Pileus Git - ~andy/linux/blob - drivers/misc/mei/amthif.c

   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
  17 #include <linux/kernel.h>
  18 #include <linux/fs.h>
  19 #include <linux/errno.h>
  20 #include <linux/types.h>
  21 #include <linux/fcntl.h>
  22 #include <linux/aio.h>
  23 #include <linux/pci.h>
  24 #include <linux/init.h>
  25 #include <linux/ioctl.h>
  26 #include <linux/cdev.h>
  27 #include <linux/list.h>
  28 #include <linux/delay.h>
  29 #include <linux/sched.h>
  30 #include <linux/uuid.h>
  31 #include <linux/jiffies.h>
  32 #include <linux/uaccess.h>
  33
  34 #include <linux/mei.h>
  35
  36 #include "mei_dev.h"
  37 #include "hbm.h"
  38 #include "hw-me.h"
  39 #include "client.h"
  40
  41 const uuid_le mei_amthif_guid  = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d,
  42                                          0xac, 0xa8, 0x46, 0xe0,
  43                                          0xff, 0x65, 0x81, 0x4c);
  44
  45 /**
  46  * mei_amthif_reset_params - initializes mei device iamthif
  47  *
  48  * @dev: the device structure
  49  */
  50 void mei_amthif_reset_params(struct mei_device *dev)
  51 {
  52         /* reset iamthif parameters. */
  53         dev->iamthif_current_cb = NULL;
  54         dev->iamthif_msg_buf_size = 0;
  55         dev->iamthif_msg_buf_index = 0;
  56         dev->iamthif_canceled = false;
  57         dev->iamthif_ioctl = false;
  58         dev->iamthif_state = MEI_IAMTHIF_IDLE;
  59         dev->iamthif_timer = 0;
  60         dev->iamthif_stall_timer = 0;
  61         dev->iamthif_open_count = 0;
  62 }
  63
  64 /**
  65  * mei_amthif_host_init - mei initialization amthif client.
  66  *
  67  * @dev: the device structure
  68  *
  69  */
  70 int mei_amthif_host_init(struct mei_device *dev)
  71 {
  72         struct mei_cl *cl = &dev->iamthif_cl;
  73         unsigned char *msg_buf;
  74         int ret, i;
  75
  76         dev->iamthif_state = MEI_IAMTHIF_IDLE;
  77
  78         mei_cl_init(cl, dev);
  79
  80         i = mei_me_cl_by_uuid(dev, &mei_amthif_guid);
  81         if (i < 0) {
  82                 ret = i;
  83                 dev_info(&dev->pdev->dev,
  84                         "amthif: failed to find the client %d\n", ret);
  85                 return ret;
  86         }
  87
  88         cl->me_client_id = dev->me_clients[i].client_id;
  89
  90         /* Assign iamthif_mtu to the value received from ME  */
  91
  92         dev->iamthif_mtu = dev->me_clients[i].props.max_msg_length;
  93         dev_dbg(&dev->pdev->dev, "IAMTHIF_MTU = %d\n",
  94                         dev->me_clients[i].props.max_msg_length);
  95
  96         kfree(dev->iamthif_msg_buf);
  97         dev->iamthif_msg_buf = NULL;
  98
  99         /* allocate storage for ME message buffer */
 100         msg_buf = kcalloc(dev->iamthif_mtu,
 101                         sizeof(unsigned char), GFP_KERNEL);
 102         if (!msg_buf) {
 103                 dev_err(&dev->pdev->dev, "amthif: memory allocation for ME message buffer failed.\n");
 104                 return -ENOMEM;
 105         }
 106
 107         dev->iamthif_msg_buf = msg_buf;
 108
 109         ret = mei_cl_link(cl, MEI_IAMTHIF_HOST_CLIENT_ID);
 110
 111         if (ret < 0) {
 112                 dev_err(&dev->pdev->dev,
 113                         "amthif: failed link client %d\n", ret);
 114                 return ret;
 115         }
 116
 117         cl->state = MEI_FILE_CONNECTING;
 118
 119         if (mei_hbm_cl_connect_req(dev, cl)) {
 120                 dev_dbg(&dev->pdev->dev, "amthif: Failed to connect to ME client\n");
 121                 cl->state = MEI_FILE_DISCONNECTED;
 122                 cl->host_client_id = 0;
 123         } else {
 124                 cl->timer_count = MEI_CONNECT_TIMEOUT;
 125         }
 126         return 0;
 127 }
 128
 129 /**
 130  * mei_amthif_find_read_list_entry - finds a amthilist entry for current file
 131  *
 132  * @dev: the device structure
 133  * @file: pointer to file object
 134  *
 135  * returns   returned a list entry on success, NULL on failure.
 136  */
 137 struct mei_cl_cb *mei_amthif_find_read_list_entry(struct mei_device *dev,
 138                                                 struct file *file)
 139 {
 140         struct mei_cl_cb *pos = NULL;
 141         struct mei_cl_cb *next = NULL;
 142
 143         list_for_each_entry_safe(pos, next,
 144                                 &dev->amthif_rd_complete_list.list, list) {
 145                 if (pos->cl && pos->cl == &dev->iamthif_cl &&
 146                         pos->file_object == file)
 147                         return pos;
 148         }
 149         return NULL;
 150 }
 151
 152
 153 /**
 154  * mei_amthif_read - read data from AMTHIF client
 155  *
 156  * @dev: the device structure
 157  * @if_num:  minor number
 158  * @file: pointer to file object
 159  * @*ubuf: pointer to user data in user space
 160  * @length: data length to read
 161  * @offset: data read offset
 162  *
 163  * Locking: called under "dev->device_lock" lock
 164  *
 165  * returns
 166  *  returned data length on success,
 167  *  zero if no data to read,
 168  *  negative on failure.
 169  */
 170 int mei_amthif_read(struct mei_device *dev, struct file *file,
 171                char __user *ubuf, size_t length, loff_t *offset)
 172 {
 173         int rets;
 174         int wait_ret;
 175         struct mei_cl_cb *cb = NULL;
 176         struct mei_cl *cl = file->private_data;
 177         unsigned long timeout;
 178         int i;
 179
 180         /* Only possible if we are in timeout */
 181         if (!cl || cl != &dev->iamthif_cl) {
 182                 dev_dbg(&dev->pdev->dev, "bad file ext.\n");
 183                 return -ETIMEDOUT;
 184         }
 185
 186         i = mei_me_cl_by_id(dev, dev->iamthif_cl.me_client_id);
 187
 188         if (i < 0) {
 189                 dev_dbg(&dev->pdev->dev, "amthif client not found.\n");
 190                 return -ENODEV;
 191         }
 192         dev_dbg(&dev->pdev->dev, "checking amthif data\n");
 193         cb = mei_amthif_find_read_list_entry(dev, file);
 194
 195         /* Check for if we can block or not*/
 196         if (cb == NULL && file->f_flags & O_NONBLOCK)
 197                 return -EAGAIN;
 198
 199
 200         dev_dbg(&dev->pdev->dev, "waiting for amthif data\n");
 201         while (cb == NULL) {
 202                 /* unlock the Mutex */
 203                 mutex_unlock(&dev->device_lock);
 204
 205                 wait_ret = wait_event_interruptible(dev->iamthif_cl.wait,
 206                         (cb = mei_amthif_find_read_list_entry(dev, file)));
 207
 208                 /* Locking again the Mutex */
 209                 mutex_lock(&dev->device_lock);
 210
 211                 if (wait_ret)
 212                         return -ERESTARTSYS;
 213
 214                 dev_dbg(&dev->pdev->dev, "woke up from sleep\n");
 215         }
 216
 217
 218         dev_dbg(&dev->pdev->dev, "Got amthif data\n");
 219         dev->iamthif_timer = 0;
 220
 221         if (cb) {
 222                 timeout = cb->read_time +
 223                         mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
 224                 dev_dbg(&dev->pdev->dev, "amthif timeout = %lud\n",
 225                                 timeout);
 226
 227                 if  (time_after(jiffies, timeout)) {
 228                         dev_dbg(&dev->pdev->dev, "amthif Time out\n");
 229                         /* 15 sec for the message has expired */
 230                         list_del(&cb->list);
 231                         rets = -ETIMEDOUT;
 232                         goto free;
 233                 }
 234         }
 235         /* if the whole message will fit remove it from the list */
 236         if (cb->buf_idx >= *offset && length >= (cb->buf_idx - *offset))
 237                 list_del(&cb->list);
 238         else if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
 239                 /* end of the message has been reached */
 240                 list_del(&cb->list);
 241                 rets = 0;
 242                 goto free;
 243         }
 244                 /* else means that not full buffer will be read and do not
 245                  * remove message from deletion list
 246                  */
 247
 248         dev_dbg(&dev->pdev->dev, "amthif cb->response_buffer size - %d\n",
 249             cb->response_buffer.size);
 250         dev_dbg(&dev->pdev->dev, "amthif cb->buf_idx - %lu\n", cb->buf_idx);
 251
 252         /* length is being truncated to PAGE_SIZE, however,
 253          * the buf_idx may point beyond */
 254         length = min_t(size_t, length, (cb->buf_idx - *offset));
 255
 256         if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length))
 257                 rets = -EFAULT;
 258         else {
 259                 rets = length;
 260                 if ((*offset + length) < cb->buf_idx) {
 261                         *offset += length;
 262                         goto out;
 263                 }
 264         }
 265 free:
 266         dev_dbg(&dev->pdev->dev, "free amthif cb memory.\n");
 267         *offset = 0;
 268         mei_io_cb_free(cb);
 269 out:
 270         return rets;
 271 }
 272
 273 /**
 274  * mei_amthif_send_cmd - send amthif command to the ME
 275  *
 276  * @dev: the device structure
 277  * @cb: mei call back struct
 278  *
 279  * returns 0 on success, <0 on failure.
 280  *
 281  */
 282 static int mei_amthif_send_cmd(struct mei_device *dev, struct mei_cl_cb *cb)
 283 {
 284         struct mei_msg_hdr mei_hdr;
 285         int ret;
 286
 287         if (!dev || !cb)
 288                 return -ENODEV;
 289
 290         dev_dbg(&dev->pdev->dev, "write data to amthif client.\n");
 291
 292         dev->iamthif_state = MEI_IAMTHIF_WRITING;
 293         dev->iamthif_current_cb = cb;
 294         dev->iamthif_file_object = cb->file_object;
 295         dev->iamthif_canceled = false;
 296         dev->iamthif_ioctl = true;
 297         dev->iamthif_msg_buf_size = cb->request_buffer.size;
 298         memcpy(dev->iamthif_msg_buf, cb->request_buffer.data,
 299                cb->request_buffer.size);
 300
 301         ret = mei_cl_flow_ctrl_creds(&dev->iamthif_cl);
 302         if (ret < 0)
 303                 return ret;
 304
 305         if (ret && dev->hbuf_is_ready) {
 306                 ret = 0;
 307                 dev->hbuf_is_ready = false;
 308                 if (cb->request_buffer.size > mei_hbuf_max_len(dev)) {
 309                         mei_hdr.length = mei_hbuf_max_len(dev);
 310                         mei_hdr.msg_complete = 0;
 311                 } else {
 312                         mei_hdr.length = cb->request_buffer.size;
 313                         mei_hdr.msg_complete = 1;
 314                 }
 315
 316                 mei_hdr.host_addr = dev->iamthif_cl.host_client_id;
 317                 mei_hdr.me_addr = dev->iamthif_cl.me_client_id;
 318                 mei_hdr.reserved = 0;
 319                 mei_hdr.internal = 0;
 320                 dev->iamthif_msg_buf_index += mei_hdr.length;
 321                 ret = mei_write_message(dev, &mei_hdr, dev->iamthif_msg_buf);
 322                 if (ret)
 323                         return ret;
 324
 325                 if (mei_hdr.msg_complete) {
 326                         if (mei_cl_flow_ctrl_reduce(&dev->iamthif_cl))
 327                                 return -EIO;
 328                         dev->iamthif_flow_control_pending = true;
 329                         dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
 330                         dev_dbg(&dev->pdev->dev, "add amthif cb to write waiting list\n");
 331                         dev->iamthif_current_cb = cb;
 332                         dev->iamthif_file_object = cb->file_object;
 333                         list_add_tail(&cb->list, &dev->write_waiting_list.list);
 334                 } else {
 335                         dev_dbg(&dev->pdev->dev, "message does not complete, so add amthif cb to write list.\n");
 336                         list_add_tail(&cb->list, &dev->write_list.list);
 337                 }
 338         } else {
 339                 if (!dev->hbuf_is_ready)
 340                         dev_dbg(&dev->pdev->dev, "host buffer is not empty");
 341
 342                 dev_dbg(&dev->pdev->dev, "No flow control credentials, so add iamthif cb to write list.\n");
 343                 list_add_tail(&cb->list, &dev->write_list.list);
 344         }
 345         return 0;
 346 }
 347
 348 /**
 349  * mei_amthif_write - write amthif data to amthif client
 350  *
 351  * @dev: the device structure
 352  * @cb: mei call back struct
 353  *
 354  * returns 0 on success, <0 on failure.
 355  *
 356  */
 357 int mei_amthif_write(struct mei_device *dev, struct mei_cl_cb *cb)
 358 {
 359         int ret;
 360
 361         if (!dev || !cb)
 362                 return -ENODEV;
 363
 364         ret = mei_io_cb_alloc_resp_buf(cb, dev->iamthif_mtu);
 365         if (ret)
 366                 return ret;
 367
 368         cb->fop_type = MEI_FOP_IOCTL;
 369
 370         if (!list_empty(&dev->amthif_cmd_list.list) ||
 371             dev->iamthif_state != MEI_IAMTHIF_IDLE) {
 372                 dev_dbg(&dev->pdev->dev,
 373                         "amthif state = %d\n", dev->iamthif_state);
 374                 dev_dbg(&dev->pdev->dev, "AMTHIF: add cb to the wait list\n");
 375                 list_add_tail(&cb->list, &dev->amthif_cmd_list.list);
 376                 return 0;
 377         }
 378         return mei_amthif_send_cmd(dev, cb);
 379 }
 380 /**
 381  * mei_amthif_run_next_cmd
 382  *
 383  * @dev: the device structure
 384  *
 385  * returns 0 on success, <0 on failure.
 386  */
 387 void mei_amthif_run_next_cmd(struct mei_device *dev)
 388 {
 389         struct mei_cl_cb *pos = NULL;
 390         struct mei_cl_cb *next = NULL;
 391         int status;
 392
 393         if (!dev)
 394                 return;
 395
 396         dev->iamthif_msg_buf_size = 0;
 397         dev->iamthif_msg_buf_index = 0;
 398         dev->iamthif_canceled = false;
 399         dev->iamthif_ioctl = true;
 400         dev->iamthif_state = MEI_IAMTHIF_IDLE;
 401         dev->iamthif_timer = 0;
 402         dev->iamthif_file_object = NULL;
 403
 404         dev_dbg(&dev->pdev->dev, "complete amthif cmd_list cb.\n");
 405
 406         list_for_each_entry_safe(pos, next, &dev->amthif_cmd_list.list, list) {
 407                 list_del(&pos->list);
 408
 409                 if (pos->cl && pos->cl == &dev->iamthif_cl) {
 410                         status = mei_amthif_send_cmd(dev, pos);
 411                         if (status) {
 412                                 dev_dbg(&dev->pdev->dev,
 413                                         "amthif write failed status = %d\n",
 414                                                 status);
 415                                 return;
 416                         }
 417                         break;
 418                 }
 419         }
 420 }
 421
 422
 423 unsigned int mei_amthif_poll(struct mei_device *dev,
 424                 struct file *file, poll_table *wait)
 425 {
 426         unsigned int mask = 0;
 427
 428         poll_wait(file, &dev->iamthif_cl.wait, wait);
 429
 430         mutex_lock(&dev->device_lock);
 431         if (!mei_cl_is_connected(&dev->iamthif_cl)) {
 432
 433                 mask = POLLERR;
 434
 435         } else if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE &&
 436                    dev->iamthif_file_object == file) {
 437
 438                 mask |= (POLLIN | POLLRDNORM);
 439                 dev_dbg(&dev->pdev->dev, "run next amthif cb\n");
 440                 mei_amthif_run_next_cmd(dev);
 441         }
 442         mutex_unlock(&dev->device_lock);
 443
 444         return mask;
 445 }
 446
 447
 448
 449 /**
 450  * mei_amthif_irq_write_completed - processes completed iamthif operation.
 451  *
 452  * @dev: the device structure.
 453  * @slots: free slots.
 454  * @cb_pos: callback block.
 455  * @cl: private data of the file object.
 456  * @cmpl_list: complete list.
 457  *
 458  * returns 0, OK; otherwise, error.
 459  */
 460 int mei_amthif_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
 461                                   s32 *slots, struct mei_cl_cb *cmpl_list)
 462 {
 463         struct mei_device *dev = cl->dev;
 464         struct mei_msg_hdr mei_hdr;
 465         size_t len = dev->iamthif_msg_buf_size - dev->iamthif_msg_buf_index;
 466         u32 msg_slots = mei_data2slots(len);
 467         int rets;
 468
 469         rets = mei_cl_flow_ctrl_creds(cl);
 470         if (rets < 0)
 471                 return rets;
 472
 473         if (rets == 0) {
 474                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
 475                 return 0;
 476         }
 477
 478         mei_hdr.host_addr = cl->host_client_id;
 479         mei_hdr.me_addr = cl->me_client_id;
 480         mei_hdr.reserved = 0;
 481         mei_hdr.internal = 0;
 482
 483         if (*slots >= msg_slots) {
 484                 mei_hdr.length = len;
 485                 mei_hdr.msg_complete = 1;
 486         /* Split the message only if we can write the whole host buffer */
 487         } else if (*slots == dev->hbuf_depth) {
 488                 msg_slots = *slots;
 489                 len = (*slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
 490                 mei_hdr.length = len;
 491                 mei_hdr.msg_complete = 0;
 492         } else {
 493                 /* wait for next time the host buffer is empty */
 494                 return 0;
 495         }
 496
 497         dev_dbg(&dev->pdev->dev, MEI_HDR_FMT,  MEI_HDR_PRM(&mei_hdr));
 498
 499         *slots -=  msg_slots;
 500         rets = mei_write_message(dev, &mei_hdr,
 501                         dev->iamthif_msg_buf + dev->iamthif_msg_buf_index);
 502         if (rets) {
 503                 dev->iamthif_state = MEI_IAMTHIF_IDLE;
 504                 cl->status = rets;
 505                 list_del(&cb->list);
 506                 return rets;
 507         }
 508
 509         if (mei_cl_flow_ctrl_reduce(cl))
 510                 return -EIO;
 511
 512         dev->iamthif_msg_buf_index += mei_hdr.length;
 513         cl->status = 0;
 514
 515         if (mei_hdr.msg_complete) {
 516                 dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
 517                 dev->iamthif_flow_control_pending = true;
 518
 519                 /* save iamthif cb sent to amthif client */
 520                 cb->buf_idx = dev->iamthif_msg_buf_index;
 521                 dev->iamthif_current_cb = cb;
 522
 523                 list_move_tail(&cb->list, &dev->write_waiting_list.list);
 524         }
 525
 526
 527         return 0;
 528 }
 529
 530 /**
 531  * mei_amthif_irq_read_message - read routine after ISR to
 532  *                      handle the read amthif message
 533  *
 534  * @dev: the device structure
 535  * @mei_hdr: header of amthif message
 536  * @complete_list: An instance of our list structure
 537  *
 538  * returns 0 on success, <0 on failure.
 539  */
 540 int mei_amthif_irq_read_msg(struct mei_device *dev,
 541                             struct mei_msg_hdr *mei_hdr,
 542                             struct mei_cl_cb *complete_list)
 543 {
 544         struct mei_cl_cb *cb;
 545         unsigned char *buffer;
 546
 547         BUG_ON(mei_hdr->me_addr != dev->iamthif_cl.me_client_id);
 548         BUG_ON(dev->iamthif_state != MEI_IAMTHIF_READING);
 549
 550         buffer = dev->iamthif_msg_buf + dev->iamthif_msg_buf_index;
 551         BUG_ON(dev->iamthif_mtu < dev->iamthif_msg_buf_index + mei_hdr->length);
 552
 553         mei_read_slots(dev, buffer, mei_hdr->length);
 554
 555         dev->iamthif_msg_buf_index += mei_hdr->length;
 556
 557         if (!mei_hdr->msg_complete)
 558                 return 0;
 559
 560         dev_dbg(&dev->pdev->dev, "amthif_message_buffer_index =%d\n",
 561                         mei_hdr->length);
 562
 563         dev_dbg(&dev->pdev->dev, "completed amthif read.\n ");
 564         if (!dev->iamthif_current_cb)
 565                 return -ENODEV;
 566
 567         cb = dev->iamthif_current_cb;
 568         dev->iamthif_current_cb = NULL;
 569
 570         if (!cb->cl)
 571                 return -ENODEV;
 572
 573         dev->iamthif_stall_timer = 0;
 574         cb->buf_idx = dev->iamthif_msg_buf_index;
 575         cb->read_time = jiffies;
 576         if (dev->iamthif_ioctl && cb->cl == &dev->iamthif_cl) {
 577                 /* found the iamthif cb */
 578                 dev_dbg(&dev->pdev->dev, "complete the amthif read cb.\n ");
 579                 dev_dbg(&dev->pdev->dev, "add the amthif read cb to complete.\n ");
 580                 list_add_tail(&cb->list, &complete_list->list);
 581         }
 582         return 0;
 583 }
 584
 585 /**
 586  * mei_amthif_irq_read - prepares to read amthif data.
 587  *
 588  * @dev: the device structure.
 589  * @slots: free slots.
 590  *
 591  * returns 0, OK; otherwise, error.
 592  */
 593 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots)
 594 {
 595         u32 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
 596
 597         if (*slots < msg_slots)
 598                 return -EMSGSIZE;
 599
 600         *slots -= msg_slots;
 601
 602         if (mei_hbm_cl_flow_control_req(dev, &dev->iamthif_cl)) {
 603                 dev_dbg(&dev->pdev->dev, "iamthif flow control failed\n");
 604                 return -EIO;
 605         }
 606
 607         dev_dbg(&dev->pdev->dev, "iamthif flow control success\n");
 608         dev->iamthif_state = MEI_IAMTHIF_READING;
 609         dev->iamthif_flow_control_pending = false;
 610         dev->iamthif_msg_buf_index = 0;
 611         dev->iamthif_msg_buf_size = 0;
 612         dev->iamthif_stall_timer = MEI_IAMTHIF_STALL_TIMER;
 613         dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
 614         return 0;
 615 }
 616
 617 /**
 618  * mei_amthif_complete - complete amthif callback.
 619  *
 620  * @dev: the device structure.
 621  * @cb_pos: callback block.
 622  */
 623 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb)
 624 {
 625         if (dev->iamthif_canceled != 1) {
 626                 dev->iamthif_state = MEI_IAMTHIF_READ_COMPLETE;
 627                 dev->iamthif_stall_timer = 0;
 628                 memcpy(cb->response_buffer.data,
 629                                 dev->iamthif_msg_buf,
 630                                 dev->iamthif_msg_buf_index);
 631                 list_add_tail(&cb->list, &dev->amthif_rd_complete_list.list);
 632                 dev_dbg(&dev->pdev->dev, "amthif read completed\n");
 633                 dev->iamthif_timer = jiffies;
 634                 dev_dbg(&dev->pdev->dev, "dev->iamthif_timer = %ld\n",
 635                                 dev->iamthif_timer);
 636         } else {
 637                 mei_amthif_run_next_cmd(dev);
 638         }
 639
 640         dev_dbg(&dev->pdev->dev, "completing amthif call back.\n");
 641         wake_up_interruptible(&dev->iamthif_cl.wait);
 642 }
 643
 644 /**
 645  * mei_clear_list - removes all callbacks associated with file
 646  *              from mei_cb_list
 647  *
 648  * @dev: device structure.
 649  * @file: file structure
 650  * @mei_cb_list: callbacks list
 651  *
 652  * mei_clear_list is called to clear resources associated with file
 653  * when application calls close function or Ctrl-C was pressed
 654  *
 655  * returns true if callback removed from the list, false otherwise
 656  */
 657 static bool mei_clear_list(struct mei_device *dev,
 658                 const struct file *file, struct list_head *mei_cb_list)
 659 {
 660         struct mei_cl_cb *cb_pos = NULL;
 661         struct mei_cl_cb *cb_next = NULL;
 662         bool removed = false;
 663
 664         /* list all list member */
 665         list_for_each_entry_safe(cb_pos, cb_next, mei_cb_list, list) {
 666                 /* check if list member associated with a file */
 667                 if (file == cb_pos->file_object) {
 668                         /* remove member from the list */
 669                         list_del(&cb_pos->list);
 670                         /* check if cb equal to current iamthif cb */
 671                         if (dev->iamthif_current_cb == cb_pos) {
 672                                 dev->iamthif_current_cb = NULL;
 673                                 /* send flow control to iamthif client */
 674                                 mei_hbm_cl_flow_control_req(dev,
 675                                                         &dev->iamthif_cl);
 676                         }
 677                         /* free all allocated buffers */
 678                         mei_io_cb_free(cb_pos);
 679                         cb_pos = NULL;
 680                         removed = true;
 681                 }
 682         }
 683         return removed;
 684 }
 685
 686 /**
 687  * mei_clear_lists - removes all callbacks associated with file
 688  *
 689  * @dev: device structure
 690  * @file: file structure
 691  *
 692  * mei_clear_lists is called to clear resources associated with file
 693  * when application calls close function or Ctrl-C was pressed
 694  *
 695  * returns true if callback removed from the list, false otherwise
 696  */
 697 static bool mei_clear_lists(struct mei_device *dev, struct file *file)
 698 {
 699         bool removed = false;
 700
 701         /* remove callbacks associated with a file */
 702         mei_clear_list(dev, file, &dev->amthif_cmd_list.list);
 703         if (mei_clear_list(dev, file, &dev->amthif_rd_complete_list.list))
 704                 removed = true;
 705
 706         mei_clear_list(dev, file, &dev->ctrl_rd_list.list);
 707
 708         if (mei_clear_list(dev, file, &dev->ctrl_wr_list.list))
 709                 removed = true;
 710
 711         if (mei_clear_list(dev, file, &dev->write_waiting_list.list))
 712                 removed = true;
 713
 714         if (mei_clear_list(dev, file, &dev->write_list.list))
 715                 removed = true;
 716
 717         /* check if iamthif_current_cb not NULL */
 718         if (dev->iamthif_current_cb && !removed) {
 719                 /* check file and iamthif current cb association */
 720                 if (dev->iamthif_current_cb->file_object == file) {
 721                         /* remove cb */
 722                         mei_io_cb_free(dev->iamthif_current_cb);
 723                         dev->iamthif_current_cb = NULL;
 724                         removed = true;
 725                 }
 726         }
 727         return removed;
 728 }
 729
 730 /**
 731 * mei_amthif_release - the release function
 732 *
 733 *  @dev: device structure
 734 *  @file: pointer to file structure
 735 *
 736 *  returns 0 on success, <0 on error
 737 */
 738 int mei_amthif_release(struct mei_device *dev, struct file *file)
 739 {
 740         if (dev->iamthif_open_count > 0)
 741                 dev->iamthif_open_count--;
 742
 743         if (dev->iamthif_file_object == file &&
 744             dev->iamthif_state != MEI_IAMTHIF_IDLE) {
 745
 746                 dev_dbg(&dev->pdev->dev, "amthif canceled iamthif state %d\n",
 747                     dev->iamthif_state);
 748                 dev->iamthif_canceled = true;
 749                 if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE) {
 750                         dev_dbg(&dev->pdev->dev, "run next amthif iamthif cb\n");
 751                         mei_amthif_run_next_cmd(dev);
 752                 }
 753         }
 754
 755         if (mei_clear_lists(dev, file))
 756                 dev->iamthif_state = MEI_IAMTHIF_IDLE;
 757
 758         return 0;
 759 }