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