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