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_tx_cb_queue - queue tx callback
 354  *
 355  * Locking: called under "dev->device_lock" lock
 356  *
 357  * @cb: mei callback struct
 358  * @head: an instance of list to queue on
 359  */
 360 static inline void mei_tx_cb_enqueue(struct mei_cl_cb *cb,
 361                                      struct list_head *head)
 362 {
 363         list_add_tail(&cb->list, head);
 364         cb->cl->tx_cb_queued++;
 365 }
 366
 367 /**
 368  * mei_tx_cb_dequeue - dequeue tx callback
 369  *
 370  * Locking: called under "dev->device_lock" lock
 371  *
 372  * @cb: mei callback struct to dequeue and free
 373  */
 374 static inline void mei_tx_cb_dequeue(struct mei_cl_cb *cb)
 375 {
 376         if (!WARN_ON(cb->cl->tx_cb_queued == 0))
 377                 cb->cl->tx_cb_queued--;
 378
 379         mei_io_cb_free(cb);
 380 }
 381
 382 /**
 383  * mei_io_cb_init - allocate and initialize io callback
 384  *
 385  * @cl: mei client
 386  * @type: operation type
 387  * @fp: pointer to file structure
 388  *
 389  * Return: mei_cl_cb pointer or NULL;
 390  */
 391 static struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl,
 392                                         enum mei_cb_file_ops type,
 393                                         const struct file *fp)
 394 {
 395         struct mei_cl_cb *cb;
 396
 397         cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
 398         if (!cb)
 399                 return NULL;
 400
 401         INIT_LIST_HEAD(&cb->list);
 402         cb->fp = fp;
 403         cb->cl = cl;
 404         cb->buf_idx = 0;
 405         cb->fop_type = type;
 406         return cb;
 407 }
 408
 409 /**
 410  * mei_io_list_flush_cl - removes cbs belonging to the cl.
 411  *
 412  * @head:  an instance of our list structure
 413  * @cl:    host client
 414  */
 415 static void mei_io_list_flush_cl(struct list_head *head,
 416                                  const struct mei_cl *cl)
 417 {
 418         struct mei_cl_cb *cb, *next;
 419
 420         list_for_each_entry_safe(cb, next, head, list) {
 421                 if (mei_cl_cmp_id(cl, cb->cl))
 422                         list_del_init(&cb->list);
 423         }
 424 }
 425
 426 /**
 427  * mei_io_tx_list_free_cl - removes cb belonging to the cl and free them
 428  *
 429  * @head: An instance of our list structure
 430  * @cl: host client
 431  */
 432 static void mei_io_tx_list_free_cl(struct list_head *head,
 433                                    const struct mei_cl *cl)
 434 {
 435         struct mei_cl_cb *cb, *next;
 436
 437         list_for_each_entry_safe(cb, next, head, list) {
 438                 if (mei_cl_cmp_id(cl, cb->cl))
 439                         mei_tx_cb_dequeue(cb);
 440         }
 441 }
 442
 443 /**
 444  * mei_io_list_free_fp - free cb from a list that matches file pointer
 445  *
 446  * @head: io list
 447  * @fp: file pointer (matching cb file object), may be NULL
 448  */
 449 static void mei_io_list_free_fp(struct list_head *head, const struct file *fp)
 450 {
 451         struct mei_cl_cb *cb, *next;
 452
 453         list_for_each_entry_safe(cb, next, head, list)
 454                 if (!fp || fp == cb->fp)
 455                         mei_io_cb_free(cb);
 456 }
 457
 458 /**
 459  * mei_cl_alloc_cb - a convenient wrapper for allocating read cb
 460  *
 461  * @cl: host client
 462  * @length: size of the buffer
 463  * @fop_type: operation type
 464  * @fp: associated file pointer (might be NULL)
 465  *
 466  * Return: cb on success and NULL on failure
 467  */
 468 struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
 469                                   enum mei_cb_file_ops fop_type,
 470                                   const struct file *fp)
 471 {
 472         struct mei_cl_cb *cb;
 473
 474         cb = mei_io_cb_init(cl, fop_type, fp);
 475         if (!cb)
 476                 return NULL;
 477
 478         if (length == 0)
 479                 return cb;
 480
 481         cb->buf.data = kmalloc(length, GFP_KERNEL);
 482         if (!cb->buf.data) {
 483                 mei_io_cb_free(cb);
 484                 return NULL;
 485         }
 486         cb->buf.size = length;
 487
 488         return cb;
 489 }
 490
 491 /**
 492  * mei_cl_enqueue_ctrl_wr_cb - a convenient wrapper for allocating
 493  *     and enqueuing of the control commands cb
 494  *
 495  * @cl: host client
 496  * @length: size of the buffer
 497  * @fop_type: operation type
 498  * @fp: associated file pointer (might be NULL)
 499  *
 500  * Return: cb on success and NULL on failure
 501  * Locking: called under "dev->device_lock" lock
 502  */
 503 struct mei_cl_cb *mei_cl_enqueue_ctrl_wr_cb(struct mei_cl *cl, size_t length,
 504                                             enum mei_cb_file_ops fop_type,
 505                                             const struct file *fp)
 506 {
 507         struct mei_cl_cb *cb;
 508
 509         /* for RX always allocate at least client's mtu */
 510         if (length)
 511                 length = max_t(size_t, length, mei_cl_mtu(cl));
 512
 513         cb = mei_cl_alloc_cb(cl, length, fop_type, fp);
 514         if (!cb)
 515                 return NULL;
 516
 517         list_add_tail(&cb->list, &cl->dev->ctrl_wr_list);
 518         return cb;
 519 }
 520
 521 /**
 522  * mei_cl_read_cb - find this cl's callback in the read list
 523  *     for a specific file
 524  *
 525  * @cl: host client
 526  * @fp: file pointer (matching cb file object), may be NULL
 527  *
 528  * Return: cb on success, NULL if cb is not found
 529  */
 530 struct mei_cl_cb *mei_cl_read_cb(const struct mei_cl *cl, const struct file *fp)
 531 {
 532         struct mei_cl_cb *cb;
 533
 534         list_for_each_entry(cb, &cl->rd_completed, list)
 535                 if (!fp || fp == cb->fp)
 536                         return cb;
 537
 538         return NULL;
 539 }
 540
 541 /**
 542  * mei_cl_flush_queues - flushes queue lists belonging to cl.
 543  *
 544  * @cl: host client
 545  * @fp: file pointer (matching cb file object), may be NULL
 546  *
 547  * Return: 0 on success, -EINVAL if cl or cl->dev is NULL.
 548  */
 549 int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp)
 550 {
 551         struct mei_device *dev;
 552
 553         if (WARN_ON(!cl || !cl->dev))
 554                 return -EINVAL;
 555
 556         dev = cl->dev;
 557
 558         cl_dbg(dev, cl, "remove list entry belonging to cl\n");
 559         mei_io_tx_list_free_cl(&cl->dev->write_list, cl);
 560         mei_io_tx_list_free_cl(&cl->dev->write_waiting_list, cl);
 561         mei_io_list_flush_cl(&cl->dev->ctrl_wr_list, cl);
 562         mei_io_list_flush_cl(&cl->dev->ctrl_rd_list, cl);
 563         mei_io_list_free_fp(&cl->rd_pending, fp);
 564         mei_io_list_free_fp(&cl->rd_completed, fp);
 565
 566         return 0;
 567 }
 568
 569 /**
 570  * mei_cl_init - initializes cl.
 571  *
 572  * @cl: host client to be initialized
 573  * @dev: mei device
 574  */
 575 static void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
 576 {
 577         memset(cl, 0, sizeof(struct mei_cl));
 578         init_waitqueue_head(&cl->wait);
 579         init_waitqueue_head(&cl->rx_wait);
 580         init_waitqueue_head(&cl->tx_wait);
 581         init_waitqueue_head(&cl->ev_wait);
 582         INIT_LIST_HEAD(&cl->rd_completed);
 583         INIT_LIST_HEAD(&cl->rd_pending);
 584         INIT_LIST_HEAD(&cl->link);
 585         cl->writing_state = MEI_IDLE;
 586         cl->state = MEI_FILE_UNINITIALIZED;
 587         cl->dev = dev;
 588 }
 589
 590 /**
 591  * mei_cl_allocate - allocates cl  structure and sets it up.
 592  *
 593  * @dev: mei device
 594  * Return:  The allocated file or NULL on failure
 595  */
 596 struct mei_cl *mei_cl_allocate(struct mei_device *dev)
 597 {
 598         struct mei_cl *cl;
 599
 600         cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
 601         if (!cl)
 602                 return NULL;
 603
 604         mei_cl_init(cl, dev);
 605
 606         return cl;
 607 }
 608
 609 /**
 610  * mei_cl_link - allocate host id in the host map
 611  *
 612  * @cl: host client
 613  *
 614  * Return: 0 on success
 615  *      -EINVAL on incorrect values
 616  *      -EMFILE if open count exceeded.
 617  */
 618 int mei_cl_link(struct mei_cl *cl)
 619 {
 620         struct mei_device *dev;
 621         int id;
 622
 623         if (WARN_ON(!cl || !cl->dev))
 624                 return -EINVAL;
 625
 626         dev = cl->dev;
 627
 628         id = find_first_zero_bit(dev->host_clients_map, MEI_CLIENTS_MAX);
 629         if (id >= MEI_CLIENTS_MAX) {
 630                 dev_err(dev->dev, "id exceeded %d", MEI_CLIENTS_MAX);
 631                 return -EMFILE;
 632         }
 633
 634         if (dev->open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
 635                 dev_err(dev->dev, "open_handle_count exceeded %d",
 636                         MEI_MAX_OPEN_HANDLE_COUNT);
 637                 return -EMFILE;
 638         }
 639
 640         dev->open_handle_count++;
 641
 642         cl->host_client_id = id;
 643         list_add_tail(&cl->link, &dev->file_list);
 644
 645         set_bit(id, dev->host_clients_map);
 646
 647         cl->state = MEI_FILE_INITIALIZING;
 648
 649         cl_dbg(dev, cl, "link cl\n");
 650         return 0;
 651 }
 652
 653 /**
 654  * mei_cl_unlink - remove host client from the list
 655  *
 656  * @cl: host client
 657  *
 658  * Return: always 0
 659  */
 660 int mei_cl_unlink(struct mei_cl *cl)
 661 {
 662         struct mei_device *dev;
 663
 664         /* don't shout on error exit path */
 665         if (!cl)
 666                 return 0;
 667
 668         if (WARN_ON(!cl->dev))
 669                 return 0;
 670
 671         dev = cl->dev;
 672
 673         cl_dbg(dev, cl, "unlink client");
 674
 675         if (dev->open_handle_count > 0)
 676                 dev->open_handle_count--;
 677
 678         /* never clear the 0 bit */
 679         if (cl->host_client_id)
 680                 clear_bit(cl->host_client_id, dev->host_clients_map);
 681
 682         list_del_init(&cl->link);
 683
 684         cl->state = MEI_FILE_UNINITIALIZED;
 685         cl->writing_state = MEI_IDLE;
 686
 687         WARN_ON(!list_empty(&cl->rd_completed) ||
 688                 !list_empty(&cl->rd_pending) ||
 689                 !list_empty(&cl->link));
 690
 691         return 0;
 692 }
 693
 694 void mei_host_client_init(struct mei_device *dev)
 695 {
 696         dev->dev_state = MEI_DEV_ENABLED;
 697         dev->reset_count = 0;
 698
 699         schedule_work(&dev->bus_rescan_work);
 700
 701         pm_runtime_mark_last_busy(dev->dev);
 702         dev_dbg(dev->dev, "rpm: autosuspend\n");
 703         pm_request_autosuspend(dev->dev);
 704 }
 705
 706 /**
 707  * mei_hbuf_acquire - try to acquire host buffer
 708  *
 709  * @dev: the device structure
 710  * Return: true if host buffer was acquired
 711  */
 712 bool mei_hbuf_acquire(struct mei_device *dev)
 713 {
 714         if (mei_pg_state(dev) == MEI_PG_ON ||
 715             mei_pg_in_transition(dev)) {
 716                 dev_dbg(dev->dev, "device is in pg\n");
 717                 return false;
 718         }
 719
 720         if (!dev->hbuf_is_ready) {
 721                 dev_dbg(dev->dev, "hbuf is not ready\n");
 722                 return false;
 723         }
 724
 725         dev->hbuf_is_ready = false;
 726
 727         return true;
 728 }
 729
 730 /**
 731  * mei_cl_wake_all - wake up readers, writers and event waiters so
 732  *                 they can be interrupted
 733  *
 734  * @cl: host client
 735  */
 736 static void mei_cl_wake_all(struct mei_cl *cl)
 737 {
 738         struct mei_device *dev = cl->dev;
 739
 740         /* synchronized under device mutex */
 741         if (waitqueue_active(&cl->rx_wait)) {
 742                 cl_dbg(dev, cl, "Waking up reading client!\n");
 743                 wake_up_interruptible(&cl->rx_wait);
 744         }
 745         /* synchronized under device mutex */
 746         if (waitqueue_active(&cl->tx_wait)) {
 747                 cl_dbg(dev, cl, "Waking up writing client!\n");
 748                 wake_up_interruptible(&cl->tx_wait);
 749         }
 750         /* synchronized under device mutex */
 751         if (waitqueue_active(&cl->ev_wait)) {
 752                 cl_dbg(dev, cl, "Waking up waiting for event clients!\n");
 753                 wake_up_interruptible(&cl->ev_wait);
 754         }
 755         /* synchronized under device mutex */
 756         if (waitqueue_active(&cl->wait)) {
 757                 cl_dbg(dev, cl, "Waking up ctrl write clients!\n");
 758                 wake_up(&cl->wait);
 759         }
 760 }
 761
 762 /**
 763  * mei_cl_set_disconnected - set disconnected state and clear
 764  *   associated states and resources
 765  *
 766  * @cl: host client
 767  */
 768 static void mei_cl_set_disconnected(struct mei_cl *cl)
 769 {
 770         struct mei_device *dev = cl->dev;
 771
 772         if (cl->state == MEI_FILE_DISCONNECTED ||
 773             cl->state <= MEI_FILE_INITIALIZING)
 774                 return;
 775
 776         cl->state = MEI_FILE_DISCONNECTED;
 777         mei_io_tx_list_free_cl(&dev->write_list, cl);
 778         mei_io_tx_list_free_cl(&dev->write_waiting_list, cl);
 779         mei_io_list_flush_cl(&dev->ctrl_rd_list, cl);
 780         mei_io_list_flush_cl(&dev->ctrl_wr_list, cl);
 781         mei_cl_wake_all(cl);
 782         cl->rx_flow_ctrl_creds = 0;
 783         cl->tx_flow_ctrl_creds = 0;
 784         cl->timer_count = 0;
 785
 786         if (!cl->me_cl)
 787                 return;
 788
 789         if (!WARN_ON(cl->me_cl->connect_count == 0))
 790                 cl->me_cl->connect_count--;
 791
 792         if (cl->me_cl->connect_count == 0)
 793                 cl->me_cl->tx_flow_ctrl_creds = 0;
 794
 795         mei_me_cl_put(cl->me_cl);
 796         cl->me_cl = NULL;
 797 }
 798
 799 static int mei_cl_set_connecting(struct mei_cl *cl, struct mei_me_client *me_cl)
 800 {
 801         if (!mei_me_cl_get(me_cl))
 802                 return -ENOENT;
 803
 804         /* only one connection is allowed for fixed address clients */
 805         if (me_cl->props.fixed_address) {
 806                 if (me_cl->connect_count) {
 807                         mei_me_cl_put(me_cl);
 808                         return -EBUSY;
 809                 }
 810         }
 811
 812         cl->me_cl = me_cl;
 813         cl->state = MEI_FILE_CONNECTING;
 814         cl->me_cl->connect_count++;
 815
 816         return 0;
 817 }
 818
 819 /*
 820  * mei_cl_send_disconnect - send disconnect request
 821  *
 822  * @cl: host client
 823  * @cb: callback block
 824  *
 825  * Return: 0, OK; otherwise, error.
 826  */
 827 static int mei_cl_send_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb)
 828 {
 829         struct mei_device *dev;
 830         int ret;
 831
 832         dev = cl->dev;
 833
 834         ret = mei_hbm_cl_disconnect_req(dev, cl);
 835         cl->status = ret;
 836         if (ret) {
 837                 cl->state = MEI_FILE_DISCONNECT_REPLY;
 838                 return ret;
 839         }
 840
 841         list_move_tail(&cb->list, &dev->ctrl_rd_list);
 842         cl->timer_count = MEI_CONNECT_TIMEOUT;
 843         mei_schedule_stall_timer(dev);
 844
 845         return 0;
 846 }
 847
 848 /**
 849  * mei_cl_irq_disconnect - processes close related operation from
 850  *      interrupt thread context - send disconnect request
 851  *
 852  * @cl: client
 853  * @cb: callback block.
 854  * @cmpl_list: complete list.
 855  *
 856  * Return: 0, OK; otherwise, error.
 857  */
 858 int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
 859                           struct list_head *cmpl_list)
 860 {
 861         struct mei_device *dev = cl->dev;
 862         u32 msg_slots;
 863         int slots;
 864         int ret;
 865
 866         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 867         slots = mei_hbuf_empty_slots(dev);
 868
 869         if (slots < msg_slots)
 870                 return -EMSGSIZE;
 871
 872         ret = mei_cl_send_disconnect(cl, cb);
 873         if (ret)
 874                 list_move_tail(&cb->list, cmpl_list);
 875
 876         return ret;
 877 }
 878
 879 /**
 880  * __mei_cl_disconnect - disconnect host client from the me one
 881  *     internal function runtime pm has to be already acquired
 882  *
 883  * @cl: host client
 884  *
 885  * Return: 0 on success, <0 on failure.
 886  */
 887 static int __mei_cl_disconnect(struct mei_cl *cl)
 888 {
 889         struct mei_device *dev;
 890         struct mei_cl_cb *cb;
 891         int rets;
 892
 893         dev = cl->dev;
 894
 895         cl->state = MEI_FILE_DISCONNECTING;
 896
 897         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT, NULL);
 898         if (!cb) {
 899                 rets = -ENOMEM;
 900                 goto out;
 901         }
 902
 903         if (mei_hbuf_acquire(dev)) {
 904                 rets = mei_cl_send_disconnect(cl, cb);
 905                 if (rets) {
 906                         cl_err(dev, cl, "failed to disconnect.\n");
 907                         goto out;
 908                 }
 909         }
 910
 911         mutex_unlock(&dev->device_lock);
 912         wait_event_timeout(cl->wait,
 913                            cl->state == MEI_FILE_DISCONNECT_REPLY ||
 914                            cl->state == MEI_FILE_DISCONNECTED,
 915                            mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 916         mutex_lock(&dev->device_lock);
 917
 918         rets = cl->status;
 919         if (cl->state != MEI_FILE_DISCONNECT_REPLY &&
 920             cl->state != MEI_FILE_DISCONNECTED) {
 921                 cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
 922                 rets = -ETIME;
 923         }
 924
 925 out:
 926         /* we disconnect also on error */
 927         mei_cl_set_disconnected(cl);
 928         if (!rets)
 929                 cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
 930
 931         mei_io_cb_free(cb);
 932         return rets;
 933 }
 934
 935 /**
 936  * mei_cl_disconnect - disconnect host client from the me one
 937  *
 938  * @cl: host client
 939  *
 940  * Locking: called under "dev->device_lock" lock
 941  *
 942  * Return: 0 on success, <0 on failure.
 943  */
 944 int mei_cl_disconnect(struct mei_cl *cl)
 945 {
 946         struct mei_device *dev;
 947         int rets;
 948
 949         if (WARN_ON(!cl || !cl->dev))
 950                 return -ENODEV;
 951
 952         dev = cl->dev;
 953
 954         cl_dbg(dev, cl, "disconnecting");
 955
 956         if (!mei_cl_is_connected(cl))
 957                 return 0;
 958
 959         if (mei_cl_is_fixed_address(cl)) {
 960                 mei_cl_set_disconnected(cl);
 961                 return 0;
 962         }
 963
 964         if (dev->dev_state == MEI_DEV_POWER_DOWN) {
 965                 cl_dbg(dev, cl, "Device is powering down, don't bother with disconnection\n");
 966                 mei_cl_set_disconnected(cl);
 967                 return 0;
 968         }
 969
 970         rets = pm_runtime_get(dev->dev);
 971         if (rets < 0 && rets != -EINPROGRESS) {
 972                 pm_runtime_put_noidle(dev->dev);
 973                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
 974                 return rets;
 975         }
 976
 977         rets = __mei_cl_disconnect(cl);
 978
 979         cl_dbg(dev, cl, "rpm: autosuspend\n");
 980         pm_runtime_mark_last_busy(dev->dev);
 981         pm_runtime_put_autosuspend(dev->dev);
 982
 983         return rets;
 984 }
 985
 986
 987 /**
 988  * mei_cl_is_other_connecting - checks if other
 989  *    client with the same me client id is connecting
 990  *
 991  * @cl: private data of the file object
 992  *
 993  * Return: true if other client is connected, false - otherwise.
 994  */
 995 static bool mei_cl_is_other_connecting(struct mei_cl *cl)
 996 {
 997         struct mei_device *dev;
 998         struct mei_cl_cb *cb;
 999
1000         dev = cl->dev;
1001
1002         list_for_each_entry(cb, &dev->ctrl_rd_list, list) {
1003                 if (cb->fop_type == MEI_FOP_CONNECT &&
1004                     mei_cl_me_id(cl) == mei_cl_me_id(cb->cl))
1005                         return true;
1006         }
1007
1008         return false;
1009 }
1010
1011 /**
1012  * mei_cl_send_connect - send connect request
1013  *
1014  * @cl: host client
1015  * @cb: callback block
1016  *
1017  * Return: 0, OK; otherwise, error.
1018  */
1019 static int mei_cl_send_connect(struct mei_cl *cl, struct mei_cl_cb *cb)
1020 {
1021         struct mei_device *dev;
1022         int ret;
1023
1024         dev = cl->dev;
1025
1026         ret = mei_hbm_cl_connect_req(dev, cl);
1027         cl->status = ret;
1028         if (ret) {
1029                 cl->state = MEI_FILE_DISCONNECT_REPLY;
1030                 return ret;
1031         }
1032
1033         list_move_tail(&cb->list, &dev->ctrl_rd_list);
1034         cl->timer_count = MEI_CONNECT_TIMEOUT;
1035         mei_schedule_stall_timer(dev);
1036         return 0;
1037 }
1038
1039 /**
1040  * mei_cl_irq_connect - send connect request in irq_thread context
1041  *
1042  * @cl: host client
1043  * @cb: callback block
1044  * @cmpl_list: complete list
1045  *
1046  * Return: 0, OK; otherwise, error.
1047  */
1048 int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
1049                        struct list_head *cmpl_list)
1050 {
1051         struct mei_device *dev = cl->dev;
1052         u32 msg_slots;
1053         int slots;
1054         int rets;
1055
1056         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1057         slots = mei_hbuf_empty_slots(dev);
1058
1059         if (mei_cl_is_other_connecting(cl))
1060                 return 0;
1061
1062         if (slots < msg_slots)
1063                 return -EMSGSIZE;
1064
1065         rets = mei_cl_send_connect(cl, cb);
1066         if (rets)
1067                 list_move_tail(&cb->list, cmpl_list);
1068
1069         return rets;
1070 }
1071
1072 /**
1073  * mei_cl_connect - connect host client to the me one
1074  *
1075  * @cl: host client
1076  * @me_cl: me client
1077  * @fp: pointer to file structure
1078  *
1079  * Locking: called under "dev->device_lock" lock
1080  *
1081  * Return: 0 on success, <0 on failure.
1082  */
1083 int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
1084                    const struct file *fp)
1085 {
1086         struct mei_device *dev;
1087         struct mei_cl_cb *cb;
1088         int rets;
1089
1090         if (WARN_ON(!cl || !cl->dev || !me_cl))
1091                 return -ENODEV;
1092
1093         dev = cl->dev;
1094
1095         rets = mei_cl_set_connecting(cl, me_cl);
1096         if (rets)
1097                 goto nortpm;
1098
1099         if (mei_cl_is_fixed_address(cl)) {
1100                 cl->state = MEI_FILE_CONNECTED;
1101                 rets = 0;
1102                 goto nortpm;
1103         }
1104
1105         rets = pm_runtime_get(dev->dev);
1106         if (rets < 0 && rets != -EINPROGRESS) {
1107                 pm_runtime_put_noidle(dev->dev);
1108                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1109                 goto nortpm;
1110         }
1111
1112         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_CONNECT, fp);
1113         if (!cb) {
1114                 rets = -ENOMEM;
1115                 goto out;
1116         }
1117
1118         /* run hbuf acquire last so we don't have to undo */
1119         if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
1120                 rets = mei_cl_send_connect(cl, cb);
1121                 if (rets)
1122                         goto out;
1123         }
1124
1125         mutex_unlock(&dev->device_lock);
1126         wait_event_timeout(cl->wait,
1127                         (cl->state == MEI_FILE_CONNECTED ||
1128                          cl->state == MEI_FILE_DISCONNECTED ||
1129                          cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
1130                          cl->state == MEI_FILE_DISCONNECT_REPLY),
1131                         mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1132         mutex_lock(&dev->device_lock);
1133
1134         if (!mei_cl_is_connected(cl)) {
1135                 if (cl->state == MEI_FILE_DISCONNECT_REQUIRED) {
1136                         mei_io_list_flush_cl(&dev->ctrl_rd_list, cl);
1137                         mei_io_list_flush_cl(&dev->ctrl_wr_list, cl);
1138                          /* ignore disconnect return valuue;
1139                           * in case of failure reset will be invoked
1140                           */
1141                         __mei_cl_disconnect(cl);
1142                         rets = -EFAULT;
1143                         goto out;
1144                 }
1145
1146                 /* timeout or something went really wrong */
1147                 if (!cl->status)
1148                         cl->status = -EFAULT;
1149         }
1150
1151         rets = cl->status;
1152 out:
1153         cl_dbg(dev, cl, "rpm: autosuspend\n");
1154         pm_runtime_mark_last_busy(dev->dev);
1155         pm_runtime_put_autosuspend(dev->dev);
1156
1157         mei_io_cb_free(cb);
1158
1159 nortpm:
1160         if (!mei_cl_is_connected(cl))
1161                 mei_cl_set_disconnected(cl);
1162
1163         return rets;
1164 }
1165
1166 /**
1167  * mei_cl_alloc_linked - allocate and link host client
1168  *
1169  * @dev: the device structure
1170  *
1171  * Return: cl on success ERR_PTR on failure
1172  */
1173 struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev)
1174 {
1175         struct mei_cl *cl;
1176         int ret;
1177
1178         cl = mei_cl_allocate(dev);
1179         if (!cl) {
1180                 ret = -ENOMEM;
1181                 goto err;
1182         }
1183
1184         ret = mei_cl_link(cl);
1185         if (ret)
1186                 goto err;
1187
1188         return cl;
1189 err:
1190         kfree(cl);
1191         return ERR_PTR(ret);
1192 }
1193
1194 /**
1195  * mei_cl_tx_flow_ctrl_creds - checks flow_control credits for cl.
1196  *
1197  * @cl: host client
1198  *
1199  * Return: 1 if tx_flow_ctrl_creds >0, 0 - otherwise.
1200  */
1201 static int mei_cl_tx_flow_ctrl_creds(struct mei_cl *cl)
1202 {
1203         if (WARN_ON(!cl || !cl->me_cl))
1204                 return -EINVAL;
1205
1206         if (cl->tx_flow_ctrl_creds > 0)
1207                 return 1;
1208
1209         if (mei_cl_is_fixed_address(cl))
1210                 return 1;
1211
1212         if (mei_cl_is_single_recv_buf(cl)) {
1213                 if (cl->me_cl->tx_flow_ctrl_creds > 0)
1214                         return 1;
1215         }
1216         return 0;
1217 }
1218
1219 /**
1220  * mei_cl_tx_flow_ctrl_creds_reduce - reduces transmit flow control credits
1221  *   for a client
1222  *
1223  * @cl: host client
1224  *
1225  * Return:
1226  *      0 on success
1227  *      -EINVAL when ctrl credits are <= 0
1228  */
1229 static int mei_cl_tx_flow_ctrl_creds_reduce(struct mei_cl *cl)
1230 {
1231         if (WARN_ON(!cl || !cl->me_cl))
1232                 return -EINVAL;
1233
1234         if (mei_cl_is_fixed_address(cl))
1235                 return 0;
1236
1237         if (mei_cl_is_single_recv_buf(cl)) {
1238                 if (WARN_ON(cl->me_cl->tx_flow_ctrl_creds <= 0))
1239                         return -EINVAL;
1240                 cl->me_cl->tx_flow_ctrl_creds--;
1241         } else {
1242                 if (WARN_ON(cl->tx_flow_ctrl_creds <= 0))
1243                         return -EINVAL;
1244                 cl->tx_flow_ctrl_creds--;
1245         }
1246         return 0;
1247 }
1248
1249 /**
1250  *  mei_cl_notify_fop2req - convert fop to proper request
1251  *
1252  * @fop: client notification start response command
1253  *
1254  * Return:  MEI_HBM_NOTIFICATION_START/STOP
1255  */
1256 u8 mei_cl_notify_fop2req(enum mei_cb_file_ops fop)
1257 {
1258         if (fop == MEI_FOP_NOTIFY_START)
1259                 return MEI_HBM_NOTIFICATION_START;
1260         else
1261                 return MEI_HBM_NOTIFICATION_STOP;
1262 }
1263
1264 /**
1265  *  mei_cl_notify_req2fop - convert notification request top file operation type
1266  *
1267  * @req: hbm notification request type
1268  *
1269  * Return:  MEI_FOP_NOTIFY_START/STOP
1270  */
1271 enum mei_cb_file_ops mei_cl_notify_req2fop(u8 req)
1272 {
1273         if (req == MEI_HBM_NOTIFICATION_START)
1274                 return MEI_FOP_NOTIFY_START;
1275         else
1276                 return MEI_FOP_NOTIFY_STOP;
1277 }
1278
1279 /**
1280  * mei_cl_irq_notify - send notification request in irq_thread context
1281  *
1282  * @cl: client
1283  * @cb: callback block.
1284  * @cmpl_list: complete list.
1285  *
1286  * Return: 0 on such and error otherwise.
1287  */
1288 int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
1289                       struct list_head *cmpl_list)
1290 {
1291         struct mei_device *dev = cl->dev;
1292         u32 msg_slots;
1293         int slots;
1294         int ret;
1295         bool request;
1296
1297         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1298         slots = mei_hbuf_empty_slots(dev);
1299
1300         if (slots < msg_slots)
1301                 return -EMSGSIZE;
1302
1303         request = mei_cl_notify_fop2req(cb->fop_type);
1304         ret = mei_hbm_cl_notify_req(dev, cl, request);
1305         if (ret) {
1306                 cl->status = ret;
1307                 list_move_tail(&cb->list, cmpl_list);
1308                 return ret;
1309         }
1310
1311         list_move_tail(&cb->list, &dev->ctrl_rd_list);
1312         return 0;
1313 }
1314
1315 /**
1316  * mei_cl_notify_request - send notification stop/start request
1317  *
1318  * @cl: host client
1319  * @fp: associate request with file
1320  * @request: 1 for start or 0 for stop
1321  *
1322  * Locking: called under "dev->device_lock" lock
1323  *
1324  * Return: 0 on such and error otherwise.
1325  */
1326 int mei_cl_notify_request(struct mei_cl *cl,
1327                           const struct file *fp, u8 request)
1328 {
1329         struct mei_device *dev;
1330         struct mei_cl_cb *cb;
1331         enum mei_cb_file_ops fop_type;
1332         int rets;
1333
1334         if (WARN_ON(!cl || !cl->dev))
1335                 return -ENODEV;
1336
1337         dev = cl->dev;
1338
1339         if (!dev->hbm_f_ev_supported) {
1340                 cl_dbg(dev, cl, "notifications not supported\n");
1341                 return -EOPNOTSUPP;
1342         }
1343
1344         if (!mei_cl_is_connected(cl))
1345                 return -ENODEV;
1346
1347         rets = pm_runtime_get(dev->dev);
1348         if (rets < 0 && rets != -EINPROGRESS) {
1349                 pm_runtime_put_noidle(dev->dev);
1350                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1351                 return rets;
1352         }
1353
1354         fop_type = mei_cl_notify_req2fop(request);
1355         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, fop_type, fp);
1356         if (!cb) {
1357                 rets = -ENOMEM;
1358                 goto out;
1359         }
1360
1361         if (mei_hbuf_acquire(dev)) {
1362                 if (mei_hbm_cl_notify_req(dev, cl, request)) {
1363                         rets = -ENODEV;
1364                         goto out;
1365                 }
1366                 list_move_tail(&cb->list, &dev->ctrl_rd_list);
1367         }
1368
1369         mutex_unlock(&dev->device_lock);
1370         wait_event_timeout(cl->wait,
1371                            cl->notify_en == request || !mei_cl_is_connected(cl),
1372                            mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1373         mutex_lock(&dev->device_lock);
1374
1375         if (cl->notify_en != request && !cl->status)
1376                 cl->status = -EFAULT;
1377
1378         rets = cl->status;
1379
1380 out:
1381         cl_dbg(dev, cl, "rpm: autosuspend\n");
1382         pm_runtime_mark_last_busy(dev->dev);
1383         pm_runtime_put_autosuspend(dev->dev);
1384
1385         mei_io_cb_free(cb);
1386         return rets;
1387 }
1388
1389 /**
1390  * mei_cl_notify - raise notification
1391  *
1392  * @cl: host client
1393  *
1394  * Locking: called under "dev->device_lock" lock
1395  */
1396 void mei_cl_notify(struct mei_cl *cl)
1397 {
1398         struct mei_device *dev;
1399
1400         if (!cl || !cl->dev)
1401                 return;
1402
1403         dev = cl->dev;
1404
1405         if (!cl->notify_en)
1406                 return;
1407
1408         cl_dbg(dev, cl, "notify event");
1409         cl->notify_ev = true;
1410         if (!mei_cl_bus_notify_event(cl))
1411                 wake_up_interruptible(&cl->ev_wait);
1412
1413         if (cl->ev_async)
1414                 kill_fasync(&cl->ev_async, SIGIO, POLL_PRI);
1415
1416 }
1417
1418 /**
1419  * mei_cl_notify_get - get or wait for notification event
1420  *
1421  * @cl: host client
1422  * @block: this request is blocking
1423  * @notify_ev: true if notification event was received
1424  *
1425  * Locking: called under "dev->device_lock" lock
1426  *
1427  * Return: 0 on such and error otherwise.
1428  */
1429 int mei_cl_notify_get(struct mei_cl *cl, bool block, bool *notify_ev)
1430 {
1431         struct mei_device *dev;
1432         int rets;
1433
1434         *notify_ev = false;
1435
1436         if (WARN_ON(!cl || !cl->dev))
1437                 return -ENODEV;
1438
1439         dev = cl->dev;
1440
1441         if (!dev->hbm_f_ev_supported) {
1442                 cl_dbg(dev, cl, "notifications not supported\n");
1443                 return -EOPNOTSUPP;
1444         }
1445
1446         if (!mei_cl_is_connected(cl))
1447                 return -ENODEV;
1448
1449         if (cl->notify_ev)
1450                 goto out;
1451
1452         if (!block)
1453                 return -EAGAIN;
1454
1455         mutex_unlock(&dev->device_lock);
1456         rets = wait_event_interruptible(cl->ev_wait, cl->notify_ev);
1457         mutex_lock(&dev->device_lock);
1458
1459         if (rets < 0)
1460                 return rets;
1461
1462 out:
1463         *notify_ev = cl->notify_ev;
1464         cl->notify_ev = false;
1465         return 0;
1466 }
1467
1468 /**
1469  * mei_cl_read_start - the start read client message function.
1470  *
1471  * @cl: host client
1472  * @length: number of bytes to read
1473  * @fp: pointer to file structure
1474  *
1475  * Return: 0 on success, <0 on failure.
1476  */
1477 int mei_cl_read_start(struct mei_cl *cl, size_t length, const struct file *fp)
1478 {
1479         struct mei_device *dev;
1480         struct mei_cl_cb *cb;
1481         int rets;
1482
1483         if (WARN_ON(!cl || !cl->dev))
1484                 return -ENODEV;
1485
1486         dev = cl->dev;
1487
1488         if (!mei_cl_is_connected(cl))
1489                 return -ENODEV;
1490
1491         if (!mei_me_cl_is_active(cl->me_cl)) {
1492                 cl_err(dev, cl, "no such me client\n");
1493                 return  -ENOTTY;
1494         }
1495
1496         if (mei_cl_is_fixed_address(cl))
1497                 return 0;
1498
1499         /* HW currently supports only one pending read */
1500         if (cl->rx_flow_ctrl_creds)
1501                 return -EBUSY;
1502
1503         cb = mei_cl_enqueue_ctrl_wr_cb(cl, length, MEI_FOP_READ, fp);
1504         if (!cb)
1505                 return -ENOMEM;
1506
1507         rets = pm_runtime_get(dev->dev);
1508         if (rets < 0 && rets != -EINPROGRESS) {
1509                 pm_runtime_put_noidle(dev->dev);
1510                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1511                 goto nortpm;
1512         }
1513
1514         rets = 0;
1515         if (mei_hbuf_acquire(dev)) {
1516                 rets = mei_hbm_cl_flow_control_req(dev, cl);
1517                 if (rets < 0)
1518                         goto out;
1519
1520                 list_move_tail(&cb->list, &cl->rd_pending);
1521         }
1522         cl->rx_flow_ctrl_creds++;
1523
1524 out:
1525         cl_dbg(dev, cl, "rpm: autosuspend\n");
1526         pm_runtime_mark_last_busy(dev->dev);
1527         pm_runtime_put_autosuspend(dev->dev);
1528 nortpm:
1529         if (rets)
1530                 mei_io_cb_free(cb);
1531
1532         return rets;
1533 }
1534
1535 /**
1536  * mei_cl_irq_write - write a message to device
1537  *      from the interrupt thread context
1538  *
1539  * @cl: client
1540  * @cb: callback block.
1541  * @cmpl_list: complete list.
1542  *
1543  * Return: 0, OK; otherwise error.
1544  */
1545 int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
1546                      struct list_head *cmpl_list)
1547 {
1548         struct mei_device *dev;
1549         struct mei_msg_data *buf;
1550         struct mei_msg_hdr mei_hdr;
1551         size_t len;
1552         u32 msg_slots;
1553         int slots;
1554         int rets;
1555         bool first_chunk;
1556
1557         if (WARN_ON(!cl || !cl->dev))
1558                 return -ENODEV;
1559
1560         dev = cl->dev;
1561
1562         buf = &cb->buf;
1563
1564         first_chunk = cb->buf_idx == 0;
1565
1566         rets = first_chunk ? mei_cl_tx_flow_ctrl_creds(cl) : 1;
1567         if (rets < 0)
1568                 goto err;
1569
1570         if (rets == 0) {
1571                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1572                 return 0;
1573         }
1574
1575         slots = mei_hbuf_empty_slots(dev);
1576         len = buf->size - cb->buf_idx;
1577         msg_slots = mei_data2slots(len);
1578
1579         mei_hdr.host_addr = mei_cl_host_addr(cl);
1580         mei_hdr.me_addr = mei_cl_me_id(cl);
1581         mei_hdr.reserved = 0;
1582         mei_hdr.internal = cb->internal;
1583
1584         if (slots >= msg_slots) {
1585                 mei_hdr.length = len;
1586                 mei_hdr.msg_complete = 1;
1587         /* Split the message only if we can write the whole host buffer */
1588         } else if (slots == dev->hbuf_depth) {
1589                 msg_slots = slots;
1590                 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
1591                 mei_hdr.length = len;
1592                 mei_hdr.msg_complete = 0;
1593         } else {
1594                 /* wait for next time the host buffer is empty */
1595                 return 0;
1596         }
1597
1598         cl_dbg(dev, cl, "buf: size = %zu idx = %zu\n",
1599                         cb->buf.size, cb->buf_idx);
1600
1601         rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
1602         if (rets)
1603                 goto err;
1604
1605         cl->status = 0;
1606         cl->writing_state = MEI_WRITING;
1607         cb->buf_idx += mei_hdr.length;
1608         cb->completed = mei_hdr.msg_complete == 1;
1609
1610         if (first_chunk) {
1611                 if (mei_cl_tx_flow_ctrl_creds_reduce(cl)) {
1612                         rets = -EIO;
1613                         goto err;
1614                 }
1615         }
1616
1617         if (mei_hdr.msg_complete)
1618                 list_move_tail(&cb->list, &dev->write_waiting_list);
1619
1620         return 0;
1621
1622 err:
1623         cl->status = rets;
1624         list_move_tail(&cb->list, cmpl_list);
1625         return rets;
1626 }
1627
1628 /**
1629  * mei_cl_write - submit a write cb to mei device
1630  *      assumes device_lock is locked
1631  *
1632  * @cl: host client
1633  * @cb: write callback with filled data
1634  *
1635  * Return: number of bytes sent on success, <0 on failure.
1636  */
1637 int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb)
1638 {
1639         struct mei_device *dev;
1640         struct mei_msg_data *buf;
1641         struct mei_msg_hdr mei_hdr;
1642         int size;
1643         int rets;
1644         bool blocking;
1645
1646         if (WARN_ON(!cl || !cl->dev))
1647                 return -ENODEV;
1648
1649         if (WARN_ON(!cb))
1650                 return -EINVAL;
1651
1652         dev = cl->dev;
1653
1654         buf = &cb->buf;
1655         size = buf->size;
1656         blocking = cb->blocking;
1657
1658         cl_dbg(dev, cl, "size=%d\n", size);
1659
1660         rets = pm_runtime_get(dev->dev);
1661         if (rets < 0 && rets != -EINPROGRESS) {
1662                 pm_runtime_put_noidle(dev->dev);
1663                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1664                 goto free;
1665         }
1666
1667         cb->buf_idx = 0;
1668         cl->writing_state = MEI_IDLE;
1669
1670         mei_hdr.host_addr = mei_cl_host_addr(cl);
1671         mei_hdr.me_addr = mei_cl_me_id(cl);
1672         mei_hdr.reserved = 0;
1673         mei_hdr.msg_complete = 0;
1674         mei_hdr.internal = cb->internal;
1675
1676         rets = mei_cl_tx_flow_ctrl_creds(cl);
1677         if (rets < 0)
1678                 goto err;
1679
1680         if (rets == 0) {
1681                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1682                 rets = size;
1683                 goto out;
1684         }
1685         if (!mei_hbuf_acquire(dev)) {
1686                 cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
1687                 rets = size;
1688                 goto out;
1689         }
1690
1691         /* Check for a maximum length */
1692         if (size > mei_hbuf_max_len(dev)) {
1693                 mei_hdr.length = mei_hbuf_max_len(dev);
1694                 mei_hdr.msg_complete = 0;
1695         } else {
1696                 mei_hdr.length = size;
1697                 mei_hdr.msg_complete = 1;
1698         }
1699
1700         rets = mei_write_message(dev, &mei_hdr, buf->data);
1701         if (rets)
1702                 goto err;
1703
1704         rets = mei_cl_tx_flow_ctrl_creds_reduce(cl);
1705         if (rets)
1706                 goto err;
1707
1708         cl->writing_state = MEI_WRITING;
1709         cb->buf_idx = mei_hdr.length;
1710         cb->completed = mei_hdr.msg_complete == 1;
1711
1712 out:
1713         if (mei_hdr.msg_complete)
1714                 mei_tx_cb_enqueue(cb, &dev->write_waiting_list);
1715         else
1716                 mei_tx_cb_enqueue(cb, &dev->write_list);
1717
1718         cb = NULL;
1719         if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
1720
1721                 mutex_unlock(&dev->device_lock);
1722                 rets = wait_event_interruptible(cl->tx_wait,
1723                                 cl->writing_state == MEI_WRITE_COMPLETE ||
1724                                 (!mei_cl_is_connected(cl)));
1725                 mutex_lock(&dev->device_lock);
1726                 /* wait_event_interruptible returns -ERESTARTSYS */
1727                 if (rets) {
1728                         if (signal_pending(current))
1729                                 rets = -EINTR;
1730                         goto err;
1731                 }
1732                 if (cl->writing_state != MEI_WRITE_COMPLETE) {
1733                         rets = -EFAULT;
1734                         goto err;
1735                 }
1736         }
1737
1738         rets = size;
1739 err:
1740         cl_dbg(dev, cl, "rpm: autosuspend\n");
1741         pm_runtime_mark_last_busy(dev->dev);
1742         pm_runtime_put_autosuspend(dev->dev);
1743 free:
1744         mei_io_cb_free(cb);
1745
1746         return rets;
1747 }
1748
1749
1750 /**
1751  * mei_cl_complete - processes completed operation for a client
1752  *
1753  * @cl: private data of the file object.
1754  * @cb: callback block.
1755  */
1756 void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
1757 {
1758         struct mei_device *dev = cl->dev;
1759
1760         switch (cb->fop_type) {
1761         case MEI_FOP_WRITE:
1762                 mei_tx_cb_dequeue(cb);
1763                 cl->writing_state = MEI_WRITE_COMPLETE;
1764                 if (waitqueue_active(&cl->tx_wait)) {
1765                         wake_up_interruptible(&cl->tx_wait);
1766                 } else {
1767                         pm_runtime_mark_last_busy(dev->dev);
1768                         pm_request_autosuspend(dev->dev);
1769                 }
1770                 break;
1771
1772         case MEI_FOP_READ:
1773                 list_add_tail(&cb->list, &cl->rd_completed);
1774                 if (!mei_cl_is_fixed_address(cl) &&
1775                     !WARN_ON(!cl->rx_flow_ctrl_creds))
1776                         cl->rx_flow_ctrl_creds--;
1777                 if (!mei_cl_bus_rx_event(cl))
1778                         wake_up_interruptible(&cl->rx_wait);
1779                 break;
1780
1781         case MEI_FOP_CONNECT:
1782         case MEI_FOP_DISCONNECT:
1783         case MEI_FOP_NOTIFY_STOP:
1784         case MEI_FOP_NOTIFY_START:
1785                 if (waitqueue_active(&cl->wait))
1786                         wake_up(&cl->wait);
1787
1788                 break;
1789         case MEI_FOP_DISCONNECT_RSP:
1790                 mei_io_cb_free(cb);
1791                 mei_cl_set_disconnected(cl);
1792                 break;
1793         default:
1794                 BUG_ON(0);
1795         }
1796 }
1797
1798
1799 /**
1800  * mei_cl_all_disconnect - disconnect forcefully all connected clients
1801  *
1802  * @dev: mei device
1803  */
1804 void mei_cl_all_disconnect(struct mei_device *dev)
1805 {
1806         struct mei_cl *cl;
1807
1808         list_for_each_entry(cl, &dev->file_list, link)
1809                 mei_cl_set_disconnected(cl);
1810 }