drivers/misc/mei/interrupt.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
  18 #include <linux/export.h>
  19 #include <linux/pci.h>
  20 #include <linux/kthread.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/fs.h>
  23 #include <linux/jiffies.h>
  24
  25 #include <linux/mei.h>
  26
  27 #include "mei_dev.h"
  28 #include "hbm.h"
  29 #include "hw-me.h"
  30 #include "client.h"
  31
  32
  33 /**
  34  * mei_irq_compl_handler - dispatch complete handelers
  35  *      for the completed callbacks
  36  *
  37  * @dev - mei device
  38  * @compl_list - list of completed cbs
  39  */
  40 void mei_irq_compl_handler(struct mei_device *dev, struct mei_cl_cb *compl_list)
  41 {
  42         struct mei_cl_cb *cb, *next;
  43         struct mei_cl *cl;
  44
  45         list_for_each_entry_safe(cb, next, &compl_list->list, list) {
  46                 cl = cb->cl;
  47                 list_del(&cb->list);
  48                 if (!cl)
  49                         continue;
  50
  51                 dev_dbg(&dev->pdev->dev, "completing call back.\n");
  52                 if (cl == &dev->iamthif_cl)
  53                         mei_amthif_complete(dev, cb);
  54                 else
  55                         mei_cl_complete(cl, cb);
  56         }
  57 }
  58 EXPORT_SYMBOL_GPL(mei_irq_compl_handler);
  59
  60 /**
  61  * mei_cl_hbm_equal - check if hbm is addressed to the client
  62  *
  63  * @cl: host client
  64  * @mei_hdr: header of mei client message
  65  *
  66  * returns true if matches, false otherwise
  67  */
  68 static inline int mei_cl_hbm_equal(struct mei_cl *cl,
  69                         struct mei_msg_hdr *mei_hdr)
  70 {
  71         return cl->host_client_id == mei_hdr->host_addr &&
  72                 cl->me_client_id == mei_hdr->me_addr;
  73 }
  74 /**
  75  * mei_cl_is_reading - checks if the client
  76                 is the one to read this message
  77  *
  78  * @cl: mei client
  79  * @mei_hdr: header of mei message
  80  *
  81  * returns true on match and false otherwise
  82  */
  83 static bool mei_cl_is_reading(struct mei_cl *cl, struct mei_msg_hdr *mei_hdr)
  84 {
  85         return mei_cl_hbm_equal(cl, mei_hdr) &&
  86                 cl->state == MEI_FILE_CONNECTED &&
  87                 cl->reading_state != MEI_READ_COMPLETE;
  88 }
  89
  90 /**
  91  * mei_irq_read_client_message - process client message
  92  *
  93  * @dev: the device structure
  94  * @mei_hdr: header of mei client message
  95  * @complete_list: An instance of our list structure
  96  *
  97  * returns 0 on success, <0 on failure.
  98  */
  99 static int mei_cl_irq_read_msg(struct mei_device *dev,
 100                                struct mei_msg_hdr *mei_hdr,
 101                                struct mei_cl_cb *complete_list)
 102 {
 103         struct mei_cl *cl;
 104         struct mei_cl_cb *cb, *next;
 105         unsigned char *buffer = NULL;
 106
 107         list_for_each_entry_safe(cb, next, &dev->read_list.list, list) {
 108                 cl = cb->cl;
 109                 if (!cl || !mei_cl_is_reading(cl, mei_hdr))
 110                         continue;
 111
 112                 cl->reading_state = MEI_READING;
 113
 114                 if (cb->response_buffer.size == 0 ||
 115                     cb->response_buffer.data == NULL) {
 116                         dev_err(&dev->pdev->dev, "response buffer is not allocated.\n");
 117                         list_del(&cb->list);
 118                         return -ENOMEM;
 119                 }
 120
 121                 if (cb->response_buffer.size < mei_hdr->length + cb->buf_idx) {
 122                         dev_dbg(&dev->pdev->dev, "message overflow. size %d len %d idx %ld\n",
 123                                 cb->response_buffer.size,
 124                                 mei_hdr->length, cb->buf_idx);
 125                         buffer = krealloc(cb->response_buffer.data,
 126                                           mei_hdr->length + cb->buf_idx,
 127                                           GFP_KERNEL);
 128
 129                         if (!buffer) {
 130                                 dev_err(&dev->pdev->dev, "allocation failed.\n");
 131                                 list_del(&cb->list);
 132                                 return -ENOMEM;
 133                         }
 134                         cb->response_buffer.data = buffer;
 135                         cb->response_buffer.size =
 136                                 mei_hdr->length + cb->buf_idx;
 137                 }
 138
 139                 buffer = cb->response_buffer.data + cb->buf_idx;
 140                 mei_read_slots(dev, buffer, mei_hdr->length);
 141
 142                 cb->buf_idx += mei_hdr->length;
 143                 if (mei_hdr->msg_complete) {
 144                         cl->status = 0;
 145                         list_del(&cb->list);
 146                         dev_dbg(&dev->pdev->dev, "completed read H cl = %d, ME cl = %d, length = %lu\n",
 147                                 cl->host_client_id,
 148                                 cl->me_client_id,
 149                                 cb->buf_idx);
 150                         list_add_tail(&cb->list, &complete_list->list);
 151                 }
 152                 break;
 153         }
 154
 155         dev_dbg(&dev->pdev->dev, "message read\n");
 156         if (!buffer) {
 157                 mei_read_slots(dev, dev->rd_msg_buf, mei_hdr->length);
 158                 dev_dbg(&dev->pdev->dev, "discarding message " MEI_HDR_FMT "\n",
 159                                 MEI_HDR_PRM(mei_hdr));
 160         }
 161
 162         return 0;
 163 }
 164
 165 /**
 166  * mei_cl_irq_close - processes close related operation from
 167  *      interrupt thread context - send disconnect request
 168  *
 169  * @cl: client
 170  * @cb: callback block.
 171  * @slots: free slots.
 172  * @cmpl_list: complete list.
 173  *
 174  * returns 0, OK; otherwise, error.
 175  */
 176 static int mei_cl_irq_close(struct mei_cl *cl, struct mei_cl_cb *cb,
 177                         s32 *slots, struct mei_cl_cb *cmpl_list)
 178 {
 179         struct mei_device *dev = cl->dev;
 180
 181         u32 msg_slots =
 182                 mei_data2slots(sizeof(struct hbm_client_connect_request));
 183
 184         if (*slots < msg_slots)
 185                 return -EMSGSIZE;
 186
 187         *slots -= msg_slots;
 188
 189         if (mei_hbm_cl_disconnect_req(dev, cl)) {
 190                 cl->status = 0;
 191                 cb->buf_idx = 0;
 192                 list_move_tail(&cb->list, &cmpl_list->list);
 193                 return -EIO;
 194         }
 195
 196         cl->state = MEI_FILE_DISCONNECTING;
 197         cl->status = 0;
 198         cb->buf_idx = 0;
 199         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 200         cl->timer_count = MEI_CONNECT_TIMEOUT;
 201
 202         return 0;
 203 }
 204
 205
 206 /**
 207  * mei_cl_irq_close - processes client read related operation from the
 208  *      interrupt thread context - request for flow control credits
 209  *
 210  * @cl: client
 211  * @cb: callback block.
 212  * @slots: free slots.
 213  * @cmpl_list: complete list.
 214  *
 215  * returns 0, OK; otherwise, error.
 216  */
 217 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
 218                            s32 *slots, struct mei_cl_cb *cmpl_list)
 219 {
 220         struct mei_device *dev = cl->dev;
 221
 222         u32 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
 223
 224         if (*slots < msg_slots) {
 225                 /* return the cancel routine */
 226                 list_del(&cb->list);
 227                 return -EMSGSIZE;
 228         }
 229
 230         *slots -= msg_slots;
 231
 232         if (mei_hbm_cl_flow_control_req(dev, cl)) {
 233                 cl->status = -ENODEV;
 234                 cb->buf_idx = 0;
 235                 list_move_tail(&cb->list, &cmpl_list->list);
 236                 return -ENODEV;
 237         }
 238         list_move_tail(&cb->list, &dev->read_list.list);
 239
 240         return 0;
 241 }
 242
 243
 244 /**
 245  * mei_cl_irq_ioctl - processes client ioctl related operation from the
 246  *      interrupt thread context -   send connection request
 247  *
 248  * @cl: client
 249  * @cb: callback block.
 250  * @slots: free slots.
 251  * @cmpl_list: complete list.
 252  *
 253  * returns 0, OK; otherwise, error.
 254  */
 255 static int mei_cl_irq_ioctl(struct mei_cl *cl, struct mei_cl_cb *cb,
 256                            s32 *slots, struct mei_cl_cb *cmpl_list)
 257 {
 258         struct mei_device *dev = cl->dev;
 259
 260         u32 msg_slots =
 261                 mei_data2slots(sizeof(struct hbm_client_connect_request));
 262
 263         if (*slots < msg_slots) {
 264                 /* return the cancel routine */
 265                 list_del(&cb->list);
 266                 return -EMSGSIZE;
 267         }
 268
 269         *slots -=  msg_slots;
 270
 271         cl->state = MEI_FILE_CONNECTING;
 272
 273         if (mei_hbm_cl_connect_req(dev, cl)) {
 274                 cl->status = -ENODEV;
 275                 cb->buf_idx = 0;
 276                 list_del(&cb->list);
 277                 return -ENODEV;
 278         }
 279
 280         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 281         cl->timer_count = MEI_CONNECT_TIMEOUT;
 282         return 0;
 283 }
 284
 285
 286 /**
 287  * mei_irq_read_handler - bottom half read routine after ISR to
 288  * handle the read processing.
 289  *
 290  * @dev: the device structure
 291  * @cmpl_list: An instance of our list structure
 292  * @slots: slots to read.
 293  *
 294  * returns 0 on success, <0 on failure.
 295  */
 296 int mei_irq_read_handler(struct mei_device *dev,
 297                 struct mei_cl_cb *cmpl_list, s32 *slots)
 298 {
 299         struct mei_msg_hdr *mei_hdr;
 300         struct mei_cl *cl_pos = NULL;
 301         struct mei_cl *cl_next = NULL;
 302         int ret = 0;
 303
 304         if (!dev->rd_msg_hdr) {
 305                 dev->rd_msg_hdr = mei_read_hdr(dev);
 306                 dev_dbg(&dev->pdev->dev, "slots =%08x.\n", *slots);
 307                 (*slots)--;
 308                 dev_dbg(&dev->pdev->dev, "slots =%08x.\n", *slots);
 309         }
 310         mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
 311         dev_dbg(&dev->pdev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
 312
 313         if (mei_hdr->reserved || !dev->rd_msg_hdr) {
 314                 dev_dbg(&dev->pdev->dev, "corrupted message header.\n");
 315                 ret = -EBADMSG;
 316                 goto end;
 317         }
 318
 319         if (mei_hdr->host_addr || mei_hdr->me_addr) {
 320                 list_for_each_entry_safe(cl_pos, cl_next,
 321                                         &dev->file_list, link) {
 322                         dev_dbg(&dev->pdev->dev,
 323                                         "list_for_each_entry_safe read host"
 324                                         " client = %d, ME client = %d\n",
 325                                         cl_pos->host_client_id,
 326                                         cl_pos->me_client_id);
 327                         if (mei_cl_hbm_equal(cl_pos, mei_hdr))
 328                                 break;
 329                 }
 330
 331                 if (&cl_pos->link == &dev->file_list) {
 332                         dev_dbg(&dev->pdev->dev, "corrupted message header\n");
 333                         ret = -EBADMSG;
 334                         goto end;
 335                 }
 336         }
 337         if (((*slots) * sizeof(u32)) < mei_hdr->length) {
 338                 dev_err(&dev->pdev->dev,
 339                                 "we can't read the message slots =%08x.\n",
 340                                 *slots);
 341                 /* we can't read the message */
 342                 ret = -ERANGE;
 343                 goto end;
 344         }
 345
 346         /* decide where to read the message too */
 347         if (!mei_hdr->host_addr) {
 348                 dev_dbg(&dev->pdev->dev, "call mei_irq_thread_read_bus_message.\n");
 349                 mei_hbm_dispatch(dev, mei_hdr);
 350                 dev_dbg(&dev->pdev->dev, "end mei_irq_thread_read_bus_message.\n");
 351         } else if (mei_hdr->host_addr == dev->iamthif_cl.host_client_id &&
 352                    (MEI_FILE_CONNECTED == dev->iamthif_cl.state) &&
 353                    (dev->iamthif_state == MEI_IAMTHIF_READING)) {
 354
 355                 dev_dbg(&dev->pdev->dev, "call mei_irq_thread_read_iamthif_message.\n");
 356                 dev_dbg(&dev->pdev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
 357
 358                 ret = mei_amthif_irq_read_msg(dev, mei_hdr, cmpl_list);
 359                 if (ret)
 360                         goto end;
 361         } else {
 362                 dev_dbg(&dev->pdev->dev, "call mei_cl_irq_read_msg.\n");
 363                 dev_dbg(&dev->pdev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
 364                 ret = mei_cl_irq_read_msg(dev, mei_hdr, cmpl_list);
 365                 if (ret)
 366                         goto end;
 367         }
 368
 369         /* reset the number of slots and header */
 370         *slots = mei_count_full_read_slots(dev);
 371         dev->rd_msg_hdr = 0;
 372
 373         if (*slots == -EOVERFLOW) {
 374                 /* overflow - reset */
 375                 dev_err(&dev->pdev->dev, "resetting due to slots overflow.\n");
 376                 /* set the event since message has been read */
 377                 ret = -ERANGE;
 378                 goto end;
 379         }
 380 end:
 381         return ret;
 382 }
 383 EXPORT_SYMBOL_GPL(mei_irq_read_handler);
 384
 385
 386 /**
 387  * mei_irq_write_handler -  dispatch write requests
 388  *  after irq received
 389  *
 390  * @dev: the device structure
 391  * @cmpl_list: An instance of our list structure
 392  *
 393  * returns 0 on success, <0 on failure.
 394  */
 395 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
 396 {
 397
 398         struct mei_cl *cl;
 399         struct mei_cl_cb *cb, *next;
 400         struct mei_cl_cb *list;
 401         s32 slots;
 402         int ret;
 403
 404         if (!mei_hbuf_is_ready(dev)) {
 405                 dev_dbg(&dev->pdev->dev, "host buffer is not empty.\n");
 406                 return 0;
 407         }
 408         slots = mei_hbuf_empty_slots(dev);
 409         if (slots <= 0)
 410                 return -EMSGSIZE;
 411
 412         /* complete all waiting for write CB */
 413         dev_dbg(&dev->pdev->dev, "complete all waiting for write cb.\n");
 414
 415         list = &dev->write_waiting_list;
 416         list_for_each_entry_safe(cb, next, &list->list, list) {
 417                 cl = cb->cl;
 418                 if (cl == NULL)
 419                         continue;
 420
 421                 cl->status = 0;
 422                 list_del(&cb->list);
 423                 if (MEI_WRITING == cl->writing_state &&
 424                     cb->fop_type == MEI_FOP_WRITE &&
 425                     cl != &dev->iamthif_cl) {
 426                         dev_dbg(&dev->pdev->dev, "MEI WRITE COMPLETE\n");
 427                         cl->writing_state = MEI_WRITE_COMPLETE;
 428                         list_add_tail(&cb->list, &cmpl_list->list);
 429                 }
 430                 if (cl == &dev->iamthif_cl) {
 431                         dev_dbg(&dev->pdev->dev, "check iamthif flow control.\n");
 432                         if (dev->iamthif_flow_control_pending) {
 433                                 ret = mei_amthif_irq_read(dev, &slots);
 434                                 if (ret)
 435                                         return ret;
 436                         }
 437                 }
 438         }
 439
 440         if (dev->wd_state == MEI_WD_STOPPING) {
 441                 dev->wd_state = MEI_WD_IDLE;
 442                 wake_up_interruptible(&dev->wait_stop_wd);
 443         }
 444
 445         if (dev->wr_ext_msg.hdr.length) {
 446                 mei_write_message(dev, &dev->wr_ext_msg.hdr,
 447                                 dev->wr_ext_msg.data);
 448                 slots -= mei_data2slots(dev->wr_ext_msg.hdr.length);
 449                 dev->wr_ext_msg.hdr.length = 0;
 450         }
 451         if (dev->dev_state == MEI_DEV_ENABLED) {
 452                 if (dev->wd_pending &&
 453                     mei_cl_flow_ctrl_creds(&dev->wd_cl) > 0) {
 454                         if (mei_wd_send(dev))
 455                                 dev_dbg(&dev->pdev->dev, "wd send failed.\n");
 456                         else if (mei_cl_flow_ctrl_reduce(&dev->wd_cl))
 457                                 return -ENODEV;
 458
 459                         dev->wd_pending = false;
 460
 461                         if (dev->wd_state == MEI_WD_RUNNING)
 462                                 slots -= mei_data2slots(MEI_WD_START_MSG_SIZE);
 463                         else
 464                                 slots -= mei_data2slots(MEI_WD_STOP_MSG_SIZE);
 465                 }
 466         }
 467
 468         /* complete control write list CB */
 469         dev_dbg(&dev->pdev->dev, "complete control write list cb.\n");
 470         list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list.list, list) {
 471                 cl = cb->cl;
 472                 if (!cl) {
 473                         list_del(&cb->list);
 474                         return -ENODEV;
 475                 }
 476                 switch (cb->fop_type) {
 477                 case MEI_FOP_CLOSE:
 478                         /* send disconnect message */
 479                         ret = mei_cl_irq_close(cl, cb, &slots, cmpl_list);
 480                         if (ret)
 481                                 return ret;
 482
 483                         break;
 484                 case MEI_FOP_READ:
 485                         /* send flow control message */
 486                         ret = mei_cl_irq_read(cl, cb, &slots, cmpl_list);
 487                         if (ret)
 488                                 return ret;
 489
 490                         break;
 491                 case MEI_FOP_IOCTL:
 492                         /* connect message */
 493                         if (mei_cl_is_other_connecting(cl))
 494                                 continue;
 495                         ret = mei_cl_irq_ioctl(cl, cb, &slots, cmpl_list);
 496                         if (ret)
 497                                 return ret;
 498
 499                         break;
 500
 501                 default:
 502                         BUG();
 503                 }
 504
 505         }
 506         /* complete  write list CB */
 507         dev_dbg(&dev->pdev->dev, "complete write list cb.\n");
 508         list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
 509                 cl = cb->cl;
 510                 if (cl == NULL)
 511                         continue;
 512                 if (mei_cl_flow_ctrl_creds(cl) <= 0) {
 513                         dev_dbg(&dev->pdev->dev,
 514                                 "No flow control credentials for client %d, not sending.\n",
 515                                 cl->host_client_id);
 516                         continue;
 517                 }
 518
 519                 if (cl == &dev->iamthif_cl)
 520                         ret = mei_amthif_irq_write_complete(cl, cb,
 521                                                 &slots, cmpl_list);
 522                 else
 523                         ret = mei_cl_irq_write_complete(cl, cb,
 524                                                 &slots, cmpl_list);
 525                 if (ret)
 526                         return ret;
 527         }
 528         return 0;
 529 }
 530 EXPORT_SYMBOL_GPL(mei_irq_write_handler);
 531
 532
 533
 534 /**
 535  * mei_timer - timer function.
 536  *
 537  * @work: pointer to the work_struct structure
 538  *
 539  * NOTE: This function is called by timer interrupt work
 540  */
 541 void mei_timer(struct work_struct *work)
 542 {
 543         unsigned long timeout;
 544         struct mei_cl *cl_pos = NULL;
 545         struct mei_cl *cl_next = NULL;
 546         struct mei_cl_cb  *cb_pos = NULL;
 547         struct mei_cl_cb  *cb_next = NULL;
 548
 549         struct mei_device *dev = container_of(work,
 550                                         struct mei_device, timer_work.work);
 551
 552
 553         mutex_lock(&dev->device_lock);
 554         if (dev->dev_state != MEI_DEV_ENABLED) {
 555                 if (dev->dev_state == MEI_DEV_INIT_CLIENTS) {
 556                         if (dev->init_clients_timer) {
 557                                 if (--dev->init_clients_timer == 0) {
 558                                         dev_err(&dev->pdev->dev, "reset: init clients timeout hbm_state = %d.\n",
 559                                                 dev->hbm_state);
 560                                         mei_reset(dev, 1);
 561                                 }
 562                         }
 563                 }
 564                 goto out;
 565         }
 566         /*** connect/disconnect timeouts ***/
 567         list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
 568                 if (cl_pos->timer_count) {
 569                         if (--cl_pos->timer_count == 0) {
 570                                 dev_err(&dev->pdev->dev, "reset: connect/disconnect timeout.\n");
 571                                 mei_reset(dev, 1);
 572                                 goto out;
 573                         }
 574                 }
 575         }
 576
 577         if (dev->iamthif_stall_timer) {
 578                 if (--dev->iamthif_stall_timer == 0) {
 579                         dev_err(&dev->pdev->dev, "reset: amthif  hanged.\n");
 580                         mei_reset(dev, 1);
 581                         dev->iamthif_msg_buf_size = 0;
 582                         dev->iamthif_msg_buf_index = 0;
 583                         dev->iamthif_canceled = false;
 584                         dev->iamthif_ioctl = true;
 585                         dev->iamthif_state = MEI_IAMTHIF_IDLE;
 586                         dev->iamthif_timer = 0;
 587
 588                         mei_io_cb_free(dev->iamthif_current_cb);
 589                         dev->iamthif_current_cb = NULL;
 590
 591                         dev->iamthif_file_object = NULL;
 592                         mei_amthif_run_next_cmd(dev);
 593                 }
 594         }
 595
 596         if (dev->iamthif_timer) {
 597
 598                 timeout = dev->iamthif_timer +
 599                         mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
 600
 601                 dev_dbg(&dev->pdev->dev, "dev->iamthif_timer = %ld\n",
 602                                 dev->iamthif_timer);
 603                 dev_dbg(&dev->pdev->dev, "timeout = %ld\n", timeout);
 604                 dev_dbg(&dev->pdev->dev, "jiffies = %ld\n", jiffies);
 605                 if (time_after(jiffies, timeout)) {
 606                         /*
 607                          * User didn't read the AMTHI data on time (15sec)
 608                          * freeing AMTHI for other requests
 609                          */
 610
 611                         dev_dbg(&dev->pdev->dev, "freeing AMTHI for other requests\n");
 612
 613                         list_for_each_entry_safe(cb_pos, cb_next,
 614                                 &dev->amthif_rd_complete_list.list, list) {
 615
 616                                 cl_pos = cb_pos->file_object->private_data;
 617
 618                                 /* Finding the AMTHI entry. */
 619                                 if (cl_pos == &dev->iamthif_cl)
 620                                         list_del(&cb_pos->list);
 621                         }
 622                         mei_io_cb_free(dev->iamthif_current_cb);
 623                         dev->iamthif_current_cb = NULL;
 624
 625                         dev->iamthif_file_object->private_data = NULL;
 626                         dev->iamthif_file_object = NULL;
 627                         dev->iamthif_timer = 0;
 628                         mei_amthif_run_next_cmd(dev);
 629
 630                 }
 631         }
 632 out:
 633         schedule_delayed_work(&dev->timer_work, 2 * HZ);
 634         mutex_unlock(&dev->device_lock);
 635 }
 636