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/sched.h>
  18 #include <linux/wait.h>
  19 #include <linux/delay.h>
  20 #include <linux/slab.h>
  21 #include <linux/pm_runtime.h>
  22
  23 #include <linux/mei.h>
  24
  25 #include "mei_dev.h"
  26 #include "hbm.h"
  27 #include "client.h"
  28
  29 /**
  30  * mei_me_cl_init - initialize me client
  31  *
  32  * @me_cl: me client
  33  */
  34 void mei_me_cl_init(struct mei_me_client *me_cl)
  35 {
  36         INIT_LIST_HEAD(&me_cl->list);
  37         kref_init(&me_cl->refcnt);
  38 }
  39
  40 /**
  41  * mei_me_cl_get - increases me client refcount
  42  *
  43  * @me_cl: me client
  44  *
  45  * Locking: called under "dev->device_lock" lock
  46  *
  47  * Return: me client or NULL
  48  */
  49 struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl)
  50 {
  51         if (me_cl && kref_get_unless_zero(&me_cl->refcnt))
  52                 return me_cl;
  53
  54         return NULL;
  55 }
  56
  57 /**
  58  * mei_me_cl_release - free me client
  59  *
  60  * Locking: called under "dev->device_lock" lock
  61  *
  62  * @ref: me_client refcount
  63  */
  64 static void mei_me_cl_release(struct kref *ref)
  65 {
  66         struct mei_me_client *me_cl =
  67                 container_of(ref, struct mei_me_client, refcnt);
  68
  69         kfree(me_cl);
  70 }
  71
  72 /**
  73  * mei_me_cl_put - decrease me client refcount and free client if necessary
  74  *
  75  * Locking: called under "dev->device_lock" lock
  76  *
  77  * @me_cl: me client
  78  */
  79 void mei_me_cl_put(struct mei_me_client *me_cl)
  80 {
  81         if (me_cl)
  82                 kref_put(&me_cl->refcnt, mei_me_cl_release);
  83 }
  84
  85 /**
  86  * __mei_me_cl_del  - delete me client from the list and decrease
  87  *     reference counter
  88  *
  89  * @dev: mei device
  90  * @me_cl: me client
  91  *
  92  * Locking: dev->me_clients_rwsem
  93  */
  94 static void __mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
  95 {
  96         if (!me_cl)
  97                 return;
  98
  99         list_del_init(&me_cl->list);
 100         mei_me_cl_put(me_cl);
 101 }
 102
 103 /**
 104  * mei_me_cl_del - delete me client from the list and decrease
 105  *     reference counter
 106  *
 107  * @dev: mei device
 108  * @me_cl: me client
 109  */
 110 void mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
 111 {
 112         down_write(&dev->me_clients_rwsem);
 113         __mei_me_cl_del(dev, me_cl);
 114         up_write(&dev->me_clients_rwsem);
 115 }
 116
 117 /**
 118  * mei_me_cl_add - add me client to the list
 119  *
 120  * @dev: mei device
 121  * @me_cl: me client
 122  */
 123 void mei_me_cl_add(struct mei_device *dev, struct mei_me_client *me_cl)
 124 {
 125         down_write(&dev->me_clients_rwsem);
 126         list_add(&me_cl->list, &dev->me_clients);
 127         up_write(&dev->me_clients_rwsem);
 128 }
 129
 130 /**
 131  * __mei_me_cl_by_uuid - locate me client by uuid
 132  *      increases ref count
 133  *
 134  * @dev: mei device
 135  * @uuid: me client uuid
 136  *
 137  * Return: me client or NULL if not found
 138  *
 139  * Locking: dev->me_clients_rwsem
 140  */
 141 static struct mei_me_client *__mei_me_cl_by_uuid(struct mei_device *dev,
 142                                         const uuid_le *uuid)
 143 {
 144         struct mei_me_client *me_cl;
 145         const uuid_le *pn;
 146
 147         WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
 148
 149         list_for_each_entry(me_cl, &dev->me_clients, list) {
 150                 pn = &me_cl->props.protocol_name;
 151                 if (uuid_le_cmp(*uuid, *pn) == 0)
 152                         return mei_me_cl_get(me_cl);
 153         }
 154
 155         return NULL;
 156 }
 157
 158 /**
 159  * mei_me_cl_by_uuid - locate me client by uuid
 160  *      increases ref count
 161  *
 162  * @dev: mei device
 163  * @uuid: me client uuid
 164  *
 165  * Return: me client or NULL if not found
 166  *
 167  * Locking: dev->me_clients_rwsem
 168  */
 169 struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev,
 170                                         const uuid_le *uuid)
 171 {
 172         struct mei_me_client *me_cl;
 173
 174         down_read(&dev->me_clients_rwsem);
 175         me_cl = __mei_me_cl_by_uuid(dev, uuid);
 176         up_read(&dev->me_clients_rwsem);
 177
 178         return me_cl;
 179 }
 180
 181 /**
 182  * mei_me_cl_by_id - locate me client by client id
 183  *      increases ref count
 184  *
 185  * @dev: the device structure
 186  * @client_id: me client id
 187  *
 188  * Return: me client or NULL if not found
 189  *
 190  * Locking: dev->me_clients_rwsem
 191  */
 192 struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
 193 {
 194
 195         struct mei_me_client *__me_cl, *me_cl = NULL;
 196
 197         down_read(&dev->me_clients_rwsem);
 198         list_for_each_entry(__me_cl, &dev->me_clients, list) {
 199                 if (__me_cl->client_id == client_id) {
 200                         me_cl = mei_me_cl_get(__me_cl);
 201                         break;
 202                 }
 203         }
 204         up_read(&dev->me_clients_rwsem);
 205
 206         return me_cl;
 207 }
 208
 209 /**
 210  * __mei_me_cl_by_uuid_id - locate me client by client id and uuid
 211  *      increases ref count
 212  *
 213  * @dev: the device structure
 214  * @uuid: me client uuid
 215  * @client_id: me client id
 216  *
 217  * Return: me client or null if not found
 218  *
 219  * Locking: dev->me_clients_rwsem
 220  */
 221 static struct mei_me_client *__mei_me_cl_by_uuid_id(struct mei_device *dev,
 222                                            const uuid_le *uuid, u8 client_id)
 223 {
 224         struct mei_me_client *me_cl;
 225         const uuid_le *pn;
 226
 227         WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
 228
 229         list_for_each_entry(me_cl, &dev->me_clients, list) {
 230                 pn = &me_cl->props.protocol_name;
 231                 if (uuid_le_cmp(*uuid, *pn) == 0 &&
 232                     me_cl->client_id == client_id)
 233                         return mei_me_cl_get(me_cl);
 234         }
 235
 236         return NULL;
 237 }
 238
 239
 240 /**
 241  * mei_me_cl_by_uuid_id - locate me client by client id and uuid
 242  *      increases ref count
 243  *
 244  * @dev: the device structure
 245  * @uuid: me client uuid
 246  * @client_id: me client id
 247  *
 248  * Return: me client or null if not found
 249  */
 250 struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
 251                                            const uuid_le *uuid, u8 client_id)
 252 {
 253         struct mei_me_client *me_cl;
 254
 255         down_read(&dev->me_clients_rwsem);
 256         me_cl = __mei_me_cl_by_uuid_id(dev, uuid, client_id);
 257         up_read(&dev->me_clients_rwsem);
 258
 259         return me_cl;
 260 }
 261
 262 /**
 263  * mei_me_cl_rm_by_uuid - remove all me clients matching uuid
 264  *
 265  * @dev: the device structure
 266  * @uuid: me client uuid
 267  *
 268  * Locking: called under "dev->device_lock" lock
 269  */
 270 void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid)
 271 {
 272         struct mei_me_client *me_cl;
 273
 274         dev_dbg(dev->dev, "remove %pUl\n", uuid);
 275
 276         down_write(&dev->me_clients_rwsem);
 277         me_cl = __mei_me_cl_by_uuid(dev, uuid);
 278         __mei_me_cl_del(dev, me_cl);
 279         up_write(&dev->me_clients_rwsem);
 280 }
 281
 282 /**
 283  * mei_me_cl_rm_by_uuid_id - remove all me clients matching client id
 284  *
 285  * @dev: the device structure
 286  * @uuid: me client uuid
 287  * @id: me client id
 288  *
 289  * Locking: called under "dev->device_lock" lock
 290  */
 291 void mei_me_cl_rm_by_uuid_id(struct mei_device *dev, const uuid_le *uuid, u8 id)
 292 {
 293         struct mei_me_client *me_cl;
 294
 295         dev_dbg(dev->dev, "remove %pUl %d\n", uuid, id);
 296
 297         down_write(&dev->me_clients_rwsem);
 298         me_cl = __mei_me_cl_by_uuid_id(dev, uuid, id);
 299         __mei_me_cl_del(dev, me_cl);
 300         up_write(&dev->me_clients_rwsem);
 301 }
 302
 303 /**
 304  * mei_me_cl_rm_all - remove all me clients
 305  *
 306  * @dev: the device structure
 307  *
 308  * Locking: called under "dev->device_lock" lock
 309  */
 310 void mei_me_cl_rm_all(struct mei_device *dev)
 311 {
 312         struct mei_me_client *me_cl, *next;
 313
 314         down_write(&dev->me_clients_rwsem);
 315         list_for_each_entry_safe(me_cl, next, &dev->me_clients, list)
 316                 __mei_me_cl_del(dev, me_cl);
 317         up_write(&dev->me_clients_rwsem);
 318 }
 319
 320 /**
 321  * mei_cl_cmp_id - tells if the clients are the same
 322  *
 323  * @cl1: host client 1
 324  * @cl2: host client 2
 325  *
 326  * Return: true  - if the clients has same host and me ids
 327  *         false - otherwise
 328  */
 329 static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
 330                                 const struct mei_cl *cl2)
 331 {
 332         return cl1 && cl2 &&
 333                 (cl1->host_client_id == cl2->host_client_id) &&
 334                 (mei_cl_me_id(cl1) == mei_cl_me_id(cl2));
 335 }
 336
 337 /**
 338  * mei_io_cb_free - free mei_cb_private related memory
 339  *
 340  * @cb: mei callback struct
 341  */
 342 void mei_io_cb_free(struct mei_cl_cb *cb)
 343 {
 344         if (cb == NULL)
 345                 return;
 346
 347         list_del(&cb->list);
 348         kfree(cb->buf.data);
 349         kfree(cb);
 350 }
 351
 352 /**
 353  * mei_io_cb_init - allocate and initialize io callback
 354  *
 355  * @cl: mei client
 356  * @type: operation type
 357  * @fp: pointer to file structure
 358  *
 359  * Return: mei_cl_cb pointer or NULL;
 360  */
 361 static struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl,
 362                                         enum mei_cb_file_ops type,
 363                                         const struct file *fp)
 364 {
 365         struct mei_cl_cb *cb;
 366
 367         cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
 368         if (!cb)
 369                 return NULL;
 370
 371         INIT_LIST_HEAD(&cb->list);
 372         cb->fp = fp;
 373         cb->cl = cl;
 374         cb->buf_idx = 0;
 375         cb->fop_type = type;
 376         return cb;
 377 }
 378
 379 /**
 380  * __mei_io_list_flush - removes and frees cbs belonging to cl.
 381  *
 382  * @list:  an instance of our list structure
 383  * @cl:    host client, can be NULL for flushing the whole list
 384  * @free:  whether to free the cbs
 385  */
 386 static void __mei_io_list_flush(struct mei_cl_cb *list,
 387                                 struct mei_cl *cl, bool free)
 388 {
 389         struct mei_cl_cb *cb, *next;
 390
 391         /* enable removing everything if no cl is specified */
 392         list_for_each_entry_safe(cb, next, &list->list, list) {
 393                 if (!cl || mei_cl_cmp_id(cl, cb->cl)) {
 394                         list_del_init(&cb->list);
 395                         if (free)
 396                                 mei_io_cb_free(cb);
 397                 }
 398         }
 399 }
 400
 401 /**
 402  * mei_io_list_flush - removes list entry belonging to cl.
 403  *
 404  * @list:  An instance of our list structure
 405  * @cl: host client
 406  */
 407 void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl)
 408 {
 409         __mei_io_list_flush(list, cl, false);
 410 }
 411
 412 /**
 413  * mei_io_list_free - removes cb belonging to cl and free them
 414  *
 415  * @list:  An instance of our list structure
 416  * @cl: host client
 417  */
 418 static inline void mei_io_list_free(struct mei_cl_cb *list, struct mei_cl *cl)
 419 {
 420         __mei_io_list_flush(list, cl, true);
 421 }
 422
 423 /**
 424  * mei_cl_alloc_cb - a convenient wrapper for allocating read cb
 425  *
 426  * @cl: host client
 427  * @length: size of the buffer
 428  * @fop_type: operation type
 429  * @fp: associated file pointer (might be NULL)
 430  *
 431  * Return: cb on success and NULL on failure
 432  */
 433 struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
 434                                   enum mei_cb_file_ops fop_type,
 435                                   const struct file *fp)
 436 {
 437         struct mei_cl_cb *cb;
 438
 439         cb = mei_io_cb_init(cl, fop_type, fp);
 440         if (!cb)
 441                 return NULL;
 442
 443         if (length == 0)
 444                 return cb;
 445
 446         cb->buf.data = kmalloc(length, GFP_KERNEL);
 447         if (!cb->buf.data) {
 448                 mei_io_cb_free(cb);
 449                 return NULL;
 450         }
 451         cb->buf.size = length;
 452
 453         return cb;
 454 }
 455
 456 /**
 457  * mei_cl_enqueue_ctrl_wr_cb - a convenient wrapper for allocating
 458  *     and enqueuing of the control commands cb
 459  *
 460  * @cl: host client
 461  * @length: size of the buffer
 462  * @fop_type: operation type
 463  * @fp: associated file pointer (might be NULL)
 464  *
 465  * Return: cb on success and NULL on failure
 466  * Locking: called under "dev->device_lock" lock
 467  */
 468 struct mei_cl_cb *mei_cl_enqueue_ctrl_wr_cb(struct mei_cl *cl, size_t length,
 469                                             enum mei_cb_file_ops fop_type,
 470                                             const struct file *fp)
 471 {
 472         struct mei_cl_cb *cb;
 473
 474         /* for RX always allocate at least client's mtu */
 475         if (length)
 476                 length = max_t(size_t, length, mei_cl_mtu(cl));
 477
 478         cb = mei_cl_alloc_cb(cl, length, fop_type, fp);
 479         if (!cb)
 480                 return NULL;
 481
 482         list_add_tail(&cb->list, &cl->dev->ctrl_wr_list.list);
 483         return cb;
 484 }
 485
 486 /**
 487  * mei_cl_read_cb - find this cl's callback in the read list
 488  *     for a specific file
 489  *
 490  * @cl: host client
 491  * @fp: file pointer (matching cb file object), may be NULL
 492  *
 493  * Return: cb on success, NULL if cb is not found
 494  */
 495 struct mei_cl_cb *mei_cl_read_cb(const struct mei_cl *cl, const struct file *fp)
 496 {
 497         struct mei_cl_cb *cb;
 498
 499         list_for_each_entry(cb, &cl->rd_completed, list)
 500                 if (!fp || fp == cb->fp)
 501                         return cb;
 502
 503         return NULL;
 504 }
 505
 506 /**
 507  * mei_cl_read_cb_flush - free client's read pending and completed cbs
 508  *   for a specific file
 509  *
 510  * @cl: host client
 511  * @fp: file pointer (matching cb file object), may be NULL
 512  */
 513 void mei_cl_read_cb_flush(const struct mei_cl *cl, const struct file *fp)
 514 {
 515         struct mei_cl_cb *cb, *next;
 516
 517         list_for_each_entry_safe(cb, next, &cl->rd_completed, list)
 518                 if (!fp || fp == cb->fp)
 519                         mei_io_cb_free(cb);
 520
 521
 522         list_for_each_entry_safe(cb, next, &cl->rd_pending, list)
 523                 if (!fp || fp == cb->fp)
 524                         mei_io_cb_free(cb);
 525 }
 526
 527 /**
 528  * mei_cl_flush_queues - flushes queue lists belonging to cl.
 529  *
 530  * @cl: host client
 531  * @fp: file pointer (matching cb file object), may be NULL
 532  *
 533  * Return: 0 on success, -EINVAL if cl or cl->dev is NULL.
 534  */
 535 int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp)
 536 {
 537         struct mei_device *dev;
 538
 539         if (WARN_ON(!cl || !cl->dev))
 540                 return -EINVAL;
 541
 542         dev = cl->dev;
 543
 544         cl_dbg(dev, cl, "remove list entry belonging to cl\n");
 545         mei_io_list_free(&cl->dev->write_list, cl);
 546         mei_io_list_free(&cl->dev->write_waiting_list, cl);
 547         mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
 548         mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
 549         mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
 550
 551         mei_cl_read_cb_flush(cl, fp);
 552
 553         return 0;
 554 }
 555
 556
 557 /**
 558  * mei_cl_init - initializes cl.
 559  *
 560  * @cl: host client to be initialized
 561  * @dev: mei device
 562  */
 563 void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
 564 {
 565         memset(cl, 0, sizeof(struct mei_cl));
 566         init_waitqueue_head(&cl->wait);
 567         init_waitqueue_head(&cl->rx_wait);
 568         init_waitqueue_head(&cl->tx_wait);
 569         init_waitqueue_head(&cl->ev_wait);
 570         INIT_LIST_HEAD(&cl->rd_completed);
 571         INIT_LIST_HEAD(&cl->rd_pending);
 572         INIT_LIST_HEAD(&cl->link);
 573         cl->writing_state = MEI_IDLE;
 574         cl->state = MEI_FILE_UNINITIALIZED;
 575         cl->dev = dev;
 576 }
 577
 578 /**
 579  * mei_cl_allocate - allocates cl  structure and sets it up.
 580  *
 581  * @dev: mei device
 582  * Return:  The allocated file or NULL on failure
 583  */
 584 struct mei_cl *mei_cl_allocate(struct mei_device *dev)
 585 {
 586         struct mei_cl *cl;
 587
 588         cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
 589         if (!cl)
 590                 return NULL;
 591
 592         mei_cl_init(cl, dev);
 593
 594         return cl;
 595 }
 596
 597 /**
 598  * mei_cl_link - allocate host id in the host map
 599  *
 600  * @cl: host client
 601  *
 602  * Return: 0 on success
 603  *      -EINVAL on incorrect values
 604  *      -EMFILE if open count exceeded.
 605  */
 606 int mei_cl_link(struct mei_cl *cl)
 607 {
 608         struct mei_device *dev;
 609         long open_handle_count;
 610         int id;
 611
 612         if (WARN_ON(!cl || !cl->dev))
 613                 return -EINVAL;
 614
 615         dev = cl->dev;
 616
 617         id = find_first_zero_bit(dev->host_clients_map, MEI_CLIENTS_MAX);
 618         if (id >= MEI_CLIENTS_MAX) {
 619                 dev_err(dev->dev, "id exceeded %d", MEI_CLIENTS_MAX);
 620                 return -EMFILE;
 621         }
 622
 623         open_handle_count = dev->open_handle_count + dev->iamthif_open_count;
 624         if (open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
 625                 dev_err(dev->dev, "open_handle_count exceeded %d",
 626                         MEI_MAX_OPEN_HANDLE_COUNT);
 627                 return -EMFILE;
 628         }
 629
 630         dev->open_handle_count++;
 631
 632         cl->host_client_id = id;
 633         list_add_tail(&cl->link, &dev->file_list);
 634
 635         set_bit(id, dev->host_clients_map);
 636
 637         cl->state = MEI_FILE_INITIALIZING;
 638
 639         cl_dbg(dev, cl, "link cl\n");
 640         return 0;
 641 }
 642
 643 /**
 644  * mei_cl_unlink - remove host client from the list
 645  *
 646  * @cl: host client
 647  *
 648  * Return: always 0
 649  */
 650 int mei_cl_unlink(struct mei_cl *cl)
 651 {
 652         struct mei_device *dev;
 653
 654         /* don't shout on error exit path */
 655         if (!cl)
 656                 return 0;
 657
 658         /* amthif might not be initialized */
 659         if (!cl->dev)
 660                 return 0;
 661
 662         dev = cl->dev;
 663
 664         cl_dbg(dev, cl, "unlink client");
 665
 666         if (dev->open_handle_count > 0)
 667                 dev->open_handle_count--;
 668
 669         /* never clear the 0 bit */
 670         if (cl->host_client_id)
 671                 clear_bit(cl->host_client_id, dev->host_clients_map);
 672
 673         list_del_init(&cl->link);
 674
 675         cl->state = MEI_FILE_UNINITIALIZED;
 676         cl->writing_state = MEI_IDLE;
 677
 678         WARN_ON(!list_empty(&cl->rd_completed) ||
 679                 !list_empty(&cl->rd_pending) ||
 680                 !list_empty(&cl->link));
 681
 682         return 0;
 683 }
 684
 685 void mei_host_client_init(struct mei_device *dev)
 686 {
 687         dev->dev_state = MEI_DEV_ENABLED;
 688         dev->reset_count = 0;
 689
 690         schedule_work(&dev->bus_rescan_work);
 691
 692         pm_runtime_mark_last_busy(dev->dev);
 693         dev_dbg(dev->dev, "rpm: autosuspend\n");
 694         pm_request_autosuspend(dev->dev);
 695 }
 696
 697 /**
 698  * mei_hbuf_acquire - try to acquire host buffer
 699  *
 700  * @dev: the device structure
 701  * Return: true if host buffer was acquired
 702  */
 703 bool mei_hbuf_acquire(struct mei_device *dev)
 704 {
 705         if (mei_pg_state(dev) == MEI_PG_ON ||
 706             mei_pg_in_transition(dev)) {
 707                 dev_dbg(dev->dev, "device is in pg\n");
 708                 return false;
 709         }
 710
 711         if (!dev->hbuf_is_ready) {
 712                 dev_dbg(dev->dev, "hbuf is not ready\n");
 713                 return false;
 714         }
 715
 716         dev->hbuf_is_ready = false;
 717
 718         return true;
 719 }
 720
 721 /**
 722  * mei_cl_wake_all - wake up readers, writers and event waiters so
 723  *                 they can be interrupted
 724  *
 725  * @cl: host client
 726  */
 727 static void mei_cl_wake_all(struct mei_cl *cl)
 728 {
 729         struct mei_device *dev = cl->dev;
 730
 731         /* synchronized under device mutex */
 732         if (waitqueue_active(&cl->rx_wait)) {
 733                 cl_dbg(dev, cl, "Waking up reading client!\n");
 734                 wake_up_interruptible(&cl->rx_wait);
 735         }
 736         /* synchronized under device mutex */
 737         if (waitqueue_active(&cl->tx_wait)) {
 738                 cl_dbg(dev, cl, "Waking up writing client!\n");
 739                 wake_up_interruptible(&cl->tx_wait);
 740         }
 741         /* synchronized under device mutex */
 742         if (waitqueue_active(&cl->ev_wait)) {
 743                 cl_dbg(dev, cl, "Waking up waiting for event clients!\n");
 744                 wake_up_interruptible(&cl->ev_wait);
 745         }
 746         /* synchronized under device mutex */
 747         if (waitqueue_active(&cl->wait)) {
 748                 cl_dbg(dev, cl, "Waking up ctrl write clients!\n");
 749                 wake_up(&cl->wait);
 750         }
 751 }
 752
 753 /**
 754  * mei_cl_set_disconnected - set disconnected state and clear
 755  *   associated states and resources
 756  *
 757  * @cl: host client
 758  */
 759 void mei_cl_set_disconnected(struct mei_cl *cl)
 760 {
 761         struct mei_device *dev = cl->dev;
 762
 763         if (cl->state == MEI_FILE_DISCONNECTED ||
 764             cl->state <= MEI_FILE_INITIALIZING)
 765                 return;
 766
 767         cl->state = MEI_FILE_DISCONNECTED;
 768         mei_io_list_free(&dev->write_list, cl);
 769         mei_io_list_free(&dev->write_waiting_list, cl);
 770         mei_io_list_flush(&dev->ctrl_rd_list, cl);
 771         mei_io_list_flush(&dev->ctrl_wr_list, cl);
 772         mei_cl_wake_all(cl);
 773         cl->rx_flow_ctrl_creds = 0;
 774         cl->tx_flow_ctrl_creds = 0;
 775         cl->timer_count = 0;
 776
 777         if (!cl->me_cl)
 778                 return;
 779
 780         if (!WARN_ON(cl->me_cl->connect_count == 0))
 781                 cl->me_cl->connect_count--;
 782
 783         if (cl->me_cl->connect_count == 0)
 784                 cl->me_cl->tx_flow_ctrl_creds = 0;
 785
 786         mei_me_cl_put(cl->me_cl);
 787         cl->me_cl = NULL;
 788 }
 789
 790 static int mei_cl_set_connecting(struct mei_cl *cl, struct mei_me_client *me_cl)
 791 {
 792         if (!mei_me_cl_get(me_cl))
 793                 return -ENOENT;
 794
 795         /* only one connection is allowed for fixed address clients */
 796         if (me_cl->props.fixed_address) {
 797                 if (me_cl->connect_count) {
 798                         mei_me_cl_put(me_cl);
 799                         return -EBUSY;
 800                 }
 801         }
 802
 803         cl->me_cl = me_cl;
 804         cl->state = MEI_FILE_CONNECTING;
 805         cl->me_cl->connect_count++;
 806
 807         return 0;
 808 }
 809
 810 /*
 811  * mei_cl_send_disconnect - send disconnect request
 812  *
 813  * @cl: host client
 814  * @cb: callback block
 815  *
 816  * Return: 0, OK; otherwise, error.
 817  */
 818 static int mei_cl_send_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb)
 819 {
 820         struct mei_device *dev;
 821         int ret;
 822
 823         dev = cl->dev;
 824
 825         ret = mei_hbm_cl_disconnect_req(dev, cl);
 826         cl->status = ret;
 827         if (ret) {
 828                 cl->state = MEI_FILE_DISCONNECT_REPLY;
 829                 return ret;
 830         }
 831
 832         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 833         cl->timer_count = MEI_CONNECT_TIMEOUT;
 834         mei_schedule_stall_timer(dev);
 835
 836         return 0;
 837 }
 838
 839 /**
 840  * mei_cl_irq_disconnect - processes close related operation from
 841  *      interrupt thread context - send disconnect request
 842  *
 843  * @cl: client
 844  * @cb: callback block.
 845  * @cmpl_list: complete list.
 846  *
 847  * Return: 0, OK; otherwise, error.
 848  */
 849 int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
 850                             struct mei_cl_cb *cmpl_list)
 851 {
 852         struct mei_device *dev = cl->dev;
 853         u32 msg_slots;
 854         int slots;
 855         int ret;
 856
 857         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 858         slots = mei_hbuf_empty_slots(dev);
 859
 860         if (slots < msg_slots)
 861                 return -EMSGSIZE;
 862
 863         ret = mei_cl_send_disconnect(cl, cb);
 864         if (ret)
 865                 list_move_tail(&cb->list, &cmpl_list->list);
 866
 867         return ret;
 868 }
 869
 870 /**
 871  * __mei_cl_disconnect - disconnect host client from the me one
 872  *     internal function runtime pm has to be already acquired
 873  *
 874  * @cl: host client
 875  *
 876  * Return: 0 on success, <0 on failure.
 877  */
 878 static int __mei_cl_disconnect(struct mei_cl *cl)
 879 {
 880         struct mei_device *dev;
 881         struct mei_cl_cb *cb;
 882         int rets;
 883
 884         dev = cl->dev;
 885
 886         cl->state = MEI_FILE_DISCONNECTING;
 887
 888         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT, NULL);
 889         if (!cb) {
 890                 rets = -ENOMEM;
 891                 goto out;
 892         }
 893
 894         if (mei_hbuf_acquire(dev)) {
 895                 rets = mei_cl_send_disconnect(cl, cb);
 896                 if (rets) {
 897                         cl_err(dev, cl, "failed to disconnect.\n");
 898                         goto out;
 899                 }
 900         }
 901
 902         mutex_unlock(&dev->device_lock);
 903         wait_event_timeout(cl->wait,
 904                            cl->state == MEI_FILE_DISCONNECT_REPLY ||
 905                            cl->state == MEI_FILE_DISCONNECTED,
 906                            mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 907         mutex_lock(&dev->device_lock);
 908
 909         rets = cl->status;
 910         if (cl->state != MEI_FILE_DISCONNECT_REPLY &&
 911             cl->state != MEI_FILE_DISCONNECTED) {
 912                 cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
 913                 rets = -ETIME;
 914         }
 915
 916 out:
 917         /* we disconnect also on error */
 918         mei_cl_set_disconnected(cl);
 919         if (!rets)
 920                 cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
 921
 922         mei_io_cb_free(cb);
 923         return rets;
 924 }
 925
 926 /**
 927  * mei_cl_disconnect - disconnect host client from the me one
 928  *
 929  * @cl: host client
 930  *
 931  * Locking: called under "dev->device_lock" lock
 932  *
 933  * Return: 0 on success, <0 on failure.
 934  */
 935 int mei_cl_disconnect(struct mei_cl *cl)
 936 {
 937         struct mei_device *dev;
 938         int rets;
 939
 940         if (WARN_ON(!cl || !cl->dev))
 941                 return -ENODEV;
 942
 943         dev = cl->dev;
 944
 945         cl_dbg(dev, cl, "disconnecting");
 946
 947         if (!mei_cl_is_connected(cl))
 948                 return 0;
 949
 950         if (mei_cl_is_fixed_address(cl)) {
 951                 mei_cl_set_disconnected(cl);
 952                 return 0;
 953         }
 954
 955         rets = pm_runtime_get(dev->dev);
 956         if (rets < 0 && rets != -EINPROGRESS) {
 957                 pm_runtime_put_noidle(dev->dev);
 958                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
 959                 return rets;
 960         }
 961
 962         rets = __mei_cl_disconnect(cl);
 963
 964         cl_dbg(dev, cl, "rpm: autosuspend\n");
 965         pm_runtime_mark_last_busy(dev->dev);
 966         pm_runtime_put_autosuspend(dev->dev);
 967
 968         return rets;
 969 }
 970
 971
 972 /**
 973  * mei_cl_is_other_connecting - checks if other
 974  *    client with the same me client id is connecting
 975  *
 976  * @cl: private data of the file object
 977  *
 978  * Return: true if other client is connected, false - otherwise.
 979  */
 980 static bool mei_cl_is_other_connecting(struct mei_cl *cl)
 981 {
 982         struct mei_device *dev;
 983         struct mei_cl_cb *cb;
 984
 985         dev = cl->dev;
 986
 987         list_for_each_entry(cb, &dev->ctrl_rd_list.list, list) {
 988                 if (cb->fop_type == MEI_FOP_CONNECT &&
 989                     mei_cl_me_id(cl) == mei_cl_me_id(cb->cl))
 990                         return true;
 991         }
 992
 993         return false;
 994 }
 995
 996 /**
 997  * mei_cl_send_connect - send connect request
 998  *
 999  * @cl: host client
1000  * @cb: callback block
1001  *
1002  * Return: 0, OK; otherwise, error.
1003  */
1004 static int mei_cl_send_connect(struct mei_cl *cl, struct mei_cl_cb *cb)
1005 {
1006         struct mei_device *dev;
1007         int ret;
1008
1009         dev = cl->dev;
1010
1011         ret = mei_hbm_cl_connect_req(dev, cl);
1012         cl->status = ret;
1013         if (ret) {
1014                 cl->state = MEI_FILE_DISCONNECT_REPLY;
1015                 return ret;
1016         }
1017
1018         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
1019         cl->timer_count = MEI_CONNECT_TIMEOUT;
1020         mei_schedule_stall_timer(dev);
1021         return 0;
1022 }
1023
1024 /**
1025  * mei_cl_irq_connect - send connect request in irq_thread context
1026  *
1027  * @cl: host client
1028  * @cb: callback block
1029  * @cmpl_list: complete list
1030  *
1031  * Return: 0, OK; otherwise, error.
1032  */
1033 int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
1034                               struct mei_cl_cb *cmpl_list)
1035 {
1036         struct mei_device *dev = cl->dev;
1037         u32 msg_slots;
1038         int slots;
1039         int rets;
1040
1041         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1042         slots = mei_hbuf_empty_slots(dev);
1043
1044         if (mei_cl_is_other_connecting(cl))
1045                 return 0;
1046
1047         if (slots < msg_slots)
1048                 return -EMSGSIZE;
1049
1050         rets = mei_cl_send_connect(cl, cb);
1051         if (rets)
1052                 list_move_tail(&cb->list, &cmpl_list->list);
1053
1054         return rets;
1055 }
1056
1057 /**
1058  * mei_cl_connect - connect host client to the me one
1059  *
1060  * @cl: host client
1061  * @me_cl: me client
1062  * @fp: pointer to file structure
1063  *
1064  * Locking: called under "dev->device_lock" lock
1065  *
1066  * Return: 0 on success, <0 on failure.
1067  */
1068 int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
1069                    const struct file *fp)
1070 {
1071         struct mei_device *dev;
1072         struct mei_cl_cb *cb;
1073         int rets;
1074
1075         if (WARN_ON(!cl || !cl->dev || !me_cl))
1076                 return -ENODEV;
1077
1078         dev = cl->dev;
1079
1080         rets = mei_cl_set_connecting(cl, me_cl);
1081         if (rets)
1082                 return rets;
1083
1084         if (mei_cl_is_fixed_address(cl)) {
1085                 cl->state = MEI_FILE_CONNECTED;
1086                 return 0;
1087         }
1088
1089         rets = pm_runtime_get(dev->dev);
1090         if (rets < 0 && rets != -EINPROGRESS) {
1091                 pm_runtime_put_noidle(dev->dev);
1092                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1093                 goto nortpm;
1094         }
1095
1096         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_CONNECT, fp);
1097         if (!cb) {
1098                 rets = -ENOMEM;
1099                 goto out;
1100         }
1101
1102         /* run hbuf acquire last so we don't have to undo */
1103         if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
1104                 rets = mei_cl_send_connect(cl, cb);
1105                 if (rets)
1106                         goto out;
1107         }
1108
1109         mutex_unlock(&dev->device_lock);
1110         wait_event_timeout(cl->wait,
1111                         (cl->state == MEI_FILE_CONNECTED ||
1112                          cl->state == MEI_FILE_DISCONNECTED ||
1113                          cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
1114                          cl->state == MEI_FILE_DISCONNECT_REPLY),
1115                         mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1116         mutex_lock(&dev->device_lock);
1117
1118         if (!mei_cl_is_connected(cl)) {
1119                 if (cl->state == MEI_FILE_DISCONNECT_REQUIRED) {
1120                         mei_io_list_flush(&dev->ctrl_rd_list, cl);
1121                         mei_io_list_flush(&dev->ctrl_wr_list, cl);
1122                          /* ignore disconnect return valuue;
1123                           * in case of failure reset will be invoked
1124                           */
1125                         __mei_cl_disconnect(cl);
1126                         rets = -EFAULT;
1127                         goto out;
1128                 }
1129
1130                 /* timeout or something went really wrong */
1131                 if (!cl->status)
1132                         cl->status = -EFAULT;
1133         }
1134
1135         rets = cl->status;
1136 out:
1137         cl_dbg(dev, cl, "rpm: autosuspend\n");
1138         pm_runtime_mark_last_busy(dev->dev);
1139         pm_runtime_put_autosuspend(dev->dev);
1140
1141         mei_io_cb_free(cb);
1142
1143 nortpm:
1144         if (!mei_cl_is_connected(cl))
1145                 mei_cl_set_disconnected(cl);
1146
1147         return rets;
1148 }
1149
1150 /**
1151  * mei_cl_alloc_linked - allocate and link host client
1152  *
1153  * @dev: the device structure
1154  *
1155  * Return: cl on success ERR_PTR on failure
1156  */
1157 struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev)
1158 {
1159         struct mei_cl *cl;
1160         int ret;
1161
1162         cl = mei_cl_allocate(dev);
1163         if (!cl) {
1164                 ret = -ENOMEM;
1165                 goto err;
1166         }
1167
1168         ret = mei_cl_link(cl);
1169         if (ret)
1170                 goto err;
1171
1172         return cl;
1173 err:
1174         kfree(cl);
1175         return ERR_PTR(ret);
1176 }
1177
1178 /**
1179  * mei_cl_tx_flow_ctrl_creds - checks flow_control credits for cl.
1180  *
1181  * @cl: host client
1182  *
1183  * Return: 1 if tx_flow_ctrl_creds >0, 0 - otherwise.
1184  */
1185 static int mei_cl_tx_flow_ctrl_creds(struct mei_cl *cl)
1186 {
1187         if (WARN_ON(!cl || !cl->me_cl))
1188                 return -EINVAL;
1189
1190         if (cl->tx_flow_ctrl_creds > 0)
1191                 return 1;
1192
1193         if (mei_cl_is_fixed_address(cl))
1194                 return 1;
1195
1196         if (mei_cl_is_single_recv_buf(cl)) {
1197                 if (cl->me_cl->tx_flow_ctrl_creds > 0)
1198                         return 1;
1199         }
1200         return 0;
1201 }
1202
1203 /**
1204  * mei_cl_tx_flow_ctrl_creds_reduce - reduces transmit flow control credits
1205  *   for a client
1206  *
1207  * @cl: host client
1208  *
1209  * Return:
1210  *      0 on success
1211  *      -EINVAL when ctrl credits are <= 0
1212  */
1213 static int mei_cl_tx_flow_ctrl_creds_reduce(struct mei_cl *cl)
1214 {
1215         if (WARN_ON(!cl || !cl->me_cl))
1216                 return -EINVAL;
1217
1218         if (mei_cl_is_fixed_address(cl))
1219                 return 0;
1220
1221         if (mei_cl_is_single_recv_buf(cl)) {
1222                 if (WARN_ON(cl->me_cl->tx_flow_ctrl_creds <= 0))
1223                         return -EINVAL;
1224                 cl->me_cl->tx_flow_ctrl_creds--;
1225         } else {
1226                 if (WARN_ON(cl->tx_flow_ctrl_creds <= 0))
1227                         return -EINVAL;
1228                 cl->tx_flow_ctrl_creds--;
1229         }
1230         return 0;
1231 }
1232
1233 /**
1234  *  mei_cl_notify_fop2req - convert fop to proper request
1235  *
1236  * @fop: client notification start response command
1237  *
1238  * Return:  MEI_HBM_NOTIFICATION_START/STOP
1239  */
1240 u8 mei_cl_notify_fop2req(enum mei_cb_file_ops fop)
1241 {
1242         if (fop == MEI_FOP_NOTIFY_START)
1243                 return MEI_HBM_NOTIFICATION_START;
1244         else
1245                 return MEI_HBM_NOTIFICATION_STOP;
1246 }
1247
1248 /**
1249  *  mei_cl_notify_req2fop - convert notification request top file operation type
1250  *
1251  * @req: hbm notification request type
1252  *
1253  * Return:  MEI_FOP_NOTIFY_START/STOP
1254  */
1255 enum mei_cb_file_ops mei_cl_notify_req2fop(u8 req)
1256 {
1257         if (req == MEI_HBM_NOTIFICATION_START)
1258                 return MEI_FOP_NOTIFY_START;
1259         else
1260                 return MEI_FOP_NOTIFY_STOP;
1261 }
1262
1263 /**
1264  * mei_cl_irq_notify - send notification request in irq_thread context
1265  *
1266  * @cl: client
1267  * @cb: callback block.
1268  * @cmpl_list: complete list.
1269  *
1270  * Return: 0 on such and error otherwise.
1271  */
1272 int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
1273                       struct mei_cl_cb *cmpl_list)
1274 {
1275         struct mei_device *dev = cl->dev;
1276         u32 msg_slots;
1277         int slots;
1278         int ret;
1279         bool request;
1280
1281         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1282         slots = mei_hbuf_empty_slots(dev);
1283
1284         if (slots < msg_slots)
1285                 return -EMSGSIZE;
1286
1287         request = mei_cl_notify_fop2req(cb->fop_type);
1288         ret = mei_hbm_cl_notify_req(dev, cl, request);
1289         if (ret) {
1290                 cl->status = ret;
1291                 list_move_tail(&cb->list, &cmpl_list->list);
1292                 return ret;
1293         }
1294
1295         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
1296         return 0;
1297 }
1298
1299 /**
1300  * mei_cl_notify_request - send notification stop/start request
1301  *
1302  * @cl: host client
1303  * @fp: associate request with file
1304  * @request: 1 for start or 0 for stop
1305  *
1306  * Locking: called under "dev->device_lock" lock
1307  *
1308  * Return: 0 on such and error otherwise.
1309  */
1310 int mei_cl_notify_request(struct mei_cl *cl,
1311                           const struct file *fp, u8 request)
1312 {
1313         struct mei_device *dev;
1314         struct mei_cl_cb *cb;
1315         enum mei_cb_file_ops fop_type;
1316         int rets;
1317
1318         if (WARN_ON(!cl || !cl->dev))
1319                 return -ENODEV;
1320
1321         dev = cl->dev;
1322
1323         if (!dev->hbm_f_ev_supported) {
1324                 cl_dbg(dev, cl, "notifications not supported\n");
1325                 return -EOPNOTSUPP;
1326         }
1327
1328         rets = pm_runtime_get(dev->dev);
1329         if (rets < 0 && rets != -EINPROGRESS) {
1330                 pm_runtime_put_noidle(dev->dev);
1331                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1332                 return rets;
1333         }
1334
1335         fop_type = mei_cl_notify_req2fop(request);
1336         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, fop_type, fp);
1337         if (!cb) {
1338                 rets = -ENOMEM;
1339                 goto out;
1340         }
1341
1342         if (mei_hbuf_acquire(dev)) {
1343                 if (mei_hbm_cl_notify_req(dev, cl, request)) {
1344                         rets = -ENODEV;
1345                         goto out;
1346                 }
1347                 list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
1348         }
1349
1350         mutex_unlock(&dev->device_lock);
1351         wait_event_timeout(cl->wait,
1352                            cl->notify_en == request || !mei_cl_is_connected(cl),
1353                            mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1354         mutex_lock(&dev->device_lock);
1355
1356         if (cl->notify_en != request && !cl->status)
1357                 cl->status = -EFAULT;
1358
1359         rets = cl->status;
1360
1361 out:
1362         cl_dbg(dev, cl, "rpm: autosuspend\n");
1363         pm_runtime_mark_last_busy(dev->dev);
1364         pm_runtime_put_autosuspend(dev->dev);
1365
1366         mei_io_cb_free(cb);
1367         return rets;
1368 }
1369
1370 /**
1371  * mei_cl_notify - raise notification
1372  *
1373  * @cl: host client
1374  *
1375  * Locking: called under "dev->device_lock" lock
1376  */
1377 void mei_cl_notify(struct mei_cl *cl)
1378 {
1379         struct mei_device *dev;
1380
1381         if (!cl || !cl->dev)
1382                 return;
1383
1384         dev = cl->dev;
1385
1386         if (!cl->notify_en)
1387                 return;
1388
1389         cl_dbg(dev, cl, "notify event");
1390         cl->notify_ev = true;
1391         if (!mei_cl_bus_notify_event(cl))
1392                 wake_up_interruptible(&cl->ev_wait);
1393
1394         if (cl->ev_async)
1395                 kill_fasync(&cl->ev_async, SIGIO, POLL_PRI);
1396
1397 }
1398
1399 /**
1400  * mei_cl_notify_get - get or wait for notification event
1401  *
1402  * @cl: host client
1403  * @block: this request is blocking
1404  * @notify_ev: true if notification event was received
1405  *
1406  * Locking: called under "dev->device_lock" lock
1407  *
1408  * Return: 0 on such and error otherwise.
1409  */
1410 int mei_cl_notify_get(struct mei_cl *cl, bool block, bool *notify_ev)
1411 {
1412         struct mei_device *dev;
1413         int rets;
1414
1415         *notify_ev = false;
1416
1417         if (WARN_ON(!cl || !cl->dev))
1418                 return -ENODEV;
1419
1420         dev = cl->dev;
1421
1422         if (!mei_cl_is_connected(cl))
1423                 return -ENODEV;
1424
1425         if (cl->notify_ev)
1426                 goto out;
1427
1428         if (!block)
1429                 return -EAGAIN;
1430
1431         mutex_unlock(&dev->device_lock);
1432         rets = wait_event_interruptible(cl->ev_wait, cl->notify_ev);
1433         mutex_lock(&dev->device_lock);
1434
1435         if (rets < 0)
1436                 return rets;
1437
1438 out:
1439         *notify_ev = cl->notify_ev;
1440         cl->notify_ev = false;
1441         return 0;
1442 }
1443
1444 /**
1445  * mei_cl_read_start - the start read client message function.
1446  *
1447  * @cl: host client
1448  * @length: number of bytes to read
1449  * @fp: pointer to file structure
1450  *
1451  * Return: 0 on success, <0 on failure.
1452  */
1453 int mei_cl_read_start(struct mei_cl *cl, size_t length, const struct file *fp)
1454 {
1455         struct mei_device *dev;
1456         struct mei_cl_cb *cb;
1457         int rets;
1458
1459         if (WARN_ON(!cl || !cl->dev))
1460                 return -ENODEV;
1461
1462         dev = cl->dev;
1463
1464         if (!mei_cl_is_connected(cl))
1465                 return -ENODEV;
1466
1467         if (!mei_me_cl_is_active(cl->me_cl)) {
1468                 cl_err(dev, cl, "no such me client\n");
1469                 return  -ENOTTY;
1470         }
1471
1472         if (mei_cl_is_fixed_address(cl) || cl == &dev->iamthif_cl)
1473                 return 0;
1474
1475         /* HW currently supports only one pending read */
1476         if (cl->rx_flow_ctrl_creds)
1477                 return -EBUSY;
1478
1479         cb = mei_cl_enqueue_ctrl_wr_cb(cl, length, MEI_FOP_READ, fp);
1480         if (!cb)
1481                 return -ENOMEM;
1482
1483         rets = pm_runtime_get(dev->dev);
1484         if (rets < 0 && rets != -EINPROGRESS) {
1485                 pm_runtime_put_noidle(dev->dev);
1486                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1487                 goto nortpm;
1488         }
1489
1490         rets = 0;
1491         if (mei_hbuf_acquire(dev)) {
1492                 rets = mei_hbm_cl_flow_control_req(dev, cl);
1493                 if (rets < 0)
1494                         goto out;
1495
1496                 list_move_tail(&cb->list, &cl->rd_pending);
1497         }
1498         cl->rx_flow_ctrl_creds++;
1499
1500 out:
1501         cl_dbg(dev, cl, "rpm: autosuspend\n");
1502         pm_runtime_mark_last_busy(dev->dev);
1503         pm_runtime_put_autosuspend(dev->dev);
1504 nortpm:
1505         if (rets)
1506                 mei_io_cb_free(cb);
1507
1508         return rets;
1509 }
1510
1511 /**
1512  * mei_cl_irq_write - write a message to device
1513  *      from the interrupt thread context
1514  *
1515  * @cl: client
1516  * @cb: callback block.
1517  * @cmpl_list: complete list.
1518  *
1519  * Return: 0, OK; otherwise error.
1520  */
1521 int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
1522                      struct mei_cl_cb *cmpl_list)
1523 {
1524         struct mei_device *dev;
1525         struct mei_msg_data *buf;
1526         struct mei_msg_hdr mei_hdr;
1527         size_t len;
1528         u32 msg_slots;
1529         int slots;
1530         int rets;
1531         bool first_chunk;
1532
1533         if (WARN_ON(!cl || !cl->dev))
1534                 return -ENODEV;
1535
1536         dev = cl->dev;
1537
1538         buf = &cb->buf;
1539
1540         first_chunk = cb->buf_idx == 0;
1541
1542         rets = first_chunk ? mei_cl_tx_flow_ctrl_creds(cl) : 1;
1543         if (rets < 0)
1544                 return rets;
1545
1546         if (rets == 0) {
1547                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1548                 return 0;
1549         }
1550
1551         slots = mei_hbuf_empty_slots(dev);
1552         len = buf->size - cb->buf_idx;
1553         msg_slots = mei_data2slots(len);
1554
1555         mei_hdr.host_addr = mei_cl_host_addr(cl);
1556         mei_hdr.me_addr = mei_cl_me_id(cl);
1557         mei_hdr.reserved = 0;
1558         mei_hdr.internal = cb->internal;
1559
1560         if (slots >= msg_slots) {
1561                 mei_hdr.length = len;
1562                 mei_hdr.msg_complete = 1;
1563         /* Split the message only if we can write the whole host buffer */
1564         } else if (slots == dev->hbuf_depth) {
1565                 msg_slots = slots;
1566                 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
1567                 mei_hdr.length = len;
1568                 mei_hdr.msg_complete = 0;
1569         } else {
1570                 /* wait for next time the host buffer is empty */
1571                 return 0;
1572         }
1573
1574         cl_dbg(dev, cl, "buf: size = %zu idx = %zu\n",
1575                         cb->buf.size, cb->buf_idx);
1576
1577         rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
1578         if (rets) {
1579                 cl->status = rets;
1580                 list_move_tail(&cb->list, &cmpl_list->list);
1581                 return rets;
1582         }
1583
1584         cl->status = 0;
1585         cl->writing_state = MEI_WRITING;
1586         cb->buf_idx += mei_hdr.length;
1587         cb->completed = mei_hdr.msg_complete == 1;
1588
1589         if (first_chunk) {
1590                 if (mei_cl_tx_flow_ctrl_creds_reduce(cl))
1591                         return -EIO;
1592         }
1593
1594         if (mei_hdr.msg_complete)
1595                 list_move_tail(&cb->list, &dev->write_waiting_list.list);
1596
1597         return 0;
1598 }
1599
1600 /**
1601  * mei_cl_write - submit a write cb to mei device
1602  *      assumes device_lock is locked
1603  *
1604  * @cl: host client
1605  * @cb: write callback with filled data
1606  *
1607  * Return: number of bytes sent on success, <0 on failure.
1608  */
1609 int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb)
1610 {
1611         struct mei_device *dev;
1612         struct mei_msg_data *buf;
1613         struct mei_msg_hdr mei_hdr;
1614         int size;
1615         int rets;
1616         bool blocking;
1617
1618         if (WARN_ON(!cl || !cl->dev))
1619                 return -ENODEV;
1620
1621         if (WARN_ON(!cb))
1622                 return -EINVAL;
1623
1624         dev = cl->dev;
1625
1626         buf = &cb->buf;
1627         size = buf->size;
1628         blocking = cb->blocking;
1629
1630         cl_dbg(dev, cl, "size=%d\n", size);
1631
1632         rets = pm_runtime_get(dev->dev);
1633         if (rets < 0 && rets != -EINPROGRESS) {
1634                 pm_runtime_put_noidle(dev->dev);
1635                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1636                 goto free;
1637         }
1638
1639         cb->buf_idx = 0;
1640         cl->writing_state = MEI_IDLE;
1641
1642         mei_hdr.host_addr = mei_cl_host_addr(cl);
1643         mei_hdr.me_addr = mei_cl_me_id(cl);
1644         mei_hdr.reserved = 0;
1645         mei_hdr.msg_complete = 0;
1646         mei_hdr.internal = cb->internal;
1647
1648         rets = mei_cl_tx_flow_ctrl_creds(cl);
1649         if (rets < 0)
1650                 goto err;
1651
1652         if (rets == 0) {
1653                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1654                 rets = size;
1655                 goto out;
1656         }
1657         if (!mei_hbuf_acquire(dev)) {
1658                 cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
1659                 rets = size;
1660                 goto out;
1661         }
1662
1663         /* Check for a maximum length */
1664         if (size > mei_hbuf_max_len(dev)) {
1665                 mei_hdr.length = mei_hbuf_max_len(dev);
1666                 mei_hdr.msg_complete = 0;
1667         } else {
1668                 mei_hdr.length = size;
1669                 mei_hdr.msg_complete = 1;
1670         }
1671
1672         rets = mei_write_message(dev, &mei_hdr, buf->data);
1673         if (rets)
1674                 goto err;
1675
1676         rets = mei_cl_tx_flow_ctrl_creds_reduce(cl);
1677         if (rets)
1678                 goto err;
1679
1680         cl->writing_state = MEI_WRITING;
1681         cb->buf_idx = mei_hdr.length;
1682         cb->completed = mei_hdr.msg_complete == 1;
1683
1684 out:
1685         if (mei_hdr.msg_complete)
1686                 list_add_tail(&cb->list, &dev->write_waiting_list.list);
1687         else
1688                 list_add_tail(&cb->list, &dev->write_list.list);
1689
1690         cb = NULL;
1691         if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
1692
1693                 mutex_unlock(&dev->device_lock);
1694                 rets = wait_event_interruptible(cl->tx_wait,
1695                                 cl->writing_state == MEI_WRITE_COMPLETE ||
1696                                 (!mei_cl_is_connected(cl)));
1697                 mutex_lock(&dev->device_lock);
1698                 /* wait_event_interruptible returns -ERESTARTSYS */
1699                 if (rets) {
1700                         if (signal_pending(current))
1701                                 rets = -EINTR;
1702                         goto err;
1703                 }
1704                 if (cl->writing_state != MEI_WRITE_COMPLETE) {
1705                         rets = -EFAULT;
1706                         goto err;
1707                 }
1708         }
1709
1710         rets = size;
1711 err:
1712         cl_dbg(dev, cl, "rpm: autosuspend\n");
1713         pm_runtime_mark_last_busy(dev->dev);
1714         pm_runtime_put_autosuspend(dev->dev);
1715 free:
1716         mei_io_cb_free(cb);
1717
1718         return rets;
1719 }
1720
1721
1722 /**
1723  * mei_cl_complete - processes completed operation for a client
1724  *
1725  * @cl: private data of the file object.
1726  * @cb: callback block.
1727  */
1728 void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
1729 {
1730         struct mei_device *dev = cl->dev;
1731
1732         switch (cb->fop_type) {
1733         case MEI_FOP_WRITE:
1734                 mei_io_cb_free(cb);
1735                 cl->writing_state = MEI_WRITE_COMPLETE;
1736                 if (waitqueue_active(&cl->tx_wait)) {
1737                         wake_up_interruptible(&cl->tx_wait);
1738                 } else {
1739                         pm_runtime_mark_last_busy(dev->dev);
1740                         pm_request_autosuspend(dev->dev);
1741                 }
1742                 break;
1743
1744         case MEI_FOP_READ:
1745                 list_add_tail(&cb->list, &cl->rd_completed);
1746                 if (!mei_cl_is_fixed_address(cl) &&
1747                     !WARN_ON(!cl->rx_flow_ctrl_creds))
1748                         cl->rx_flow_ctrl_creds--;
1749                 if (!mei_cl_bus_rx_event(cl))
1750                         wake_up_interruptible(&cl->rx_wait);
1751                 break;
1752
1753         case MEI_FOP_CONNECT:
1754         case MEI_FOP_DISCONNECT:
1755         case MEI_FOP_NOTIFY_STOP:
1756         case MEI_FOP_NOTIFY_START:
1757                 if (waitqueue_active(&cl->wait))
1758                         wake_up(&cl->wait);
1759
1760                 break;
1761         case MEI_FOP_DISCONNECT_RSP:
1762                 mei_io_cb_free(cb);
1763                 mei_cl_set_disconnected(cl);
1764                 break;
1765         default:
1766                 BUG_ON(0);
1767         }
1768 }
1769
1770
1771 /**
1772  * mei_cl_all_disconnect - disconnect forcefully all connected clients
1773  *
1774  * @dev: mei device
1775  */
1776 void mei_cl_all_disconnect(struct mei_device *dev)
1777 {
1778         struct mei_cl *cl;
1779
1780         list_for_each_entry(cl, &dev->file_list, link)
1781                 mei_cl_set_disconnected(cl);
1782 }