drivers/misc/mei/client.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/pci.h>
  18 #include <linux/sched.h>
  19 #include <linux/wait.h>
  20 #include <linux/delay.h>
  21
  22 #include <linux/mei.h>
  23
  24 #include "mei_dev.h"
  25 #include "hbm.h"
  26 #include "client.h"
  27
  28 /**
  29  * mei_me_cl_by_uuid - locate index of me client
  30  *
  31  * @dev: mei device
  32  * returns me client index or -ENOENT if not found
  33  */
  34 int mei_me_cl_by_uuid(const struct mei_device *dev, const uuid_le *uuid)
  35 {
  36         int i, res = -ENOENT;
  37
  38         for (i = 0; i < dev->me_clients_num; ++i)
  39                 if (uuid_le_cmp(*uuid,
  40                                 dev->me_clients[i].props.protocol_name) == 0) {
  41                         res = i;
  42                         break;
  43                 }
  44
  45         return res;
  46 }
  47
  48
  49 /**
  50  * mei_me_cl_by_id return index to me_clients for client_id
  51  *
  52  * @dev: the device structure
  53  * @client_id: me client id
  54  *
  55  * Locking: called under "dev->device_lock" lock
  56  *
  57  * returns index on success, -ENOENT on failure.
  58  */
  59
  60 int mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
  61 {
  62         int i;
  63         for (i = 0; i < dev->me_clients_num; i++)
  64                 if (dev->me_clients[i].client_id == client_id)
  65                         break;
  66         if (WARN_ON(dev->me_clients[i].client_id != client_id))
  67                 return -ENOENT;
  68
  69         if (i == dev->me_clients_num)
  70                 return -ENOENT;
  71
  72         return i;
  73 }
  74
  75
  76 /**
  77  * mei_io_list_flush - removes list entry belonging to cl.
  78  *
  79  * @list:  An instance of our list structure
  80  * @cl: host client
  81  */
  82 void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl)
  83 {
  84         struct mei_cl_cb *cb;
  85         struct mei_cl_cb *next;
  86
  87         list_for_each_entry_safe(cb, next, &list->list, list) {
  88                 if (cb->cl && mei_cl_cmp_id(cl, cb->cl))
  89                         list_del(&cb->list);
  90         }
  91 }
  92
  93 /**
  94  * mei_io_cb_free - free mei_cb_private related memory
  95  *
  96  * @cb: mei callback struct
  97  */
  98 void mei_io_cb_free(struct mei_cl_cb *cb)
  99 {
 100         if (cb == NULL)
 101                 return;
 102
 103         kfree(cb->request_buffer.data);
 104         kfree(cb->response_buffer.data);
 105         kfree(cb);
 106 }
 107
 108 /**
 109  * mei_io_cb_init - allocate and initialize io callback
 110  *
 111  * @cl - mei client
 112  * @fp: pointer to file structure
 113  *
 114  * returns mei_cl_cb pointer or NULL;
 115  */
 116 struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, struct file *fp)
 117 {
 118         struct mei_cl_cb *cb;
 119
 120         cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
 121         if (!cb)
 122                 return NULL;
 123
 124         mei_io_list_init(cb);
 125
 126         cb->file_object = fp;
 127         cb->cl = cl;
 128         cb->buf_idx = 0;
 129         return cb;
 130 }
 131
 132 /**
 133  * mei_io_cb_alloc_req_buf - allocate request buffer
 134  *
 135  * @cb: io callback structure
 136  * @length: size of the buffer
 137  *
 138  * returns 0 on success
 139  *         -EINVAL if cb is NULL
 140  *         -ENOMEM if allocation failed
 141  */
 142 int mei_io_cb_alloc_req_buf(struct mei_cl_cb *cb, size_t length)
 143 {
 144         if (!cb)
 145                 return -EINVAL;
 146
 147         if (length == 0)
 148                 return 0;
 149
 150         cb->request_buffer.data = kmalloc(length, GFP_KERNEL);
 151         if (!cb->request_buffer.data)
 152                 return -ENOMEM;
 153         cb->request_buffer.size = length;
 154         return 0;
 155 }
 156 /**
 157  * mei_io_cb_alloc_resp_buf - allocate respose buffer
 158  *
 159  * @cb: io callback structure
 160  * @length: size of the buffer
 161  *
 162  * returns 0 on success
 163  *         -EINVAL if cb is NULL
 164  *         -ENOMEM if allocation failed
 165  */
 166 int mei_io_cb_alloc_resp_buf(struct mei_cl_cb *cb, size_t length)
 167 {
 168         if (!cb)
 169                 return -EINVAL;
 170
 171         if (length == 0)
 172                 return 0;
 173
 174         cb->response_buffer.data = kmalloc(length, GFP_KERNEL);
 175         if (!cb->response_buffer.data)
 176                 return -ENOMEM;
 177         cb->response_buffer.size = length;
 178         return 0;
 179 }
 180
 181
 182
 183 /**
 184  * mei_cl_flush_queues - flushes queue lists belonging to cl.
 185  *
 186  * @cl: host client
 187  */
 188 int mei_cl_flush_queues(struct mei_cl *cl)
 189 {
 190         struct mei_device *dev;
 191
 192         if (WARN_ON(!cl || !cl->dev))
 193                 return -EINVAL;
 194
 195         dev = cl->dev;
 196
 197         cl_dbg(dev, cl, "remove list entry belonging to cl\n");
 198         mei_io_list_flush(&cl->dev->read_list, cl);
 199         mei_io_list_flush(&cl->dev->write_list, cl);
 200         mei_io_list_flush(&cl->dev->write_waiting_list, cl);
 201         mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
 202         mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
 203         mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
 204         mei_io_list_flush(&cl->dev->amthif_rd_complete_list, cl);
 205         return 0;
 206 }
 207
 208
 209 /**
 210  * mei_cl_init - initializes intialize cl.
 211  *
 212  * @cl: host client to be initialized
 213  * @dev: mei device
 214  */
 215 void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
 216 {
 217         memset(cl, 0, sizeof(struct mei_cl));
 218         init_waitqueue_head(&cl->wait);
 219         init_waitqueue_head(&cl->rx_wait);
 220         init_waitqueue_head(&cl->tx_wait);
 221         INIT_LIST_HEAD(&cl->link);
 222         INIT_LIST_HEAD(&cl->device_link);
 223         cl->reading_state = MEI_IDLE;
 224         cl->writing_state = MEI_IDLE;
 225         cl->dev = dev;
 226 }
 227
 228 /**
 229  * mei_cl_allocate - allocates cl  structure and sets it up.
 230  *
 231  * @dev: mei device
 232  * returns  The allocated file or NULL on failure
 233  */
 234 struct mei_cl *mei_cl_allocate(struct mei_device *dev)
 235 {
 236         struct mei_cl *cl;
 237
 238         cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
 239         if (!cl)
 240                 return NULL;
 241
 242         mei_cl_init(cl, dev);
 243
 244         return cl;
 245 }
 246
 247 /**
 248  * mei_cl_find_read_cb - find this cl's callback in the read list
 249  *
 250  * @cl: host client
 251  *
 252  * returns cb on success, NULL on error
 253  */
 254 struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl)
 255 {
 256         struct mei_device *dev = cl->dev;
 257         struct mei_cl_cb *cb = NULL;
 258         struct mei_cl_cb *next = NULL;
 259
 260         list_for_each_entry_safe(cb, next, &dev->read_list.list, list)
 261                 if (mei_cl_cmp_id(cl, cb->cl))
 262                         return cb;
 263         return NULL;
 264 }
 265
 266 /** mei_cl_link: allocte host id in the host map
 267  *
 268  * @cl - host client
 269  * @id - fixed host id or -1 for genereting one
 270  *
 271  * returns 0 on success
 272  *      -EINVAL on incorrect values
 273  *      -ENONET if client not found
 274  */
 275 int mei_cl_link(struct mei_cl *cl, int id)
 276 {
 277         struct mei_device *dev;
 278         long open_handle_count;
 279
 280         if (WARN_ON(!cl || !cl->dev))
 281                 return -EINVAL;
 282
 283         dev = cl->dev;
 284
 285         /* If Id is not asigned get one*/
 286         if (id == MEI_HOST_CLIENT_ID_ANY)
 287                 id = find_first_zero_bit(dev->host_clients_map,
 288                                         MEI_CLIENTS_MAX);
 289
 290         if (id >= MEI_CLIENTS_MAX) {
 291                 dev_err(&dev->pdev->dev, "id exceded %d", MEI_CLIENTS_MAX) ;
 292                 return -EMFILE;
 293         }
 294
 295         open_handle_count = dev->open_handle_count + dev->iamthif_open_count;
 296         if (open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
 297                 dev_err(&dev->pdev->dev, "open_handle_count exceded %d",
 298                         MEI_MAX_OPEN_HANDLE_COUNT);
 299                 return -EMFILE;
 300         }
 301
 302         dev->open_handle_count++;
 303
 304         cl->host_client_id = id;
 305         list_add_tail(&cl->link, &dev->file_list);
 306
 307         set_bit(id, dev->host_clients_map);
 308
 309         cl->state = MEI_FILE_INITIALIZING;
 310
 311         cl_dbg(dev, cl, "link cl\n");
 312         return 0;
 313 }
 314
 315 /**
 316  * mei_cl_unlink - remove me_cl from the list
 317  *
 318  * @cl: host client
 319  */
 320 int mei_cl_unlink(struct mei_cl *cl)
 321 {
 322         struct mei_device *dev;
 323
 324         /* don't shout on error exit path */
 325         if (!cl)
 326                 return 0;
 327
 328         /* wd and amthif might not be initialized */
 329         if (!cl->dev)
 330                 return 0;
 331
 332         dev = cl->dev;
 333
 334         cl_dbg(dev, cl, "unlink client");
 335
 336         if (dev->open_handle_count > 0)
 337                 dev->open_handle_count--;
 338
 339         /* never clear the 0 bit */
 340         if (cl->host_client_id)
 341                 clear_bit(cl->host_client_id, dev->host_clients_map);
 342
 343         list_del_init(&cl->link);
 344
 345         cl->state = MEI_FILE_INITIALIZING;
 346
 347         return 0;
 348 }
 349
 350
 351 void mei_host_client_init(struct work_struct *work)
 352 {
 353         struct mei_device *dev = container_of(work,
 354                                               struct mei_device, init_work);
 355         struct mei_client_properties *client_props;
 356         int i;
 357
 358         mutex_lock(&dev->device_lock);
 359
 360         for (i = 0; i < dev->me_clients_num; i++) {
 361                 client_props = &dev->me_clients[i].props;
 362
 363                 if (!uuid_le_cmp(client_props->protocol_name, mei_amthif_guid))
 364                         mei_amthif_host_init(dev);
 365                 else if (!uuid_le_cmp(client_props->protocol_name, mei_wd_guid))
 366                         mei_wd_host_init(dev);
 367                 else if (!uuid_le_cmp(client_props->protocol_name, mei_nfc_guid))
 368                         mei_nfc_host_init(dev);
 369
 370         }
 371
 372         dev->dev_state = MEI_DEV_ENABLED;
 373
 374         mutex_unlock(&dev->device_lock);
 375 }
 376
 377
 378 /**
 379  * mei_cl_disconnect - disconnect host clinet form the me one
 380  *
 381  * @cl: host client
 382  *
 383  * Locking: called under "dev->device_lock" lock
 384  *
 385  * returns 0 on success, <0 on failure.
 386  */
 387 int mei_cl_disconnect(struct mei_cl *cl)
 388 {
 389         struct mei_device *dev;
 390         struct mei_cl_cb *cb;
 391         int rets, err;
 392
 393         if (WARN_ON(!cl || !cl->dev))
 394                 return -ENODEV;
 395
 396         dev = cl->dev;
 397
 398         cl_dbg(dev, cl, "disconnecting");
 399
 400         if (cl->state != MEI_FILE_DISCONNECTING)
 401                 return 0;
 402
 403         cb = mei_io_cb_init(cl, NULL);
 404         if (!cb)
 405                 return -ENOMEM;
 406
 407         cb->fop_type = MEI_FOP_CLOSE;
 408         if (dev->hbuf_is_ready) {
 409                 dev->hbuf_is_ready = false;
 410                 if (mei_hbm_cl_disconnect_req(dev, cl)) {
 411                         rets = -ENODEV;
 412                         cl_err(dev, cl, "failed to disconnect.\n");
 413                         goto free;
 414                 }
 415                 mdelay(10); /* Wait for hardware disconnection ready */
 416                 list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
 417         } else {
 418                 cl_dbg(dev, cl, "add disconnect cb to control write list\n");
 419                 list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
 420
 421         }
 422         mutex_unlock(&dev->device_lock);
 423
 424         err = wait_event_timeout(dev->wait_recvd_msg,
 425                         MEI_FILE_DISCONNECTED == cl->state,
 426                         mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 427
 428         mutex_lock(&dev->device_lock);
 429         if (MEI_FILE_DISCONNECTED == cl->state) {
 430                 rets = 0;
 431                 cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
 432         } else {
 433                 rets = -ENODEV;
 434                 if (MEI_FILE_DISCONNECTED != cl->state)
 435                         cl_err(dev, cl, "wrong status client disconnect.\n");
 436
 437                 if (err)
 438                         cl_dbg(dev, cl, "wait failed disconnect err=%08x\n",
 439                                         err);
 440
 441                 cl_err(dev, cl, "failed to disconnect from FW client.\n");
 442         }
 443
 444         mei_io_list_flush(&dev->ctrl_rd_list, cl);
 445         mei_io_list_flush(&dev->ctrl_wr_list, cl);
 446 free:
 447         mei_io_cb_free(cb);
 448         return rets;
 449 }
 450
 451
 452 /**
 453  * mei_cl_is_other_connecting - checks if other
 454  *    client with the same me client id is connecting
 455  *
 456  * @cl: private data of the file object
 457  *
 458  * returns ture if other client is connected, 0 - otherwise.
 459  */
 460 bool mei_cl_is_other_connecting(struct mei_cl *cl)
 461 {
 462         struct mei_device *dev;
 463         struct mei_cl *pos;
 464         struct mei_cl *next;
 465
 466         if (WARN_ON(!cl || !cl->dev))
 467                 return false;
 468
 469         dev = cl->dev;
 470
 471         list_for_each_entry_safe(pos, next, &dev->file_list, link) {
 472                 if ((pos->state == MEI_FILE_CONNECTING) &&
 473                     (pos != cl) && cl->me_client_id == pos->me_client_id)
 474                         return true;
 475
 476         }
 477
 478         return false;
 479 }
 480
 481 /**
 482  * mei_cl_connect - connect host clinet to the me one
 483  *
 484  * @cl: host client
 485  *
 486  * Locking: called under "dev->device_lock" lock
 487  *
 488  * returns 0 on success, <0 on failure.
 489  */
 490 int mei_cl_connect(struct mei_cl *cl, struct file *file)
 491 {
 492         struct mei_device *dev;
 493         struct mei_cl_cb *cb;
 494         int rets;
 495
 496         if (WARN_ON(!cl || !cl->dev))
 497                 return -ENODEV;
 498
 499         dev = cl->dev;
 500
 501         cb = mei_io_cb_init(cl, file);
 502         if (!cb) {
 503                 rets = -ENOMEM;
 504                 goto out;
 505         }
 506
 507         cb->fop_type = MEI_FOP_IOCTL;
 508
 509         if (dev->hbuf_is_ready && !mei_cl_is_other_connecting(cl)) {
 510                 dev->hbuf_is_ready = false;
 511
 512                 if (mei_hbm_cl_connect_req(dev, cl)) {
 513                         rets = -ENODEV;
 514                         goto out;
 515                 }
 516                 cl->timer_count = MEI_CONNECT_TIMEOUT;
 517                 list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
 518         } else {
 519                 list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
 520         }
 521
 522         mutex_unlock(&dev->device_lock);
 523         rets = wait_event_timeout(dev->wait_recvd_msg,
 524                                  (cl->state == MEI_FILE_CONNECTED ||
 525                                   cl->state == MEI_FILE_DISCONNECTED),
 526                                  mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 527         mutex_lock(&dev->device_lock);
 528
 529         if (cl->state != MEI_FILE_CONNECTED) {
 530                 rets = -EFAULT;
 531
 532                 mei_io_list_flush(&dev->ctrl_rd_list, cl);
 533                 mei_io_list_flush(&dev->ctrl_wr_list, cl);
 534                 goto out;
 535         }
 536
 537         rets = cl->status;
 538
 539 out:
 540         mei_io_cb_free(cb);
 541         return rets;
 542 }
 543
 544 /**
 545  * mei_cl_flow_ctrl_creds - checks flow_control credits for cl.
 546  *
 547  * @cl: private data of the file object
 548  *
 549  * returns 1 if mei_flow_ctrl_creds >0, 0 - otherwise.
 550  *      -ENOENT if mei_cl is not present
 551  *      -EINVAL if single_recv_buf == 0
 552  */
 553 int mei_cl_flow_ctrl_creds(struct mei_cl *cl)
 554 {
 555         struct mei_device *dev;
 556         int i;
 557
 558         if (WARN_ON(!cl || !cl->dev))
 559                 return -EINVAL;
 560
 561         dev = cl->dev;
 562
 563         if (!dev->me_clients_num)
 564                 return 0;
 565
 566         if (cl->mei_flow_ctrl_creds > 0)
 567                 return 1;
 568
 569         for (i = 0; i < dev->me_clients_num; i++) {
 570                 struct mei_me_client  *me_cl = &dev->me_clients[i];
 571                 if (me_cl->client_id == cl->me_client_id) {
 572                         if (me_cl->mei_flow_ctrl_creds) {
 573                                 if (WARN_ON(me_cl->props.single_recv_buf == 0))
 574                                         return -EINVAL;
 575                                 return 1;
 576                         } else {
 577                                 return 0;
 578                         }
 579                 }
 580         }
 581         return -ENOENT;
 582 }
 583
 584 /**
 585  * mei_cl_flow_ctrl_reduce - reduces flow_control.
 586  *
 587  * @cl: private data of the file object
 588  *
 589  * @returns
 590  *      0 on success
 591  *      -ENOENT when me client is not found
 592  *      -EINVAL when ctrl credits are <= 0
 593  */
 594 int mei_cl_flow_ctrl_reduce(struct mei_cl *cl)
 595 {
 596         struct mei_device *dev;
 597         int i;
 598
 599         if (WARN_ON(!cl || !cl->dev))
 600                 return -EINVAL;
 601
 602         dev = cl->dev;
 603
 604         if (!dev->me_clients_num)
 605                 return -ENOENT;
 606
 607         for (i = 0; i < dev->me_clients_num; i++) {
 608                 struct mei_me_client  *me_cl = &dev->me_clients[i];
 609                 if (me_cl->client_id == cl->me_client_id) {
 610                         if (me_cl->props.single_recv_buf != 0) {
 611                                 if (WARN_ON(me_cl->mei_flow_ctrl_creds <= 0))
 612                                         return -EINVAL;
 613                                 dev->me_clients[i].mei_flow_ctrl_creds--;
 614                         } else {
 615                                 if (WARN_ON(cl->mei_flow_ctrl_creds <= 0))
 616                                         return -EINVAL;
 617                                 cl->mei_flow_ctrl_creds--;
 618                         }
 619                         return 0;
 620                 }
 621         }
 622         return -ENOENT;
 623 }
 624
 625 /**
 626  * mei_cl_read_start - the start read client message function.
 627  *
 628  * @cl: host client
 629  *
 630  * returns 0 on success, <0 on failure.
 631  */
 632 int mei_cl_read_start(struct mei_cl *cl, size_t length)
 633 {
 634         struct mei_device *dev;
 635         struct mei_cl_cb *cb;
 636         int rets;
 637         int i;
 638
 639         if (WARN_ON(!cl || !cl->dev))
 640                 return -ENODEV;
 641
 642         dev = cl->dev;
 643
 644         if (!mei_cl_is_connected(cl))
 645                 return -ENODEV;
 646
 647         if (cl->read_cb) {
 648                 cl_dbg(dev, cl, "read is pending.\n");
 649                 return -EBUSY;
 650         }
 651         i = mei_me_cl_by_id(dev, cl->me_client_id);
 652         if (i < 0) {
 653                 cl_err(dev, cl, "no such me client %d\n", cl->me_client_id);
 654                 return  -ENODEV;
 655         }
 656
 657         cb = mei_io_cb_init(cl, NULL);
 658         if (!cb)
 659                 return -ENOMEM;
 660
 661         /* always allocate at least client max message */
 662         length = max_t(size_t, length, dev->me_clients[i].props.max_msg_length);
 663         rets = mei_io_cb_alloc_resp_buf(cb, length);
 664         if (rets)
 665                 goto err;
 666
 667         cb->fop_type = MEI_FOP_READ;
 668         cl->read_cb = cb;
 669         if (dev->hbuf_is_ready) {
 670                 dev->hbuf_is_ready = false;
 671                 if (mei_hbm_cl_flow_control_req(dev, cl)) {
 672                         cl_err(dev, cl, "flow control send failed\n");
 673                         rets = -ENODEV;
 674                         goto err;
 675                 }
 676                 list_add_tail(&cb->list, &dev->read_list.list);
 677         } else {
 678                 list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
 679         }
 680         return rets;
 681 err:
 682         mei_io_cb_free(cb);
 683         return rets;
 684 }
 685
 686 /**
 687  * mei_cl_irq_write_complete - write a message to device
 688  *      from the interrupt thread context
 689  *
 690  * @cl: client
 691  * @cb: callback block.
 692  * @slots: free slots.
 693  * @cmpl_list: complete list.
 694  *
 695  * returns 0, OK; otherwise error.
 696  */
 697 int mei_cl_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
 698                                      s32 *slots, struct mei_cl_cb *cmpl_list)
 699 {
 700         struct mei_device *dev;
 701         struct mei_msg_data *buf;
 702         struct mei_msg_hdr mei_hdr;
 703         size_t len;
 704         u32 msg_slots;
 705         int rets;
 706
 707
 708         if (WARN_ON(!cl || !cl->dev))
 709                 return -ENODEV;
 710
 711         dev = cl->dev;
 712
 713         buf = &cb->request_buffer;
 714
 715         rets = mei_cl_flow_ctrl_creds(cl);
 716         if (rets < 0)
 717                 return rets;
 718
 719         if (rets == 0) {
 720                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
 721                 return 0;
 722         }
 723
 724         len = buf->size - cb->buf_idx;
 725         msg_slots = mei_data2slots(len);
 726
 727         mei_hdr.host_addr = cl->host_client_id;
 728         mei_hdr.me_addr = cl->me_client_id;
 729         mei_hdr.reserved = 0;
 730         mei_hdr.internal = cb->internal;
 731
 732         if (*slots >= msg_slots) {
 733                 mei_hdr.length = len;
 734                 mei_hdr.msg_complete = 1;
 735         /* Split the message only if we can write the whole host buffer */
 736         } else if (*slots == dev->hbuf_depth) {
 737                 msg_slots = *slots;
 738                 len = (*slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
 739                 mei_hdr.length = len;
 740                 mei_hdr.msg_complete = 0;
 741         } else {
 742                 /* wait for next time the host buffer is empty */
 743                 return 0;
 744         }
 745
 746         cl_dbg(dev, cl, "buf: size = %d idx = %lu\n",
 747                         cb->request_buffer.size, cb->buf_idx);
 748
 749         *slots -=  msg_slots;
 750         rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
 751         if (rets) {
 752                 cl->status = rets;
 753                 list_move_tail(&cb->list, &cmpl_list->list);
 754                 return rets;
 755         }
 756
 757         cl->status = 0;
 758         cl->writing_state = MEI_WRITING;
 759         cb->buf_idx += mei_hdr.length;
 760
 761         if (mei_hdr.msg_complete) {
 762                 if (mei_cl_flow_ctrl_reduce(cl))
 763                         return -EIO;
 764                 list_move_tail(&cb->list, &dev->write_waiting_list.list);
 765         }
 766
 767         return 0;
 768 }
 769
 770 /**
 771  * mei_cl_write - submit a write cb to mei device
 772         assumes device_lock is locked
 773  *
 774  * @cl: host client
 775  * @cl: write callback with filled data
 776  *
 777  * returns numbe of bytes sent on success, <0 on failure.
 778  */
 779 int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking)
 780 {
 781         struct mei_device *dev;
 782         struct mei_msg_data *buf;
 783         struct mei_msg_hdr mei_hdr;
 784         int rets;
 785
 786
 787         if (WARN_ON(!cl || !cl->dev))
 788                 return -ENODEV;
 789
 790         if (WARN_ON(!cb))
 791                 return -EINVAL;
 792
 793         dev = cl->dev;
 794
 795
 796         buf = &cb->request_buffer;
 797
 798         cl_dbg(dev, cl, "mei_cl_write %d\n", buf->size);
 799
 800
 801         cb->fop_type = MEI_FOP_WRITE;
 802
 803         rets = mei_cl_flow_ctrl_creds(cl);
 804         if (rets < 0)
 805                 goto err;
 806
 807         /* Host buffer is not ready, we queue the request */
 808         if (rets == 0 || !dev->hbuf_is_ready) {
 809                 cb->buf_idx = 0;
 810                 /* unseting complete will enqueue the cb for write */
 811                 mei_hdr.msg_complete = 0;
 812                 rets = buf->size;
 813                 goto out;
 814         }
 815
 816         dev->hbuf_is_ready = false;
 817
 818         /* Check for a maximum length */
 819         if (buf->size > mei_hbuf_max_len(dev)) {
 820                 mei_hdr.length = mei_hbuf_max_len(dev);
 821                 mei_hdr.msg_complete = 0;
 822         } else {
 823                 mei_hdr.length = buf->size;
 824                 mei_hdr.msg_complete = 1;
 825         }
 826
 827         mei_hdr.host_addr = cl->host_client_id;
 828         mei_hdr.me_addr = cl->me_client_id;
 829         mei_hdr.reserved = 0;
 830         mei_hdr.internal = cb->internal;
 831
 832
 833         rets = mei_write_message(dev, &mei_hdr, buf->data);
 834         if (rets)
 835                 goto err;
 836
 837         cl->writing_state = MEI_WRITING;
 838         cb->buf_idx = mei_hdr.length;
 839
 840         rets = buf->size;
 841 out:
 842         if (mei_hdr.msg_complete) {
 843                 if (mei_cl_flow_ctrl_reduce(cl)) {
 844                         rets = -ENODEV;
 845                         goto err;
 846                 }
 847                 list_add_tail(&cb->list, &dev->write_waiting_list.list);
 848         } else {
 849                 list_add_tail(&cb->list, &dev->write_list.list);
 850         }
 851
 852
 853         if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
 854
 855                 mutex_unlock(&dev->device_lock);
 856                 if (wait_event_interruptible(cl->tx_wait,
 857                         cl->writing_state == MEI_WRITE_COMPLETE)) {
 858                                 if (signal_pending(current))
 859                                         rets = -EINTR;
 860                                 else
 861                                         rets = -ERESTARTSYS;
 862                 }
 863                 mutex_lock(&dev->device_lock);
 864         }
 865 err:
 866         return rets;
 867 }
 868
 869
 870 /**
 871  * mei_cl_complete - processes completed operation for a client
 872  *
 873  * @cl: private data of the file object.
 874  * @cb: callback block.
 875  */
 876 void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
 877 {
 878         if (cb->fop_type == MEI_FOP_WRITE) {
 879                 mei_io_cb_free(cb);
 880                 cb = NULL;
 881                 cl->writing_state = MEI_WRITE_COMPLETE;
 882                 if (waitqueue_active(&cl->tx_wait))
 883                         wake_up_interruptible(&cl->tx_wait);
 884
 885         } else if (cb->fop_type == MEI_FOP_READ &&
 886                         MEI_READING == cl->reading_state) {
 887                 cl->reading_state = MEI_READ_COMPLETE;
 888                 if (waitqueue_active(&cl->rx_wait))
 889                         wake_up_interruptible(&cl->rx_wait);
 890                 else
 891                         mei_cl_bus_rx_event(cl);
 892
 893         }
 894 }
 895
 896
 897 /**
 898  * mei_cl_all_disconnect - disconnect forcefully all connected clients
 899  *
 900  * @dev - mei device
 901  */
 902
 903 void mei_cl_all_disconnect(struct mei_device *dev)
 904 {
 905         struct mei_cl *cl, *next;
 906
 907         list_for_each_entry_safe(cl, next, &dev->file_list, link) {
 908                 cl->state = MEI_FILE_DISCONNECTED;
 909                 cl->mei_flow_ctrl_creds = 0;
 910                 cl->read_cb = NULL;
 911                 cl->timer_count = 0;
 912         }
 913 }
 914
 915
 916 /**
 917  * mei_cl_all_wakeup  - wake up all readers and writers they can be interrupted
 918  *
 919  * @dev  - mei device
 920  */
 921 void mei_cl_all_wakeup(struct mei_device *dev)
 922 {
 923         struct mei_cl *cl, *next;
 924         list_for_each_entry_safe(cl, next, &dev->file_list, link) {
 925                 if (waitqueue_active(&cl->rx_wait)) {
 926                         cl_dbg(dev, cl, "Waking up reading client!\n");
 927                         wake_up_interruptible(&cl->rx_wait);
 928                 }
 929                 if (waitqueue_active(&cl->tx_wait)) {
 930                         cl_dbg(dev, cl, "Waking up writing client!\n");
 931                         wake_up_interruptible(&cl->tx_wait);
 932                 }
 933         }
 934 }
 935
 936 /**
 937  * mei_cl_all_write_clear - clear all pending writes
 938
 939  * @dev - mei device
 940  */
 941 void mei_cl_all_write_clear(struct mei_device *dev)
 942 {
 943         struct mei_cl_cb *cb, *next;
 944
 945         list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
 946                 list_del(&cb->list);
 947                 mei_io_cb_free(cb);
 948         }
 949 }
 950
 951