drivers/misc/mei/client.c

   1 /*
   2  *
   3  * Intel Management Engine Interface (Intel MEI) Linux driver
   4  * Copyright (c) 2003-2012, Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  */
  16
  17 #include <linux/sched.h>
  18 #include <linux/wait.h>
  19 #include <linux/delay.h>
  20 #include <linux/slab.h>
  21 #include <linux/pm_runtime.h>
  22
  23 #include <linux/mei.h>
  24
  25 #include "mei_dev.h"
  26 #include "hbm.h"
  27 #include "client.h"
  28
  29 /**
  30  * mei_me_cl_init - initialize me client
  31  *
  32  * @me_cl: me client
  33  */
  34 void mei_me_cl_init(struct mei_me_client *me_cl)
  35 {
  36         INIT_LIST_HEAD(&me_cl->list);
  37         kref_init(&me_cl->refcnt);
  38 }
  39
  40 /**
  41  * mei_me_cl_get - increases me client refcount
  42  *
  43  * @me_cl: me client
  44  *
  45  * Locking: called under "dev->device_lock" lock
  46  *
  47  * Return: me client or NULL
  48  */
  49 struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl)
  50 {
  51         if (me_cl && kref_get_unless_zero(&me_cl->refcnt))
  52                 return me_cl;
  53
  54         return NULL;
  55 }
  56
  57 /**
  58  * mei_me_cl_release - free me client
  59  *
  60  * Locking: called under "dev->device_lock" lock
  61  *
  62  * @ref: me_client refcount
  63  */
  64 static void mei_me_cl_release(struct kref *ref)
  65 {
  66         struct mei_me_client *me_cl =
  67                 container_of(ref, struct mei_me_client, refcnt);
  68
  69         kfree(me_cl);
  70 }
  71
  72 /**
  73  * mei_me_cl_put - decrease me client refcount and free client if necessary
  74  *
  75  * Locking: called under "dev->device_lock" lock
  76  *
  77  * @me_cl: me client
  78  */
  79 void mei_me_cl_put(struct mei_me_client *me_cl)
  80 {
  81         if (me_cl)
  82                 kref_put(&me_cl->refcnt, mei_me_cl_release);
  83 }
  84
  85 /**
  86  * __mei_me_cl_del  - delete me client from the list and decrease
  87  *     reference counter
  88  *
  89  * @dev: mei device
  90  * @me_cl: me client
  91  *
  92  * Locking: dev->me_clients_rwsem
  93  */
  94 static void __mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
  95 {
  96         if (!me_cl)
  97                 return;
  98
  99         list_del_init(&me_cl->list);
 100         mei_me_cl_put(me_cl);
 101 }
 102
 103 /**
 104  * mei_me_cl_del - delete me client from the list and decrease
 105  *     reference counter
 106  *
 107  * @dev: mei device
 108  * @me_cl: me client
 109  */
 110 void mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
 111 {
 112         down_write(&dev->me_clients_rwsem);
 113         __mei_me_cl_del(dev, me_cl);
 114         up_write(&dev->me_clients_rwsem);
 115 }
 116
 117 /**
 118  * mei_me_cl_add - add me client to the list
 119  *
 120  * @dev: mei device
 121  * @me_cl: me client
 122  */
 123 void mei_me_cl_add(struct mei_device *dev, struct mei_me_client *me_cl)
 124 {
 125         down_write(&dev->me_clients_rwsem);
 126         list_add(&me_cl->list, &dev->me_clients);
 127         up_write(&dev->me_clients_rwsem);
 128 }
 129
 130 /**
 131  * __mei_me_cl_by_uuid - locate me client by uuid
 132  *      increases ref count
 133  *
 134  * @dev: mei device
 135  * @uuid: me client uuid
 136  *
 137  * Return: me client or NULL if not found
 138  *
 139  * Locking: dev->me_clients_rwsem
 140  */
 141 static struct mei_me_client *__mei_me_cl_by_uuid(struct mei_device *dev,
 142                                         const uuid_le *uuid)
 143 {
 144         struct mei_me_client *me_cl;
 145         const uuid_le *pn;
 146
 147         WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
 148
 149         list_for_each_entry(me_cl, &dev->me_clients, list) {
 150                 pn = &me_cl->props.protocol_name;
 151                 if (uuid_le_cmp(*uuid, *pn) == 0)
 152                         return mei_me_cl_get(me_cl);
 153         }
 154
 155         return NULL;
 156 }
 157
 158 /**
 159  * mei_me_cl_by_uuid - locate me client by uuid
 160  *      increases ref count
 161  *
 162  * @dev: mei device
 163  * @uuid: me client uuid
 164  *
 165  * Return: me client or NULL if not found
 166  *
 167  * Locking: dev->me_clients_rwsem
 168  */
 169 struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev,
 170                                         const uuid_le *uuid)
 171 {
 172         struct mei_me_client *me_cl;
 173
 174         down_read(&dev->me_clients_rwsem);
 175         me_cl = __mei_me_cl_by_uuid(dev, uuid);
 176         up_read(&dev->me_clients_rwsem);
 177
 178         return me_cl;
 179 }
 180
 181 /**
 182  * mei_me_cl_by_id - locate me client by client id
 183  *      increases ref count
 184  *
 185  * @dev: the device structure
 186  * @client_id: me client id
 187  *
 188  * Return: me client or NULL if not found
 189  *
 190  * Locking: dev->me_clients_rwsem
 191  */
 192 struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
 193 {
 194
 195         struct mei_me_client *__me_cl, *me_cl = NULL;
 196
 197         down_read(&dev->me_clients_rwsem);
 198         list_for_each_entry(__me_cl, &dev->me_clients, list) {
 199                 if (__me_cl->client_id == client_id) {
 200                         me_cl = mei_me_cl_get(__me_cl);
 201                         break;
 202                 }
 203         }
 204         up_read(&dev->me_clients_rwsem);
 205
 206         return me_cl;
 207 }
 208
 209 /**
 210  * __mei_me_cl_by_uuid_id - locate me client by client id and uuid
 211  *      increases ref count
 212  *
 213  * @dev: the device structure
 214  * @uuid: me client uuid
 215  * @client_id: me client id
 216  *
 217  * Return: me client or null if not found
 218  *
 219  * Locking: dev->me_clients_rwsem
 220  */
 221 static struct mei_me_client *__mei_me_cl_by_uuid_id(struct mei_device *dev,
 222                                            const uuid_le *uuid, u8 client_id)
 223 {
 224         struct mei_me_client *me_cl;
 225         const uuid_le *pn;
 226
 227         WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
 228
 229         list_for_each_entry(me_cl, &dev->me_clients, list) {
 230                 pn = &me_cl->props.protocol_name;
 231                 if (uuid_le_cmp(*uuid, *pn) == 0 &&
 232                     me_cl->client_id == client_id)
 233                         return mei_me_cl_get(me_cl);
 234         }
 235
 236         return NULL;
 237 }
 238
 239
 240 /**
 241  * mei_me_cl_by_uuid_id - locate me client by client id and uuid
 242  *      increases ref count
 243  *
 244  * @dev: the device structure
 245  * @uuid: me client uuid
 246  * @client_id: me client id
 247  *
 248  * Return: me client or null if not found
 249  */
 250 struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
 251                                            const uuid_le *uuid, u8 client_id)
 252 {
 253         struct mei_me_client *me_cl;
 254
 255         down_read(&dev->me_clients_rwsem);
 256         me_cl = __mei_me_cl_by_uuid_id(dev, uuid, client_id);
 257         up_read(&dev->me_clients_rwsem);
 258
 259         return me_cl;
 260 }
 261
 262 /**
 263  * mei_me_cl_rm_by_uuid - remove all me clients matching uuid
 264  *
 265  * @dev: the device structure
 266  * @uuid: me client uuid
 267  *
 268  * Locking: called under "dev->device_lock" lock
 269  */
 270 void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid)
 271 {
 272         struct mei_me_client *me_cl;
 273
 274         dev_dbg(dev->dev, "remove %pUl\n", uuid);
 275
 276         down_write(&dev->me_clients_rwsem);
 277         me_cl = __mei_me_cl_by_uuid(dev, uuid);
 278         __mei_me_cl_del(dev, me_cl);
 279         up_write(&dev->me_clients_rwsem);
 280 }
 281
 282 /**
 283  * mei_me_cl_rm_by_uuid_id - remove all me clients matching client id
 284  *
 285  * @dev: the device structure
 286  * @uuid: me client uuid
 287  * @id: me client id
 288  *
 289  * Locking: called under "dev->device_lock" lock
 290  */
 291 void mei_me_cl_rm_by_uuid_id(struct mei_device *dev, const uuid_le *uuid, u8 id)
 292 {
 293         struct mei_me_client *me_cl;
 294
 295         dev_dbg(dev->dev, "remove %pUl %d\n", uuid, id);
 296
 297         down_write(&dev->me_clients_rwsem);
 298         me_cl = __mei_me_cl_by_uuid_id(dev, uuid, id);
 299         __mei_me_cl_del(dev, me_cl);
 300         up_write(&dev->me_clients_rwsem);
 301 }
 302
 303 /**
 304  * mei_me_cl_rm_all - remove all me clients
 305  *
 306  * @dev: the device structure
 307  *
 308  * Locking: called under "dev->device_lock" lock
 309  */
 310 void mei_me_cl_rm_all(struct mei_device *dev)
 311 {
 312         struct mei_me_client *me_cl, *next;
 313
 314         down_write(&dev->me_clients_rwsem);
 315         list_for_each_entry_safe(me_cl, next, &dev->me_clients, list)
 316                 __mei_me_cl_del(dev, me_cl);
 317         up_write(&dev->me_clients_rwsem);
 318 }
 319
 320 /**
 321  * mei_cl_cmp_id - tells if the clients are the same
 322  *
 323  * @cl1: host client 1
 324  * @cl2: host client 2
 325  *
 326  * Return: true  - if the clients has same host and me ids
 327  *         false - otherwise
 328  */
 329 static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
 330                                 const struct mei_cl *cl2)
 331 {
 332         return cl1 && cl2 &&
 333                 (cl1->host_client_id == cl2->host_client_id) &&
 334                 (mei_cl_me_id(cl1) == mei_cl_me_id(cl2));
 335 }
 336
 337 /**
 338  * mei_io_cb_free - free mei_cb_private related memory
 339  *
 340  * @cb: mei callback struct
 341  */
 342 void mei_io_cb_free(struct mei_cl_cb *cb)
 343 {
 344         if (cb == NULL)
 345                 return;
 346
 347         list_del(&cb->list);
 348         kfree(cb->buf.data);
 349         kfree(cb);
 350 }
 351
 352 /**
 353  * mei_io_cb_init - allocate and initialize io callback
 354  *
 355  * @cl: mei client
 356  * @type: operation type
 357  * @fp: pointer to file structure
 358  *
 359  * Return: mei_cl_cb pointer or NULL;
 360  */
 361 static struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl,
 362                                         enum mei_cb_file_ops type,
 363                                         const struct file *fp)
 364 {
 365         struct mei_cl_cb *cb;
 366
 367         cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
 368         if (!cb)
 369                 return NULL;
 370
 371         INIT_LIST_HEAD(&cb->list);
 372         cb->fp = fp;
 373         cb->cl = cl;
 374         cb->buf_idx = 0;
 375         cb->fop_type = type;
 376         return cb;
 377 }
 378
 379 /**
 380  * __mei_io_list_flush - removes and frees cbs belonging to cl.
 381  *
 382  * @list:  an instance of our list structure
 383  * @cl:    host client, can be NULL for flushing the whole list
 384  * @free:  whether to free the cbs
 385  */
 386 static void __mei_io_list_flush(struct mei_cl_cb *list,
 387                                 struct mei_cl *cl, bool free)
 388 {
 389         struct mei_cl_cb *cb, *next;
 390
 391         /* enable removing everything if no cl is specified */
 392         list_for_each_entry_safe(cb, next, &list->list, list) {
 393                 if (!cl || mei_cl_cmp_id(cl, cb->cl)) {
 394                         list_del_init(&cb->list);
 395                         if (free)
 396                                 mei_io_cb_free(cb);
 397                 }
 398         }
 399 }
 400
 401 /**
 402  * mei_io_list_flush - removes list entry belonging to cl.
 403  *
 404  * @list:  An instance of our list structure
 405  * @cl: host client
 406  */
 407 void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl)
 408 {
 409         __mei_io_list_flush(list, cl, false);
 410 }
 411
 412 /**
 413  * mei_io_list_free - removes cb belonging to cl and free them
 414  *
 415  * @list:  An instance of our list structure
 416  * @cl: host client
 417  */
 418 static inline void mei_io_list_free(struct mei_cl_cb *list, struct mei_cl *cl)
 419 {
 420         __mei_io_list_flush(list, cl, true);
 421 }
 422
 423 /**
 424  * mei_cl_alloc_cb - a convenient wrapper for allocating read cb
 425  *
 426  * @cl: host client
 427  * @length: size of the buffer
 428  * @type: operation type
 429  * @fp: associated file pointer (might be NULL)
 430  *
 431  * Return: cb on success and NULL on failure
 432  */
 433 struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
 434                                   enum mei_cb_file_ops fop_type,
 435                                   const struct file *fp)
 436 {
 437         struct mei_cl_cb *cb;
 438
 439         cb = mei_io_cb_init(cl, fop_type, fp);
 440         if (!cb)
 441                 return NULL;
 442
 443         if (length == 0)
 444                 return cb;
 445
 446         cb->buf.data = kmalloc(length, GFP_KERNEL);
 447         if (!cb->buf.data) {
 448                 mei_io_cb_free(cb);
 449                 return NULL;
 450         }
 451         cb->buf.size = length;
 452
 453         return cb;
 454 }
 455
 456 /**
 457  * mei_cl_enqueue_ctrl_wr_cb - a convenient wrapper for allocating
 458  *     and enqueuing of the control commands cb
 459  *
 460  * @cl: host client
 461  * @length: size of the buffer
 462  * @type: operation type
 463  * @fp: associated file pointer (might be NULL)
 464  *
 465  * Return: cb on success and NULL on failure
 466  * Locking: called under "dev->device_lock" lock
 467  */
 468 struct mei_cl_cb *mei_cl_enqueue_ctrl_wr_cb(struct mei_cl *cl, size_t length,
 469                                             enum mei_cb_file_ops fop_type,
 470                                             const struct file *fp)
 471 {
 472         struct mei_cl_cb *cb;
 473
 474         /* for RX always allocate at least client's mtu */
 475         if (length)
 476                 length = max_t(size_t, length, mei_cl_mtu(cl));
 477
 478         cb = mei_cl_alloc_cb(cl, length, fop_type, fp);
 479         if (!cb)
 480                 return NULL;
 481
 482         list_add_tail(&cb->list, &cl->dev->ctrl_wr_list.list);
 483         return cb;
 484 }
 485
 486 /**
 487  * mei_cl_read_cb - find this cl's callback in the read list
 488  *     for a specific file
 489  *
 490  * @cl: host client
 491  * @fp: file pointer (matching cb file object), may be NULL
 492  *
 493  * Return: cb on success, NULL if cb is not found
 494  */
 495 struct mei_cl_cb *mei_cl_read_cb(const struct mei_cl *cl, const struct file *fp)
 496 {
 497         struct mei_cl_cb *cb;
 498
 499         list_for_each_entry(cb, &cl->rd_completed, list)
 500                 if (!fp || fp == cb->fp)
 501                         return cb;
 502
 503         return NULL;
 504 }
 505
 506 /**
 507  * mei_cl_read_cb_flush - free client's read pending and completed cbs
 508  *   for a specific file
 509  *
 510  * @cl: host client
 511  * @fp: file pointer (matching cb file object), may be NULL
 512  */
 513 void mei_cl_read_cb_flush(const struct mei_cl *cl, const struct file *fp)
 514 {
 515         struct mei_cl_cb *cb, *next;
 516
 517         list_for_each_entry_safe(cb, next, &cl->rd_completed, list)
 518                 if (!fp || fp == cb->fp)
 519                         mei_io_cb_free(cb);
 520
 521
 522         list_for_each_entry_safe(cb, next, &cl->rd_pending, list)
 523                 if (!fp || fp == cb->fp)
 524                         mei_io_cb_free(cb);
 525 }
 526
 527 /**
 528  * mei_cl_flush_queues - flushes queue lists belonging to cl.
 529  *
 530  * @cl: host client
 531  * @fp: file pointer (matching cb file object), may be NULL
 532  *
 533  * Return: 0 on success, -EINVAL if cl or cl->dev is NULL.
 534  */
 535 int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp)
 536 {
 537         struct mei_device *dev;
 538
 539         if (WARN_ON(!cl || !cl->dev))
 540                 return -EINVAL;
 541
 542         dev = cl->dev;
 543
 544         cl_dbg(dev, cl, "remove list entry belonging to cl\n");
 545         mei_io_list_free(&cl->dev->write_list, cl);
 546         mei_io_list_free(&cl->dev->write_waiting_list, cl);
 547         mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
 548         mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
 549         mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
 550
 551         mei_cl_read_cb_flush(cl, fp);
 552
 553         return 0;
 554 }
 555
 556
 557 /**
 558  * mei_cl_init - initializes cl.
 559  *
 560  * @cl: host client to be initialized
 561  * @dev: mei device
 562  */
 563 void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
 564 {
 565         memset(cl, 0, sizeof(struct mei_cl));
 566         init_waitqueue_head(&cl->wait);
 567         init_waitqueue_head(&cl->rx_wait);
 568         init_waitqueue_head(&cl->tx_wait);
 569         init_waitqueue_head(&cl->ev_wait);
 570         INIT_LIST_HEAD(&cl->rd_completed);
 571         INIT_LIST_HEAD(&cl->rd_pending);
 572         INIT_LIST_HEAD(&cl->link);
 573         cl->writing_state = MEI_IDLE;
 574         cl->state = MEI_FILE_INITIALIZING;
 575         cl->dev = dev;
 576 }
 577
 578 /**
 579  * mei_cl_allocate - allocates cl  structure and sets it up.
 580  *
 581  * @dev: mei device
 582  * Return:  The allocated file or NULL on failure
 583  */
 584 struct mei_cl *mei_cl_allocate(struct mei_device *dev)
 585 {
 586         struct mei_cl *cl;
 587
 588         cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
 589         if (!cl)
 590                 return NULL;
 591
 592         mei_cl_init(cl, dev);
 593
 594         return cl;
 595 }
 596
 597 /**
 598  * mei_cl_link - allocate host id in the host map
 599  *
 600  * @cl: host client
 601  *
 602  * Return: 0 on success
 603  *      -EINVAL on incorrect values
 604  *      -EMFILE if open count exceeded.
 605  */
 606 int mei_cl_link(struct mei_cl *cl)
 607 {
 608         struct mei_device *dev;
 609         long open_handle_count;
 610         int id;
 611
 612         if (WARN_ON(!cl || !cl->dev))
 613                 return -EINVAL;
 614
 615         dev = cl->dev;
 616
 617         id = find_first_zero_bit(dev->host_clients_map, MEI_CLIENTS_MAX);
 618         if (id >= MEI_CLIENTS_MAX) {
 619                 dev_err(dev->dev, "id exceeded %d", MEI_CLIENTS_MAX);
 620                 return -EMFILE;
 621         }
 622
 623         open_handle_count = dev->open_handle_count + dev->iamthif_open_count;
 624         if (open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
 625                 dev_err(dev->dev, "open_handle_count exceeded %d",
 626                         MEI_MAX_OPEN_HANDLE_COUNT);
 627                 return -EMFILE;
 628         }
 629
 630         dev->open_handle_count++;
 631
 632         cl->host_client_id = id;
 633         list_add_tail(&cl->link, &dev->file_list);
 634
 635         set_bit(id, dev->host_clients_map);
 636
 637         cl->state = MEI_FILE_INITIALIZING;
 638
 639         cl_dbg(dev, cl, "link cl\n");
 640         return 0;
 641 }
 642
 643 /**
 644  * mei_cl_unlink - remove host client from the list
 645  *
 646  * @cl: host client
 647  *
 648  * Return: always 0
 649  */
 650 int mei_cl_unlink(struct mei_cl *cl)
 651 {
 652         struct mei_device *dev;
 653
 654         /* don't shout on error exit path */
 655         if (!cl)
 656                 return 0;
 657
 658         /* amthif might not be initialized */
 659         if (!cl->dev)
 660                 return 0;
 661
 662         dev = cl->dev;
 663
 664         cl_dbg(dev, cl, "unlink client");
 665
 666         if (dev->open_handle_count > 0)
 667                 dev->open_handle_count--;
 668
 669         /* never clear the 0 bit */
 670         if (cl->host_client_id)
 671                 clear_bit(cl->host_client_id, dev->host_clients_map);
 672
 673         list_del_init(&cl->link);
 674
 675         cl->state = MEI_FILE_INITIALIZING;
 676
 677         return 0;
 678 }
 679
 680 void mei_host_client_init(struct mei_device *dev)
 681 {
 682         dev->dev_state = MEI_DEV_ENABLED;
 683         dev->reset_count = 0;
 684
 685         schedule_work(&dev->bus_rescan_work);
 686
 687         pm_runtime_mark_last_busy(dev->dev);
 688         dev_dbg(dev->dev, "rpm: autosuspend\n");
 689         pm_runtime_autosuspend(dev->dev);
 690 }
 691
 692 /**
 693  * mei_hbuf_acquire - try to acquire host buffer
 694  *
 695  * @dev: the device structure
 696  * Return: true if host buffer was acquired
 697  */
 698 bool mei_hbuf_acquire(struct mei_device *dev)
 699 {
 700         if (mei_pg_state(dev) == MEI_PG_ON ||
 701             mei_pg_in_transition(dev)) {
 702                 dev_dbg(dev->dev, "device is in pg\n");
 703                 return false;
 704         }
 705
 706         if (!dev->hbuf_is_ready) {
 707                 dev_dbg(dev->dev, "hbuf is not ready\n");
 708                 return false;
 709         }
 710
 711         dev->hbuf_is_ready = false;
 712
 713         return true;
 714 }
 715
 716 /**
 717  * mei_cl_wake_all - wake up readers, writers and event waiters so
 718  *                 they can be interrupted
 719  *
 720  * @cl: host client
 721  */
 722 static void mei_cl_wake_all(struct mei_cl *cl)
 723 {
 724         struct mei_device *dev = cl->dev;
 725
 726         /* synchronized under device mutex */
 727         if (waitqueue_active(&cl->rx_wait)) {
 728                 cl_dbg(dev, cl, "Waking up reading client!\n");
 729                 wake_up_interruptible(&cl->rx_wait);
 730         }
 731         /* synchronized under device mutex */
 732         if (waitqueue_active(&cl->tx_wait)) {
 733                 cl_dbg(dev, cl, "Waking up writing client!\n");
 734                 wake_up_interruptible(&cl->tx_wait);
 735         }
 736         /* synchronized under device mutex */
 737         if (waitqueue_active(&cl->ev_wait)) {
 738                 cl_dbg(dev, cl, "Waking up waiting for event clients!\n");
 739                 wake_up_interruptible(&cl->ev_wait);
 740         }
 741         /* synchronized under device mutex */
 742         if (waitqueue_active(&cl->wait)) {
 743                 cl_dbg(dev, cl, "Waking up ctrl write clients!\n");
 744                 wake_up(&cl->wait);
 745         }
 746 }
 747
 748 /**
 749  * mei_cl_set_disconnected - set disconnected state and clear
 750  *   associated states and resources
 751  *
 752  * @cl: host client
 753  */
 754 void mei_cl_set_disconnected(struct mei_cl *cl)
 755 {
 756         struct mei_device *dev = cl->dev;
 757
 758         if (cl->state == MEI_FILE_DISCONNECTED ||
 759             cl->state == MEI_FILE_INITIALIZING)
 760                 return;
 761
 762         cl->state = MEI_FILE_DISCONNECTED;
 763         mei_io_list_free(&dev->write_list, cl);
 764         mei_io_list_free(&dev->write_waiting_list, cl);
 765         mei_io_list_flush(&dev->ctrl_rd_list, cl);
 766         mei_io_list_flush(&dev->ctrl_wr_list, cl);
 767         mei_cl_wake_all(cl);
 768         cl->rx_flow_ctrl_creds = 0;
 769         cl->tx_flow_ctrl_creds = 0;
 770         cl->timer_count = 0;
 771
 772         if (!cl->me_cl)
 773                 return;
 774
 775         if (!WARN_ON(cl->me_cl->connect_count == 0))
 776                 cl->me_cl->connect_count--;
 777
 778         if (cl->me_cl->connect_count == 0)
 779                 cl->me_cl->tx_flow_ctrl_creds = 0;
 780
 781         mei_me_cl_put(cl->me_cl);
 782         cl->me_cl = NULL;
 783 }
 784
 785 static int mei_cl_set_connecting(struct mei_cl *cl, struct mei_me_client *me_cl)
 786 {
 787         if (!mei_me_cl_get(me_cl))
 788                 return -ENOENT;
 789
 790         /* only one connection is allowed for fixed address clients */
 791         if (me_cl->props.fixed_address) {
 792                 if (me_cl->connect_count) {
 793                         mei_me_cl_put(me_cl);
 794                         return -EBUSY;
 795                 }
 796         }
 797
 798         cl->me_cl = me_cl;
 799         cl->state = MEI_FILE_CONNECTING;
 800         cl->me_cl->connect_count++;
 801
 802         return 0;
 803 }
 804
 805 /*
 806  * mei_cl_send_disconnect - send disconnect request
 807  *
 808  * @cl: host client
 809  * @cb: callback block
 810  *
 811  * Return: 0, OK; otherwise, error.
 812  */
 813 static int mei_cl_send_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb)
 814 {
 815         struct mei_device *dev;
 816         int ret;
 817
 818         dev = cl->dev;
 819
 820         ret = mei_hbm_cl_disconnect_req(dev, cl);
 821         cl->status = ret;
 822         if (ret) {
 823                 cl->state = MEI_FILE_DISCONNECT_REPLY;
 824                 return ret;
 825         }
 826
 827         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 828         cl->timer_count = MEI_CONNECT_TIMEOUT;
 829         mei_schedule_stall_timer(dev);
 830
 831         return 0;
 832 }
 833
 834 /**
 835  * mei_cl_irq_disconnect - processes close related operation from
 836  *      interrupt thread context - send disconnect request
 837  *
 838  * @cl: client
 839  * @cb: callback block.
 840  * @cmpl_list: complete list.
 841  *
 842  * Return: 0, OK; otherwise, error.
 843  */
 844 int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
 845                             struct mei_cl_cb *cmpl_list)
 846 {
 847         struct mei_device *dev = cl->dev;
 848         u32 msg_slots;
 849         int slots;
 850         int ret;
 851
 852         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 853         slots = mei_hbuf_empty_slots(dev);
 854
 855         if (slots < msg_slots)
 856                 return -EMSGSIZE;
 857
 858         ret = mei_cl_send_disconnect(cl, cb);
 859         if (ret)
 860                 list_move_tail(&cb->list, &cmpl_list->list);
 861
 862         return ret;
 863 }
 864
 865 /**
 866  * __mei_cl_disconnect - disconnect host client from the me one
 867  *     internal function runtime pm has to be already acquired
 868  *
 869  * @cl: host client
 870  *
 871  * Return: 0 on success, <0 on failure.
 872  */
 873 static int __mei_cl_disconnect(struct mei_cl *cl)
 874 {
 875         struct mei_device *dev;
 876         struct mei_cl_cb *cb;
 877         int rets;
 878
 879         dev = cl->dev;
 880
 881         cl->state = MEI_FILE_DISCONNECTING;
 882
 883         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT, NULL);
 884         if (!cb) {
 885                 rets = -ENOMEM;
 886                 goto out;
 887         }
 888
 889         if (mei_hbuf_acquire(dev)) {
 890                 rets = mei_cl_send_disconnect(cl, cb);
 891                 if (rets) {
 892                         cl_err(dev, cl, "failed to disconnect.\n");
 893                         goto out;
 894                 }
 895         }
 896
 897         mutex_unlock(&dev->device_lock);
 898         wait_event_timeout(cl->wait,
 899                            cl->state == MEI_FILE_DISCONNECT_REPLY ||
 900                            cl->state == MEI_FILE_DISCONNECTED,
 901                            mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 902         mutex_lock(&dev->device_lock);
 903
 904         rets = cl->status;
 905         if (cl->state != MEI_FILE_DISCONNECT_REPLY &&
 906             cl->state != MEI_FILE_DISCONNECTED) {
 907                 cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
 908                 rets = -ETIME;
 909         }
 910
 911 out:
 912         /* we disconnect also on error */
 913         mei_cl_set_disconnected(cl);
 914         if (!rets)
 915                 cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
 916
 917         mei_io_cb_free(cb);
 918         return rets;
 919 }
 920
 921 /**
 922  * mei_cl_disconnect - disconnect host client from the me one
 923  *
 924  * @cl: host client
 925  *
 926  * Locking: called under "dev->device_lock" lock
 927  *
 928  * Return: 0 on success, <0 on failure.
 929  */
 930 int mei_cl_disconnect(struct mei_cl *cl)
 931 {
 932         struct mei_device *dev;
 933         int rets;
 934
 935         if (WARN_ON(!cl || !cl->dev))
 936                 return -ENODEV;
 937
 938         dev = cl->dev;
 939
 940         cl_dbg(dev, cl, "disconnecting");
 941
 942         if (!mei_cl_is_connected(cl))
 943                 return 0;
 944
 945         if (mei_cl_is_fixed_address(cl)) {
 946                 mei_cl_set_disconnected(cl);
 947                 return 0;
 948         }
 949
 950         rets = pm_runtime_get(dev->dev);
 951         if (rets < 0 && rets != -EINPROGRESS) {
 952                 pm_runtime_put_noidle(dev->dev);
 953                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
 954                 return rets;
 955         }
 956
 957         rets = __mei_cl_disconnect(cl);
 958
 959         cl_dbg(dev, cl, "rpm: autosuspend\n");
 960         pm_runtime_mark_last_busy(dev->dev);
 961         pm_runtime_put_autosuspend(dev->dev);
 962
 963         return rets;
 964 }
 965
 966
 967 /**
 968  * mei_cl_is_other_connecting - checks if other
 969  *    client with the same me client id is connecting
 970  *
 971  * @cl: private data of the file object
 972  *
 973  * Return: true if other client is connected, false - otherwise.
 974  */
 975 static bool mei_cl_is_other_connecting(struct mei_cl *cl)
 976 {
 977         struct mei_device *dev;
 978         struct mei_cl_cb *cb;
 979
 980         dev = cl->dev;
 981
 982         list_for_each_entry(cb, &dev->ctrl_rd_list.list, list) {
 983                 if (cb->fop_type == MEI_FOP_CONNECT &&
 984                     mei_cl_me_id(cl) == mei_cl_me_id(cb->cl))
 985                         return true;
 986         }
 987
 988         return false;
 989 }
 990
 991 /**
 992  * mei_cl_send_connect - send connect request
 993  *
 994  * @cl: host client
 995  * @cb: callback block
 996  *
 997  * Return: 0, OK; otherwise, error.
 998  */
 999 static int mei_cl_send_connect(struct mei_cl *cl, struct mei_cl_cb *cb)
1000 {
1001         struct mei_device *dev;
1002         int ret;
1003
1004         dev = cl->dev;
1005
1006         ret = mei_hbm_cl_connect_req(dev, cl);
1007         cl->status = ret;
1008         if (ret) {
1009                 cl->state = MEI_FILE_DISCONNECT_REPLY;
1010                 return ret;
1011         }
1012
1013         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
1014         cl->timer_count = MEI_CONNECT_TIMEOUT;
1015         mei_schedule_stall_timer(dev);
1016         return 0;
1017 }
1018
1019 /**
1020  * mei_cl_irq_connect - send connect request in irq_thread context
1021  *
1022  * @cl: host client
1023  * @cb: callback block
1024  * @cmpl_list: complete list
1025  *
1026  * Return: 0, OK; otherwise, error.
1027  */
1028 int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
1029                               struct mei_cl_cb *cmpl_list)
1030 {
1031         struct mei_device *dev = cl->dev;
1032         u32 msg_slots;
1033         int slots;
1034         int rets;
1035
1036         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1037         slots = mei_hbuf_empty_slots(dev);
1038
1039         if (mei_cl_is_other_connecting(cl))
1040                 return 0;
1041
1042         if (slots < msg_slots)
1043                 return -EMSGSIZE;
1044
1045         rets = mei_cl_send_connect(cl, cb);
1046         if (rets)
1047                 list_move_tail(&cb->list, &cmpl_list->list);
1048
1049         return rets;
1050 }
1051
1052 /**
1053  * mei_cl_connect - connect host client to the me one
1054  *
1055  * @cl: host client
1056  * @me_cl: me client
1057  * @fp: pointer to file structure
1058  *
1059  * Locking: called under "dev->device_lock" lock
1060  *
1061  * Return: 0 on success, <0 on failure.
1062  */
1063 int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
1064                    const struct file *fp)
1065 {
1066         struct mei_device *dev;
1067         struct mei_cl_cb *cb;
1068         int rets;
1069
1070         if (WARN_ON(!cl || !cl->dev || !me_cl))
1071                 return -ENODEV;
1072
1073         dev = cl->dev;
1074
1075         rets = mei_cl_set_connecting(cl, me_cl);
1076         if (rets)
1077                 return rets;
1078
1079         if (mei_cl_is_fixed_address(cl)) {
1080                 cl->state = MEI_FILE_CONNECTED;
1081                 return 0;
1082         }
1083
1084         rets = pm_runtime_get(dev->dev);
1085         if (rets < 0 && rets != -EINPROGRESS) {
1086                 pm_runtime_put_noidle(dev->dev);
1087                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1088                 goto nortpm;
1089         }
1090
1091         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_CONNECT, fp);
1092         if (!cb) {
1093                 rets = -ENOMEM;
1094                 goto out;
1095         }
1096
1097         /* run hbuf acquire last so we don't have to undo */
1098         if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
1099                 rets = mei_cl_send_connect(cl, cb);
1100                 if (rets)
1101                         goto out;
1102         }
1103
1104         mutex_unlock(&dev->device_lock);
1105         wait_event_timeout(cl->wait,
1106                         (cl->state == MEI_FILE_CONNECTED ||
1107                          cl->state == MEI_FILE_DISCONNECTED ||
1108                          cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
1109                          cl->state == MEI_FILE_DISCONNECT_REPLY),
1110                         mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1111         mutex_lock(&dev->device_lock);
1112
1113         if (!mei_cl_is_connected(cl)) {
1114                 if (cl->state == MEI_FILE_DISCONNECT_REQUIRED) {
1115                         mei_io_list_flush(&dev->ctrl_rd_list, cl);
1116                         mei_io_list_flush(&dev->ctrl_wr_list, cl);
1117                          /* ignore disconnect return valuue;
1118                           * in case of failure reset will be invoked
1119                           */
1120                         __mei_cl_disconnect(cl);
1121                         rets = -EFAULT;
1122                         goto out;
1123                 }
1124
1125                 /* timeout or something went really wrong */
1126                 if (!cl->status)
1127                         cl->status = -EFAULT;
1128         }
1129
1130         rets = cl->status;
1131 out:
1132         cl_dbg(dev, cl, "rpm: autosuspend\n");
1133         pm_runtime_mark_last_busy(dev->dev);
1134         pm_runtime_put_autosuspend(dev->dev);
1135
1136         mei_io_cb_free(cb);
1137
1138 nortpm:
1139         if (!mei_cl_is_connected(cl))
1140                 mei_cl_set_disconnected(cl);
1141
1142         return rets;
1143 }
1144
1145 /**
1146  * mei_cl_alloc_linked - allocate and link host client
1147  *
1148  * @dev: the device structure
1149  *
1150  * Return: cl on success ERR_PTR on failure
1151  */
1152 struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev)
1153 {
1154         struct mei_cl *cl;
1155         int ret;
1156
1157         cl = mei_cl_allocate(dev);
1158         if (!cl) {
1159                 ret = -ENOMEM;
1160                 goto err;
1161         }
1162
1163         ret = mei_cl_link(cl);
1164         if (ret)
1165                 goto err;
1166
1167         return cl;
1168 err:
1169         kfree(cl);
1170         return ERR_PTR(ret);
1171 }
1172
1173 /**
1174  * mei_cl_tx_flow_ctrl_creds - checks flow_control credits for cl.
1175  *
1176  * @cl: host client
1177  *
1178  * Return: 1 if tx_flow_ctrl_creds >0, 0 - otherwise.
1179  */
1180 static int mei_cl_tx_flow_ctrl_creds(struct mei_cl *cl)
1181 {
1182         if (WARN_ON(!cl || !cl->me_cl))
1183                 return -EINVAL;
1184
1185         if (cl->tx_flow_ctrl_creds > 0)
1186                 return 1;
1187
1188         if (mei_cl_is_fixed_address(cl))
1189                 return 1;
1190
1191         if (mei_cl_is_single_recv_buf(cl)) {
1192                 if (cl->me_cl->tx_flow_ctrl_creds > 0)
1193                         return 1;
1194         }
1195         return 0;
1196 }
1197
1198 /**
1199  * mei_cl_tx_flow_ctrl_creds_reduce - reduces transmit flow control credits
1200  *   for a client
1201  *
1202  * @cl: host client
1203  *
1204  * Return:
1205  *      0 on success
1206  *      -EINVAL when ctrl credits are <= 0
1207  */
1208 static int mei_cl_tx_flow_ctrl_creds_reduce(struct mei_cl *cl)
1209 {
1210         if (WARN_ON(!cl || !cl->me_cl))
1211                 return -EINVAL;
1212
1213         if (mei_cl_is_fixed_address(cl))
1214                 return 0;
1215
1216         if (mei_cl_is_single_recv_buf(cl)) {
1217                 if (WARN_ON(cl->me_cl->tx_flow_ctrl_creds <= 0))
1218                         return -EINVAL;
1219                 cl->me_cl->tx_flow_ctrl_creds--;
1220         } else {
1221                 if (WARN_ON(cl->tx_flow_ctrl_creds <= 0))
1222                         return -EINVAL;
1223                 cl->tx_flow_ctrl_creds--;
1224         }
1225         return 0;
1226 }
1227
1228 /**
1229  *  mei_cl_notify_fop2req - convert fop to proper request
1230  *
1231  * @fop: client notification start response command
1232  *
1233  * Return:  MEI_HBM_NOTIFICATION_START/STOP
1234  */
1235 u8 mei_cl_notify_fop2req(enum mei_cb_file_ops fop)
1236 {
1237         if (fop == MEI_FOP_NOTIFY_START)
1238                 return MEI_HBM_NOTIFICATION_START;
1239         else
1240                 return MEI_HBM_NOTIFICATION_STOP;
1241 }
1242
1243 /**
1244  *  mei_cl_notify_req2fop - convert notification request top file operation type
1245  *
1246  * @req: hbm notification request type
1247  *
1248  * Return:  MEI_FOP_NOTIFY_START/STOP
1249  */
1250 enum mei_cb_file_ops mei_cl_notify_req2fop(u8 req)
1251 {
1252         if (req == MEI_HBM_NOTIFICATION_START)
1253                 return MEI_FOP_NOTIFY_START;
1254         else
1255                 return MEI_FOP_NOTIFY_STOP;
1256 }
1257
1258 /**
1259  * mei_cl_irq_notify - send notification request in irq_thread context
1260  *
1261  * @cl: client
1262  * @cb: callback block.
1263  * @cmpl_list: complete list.
1264  *
1265  * Return: 0 on such and error otherwise.
1266  */
1267 int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
1268                       struct mei_cl_cb *cmpl_list)
1269 {
1270         struct mei_device *dev = cl->dev;
1271         u32 msg_slots;
1272         int slots;
1273         int ret;
1274         bool request;
1275
1276         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1277         slots = mei_hbuf_empty_slots(dev);
1278
1279         if (slots < msg_slots)
1280                 return -EMSGSIZE;
1281
1282         request = mei_cl_notify_fop2req(cb->fop_type);
1283         ret = mei_hbm_cl_notify_req(dev, cl, request);
1284         if (ret) {
1285                 cl->status = ret;
1286                 list_move_tail(&cb->list, &cmpl_list->list);
1287                 return ret;
1288         }
1289
1290         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
1291         return 0;
1292 }
1293
1294 /**
1295  * mei_cl_notify_request - send notification stop/start request
1296  *
1297  * @cl: host client
1298  * @fp: associate request with file
1299  * @request: 1 for start or 0 for stop
1300  *
1301  * Locking: called under "dev->device_lock" lock
1302  *
1303  * Return: 0 on such and error otherwise.
1304  */
1305 int mei_cl_notify_request(struct mei_cl *cl,
1306                           const struct file *fp, u8 request)
1307 {
1308         struct mei_device *dev;
1309         struct mei_cl_cb *cb;
1310         enum mei_cb_file_ops fop_type;
1311         int rets;
1312
1313         if (WARN_ON(!cl || !cl->dev))
1314                 return -ENODEV;
1315
1316         dev = cl->dev;
1317
1318         if (!dev->hbm_f_ev_supported) {
1319                 cl_dbg(dev, cl, "notifications not supported\n");
1320                 return -EOPNOTSUPP;
1321         }
1322
1323         rets = pm_runtime_get(dev->dev);
1324         if (rets < 0 && rets != -EINPROGRESS) {
1325                 pm_runtime_put_noidle(dev->dev);
1326                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1327                 return rets;
1328         }
1329
1330         fop_type = mei_cl_notify_req2fop(request);
1331         cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, fop_type, fp);
1332         if (!cb) {
1333                 rets = -ENOMEM;
1334                 goto out;
1335         }
1336
1337         if (mei_hbuf_acquire(dev)) {
1338                 if (mei_hbm_cl_notify_req(dev, cl, request)) {
1339                         rets = -ENODEV;
1340                         goto out;
1341                 }
1342                 list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
1343         }
1344
1345         mutex_unlock(&dev->device_lock);
1346         wait_event_timeout(cl->wait,
1347                            cl->notify_en == request || !mei_cl_is_connected(cl),
1348                            mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1349         mutex_lock(&dev->device_lock);
1350
1351         if (cl->notify_en != request && !cl->status)
1352                 cl->status = -EFAULT;
1353
1354         rets = cl->status;
1355
1356 out:
1357         cl_dbg(dev, cl, "rpm: autosuspend\n");
1358         pm_runtime_mark_last_busy(dev->dev);
1359         pm_runtime_put_autosuspend(dev->dev);
1360
1361         mei_io_cb_free(cb);
1362         return rets;
1363 }
1364
1365 /**
1366  * mei_cl_notify - raise notification
1367  *
1368  * @cl: host client
1369  *
1370  * Locking: called under "dev->device_lock" lock
1371  */
1372 void mei_cl_notify(struct mei_cl *cl)
1373 {
1374         struct mei_device *dev;
1375
1376         if (!cl || !cl->dev)
1377                 return;
1378
1379         dev = cl->dev;
1380
1381         if (!cl->notify_en)
1382                 return;
1383
1384         cl_dbg(dev, cl, "notify event");
1385         cl->notify_ev = true;
1386         if (!mei_cl_bus_notify_event(cl))
1387                 wake_up_interruptible(&cl->ev_wait);
1388
1389         if (cl->ev_async)
1390                 kill_fasync(&cl->ev_async, SIGIO, POLL_PRI);
1391
1392 }
1393
1394 /**
1395  * mei_cl_notify_get - get or wait for notification event
1396  *
1397  * @cl: host client
1398  * @block: this request is blocking
1399  * @notify_ev: true if notification event was received
1400  *
1401  * Locking: called under "dev->device_lock" lock
1402  *
1403  * Return: 0 on such and error otherwise.
1404  */
1405 int mei_cl_notify_get(struct mei_cl *cl, bool block, bool *notify_ev)
1406 {
1407         struct mei_device *dev;
1408         int rets;
1409
1410         *notify_ev = false;
1411
1412         if (WARN_ON(!cl || !cl->dev))
1413                 return -ENODEV;
1414
1415         dev = cl->dev;
1416
1417         if (!mei_cl_is_connected(cl))
1418                 return -ENODEV;
1419
1420         if (cl->notify_ev)
1421                 goto out;
1422
1423         if (!block)
1424                 return -EAGAIN;
1425
1426         mutex_unlock(&dev->device_lock);
1427         rets = wait_event_interruptible(cl->ev_wait, cl->notify_ev);
1428         mutex_lock(&dev->device_lock);
1429
1430         if (rets < 0)
1431                 return rets;
1432
1433 out:
1434         *notify_ev = cl->notify_ev;
1435         cl->notify_ev = false;
1436         return 0;
1437 }
1438
1439 /**
1440  * mei_cl_read_start - the start read client message function.
1441  *
1442  * @cl: host client
1443  * @length: number of bytes to read
1444  * @fp: pointer to file structure
1445  *
1446  * Return: 0 on success, <0 on failure.
1447  */
1448 int mei_cl_read_start(struct mei_cl *cl, size_t length, const struct file *fp)
1449 {
1450         struct mei_device *dev;
1451         struct mei_cl_cb *cb;
1452         int rets;
1453
1454         if (WARN_ON(!cl || !cl->dev))
1455                 return -ENODEV;
1456
1457         dev = cl->dev;
1458
1459         if (!mei_cl_is_connected(cl))
1460                 return -ENODEV;
1461
1462         if (!mei_me_cl_is_active(cl->me_cl)) {
1463                 cl_err(dev, cl, "no such me client\n");
1464                 return  -ENOTTY;
1465         }
1466
1467         if (mei_cl_is_fixed_address(cl) || cl == &dev->iamthif_cl)
1468                 return 0;
1469
1470         /* HW currently supports only one pending read */
1471         if (cl->rx_flow_ctrl_creds)
1472                 return -EBUSY;
1473
1474         cb = mei_cl_enqueue_ctrl_wr_cb(cl, length, MEI_FOP_READ, fp);
1475         if (!cb)
1476                 return -ENOMEM;
1477
1478         rets = pm_runtime_get(dev->dev);
1479         if (rets < 0 && rets != -EINPROGRESS) {
1480                 pm_runtime_put_noidle(dev->dev);
1481                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1482                 goto nortpm;
1483         }
1484
1485         rets = 0;
1486         if (mei_hbuf_acquire(dev)) {
1487                 rets = mei_hbm_cl_flow_control_req(dev, cl);
1488                 if (rets < 0)
1489                         goto out;
1490
1491                 list_move_tail(&cb->list, &cl->rd_pending);
1492         }
1493         cl->rx_flow_ctrl_creds++;
1494
1495 out:
1496         cl_dbg(dev, cl, "rpm: autosuspend\n");
1497         pm_runtime_mark_last_busy(dev->dev);
1498         pm_runtime_put_autosuspend(dev->dev);
1499 nortpm:
1500         if (rets)
1501                 mei_io_cb_free(cb);
1502
1503         return rets;
1504 }
1505
1506 /**
1507  * mei_cl_irq_write - write a message to device
1508  *      from the interrupt thread context
1509  *
1510  * @cl: client
1511  * @cb: callback block.
1512  * @cmpl_list: complete list.
1513  *
1514  * Return: 0, OK; otherwise error.
1515  */
1516 int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
1517                      struct mei_cl_cb *cmpl_list)
1518 {
1519         struct mei_device *dev;
1520         struct mei_msg_data *buf;
1521         struct mei_msg_hdr mei_hdr;
1522         size_t len;
1523         u32 msg_slots;
1524         int slots;
1525         int rets;
1526         bool first_chunk;
1527
1528         if (WARN_ON(!cl || !cl->dev))
1529                 return -ENODEV;
1530
1531         dev = cl->dev;
1532
1533         buf = &cb->buf;
1534
1535         first_chunk = cb->buf_idx == 0;
1536
1537         rets = first_chunk ? mei_cl_tx_flow_ctrl_creds(cl) : 1;
1538         if (rets < 0)
1539                 return rets;
1540
1541         if (rets == 0) {
1542                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1543                 return 0;
1544         }
1545
1546         slots = mei_hbuf_empty_slots(dev);
1547         len = buf->size - cb->buf_idx;
1548         msg_slots = mei_data2slots(len);
1549
1550         mei_hdr.host_addr = mei_cl_host_addr(cl);
1551         mei_hdr.me_addr = mei_cl_me_id(cl);
1552         mei_hdr.reserved = 0;
1553         mei_hdr.internal = cb->internal;
1554
1555         if (slots >= msg_slots) {
1556                 mei_hdr.length = len;
1557                 mei_hdr.msg_complete = 1;
1558         /* Split the message only if we can write the whole host buffer */
1559         } else if (slots == dev->hbuf_depth) {
1560                 msg_slots = slots;
1561                 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
1562                 mei_hdr.length = len;
1563                 mei_hdr.msg_complete = 0;
1564         } else {
1565                 /* wait for next time the host buffer is empty */
1566                 return 0;
1567         }
1568
1569         cl_dbg(dev, cl, "buf: size = %zu idx = %zu\n",
1570                         cb->buf.size, cb->buf_idx);
1571
1572         rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
1573         if (rets) {
1574                 cl->status = rets;
1575                 list_move_tail(&cb->list, &cmpl_list->list);
1576                 return rets;
1577         }
1578
1579         cl->status = 0;
1580         cl->writing_state = MEI_WRITING;
1581         cb->buf_idx += mei_hdr.length;
1582         cb->completed = mei_hdr.msg_complete == 1;
1583
1584         if (first_chunk) {
1585                 if (mei_cl_tx_flow_ctrl_creds_reduce(cl))
1586                         return -EIO;
1587         }
1588
1589         if (mei_hdr.msg_complete)
1590                 list_move_tail(&cb->list, &dev->write_waiting_list.list);
1591
1592         return 0;
1593 }
1594
1595 /**
1596  * mei_cl_write - submit a write cb to mei device
1597  *      assumes device_lock is locked
1598  *
1599  * @cl: host client
1600  * @cb: write callback with filled data
1601  * @blocking: block until completed
1602  *
1603  * Return: number of bytes sent on success, <0 on failure.
1604  */
1605 int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking)
1606 {
1607         struct mei_device *dev;
1608         struct mei_msg_data *buf;
1609         struct mei_msg_hdr mei_hdr;
1610         int size;
1611         int rets;
1612
1613
1614         if (WARN_ON(!cl || !cl->dev))
1615                 return -ENODEV;
1616
1617         if (WARN_ON(!cb))
1618                 return -EINVAL;
1619
1620         dev = cl->dev;
1621
1622         buf = &cb->buf;
1623         size = buf->size;
1624
1625         cl_dbg(dev, cl, "size=%d\n", size);
1626
1627         rets = pm_runtime_get(dev->dev);
1628         if (rets < 0 && rets != -EINPROGRESS) {
1629                 pm_runtime_put_noidle(dev->dev);
1630                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1631                 goto free;
1632         }
1633
1634         cb->buf_idx = 0;
1635         cl->writing_state = MEI_IDLE;
1636
1637         mei_hdr.host_addr = mei_cl_host_addr(cl);
1638         mei_hdr.me_addr = mei_cl_me_id(cl);
1639         mei_hdr.reserved = 0;
1640         mei_hdr.msg_complete = 0;
1641         mei_hdr.internal = cb->internal;
1642
1643         rets = mei_cl_tx_flow_ctrl_creds(cl);
1644         if (rets < 0)
1645                 goto err;
1646
1647         if (rets == 0) {
1648                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1649                 rets = size;
1650                 goto out;
1651         }
1652         if (!mei_hbuf_acquire(dev)) {
1653                 cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
1654                 rets = size;
1655                 goto out;
1656         }
1657
1658         /* Check for a maximum length */
1659         if (size > mei_hbuf_max_len(dev)) {
1660                 mei_hdr.length = mei_hbuf_max_len(dev);
1661                 mei_hdr.msg_complete = 0;
1662         } else {
1663                 mei_hdr.length = size;
1664                 mei_hdr.msg_complete = 1;
1665         }
1666
1667         rets = mei_write_message(dev, &mei_hdr, buf->data);
1668         if (rets)
1669                 goto err;
1670
1671         rets = mei_cl_tx_flow_ctrl_creds_reduce(cl);
1672         if (rets)
1673                 goto err;
1674
1675         cl->writing_state = MEI_WRITING;
1676         cb->buf_idx = mei_hdr.length;
1677         cb->completed = mei_hdr.msg_complete == 1;
1678
1679 out:
1680         if (mei_hdr.msg_complete)
1681                 list_add_tail(&cb->list, &dev->write_waiting_list.list);
1682         else
1683                 list_add_tail(&cb->list, &dev->write_list.list);
1684
1685         cb = NULL;
1686         if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
1687
1688                 mutex_unlock(&dev->device_lock);
1689                 rets = wait_event_interruptible(cl->tx_wait,
1690                                 cl->writing_state == MEI_WRITE_COMPLETE ||
1691                                 (!mei_cl_is_connected(cl)));
1692                 mutex_lock(&dev->device_lock);
1693                 /* wait_event_interruptible returns -ERESTARTSYS */
1694                 if (rets) {
1695                         if (signal_pending(current))
1696                                 rets = -EINTR;
1697                         goto err;
1698                 }
1699                 if (cl->writing_state != MEI_WRITE_COMPLETE) {
1700                         rets = -EFAULT;
1701                         goto err;
1702                 }
1703         }
1704
1705         rets = size;
1706 err:
1707         cl_dbg(dev, cl, "rpm: autosuspend\n");
1708         pm_runtime_mark_last_busy(dev->dev);
1709         pm_runtime_put_autosuspend(dev->dev);
1710 free:
1711         mei_io_cb_free(cb);
1712
1713         return rets;
1714 }
1715
1716
1717 /**
1718  * mei_cl_complete - processes completed operation for a client
1719  *
1720  * @cl: private data of the file object.
1721  * @cb: callback block.
1722  */
1723 void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
1724 {
1725         struct mei_device *dev = cl->dev;
1726
1727         switch (cb->fop_type) {
1728         case MEI_FOP_WRITE:
1729                 mei_io_cb_free(cb);
1730                 cl->writing_state = MEI_WRITE_COMPLETE;
1731                 if (waitqueue_active(&cl->tx_wait)) {
1732                         wake_up_interruptible(&cl->tx_wait);
1733                 } else {
1734                         pm_runtime_mark_last_busy(dev->dev);
1735                         pm_request_autosuspend(dev->dev);
1736                 }
1737                 break;
1738
1739         case MEI_FOP_READ:
1740                 list_add_tail(&cb->list, &cl->rd_completed);
1741                 if (!mei_cl_is_fixed_address(cl) &&
1742                     !WARN_ON(!cl->rx_flow_ctrl_creds))
1743                         cl->rx_flow_ctrl_creds--;
1744                 if (!mei_cl_bus_rx_event(cl))
1745                         wake_up_interruptible(&cl->rx_wait);
1746                 break;
1747
1748         case MEI_FOP_CONNECT:
1749         case MEI_FOP_DISCONNECT:
1750         case MEI_FOP_NOTIFY_STOP:
1751         case MEI_FOP_NOTIFY_START:
1752                 if (waitqueue_active(&cl->wait))
1753                         wake_up(&cl->wait);
1754
1755                 break;
1756         case MEI_FOP_DISCONNECT_RSP:
1757                 mei_io_cb_free(cb);
1758                 mei_cl_set_disconnected(cl);
1759                 break;
1760         default:
1761                 BUG_ON(0);
1762         }
1763 }
1764
1765
1766 /**
1767  * mei_cl_all_disconnect - disconnect forcefully all connected clients
1768  *
1769  * @dev: mei device
1770  */
1771 void mei_cl_all_disconnect(struct mei_device *dev)
1772 {
1773         struct mei_cl *cl;
1774
1775         list_for_each_entry(cl, &dev->file_list, link)
1776                 mei_cl_set_disconnected(cl);
1777 }