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