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/signal.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_cl - removes and frees cbs belonging to cl.
 381  *
 382  * @head:  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_cl(struct list_head *head,
 387                                    const 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, head, 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_cl - removes list entry belonging to cl.
 403  *
 404  * @head: An instance of our list structure
 405  * @cl: host client
 406  */
 407 static inline void mei_io_list_flush_cl(struct list_head *head,
 408                                         const struct mei_cl *cl)
 409 {
 410         __mei_io_list_flush_cl(head, cl, false);
 411 }
 412
 413 /**
 414  * mei_io_list_free_cl - removes cb belonging to cl and free them
 415  *
 416  * @head: An instance of our list structure
 417  * @cl: host client
 418  */
 419 static inline void mei_io_list_free_cl(struct list_head *head,
 420                                        const struct mei_cl *cl)
 421 {
 422         __mei_io_list_flush_cl(head, cl, true);
 423 }
 424
 425 /**
 426  * mei_io_list_free_fp - free cb from a list that matches file pointer
 427  *
 428  * @head: io list
 429  * @fp: file pointer (matching cb file object), may be NULL
 430  */
 431 static void mei_io_list_free_fp(struct list_head *head, const struct file *fp)
 432 {
 433         struct mei_cl_cb *cb, *next;
 434
 435         list_for_each_entry_safe(cb, next, head, list)
 436                 if (!fp || fp == cb->fp)
 437                         mei_io_cb_free(cb);
 438 }
 439
 440 /**
 441  * mei_cl_alloc_cb - a convenient wrapper for allocating read cb
 442  *
 443  * @cl: host client
 444  * @length: size of the buffer
 445  * @fop_type: operation type
 446  * @fp: associated file pointer (might be NULL)
 447  *
 448  * Return: cb on success and NULL on failure
 449  */
 450 struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
 451                                   enum mei_cb_file_ops fop_type,
 452                                   const struct file *fp)
 453 {
 454         struct mei_cl_cb *cb;
 455
 456         cb = mei_io_cb_init(cl, fop_type, fp);
 457         if (!cb)
 458                 return NULL;
 459
 460         if (length == 0)
 461                 return cb;
 462
 463         cb->buf.data = kmalloc(length, GFP_KERNEL);
 464         if (!cb->buf.data) {
 465                 mei_io_cb_free(cb);
 466                 return NULL;
 467         }
 468         cb->buf.size = length;
 469
 470         return cb;
 471 }
 472
 473 /**
 474  * mei_cl_enqueue_ctrl_wr_cb - a convenient wrapper for allocating
 475  *     and enqueuing of the control commands cb
 476  *
 477  * @cl: host client
 478  * @length: size of the buffer
 479  * @fop_type: operation type
 480  * @fp: associated file pointer (might be NULL)
 481  *
 482  * Return: cb on success and NULL on failure
 483  * Locking: called under "dev->device_lock" lock
 484  */
 485 struct mei_cl_cb *mei_cl_enqueue_ctrl_wr_cb(struct mei_cl *cl, size_t length,
 486                                             enum mei_cb_file_ops fop_type,
 487                                             const struct file *fp)
 488 {
 489         struct mei_cl_cb *cb;
 490
 491         /* for RX always allocate at least client's mtu */
 492         if (length)
 493                 length = max_t(size_t, length, mei_cl_mtu(cl));
 494
 495         cb = mei_cl_alloc_cb(cl, length, fop_type, fp);
 496         if (!cb)
 497                 return NULL;
 498
 499         list_add_tail(&cb->list, &cl->dev->ctrl_wr_list);
 500         return cb;
 501 }
 502
 503 /**
 504  * mei_cl_read_cb - find this cl's callback in the read list
 505  *     for a specific file
 506  *
 507  * @cl: host client
 508  * @fp: file pointer (matching cb file object), may be NULL
 509  *
 510  * Return: cb on success, NULL if cb is not found
 511  */
 512 struct mei_cl_cb *mei_cl_read_cb(const struct mei_cl *cl, const struct file *fp)
 513 {
 514         struct mei_cl_cb *cb;
 515
 516         list_for_each_entry(cb, &cl->rd_completed, list)
 517                 if (!fp || fp == cb->fp)
 518                         return cb;
 519
 520         return NULL;
 521 }
 522
 523 /**
 524  * mei_cl_flush_queues - flushes queue lists belonging to cl.
 525  *
 526  * @cl: host client
 527  * @fp: file pointer (matching cb file object), may be NULL
 528  *
 529  * Return: 0 on success, -EINVAL if cl or cl->dev is NULL.
 530  */
 531 int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp)
 532 {
 533         struct mei_device *dev;
 534
 535         if (WARN_ON(!cl || !cl->dev))
 536                 return -EINVAL;
 537
 538         dev = cl->dev;
 539
 540         cl_dbg(dev, cl, "remove list entry belonging to cl\n");
 541         mei_io_list_free_cl(&cl->dev->write_list, cl);
 542         mei_io_list_free_cl(&cl->dev->write_waiting_list, cl);
 543         mei_io_list_flush_cl(&cl->dev->ctrl_wr_list, cl);
 544         mei_io_list_flush_cl(&cl->dev->ctrl_rd_list, cl);
 545         mei_io_list_free_fp(&cl->rd_pending, fp);
 546         mei_io_list_free_fp(&cl->rd_completed, fp);
 547
 548         return 0;
 549 }
 550
 551 /**
 552  * mei_cl_init - initializes cl.
 553  *
 554  * @cl: host client to be initialized
 555  * @dev: mei device
 556  */
 557 static void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
 558 {
 559         memset(cl, 0, sizeof(struct mei_cl));
 560         init_waitqueue_head(&cl->wait);
 561         init_waitqueue_head(&cl->rx_wait);
 562         init_waitqueue_head(&cl->tx_wait);
 563         init_waitqueue_head(&cl->ev_wait);
 564         INIT_LIST_HEAD(&cl->rd_completed);
 565         INIT_LIST_HEAD(&cl->rd_pending);
 566         INIT_LIST_HEAD(&cl->link);
 567         cl->writing_state = MEI_IDLE;
 568         cl->state = MEI_FILE_UNINITIALIZED;
 569         cl->dev = dev;
 570 }
 571
 572 /**
 573  * mei_cl_allocate - allocates cl  structure and sets it up.
 574  *
 575  * @dev: mei device
 576  * Return:  The allocated file or NULL on failure
 577  */
 578 struct mei_cl *mei_cl_allocate(struct mei_device *dev)
 579 {
 580         struct mei_cl *cl;
 581
 582         cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
 583         if (!cl)
 584                 return NULL;
 585
 586         mei_cl_init(cl, dev);
 587
 588         return cl;
 589 }
 590
 591 /**
 592  * mei_cl_link - allocate host id in the host map
 593  *
 594  * @cl: host client
 595  *
 596  * Return: 0 on success
 597  *      -EINVAL on incorrect values
 598  *      -EMFILE if open count exceeded.
 599  */
 600 int mei_cl_link(struct mei_cl *cl)
 601 {
 602         struct mei_device *dev;
 603         int id;
 604
 605         if (WARN_ON(!cl || !cl->dev))
 606                 return -EINVAL;
 607
 608         dev = cl->dev;
 609
 610         id = find_first_zero_bit(dev->host_clients_map, MEI_CLIENTS_MAX);
 611         if (id >= MEI_CLIENTS_MAX) {
 612                 dev_err(dev->dev, "id exceeded %d", MEI_CLIENTS_MAX);
 613                 return -EMFILE;
 614         }
 615
 616         if (dev->open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
 617                 dev_err(dev->dev, "open_handle_count exceeded %d",
 618                         MEI_MAX_OPEN_HANDLE_COUNT);
 619                 return -EMFILE;
 620         }
 621
 622         dev->open_handle_count++;
 623
 624         cl->host_client_id = id;
 625         list_add_tail(&cl->link, &dev->file_list);
 626
 627         set_bit(id, dev->host_clients_map);
 628
 629         cl->state = MEI_FILE_INITIALIZING;
 630
 631         cl_dbg(dev, cl, "link cl\n");
 632         return 0;
 633 }
 634
 635 /**
 636  * mei_cl_unlink - remove host client from the list
 637  *
 638  * @cl: host client
 639  *
 640  * Return: always 0
 641  */
 642 int mei_cl_unlink(struct mei_cl *cl)
 643 {
 644         struct mei_device *dev;
 645
 646         /* don't shout on error exit path */
 647         if (!cl)
 648                 return 0;
 649
 650         if (WARN_ON(!cl->dev))
 651                 return 0;
 652
 653         dev = cl->dev;
 654
 655         cl_dbg(dev, cl, "unlink client");
 656
 657         if (dev->open_handle_count > 0)
 658                 dev->open_handle_count--;
 659
 660         /* never clear the 0 bit */
 661         if (cl->host_client_id)
 662                 clear_bit(cl->host_client_id, dev->host_clients_map);
 663
 664         list_del_init(&cl->link);
 665
 666         cl->state = MEI_FILE_UNINITIALIZED;
 667         cl->writing_state = MEI_IDLE;
 668
 669         WARN_ON(!list_empty(&cl->rd_completed) ||
 670                 !list_empty(&cl->rd_pending) ||
 671                 !list_empty(&cl->link));
 672
 673         return 0;
 674 }
 675
 676 void mei_host_client_init(struct mei_device *dev)
 677 {
 678         dev->dev_state = MEI_DEV_ENABLED;
 679         dev->reset_count = 0;
 680
 681         schedule_work(&dev->bus_rescan_work);
 682
 683         pm_runtime_mark_last_busy(dev->dev);
 684         dev_dbg(dev->dev, "rpm: autosuspend\n");
 685         pm_request_autosuspend(dev->dev);
 686 }
 687
 688 /**
 689  * mei_hbuf_acquire - try to acquire host buffer
 690  *
 691  * @dev: the device structure
 692  * Return: true if host buffer was acquired
 693  */
 694 bool mei_hbuf_acquire(struct mei_device *dev)
 695 {
 696         if (mei_pg_state(dev) == MEI_PG_ON ||
 697             mei_pg_in_transition(dev)) {
 698                 dev_dbg(dev->dev, "device is in pg\n");
 699                 return false;
 700         }
 701
 702         if (!dev->hbuf_is_ready) {
 703                 dev_dbg(dev->dev, "hbuf is not ready\n");
 704                 return false;
 705         }
 706
 707         dev->hbuf_is_ready = false;
 708
 709         return true;
 710 }
 711
 712 /**
 713  * mei_cl_wake_all - wake up readers, writers and event waiters so
 714  *                 they can be interrupted
 715  *
 716  * @cl: host client
 717  */
 718 static void mei_cl_wake_all(struct mei_cl *cl)
 719 {
 720         struct mei_device *dev = cl->dev;
 721
 722         /* synchronized under device mutex */
 723         if (waitqueue_active(&cl->rx_wait)) {
 724                 cl_dbg(dev, cl, "Waking up reading client!\n");
 725                 wake_up_interruptible(&cl->rx_wait);
 726         }
 727         /* synchronized under device mutex */
 728         if (waitqueue_active(&cl->tx_wait)) {
 729                 cl_dbg(dev, cl, "Waking up writing client!\n");
 730                 wake_up_interruptible(&cl->tx_wait);
 731         }
 732         /* synchronized under device mutex */
 733         if (waitqueue_active(&cl->ev_wait)) {
 734                 cl_dbg(dev, cl, "Waking up waiting for event clients!\n");
 735                 wake_up_interruptible(&cl->ev_wait);
 736         }
 737         /* synchronized under device mutex */
 738         if (waitqueue_active(&cl->wait)) {
 739                 cl_dbg(dev, cl, "Waking up ctrl write clients!\n");
 740                 wake_up(&cl->wait);
 741         }
 742 }
 743
 744 /**
 745  * mei_cl_set_disconnected - set disconnected state and clear
 746  *   associated states and resources
 747  *
 748  * @cl: host client
 749  */
 750 static void mei_cl_set_disconnected(struct mei_cl *cl)
 751 {
 752         struct mei_device *dev = cl->dev;
 753
 754         if (cl->state == MEI_FILE_DISCONNECTED ||
 755             cl->state <= MEI_FILE_INITIALIZING)
 756                 return;
 757
 758         cl->state = MEI_FILE_DISCONNECTED;
 759         mei_io_list_free_cl(&dev->write_list, cl);
 760         mei_io_list_free_cl(&dev->write_waiting_list, cl);
 761         mei_io_list_flush_cl(&dev->ctrl_rd_list, cl);
 762         mei_io_list_flush_cl(&dev->ctrl_wr_list, cl);
 763         mei_cl_wake_all(cl);
 764         cl->rx_flow_ctrl_creds = 0;
 765         cl->tx_flow_ctrl_creds = 0;
 766         cl->timer_count = 0;
 767
 768         mei_cl_bus_module_put(cl);
 769
 770         if (!cl->me_cl)
 771                 return;
 772
 773         if (!WARN_ON(cl->me_cl->connect_count == 0))
 774                 cl->me_cl->connect_count--;
 775
 776         if (cl->me_cl->connect_count == 0)
 777                 cl->me_cl->tx_flow_ctrl_creds = 0;
 778
 779         mei_me_cl_put(cl->me_cl);
 780         cl->me_cl = NULL;
 781 }
 782
 783 static int mei_cl_set_connecting(struct mei_cl *cl, struct mei_me_client *me_cl)
 784 {
 785         if (!mei_me_cl_get(me_cl))
 786                 return -ENOENT;
 787
 788         /* only one connection is allowed for fixed address clients */
 789         if (me_cl->props.fixed_address) {
 790                 if (me_cl->connect_count) {
 791                         mei_me_cl_put(me_cl);
 792                         return -EBUSY;
 793                 }
 794         }
 795
 796         cl->me_cl = me_cl;
 797         cl->state = MEI_FILE_CONNECTING;
 798         cl->me_cl->connect_count++;
 799
 800         return 0;
 801 }
 802
 803 /*
 804  * mei_cl_send_disconnect - send disconnect request
 805  *
 806  * @cl: host client
 807  * @cb: callback block
 808  *
 809  * Return: 0, OK; otherwise, error.
 810  */
 811 static int mei_cl_send_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb)
 812 {
 813         struct mei_device *dev;
 814         int ret;
 815
 816         dev = cl->dev;
 817
 818         ret = mei_hbm_cl_disconnect_req(dev, cl);
 819         cl->status = ret;
 820         if (ret) {
 821                 cl->state = MEI_FILE_DISCONNECT_REPLY;
 822                 return ret;
 823         }
 824
 825         list_move_tail(&cb->list, &dev->ctrl_rd_list);
 826         cl->timer_count = MEI_CONNECT_TIMEOUT;
 827         mei_schedule_stall_timer(dev);
 828
 829         return 0;
 830 }
 831
 832 /**
 833  * mei_cl_irq_disconnect - processes close related operation from
 834  *      interrupt thread context - send disconnect request
 835  *
 836  * @cl: client
 837  * @cb: callback block.
 838  * @cmpl_list: complete list.
 839  *
 840  * Return: 0, OK; otherwise, error.
 841  */
 842 int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
 843                           struct list_head *cmpl_list)
 844 {
 845         struct mei_device *dev = cl->dev;
 846         u32 msg_slots;
 847         int slots;
 848         int ret;
 849
 850         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 851         slots = mei_hbuf_empty_slots(dev);
 852
 853         if (slots < msg_slots)
 854                 return -EMSGSIZE;
 855
 856         ret = mei_cl_send_disconnect(cl, cb);
 857         if (ret)
 858                 list_move_tail(&cb->list, cmpl_list);
 859
 860         return ret;
 861 }
 862
 863 /**
 864  * __mei_cl_disconnect - disconnect host client from the me one
 865  *     internal function runtime pm has to be already acquired
 866  *
 867  * @cl: host client
 868  *
 869  * Return: 0 on success, <0 on failure.
 870  */
 871 static int __mei_cl_disconnect(struct mei_cl *cl)
 872 {
 873         struct mei_device *dev;
 874         struct mei_cl_cb *cb;
 875         int rets;
 876
 877         dev = cl->dev;
 878
 879         cl->state = MEI_FILE_DISCONNECTING;
 880
 881         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT, NULL);
 882         if (!cb) {
 883                 rets = -ENOMEM;
 884                 goto out;
 885         }
 886
 887         if (mei_hbuf_acquire(dev)) {
 888                 rets = mei_cl_send_disconnect(cl, cb);
 889                 if (rets) {
 890                         cl_err(dev, cl, "failed to disconnect.\n");
 891                         goto out;
 892                 }
 893         }
 894
 895         mutex_unlock(&dev->device_lock);
 896         wait_event_timeout(cl->wait,
 897                            cl->state == MEI_FILE_DISCONNECT_REPLY ||
 898                            cl->state == MEI_FILE_DISCONNECTED,
 899                            mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 900         mutex_lock(&dev->device_lock);
 901
 902         rets = cl->status;
 903         if (cl->state != MEI_FILE_DISCONNECT_REPLY &&
 904             cl->state != MEI_FILE_DISCONNECTED) {
 905                 cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
 906                 rets = -ETIME;
 907         }
 908
 909 out:
 910         /* we disconnect also on error */
 911         mei_cl_set_disconnected(cl);
 912         if (!rets)
 913                 cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
 914
 915         mei_io_cb_free(cb);
 916         return rets;
 917 }
 918
 919 /**
 920  * mei_cl_disconnect - disconnect host client from the me one
 921  *
 922  * @cl: host client
 923  *
 924  * Locking: called under "dev->device_lock" lock
 925  *
 926  * Return: 0 on success, <0 on failure.
 927  */
 928 int mei_cl_disconnect(struct mei_cl *cl)
 929 {
 930         struct mei_device *dev;
 931         int rets;
 932
 933         if (WARN_ON(!cl || !cl->dev))
 934                 return -ENODEV;
 935
 936         dev = cl->dev;
 937
 938         cl_dbg(dev, cl, "disconnecting");
 939
 940         if (!mei_cl_is_connected(cl))
 941                 return 0;
 942
 943         if (mei_cl_is_fixed_address(cl)) {
 944                 mei_cl_set_disconnected(cl);
 945                 return 0;
 946         }
 947
 948         rets = pm_runtime_get(dev->dev);
 949         if (rets < 0 && rets != -EINPROGRESS) {
 950                 pm_runtime_put_noidle(dev->dev);
 951                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
 952                 return rets;
 953         }
 954
 955         rets = __mei_cl_disconnect(cl);
 956
 957         cl_dbg(dev, cl, "rpm: autosuspend\n");
 958         pm_runtime_mark_last_busy(dev->dev);
 959         pm_runtime_put_autosuspend(dev->dev);
 960
 961         return rets;
 962 }
 963
 964
 965 /**
 966  * mei_cl_is_other_connecting - checks if other
 967  *    client with the same me client id is connecting
 968  *
 969  * @cl: private data of the file object
 970  *
 971  * Return: true if other client is connected, false - otherwise.
 972  */
 973 static bool mei_cl_is_other_connecting(struct mei_cl *cl)
 974 {
 975         struct mei_device *dev;
 976         struct mei_cl_cb *cb;
 977
 978         dev = cl->dev;
 979
 980         list_for_each_entry(cb, &dev->ctrl_rd_list, list) {
 981                 if (cb->fop_type == MEI_FOP_CONNECT &&
 982                     mei_cl_me_id(cl) == mei_cl_me_id(cb->cl))
 983                         return true;
 984         }
 985
 986         return false;
 987 }
 988
 989 /**
 990  * mei_cl_send_connect - send connect request
 991  *
 992  * @cl: host client
 993  * @cb: callback block
 994  *
 995  * Return: 0, OK; otherwise, error.
 996  */
 997 static int mei_cl_send_connect(struct mei_cl *cl, struct mei_cl_cb *cb)
 998 {
 999         struct mei_device *dev;
1000         int ret;
1001
1002         dev = cl->dev;
1003
1004         ret = mei_hbm_cl_connect_req(dev, cl);
1005         cl->status = ret;
1006         if (ret) {
1007                 cl->state = MEI_FILE_DISCONNECT_REPLY;
1008                 return ret;
1009         }
1010
1011         list_move_tail(&cb->list, &dev->ctrl_rd_list);
1012         cl->timer_count = MEI_CONNECT_TIMEOUT;
1013         mei_schedule_stall_timer(dev);
1014         return 0;
1015 }
1016
1017 /**
1018  * mei_cl_irq_connect - send connect request in irq_thread context
1019  *
1020  * @cl: host client
1021  * @cb: callback block
1022  * @cmpl_list: complete list
1023  *
1024  * Return: 0, OK; otherwise, error.
1025  */
1026 int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
1027                        struct list_head *cmpl_list)
1028 {
1029         struct mei_device *dev = cl->dev;
1030         u32 msg_slots;
1031         int slots;
1032         int rets;
1033
1034         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1035         slots = mei_hbuf_empty_slots(dev);
1036
1037         if (mei_cl_is_other_connecting(cl))
1038                 return 0;
1039
1040         if (slots < msg_slots)
1041                 return -EMSGSIZE;
1042
1043         rets = mei_cl_send_connect(cl, cb);
1044         if (rets)
1045                 list_move_tail(&cb->list, cmpl_list);
1046
1047         return rets;
1048 }
1049
1050 /**
1051  * mei_cl_connect - connect host client to the me one
1052  *
1053  * @cl: host client
1054  * @me_cl: me client
1055  * @fp: pointer to file structure
1056  *
1057  * Locking: called under "dev->device_lock" lock
1058  *
1059  * Return: 0 on success, <0 on failure.
1060  */
1061 int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
1062                    const struct file *fp)
1063 {
1064         struct mei_device *dev;
1065         struct mei_cl_cb *cb;
1066         int rets;
1067
1068         if (WARN_ON(!cl || !cl->dev || !me_cl))
1069                 return -ENODEV;
1070
1071         dev = cl->dev;
1072
1073         if (!mei_cl_bus_module_get(cl))
1074                 return -ENODEV;
1075
1076         rets = mei_cl_set_connecting(cl, me_cl);
1077         if (rets)
1078                 goto nortpm;
1079
1080         if (mei_cl_is_fixed_address(cl)) {
1081                 cl->state = MEI_FILE_CONNECTED;
1082                 rets = 0;
1083                 goto nortpm;
1084         }
1085
1086         rets = pm_runtime_get(dev->dev);
1087         if (rets < 0 && rets != -EINPROGRESS) {
1088                 pm_runtime_put_noidle(dev->dev);
1089                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1090                 goto nortpm;
1091         }
1092
1093         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_CONNECT, fp);
1094         if (!cb) {
1095                 rets = -ENOMEM;
1096                 goto out;
1097         }
1098
1099         /* run hbuf acquire last so we don't have to undo */
1100         if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
1101                 rets = mei_cl_send_connect(cl, cb);
1102                 if (rets)
1103                         goto out;
1104         }
1105
1106         mutex_unlock(&dev->device_lock);
1107         wait_event_timeout(cl->wait,
1108                         (cl->state == MEI_FILE_CONNECTED ||
1109                          cl->state == MEI_FILE_DISCONNECTED ||
1110                          cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
1111                          cl->state == MEI_FILE_DISCONNECT_REPLY),
1112                         mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1113         mutex_lock(&dev->device_lock);
1114
1115         if (!mei_cl_is_connected(cl)) {
1116                 if (cl->state == MEI_FILE_DISCONNECT_REQUIRED) {
1117                         mei_io_list_flush_cl(&dev->ctrl_rd_list, cl);
1118                         mei_io_list_flush_cl(&dev->ctrl_wr_list, cl);
1119                          /* ignore disconnect return valuue;
1120                           * in case of failure reset will be invoked
1121                           */
1122                         __mei_cl_disconnect(cl);
1123                         rets = -EFAULT;
1124                         goto out;
1125                 }
1126
1127                 /* timeout or something went really wrong */
1128                 if (!cl->status)
1129                         cl->status = -EFAULT;
1130         }
1131
1132         rets = cl->status;
1133 out:
1134         cl_dbg(dev, cl, "rpm: autosuspend\n");
1135         pm_runtime_mark_last_busy(dev->dev);
1136         pm_runtime_put_autosuspend(dev->dev);
1137
1138         mei_io_cb_free(cb);
1139
1140 nortpm:
1141         if (!mei_cl_is_connected(cl))
1142                 mei_cl_set_disconnected(cl);
1143
1144         return rets;
1145 }
1146
1147 /**
1148  * mei_cl_alloc_linked - allocate and link host client
1149  *
1150  * @dev: the device structure
1151  *
1152  * Return: cl on success ERR_PTR on failure
1153  */
1154 struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev)
1155 {
1156         struct mei_cl *cl;
1157         int ret;
1158
1159         cl = mei_cl_allocate(dev);
1160         if (!cl) {
1161                 ret = -ENOMEM;
1162                 goto err;
1163         }
1164
1165         ret = mei_cl_link(cl);
1166         if (ret)
1167                 goto err;
1168
1169         return cl;
1170 err:
1171         kfree(cl);
1172         return ERR_PTR(ret);
1173 }
1174
1175 /**
1176  * mei_cl_tx_flow_ctrl_creds - checks flow_control credits for cl.
1177  *
1178  * @cl: host client
1179  *
1180  * Return: 1 if tx_flow_ctrl_creds >0, 0 - otherwise.
1181  */
1182 static int mei_cl_tx_flow_ctrl_creds(struct mei_cl *cl)
1183 {
1184         if (WARN_ON(!cl || !cl->me_cl))
1185                 return -EINVAL;
1186
1187         if (cl->tx_flow_ctrl_creds > 0)
1188                 return 1;
1189
1190         if (mei_cl_is_fixed_address(cl))
1191                 return 1;
1192
1193         if (mei_cl_is_single_recv_buf(cl)) {
1194                 if (cl->me_cl->tx_flow_ctrl_creds > 0)
1195                         return 1;
1196         }
1197         return 0;
1198 }
1199
1200 /**
1201  * mei_cl_tx_flow_ctrl_creds_reduce - reduces transmit flow control credits
1202  *   for a client
1203  *
1204  * @cl: host client
1205  *
1206  * Return:
1207  *      0 on success
1208  *      -EINVAL when ctrl credits are <= 0
1209  */
1210 static int mei_cl_tx_flow_ctrl_creds_reduce(struct mei_cl *cl)
1211 {
1212         if (WARN_ON(!cl || !cl->me_cl))
1213                 return -EINVAL;
1214
1215         if (mei_cl_is_fixed_address(cl))
1216                 return 0;
1217
1218         if (mei_cl_is_single_recv_buf(cl)) {
1219                 if (WARN_ON(cl->me_cl->tx_flow_ctrl_creds <= 0))
1220                         return -EINVAL;
1221                 cl->me_cl->tx_flow_ctrl_creds--;
1222         } else {
1223                 if (WARN_ON(cl->tx_flow_ctrl_creds <= 0))
1224                         return -EINVAL;
1225                 cl->tx_flow_ctrl_creds--;
1226         }
1227         return 0;
1228 }
1229
1230 /**
1231  *  mei_cl_notify_fop2req - convert fop to proper request
1232  *
1233  * @fop: client notification start response command
1234  *
1235  * Return:  MEI_HBM_NOTIFICATION_START/STOP
1236  */
1237 u8 mei_cl_notify_fop2req(enum mei_cb_file_ops fop)
1238 {
1239         if (fop == MEI_FOP_NOTIFY_START)
1240                 return MEI_HBM_NOTIFICATION_START;
1241         else
1242                 return MEI_HBM_NOTIFICATION_STOP;
1243 }
1244
1245 /**
1246  *  mei_cl_notify_req2fop - convert notification request top file operation type
1247  *
1248  * @req: hbm notification request type
1249  *
1250  * Return:  MEI_FOP_NOTIFY_START/STOP
1251  */
1252 enum mei_cb_file_ops mei_cl_notify_req2fop(u8 req)
1253 {
1254         if (req == MEI_HBM_NOTIFICATION_START)
1255                 return MEI_FOP_NOTIFY_START;
1256         else
1257                 return MEI_FOP_NOTIFY_STOP;
1258 }
1259
1260 /**
1261  * mei_cl_irq_notify - send notification request in irq_thread context
1262  *
1263  * @cl: client
1264  * @cb: callback block.
1265  * @cmpl_list: complete list.
1266  *
1267  * Return: 0 on such and error otherwise.
1268  */
1269 int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
1270                       struct list_head *cmpl_list)
1271 {
1272         struct mei_device *dev = cl->dev;
1273         u32 msg_slots;
1274         int slots;
1275         int ret;
1276         bool request;
1277
1278         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1279         slots = mei_hbuf_empty_slots(dev);
1280
1281         if (slots < msg_slots)
1282                 return -EMSGSIZE;
1283
1284         request = mei_cl_notify_fop2req(cb->fop_type);
1285         ret = mei_hbm_cl_notify_req(dev, cl, request);
1286         if (ret) {
1287                 cl->status = ret;
1288                 list_move_tail(&cb->list, cmpl_list);
1289                 return ret;
1290         }
1291
1292         list_move_tail(&cb->list, &dev->ctrl_rd_list);
1293         return 0;
1294 }
1295
1296 /**
1297  * mei_cl_notify_request - send notification stop/start request
1298  *
1299  * @cl: host client
1300  * @fp: associate request with file
1301  * @request: 1 for start or 0 for stop
1302  *
1303  * Locking: called under "dev->device_lock" lock
1304  *
1305  * Return: 0 on such and error otherwise.
1306  */
1307 int mei_cl_notify_request(struct mei_cl *cl,
1308                           const struct file *fp, u8 request)
1309 {
1310         struct mei_device *dev;
1311         struct mei_cl_cb *cb;
1312         enum mei_cb_file_ops fop_type;
1313         int rets;
1314
1315         if (WARN_ON(!cl || !cl->dev))
1316                 return -ENODEV;
1317
1318         dev = cl->dev;
1319
1320         if (!dev->hbm_f_ev_supported) {
1321                 cl_dbg(dev, cl, "notifications not supported\n");
1322                 return -EOPNOTSUPP;
1323         }
1324
1325         if (!mei_cl_is_connected(cl))
1326                 return -ENODEV;
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);
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 (!dev->hbm_f_ev_supported) {
1423                 cl_dbg(dev, cl, "notifications not supported\n");
1424                 return -EOPNOTSUPP;
1425         }
1426
1427         if (!mei_cl_is_connected(cl))
1428                 return -ENODEV;
1429
1430         if (cl->notify_ev)
1431                 goto out;
1432
1433         if (!block)
1434                 return -EAGAIN;
1435
1436         mutex_unlock(&dev->device_lock);
1437         rets = wait_event_interruptible(cl->ev_wait, cl->notify_ev);
1438         mutex_lock(&dev->device_lock);
1439
1440         if (rets < 0)
1441                 return rets;
1442
1443 out:
1444         *notify_ev = cl->notify_ev;
1445         cl->notify_ev = false;
1446         return 0;
1447 }
1448
1449 /**
1450  * mei_cl_read_start - the start read client message function.
1451  *
1452  * @cl: host client
1453  * @length: number of bytes to read
1454  * @fp: pointer to file structure
1455  *
1456  * Return: 0 on success, <0 on failure.
1457  */
1458 int mei_cl_read_start(struct mei_cl *cl, size_t length, const struct file *fp)
1459 {
1460         struct mei_device *dev;
1461         struct mei_cl_cb *cb;
1462         int rets;
1463
1464         if (WARN_ON(!cl || !cl->dev))
1465                 return -ENODEV;
1466
1467         dev = cl->dev;
1468
1469         if (!mei_cl_is_connected(cl))
1470                 return -ENODEV;
1471
1472         if (!mei_me_cl_is_active(cl->me_cl)) {
1473                 cl_err(dev, cl, "no such me client\n");
1474                 return  -ENOTTY;
1475         }
1476
1477         if (mei_cl_is_fixed_address(cl))
1478                 return 0;
1479
1480         /* HW currently supports only one pending read */
1481         if (cl->rx_flow_ctrl_creds)
1482                 return -EBUSY;
1483
1484         cb = mei_cl_enqueue_ctrl_wr_cb(cl, length, MEI_FOP_READ, fp);
1485         if (!cb)
1486                 return -ENOMEM;
1487
1488         rets = pm_runtime_get(dev->dev);
1489         if (rets < 0 && rets != -EINPROGRESS) {
1490                 pm_runtime_put_noidle(dev->dev);
1491                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1492                 goto nortpm;
1493         }
1494
1495         rets = 0;
1496         if (mei_hbuf_acquire(dev)) {
1497                 rets = mei_hbm_cl_flow_control_req(dev, cl);
1498                 if (rets < 0)
1499                         goto out;
1500
1501                 list_move_tail(&cb->list, &cl->rd_pending);
1502         }
1503         cl->rx_flow_ctrl_creds++;
1504
1505 out:
1506         cl_dbg(dev, cl, "rpm: autosuspend\n");
1507         pm_runtime_mark_last_busy(dev->dev);
1508         pm_runtime_put_autosuspend(dev->dev);
1509 nortpm:
1510         if (rets)
1511                 mei_io_cb_free(cb);
1512
1513         return rets;
1514 }
1515
1516 /**
1517  * mei_cl_irq_write - write a message to device
1518  *      from the interrupt thread context
1519  *
1520  * @cl: client
1521  * @cb: callback block.
1522  * @cmpl_list: complete list.
1523  *
1524  * Return: 0, OK; otherwise error.
1525  */
1526 int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
1527                      struct list_head *cmpl_list)
1528 {
1529         struct mei_device *dev;
1530         struct mei_msg_data *buf;
1531         struct mei_msg_hdr mei_hdr;
1532         size_t len;
1533         u32 msg_slots;
1534         int slots;
1535         int rets;
1536         bool first_chunk;
1537
1538         if (WARN_ON(!cl || !cl->dev))
1539                 return -ENODEV;
1540
1541         dev = cl->dev;
1542
1543         buf = &cb->buf;
1544
1545         first_chunk = cb->buf_idx == 0;
1546
1547         rets = first_chunk ? mei_cl_tx_flow_ctrl_creds(cl) : 1;
1548         if (rets < 0)
1549                 goto err;
1550
1551         if (rets == 0) {
1552                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1553                 return 0;
1554         }
1555
1556         slots = mei_hbuf_empty_slots(dev);
1557         len = buf->size - cb->buf_idx;
1558         msg_slots = mei_data2slots(len);
1559
1560         mei_hdr.host_addr = mei_cl_host_addr(cl);
1561         mei_hdr.me_addr = mei_cl_me_id(cl);
1562         mei_hdr.reserved = 0;
1563         mei_hdr.internal = cb->internal;
1564
1565         if (slots >= msg_slots) {
1566                 mei_hdr.length = len;
1567                 mei_hdr.msg_complete = 1;
1568         /* Split the message only if we can write the whole host buffer */
1569         } else if (slots == dev->hbuf_depth) {
1570                 msg_slots = slots;
1571                 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
1572                 mei_hdr.length = len;
1573                 mei_hdr.msg_complete = 0;
1574         } else {
1575                 /* wait for next time the host buffer is empty */
1576                 return 0;
1577         }
1578
1579         cl_dbg(dev, cl, "buf: size = %zu idx = %zu\n",
1580                         cb->buf.size, cb->buf_idx);
1581
1582         rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
1583         if (rets)
1584                 goto err;
1585
1586         cl->status = 0;
1587         cl->writing_state = MEI_WRITING;
1588         cb->buf_idx += mei_hdr.length;
1589         cb->completed = mei_hdr.msg_complete == 1;
1590
1591         if (first_chunk) {
1592                 if (mei_cl_tx_flow_ctrl_creds_reduce(cl)) {
1593                         rets = -EIO;
1594                         goto err;
1595                 }
1596         }
1597
1598         if (mei_hdr.msg_complete)
1599                 list_move_tail(&cb->list, &dev->write_waiting_list);
1600
1601         return 0;
1602
1603 err:
1604         cl->status = rets;
1605         list_move_tail(&cb->list, cmpl_list);
1606         return rets;
1607 }
1608
1609 /**
1610  * mei_cl_write - submit a write cb to mei device
1611  *      assumes device_lock is locked
1612  *
1613  * @cl: host client
1614  * @cb: write callback with filled data
1615  *
1616  * Return: number of bytes sent on success, <0 on failure.
1617  */
1618 int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb)
1619 {
1620         struct mei_device *dev;
1621         struct mei_msg_data *buf;
1622         struct mei_msg_hdr mei_hdr;
1623         int size;
1624         int rets;
1625         bool blocking;
1626
1627         if (WARN_ON(!cl || !cl->dev))
1628                 return -ENODEV;
1629
1630         if (WARN_ON(!cb))
1631                 return -EINVAL;
1632
1633         dev = cl->dev;
1634
1635         buf = &cb->buf;
1636         size = buf->size;
1637         blocking = cb->blocking;
1638
1639         cl_dbg(dev, cl, "size=%d\n", size);
1640
1641         rets = pm_runtime_get(dev->dev);
1642         if (rets < 0 && rets != -EINPROGRESS) {
1643                 pm_runtime_put_noidle(dev->dev);
1644                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1645                 goto free;
1646         }
1647
1648         cb->buf_idx = 0;
1649         cl->writing_state = MEI_IDLE;
1650
1651         mei_hdr.host_addr = mei_cl_host_addr(cl);
1652         mei_hdr.me_addr = mei_cl_me_id(cl);
1653         mei_hdr.reserved = 0;
1654         mei_hdr.msg_complete = 0;
1655         mei_hdr.internal = cb->internal;
1656
1657         rets = mei_cl_tx_flow_ctrl_creds(cl);
1658         if (rets < 0)
1659                 goto err;
1660
1661         if (rets == 0) {
1662                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1663                 rets = size;
1664                 goto out;
1665         }
1666         if (!mei_hbuf_acquire(dev)) {
1667                 cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
1668                 rets = size;
1669                 goto out;
1670         }
1671
1672         /* Check for a maximum length */
1673         if (size > mei_hbuf_max_len(dev)) {
1674                 mei_hdr.length = mei_hbuf_max_len(dev);
1675                 mei_hdr.msg_complete = 0;
1676         } else {
1677                 mei_hdr.length = size;
1678                 mei_hdr.msg_complete = 1;
1679         }
1680
1681         rets = mei_write_message(dev, &mei_hdr, buf->data);
1682         if (rets)
1683                 goto err;
1684
1685         rets = mei_cl_tx_flow_ctrl_creds_reduce(cl);
1686         if (rets)
1687                 goto err;
1688
1689         cl->writing_state = MEI_WRITING;
1690         cb->buf_idx = mei_hdr.length;
1691         cb->completed = mei_hdr.msg_complete == 1;
1692
1693 out:
1694         if (mei_hdr.msg_complete)
1695                 list_add_tail(&cb->list, &dev->write_waiting_list);
1696         else
1697                 list_add_tail(&cb->list, &dev->write_list);
1698
1699         cb = NULL;
1700         if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
1701
1702                 mutex_unlock(&dev->device_lock);
1703                 rets = wait_event_interruptible(cl->tx_wait,
1704                                 cl->writing_state == MEI_WRITE_COMPLETE ||
1705                                 (!mei_cl_is_connected(cl)));
1706                 mutex_lock(&dev->device_lock);
1707                 /* wait_event_interruptible returns -ERESTARTSYS */
1708                 if (rets) {
1709                         if (signal_pending(current))
1710                                 rets = -EINTR;
1711                         goto err;
1712                 }
1713                 if (cl->writing_state != MEI_WRITE_COMPLETE) {
1714                         rets = -EFAULT;
1715                         goto err;
1716                 }
1717         }
1718
1719         rets = size;
1720 err:
1721         cl_dbg(dev, cl, "rpm: autosuspend\n");
1722         pm_runtime_mark_last_busy(dev->dev);
1723         pm_runtime_put_autosuspend(dev->dev);
1724 free:
1725         mei_io_cb_free(cb);
1726
1727         return rets;
1728 }
1729
1730
1731 /**
1732  * mei_cl_complete - processes completed operation for a client
1733  *
1734  * @cl: private data of the file object.
1735  * @cb: callback block.
1736  */
1737 void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
1738 {
1739         struct mei_device *dev = cl->dev;
1740
1741         switch (cb->fop_type) {
1742         case MEI_FOP_WRITE:
1743                 mei_io_cb_free(cb);
1744                 cl->writing_state = MEI_WRITE_COMPLETE;
1745                 if (waitqueue_active(&cl->tx_wait)) {
1746                         wake_up_interruptible(&cl->tx_wait);
1747                 } else {
1748                         pm_runtime_mark_last_busy(dev->dev);
1749                         pm_request_autosuspend(dev->dev);
1750                 }
1751                 break;
1752
1753         case MEI_FOP_READ:
1754                 list_add_tail(&cb->list, &cl->rd_completed);
1755                 if (!mei_cl_is_fixed_address(cl) &&
1756                     !WARN_ON(!cl->rx_flow_ctrl_creds))
1757                         cl->rx_flow_ctrl_creds--;
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         case MEI_FOP_DISCONNECT_RSP:
1771                 mei_io_cb_free(cb);
1772                 mei_cl_set_disconnected(cl);
1773                 break;
1774         default:
1775                 BUG_ON(0);
1776         }
1777 }
1778
1779
1780 /**
1781  * mei_cl_all_disconnect - disconnect forcefully all connected clients
1782  *
1783  * @dev: mei device
1784  */
1785 void mei_cl_all_disconnect(struct mei_device *dev)
1786 {
1787         struct mei_cl *cl;
1788
1789         list_for_each_entry(cl, &dev->file_list, link)
1790                 mei_cl_set_disconnected(cl);
1791 }