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         mutex_unlock(&dev->device_lock);
 423         poll_wait(file, &dev->iamthif_cl.wait, wait);
 424         mutex_lock(&dev->device_lock);
 425         if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE &&
 426                 dev->iamthif_file_object == file) {
 427                 mask |= (POLLIN | POLLRDNORM);
 428                 dev_dbg(&dev->pdev->dev, "run next amthif cb\n");
 429                 mei_amthif_run_next_cmd(dev);
 430         }
 431         return mask;
 432 }
 433
 434
 435
 436 /**
 437  * mei_amthif_irq_write_completed - processes completed iamthif operation.
 438  *
 439  * @dev: the device structure.
 440  * @slots: free slots.
 441  * @cb_pos: callback block.
 442  * @cl: private data of the file object.
 443  * @cmpl_list: complete list.
 444  *
 445  * returns 0, OK; otherwise, error.
 446  */
 447 int mei_amthif_irq_write_complete(struct mei_device *dev, s32 *slots,
 448                         struct mei_cl_cb *cb, struct mei_cl_cb *cmpl_list)
 449 {
 450         struct mei_msg_hdr mei_hdr;
 451         struct mei_cl *cl = cb->cl;
 452         size_t len = dev->iamthif_msg_buf_size - dev->iamthif_msg_buf_index;
 453         u32 msg_slots = mei_data2slots(len);
 454
 455         mei_hdr.host_addr = cl->host_client_id;
 456         mei_hdr.me_addr = cl->me_client_id;
 457         mei_hdr.reserved = 0;
 458
 459         if (*slots >= msg_slots) {
 460                 mei_hdr.length = len;
 461                 mei_hdr.msg_complete = 1;
 462         /* Split the message only if we can write the whole host buffer */
 463         } else if (*slots == dev->hbuf_depth) {
 464                 msg_slots = *slots;
 465                 len = (*slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
 466                 mei_hdr.length = len;
 467                 mei_hdr.msg_complete = 0;
 468         } else {
 469                 /* wait for next time the host buffer is empty */
 470                 return 0;
 471         }
 472
 473         dev_dbg(&dev->pdev->dev, MEI_HDR_FMT,  MEI_HDR_PRM(&mei_hdr));
 474
 475         *slots -=  msg_slots;
 476         if (mei_write_message(dev, &mei_hdr,
 477                 dev->iamthif_msg_buf + dev->iamthif_msg_buf_index)) {
 478                         dev->iamthif_state = MEI_IAMTHIF_IDLE;
 479                         cl->status = -ENODEV;
 480                         list_del(&cb->list);
 481                         return -ENODEV;
 482         }
 483
 484         if (mei_cl_flow_ctrl_reduce(cl))
 485                 return -ENODEV;
 486
 487         dev->iamthif_msg_buf_index += mei_hdr.length;
 488         cl->status = 0;
 489
 490         if (mei_hdr.msg_complete) {
 491                 dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
 492                 dev->iamthif_flow_control_pending = true;
 493
 494                 /* save iamthif cb sent to amthif client */
 495                 cb->buf_idx = dev->iamthif_msg_buf_index;
 496                 dev->iamthif_current_cb = cb;
 497
 498                 list_move_tail(&cb->list, &dev->write_waiting_list.list);
 499         }
 500
 501
 502         return 0;
 503 }
 504
 505 /**
 506  * mei_amthif_irq_read_message - read routine after ISR to
 507  *                      handle the read amthif message
 508  *
 509  * @dev: the device structure
 510  * @mei_hdr: header of amthif message
 511  * @complete_list: An instance of our list structure
 512  *
 513  * returns 0 on success, <0 on failure.
 514  */
 515 int mei_amthif_irq_read_msg(struct mei_device *dev,
 516                             struct mei_msg_hdr *mei_hdr,
 517                             struct mei_cl_cb *complete_list)
 518 {
 519         struct mei_cl_cb *cb;
 520         unsigned char *buffer;
 521
 522         BUG_ON(mei_hdr->me_addr != dev->iamthif_cl.me_client_id);
 523         BUG_ON(dev->iamthif_state != MEI_IAMTHIF_READING);
 524
 525         buffer = dev->iamthif_msg_buf + dev->iamthif_msg_buf_index;
 526         BUG_ON(dev->iamthif_mtu < dev->iamthif_msg_buf_index + mei_hdr->length);
 527
 528         mei_read_slots(dev, buffer, mei_hdr->length);
 529
 530         dev->iamthif_msg_buf_index += mei_hdr->length;
 531
 532         if (!mei_hdr->msg_complete)
 533                 return 0;
 534
 535         dev_dbg(&dev->pdev->dev, "amthif_message_buffer_index =%d\n",
 536                         mei_hdr->length);
 537
 538         dev_dbg(&dev->pdev->dev, "completed amthif read.\n ");
 539         if (!dev->iamthif_current_cb)
 540                 return -ENODEV;
 541
 542         cb = dev->iamthif_current_cb;
 543         dev->iamthif_current_cb = NULL;
 544
 545         if (!cb->cl)
 546                 return -ENODEV;
 547
 548         dev->iamthif_stall_timer = 0;
 549         cb->buf_idx = dev->iamthif_msg_buf_index;
 550         cb->read_time = jiffies;
 551         if (dev->iamthif_ioctl && cb->cl == &dev->iamthif_cl) {
 552                 /* found the iamthif cb */
 553                 dev_dbg(&dev->pdev->dev, "complete the amthif read cb.\n ");
 554                 dev_dbg(&dev->pdev->dev, "add the amthif read cb to complete.\n ");
 555                 list_add_tail(&cb->list, &complete_list->list);
 556         }
 557         return 0;
 558 }
 559
 560 /**
 561  * mei_amthif_irq_read - prepares to read amthif data.
 562  *
 563  * @dev: the device structure.
 564  * @slots: free slots.
 565  *
 566  * returns 0, OK; otherwise, error.
 567  */
 568 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots)
 569 {
 570         u32 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
 571
 572         if (*slots < msg_slots)
 573                 return -EMSGSIZE;
 574
 575         *slots -= msg_slots;
 576
 577         if (mei_hbm_cl_flow_control_req(dev, &dev->iamthif_cl)) {
 578                 dev_dbg(&dev->pdev->dev, "iamthif flow control failed\n");
 579                 return -EIO;
 580         }
 581
 582         dev_dbg(&dev->pdev->dev, "iamthif flow control success\n");
 583         dev->iamthif_state = MEI_IAMTHIF_READING;
 584         dev->iamthif_flow_control_pending = false;
 585         dev->iamthif_msg_buf_index = 0;
 586         dev->iamthif_msg_buf_size = 0;
 587         dev->iamthif_stall_timer = MEI_IAMTHIF_STALL_TIMER;
 588         dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
 589         return 0;
 590 }
 591
 592 /**
 593  * mei_amthif_complete - complete amthif callback.
 594  *
 595  * @dev: the device structure.
 596  * @cb_pos: callback block.
 597  */
 598 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb)
 599 {
 600         if (dev->iamthif_canceled != 1) {
 601                 dev->iamthif_state = MEI_IAMTHIF_READ_COMPLETE;
 602                 dev->iamthif_stall_timer = 0;
 603                 memcpy(cb->response_buffer.data,
 604                                 dev->iamthif_msg_buf,
 605                                 dev->iamthif_msg_buf_index);
 606                 list_add_tail(&cb->list, &dev->amthif_rd_complete_list.list);
 607                 dev_dbg(&dev->pdev->dev, "amthif read completed\n");
 608                 dev->iamthif_timer = jiffies;
 609                 dev_dbg(&dev->pdev->dev, "dev->iamthif_timer = %ld\n",
 610                                 dev->iamthif_timer);
 611         } else {
 612                 mei_amthif_run_next_cmd(dev);
 613         }
 614
 615         dev_dbg(&dev->pdev->dev, "completing amthif call back.\n");
 616         wake_up_interruptible(&dev->iamthif_cl.wait);
 617 }
 618
 619 /**
 620  * mei_clear_list - removes all callbacks associated with file
 621  *              from mei_cb_list
 622  *
 623  * @dev: device structure.
 624  * @file: file structure
 625  * @mei_cb_list: callbacks list
 626  *
 627  * mei_clear_list is called to clear resources associated with file
 628  * when application calls close function or Ctrl-C was pressed
 629  *
 630  * returns true if callback removed from the list, false otherwise
 631  */
 632 static bool mei_clear_list(struct mei_device *dev,
 633                 const struct file *file, struct list_head *mei_cb_list)
 634 {
 635         struct mei_cl_cb *cb_pos = NULL;
 636         struct mei_cl_cb *cb_next = NULL;
 637         bool removed = false;
 638
 639         /* list all list member */
 640         list_for_each_entry_safe(cb_pos, cb_next, mei_cb_list, list) {
 641                 /* check if list member associated with a file */
 642                 if (file == cb_pos->file_object) {
 643                         /* remove member from the list */
 644                         list_del(&cb_pos->list);
 645                         /* check if cb equal to current iamthif cb */
 646                         if (dev->iamthif_current_cb == cb_pos) {
 647                                 dev->iamthif_current_cb = NULL;
 648                                 /* send flow control to iamthif client */
 649                                 mei_hbm_cl_flow_control_req(dev,
 650                                                         &dev->iamthif_cl);
 651                         }
 652                         /* free all allocated buffers */
 653                         mei_io_cb_free(cb_pos);
 654                         cb_pos = NULL;
 655                         removed = true;
 656                 }
 657         }
 658         return removed;
 659 }
 660
 661 /**
 662  * mei_clear_lists - removes all callbacks associated with file
 663  *
 664  * @dev: device structure
 665  * @file: file structure
 666  *
 667  * mei_clear_lists is called to clear resources associated with file
 668  * when application calls close function or Ctrl-C was pressed
 669  *
 670  * returns true if callback removed from the list, false otherwise
 671  */
 672 static bool mei_clear_lists(struct mei_device *dev, struct file *file)
 673 {
 674         bool removed = false;
 675
 676         /* remove callbacks associated with a file */
 677         mei_clear_list(dev, file, &dev->amthif_cmd_list.list);
 678         if (mei_clear_list(dev, file, &dev->amthif_rd_complete_list.list))
 679                 removed = true;
 680
 681         mei_clear_list(dev, file, &dev->ctrl_rd_list.list);
 682
 683         if (mei_clear_list(dev, file, &dev->ctrl_wr_list.list))
 684                 removed = true;
 685
 686         if (mei_clear_list(dev, file, &dev->write_waiting_list.list))
 687                 removed = true;
 688
 689         if (mei_clear_list(dev, file, &dev->write_list.list))
 690                 removed = true;
 691
 692         /* check if iamthif_current_cb not NULL */
 693         if (dev->iamthif_current_cb && !removed) {
 694                 /* check file and iamthif current cb association */
 695                 if (dev->iamthif_current_cb->file_object == file) {
 696                         /* remove cb */
 697                         mei_io_cb_free(dev->iamthif_current_cb);
 698                         dev->iamthif_current_cb = NULL;
 699                         removed = true;
 700                 }
 701         }
 702         return removed;
 703 }
 704
 705 /**
 706 * mei_amthif_release - the release function
 707 *
 708 *  @dev: device structure
 709 *  @file: pointer to file structure
 710 *
 711 *  returns 0 on success, <0 on error
 712 */
 713 int mei_amthif_release(struct mei_device *dev, struct file *file)
 714 {
 715         if (dev->open_handle_count > 0)
 716                 dev->open_handle_count--;
 717
 718         if (dev->iamthif_file_object == file &&
 719             dev->iamthif_state != MEI_IAMTHIF_IDLE) {
 720
 721                 dev_dbg(&dev->pdev->dev, "amthif canceled iamthif state %d\n",
 722                     dev->iamthif_state);
 723                 dev->iamthif_canceled = true;
 724                 if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE) {
 725                         dev_dbg(&dev->pdev->dev, "run next amthif iamthif cb\n");
 726                         mei_amthif_run_next_cmd(dev);
 727                 }
 728         }
 729
 730         if (mei_clear_lists(dev, file))
 731                 dev->iamthif_state = MEI_IAMTHIF_IDLE;
 732
 733         return 0;
 734 }