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