1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2003-2018, Intel Corporation. All rights reserved. 4 * Intel Management Engine Interface (Intel MEI) Linux driver 5 */ 6 7 #include <linux/module.h> 8 #include <linux/moduleparam.h> 9 #include <linux/kernel.h> 10 #include <linux/device.h> 11 #include <linux/slab.h> 12 #include <linux/fs.h> 13 #include <linux/errno.h> 14 #include <linux/types.h> 15 #include <linux/fcntl.h> 16 #include <linux/poll.h> 17 #include <linux/init.h> 18 #include <linux/ioctl.h> 19 #include <linux/cdev.h> 20 #include <linux/sched/signal.h> 21 #include <linux/uuid.h> 22 #include <linux/compat.h> 23 #include <linux/jiffies.h> 24 #include <linux/interrupt.h> 25 26 #include <linux/mei.h> 27 28 #include "mei_dev.h" 29 #include "client.h" 30 31 static struct class *mei_class; 32 static dev_t mei_devt; 33 #define MEI_MAX_DEVS MINORMASK 34 static DEFINE_MUTEX(mei_minor_lock); 35 static DEFINE_IDR(mei_idr); 36 37 /** 38 * mei_open - the open function 39 * 40 * @inode: pointer to inode structure 41 * @file: pointer to file structure 42 * 43 * Return: 0 on success, <0 on error 44 */ 45 static int mei_open(struct inode *inode, struct file *file) 46 { 47 struct mei_device *dev; 48 struct mei_cl *cl; 49 50 int err; 51 52 dev = container_of(inode->i_cdev, struct mei_device, cdev); 53 if (!dev) 54 return -ENODEV; 55 56 mutex_lock(&dev->device_lock); 57 58 if (dev->dev_state != MEI_DEV_ENABLED) { 59 dev_dbg(dev->dev, "dev_state != MEI_ENABLED dev_state = %s\n", 60 mei_dev_state_str(dev->dev_state)); 61 err = -ENODEV; 62 goto err_unlock; 63 } 64 65 cl = mei_cl_alloc_linked(dev); 66 if (IS_ERR(cl)) { 67 err = PTR_ERR(cl); 68 goto err_unlock; 69 } 70 71 cl->fp = file; 72 file->private_data = cl; 73 74 mutex_unlock(&dev->device_lock); 75 76 return nonseekable_open(inode, file); 77 78 err_unlock: 79 mutex_unlock(&dev->device_lock); 80 return err; 81 } 82 83 /** 84 * mei_release - the release function 85 * 86 * @inode: pointer to inode structure 87 * @file: pointer to file structure 88 * 89 * Return: 0 on success, <0 on error 90 */ 91 static int mei_release(struct inode *inode, struct file *file) 92 { 93 struct mei_cl *cl = file->private_data; 94 struct mei_device *dev; 95 int rets; 96 97 if (WARN_ON(!cl || !cl->dev)) 98 return -ENODEV; 99 100 dev = cl->dev; 101 102 mutex_lock(&dev->device_lock); 103 104 rets = mei_cl_disconnect(cl); 105 106 mei_cl_flush_queues(cl, file); 107 cl_dbg(dev, cl, "removing\n"); 108 109 mei_cl_unlink(cl); 110 111 file->private_data = NULL; 112 113 kfree(cl); 114 115 mutex_unlock(&dev->device_lock); 116 return rets; 117 } 118 119 120 /** 121 * mei_read - the read function. 122 * 123 * @file: pointer to file structure 124 * @ubuf: pointer to user buffer 125 * @length: buffer length 126 * @offset: data offset in buffer 127 * 128 * Return: >=0 data length on success , <0 on error 129 */ 130 static ssize_t mei_read(struct file *file, char __user *ubuf, 131 size_t length, loff_t *offset) 132 { 133 struct mei_cl *cl = file->private_data; 134 struct mei_device *dev; 135 struct mei_cl_cb *cb = NULL; 136 bool nonblock = !!(file->f_flags & O_NONBLOCK); 137 ssize_t rets; 138 139 if (WARN_ON(!cl || !cl->dev)) 140 return -ENODEV; 141 142 dev = cl->dev; 143 144 145 mutex_lock(&dev->device_lock); 146 if (dev->dev_state != MEI_DEV_ENABLED) { 147 rets = -ENODEV; 148 goto out; 149 } 150 151 if (length == 0) { 152 rets = 0; 153 goto out; 154 } 155 156 if (ubuf == NULL) { 157 rets = -EMSGSIZE; 158 goto out; 159 } 160 161 cb = mei_cl_read_cb(cl, file); 162 if (cb) 163 goto copy_buffer; 164 165 if (*offset > 0) 166 *offset = 0; 167 168 rets = mei_cl_read_start(cl, length, file); 169 if (rets && rets != -EBUSY) { 170 cl_dbg(dev, cl, "mei start read failure status = %zd\n", rets); 171 goto out; 172 } 173 174 if (nonblock) { 175 rets = -EAGAIN; 176 goto out; 177 } 178 179 mutex_unlock(&dev->device_lock); 180 if (wait_event_interruptible(cl->rx_wait, 181 !list_empty(&cl->rd_completed) || 182 !mei_cl_is_connected(cl))) { 183 if (signal_pending(current)) 184 return -EINTR; 185 return -ERESTARTSYS; 186 } 187 mutex_lock(&dev->device_lock); 188 189 if (!mei_cl_is_connected(cl)) { 190 rets = -ENODEV; 191 goto out; 192 } 193 194 cb = mei_cl_read_cb(cl, file); 195 if (!cb) { 196 rets = 0; 197 goto out; 198 } 199 200 copy_buffer: 201 /* now copy the data to user space */ 202 if (cb->status) { 203 rets = cb->status; 204 cl_dbg(dev, cl, "read operation failed %zd\n", rets); 205 goto free; 206 } 207 208 cl_dbg(dev, cl, "buf.size = %zu buf.idx = %zu offset = %lld\n", 209 cb->buf.size, cb->buf_idx, *offset); 210 if (*offset >= cb->buf_idx) { 211 rets = 0; 212 goto free; 213 } 214 215 /* length is being truncated to PAGE_SIZE, 216 * however buf_idx may point beyond that */ 217 length = min_t(size_t, length, cb->buf_idx - *offset); 218 219 if (copy_to_user(ubuf, cb->buf.data + *offset, length)) { 220 dev_dbg(dev->dev, "failed to copy data to userland\n"); 221 rets = -EFAULT; 222 goto free; 223 } 224 225 rets = length; 226 *offset += length; 227 /* not all data was read, keep the cb */ 228 if (*offset < cb->buf_idx) 229 goto out; 230 231 free: 232 mei_io_cb_free(cb); 233 *offset = 0; 234 235 out: 236 cl_dbg(dev, cl, "end mei read rets = %zd\n", rets); 237 mutex_unlock(&dev->device_lock); 238 return rets; 239 } 240 /** 241 * mei_write - the write function. 242 * 243 * @file: pointer to file structure 244 * @ubuf: pointer to user buffer 245 * @length: buffer length 246 * @offset: data offset in buffer 247 * 248 * Return: >=0 data length on success , <0 on error 249 */ 250 static ssize_t mei_write(struct file *file, const char __user *ubuf, 251 size_t length, loff_t *offset) 252 { 253 struct mei_cl *cl = file->private_data; 254 struct mei_cl_cb *cb; 255 struct mei_device *dev; 256 ssize_t rets; 257 258 if (WARN_ON(!cl || !cl->dev)) 259 return -ENODEV; 260 261 dev = cl->dev; 262 263 mutex_lock(&dev->device_lock); 264 265 if (dev->dev_state != MEI_DEV_ENABLED) { 266 rets = -ENODEV; 267 goto out; 268 } 269 270 if (!mei_cl_is_connected(cl)) { 271 cl_err(dev, cl, "is not connected"); 272 rets = -ENODEV; 273 goto out; 274 } 275 276 if (!mei_me_cl_is_active(cl->me_cl)) { 277 rets = -ENOTTY; 278 goto out; 279 } 280 281 if (length > mei_cl_mtu(cl)) { 282 rets = -EFBIG; 283 goto out; 284 } 285 286 if (length == 0) { 287 rets = 0; 288 goto out; 289 } 290 291 while (cl->tx_cb_queued >= dev->tx_queue_limit) { 292 if (file->f_flags & O_NONBLOCK) { 293 rets = -EAGAIN; 294 goto out; 295 } 296 mutex_unlock(&dev->device_lock); 297 rets = wait_event_interruptible(cl->tx_wait, 298 cl->writing_state == MEI_WRITE_COMPLETE || 299 (!mei_cl_is_connected(cl))); 300 mutex_lock(&dev->device_lock); 301 if (rets) { 302 if (signal_pending(current)) 303 rets = -EINTR; 304 goto out; 305 } 306 if (!mei_cl_is_connected(cl)) { 307 rets = -ENODEV; 308 goto out; 309 } 310 } 311 312 cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file); 313 if (!cb) { 314 rets = -ENOMEM; 315 goto out; 316 } 317 318 rets = copy_from_user(cb->buf.data, ubuf, length); 319 if (rets) { 320 dev_dbg(dev->dev, "failed to copy data from userland\n"); 321 rets = -EFAULT; 322 mei_io_cb_free(cb); 323 goto out; 324 } 325 326 rets = mei_cl_write(cl, cb); 327 out: 328 mutex_unlock(&dev->device_lock); 329 return rets; 330 } 331 332 /** 333 * mei_ioctl_connect_client - the connect to fw client IOCTL function 334 * 335 * @file: private data of the file object 336 * @data: IOCTL connect data, input and output parameters 337 * 338 * Locking: called under "dev->device_lock" lock 339 * 340 * Return: 0 on success, <0 on failure. 341 */ 342 static int mei_ioctl_connect_client(struct file *file, 343 struct mei_connect_client_data *data) 344 { 345 struct mei_device *dev; 346 struct mei_client *client; 347 struct mei_me_client *me_cl; 348 struct mei_cl *cl; 349 int rets; 350 351 cl = file->private_data; 352 dev = cl->dev; 353 354 if (dev->dev_state != MEI_DEV_ENABLED) 355 return -ENODEV; 356 357 if (cl->state != MEI_FILE_INITIALIZING && 358 cl->state != MEI_FILE_DISCONNECTED) 359 return -EBUSY; 360 361 /* find ME client we're trying to connect to */ 362 me_cl = mei_me_cl_by_uuid(dev, &data->in_client_uuid); 363 if (!me_cl) { 364 dev_dbg(dev->dev, "Cannot connect to FW Client UUID = %pUl\n", 365 &data->in_client_uuid); 366 rets = -ENOTTY; 367 goto end; 368 } 369 370 if (me_cl->props.fixed_address) { 371 bool forbidden = dev->override_fixed_address ? 372 !dev->allow_fixed_address : !dev->hbm_f_fa_supported; 373 if (forbidden) { 374 dev_dbg(dev->dev, "Connection forbidden to FW Client UUID = %pUl\n", 375 &data->in_client_uuid); 376 rets = -ENOTTY; 377 goto end; 378 } 379 } 380 381 dev_dbg(dev->dev, "Connect to FW Client ID = %d\n", 382 me_cl->client_id); 383 dev_dbg(dev->dev, "FW Client - Protocol Version = %d\n", 384 me_cl->props.protocol_version); 385 dev_dbg(dev->dev, "FW Client - Max Msg Len = %d\n", 386 me_cl->props.max_msg_length); 387 388 /* prepare the output buffer */ 389 client = &data->out_client_properties; 390 client->max_msg_length = me_cl->props.max_msg_length; 391 client->protocol_version = me_cl->props.protocol_version; 392 dev_dbg(dev->dev, "Can connect?\n"); 393 394 rets = mei_cl_connect(cl, me_cl, file); 395 396 end: 397 mei_me_cl_put(me_cl); 398 return rets; 399 } 400 401 /** 402 * mei_ioctl_client_notify_request - 403 * propagate event notification request to client 404 * 405 * @file: pointer to file structure 406 * @request: 0 - disable, 1 - enable 407 * 408 * Return: 0 on success , <0 on error 409 */ 410 static int mei_ioctl_client_notify_request(const struct file *file, u32 request) 411 { 412 struct mei_cl *cl = file->private_data; 413 414 if (request != MEI_HBM_NOTIFICATION_START && 415 request != MEI_HBM_NOTIFICATION_STOP) 416 return -EINVAL; 417 418 return mei_cl_notify_request(cl, file, (u8)request); 419 } 420 421 /** 422 * mei_ioctl_client_notify_get - wait for notification request 423 * 424 * @file: pointer to file structure 425 * @notify_get: 0 - disable, 1 - enable 426 * 427 * Return: 0 on success , <0 on error 428 */ 429 static int mei_ioctl_client_notify_get(const struct file *file, u32 *notify_get) 430 { 431 struct mei_cl *cl = file->private_data; 432 bool notify_ev; 433 bool block = (file->f_flags & O_NONBLOCK) == 0; 434 int rets; 435 436 rets = mei_cl_notify_get(cl, block, ¬ify_ev); 437 if (rets) 438 return rets; 439 440 *notify_get = notify_ev ? 1 : 0; 441 return 0; 442 } 443 444 /** 445 * mei_ioctl - the IOCTL function 446 * 447 * @file: pointer to file structure 448 * @cmd: ioctl command 449 * @data: pointer to mei message structure 450 * 451 * Return: 0 on success , <0 on error 452 */ 453 static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data) 454 { 455 struct mei_device *dev; 456 struct mei_cl *cl = file->private_data; 457 struct mei_connect_client_data connect_data; 458 u32 notify_get, notify_req; 459 int rets; 460 461 462 if (WARN_ON(!cl || !cl->dev)) 463 return -ENODEV; 464 465 dev = cl->dev; 466 467 dev_dbg(dev->dev, "IOCTL cmd = 0x%x", cmd); 468 469 mutex_lock(&dev->device_lock); 470 if (dev->dev_state != MEI_DEV_ENABLED) { 471 rets = -ENODEV; 472 goto out; 473 } 474 475 switch (cmd) { 476 case IOCTL_MEI_CONNECT_CLIENT: 477 dev_dbg(dev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n"); 478 if (copy_from_user(&connect_data, (char __user *)data, 479 sizeof(struct mei_connect_client_data))) { 480 dev_dbg(dev->dev, "failed to copy data from userland\n"); 481 rets = -EFAULT; 482 goto out; 483 } 484 485 rets = mei_ioctl_connect_client(file, &connect_data); 486 if (rets) 487 goto out; 488 489 /* if all is ok, copying the data back to user. */ 490 if (copy_to_user((char __user *)data, &connect_data, 491 sizeof(struct mei_connect_client_data))) { 492 dev_dbg(dev->dev, "failed to copy data to userland\n"); 493 rets = -EFAULT; 494 goto out; 495 } 496 497 break; 498 499 case IOCTL_MEI_NOTIFY_SET: 500 dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_SET.\n"); 501 if (copy_from_user(¬ify_req, 502 (char __user *)data, sizeof(notify_req))) { 503 dev_dbg(dev->dev, "failed to copy data from userland\n"); 504 rets = -EFAULT; 505 goto out; 506 } 507 rets = mei_ioctl_client_notify_request(file, notify_req); 508 break; 509 510 case IOCTL_MEI_NOTIFY_GET: 511 dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_GET.\n"); 512 rets = mei_ioctl_client_notify_get(file, ¬ify_get); 513 if (rets) 514 goto out; 515 516 dev_dbg(dev->dev, "copy connect data to user\n"); 517 if (copy_to_user((char __user *)data, 518 ¬ify_get, sizeof(notify_get))) { 519 dev_dbg(dev->dev, "failed to copy data to userland\n"); 520 rets = -EFAULT; 521 goto out; 522 523 } 524 break; 525 526 default: 527 rets = -ENOIOCTLCMD; 528 } 529 530 out: 531 mutex_unlock(&dev->device_lock); 532 return rets; 533 } 534 535 /** 536 * mei_poll - the poll function 537 * 538 * @file: pointer to file structure 539 * @wait: pointer to poll_table structure 540 * 541 * Return: poll mask 542 */ 543 static __poll_t mei_poll(struct file *file, poll_table *wait) 544 { 545 __poll_t req_events = poll_requested_events(wait); 546 struct mei_cl *cl = file->private_data; 547 struct mei_device *dev; 548 __poll_t mask = 0; 549 bool notify_en; 550 551 if (WARN_ON(!cl || !cl->dev)) 552 return EPOLLERR; 553 554 dev = cl->dev; 555 556 mutex_lock(&dev->device_lock); 557 558 notify_en = cl->notify_en && (req_events & EPOLLPRI); 559 560 if (dev->dev_state != MEI_DEV_ENABLED || 561 !mei_cl_is_connected(cl)) { 562 mask = EPOLLERR; 563 goto out; 564 } 565 566 if (notify_en) { 567 poll_wait(file, &cl->ev_wait, wait); 568 if (cl->notify_ev) 569 mask |= EPOLLPRI; 570 } 571 572 if (req_events & (EPOLLIN | EPOLLRDNORM)) { 573 poll_wait(file, &cl->rx_wait, wait); 574 575 if (!list_empty(&cl->rd_completed)) 576 mask |= EPOLLIN | EPOLLRDNORM; 577 else 578 mei_cl_read_start(cl, mei_cl_mtu(cl), file); 579 } 580 581 if (req_events & (EPOLLOUT | EPOLLWRNORM)) { 582 poll_wait(file, &cl->tx_wait, wait); 583 if (cl->tx_cb_queued < dev->tx_queue_limit) 584 mask |= EPOLLOUT | EPOLLWRNORM; 585 } 586 587 out: 588 mutex_unlock(&dev->device_lock); 589 return mask; 590 } 591 592 /** 593 * mei_cl_is_write_queued - check if the client has pending writes. 594 * 595 * @cl: writing host client 596 * 597 * Return: true if client is writing, false otherwise. 598 */ 599 static bool mei_cl_is_write_queued(struct mei_cl *cl) 600 { 601 struct mei_device *dev = cl->dev; 602 struct mei_cl_cb *cb; 603 604 list_for_each_entry(cb, &dev->write_list, list) 605 if (cb->cl == cl) 606 return true; 607 list_for_each_entry(cb, &dev->write_waiting_list, list) 608 if (cb->cl == cl) 609 return true; 610 return false; 611 } 612 613 /** 614 * mei_fsync - the fsync handler 615 * 616 * @fp: pointer to file structure 617 * @start: unused 618 * @end: unused 619 * @datasync: unused 620 * 621 * Return: 0 on success, -ENODEV if client is not connected 622 */ 623 static int mei_fsync(struct file *fp, loff_t start, loff_t end, int datasync) 624 { 625 struct mei_cl *cl = fp->private_data; 626 struct mei_device *dev; 627 int rets; 628 629 if (WARN_ON(!cl || !cl->dev)) 630 return -ENODEV; 631 632 dev = cl->dev; 633 634 mutex_lock(&dev->device_lock); 635 636 if (dev->dev_state != MEI_DEV_ENABLED || !mei_cl_is_connected(cl)) { 637 rets = -ENODEV; 638 goto out; 639 } 640 641 while (mei_cl_is_write_queued(cl)) { 642 mutex_unlock(&dev->device_lock); 643 rets = wait_event_interruptible(cl->tx_wait, 644 cl->writing_state == MEI_WRITE_COMPLETE || 645 !mei_cl_is_connected(cl)); 646 mutex_lock(&dev->device_lock); 647 if (rets) { 648 if (signal_pending(current)) 649 rets = -EINTR; 650 goto out; 651 } 652 if (!mei_cl_is_connected(cl)) { 653 rets = -ENODEV; 654 goto out; 655 } 656 } 657 rets = 0; 658 out: 659 mutex_unlock(&dev->device_lock); 660 return rets; 661 } 662 663 /** 664 * mei_fasync - asynchronous io support 665 * 666 * @fd: file descriptor 667 * @file: pointer to file structure 668 * @band: band bitmap 669 * 670 * Return: negative on error, 671 * 0 if it did no changes, 672 * and positive a process was added or deleted 673 */ 674 static int mei_fasync(int fd, struct file *file, int band) 675 { 676 677 struct mei_cl *cl = file->private_data; 678 679 if (!mei_cl_is_connected(cl)) 680 return -ENODEV; 681 682 return fasync_helper(fd, file, band, &cl->ev_async); 683 } 684 685 /** 686 * trc_show - mei device trc attribute show method 687 * 688 * @device: device pointer 689 * @attr: attribute pointer 690 * @buf: char out buffer 691 * 692 * Return: number of the bytes printed into buf or error 693 */ 694 static ssize_t trc_show(struct device *device, 695 struct device_attribute *attr, char *buf) 696 { 697 struct mei_device *dev = dev_get_drvdata(device); 698 u32 trc; 699 int ret; 700 701 ret = mei_trc_status(dev, &trc); 702 if (ret) 703 return ret; 704 return sprintf(buf, "%08X\n", trc); 705 } 706 static DEVICE_ATTR_RO(trc); 707 708 /** 709 * fw_status_show - mei device fw_status attribute show method 710 * 711 * @device: device pointer 712 * @attr: attribute pointer 713 * @buf: char out buffer 714 * 715 * Return: number of the bytes printed into buf or error 716 */ 717 static ssize_t fw_status_show(struct device *device, 718 struct device_attribute *attr, char *buf) 719 { 720 struct mei_device *dev = dev_get_drvdata(device); 721 struct mei_fw_status fw_status; 722 int err, i; 723 ssize_t cnt = 0; 724 725 mutex_lock(&dev->device_lock); 726 err = mei_fw_status(dev, &fw_status); 727 mutex_unlock(&dev->device_lock); 728 if (err) { 729 dev_err(device, "read fw_status error = %d\n", err); 730 return err; 731 } 732 733 for (i = 0; i < fw_status.count; i++) 734 cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%08X\n", 735 fw_status.status[i]); 736 return cnt; 737 } 738 static DEVICE_ATTR_RO(fw_status); 739 740 /** 741 * hbm_ver_show - display HBM protocol version negotiated with FW 742 * 743 * @device: device pointer 744 * @attr: attribute pointer 745 * @buf: char out buffer 746 * 747 * Return: number of the bytes printed into buf or error 748 */ 749 static ssize_t hbm_ver_show(struct device *device, 750 struct device_attribute *attr, char *buf) 751 { 752 struct mei_device *dev = dev_get_drvdata(device); 753 struct hbm_version ver; 754 755 mutex_lock(&dev->device_lock); 756 ver = dev->version; 757 mutex_unlock(&dev->device_lock); 758 759 return sprintf(buf, "%u.%u\n", ver.major_version, ver.minor_version); 760 } 761 static DEVICE_ATTR_RO(hbm_ver); 762 763 /** 764 * hbm_ver_drv_show - display HBM protocol version advertised by driver 765 * 766 * @device: device pointer 767 * @attr: attribute pointer 768 * @buf: char out buffer 769 * 770 * Return: number of the bytes printed into buf or error 771 */ 772 static ssize_t hbm_ver_drv_show(struct device *device, 773 struct device_attribute *attr, char *buf) 774 { 775 return sprintf(buf, "%u.%u\n", HBM_MAJOR_VERSION, HBM_MINOR_VERSION); 776 } 777 static DEVICE_ATTR_RO(hbm_ver_drv); 778 779 static ssize_t tx_queue_limit_show(struct device *device, 780 struct device_attribute *attr, char *buf) 781 { 782 struct mei_device *dev = dev_get_drvdata(device); 783 u8 size = 0; 784 785 mutex_lock(&dev->device_lock); 786 size = dev->tx_queue_limit; 787 mutex_unlock(&dev->device_lock); 788 789 return snprintf(buf, PAGE_SIZE, "%u\n", size); 790 } 791 792 static ssize_t tx_queue_limit_store(struct device *device, 793 struct device_attribute *attr, 794 const char *buf, size_t count) 795 { 796 struct mei_device *dev = dev_get_drvdata(device); 797 u8 limit; 798 unsigned int inp; 799 int err; 800 801 err = kstrtouint(buf, 10, &inp); 802 if (err) 803 return err; 804 if (inp > MEI_TX_QUEUE_LIMIT_MAX || inp < MEI_TX_QUEUE_LIMIT_MIN) 805 return -EINVAL; 806 limit = inp; 807 808 mutex_lock(&dev->device_lock); 809 dev->tx_queue_limit = limit; 810 mutex_unlock(&dev->device_lock); 811 812 return count; 813 } 814 static DEVICE_ATTR_RW(tx_queue_limit); 815 816 /** 817 * fw_ver_show - display ME FW version 818 * 819 * @device: device pointer 820 * @attr: attribute pointer 821 * @buf: char out buffer 822 * 823 * Return: number of the bytes printed into buf or error 824 */ 825 static ssize_t fw_ver_show(struct device *device, 826 struct device_attribute *attr, char *buf) 827 { 828 struct mei_device *dev = dev_get_drvdata(device); 829 struct mei_fw_version *ver; 830 ssize_t cnt = 0; 831 int i; 832 833 ver = dev->fw_ver; 834 835 for (i = 0; i < MEI_MAX_FW_VER_BLOCKS; i++) 836 cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%u:%u.%u.%u.%u\n", 837 ver[i].platform, ver[i].major, ver[i].minor, 838 ver[i].hotfix, ver[i].buildno); 839 return cnt; 840 } 841 static DEVICE_ATTR_RO(fw_ver); 842 843 /** 844 * dev_state_show - display device state 845 * 846 * @device: device pointer 847 * @attr: attribute pointer 848 * @buf: char out buffer 849 * 850 * Return: number of the bytes printed into buf or error 851 */ 852 static ssize_t dev_state_show(struct device *device, 853 struct device_attribute *attr, char *buf) 854 { 855 struct mei_device *dev = dev_get_drvdata(device); 856 enum mei_dev_state dev_state; 857 858 mutex_lock(&dev->device_lock); 859 dev_state = dev->dev_state; 860 mutex_unlock(&dev->device_lock); 861 862 return sprintf(buf, "%s", mei_dev_state_str(dev_state)); 863 } 864 static DEVICE_ATTR_RO(dev_state); 865 866 /** 867 * dev_set_devstate: set to new device state and notify sysfs file. 868 * 869 * @dev: mei_device 870 * @state: new device state 871 */ 872 void mei_set_devstate(struct mei_device *dev, enum mei_dev_state state) 873 { 874 struct device *clsdev; 875 876 if (dev->dev_state == state) 877 return; 878 879 dev->dev_state = state; 880 881 clsdev = class_find_device_by_devt(mei_class, dev->cdev.dev); 882 if (clsdev) { 883 sysfs_notify(&clsdev->kobj, NULL, "dev_state"); 884 put_device(clsdev); 885 } 886 } 887 888 static struct attribute *mei_attrs[] = { 889 &dev_attr_fw_status.attr, 890 &dev_attr_hbm_ver.attr, 891 &dev_attr_hbm_ver_drv.attr, 892 &dev_attr_tx_queue_limit.attr, 893 &dev_attr_fw_ver.attr, 894 &dev_attr_dev_state.attr, 895 &dev_attr_trc.attr, 896 NULL 897 }; 898 ATTRIBUTE_GROUPS(mei); 899 900 /* 901 * file operations structure will be used for mei char device. 902 */ 903 static const struct file_operations mei_fops = { 904 .owner = THIS_MODULE, 905 .read = mei_read, 906 .unlocked_ioctl = mei_ioctl, 907 .compat_ioctl = compat_ptr_ioctl, 908 .open = mei_open, 909 .release = mei_release, 910 .write = mei_write, 911 .poll = mei_poll, 912 .fsync = mei_fsync, 913 .fasync = mei_fasync, 914 .llseek = no_llseek 915 }; 916 917 /** 918 * mei_minor_get - obtain next free device minor number 919 * 920 * @dev: device pointer 921 * 922 * Return: allocated minor, or -ENOSPC if no free minor left 923 */ 924 static int mei_minor_get(struct mei_device *dev) 925 { 926 int ret; 927 928 mutex_lock(&mei_minor_lock); 929 ret = idr_alloc(&mei_idr, dev, 0, MEI_MAX_DEVS, GFP_KERNEL); 930 if (ret >= 0) 931 dev->minor = ret; 932 else if (ret == -ENOSPC) 933 dev_err(dev->dev, "too many mei devices\n"); 934 935 mutex_unlock(&mei_minor_lock); 936 return ret; 937 } 938 939 /** 940 * mei_minor_free - mark device minor number as free 941 * 942 * @dev: device pointer 943 */ 944 static void mei_minor_free(struct mei_device *dev) 945 { 946 mutex_lock(&mei_minor_lock); 947 idr_remove(&mei_idr, dev->minor); 948 mutex_unlock(&mei_minor_lock); 949 } 950 951 int mei_register(struct mei_device *dev, struct device *parent) 952 { 953 struct device *clsdev; /* class device */ 954 int ret, devno; 955 956 ret = mei_minor_get(dev); 957 if (ret < 0) 958 return ret; 959 960 /* Fill in the data structures */ 961 devno = MKDEV(MAJOR(mei_devt), dev->minor); 962 cdev_init(&dev->cdev, &mei_fops); 963 dev->cdev.owner = parent->driver->owner; 964 965 /* Add the device */ 966 ret = cdev_add(&dev->cdev, devno, 1); 967 if (ret) { 968 dev_err(parent, "unable to add device %d:%d\n", 969 MAJOR(mei_devt), dev->minor); 970 goto err_dev_add; 971 } 972 973 clsdev = device_create_with_groups(mei_class, parent, devno, 974 dev, mei_groups, 975 "mei%d", dev->minor); 976 977 if (IS_ERR(clsdev)) { 978 dev_err(parent, "unable to create device %d:%d\n", 979 MAJOR(mei_devt), dev->minor); 980 ret = PTR_ERR(clsdev); 981 goto err_dev_create; 982 } 983 984 mei_dbgfs_register(dev, dev_name(clsdev)); 985 986 return 0; 987 988 err_dev_create: 989 cdev_del(&dev->cdev); 990 err_dev_add: 991 mei_minor_free(dev); 992 return ret; 993 } 994 EXPORT_SYMBOL_GPL(mei_register); 995 996 void mei_deregister(struct mei_device *dev) 997 { 998 int devno; 999 1000 devno = dev->cdev.dev; 1001 cdev_del(&dev->cdev); 1002 1003 mei_dbgfs_deregister(dev); 1004 1005 device_destroy(mei_class, devno); 1006 1007 mei_minor_free(dev); 1008 } 1009 EXPORT_SYMBOL_GPL(mei_deregister); 1010 1011 static int __init mei_init(void) 1012 { 1013 int ret; 1014 1015 mei_class = class_create(THIS_MODULE, "mei"); 1016 if (IS_ERR(mei_class)) { 1017 pr_err("couldn't create class\n"); 1018 ret = PTR_ERR(mei_class); 1019 goto err; 1020 } 1021 1022 ret = alloc_chrdev_region(&mei_devt, 0, MEI_MAX_DEVS, "mei"); 1023 if (ret < 0) { 1024 pr_err("unable to allocate char dev region\n"); 1025 goto err_class; 1026 } 1027 1028 ret = mei_cl_bus_init(); 1029 if (ret < 0) { 1030 pr_err("unable to initialize bus\n"); 1031 goto err_chrdev; 1032 } 1033 1034 return 0; 1035 1036 err_chrdev: 1037 unregister_chrdev_region(mei_devt, MEI_MAX_DEVS); 1038 err_class: 1039 class_destroy(mei_class); 1040 err: 1041 return ret; 1042 } 1043 1044 static void __exit mei_exit(void) 1045 { 1046 unregister_chrdev_region(mei_devt, MEI_MAX_DEVS); 1047 class_destroy(mei_class); 1048 mei_cl_bus_exit(); 1049 } 1050 1051 module_init(mei_init); 1052 module_exit(mei_exit); 1053 1054 MODULE_AUTHOR("Intel Corporation"); 1055 MODULE_DESCRIPTION("Intel(R) Management Engine Interface"); 1056 MODULE_LICENSE("GPL v2"); 1057 1058