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 struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, enum mei_cb_file_ops type,
 362                                  const struct file *fp)
 363 {
 364         struct mei_cl_cb *cb;
 365
 366         cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
 367         if (!cb)
 368                 return NULL;
 369
 370         INIT_LIST_HEAD(&cb->list);
 371         cb->fp = fp;
 372         cb->cl = cl;
 373         cb->buf_idx = 0;
 374         cb->fop_type = type;
 375         return cb;
 376 }
 377
 378 /**
 379  * __mei_io_list_flush - removes and frees cbs belonging to cl.
 380  *
 381  * @list:  an instance of our list structure
 382  * @cl:    host client, can be NULL for flushing the whole list
 383  * @free:  whether to free the cbs
 384  */
 385 static void __mei_io_list_flush(struct mei_cl_cb *list,
 386                                 struct mei_cl *cl, bool free)
 387 {
 388         struct mei_cl_cb *cb, *next;
 389
 390         /* enable removing everything if no cl is specified */
 391         list_for_each_entry_safe(cb, next, &list->list, list) {
 392                 if (!cl || mei_cl_cmp_id(cl, cb->cl)) {
 393                         list_del_init(&cb->list);
 394                         if (free)
 395                                 mei_io_cb_free(cb);
 396                 }
 397         }
 398 }
 399
 400 /**
 401  * mei_io_list_flush - removes list entry belonging to cl.
 402  *
 403  * @list:  An instance of our list structure
 404  * @cl: host client
 405  */
 406 void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl)
 407 {
 408         __mei_io_list_flush(list, cl, false);
 409 }
 410
 411 /**
 412  * mei_io_list_free - removes cb belonging to cl and free them
 413  *
 414  * @list:  An instance of our list structure
 415  * @cl: host client
 416  */
 417 static inline void mei_io_list_free(struct mei_cl_cb *list, struct mei_cl *cl)
 418 {
 419         __mei_io_list_flush(list, cl, true);
 420 }
 421
 422 /**
 423  * mei_io_cb_alloc_buf - allocate callback buffer
 424  *
 425  * @cb: io callback structure
 426  * @length: size of the buffer
 427  *
 428  * Return: 0 on success
 429  *         -EINVAL if cb is NULL
 430  *         -ENOMEM if allocation failed
 431  */
 432 int mei_io_cb_alloc_buf(struct mei_cl_cb *cb, size_t length)
 433 {
 434         if (!cb)
 435                 return -EINVAL;
 436
 437         if (length == 0)
 438                 return 0;
 439
 440         cb->buf.data = kmalloc(length, GFP_KERNEL);
 441         if (!cb->buf.data)
 442                 return -ENOMEM;
 443         cb->buf.size = length;
 444         return 0;
 445 }
 446
 447 /**
 448  * mei_cl_alloc_cb - a convenient wrapper for allocating read cb
 449  *
 450  * @cl: host client
 451  * @length: size of the buffer
 452  * @type: operation type
 453  * @fp: associated file pointer (might be NULL)
 454  *
 455  * Return: cb on success and NULL on failure
 456  */
 457 struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
 458                                   enum mei_cb_file_ops type,
 459                                   const struct file *fp)
 460 {
 461         struct mei_cl_cb *cb;
 462
 463         cb = mei_io_cb_init(cl, type, fp);
 464         if (!cb)
 465                 return NULL;
 466
 467         if (mei_io_cb_alloc_buf(cb, length)) {
 468                 mei_io_cb_free(cb);
 469                 return NULL;
 470         }
 471
 472         return cb;
 473 }
 474
 475 /**
 476  * mei_cl_read_cb - find this cl's callback in the read list
 477  *     for a specific file
 478  *
 479  * @cl: host client
 480  * @fp: file pointer (matching cb file object), may be NULL
 481  *
 482  * Return: cb on success, NULL if cb is not found
 483  */
 484 struct mei_cl_cb *mei_cl_read_cb(const struct mei_cl *cl, const struct file *fp)
 485 {
 486         struct mei_cl_cb *cb;
 487
 488         list_for_each_entry(cb, &cl->rd_completed, list)
 489                 if (!fp || fp == cb->fp)
 490                         return cb;
 491
 492         return NULL;
 493 }
 494
 495 /**
 496  * mei_cl_read_cb_flush - free client's read pending and completed cbs
 497  *   for a specific file
 498  *
 499  * @cl: host client
 500  * @fp: file pointer (matching cb file object), may be NULL
 501  */
 502 void mei_cl_read_cb_flush(const struct mei_cl *cl, const struct file *fp)
 503 {
 504         struct mei_cl_cb *cb, *next;
 505
 506         list_for_each_entry_safe(cb, next, &cl->rd_completed, list)
 507                 if (!fp || fp == cb->fp)
 508                         mei_io_cb_free(cb);
 509
 510
 511         list_for_each_entry_safe(cb, next, &cl->rd_pending, list)
 512                 if (!fp || fp == cb->fp)
 513                         mei_io_cb_free(cb);
 514 }
 515
 516 /**
 517  * mei_cl_flush_queues - flushes queue lists belonging to cl.
 518  *
 519  * @cl: host client
 520  * @fp: file pointer (matching cb file object), may be NULL
 521  *
 522  * Return: 0 on success, -EINVAL if cl or cl->dev is NULL.
 523  */
 524 int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp)
 525 {
 526         struct mei_device *dev;
 527
 528         if (WARN_ON(!cl || !cl->dev))
 529                 return -EINVAL;
 530
 531         dev = cl->dev;
 532
 533         cl_dbg(dev, cl, "remove list entry belonging to cl\n");
 534         mei_io_list_free(&cl->dev->write_list, cl);
 535         mei_io_list_free(&cl->dev->write_waiting_list, cl);
 536         mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
 537         mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
 538         mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
 539
 540         mei_cl_read_cb_flush(cl, fp);
 541
 542         return 0;
 543 }
 544
 545
 546 /**
 547  * mei_cl_init - initializes cl.
 548  *
 549  * @cl: host client to be initialized
 550  * @dev: mei device
 551  */
 552 void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
 553 {
 554         memset(cl, 0, sizeof(struct mei_cl));
 555         init_waitqueue_head(&cl->wait);
 556         init_waitqueue_head(&cl->rx_wait);
 557         init_waitqueue_head(&cl->tx_wait);
 558         init_waitqueue_head(&cl->ev_wait);
 559         INIT_LIST_HEAD(&cl->rd_completed);
 560         INIT_LIST_HEAD(&cl->rd_pending);
 561         INIT_LIST_HEAD(&cl->link);
 562         cl->writing_state = MEI_IDLE;
 563         cl->state = MEI_FILE_INITIALIZING;
 564         cl->dev = dev;
 565 }
 566
 567 /**
 568  * mei_cl_allocate - allocates cl  structure and sets it up.
 569  *
 570  * @dev: mei device
 571  * Return:  The allocated file or NULL on failure
 572  */
 573 struct mei_cl *mei_cl_allocate(struct mei_device *dev)
 574 {
 575         struct mei_cl *cl;
 576
 577         cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
 578         if (!cl)
 579                 return NULL;
 580
 581         mei_cl_init(cl, dev);
 582
 583         return cl;
 584 }
 585
 586 /**
 587  * mei_cl_link - allocate host id in the host map
 588  *
 589  * @cl: host client
 590  *
 591  * Return: 0 on success
 592  *      -EINVAL on incorrect values
 593  *      -EMFILE if open count exceeded.
 594  */
 595 int mei_cl_link(struct mei_cl *cl)
 596 {
 597         struct mei_device *dev;
 598         long open_handle_count;
 599         int id;
 600
 601         if (WARN_ON(!cl || !cl->dev))
 602                 return -EINVAL;
 603
 604         dev = cl->dev;
 605
 606         id = find_first_zero_bit(dev->host_clients_map, MEI_CLIENTS_MAX);
 607         if (id >= MEI_CLIENTS_MAX) {
 608                 dev_err(dev->dev, "id exceeded %d", MEI_CLIENTS_MAX);
 609                 return -EMFILE;
 610         }
 611
 612         open_handle_count = dev->open_handle_count + dev->iamthif_open_count;
 613         if (open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
 614                 dev_err(dev->dev, "open_handle_count exceeded %d",
 615                         MEI_MAX_OPEN_HANDLE_COUNT);
 616                 return -EMFILE;
 617         }
 618
 619         dev->open_handle_count++;
 620
 621         cl->host_client_id = id;
 622         list_add_tail(&cl->link, &dev->file_list);
 623
 624         set_bit(id, dev->host_clients_map);
 625
 626         cl->state = MEI_FILE_INITIALIZING;
 627
 628         cl_dbg(dev, cl, "link cl\n");
 629         return 0;
 630 }
 631
 632 /**
 633  * mei_cl_unlink - remove host client from the list
 634  *
 635  * @cl: host client
 636  *
 637  * Return: always 0
 638  */
 639 int mei_cl_unlink(struct mei_cl *cl)
 640 {
 641         struct mei_device *dev;
 642
 643         /* don't shout on error exit path */
 644         if (!cl)
 645                 return 0;
 646
 647         /* amthif might not be initialized */
 648         if (!cl->dev)
 649                 return 0;
 650
 651         dev = cl->dev;
 652
 653         cl_dbg(dev, cl, "unlink client");
 654
 655         if (dev->open_handle_count > 0)
 656                 dev->open_handle_count--;
 657
 658         /* never clear the 0 bit */
 659         if (cl->host_client_id)
 660                 clear_bit(cl->host_client_id, dev->host_clients_map);
 661
 662         list_del_init(&cl->link);
 663
 664         cl->state = MEI_FILE_INITIALIZING;
 665
 666         return 0;
 667 }
 668
 669 void mei_host_client_init(struct mei_device *dev)
 670 {
 671         dev->dev_state = MEI_DEV_ENABLED;
 672         dev->reset_count = 0;
 673
 674         schedule_work(&dev->bus_rescan_work);
 675
 676         pm_runtime_mark_last_busy(dev->dev);
 677         dev_dbg(dev->dev, "rpm: autosuspend\n");
 678         pm_runtime_autosuspend(dev->dev);
 679 }
 680
 681 /**
 682  * mei_hbuf_acquire - try to acquire host buffer
 683  *
 684  * @dev: the device structure
 685  * Return: true if host buffer was acquired
 686  */
 687 bool mei_hbuf_acquire(struct mei_device *dev)
 688 {
 689         if (mei_pg_state(dev) == MEI_PG_ON ||
 690             mei_pg_in_transition(dev)) {
 691                 dev_dbg(dev->dev, "device is in pg\n");
 692                 return false;
 693         }
 694
 695         if (!dev->hbuf_is_ready) {
 696                 dev_dbg(dev->dev, "hbuf is not ready\n");
 697                 return false;
 698         }
 699
 700         dev->hbuf_is_ready = false;
 701
 702         return true;
 703 }
 704
 705 /**
 706  * mei_cl_wake_all - wake up readers, writers and event waiters so
 707  *                 they can be interrupted
 708  *
 709  * @cl: host client
 710  */
 711 static void mei_cl_wake_all(struct mei_cl *cl)
 712 {
 713         struct mei_device *dev = cl->dev;
 714
 715         /* synchronized under device mutex */
 716         if (waitqueue_active(&cl->rx_wait)) {
 717                 cl_dbg(dev, cl, "Waking up reading client!\n");
 718                 wake_up_interruptible(&cl->rx_wait);
 719         }
 720         /* synchronized under device mutex */
 721         if (waitqueue_active(&cl->tx_wait)) {
 722                 cl_dbg(dev, cl, "Waking up writing client!\n");
 723                 wake_up_interruptible(&cl->tx_wait);
 724         }
 725         /* synchronized under device mutex */
 726         if (waitqueue_active(&cl->ev_wait)) {
 727                 cl_dbg(dev, cl, "Waking up waiting for event clients!\n");
 728                 wake_up_interruptible(&cl->ev_wait);
 729         }
 730 }
 731
 732 /**
 733  * mei_cl_set_disconnected - set disconnected state and clear
 734  *   associated states and resources
 735  *
 736  * @cl: host client
 737  */
 738 void mei_cl_set_disconnected(struct mei_cl *cl)
 739 {
 740         struct mei_device *dev = cl->dev;
 741
 742         if (cl->state == MEI_FILE_DISCONNECTED ||
 743             cl->state == MEI_FILE_INITIALIZING)
 744                 return;
 745
 746         cl->state = MEI_FILE_DISCONNECTED;
 747         mei_io_list_free(&dev->write_list, cl);
 748         mei_io_list_free(&dev->write_waiting_list, cl);
 749         mei_io_list_flush(&dev->ctrl_rd_list, cl);
 750         mei_io_list_flush(&dev->ctrl_wr_list, cl);
 751         mei_cl_wake_all(cl);
 752         cl->mei_flow_ctrl_creds = 0;
 753         cl->timer_count = 0;
 754
 755         if (!cl->me_cl)
 756                 return;
 757
 758         if (!WARN_ON(cl->me_cl->connect_count == 0))
 759                 cl->me_cl->connect_count--;
 760
 761         if (cl->me_cl->connect_count == 0)
 762                 cl->me_cl->mei_flow_ctrl_creds = 0;
 763
 764         mei_me_cl_put(cl->me_cl);
 765         cl->me_cl = NULL;
 766 }
 767
 768 static int mei_cl_set_connecting(struct mei_cl *cl, struct mei_me_client *me_cl)
 769 {
 770         if (!mei_me_cl_get(me_cl))
 771                 return -ENOENT;
 772
 773         /* only one connection is allowed for fixed address clients */
 774         if (me_cl->props.fixed_address) {
 775                 if (me_cl->connect_count) {
 776                         mei_me_cl_put(me_cl);
 777                         return -EBUSY;
 778                 }
 779         }
 780
 781         cl->me_cl = me_cl;
 782         cl->state = MEI_FILE_CONNECTING;
 783         cl->me_cl->connect_count++;
 784
 785         return 0;
 786 }
 787
 788 /*
 789  * mei_cl_send_disconnect - send disconnect request
 790  *
 791  * @cl: host client
 792  * @cb: callback block
 793  *
 794  * Return: 0, OK; otherwise, error.
 795  */
 796 static int mei_cl_send_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb)
 797 {
 798         struct mei_device *dev;
 799         int ret;
 800
 801         dev = cl->dev;
 802
 803         ret = mei_hbm_cl_disconnect_req(dev, cl);
 804         cl->status = ret;
 805         if (ret) {
 806                 cl->state = MEI_FILE_DISCONNECT_REPLY;
 807                 return ret;
 808         }
 809
 810         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 811         cl->timer_count = MEI_CONNECT_TIMEOUT;
 812
 813         return 0;
 814 }
 815
 816 /**
 817  * mei_cl_irq_disconnect - processes close related operation from
 818  *      interrupt thread context - send disconnect request
 819  *
 820  * @cl: client
 821  * @cb: callback block.
 822  * @cmpl_list: complete list.
 823  *
 824  * Return: 0, OK; otherwise, error.
 825  */
 826 int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
 827                             struct mei_cl_cb *cmpl_list)
 828 {
 829         struct mei_device *dev = cl->dev;
 830         u32 msg_slots;
 831         int slots;
 832         int ret;
 833
 834         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 835         slots = mei_hbuf_empty_slots(dev);
 836
 837         if (slots < msg_slots)
 838                 return -EMSGSIZE;
 839
 840         ret = mei_cl_send_disconnect(cl, cb);
 841         if (ret)
 842                 list_move_tail(&cb->list, &cmpl_list->list);
 843
 844         return ret;
 845 }
 846
 847 /**
 848  * __mei_cl_disconnect - disconnect host client from the me one
 849  *     internal function runtime pm has to be already acquired
 850  *
 851  * @cl: host client
 852  *
 853  * Return: 0 on success, <0 on failure.
 854  */
 855 static int __mei_cl_disconnect(struct mei_cl *cl)
 856 {
 857         struct mei_device *dev;
 858         struct mei_cl_cb *cb;
 859         int rets;
 860
 861         dev = cl->dev;
 862
 863         cl->state = MEI_FILE_DISCONNECTING;
 864
 865         cb = mei_io_cb_init(cl, MEI_FOP_DISCONNECT, NULL);
 866         rets = cb ? 0 : -ENOMEM;
 867         if (rets)
 868                 goto out;
 869
 870         cl_dbg(dev, cl, "add disconnect cb to control write list\n");
 871         list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
 872
 873         if (mei_hbuf_acquire(dev)) {
 874                 rets = mei_cl_send_disconnect(cl, cb);
 875                 if (rets) {
 876                         cl_err(dev, cl, "failed to disconnect.\n");
 877                         goto out;
 878                 }
 879         }
 880
 881         mutex_unlock(&dev->device_lock);
 882         wait_event_timeout(cl->wait, cl->state == MEI_FILE_DISCONNECT_REPLY,
 883                            mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 884         mutex_lock(&dev->device_lock);
 885
 886         rets = cl->status;
 887         if (cl->state != MEI_FILE_DISCONNECT_REPLY) {
 888                 cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
 889                 rets = -ETIME;
 890         }
 891
 892 out:
 893         /* we disconnect also on error */
 894         mei_cl_set_disconnected(cl);
 895         if (!rets)
 896                 cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
 897
 898         mei_io_cb_free(cb);
 899         return rets;
 900 }
 901
 902 /**
 903  * mei_cl_disconnect - disconnect host client from the me one
 904  *
 905  * @cl: host client
 906  *
 907  * Locking: called under "dev->device_lock" lock
 908  *
 909  * Return: 0 on success, <0 on failure.
 910  */
 911 int mei_cl_disconnect(struct mei_cl *cl)
 912 {
 913         struct mei_device *dev;
 914         int rets;
 915
 916         if (WARN_ON(!cl || !cl->dev))
 917                 return -ENODEV;
 918
 919         dev = cl->dev;
 920
 921         cl_dbg(dev, cl, "disconnecting");
 922
 923         if (!mei_cl_is_connected(cl))
 924                 return 0;
 925
 926         if (mei_cl_is_fixed_address(cl)) {
 927                 mei_cl_set_disconnected(cl);
 928                 return 0;
 929         }
 930
 931         rets = pm_runtime_get(dev->dev);
 932         if (rets < 0 && rets != -EINPROGRESS) {
 933                 pm_runtime_put_noidle(dev->dev);
 934                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
 935                 return rets;
 936         }
 937
 938         rets = __mei_cl_disconnect(cl);
 939
 940         cl_dbg(dev, cl, "rpm: autosuspend\n");
 941         pm_runtime_mark_last_busy(dev->dev);
 942         pm_runtime_put_autosuspend(dev->dev);
 943
 944         return rets;
 945 }
 946
 947
 948 /**
 949  * mei_cl_is_other_connecting - checks if other
 950  *    client with the same me client id is connecting
 951  *
 952  * @cl: private data of the file object
 953  *
 954  * Return: true if other client is connected, false - otherwise.
 955  */
 956 static bool mei_cl_is_other_connecting(struct mei_cl *cl)
 957 {
 958         struct mei_device *dev;
 959         struct mei_cl_cb *cb;
 960
 961         dev = cl->dev;
 962
 963         list_for_each_entry(cb, &dev->ctrl_rd_list.list, list) {
 964                 if (cb->fop_type == MEI_FOP_CONNECT &&
 965                     mei_cl_me_id(cl) == mei_cl_me_id(cb->cl))
 966                         return true;
 967         }
 968
 969         return false;
 970 }
 971
 972 /**
 973  * mei_cl_send_connect - send connect request
 974  *
 975  * @cl: host client
 976  * @cb: callback block
 977  *
 978  * Return: 0, OK; otherwise, error.
 979  */
 980 static int mei_cl_send_connect(struct mei_cl *cl, struct mei_cl_cb *cb)
 981 {
 982         struct mei_device *dev;
 983         int ret;
 984
 985         dev = cl->dev;
 986
 987         ret = mei_hbm_cl_connect_req(dev, cl);
 988         cl->status = ret;
 989         if (ret) {
 990                 cl->state = MEI_FILE_DISCONNECT_REPLY;
 991                 return ret;
 992         }
 993
 994         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 995         cl->timer_count = MEI_CONNECT_TIMEOUT;
 996         return 0;
 997 }
 998
 999 /**
1000  * mei_cl_irq_connect - send connect request in irq_thread context
1001  *
1002  * @cl: host client
1003  * @cb: callback block
1004  * @cmpl_list: complete list
1005  *
1006  * Return: 0, OK; otherwise, error.
1007  */
1008 int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
1009                               struct mei_cl_cb *cmpl_list)
1010 {
1011         struct mei_device *dev = cl->dev;
1012         u32 msg_slots;
1013         int slots;
1014         int rets;
1015
1016         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1017         slots = mei_hbuf_empty_slots(dev);
1018
1019         if (mei_cl_is_other_connecting(cl))
1020                 return 0;
1021
1022         if (slots < msg_slots)
1023                 return -EMSGSIZE;
1024
1025         rets = mei_cl_send_connect(cl, cb);
1026         if (rets)
1027                 list_move_tail(&cb->list, &cmpl_list->list);
1028
1029         return rets;
1030 }
1031
1032 /**
1033  * mei_cl_connect - connect host client to the me one
1034  *
1035  * @cl: host client
1036  * @me_cl: me client
1037  * @file: pointer to file structure
1038  *
1039  * Locking: called under "dev->device_lock" lock
1040  *
1041  * Return: 0 on success, <0 on failure.
1042  */
1043 int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
1044                   const struct file *file)
1045 {
1046         struct mei_device *dev;
1047         struct mei_cl_cb *cb;
1048         int rets;
1049
1050         if (WARN_ON(!cl || !cl->dev || !me_cl))
1051                 return -ENODEV;
1052
1053         dev = cl->dev;
1054
1055         rets = mei_cl_set_connecting(cl, me_cl);
1056         if (rets)
1057                 return rets;
1058
1059         if (mei_cl_is_fixed_address(cl)) {
1060                 cl->state = MEI_FILE_CONNECTED;
1061                 return 0;
1062         }
1063
1064         rets = pm_runtime_get(dev->dev);
1065         if (rets < 0 && rets != -EINPROGRESS) {
1066                 pm_runtime_put_noidle(dev->dev);
1067                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1068                 goto nortpm;
1069         }
1070
1071         cb = mei_io_cb_init(cl, MEI_FOP_CONNECT, file);
1072         rets = cb ? 0 : -ENOMEM;
1073         if (rets)
1074                 goto out;
1075
1076         list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
1077
1078         /* run hbuf acquire last so we don't have to undo */
1079         if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
1080                 rets = mei_cl_send_connect(cl, cb);
1081                 if (rets)
1082                         goto out;
1083         }
1084
1085         mutex_unlock(&dev->device_lock);
1086         wait_event_timeout(cl->wait,
1087                         (cl->state == MEI_FILE_CONNECTED ||
1088                          cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
1089                          cl->state == MEI_FILE_DISCONNECT_REPLY),
1090                         mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1091         mutex_lock(&dev->device_lock);
1092
1093         if (!mei_cl_is_connected(cl)) {
1094                 if (cl->state == MEI_FILE_DISCONNECT_REQUIRED) {
1095                         mei_io_list_flush(&dev->ctrl_rd_list, cl);
1096                         mei_io_list_flush(&dev->ctrl_wr_list, cl);
1097                          /* ignore disconnect return valuue;
1098                           * in case of failure reset will be invoked
1099                           */
1100                         __mei_cl_disconnect(cl);
1101                         rets = -EFAULT;
1102                         goto out;
1103                 }
1104
1105                 /* timeout or something went really wrong */
1106                 if (!cl->status)
1107                         cl->status = -EFAULT;
1108         }
1109
1110         rets = cl->status;
1111 out:
1112         cl_dbg(dev, cl, "rpm: autosuspend\n");
1113         pm_runtime_mark_last_busy(dev->dev);
1114         pm_runtime_put_autosuspend(dev->dev);
1115
1116         mei_io_cb_free(cb);
1117
1118 nortpm:
1119         if (!mei_cl_is_connected(cl))
1120                 mei_cl_set_disconnected(cl);
1121
1122         return rets;
1123 }
1124
1125 /**
1126  * mei_cl_alloc_linked - allocate and link host client
1127  *
1128  * @dev: the device structure
1129  *
1130  * Return: cl on success ERR_PTR on failure
1131  */
1132 struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev)
1133 {
1134         struct mei_cl *cl;
1135         int ret;
1136
1137         cl = mei_cl_allocate(dev);
1138         if (!cl) {
1139                 ret = -ENOMEM;
1140                 goto err;
1141         }
1142
1143         ret = mei_cl_link(cl);
1144         if (ret)
1145                 goto err;
1146
1147         return cl;
1148 err:
1149         kfree(cl);
1150         return ERR_PTR(ret);
1151 }
1152
1153
1154
1155 /**
1156  * mei_cl_flow_ctrl_creds - checks flow_control credits for cl.
1157  *
1158  * @cl: host client
1159  * @fp: the file pointer associated with the pointer
1160  *
1161  * Return: 1 if mei_flow_ctrl_creds >0, 0 - otherwise.
1162  */
1163 static int mei_cl_flow_ctrl_creds(struct mei_cl *cl, const struct file *fp)
1164 {
1165         int rets;
1166
1167         if (WARN_ON(!cl || !cl->me_cl))
1168                 return -EINVAL;
1169
1170         if (cl->mei_flow_ctrl_creds > 0)
1171                 return 1;
1172
1173         if (mei_cl_is_fixed_address(cl)) {
1174                 rets = mei_cl_read_start(cl, mei_cl_mtu(cl), fp);
1175                 if (rets && rets != -EBUSY)
1176                         return rets;
1177                 return 1;
1178         }
1179
1180         if (mei_cl_is_single_recv_buf(cl)) {
1181                 if (cl->me_cl->mei_flow_ctrl_creds > 0)
1182                         return 1;
1183         }
1184         return 0;
1185 }
1186
1187 /**
1188  * mei_cl_flow_ctrl_reduce - reduces flow_control.
1189  *
1190  * @cl: private data of the file object
1191  *
1192  * Return:
1193  *      0 on success
1194  *      -EINVAL when ctrl credits are <= 0
1195  */
1196 static int mei_cl_flow_ctrl_reduce(struct mei_cl *cl)
1197 {
1198         if (WARN_ON(!cl || !cl->me_cl))
1199                 return -EINVAL;
1200
1201         if (mei_cl_is_fixed_address(cl))
1202                 return 0;
1203
1204         if (mei_cl_is_single_recv_buf(cl)) {
1205                 if (WARN_ON(cl->me_cl->mei_flow_ctrl_creds <= 0))
1206                         return -EINVAL;
1207                 cl->me_cl->mei_flow_ctrl_creds--;
1208         } else {
1209                 if (WARN_ON(cl->mei_flow_ctrl_creds <= 0))
1210                         return -EINVAL;
1211                 cl->mei_flow_ctrl_creds--;
1212         }
1213         return 0;
1214 }
1215
1216 /**
1217  *  mei_cl_notify_fop2req - convert fop to proper request
1218  *
1219  * @fop: client notification start response command
1220  *
1221  * Return:  MEI_HBM_NOTIFICATION_START/STOP
1222  */
1223 u8 mei_cl_notify_fop2req(enum mei_cb_file_ops fop)
1224 {
1225         if (fop == MEI_FOP_NOTIFY_START)
1226                 return MEI_HBM_NOTIFICATION_START;
1227         else
1228                 return MEI_HBM_NOTIFICATION_STOP;
1229 }
1230
1231 /**
1232  *  mei_cl_notify_req2fop - convert notification request top file operation type
1233  *
1234  * @req: hbm notification request type
1235  *
1236  * Return:  MEI_FOP_NOTIFY_START/STOP
1237  */
1238 enum mei_cb_file_ops mei_cl_notify_req2fop(u8 req)
1239 {
1240         if (req == MEI_HBM_NOTIFICATION_START)
1241                 return MEI_FOP_NOTIFY_START;
1242         else
1243                 return MEI_FOP_NOTIFY_STOP;
1244 }
1245
1246 /**
1247  * mei_cl_irq_notify - send notification request in irq_thread context
1248  *
1249  * @cl: client
1250  * @cb: callback block.
1251  * @cmpl_list: complete list.
1252  *
1253  * Return: 0 on such and error otherwise.
1254  */
1255 int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
1256                       struct mei_cl_cb *cmpl_list)
1257 {
1258         struct mei_device *dev = cl->dev;
1259         u32 msg_slots;
1260         int slots;
1261         int ret;
1262         bool request;
1263
1264         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1265         slots = mei_hbuf_empty_slots(dev);
1266
1267         if (slots < msg_slots)
1268                 return -EMSGSIZE;
1269
1270         request = mei_cl_notify_fop2req(cb->fop_type);
1271         ret = mei_hbm_cl_notify_req(dev, cl, request);
1272         if (ret) {
1273                 cl->status = ret;
1274                 list_move_tail(&cb->list, &cmpl_list->list);
1275                 return ret;
1276         }
1277
1278         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
1279         return 0;
1280 }
1281
1282 /**
1283  * mei_cl_notify_request - send notification stop/start request
1284  *
1285  * @cl: host client
1286  * @file: associate request with file
1287  * @request: 1 for start or 0 for stop
1288  *
1289  * Locking: called under "dev->device_lock" lock
1290  *
1291  * Return: 0 on such and error otherwise.
1292  */
1293 int mei_cl_notify_request(struct mei_cl *cl,
1294                           const struct file *file, u8 request)
1295 {
1296         struct mei_device *dev;
1297         struct mei_cl_cb *cb;
1298         enum mei_cb_file_ops fop_type;
1299         int rets;
1300
1301         if (WARN_ON(!cl || !cl->dev))
1302                 return -ENODEV;
1303
1304         dev = cl->dev;
1305
1306         if (!dev->hbm_f_ev_supported) {
1307                 cl_dbg(dev, cl, "notifications not supported\n");
1308                 return -EOPNOTSUPP;
1309         }
1310
1311         rets = pm_runtime_get(dev->dev);
1312         if (rets < 0 && rets != -EINPROGRESS) {
1313                 pm_runtime_put_noidle(dev->dev);
1314                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1315                 return rets;
1316         }
1317
1318         fop_type = mei_cl_notify_req2fop(request);
1319         cb = mei_io_cb_init(cl, fop_type, file);
1320         if (!cb) {
1321                 rets = -ENOMEM;
1322                 goto out;
1323         }
1324
1325         if (mei_hbuf_acquire(dev)) {
1326                 if (mei_hbm_cl_notify_req(dev, cl, request)) {
1327                         rets = -ENODEV;
1328                         goto out;
1329                 }
1330                 list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
1331         } else {
1332                 list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
1333         }
1334
1335         mutex_unlock(&dev->device_lock);
1336         wait_event_timeout(cl->wait, cl->notify_en == request,
1337                         mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1338         mutex_lock(&dev->device_lock);
1339
1340         if (cl->notify_en != request) {
1341                 mei_io_list_flush(&dev->ctrl_rd_list, cl);
1342                 mei_io_list_flush(&dev->ctrl_wr_list, cl);
1343                 if (!cl->status)
1344                         cl->status = -EFAULT;
1345         }
1346
1347         rets = cl->status;
1348
1349 out:
1350         cl_dbg(dev, cl, "rpm: autosuspend\n");
1351         pm_runtime_mark_last_busy(dev->dev);
1352         pm_runtime_put_autosuspend(dev->dev);
1353
1354         mei_io_cb_free(cb);
1355         return rets;
1356 }
1357
1358 /**
1359  * mei_cl_notify - raise notification
1360  *
1361  * @cl: host client
1362  *
1363  * Locking: called under "dev->device_lock" lock
1364  */
1365 void mei_cl_notify(struct mei_cl *cl)
1366 {
1367         struct mei_device *dev;
1368
1369         if (!cl || !cl->dev)
1370                 return;
1371
1372         dev = cl->dev;
1373
1374         if (!cl->notify_en)
1375                 return;
1376
1377         cl_dbg(dev, cl, "notify event");
1378         cl->notify_ev = true;
1379         if (!mei_cl_bus_notify_event(cl))
1380                 wake_up_interruptible(&cl->ev_wait);
1381
1382         if (cl->ev_async)
1383                 kill_fasync(&cl->ev_async, SIGIO, POLL_PRI);
1384
1385 }
1386
1387 /**
1388  * mei_cl_notify_get - get or wait for notification event
1389  *
1390  * @cl: host client
1391  * @block: this request is blocking
1392  * @notify_ev: true if notification event was received
1393  *
1394  * Locking: called under "dev->device_lock" lock
1395  *
1396  * Return: 0 on such and error otherwise.
1397  */
1398 int mei_cl_notify_get(struct mei_cl *cl, bool block, bool *notify_ev)
1399 {
1400         struct mei_device *dev;
1401         int rets;
1402
1403         *notify_ev = false;
1404
1405         if (WARN_ON(!cl || !cl->dev))
1406                 return -ENODEV;
1407
1408         dev = cl->dev;
1409
1410         if (!mei_cl_is_connected(cl))
1411                 return -ENODEV;
1412
1413         if (cl->notify_ev)
1414                 goto out;
1415
1416         if (!block)
1417                 return -EAGAIN;
1418
1419         mutex_unlock(&dev->device_lock);
1420         rets = wait_event_interruptible(cl->ev_wait, cl->notify_ev);
1421         mutex_lock(&dev->device_lock);
1422
1423         if (rets < 0)
1424                 return rets;
1425
1426 out:
1427         *notify_ev = cl->notify_ev;
1428         cl->notify_ev = false;
1429         return 0;
1430 }
1431
1432 /**
1433  * mei_cl_is_read_fc_cb - check if read cb is waiting for flow control
1434  *                        for given host client
1435  *
1436  * @cl: host client
1437  *
1438  * Return: true, if found at least one cb.
1439  */
1440 static bool mei_cl_is_read_fc_cb(struct mei_cl *cl)
1441 {
1442         struct mei_device *dev = cl->dev;
1443         struct mei_cl_cb *cb;
1444
1445         list_for_each_entry(cb, &dev->ctrl_wr_list.list, list)
1446                 if (cb->fop_type == MEI_FOP_READ && cb->cl == cl)
1447                         return true;
1448         return false;
1449 }
1450
1451 /**
1452  * mei_cl_read_start - the start read client message function.
1453  *
1454  * @cl: host client
1455  * @length: number of bytes to read
1456  * @fp: pointer to file structure
1457  *
1458  * Return: 0 on success, <0 on failure.
1459  */
1460 int mei_cl_read_start(struct mei_cl *cl, size_t length, const struct file *fp)
1461 {
1462         struct mei_device *dev;
1463         struct mei_cl_cb *cb;
1464         int rets;
1465
1466         if (WARN_ON(!cl || !cl->dev))
1467                 return -ENODEV;
1468
1469         dev = cl->dev;
1470
1471         if (!mei_cl_is_connected(cl))
1472                 return -ENODEV;
1473
1474         /* HW currently supports only one pending read */
1475         if (!list_empty(&cl->rd_pending) || mei_cl_is_read_fc_cb(cl))
1476                 return -EBUSY;
1477
1478         if (!mei_me_cl_is_active(cl->me_cl)) {
1479                 cl_err(dev, cl, "no such me client\n");
1480                 return  -ENOTTY;
1481         }
1482
1483         /* always allocate at least client max message */
1484         length = max_t(size_t, length, mei_cl_mtu(cl));
1485         cb = mei_cl_alloc_cb(cl, length, MEI_FOP_READ, fp);
1486         if (!cb)
1487                 return -ENOMEM;
1488
1489         if (mei_cl_is_fixed_address(cl)) {
1490                 list_add_tail(&cb->list, &cl->rd_pending);
1491                 return 0;
1492         }
1493
1494         rets = pm_runtime_get(dev->dev);
1495         if (rets < 0 && rets != -EINPROGRESS) {
1496                 pm_runtime_put_noidle(dev->dev);
1497                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1498                 goto nortpm;
1499         }
1500
1501         if (mei_hbuf_acquire(dev)) {
1502                 rets = mei_hbm_cl_flow_control_req(dev, cl);
1503                 if (rets < 0)
1504                         goto out;
1505
1506                 list_add_tail(&cb->list, &cl->rd_pending);
1507         } else {
1508                 rets = 0;
1509                 list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
1510         }
1511
1512 out:
1513         cl_dbg(dev, cl, "rpm: autosuspend\n");
1514         pm_runtime_mark_last_busy(dev->dev);
1515         pm_runtime_put_autosuspend(dev->dev);
1516 nortpm:
1517         if (rets)
1518                 mei_io_cb_free(cb);
1519
1520         return rets;
1521 }
1522
1523 /**
1524  * mei_cl_irq_write - write a message to device
1525  *      from the interrupt thread context
1526  *
1527  * @cl: client
1528  * @cb: callback block.
1529  * @cmpl_list: complete list.
1530  *
1531  * Return: 0, OK; otherwise error.
1532  */
1533 int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
1534                      struct mei_cl_cb *cmpl_list)
1535 {
1536         struct mei_device *dev;
1537         struct mei_msg_data *buf;
1538         struct mei_msg_hdr mei_hdr;
1539         size_t len;
1540         u32 msg_slots;
1541         int slots;
1542         int rets;
1543         bool first_chunk;
1544
1545         if (WARN_ON(!cl || !cl->dev))
1546                 return -ENODEV;
1547
1548         dev = cl->dev;
1549
1550         buf = &cb->buf;
1551
1552         first_chunk = cb->buf_idx == 0;
1553
1554         rets = first_chunk ? mei_cl_flow_ctrl_creds(cl, cb->fp) : 1;
1555         if (rets < 0)
1556                 return rets;
1557
1558         if (rets == 0) {
1559                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1560                 return 0;
1561         }
1562
1563         slots = mei_hbuf_empty_slots(dev);
1564         len = buf->size - cb->buf_idx;
1565         msg_slots = mei_data2slots(len);
1566
1567         mei_hdr.host_addr = mei_cl_host_addr(cl);
1568         mei_hdr.me_addr = mei_cl_me_id(cl);
1569         mei_hdr.reserved = 0;
1570         mei_hdr.internal = cb->internal;
1571
1572         if (slots >= msg_slots) {
1573                 mei_hdr.length = len;
1574                 mei_hdr.msg_complete = 1;
1575         /* Split the message only if we can write the whole host buffer */
1576         } else if (slots == dev->hbuf_depth) {
1577                 msg_slots = slots;
1578                 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
1579                 mei_hdr.length = len;
1580                 mei_hdr.msg_complete = 0;
1581         } else {
1582                 /* wait for next time the host buffer is empty */
1583                 return 0;
1584         }
1585
1586         cl_dbg(dev, cl, "buf: size = %zu idx = %zu\n",
1587                         cb->buf.size, cb->buf_idx);
1588
1589         rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
1590         if (rets) {
1591                 cl->status = rets;
1592                 list_move_tail(&cb->list, &cmpl_list->list);
1593                 return rets;
1594         }
1595
1596         cl->status = 0;
1597         cl->writing_state = MEI_WRITING;
1598         cb->buf_idx += mei_hdr.length;
1599         cb->completed = mei_hdr.msg_complete == 1;
1600
1601         if (first_chunk) {
1602                 if (mei_cl_flow_ctrl_reduce(cl))
1603                         return -EIO;
1604         }
1605
1606         if (mei_hdr.msg_complete)
1607                 list_move_tail(&cb->list, &dev->write_waiting_list.list);
1608
1609         return 0;
1610 }
1611
1612 /**
1613  * mei_cl_write - submit a write cb to mei device
1614  *      assumes device_lock is locked
1615  *
1616  * @cl: host client
1617  * @cb: write callback with filled data
1618  * @blocking: block until completed
1619  *
1620  * Return: number of bytes sent on success, <0 on failure.
1621  */
1622 int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking)
1623 {
1624         struct mei_device *dev;
1625         struct mei_msg_data *buf;
1626         struct mei_msg_hdr mei_hdr;
1627         int size;
1628         int rets;
1629
1630
1631         if (WARN_ON(!cl || !cl->dev))
1632                 return -ENODEV;
1633
1634         if (WARN_ON(!cb))
1635                 return -EINVAL;
1636
1637         dev = cl->dev;
1638
1639         buf = &cb->buf;
1640         size = buf->size;
1641
1642         cl_dbg(dev, cl, "size=%d\n", size);
1643
1644         rets = pm_runtime_get(dev->dev);
1645         if (rets < 0 && rets != -EINPROGRESS) {
1646                 pm_runtime_put_noidle(dev->dev);
1647                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1648                 goto free;
1649         }
1650
1651         cb->buf_idx = 0;
1652         cl->writing_state = MEI_IDLE;
1653
1654         mei_hdr.host_addr = mei_cl_host_addr(cl);
1655         mei_hdr.me_addr = mei_cl_me_id(cl);
1656         mei_hdr.reserved = 0;
1657         mei_hdr.msg_complete = 0;
1658         mei_hdr.internal = cb->internal;
1659
1660         rets = mei_cl_flow_ctrl_creds(cl, cb->fp);
1661         if (rets < 0)
1662                 goto err;
1663
1664         if (rets == 0) {
1665                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1666                 rets = size;
1667                 goto out;
1668         }
1669         if (!mei_hbuf_acquire(dev)) {
1670                 cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
1671                 rets = size;
1672                 goto out;
1673         }
1674
1675         /* Check for a maximum length */
1676         if (size > mei_hbuf_max_len(dev)) {
1677                 mei_hdr.length = mei_hbuf_max_len(dev);
1678                 mei_hdr.msg_complete = 0;
1679         } else {
1680                 mei_hdr.length = size;
1681                 mei_hdr.msg_complete = 1;
1682         }
1683
1684         rets = mei_write_message(dev, &mei_hdr, buf->data);
1685         if (rets)
1686                 goto err;
1687
1688         rets = mei_cl_flow_ctrl_reduce(cl);
1689         if (rets)
1690                 goto err;
1691
1692         cl->writing_state = MEI_WRITING;
1693         cb->buf_idx = mei_hdr.length;
1694         cb->completed = mei_hdr.msg_complete == 1;
1695
1696 out:
1697         if (mei_hdr.msg_complete)
1698                 list_add_tail(&cb->list, &dev->write_waiting_list.list);
1699         else
1700                 list_add_tail(&cb->list, &dev->write_list.list);
1701
1702         cb = NULL;
1703         if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
1704
1705                 mutex_unlock(&dev->device_lock);
1706                 rets = wait_event_interruptible(cl->tx_wait,
1707                                 cl->writing_state == MEI_WRITE_COMPLETE ||
1708                                 (!mei_cl_is_connected(cl)));
1709                 mutex_lock(&dev->device_lock);
1710                 /* wait_event_interruptible returns -ERESTARTSYS */
1711                 if (rets) {
1712                         if (signal_pending(current))
1713                                 rets = -EINTR;
1714                         goto err;
1715                 }
1716                 if (cl->writing_state != MEI_WRITE_COMPLETE) {
1717                         rets = -EFAULT;
1718                         goto err;
1719                 }
1720         }
1721
1722         rets = size;
1723 err:
1724         cl_dbg(dev, cl, "rpm: autosuspend\n");
1725         pm_runtime_mark_last_busy(dev->dev);
1726         pm_runtime_put_autosuspend(dev->dev);
1727 free:
1728         mei_io_cb_free(cb);
1729
1730         return rets;
1731 }
1732
1733
1734 /**
1735  * mei_cl_complete - processes completed operation for a client
1736  *
1737  * @cl: private data of the file object.
1738  * @cb: callback block.
1739  */
1740 void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
1741 {
1742         struct mei_device *dev = cl->dev;
1743
1744         switch (cb->fop_type) {
1745         case MEI_FOP_WRITE:
1746                 mei_io_cb_free(cb);
1747                 cl->writing_state = MEI_WRITE_COMPLETE;
1748                 if (waitqueue_active(&cl->tx_wait)) {
1749                         wake_up_interruptible(&cl->tx_wait);
1750                 } else {
1751                         pm_runtime_mark_last_busy(dev->dev);
1752                         pm_request_autosuspend(dev->dev);
1753                 }
1754                 break;
1755
1756         case MEI_FOP_READ:
1757                 list_add_tail(&cb->list, &cl->rd_completed);
1758                 if (!mei_cl_bus_rx_event(cl))
1759                         wake_up_interruptible(&cl->rx_wait);
1760                 break;
1761
1762         case MEI_FOP_CONNECT:
1763         case MEI_FOP_DISCONNECT:
1764         case MEI_FOP_NOTIFY_STOP:
1765         case MEI_FOP_NOTIFY_START:
1766                 if (waitqueue_active(&cl->wait))
1767                         wake_up(&cl->wait);
1768
1769                 break;
1770         default:
1771                 BUG_ON(0);
1772         }
1773 }
1774
1775
1776 /**
1777  * mei_cl_all_disconnect - disconnect forcefully all connected clients
1778  *
1779  * @dev: mei device
1780  */
1781 void mei_cl_all_disconnect(struct mei_device *dev)
1782 {
1783         struct mei_cl *cl;
1784
1785         list_for_each_entry(cl, &dev->file_list, link)
1786                 mei_cl_set_disconnected(cl);
1787 }