drivers/misc/mei/main.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
mei_open
mei_release
mei_read
mei_write
mei_ioctl_connect_client
mei_ioctl_client_notify_request
mei_ioctl_client_notify_get
mei_ioctl
mei_compat_ioctl
mei_poll
mei_cl_is_write_queued
mei_fsync
mei_fasync
fw_status_show
hbm_ver_show
hbm_ver_drv_show
tx_queue_limit_show
tx_queue_limit_store
fw_ver_show
dev_state_show
mei_set_devstate
mei_minor_get
mei_minor_free
mei_register
mei_deregister
mei_init
mei_exit
   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, &notify_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(&notify_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, &notify_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                                 &notify_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_compat_ioctl - the compat IOCTL function
 537  *
 538  * @file: pointer to file structure
 539  * @cmd: ioctl command
 540  * @data: pointer to mei message structure
 541  *
 542  * Return: 0 on success , <0 on error
 543  */
 544 #ifdef CONFIG_COMPAT
 545 static long mei_compat_ioctl(struct file *file,
 546                         unsigned int cmd, unsigned long data)
 547 {
 548         return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data));
 549 }
 550 #endif
 551 
 552 
 553 /**
 554  * mei_poll - the poll function
 555  *
 556  * @file: pointer to file structure
 557  * @wait: pointer to poll_table structure
 558  *
 559  * Return: poll mask
 560  */
 561 static __poll_t mei_poll(struct file *file, poll_table *wait)
 562 {
 563         __poll_t req_events = poll_requested_events(wait);
 564         struct mei_cl *cl = file->private_data;
 565         struct mei_device *dev;
 566         __poll_t mask = 0;
 567         bool notify_en;
 568 
 569         if (WARN_ON(!cl || !cl->dev))
 570                 return EPOLLERR;
 571 
 572         dev = cl->dev;
 573 
 574         mutex_lock(&dev->device_lock);
 575 
 576         notify_en = cl->notify_en && (req_events & EPOLLPRI);
 577 
 578         if (dev->dev_state != MEI_DEV_ENABLED ||
 579             !mei_cl_is_connected(cl)) {
 580                 mask = EPOLLERR;
 581                 goto out;
 582         }
 583 
 584         if (notify_en) {
 585                 poll_wait(file, &cl->ev_wait, wait);
 586                 if (cl->notify_ev)
 587                         mask |= EPOLLPRI;
 588         }
 589 
 590         if (req_events & (EPOLLIN | EPOLLRDNORM)) {
 591                 poll_wait(file, &cl->rx_wait, wait);
 592 
 593                 if (!list_empty(&cl->rd_completed))
 594                         mask |= EPOLLIN | EPOLLRDNORM;
 595                 else
 596                         mei_cl_read_start(cl, mei_cl_mtu(cl), file);
 597         }
 598 
 599         if (req_events & (EPOLLOUT | EPOLLWRNORM)) {
 600                 poll_wait(file, &cl->tx_wait, wait);
 601                 if (cl->tx_cb_queued < dev->tx_queue_limit)
 602                         mask |= EPOLLOUT | EPOLLWRNORM;
 603         }
 604 
 605 out:
 606         mutex_unlock(&dev->device_lock);
 607         return mask;
 608 }
 609 
 610 /**
 611  * mei_cl_is_write_queued - check if the client has pending writes.
 612  *
 613  * @cl: writing host client
 614  *
 615  * Return: true if client is writing, false otherwise.
 616  */
 617 static bool mei_cl_is_write_queued(struct mei_cl *cl)
 618 {
 619         struct mei_device *dev = cl->dev;
 620         struct mei_cl_cb *cb;
 621 
 622         list_for_each_entry(cb, &dev->write_list, list)
 623                 if (cb->cl == cl)
 624                         return true;
 625         list_for_each_entry(cb, &dev->write_waiting_list, list)
 626                 if (cb->cl == cl)
 627                         return true;
 628         return false;
 629 }
 630 
 631 /**
 632  * mei_fsync - the fsync handler
 633  *
 634  * @fp:       pointer to file structure
 635  * @start:    unused
 636  * @end:      unused
 637  * @datasync: unused
 638  *
 639  * Return: 0 on success, -ENODEV if client is not connected
 640  */
 641 static int mei_fsync(struct file *fp, loff_t start, loff_t end, int datasync)
 642 {
 643         struct mei_cl *cl = fp->private_data;
 644         struct mei_device *dev;
 645         int rets;
 646 
 647         if (WARN_ON(!cl || !cl->dev))
 648                 return -ENODEV;
 649 
 650         dev = cl->dev;
 651 
 652         mutex_lock(&dev->device_lock);
 653 
 654         if (dev->dev_state != MEI_DEV_ENABLED || !mei_cl_is_connected(cl)) {
 655                 rets = -ENODEV;
 656                 goto out;
 657         }
 658 
 659         while (mei_cl_is_write_queued(cl)) {
 660                 mutex_unlock(&dev->device_lock);
 661                 rets = wait_event_interruptible(cl->tx_wait,
 662                                 cl->writing_state == MEI_WRITE_COMPLETE ||
 663                                 !mei_cl_is_connected(cl));
 664                 mutex_lock(&dev->device_lock);
 665                 if (rets) {
 666                         if (signal_pending(current))
 667                                 rets = -EINTR;
 668                         goto out;
 669                 }
 670                 if (!mei_cl_is_connected(cl)) {
 671                         rets = -ENODEV;
 672                         goto out;
 673                 }
 674         }
 675         rets = 0;
 676 out:
 677         mutex_unlock(&dev->device_lock);
 678         return rets;
 679 }
 680 
 681 /**
 682  * mei_fasync - asynchronous io support
 683  *
 684  * @fd: file descriptor
 685  * @file: pointer to file structure
 686  * @band: band bitmap
 687  *
 688  * Return: negative on error,
 689  *         0 if it did no changes,
 690  *         and positive a process was added or deleted
 691  */
 692 static int mei_fasync(int fd, struct file *file, int band)
 693 {
 694 
 695         struct mei_cl *cl = file->private_data;
 696 
 697         if (!mei_cl_is_connected(cl))
 698                 return -ENODEV;
 699 
 700         return fasync_helper(fd, file, band, &cl->ev_async);
 701 }
 702 
 703 /**
 704  * fw_status_show - mei device fw_status attribute show method
 705  *
 706  * @device: device pointer
 707  * @attr: attribute pointer
 708  * @buf:  char out buffer
 709  *
 710  * Return: number of the bytes printed into buf or error
 711  */
 712 static ssize_t fw_status_show(struct device *device,
 713                 struct device_attribute *attr, char *buf)
 714 {
 715         struct mei_device *dev = dev_get_drvdata(device);
 716         struct mei_fw_status fw_status;
 717         int err, i;
 718         ssize_t cnt = 0;
 719 
 720         mutex_lock(&dev->device_lock);
 721         err = mei_fw_status(dev, &fw_status);
 722         mutex_unlock(&dev->device_lock);
 723         if (err) {
 724                 dev_err(device, "read fw_status error = %d\n", err);
 725                 return err;
 726         }
 727 
 728         for (i = 0; i < fw_status.count; i++)
 729                 cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%08X\n",
 730                                 fw_status.status[i]);
 731         return cnt;
 732 }
 733 static DEVICE_ATTR_RO(fw_status);
 734 
 735 /**
 736  * hbm_ver_show - display HBM protocol version negotiated with FW
 737  *
 738  * @device: device pointer
 739  * @attr: attribute pointer
 740  * @buf:  char out buffer
 741  *
 742  * Return: number of the bytes printed into buf or error
 743  */
 744 static ssize_t hbm_ver_show(struct device *device,
 745                             struct device_attribute *attr, char *buf)
 746 {
 747         struct mei_device *dev = dev_get_drvdata(device);
 748         struct hbm_version ver;
 749 
 750         mutex_lock(&dev->device_lock);
 751         ver = dev->version;
 752         mutex_unlock(&dev->device_lock);
 753 
 754         return sprintf(buf, "%u.%u\n", ver.major_version, ver.minor_version);
 755 }
 756 static DEVICE_ATTR_RO(hbm_ver);
 757 
 758 /**
 759  * hbm_ver_drv_show - display HBM protocol version advertised by driver
 760  *
 761  * @device: device pointer
 762  * @attr: attribute pointer
 763  * @buf:  char out buffer
 764  *
 765  * Return: number of the bytes printed into buf or error
 766  */
 767 static ssize_t hbm_ver_drv_show(struct device *device,
 768                                 struct device_attribute *attr, char *buf)
 769 {
 770         return sprintf(buf, "%u.%u\n", HBM_MAJOR_VERSION, HBM_MINOR_VERSION);
 771 }
 772 static DEVICE_ATTR_RO(hbm_ver_drv);
 773 
 774 static ssize_t tx_queue_limit_show(struct device *device,
 775                                    struct device_attribute *attr, char *buf)
 776 {
 777         struct mei_device *dev = dev_get_drvdata(device);
 778         u8 size = 0;
 779 
 780         mutex_lock(&dev->device_lock);
 781         size = dev->tx_queue_limit;
 782         mutex_unlock(&dev->device_lock);
 783 
 784         return snprintf(buf, PAGE_SIZE, "%u\n", size);
 785 }
 786 
 787 static ssize_t tx_queue_limit_store(struct device *device,
 788                                     struct device_attribute *attr,
 789                                     const char *buf, size_t count)
 790 {
 791         struct mei_device *dev = dev_get_drvdata(device);
 792         u8 limit;
 793         unsigned int inp;
 794         int err;
 795 
 796         err = kstrtouint(buf, 10, &inp);
 797         if (err)
 798                 return err;
 799         if (inp > MEI_TX_QUEUE_LIMIT_MAX || inp < MEI_TX_QUEUE_LIMIT_MIN)
 800                 return -EINVAL;
 801         limit = inp;
 802 
 803         mutex_lock(&dev->device_lock);
 804         dev->tx_queue_limit = limit;
 805         mutex_unlock(&dev->device_lock);
 806 
 807         return count;
 808 }
 809 static DEVICE_ATTR_RW(tx_queue_limit);
 810 
 811 /**
 812  * fw_ver_show - display ME FW version
 813  *
 814  * @device: device pointer
 815  * @attr: attribute pointer
 816  * @buf:  char out buffer
 817  *
 818  * Return: number of the bytes printed into buf or error
 819  */
 820 static ssize_t fw_ver_show(struct device *device,
 821                            struct device_attribute *attr, char *buf)
 822 {
 823         struct mei_device *dev = dev_get_drvdata(device);
 824         struct mei_fw_version *ver;
 825         ssize_t cnt = 0;
 826         int i;
 827 
 828         ver = dev->fw_ver;
 829 
 830         for (i = 0; i < MEI_MAX_FW_VER_BLOCKS; i++)
 831                 cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%u:%u.%u.%u.%u\n",
 832                                  ver[i].platform, ver[i].major, ver[i].minor,
 833                                  ver[i].hotfix, ver[i].buildno);
 834         return cnt;
 835 }
 836 static DEVICE_ATTR_RO(fw_ver);
 837 
 838 /**
 839  * dev_state_show - display device state
 840  *
 841  * @device: device pointer
 842  * @attr: attribute pointer
 843  * @buf:  char out buffer
 844  *
 845  * Return: number of the bytes printed into buf or error
 846  */
 847 static ssize_t dev_state_show(struct device *device,
 848                               struct device_attribute *attr, char *buf)
 849 {
 850         struct mei_device *dev = dev_get_drvdata(device);
 851         enum mei_dev_state dev_state;
 852 
 853         mutex_lock(&dev->device_lock);
 854         dev_state = dev->dev_state;
 855         mutex_unlock(&dev->device_lock);
 856 
 857         return sprintf(buf, "%s", mei_dev_state_str(dev_state));
 858 }
 859 static DEVICE_ATTR_RO(dev_state);
 860 
 861 /**
 862  * dev_set_devstate: set to new device state and notify sysfs file.
 863  *
 864  * @dev: mei_device
 865  * @state: new device state
 866  */
 867 void mei_set_devstate(struct mei_device *dev, enum mei_dev_state state)
 868 {
 869         struct device *clsdev;
 870 
 871         if (dev->dev_state == state)
 872                 return;
 873 
 874         dev->dev_state = state;
 875 
 876         clsdev = class_find_device_by_devt(mei_class, dev->cdev.dev);
 877         if (clsdev) {
 878                 sysfs_notify(&clsdev->kobj, NULL, "dev_state");
 879                 put_device(clsdev);
 880         }
 881 }
 882 
 883 static struct attribute *mei_attrs[] = {
 884         &dev_attr_fw_status.attr,
 885         &dev_attr_hbm_ver.attr,
 886         &dev_attr_hbm_ver_drv.attr,
 887         &dev_attr_tx_queue_limit.attr,
 888         &dev_attr_fw_ver.attr,
 889         &dev_attr_dev_state.attr,
 890         NULL
 891 };
 892 ATTRIBUTE_GROUPS(mei);
 893 
 894 /*
 895  * file operations structure will be used for mei char device.
 896  */
 897 static const struct file_operations mei_fops = {
 898         .owner = THIS_MODULE,
 899         .read = mei_read,
 900         .unlocked_ioctl = mei_ioctl,
 901 #ifdef CONFIG_COMPAT
 902         .compat_ioctl = mei_compat_ioctl,
 903 #endif
 904         .open = mei_open,
 905         .release = mei_release,
 906         .write = mei_write,
 907         .poll = mei_poll,
 908         .fsync = mei_fsync,
 909         .fasync = mei_fasync,
 910         .llseek = no_llseek
 911 };
 912 
 913 /**
 914  * mei_minor_get - obtain next free device minor number
 915  *
 916  * @dev:  device pointer
 917  *
 918  * Return: allocated minor, or -ENOSPC if no free minor left
 919  */
 920 static int mei_minor_get(struct mei_device *dev)
 921 {
 922         int ret;
 923 
 924         mutex_lock(&mei_minor_lock);
 925         ret = idr_alloc(&mei_idr, dev, 0, MEI_MAX_DEVS, GFP_KERNEL);
 926         if (ret >= 0)
 927                 dev->minor = ret;
 928         else if (ret == -ENOSPC)
 929                 dev_err(dev->dev, "too many mei devices\n");
 930 
 931         mutex_unlock(&mei_minor_lock);
 932         return ret;
 933 }
 934 
 935 /**
 936  * mei_minor_free - mark device minor number as free
 937  *
 938  * @dev:  device pointer
 939  */
 940 static void mei_minor_free(struct mei_device *dev)
 941 {
 942         mutex_lock(&mei_minor_lock);
 943         idr_remove(&mei_idr, dev->minor);
 944         mutex_unlock(&mei_minor_lock);
 945 }
 946 
 947 int mei_register(struct mei_device *dev, struct device *parent)
 948 {
 949         struct device *clsdev; /* class device */
 950         int ret, devno;
 951 
 952         ret = mei_minor_get(dev);
 953         if (ret < 0)
 954                 return ret;
 955 
 956         /* Fill in the data structures */
 957         devno = MKDEV(MAJOR(mei_devt), dev->minor);
 958         cdev_init(&dev->cdev, &mei_fops);
 959         dev->cdev.owner = parent->driver->owner;
 960 
 961         /* Add the device */
 962         ret = cdev_add(&dev->cdev, devno, 1);
 963         if (ret) {
 964                 dev_err(parent, "unable to add device %d:%d\n",
 965                         MAJOR(mei_devt), dev->minor);
 966                 goto err_dev_add;
 967         }
 968 
 969         clsdev = device_create_with_groups(mei_class, parent, devno,
 970                                            dev, mei_groups,
 971                                            "mei%d", dev->minor);
 972 
 973         if (IS_ERR(clsdev)) {
 974                 dev_err(parent, "unable to create device %d:%d\n",
 975                         MAJOR(mei_devt), dev->minor);
 976                 ret = PTR_ERR(clsdev);
 977                 goto err_dev_create;
 978         }
 979 
 980         mei_dbgfs_register(dev, dev_name(clsdev));
 981 
 982         return 0;
 983 
 984 err_dev_create:
 985         cdev_del(&dev->cdev);
 986 err_dev_add:
 987         mei_minor_free(dev);
 988         return ret;
 989 }
 990 EXPORT_SYMBOL_GPL(mei_register);
 991 
 992 void mei_deregister(struct mei_device *dev)
 993 {
 994         int devno;
 995 
 996         devno = dev->cdev.dev;
 997         cdev_del(&dev->cdev);
 998 
 999         mei_dbgfs_deregister(dev);
1000 
1001         device_destroy(mei_class, devno);
1002 
1003         mei_minor_free(dev);
1004 }
1005 EXPORT_SYMBOL_GPL(mei_deregister);
1006 
1007 static int __init mei_init(void)
1008 {
1009         int ret;
1010 
1011         mei_class = class_create(THIS_MODULE, "mei");
1012         if (IS_ERR(mei_class)) {
1013                 pr_err("couldn't create class\n");
1014                 ret = PTR_ERR(mei_class);
1015                 goto err;
1016         }
1017 
1018         ret = alloc_chrdev_region(&mei_devt, 0, MEI_MAX_DEVS, "mei");
1019         if (ret < 0) {
1020                 pr_err("unable to allocate char dev region\n");
1021                 goto err_class;
1022         }
1023 
1024         ret = mei_cl_bus_init();
1025         if (ret < 0) {
1026                 pr_err("unable to initialize bus\n");
1027                 goto err_chrdev;
1028         }
1029 
1030         return 0;
1031 
1032 err_chrdev:
1033         unregister_chrdev_region(mei_devt, MEI_MAX_DEVS);
1034 err_class:
1035         class_destroy(mei_class);
1036 err:
1037         return ret;
1038 }
1039 
1040 static void __exit mei_exit(void)
1041 {
1042         unregister_chrdev_region(mei_devt, MEI_MAX_DEVS);
1043         class_destroy(mei_class);
1044         mei_cl_bus_exit();
1045 }
1046 
1047 module_init(mei_init);
1048 module_exit(mei_exit);
1049 
1050 MODULE_AUTHOR("Intel Corporation");
1051 MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
1052 MODULE_LICENSE("GPL v2");
1053
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/misc/mei/main.c

DEFINITIONS
