> 19 #include <linux/device.h> 20 #include <linux/slab.h> 21 #include <linux/fs.h> 22 #include <linux/errno.h> 23 #include <linux/types.h> 24 #include <linux/fcntl.h> 25 #include <linux/poll.h> 26 #include <linux/init.h> 27 #include <linux/ioctl.h> 28 #include <linux/cdev.h> 29 #include <linux/sched.h> 30 #include <linux/uuid.h> 31 #include <linux/compat.h> 32 #include <linux/jiffies.h> 33 #include <linux/interrupt.h> 34 35 #include <linux/mei.h> 36 37 #include "mei_dev.h" 38 #include "client.h" 39 40 /** 41 * mei_open - the open function 42 * 43 * @inode: pointer to inode structure 44 * @file: pointer to file structure 45 * 46 * Return: 0 on success, <0 on error 47 */ 48 static int mei_open(struct inode *inode, struct file *file) 49 { 50 struct mei_device *dev; 51 struct mei_cl *cl; 52 53 int err; 54 55 dev = container_of(inode->i_cdev, struct mei_device, cdev); 56 if (!dev) 57 return -ENODEV; 58 59 mutex_lock(&dev->device_lock); 60 61 if (dev->dev_state != MEI_DEV_ENABLED) { 62 dev_dbg(dev->dev, "dev_state != MEI_ENABLED dev_state = %s\n", 63 mei_dev_state_str(dev->dev_state)); 64 err = -ENODEV; 65 goto err_unlock; 66 } 67 68 cl = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY); 69 if (IS_ERR(cl)) { 70 err = PTR_ERR(cl); 71 goto err_unlock; 72 } 73 74 file->private_data = cl; 75 76 mutex_unlock(&dev->device_lock); 77 78 return nonseekable_open(inode, file); 79 80 err_unlock: 81 mutex_unlock(&dev->device_lock); 82 return err; 83 } 84 85 /** 86 * mei_release - the release function 87 * 88 * @inode: pointer to inode structure 89 * @file: pointer to file structure 90 * 91 * Return: 0 on success, <0 on error 92 */ 93 static int mei_release(struct inode *inode, struct file *file) 94 { 95 struct mei_cl *cl = file->private_data; 96 struct mei_device *dev; 97 int rets; 98 99 if (WARN_ON(!cl || !cl->dev)) 100 return -ENODEV; 101 102 dev = cl->dev; 103 104 mutex_lock(&dev->device_lock); 105 if (cl == &dev->iamthif_cl) { 106 rets = mei_amthif_release(dev, file); 107 goto out; 108 } 109 rets = mei_cl_disconnect(cl); 110 111 mei_cl_flush_queues(cl, file); 112 cl_dbg(dev, cl, "removing\n"); 113 114 mei_cl_unlink(cl); 115 116 file->private_data = NULL; 117 118 kfree(cl); 119 out: 120 mutex_unlock(&dev->device_lock); 121 return rets; 122 } 123 124 125 /** 126 * mei_read - the read function. 127 * 128 * @file: pointer to file structure 129 * @ubuf: pointer to user buffer 130 * @length: buffer length 131 * @offset: data offset in buffer 132 * 133 * Return: >=0 data length on success , <0 on error 134 */ 135 static ssize_t mei_read(struct file *file, char __user *ubuf, 136 size_t length, loff_t *offset) 137 { 138 struct mei_cl *cl = file->private_data; 139 struct mei_device *dev; 140 struct mei_cl_cb *cb = NULL; 141 int rets; 142 int err; 143 144 145 if (WARN_ON(!cl || !cl->dev)) 146 return -ENODEV; 147 148 dev = cl->dev; 149 150 151 mutex_lock(&dev->device_lock); 152 if (dev->dev_state != MEI_DEV_ENABLED) { 153 rets = -ENODEV; 154 goto out; 155 } 156 157 if (length == 0) { 158 rets = 0; 159 goto out; 160 } 161 162 if (cl == &dev->iamthif_cl) { 163 rets = mei_amthif_read(dev, file, ubuf, length, offset); 164 goto out; 165 } 166 167 cb = mei_cl_read_cb(cl, file); 168 if (cb) { 169 /* read what left */ 170 if (cb->buf_idx > *offset) 171 goto copy_buffer; 172 /* offset is beyond buf_idx we have no more data return 0 */ 173 if (cb->buf_idx > 0 && cb->buf_idx <= *offset) { 174 rets = 0; 175 goto free; 176 } 177 /* Offset needs to be cleaned for contiguous reads*/ 178 if (cb->buf_idx == 0 && *offset > 0) 179 *offset = 0; 180 } else if (*offset > 0) { 181 *offset = 0; 182 } 183 184 err = mei_cl_read_start(cl, length, file); 185 if (err && err != -EBUSY) { 186 cl_dbg(dev, cl, "mei start read failure status = %d\n", err); 187 rets = err; 188 goto out; 189 } 190 191 if (list_empty(&cl->rd_completed) && !waitqueue_active(&cl->rx_wait)) { 192 if (file->f_flags & O_NONBLOCK) { 193 rets = -EAGAIN; 194 goto out; 195 } 196 197 mutex_unlock(&dev->device_lock); 198 199 if (wait_event_interruptible(cl->rx_wait, 200 (!list_empty(&cl->rd_completed)) || 201 (!mei_cl_is_connected(cl)))) { 202 203 if (signal_pending(current)) 204 return -EINTR; 205 return -ERESTARTSYS; 206 } 207 208 mutex_lock(&dev->device_lock); 209 if (!mei_cl_is_connected(cl)) { 210 rets = -EBUSY; 211 goto out; 212 } 213 } 214 215 cb = mei_cl_read_cb(cl, file); 216 if (!cb) { 217 if (mei_cl_is_fixed_address(cl) && dev->allow_fixed_address) { 218 cb = mei_cl_read_cb(cl, NULL); 219 if (cb) 220 goto copy_buffer; 221 } 222 rets = 0; 223 goto out; 224 } 225 226 copy_buffer: 227 /* now copy the data to user space */ 228 if (cb->status) { 229 rets = cb->status; 230 cl_dbg(dev, cl, "read operation failed %d\n", rets); 231 goto free; 232 } 233 234 cl_dbg(dev, cl, "buf.size = %d buf.idx = %ld\n", 235 cb->buf.size, cb->buf_idx); 236 if (length == 0 || ubuf == NULL || *offset > cb->buf_idx) { 237 rets = -EMSGSIZE; 238 goto free; 239 } 240 241 /* length is being truncated to PAGE_SIZE, 242 * however buf_idx may point beyond that */ 243 length = min_t(size_t, length, cb->buf_idx - *offset); 244 245 if (copy_to_user(ubuf, cb->buf.data + *offset, length)) { 246 dev_dbg(dev->dev, "failed to copy data to userland\n"); 247 rets = -EFAULT; 248 goto free; 249 } 250 251 rets = length; 252 *offset += length; 253 if ((unsigned long)*offset < cb->buf_idx) 254 goto out; 255 256 free: 257 mei_io_cb_free(cb); 258 259 out: 260 cl_dbg(dev, cl, "end mei read rets = %d\n", rets); 261 mutex_unlock(&dev->device_lock); 262 return rets; 263 } 264 /** 265 * mei_write - the write function. 266 * 267 * @file: pointer to file structure 268 * @ubuf: pointer to user buffer 269 * @length: buffer length 270 * @offset: data offset in buffer 271 * 272 * Return: >=0 data length on success , <0 on error 273 */ 274 static ssize_t mei_write(struct file *file, const char __user *ubuf, 275 size_t length, loff_t *offset) 276 { 277 struct mei_cl *cl = file->private_data; 278 struct mei_cl_cb *write_cb = NULL; 279 struct mei_device *dev; 280 unsigned long timeout = 0; 281 int rets; 282 283 if (WARN_ON(!cl || !cl->dev)) 284 return -ENODEV; 285 286 dev = cl->dev; 287 288 mutex_lock(&dev->device_lock); 289 290 if (dev->dev_state != MEI_DEV_ENABLED) { 291 rets = -ENODEV; 292 goto out; 293 } 294 295 if (!mei_cl_is_connected(cl)) { 296 cl_err(dev, cl, "is not connected"); 297 rets = -ENODEV; 298 goto out; 299 } 300 301 if (!mei_me_cl_is_active(cl->me_cl)) { 302 rets = -ENOTTY; 303 goto out; 304 } 305 306 if (length > mei_cl_mtu(cl)) { 307 rets = -EFBIG; 308 goto out; 309 } 310 311 if (length == 0) { 312 rets = 0; 313 goto out; 314 } 315 316 if (cl == &dev->iamthif_cl) { 317 write_cb = mei_amthif_find_read_list_entry(dev, file); 318 319 if (write_cb) { 320 timeout = write_cb->read_time + 321 mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER); 322 323 if (time_after(jiffies, timeout)) { 324 *offset = 0; 325 mei_io_cb_free(write_cb); 326 write_cb = NULL; 327 } 328 } 329 } 330 331 *offset = 0; 332 write_cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file); 333 if (!write_cb) { 334 rets = -ENOMEM; 335 goto out; 336 } 337 338 rets = copy_from_user(write_cb->buf.data, ubuf, length); 339 if (rets) { 340 dev_dbg(dev->dev, "failed to copy data from userland\n"); 341 rets = -EFAULT; 342 goto out; 343 } 344 345 if (cl == &dev->iamthif_cl) { 346 rets = mei_amthif_write(cl, write_cb); 347 348 if (rets) { 349 dev_err(dev->dev, 350 "amthif write failed with status = %d\n", rets); 351 goto out; 352 } 353 mutex_unlock(&dev->device_lock); 354 return length; 355 } 356 357 rets = mei_cl_write(cl, write_cb, false); 358 out: 359 mutex_unlock(&dev->device_lock); 360 if (rets < 0) 361 mei_io_cb_free(write_cb); 362 return rets; 363 } 364 365 /** 366 * mei_ioctl_connect_client - the connect to fw client IOCTL function 367 * 368 * @file: private data of the file object 369 * @data: IOCTL connect data, input and output parameters 370 * 371 * Locking: called under "dev->device_lock" lock 372 * 373 * Return: 0 on success, <0 on failure. 374 */ 375 static int mei_ioctl_connect_client(struct file *file, 376 struct mei_connect_client_data *data) 377 { 378 struct mei_device *dev; 379 struct mei_client *client; 380 struct mei_me_client *me_cl; 381 struct mei_cl *cl; 382 int rets; 383 384 cl = file->private_data; 385 dev = cl->dev; 386 387 if (dev->dev_state != MEI_DEV_ENABLED) 388 return -ENODEV; 389 390 if (cl->state != MEI_FILE_INITIALIZING && 391 cl->state != MEI_FILE_DISCONNECTED) 392 return -EBUSY; 393 394 /* find ME client we're trying to connect to */ 395 me_cl = mei_me_cl_by_uuid(dev, &data->in_client_uuid); 396 if (!me_cl || 397 (me_cl->props.fixed_address && !dev->allow_fixed_address)) { 398 dev_dbg(dev->dev, "Cannot connect to FW Client UUID = %pUl\n", 399 &data->in_client_uuid); 400 mei_me_cl_put(me_cl); 401 return -ENOTTY; 402 } 403 404 dev_dbg(dev->dev, "Connect to FW Client ID = %d\n", 405 me_cl->client_id); 406 dev_dbg(dev->dev, "FW Client - Protocol Version = %d\n", 407 me_cl->props.protocol_version); 408 dev_dbg(dev->dev, "FW Client - Max Msg Len = %d\n", 409 me_cl->props.max_msg_length); 410 411 /* if we're connecting to amthif client then we will use the 412 * existing connection 413 */ 414 if (uuid_le_cmp(data->in_client_uuid, mei_amthif_guid) == 0) { 415 dev_dbg(dev->dev, "FW Client is amthi\n"); 416 if (!mei_cl_is_connected(&dev->iamthif_cl)) { 417 rets = -ENODEV; 418 goto end; 419 } 420 mei_cl_unlink(cl); 421 422 kfree(cl); 423 cl = NULL; 424 dev->iamthif_open_count++; 425 file->private_data = &dev->iamthif_cl; 426 427 client = &data->out_client_properties; 428 client->max_msg_length = me_cl->props.max_msg_length; 429 client->protocol_version = me_cl->props.protocol_version; 430 rets = dev->iamthif_cl.status; 431 432 goto end; 433 } 434 435 /* prepare the output buffer */ 436 client = &data->out_client_properties; 437 client->max_msg_length = me_cl->props.max_msg_length; 438 client->protocol_version = me_cl->props.protocol_version; 439 dev_dbg(dev->dev, "Can connect?\n"); 440 441 rets = mei_cl_connect(cl, me_cl, file); 442 443 end: 444 mei_me_cl_put(me_cl); 445 return rets; 446 } 447 448 /** 449 * mei_ioctl_client_notify_request - 450 * propagate event notification request to client 451 * 452 * @file: pointer to file structure 453 * @request: 0 - disable, 1 - enable 454 * 455 * Return: 0 on success , <0 on error 456 */ 457 static int mei_ioctl_client_notify_request(struct file *file, u32 request) 458 { 459 struct mei_cl *cl = file->private_data; 460 461 if (request != MEI_HBM_NOTIFICATION_START && 462 request != MEI_HBM_NOTIFICATION_STOP) 463 return -EINVAL; 464 465 return mei_cl_notify_request(cl, file, (u8)request); 466 } 467 468 /** 469 * mei_ioctl_client_notify_get - wait for notification request 470 * 471 * @file: pointer to file structure 472 * @notify_get: 0 - disable, 1 - enable 473 * 474 * Return: 0 on success , <0 on error 475 */ 476 static int mei_ioctl_client_notify_get(struct file *file, u32 *notify_get) 477 { 478 struct mei_cl *cl = file->private_data; 479 bool notify_ev; 480 bool block = (file->f_flags & O_NONBLOCK) == 0; 481 int rets; 482 483 rets = mei_cl_notify_get(cl, block, ¬ify_ev); 484 if (rets) 485 return rets; 486 487 *notify_get = notify_ev ? 1 : 0; 488 return 0; 489 } 490 491 /** 492 * mei_ioctl - the IOCTL function 493 * 494 * @file: pointer to file structure 495 * @cmd: ioctl command 496 * @data: pointer to mei message structure 497 * 498 * Return: 0 on success , <0 on error 499 */ 500 static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data) 501 { 502 struct mei_device *dev; 503 struct mei_cl *cl = file->private_data; 504 struct mei_connect_client_data connect_data; 505 u32 notify_get, notify_req; 506 int rets; 507 508 509 if (WARN_ON(!cl || !cl->dev)) 510 return -ENODEV; 511 512 dev = cl->dev; 513 514 dev_dbg(dev->dev, "IOCTL cmd = 0x%x", cmd); 515 516 mutex_lock(&dev->device_lock); 517 if (dev->dev_state != MEI_DEV_ENABLED) { 518 rets = -ENODEV; 519 goto out; 520 } 521 522 switch (cmd) { 523 case IOCTL_MEI_CONNECT_CLIENT: 524 dev_dbg(dev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n"); 525 if (copy_from_user(&connect_data, (char __user *)data, 526 sizeof(struct mei_connect_client_data))) { 527 dev_dbg(dev->dev, "failed to copy data from userland\n"); 528 rets = -EFAULT; 529 goto out; 530 } 531 532 rets = mei_ioctl_connect_client(file, &connect_data); 533 if (rets) 534 goto out; 535 536 /* if all is ok, copying the data back to user. */ 537 if (copy_to_user((char __user *)data, &connect_data, 538 sizeof(struct mei_connect_client_data))) { 539 dev_dbg(dev->dev, "failed to copy data to userland\n"); 540 rets = -EFAULT; 541 goto out; 542 } 543 544 break; 545 546 case IOCTL_MEI_NOTIFY_SET: 547 dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_SET.\n"); 548 if (copy_from_user(¬ify_req, 549 (char __user *)data, sizeof(notify_req))) { 550 dev_dbg(dev->dev, "failed to copy data from userland\n"); 551 rets = -EFAULT; 552 goto out; 553 } 554 rets = mei_ioctl_client_notify_request(file, notify_req); 555 break; 556 557 case IOCTL_MEI_NOTIFY_GET: 558 dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_GET.\n"); 559 rets = mei_ioctl_client_notify_get(file, ¬ify_get); 560 if (rets) 561 goto out; 562 563 dev_dbg(dev->dev, "copy connect data to user\n"); 564 if (copy_to_user((char __user *)data, 565 ¬ify_get, sizeof(notify_get))) { 566 dev_dbg(dev->dev, "failed to copy data to userland\n"); 567 rets = -EFAULT; 568 goto out; 569 570 } 571 break; 572 573 default: 574 dev_err(dev->dev, ": unsupported ioctl %d.\n", cmd); 575 rets = -ENOIOCTLCMD; 576 } 577 578 out: 579 mutex_unlock(&dev->device_lock); 580 return rets; 581 } 582 583 /** 584 * mei_compat_ioctl - the compat IOCTL function 585 * 586 * @file: pointer to file structure 587 * @cmd: ioctl command 588 * @data: pointer to mei message structure 589 * 590 * Return: 0 on success , <0 on error 591 */ 592 #ifdef CONFIG_COMPAT 593 static long mei_compat_ioctl(struct file *file, 594 unsigned int cmd, unsigned long data) 595 { 596 return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data)); 597 } 598 #endif 599 600 601 /** 602 * mei_poll - the poll function 603 * 604 * @file: pointer to file structure 605 * @wait: pointer to poll_table structure 606 * 607 * Return: poll mask 608 */ 609 static unsigned int mei_poll(struct file *file, poll_table *wait) 610 { 611 unsigned long req_events = poll_requested_events(wait); 612 struct mei_cl *cl = file->private_data; 613 struct mei_device *dev; 614 unsigned int mask = 0; 615 bool notify_en; 616 617 if (WARN_ON(!cl || !cl->dev)) 618 return POLLERR; 619 620 dev = cl->dev; 621 622 mutex_lock(&dev->device_lock); 623 624 notify_en = cl->notify_en && (req_events & POLLPRI); 625 626 if (dev->dev_state != MEI_DEV_ENABLED || 627 !mei_cl_is_connected(cl)) { 628 mask = POLLERR; 629 goto out; 630 } 631 632 if (cl == &dev->iamthif_cl) { 633 mask = mei_amthif_poll(dev, file, wait); 634 goto out; 635 } 636 637 if (notify_en) { 638 poll_wait(file, &cl->ev_wait, wait); 639 if (cl->notify_ev) 640 mask |= POLLPRI; 641 } 642 643 if (req_events & (POLLIN | POLLRDNORM)) { 644 poll_wait(file, &cl->rx_wait, wait); 645 646 if (!list_empty(&cl->rd_completed)) 647 mask |= POLLIN | POLLRDNORM; 648 else 649 mei_cl_read_start(cl, 0, file); 650 } 651 652 out: 653 mutex_unlock(&dev->device_lock); 654 return mask; 655 } 656 657 /** 658 * mei_fasync - asynchronous io support 659 * 660 * @fd: file descriptor 661 * @file: pointer to file structure 662 * @band: band bitmap 663 * 664 * Return: negative on error, 665 * 0 if it did no changes, 666 * and positive a process was added or deleted 667 */ 668 static int mei_fasync(int fd, struct file *file, int band) 669 { 670 671 struct mei_cl *cl = file->private_data; 672 673 if (!mei_cl_is_connected(cl)) 674 return -ENODEV; 675 676 return fasync_helper(fd, file, band, &cl->ev_async); 677 } 678 679 /** 680 * fw_status_show - mei device attribute show method 681 * 682 * @device: device pointer 683 * @attr: attribute pointer 684 * @buf: char out buffer 685 * 686 * Return: number of the bytes printed into buf or error 687 */ 688 static ssize_t fw_status_show(struct device *device, 689 struct device_attribute *attr, char *buf) 690 { 691 struct mei_device *dev = dev_get_drvdata(device); 692 struct mei_fw_status fw_status; 693 int err, i; 694 ssize_t cnt = 0; 695 696 mutex_lock(&dev->device_lock); 697 err = mei_fw_status(dev, &fw_status); 698 mutex_unlock(&dev->device_lock); 699 if (err) { 700 dev_err(device, "read fw_status error = %d\n", err); 701 return err; 702 } 703 704 for (i = 0; i < fw_status.count; i++) 705 cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%08X\n", 706 fw_status.status[i]); 707 return cnt; 708 } 709 static DEVICE_ATTR_RO(fw_status); 710 711 static struct attribute *mei_attrs[] = { 712 &dev_attr_fw_status.attr, 713 NULL 714 }; 715 ATTRIBUTE_GROUPS(mei); 716 717 /* 718 * file operations structure will be used for mei char device. 719 */ 720 static const struct file_operations mei_fops = { 721 .owner = THIS_MODULE, 722 .read = mei_read, 723 .unlocked_ioctl = mei_ioctl, 724 #ifdef CONFIG_COMPAT 725 .compat_ioctl = mei_compat_ioctl, 726 #endif 727 .open = mei_open, 728 .release = mei_release, 729 .write = mei_write, 730 .poll = mei_poll, 731 .fasync = mei_fasync, 732 .llseek = no_llseek 733 }; 734 735 static struct class *mei_class; 736 static dev_t mei_devt; 737 #define MEI_MAX_DEVS MINORMASK 738 static DEFINE_MUTEX(mei_minor_lock); 739 static DEFINE_IDR(mei_idr); 740 741 /** 742 * mei_minor_get - obtain next free device minor number 743 * 744 * @dev: device pointer 745 * 746 * Return: allocated minor, or -ENOSPC if no free minor left 747 */ 748 static int mei_minor_get(struct mei_device *dev) 749 { 750 int ret; 751 752 mutex_lock(&mei_minor_lock); 753 ret = idr_alloc(&mei_idr, dev, 0, MEI_MAX_DEVS, GFP_KERNEL); 754 if (ret >= 0) 755 dev->minor = ret; 756 else if (ret == -ENOSPC) 757 dev_err(dev->dev, "too many mei devices\n"); 758 759 mutex_unlock(&mei_minor_lock); 760 return ret; 761 } 762 763 /** 764 * mei_minor_free - mark device minor number as free 765 * 766 * @dev: device pointer 767 */ 768 static void mei_minor_free(struct mei_device *dev) 769 { 770 mutex_lock(&mei_minor_lock); 771 idr_remove(&mei_idr, dev->minor); 772 mutex_unlock(&mei_minor_lock); 773 } 774 775 int mei_register(struct mei_device *dev, struct device *parent) 776 { 777 struct device *clsdev; /* class device */ 778 int ret, devno; 779 780 ret = mei_minor_get(dev); 781 if (ret < 0) 782 return ret; 783 784 /* Fill in the data structures */ 785 devno = MKDEV(MAJOR(mei_devt), dev->minor); 786 cdev_init(&dev->cdev, &mei_fops); 787 dev->cdev.owner = parent->driver->owner; 788 789 /* Add the device */ 790 ret = cdev_add(&dev->cdev, devno, 1); 791 if (ret) { 792 dev_err(parent, "unable to add device %d:%d\n", 793 MAJOR(mei_devt), dev->minor); 794 goto err_dev_add; 795 } 796 797 clsdev = device_create_with_groups(mei_class, parent, devno, 798 dev, mei_groups, 799 "mei%d", dev->minor); 800 801 if (IS_ERR(clsdev)) { 802 dev_err(parent, "unable to create device %d:%d\n", 803 MAJOR(mei_devt), dev->minor); 804 ret = PTR_ERR(clsdev); 805 goto err_dev_create; 806 } 807 808 ret = mei_dbgfs_register(dev, dev_name(clsdev)); 809 if (ret) { 810 dev_err(clsdev, "cannot register debugfs ret = %d\n", ret); 811 goto err_dev_dbgfs; 812 } 813 814 return 0; 815 816 err_dev_dbgfs: 817 device_destroy(mei_class, devno); 818 err_dev_create: 819 cdev_del(&dev->cdev); 820 err_dev_add: 821 mei_minor_free(dev); 822 return ret; 823 } 824 EXPORT_SYMBOL_GPL(mei_register); 825 826 void mei_deregister(struct mei_device *dev) 827 { 828 int devno; 829 830 devno = dev->cdev.dev; 831 cdev_del(&dev->cdev); 832 833 mei_dbgfs_deregister(dev); 834 835 device_destroy(mei_class, devno); 836 837 mei_minor_free(dev); 838 } 839 EXPORT_SYMBOL_GPL(mei_deregister); 840 841 static int __init mei_init(void) 842 { 843 int ret; 844 845 mei_class = class_create(THIS_MODULE, "mei"); 846 if (IS_ERR(mei_class)) { 847 pr_err("couldn't create class\n"); 848 ret = PTR_ERR(mei_class); 849 goto err; 850 } 851 852 ret = alloc_chrdev_region(&mei_devt, 0, MEI_MAX_DEVS, "mei"); 853 if (ret < 0) { 854 pr_err("unable to allocate char dev region\n"); 855 goto err_class; 856 } 857 858 ret = mei_cl_bus_init(); 859 if (ret < 0) { 860 pr_err("unable to initialize bus\n"); 861 goto err_chrdev; 862 } 863 864 return 0; 865 866 err_chrdev: 867 unregister_chrdev_region(mei_devt, MEI_MAX_DEVS); 868 err_class: 869 class_destroy(mei_class); 870 err: 871 return ret; 872 } 873 874 static void __exit mei_exit(void) 875 { 876 unregister_chrdev_region(mei_devt, MEI_MAX_DEVS); 877 class_destroy(mei_class); 878 mei_cl_bus_exit(); 879 } 880 881 module_init(mei_init); 882 module_exit(mei_exit); 883 884 MODULE_AUTHOR("Intel Corporation"); 885 MODULE_DESCRIPTION("Intel(R) Management Engine Interface"); 886 MODULE_LICENSE("GPL v2"); 887 888