drivers/misc/mei/client.c

   1 /*
   2  *
   3  * Intel Management Engine Interface (Intel MEI) Linux driver
   4  * Copyright (c) 2003-2012, Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  */
  16
  17 #include <linux/sched.h>
  18 #include <linux/wait.h>
  19 #include <linux/delay.h>
  20 #include <linux/slab.h>
  21 #include <linux/pm_runtime.h>
  22
  23 #include <linux/mei.h>
  24
  25 #include "mei_dev.h"
  26 #include "hbm.h"
  27 #include "client.h"
  28
  29 /**
  30  * mei_me_cl_init - initialize me client
  31  *
  32  * @me_cl: me client
  33  */
  34 void mei_me_cl_init(struct mei_me_client *me_cl)
  35 {
  36         INIT_LIST_HEAD(&me_cl->list);
  37         kref_init(&me_cl->refcnt);
  38 }
  39
  40 /**
  41  * mei_me_cl_get - increases me client refcount
  42  *
  43  * @me_cl: me client
  44  *
  45  * Locking: called under "dev->device_lock" lock
  46  *
  47  * Return: me client or NULL
  48  */
  49 struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl)
  50 {
  51         if (me_cl && kref_get_unless_zero(&me_cl->refcnt))
  52                 return me_cl;
  53
  54         return NULL;
  55 }
  56
  57 /**
  58  * mei_me_cl_release - free me client
  59  *
  60  * Locking: called under "dev->device_lock" lock
  61  *
  62  * @ref: me_client refcount
  63  */
  64 static void mei_me_cl_release(struct kref *ref)
  65 {
  66         struct mei_me_client *me_cl =
  67                 container_of(ref, struct mei_me_client, refcnt);
  68
  69         kfree(me_cl);
  70 }
  71
  72 /**
  73  * mei_me_cl_put - decrease me client refcount and free client if necessary
  74  *
  75  * Locking: called under "dev->device_lock" lock
  76  *
  77  * @me_cl: me client
  78  */
  79 void mei_me_cl_put(struct mei_me_client *me_cl)
  80 {
  81         if (me_cl)
  82                 kref_put(&me_cl->refcnt, mei_me_cl_release);
  83 }
  84
  85 /**
  86  * __mei_me_cl_del  - delete me client from the list and decrease
  87  *     reference counter
  88  *
  89  * @dev: mei device
  90  * @me_cl: me client
  91  *
  92  * Locking: dev->me_clients_rwsem
  93  */
  94 static void __mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
  95 {
  96         if (!me_cl)
  97                 return;
  98
  99         list_del_init(&me_cl->list);
 100         mei_me_cl_put(me_cl);
 101 }
 102
 103 /**
 104  * mei_me_cl_del - delete me client from the list and decrease
 105  *     reference counter
 106  *
 107  * @dev: mei device
 108  * @me_cl: me client
 109  */
 110 void mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
 111 {
 112         down_write(&dev->me_clients_rwsem);
 113         __mei_me_cl_del(dev, me_cl);
 114         up_write(&dev->me_clients_rwsem);
 115 }
 116
 117 /**
 118  * mei_me_cl_add - add me client to the list
 119  *
 120  * @dev: mei device
 121  * @me_cl: me client
 122  */
 123 void mei_me_cl_add(struct mei_device *dev, struct mei_me_client *me_cl)
 124 {
 125         down_write(&dev->me_clients_rwsem);
 126         list_add(&me_cl->list, &dev->me_clients);
 127         up_write(&dev->me_clients_rwsem);
 128 }
 129
 130 /**
 131  * __mei_me_cl_by_uuid - locate me client by uuid
 132  *      increases ref count
 133  *
 134  * @dev: mei device
 135  * @uuid: me client uuid
 136  *
 137  * Return: me client or NULL if not found
 138  *
 139  * Locking: dev->me_clients_rwsem
 140  */
 141 static struct mei_me_client *__mei_me_cl_by_uuid(struct mei_device *dev,
 142                                         const uuid_le *uuid)
 143 {
 144         struct mei_me_client *me_cl;
 145         const uuid_le *pn;
 146
 147         WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
 148
 149         list_for_each_entry(me_cl, &dev->me_clients, list) {
 150                 pn = &me_cl->props.protocol_name;
 151                 if (uuid_le_cmp(*uuid, *pn) == 0)
 152                         return mei_me_cl_get(me_cl);
 153         }
 154
 155         return NULL;
 156 }
 157
 158 /**
 159  * mei_me_cl_by_uuid - locate me client by uuid
 160  *      increases ref count
 161  *
 162  * @dev: mei device
 163  * @uuid: me client uuid
 164  *
 165  * Return: me client or NULL if not found
 166  *
 167  * Locking: dev->me_clients_rwsem
 168  */
 169 struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev,
 170                                         const uuid_le *uuid)
 171 {
 172         struct mei_me_client *me_cl;
 173
 174         down_read(&dev->me_clients_rwsem);
 175         me_cl = __mei_me_cl_by_uuid(dev, uuid);
 176         up_read(&dev->me_clients_rwsem);
 177
 178         return me_cl;
 179 }
 180
 181 /**
 182  * mei_me_cl_by_id - locate me client by client id
 183  *      increases ref count
 184  *
 185  * @dev: the device structure
 186  * @client_id: me client id
 187  *
 188  * Return: me client or NULL if not found
 189  *
 190  * Locking: dev->me_clients_rwsem
 191  */
 192 struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
 193 {
 194
 195         struct mei_me_client *__me_cl, *me_cl = NULL;
 196
 197         down_read(&dev->me_clients_rwsem);
 198         list_for_each_entry(__me_cl, &dev->me_clients, list) {
 199                 if (__me_cl->client_id == client_id) {
 200                         me_cl = mei_me_cl_get(__me_cl);
 201                         break;
 202                 }
 203         }
 204         up_read(&dev->me_clients_rwsem);
 205
 206         return me_cl;
 207 }
 208
 209 /**
 210  * __mei_me_cl_by_uuid_id - locate me client by client id and uuid
 211  *      increases ref count
 212  *
 213  * @dev: the device structure
 214  * @uuid: me client uuid
 215  * @client_id: me client id
 216  *
 217  * Return: me client or null if not found
 218  *
 219  * Locking: dev->me_clients_rwsem
 220  */
 221 static struct mei_me_client *__mei_me_cl_by_uuid_id(struct mei_device *dev,
 222                                            const uuid_le *uuid, u8 client_id)
 223 {
 224         struct mei_me_client *me_cl;
 225         const uuid_le *pn;
 226
 227         WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
 228
 229         list_for_each_entry(me_cl, &dev->me_clients, list) {
 230                 pn = &me_cl->props.protocol_name;
 231                 if (uuid_le_cmp(*uuid, *pn) == 0 &&
 232                     me_cl->client_id == client_id)
 233                         return mei_me_cl_get(me_cl);
 234         }
 235
 236         return NULL;
 237 }
 238
 239
 240 /**
 241  * mei_me_cl_by_uuid_id - locate me client by client id and uuid
 242  *      increases ref count
 243  *
 244  * @dev: the device structure
 245  * @uuid: me client uuid
 246  * @client_id: me client id
 247  *
 248  * Return: me client or null if not found
 249  */
 250 struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
 251                                            const uuid_le *uuid, u8 client_id)
 252 {
 253         struct mei_me_client *me_cl;
 254
 255         down_read(&dev->me_clients_rwsem);
 256         me_cl = __mei_me_cl_by_uuid_id(dev, uuid, client_id);
 257         up_read(&dev->me_clients_rwsem);
 258
 259         return me_cl;
 260 }
 261
 262 /**
 263  * mei_me_cl_rm_by_uuid - remove all me clients matching uuid
 264  *
 265  * @dev: the device structure
 266  * @uuid: me client uuid
 267  *
 268  * Locking: called under "dev->device_lock" lock
 269  */
 270 void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid)
 271 {
 272         struct mei_me_client *me_cl;
 273
 274         dev_dbg(dev->dev, "remove %pUl\n", uuid);
 275
 276         down_write(&dev->me_clients_rwsem);
 277         me_cl = __mei_me_cl_by_uuid(dev, uuid);
 278         __mei_me_cl_del(dev, me_cl);
 279         up_write(&dev->me_clients_rwsem);
 280 }
 281
 282 /**
 283  * mei_me_cl_rm_by_uuid_id - remove all me clients matching client id
 284  *
 285  * @dev: the device structure
 286  * @uuid: me client uuid
 287  * @id: me client id
 288  *
 289  * Locking: called under "dev->device_lock" lock
 290  */
 291 void mei_me_cl_rm_by_uuid_id(struct mei_device *dev, const uuid_le *uuid, u8 id)
 292 {
 293         struct mei_me_client *me_cl;
 294
 295         dev_dbg(dev->dev, "remove %pUl %d\n", uuid, id);
 296
 297         down_write(&dev->me_clients_rwsem);
 298         me_cl = __mei_me_cl_by_uuid_id(dev, uuid, id);
 299         __mei_me_cl_del(dev, me_cl);
 300         up_write(&dev->me_clients_rwsem);
 301 }
 302
 303 /**
 304  * mei_me_cl_rm_all - remove all me clients
 305  *
 306  * @dev: the device structure
 307  *
 308  * Locking: called under "dev->device_lock" lock
 309  */
 310 void mei_me_cl_rm_all(struct mei_device *dev)
 311 {
 312         struct mei_me_client *me_cl, *next;
 313
 314         down_write(&dev->me_clients_rwsem);
 315         list_for_each_entry_safe(me_cl, next, &dev->me_clients, list)
 316                 __mei_me_cl_del(dev, me_cl);
 317         up_write(&dev->me_clients_rwsem);
 318 }
 319
 320 /**
 321  * mei_cl_cmp_id - tells if the clients are the same
 322  *
 323  * @cl1: host client 1
 324  * @cl2: host client 2
 325  *
 326  * Return: true  - if the clients has same host and me ids
 327  *         false - otherwise
 328  */
 329 static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
 330                                 const struct mei_cl *cl2)
 331 {
 332         return cl1 && cl2 &&
 333                 (cl1->host_client_id == cl2->host_client_id) &&
 334                 (mei_cl_me_id(cl1) == mei_cl_me_id(cl2));
 335 }
 336
 337 /**
 338  * mei_io_cb_free - free mei_cb_private related memory
 339  *
 340  * @cb: mei callback struct
 341  */
 342 void mei_io_cb_free(struct mei_cl_cb *cb)
 343 {
 344         if (cb == NULL)
 345                 return;
 346
 347         list_del(&cb->list);
 348         kfree(cb->buf.data);
 349         kfree(cb);
 350 }
 351
 352 /**
 353  * mei_io_cb_init - allocate and initialize io callback
 354  *
 355  * @cl: mei client
 356  * @type: operation type
 357  * @fp: pointer to file structure
 358  *
 359  * Return: mei_cl_cb pointer or NULL;
 360  */
 361 struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, enum mei_cb_file_ops type,
 362                                  const struct file *fp)
 363 {
 364         struct mei_cl_cb *cb;
 365
 366         cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
 367         if (!cb)
 368                 return NULL;
 369
 370         INIT_LIST_HEAD(&cb->list);
 371         cb->fp = fp;
 372         cb->cl = cl;
 373         cb->buf_idx = 0;
 374         cb->fop_type = type;
 375         return cb;
 376 }
 377
 378 /**
 379  * __mei_io_list_flush - removes and frees cbs belonging to cl.
 380  *
 381  * @list:  an instance of our list structure
 382  * @cl:    host client, can be NULL for flushing the whole list
 383  * @free:  whether to free the cbs
 384  */
 385 static void __mei_io_list_flush(struct mei_cl_cb *list,
 386                                 struct mei_cl *cl, bool free)
 387 {
 388         struct mei_cl_cb *cb, *next;
 389
 390         /* enable removing everything if no cl is specified */
 391         list_for_each_entry_safe(cb, next, &list->list, list) {
 392                 if (!cl || mei_cl_cmp_id(cl, cb->cl)) {
 393                         list_del_init(&cb->list);
 394                         if (free)
 395                                 mei_io_cb_free(cb);
 396                 }
 397         }
 398 }
 399
 400 /**
 401  * mei_io_list_flush - removes list entry belonging to cl.
 402  *
 403  * @list:  An instance of our list structure
 404  * @cl: host client
 405  */
 406 void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl)
 407 {
 408         __mei_io_list_flush(list, cl, false);
 409 }
 410
 411 /**
 412  * mei_io_list_free - removes cb belonging to cl and free them
 413  *
 414  * @list:  An instance of our list structure
 415  * @cl: host client
 416  */
 417 static inline void mei_io_list_free(struct mei_cl_cb *list, struct mei_cl *cl)
 418 {
 419         __mei_io_list_flush(list, cl, true);
 420 }
 421
 422 /**
 423  * mei_io_cb_alloc_buf - allocate callback buffer
 424  *
 425  * @cb: io callback structure
 426  * @length: size of the buffer
 427  *
 428  * Return: 0 on success
 429  *         -EINVAL if cb is NULL
 430  *         -ENOMEM if allocation failed
 431  */
 432 int mei_io_cb_alloc_buf(struct mei_cl_cb *cb, size_t length)
 433 {
 434         if (!cb)
 435                 return -EINVAL;
 436
 437         if (length == 0)
 438                 return 0;
 439
 440         cb->buf.data = kmalloc(length, GFP_KERNEL);
 441         if (!cb->buf.data)
 442                 return -ENOMEM;
 443         cb->buf.size = length;
 444         return 0;
 445 }
 446
 447 /**
 448  * mei_cl_alloc_cb - a convenient wrapper for allocating read cb
 449  *
 450  * @cl: host client
 451  * @length: size of the buffer
 452  * @type: operation type
 453  * @fp: associated file pointer (might be NULL)
 454  *
 455  * Return: cb on success and NULL on failure
 456  */
 457 struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
 458                                   enum mei_cb_file_ops type,
 459                                   const struct file *fp)
 460 {
 461         struct mei_cl_cb *cb;
 462
 463         cb = mei_io_cb_init(cl, type, fp);
 464         if (!cb)
 465                 return NULL;
 466
 467         if (mei_io_cb_alloc_buf(cb, length)) {
 468                 mei_io_cb_free(cb);
 469                 return NULL;
 470         }
 471
 472         return cb;
 473 }
 474
 475 /**
 476  * mei_cl_read_cb - find this cl's callback in the read list
 477  *     for a specific file
 478  *
 479  * @cl: host client
 480  * @fp: file pointer (matching cb file object), may be NULL
 481  *
 482  * Return: cb on success, NULL if cb is not found
 483  */
 484 struct mei_cl_cb *mei_cl_read_cb(const struct mei_cl *cl, const struct file *fp)
 485 {
 486         struct mei_cl_cb *cb;
 487
 488         list_for_each_entry(cb, &cl->rd_completed, list)
 489                 if (!fp || fp == cb->fp)
 490                         return cb;
 491
 492         return NULL;
 493 }
 494
 495 /**
 496  * mei_cl_read_cb_flush - free client's read pending and completed cbs
 497  *   for a specific file
 498  *
 499  * @cl: host client
 500  * @fp: file pointer (matching cb file object), may be NULL
 501  */
 502 void mei_cl_read_cb_flush(const struct mei_cl *cl, const struct file *fp)
 503 {
 504         struct mei_cl_cb *cb, *next;
 505
 506         list_for_each_entry_safe(cb, next, &cl->rd_completed, list)
 507                 if (!fp || fp == cb->fp)
 508                         mei_io_cb_free(cb);
 509
 510
 511         list_for_each_entry_safe(cb, next, &cl->rd_pending, list)
 512                 if (!fp || fp == cb->fp)
 513                         mei_io_cb_free(cb);
 514 }
 515
 516 /**
 517  * mei_cl_flush_queues - flushes queue lists belonging to cl.
 518  *
 519  * @cl: host client
 520  * @fp: file pointer (matching cb file object), may be NULL
 521  *
 522  * Return: 0 on success, -EINVAL if cl or cl->dev is NULL.
 523  */
 524 int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp)
 525 {
 526         struct mei_device *dev;
 527
 528         if (WARN_ON(!cl || !cl->dev))
 529                 return -EINVAL;
 530
 531         dev = cl->dev;
 532
 533         cl_dbg(dev, cl, "remove list entry belonging to cl\n");
 534         mei_io_list_free(&cl->dev->write_list, cl);
 535         mei_io_list_free(&cl->dev->write_waiting_list, cl);
 536         mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
 537         mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
 538         mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
 539
 540         mei_cl_read_cb_flush(cl, fp);
 541
 542         return 0;
 543 }
 544
 545
 546 /**
 547  * mei_cl_init - initializes cl.
 548  *
 549  * @cl: host client to be initialized
 550  * @dev: mei device
 551  */
 552 void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
 553 {
 554         memset(cl, 0, sizeof(struct mei_cl));
 555         init_waitqueue_head(&cl->wait);
 556         init_waitqueue_head(&cl->rx_wait);
 557         init_waitqueue_head(&cl->tx_wait);
 558         init_waitqueue_head(&cl->ev_wait);
 559         INIT_LIST_HEAD(&cl->rd_completed);
 560         INIT_LIST_HEAD(&cl->rd_pending);
 561         INIT_LIST_HEAD(&cl->link);
 562         cl->writing_state = MEI_IDLE;
 563         cl->state = MEI_FILE_INITIALIZING;
 564         cl->dev = dev;
 565 }
 566
 567 /**
 568  * mei_cl_allocate - allocates cl  structure and sets it up.
 569  *
 570  * @dev: mei device
 571  * Return:  The allocated file or NULL on failure
 572  */
 573 struct mei_cl *mei_cl_allocate(struct mei_device *dev)
 574 {
 575         struct mei_cl *cl;
 576
 577         cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
 578         if (!cl)
 579                 return NULL;
 580
 581         mei_cl_init(cl, dev);
 582
 583         return cl;
 584 }
 585
 586 /**
 587  * mei_cl_link - allocate host id in the host map
 588  *
 589  * @cl: host client
 590  *
 591  * Return: 0 on success
 592  *      -EINVAL on incorrect values
 593  *      -EMFILE if open count exceeded.
 594  */
 595 int mei_cl_link(struct mei_cl *cl)
 596 {
 597         struct mei_device *dev;
 598         long open_handle_count;
 599         int id;
 600
 601         if (WARN_ON(!cl || !cl->dev))
 602                 return -EINVAL;
 603
 604         dev = cl->dev;
 605
 606         id = find_first_zero_bit(dev->host_clients_map, MEI_CLIENTS_MAX);
 607         if (id >= MEI_CLIENTS_MAX) {
 608                 dev_err(dev->dev, "id exceeded %d", MEI_CLIENTS_MAX);
 609                 return -EMFILE;
 610         }
 611
 612         open_handle_count = dev->open_handle_count + dev->iamthif_open_count;
 613         if (open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
 614                 dev_err(dev->dev, "open_handle_count exceeded %d",
 615                         MEI_MAX_OPEN_HANDLE_COUNT);
 616                 return -EMFILE;
 617         }
 618
 619         dev->open_handle_count++;
 620
 621         cl->host_client_id = id;
 622         list_add_tail(&cl->link, &dev->file_list);
 623
 624         set_bit(id, dev->host_clients_map);
 625
 626         cl->state = MEI_FILE_INITIALIZING;
 627
 628         cl_dbg(dev, cl, "link cl\n");
 629         return 0;
 630 }
 631
 632 /**
 633  * mei_cl_unlink - remove host client from the list
 634  *
 635  * @cl: host client
 636  *
 637  * Return: always 0
 638  */
 639 int mei_cl_unlink(struct mei_cl *cl)
 640 {
 641         struct mei_device *dev;
 642
 643         /* don't shout on error exit path */
 644         if (!cl)
 645                 return 0;
 646
 647         /* amthif might not be initialized */
 648         if (!cl->dev)
 649                 return 0;
 650
 651         dev = cl->dev;
 652
 653         cl_dbg(dev, cl, "unlink client");
 654
 655         if (dev->open_handle_count > 0)
 656                 dev->open_handle_count--;
 657
 658         /* never clear the 0 bit */
 659         if (cl->host_client_id)
 660                 clear_bit(cl->host_client_id, dev->host_clients_map);
 661
 662         list_del_init(&cl->link);
 663
 664         cl->state = MEI_FILE_INITIALIZING;
 665
 666         return 0;
 667 }
 668
 669 void mei_host_client_init(struct mei_device *dev)
 670 {
 671         dev->dev_state = MEI_DEV_ENABLED;
 672         dev->reset_count = 0;
 673
 674         schedule_work(&dev->bus_rescan_work);
 675
 676         pm_runtime_mark_last_busy(dev->dev);
 677         dev_dbg(dev->dev, "rpm: autosuspend\n");
 678         pm_runtime_autosuspend(dev->dev);
 679 }
 680
 681 /**
 682  * mei_hbuf_acquire - try to acquire host buffer
 683  *
 684  * @dev: the device structure
 685  * Return: true if host buffer was acquired
 686  */
 687 bool mei_hbuf_acquire(struct mei_device *dev)
 688 {
 689         if (mei_pg_state(dev) == MEI_PG_ON ||
 690             mei_pg_in_transition(dev)) {
 691                 dev_dbg(dev->dev, "device is in pg\n");
 692                 return false;
 693         }
 694
 695         if (!dev->hbuf_is_ready) {
 696                 dev_dbg(dev->dev, "hbuf is not ready\n");
 697                 return false;
 698         }
 699
 700         dev->hbuf_is_ready = false;
 701
 702         return true;
 703 }
 704
 705 /**
 706  * mei_cl_wake_all - wake up readers, writers and event waiters so
 707  *                 they can be interrupted
 708  *
 709  * @cl: host client
 710  */
 711 static void mei_cl_wake_all(struct mei_cl *cl)
 712 {
 713         struct mei_device *dev = cl->dev;
 714
 715         /* synchronized under device mutex */
 716         if (waitqueue_active(&cl->rx_wait)) {
 717                 cl_dbg(dev, cl, "Waking up reading client!\n");
 718                 wake_up_interruptible(&cl->rx_wait);
 719         }
 720         /* synchronized under device mutex */
 721         if (waitqueue_active(&cl->tx_wait)) {
 722                 cl_dbg(dev, cl, "Waking up writing client!\n");
 723                 wake_up_interruptible(&cl->tx_wait);
 724         }
 725         /* synchronized under device mutex */
 726         if (waitqueue_active(&cl->ev_wait)) {
 727                 cl_dbg(dev, cl, "Waking up waiting for event clients!\n");
 728                 wake_up_interruptible(&cl->ev_wait);
 729         }
 730         /* synchronized under device mutex */
 731         if (waitqueue_active(&cl->wait)) {
 732                 cl_dbg(dev, cl, "Waking up ctrl write clients!\n");
 733                 wake_up_interruptible(&cl->wait);
 734         }
 735 }
 736
 737 /**
 738  * mei_cl_set_disconnected - set disconnected state and clear
 739  *   associated states and resources
 740  *
 741  * @cl: host client
 742  */
 743 void mei_cl_set_disconnected(struct mei_cl *cl)
 744 {
 745         struct mei_device *dev = cl->dev;
 746
 747         if (cl->state == MEI_FILE_DISCONNECTED ||
 748             cl->state == MEI_FILE_INITIALIZING)
 749                 return;
 750
 751         cl->state = MEI_FILE_DISCONNECTED;
 752         mei_io_list_free(&dev->write_list, cl);
 753         mei_io_list_free(&dev->write_waiting_list, cl);
 754         mei_io_list_flush(&dev->ctrl_rd_list, cl);
 755         mei_io_list_flush(&dev->ctrl_wr_list, cl);
 756         mei_cl_wake_all(cl);
 757         cl->mei_flow_ctrl_creds = 0;
 758         cl->timer_count = 0;
 759
 760         if (!cl->me_cl)
 761                 return;
 762
 763         if (!WARN_ON(cl->me_cl->connect_count == 0))
 764                 cl->me_cl->connect_count--;
 765
 766         if (cl->me_cl->connect_count == 0)
 767                 cl->me_cl->mei_flow_ctrl_creds = 0;
 768
 769         mei_me_cl_put(cl->me_cl);
 770         cl->me_cl = NULL;
 771 }
 772
 773 static int mei_cl_set_connecting(struct mei_cl *cl, struct mei_me_client *me_cl)
 774 {
 775         if (!mei_me_cl_get(me_cl))
 776                 return -ENOENT;
 777
 778         /* only one connection is allowed for fixed address clients */
 779         if (me_cl->props.fixed_address) {
 780                 if (me_cl->connect_count) {
 781                         mei_me_cl_put(me_cl);
 782                         return -EBUSY;
 783                 }
 784         }
 785
 786         cl->me_cl = me_cl;
 787         cl->state = MEI_FILE_CONNECTING;
 788         cl->me_cl->connect_count++;
 789
 790         return 0;
 791 }
 792
 793 /*
 794  * mei_cl_send_disconnect - send disconnect request
 795  *
 796  * @cl: host client
 797  * @cb: callback block
 798  *
 799  * Return: 0, OK; otherwise, error.
 800  */
 801 static int mei_cl_send_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb)
 802 {
 803         struct mei_device *dev;
 804         int ret;
 805
 806         dev = cl->dev;
 807
 808         ret = mei_hbm_cl_disconnect_req(dev, cl);
 809         cl->status = ret;
 810         if (ret) {
 811                 cl->state = MEI_FILE_DISCONNECT_REPLY;
 812                 return ret;
 813         }
 814
 815         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 816         cl->timer_count = MEI_CONNECT_TIMEOUT;
 817
 818         return 0;
 819 }
 820
 821 /**
 822  * mei_cl_irq_disconnect - processes close related operation from
 823  *      interrupt thread context - send disconnect request
 824  *
 825  * @cl: client
 826  * @cb: callback block.
 827  * @cmpl_list: complete list.
 828  *
 829  * Return: 0, OK; otherwise, error.
 830  */
 831 int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
 832                             struct mei_cl_cb *cmpl_list)
 833 {
 834         struct mei_device *dev = cl->dev;
 835         u32 msg_slots;
 836         int slots;
 837         int ret;
 838
 839         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 840         slots = mei_hbuf_empty_slots(dev);
 841
 842         if (slots < msg_slots)
 843                 return -EMSGSIZE;
 844
 845         ret = mei_cl_send_disconnect(cl, cb);
 846         if (ret)
 847                 list_move_tail(&cb->list, &cmpl_list->list);
 848
 849         return ret;
 850 }
 851
 852 /**
 853  * __mei_cl_disconnect - disconnect host client from the me one
 854  *     internal function runtime pm has to be already acquired
 855  *
 856  * @cl: host client
 857  *
 858  * Return: 0 on success, <0 on failure.
 859  */
 860 static int __mei_cl_disconnect(struct mei_cl *cl)
 861 {
 862         struct mei_device *dev;
 863         struct mei_cl_cb *cb;
 864         int rets;
 865
 866         dev = cl->dev;
 867
 868         cl->state = MEI_FILE_DISCONNECTING;
 869
 870         cb = mei_io_cb_init(cl, MEI_FOP_DISCONNECT, NULL);
 871         rets = cb ? 0 : -ENOMEM;
 872         if (rets)
 873                 goto out;
 874
 875         cl_dbg(dev, cl, "add disconnect cb to control write list\n");
 876         list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
 877
 878         if (mei_hbuf_acquire(dev)) {
 879                 rets = mei_cl_send_disconnect(cl, cb);
 880                 if (rets) {
 881                         cl_err(dev, cl, "failed to disconnect.\n");
 882                         goto out;
 883                 }
 884         }
 885
 886         mutex_unlock(&dev->device_lock);
 887         wait_event_timeout(cl->wait,
 888                            cl->state == MEI_FILE_DISCONNECT_REPLY ||
 889                            cl->state == MEI_FILE_DISCONNECTED,
 890                            mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 891         mutex_lock(&dev->device_lock);
 892
 893         rets = cl->status;
 894         if (cl->state != MEI_FILE_DISCONNECT_REPLY &&
 895             cl->state != MEI_FILE_DISCONNECTED) {
 896                 cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
 897                 rets = -ETIME;
 898         }
 899
 900 out:
 901         /* we disconnect also on error */
 902         mei_cl_set_disconnected(cl);
 903         if (!rets)
 904                 cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
 905
 906         mei_io_cb_free(cb);
 907         return rets;
 908 }
 909
 910 /**
 911  * mei_cl_disconnect - disconnect host client from the me one
 912  *
 913  * @cl: host client
 914  *
 915  * Locking: called under "dev->device_lock" lock
 916  *
 917  * Return: 0 on success, <0 on failure.
 918  */
 919 int mei_cl_disconnect(struct mei_cl *cl)
 920 {
 921         struct mei_device *dev;
 922         int rets;
 923
 924         if (WARN_ON(!cl || !cl->dev))
 925                 return -ENODEV;
 926
 927         dev = cl->dev;
 928
 929         cl_dbg(dev, cl, "disconnecting");
 930
 931         if (!mei_cl_is_connected(cl))
 932                 return 0;
 933
 934         if (mei_cl_is_fixed_address(cl)) {
 935                 mei_cl_set_disconnected(cl);
 936                 return 0;
 937         }
 938
 939         rets = pm_runtime_get(dev->dev);
 940         if (rets < 0 && rets != -EINPROGRESS) {
 941                 pm_runtime_put_noidle(dev->dev);
 942                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
 943                 return rets;
 944         }
 945
 946         rets = __mei_cl_disconnect(cl);
 947
 948         cl_dbg(dev, cl, "rpm: autosuspend\n");
 949         pm_runtime_mark_last_busy(dev->dev);
 950         pm_runtime_put_autosuspend(dev->dev);
 951
 952         return rets;
 953 }
 954
 955
 956 /**
 957  * mei_cl_is_other_connecting - checks if other
 958  *    client with the same me client id is connecting
 959  *
 960  * @cl: private data of the file object
 961  *
 962  * Return: true if other client is connected, false - otherwise.
 963  */
 964 static bool mei_cl_is_other_connecting(struct mei_cl *cl)
 965 {
 966         struct mei_device *dev;
 967         struct mei_cl_cb *cb;
 968
 969         dev = cl->dev;
 970
 971         list_for_each_entry(cb, &dev->ctrl_rd_list.list, list) {
 972                 if (cb->fop_type == MEI_FOP_CONNECT &&
 973                     mei_cl_me_id(cl) == mei_cl_me_id(cb->cl))
 974                         return true;
 975         }
 976
 977         return false;
 978 }
 979
 980 /**
 981  * mei_cl_send_connect - send connect request
 982  *
 983  * @cl: host client
 984  * @cb: callback block
 985  *
 986  * Return: 0, OK; otherwise, error.
 987  */
 988 static int mei_cl_send_connect(struct mei_cl *cl, struct mei_cl_cb *cb)
 989 {
 990         struct mei_device *dev;
 991         int ret;
 992
 993         dev = cl->dev;
 994
 995         ret = mei_hbm_cl_connect_req(dev, cl);
 996         cl->status = ret;
 997         if (ret) {
 998                 cl->state = MEI_FILE_DISCONNECT_REPLY;
 999                 return ret;
1000         }
1001
1002         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
1003         cl->timer_count = MEI_CONNECT_TIMEOUT;
1004         return 0;
1005 }
1006
1007 /**
1008  * mei_cl_irq_connect - send connect request in irq_thread context
1009  *
1010  * @cl: host client
1011  * @cb: callback block
1012  * @cmpl_list: complete list
1013  *
1014  * Return: 0, OK; otherwise, error.
1015  */
1016 int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
1017                               struct mei_cl_cb *cmpl_list)
1018 {
1019         struct mei_device *dev = cl->dev;
1020         u32 msg_slots;
1021         int slots;
1022         int rets;
1023
1024         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1025         slots = mei_hbuf_empty_slots(dev);
1026
1027         if (mei_cl_is_other_connecting(cl))
1028                 return 0;
1029
1030         if (slots < msg_slots)
1031                 return -EMSGSIZE;
1032
1033         rets = mei_cl_send_connect(cl, cb);
1034         if (rets)
1035                 list_move_tail(&cb->list, &cmpl_list->list);
1036
1037         return rets;
1038 }
1039
1040 /**
1041  * mei_cl_connect - connect host client to the me one
1042  *
1043  * @cl: host client
1044  * @me_cl: me client
1045  * @file: pointer to file structure
1046  *
1047  * Locking: called under "dev->device_lock" lock
1048  *
1049  * Return: 0 on success, <0 on failure.
1050  */
1051 int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
1052                   const struct file *file)
1053 {
1054         struct mei_device *dev;
1055         struct mei_cl_cb *cb;
1056         int rets;
1057
1058         if (WARN_ON(!cl || !cl->dev || !me_cl))
1059                 return -ENODEV;
1060
1061         dev = cl->dev;
1062
1063         rets = mei_cl_set_connecting(cl, me_cl);
1064         if (rets)
1065                 return rets;
1066
1067         if (mei_cl_is_fixed_address(cl)) {
1068                 cl->state = MEI_FILE_CONNECTED;
1069                 return 0;
1070         }
1071
1072         rets = pm_runtime_get(dev->dev);
1073         if (rets < 0 && rets != -EINPROGRESS) {
1074                 pm_runtime_put_noidle(dev->dev);
1075                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1076                 goto nortpm;
1077         }
1078
1079         cb = mei_io_cb_init(cl, MEI_FOP_CONNECT, file);
1080         rets = cb ? 0 : -ENOMEM;
1081         if (rets)
1082                 goto out;
1083
1084         list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
1085
1086         /* run hbuf acquire last so we don't have to undo */
1087         if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
1088                 rets = mei_cl_send_connect(cl, cb);
1089                 if (rets)
1090                         goto out;
1091         }
1092
1093         mutex_unlock(&dev->device_lock);
1094         wait_event_timeout(cl->wait,
1095                         (cl->state == MEI_FILE_CONNECTED ||
1096                          cl->state == MEI_FILE_DISCONNECTED ||
1097                          cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
1098                          cl->state == MEI_FILE_DISCONNECT_REPLY),
1099                         mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1100         mutex_lock(&dev->device_lock);
1101
1102         if (!mei_cl_is_connected(cl)) {
1103                 if (cl->state == MEI_FILE_DISCONNECT_REQUIRED) {
1104                         mei_io_list_flush(&dev->ctrl_rd_list, cl);
1105                         mei_io_list_flush(&dev->ctrl_wr_list, cl);
1106                          /* ignore disconnect return valuue;
1107                           * in case of failure reset will be invoked
1108                           */
1109                         __mei_cl_disconnect(cl);
1110                         rets = -EFAULT;
1111                         goto out;
1112                 }
1113
1114                 /* timeout or something went really wrong */
1115                 if (!cl->status)
1116                         cl->status = -EFAULT;
1117         }
1118
1119         rets = cl->status;
1120 out:
1121         cl_dbg(dev, cl, "rpm: autosuspend\n");
1122         pm_runtime_mark_last_busy(dev->dev);
1123         pm_runtime_put_autosuspend(dev->dev);
1124
1125         mei_io_cb_free(cb);
1126
1127 nortpm:
1128         if (!mei_cl_is_connected(cl))
1129                 mei_cl_set_disconnected(cl);
1130
1131         return rets;
1132 }
1133
1134 /**
1135  * mei_cl_alloc_linked - allocate and link host client
1136  *
1137  * @dev: the device structure
1138  *
1139  * Return: cl on success ERR_PTR on failure
1140  */
1141 struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev)
1142 {
1143         struct mei_cl *cl;
1144         int ret;
1145
1146         cl = mei_cl_allocate(dev);
1147         if (!cl) {
1148                 ret = -ENOMEM;
1149                 goto err;
1150         }
1151
1152         ret = mei_cl_link(cl);
1153         if (ret)
1154                 goto err;
1155
1156         return cl;
1157 err:
1158         kfree(cl);
1159         return ERR_PTR(ret);
1160 }
1161
1162
1163
1164 /**
1165  * mei_cl_flow_ctrl_creds - checks flow_control credits for cl.
1166  *
1167  * @cl: host client
1168  * @fp: the file pointer associated with the pointer
1169  *
1170  * Return: 1 if mei_flow_ctrl_creds >0, 0 - otherwise.
1171  */
1172 static int mei_cl_flow_ctrl_creds(struct mei_cl *cl, const struct file *fp)
1173 {
1174         int rets;
1175
1176         if (WARN_ON(!cl || !cl->me_cl))
1177                 return -EINVAL;
1178
1179         if (cl->mei_flow_ctrl_creds > 0)
1180                 return 1;
1181
1182         if (mei_cl_is_fixed_address(cl)) {
1183                 rets = mei_cl_read_start(cl, mei_cl_mtu(cl), fp);
1184                 if (rets && rets != -EBUSY)
1185                         return rets;
1186                 return 1;
1187         }
1188
1189         if (mei_cl_is_single_recv_buf(cl)) {
1190                 if (cl->me_cl->mei_flow_ctrl_creds > 0)
1191                         return 1;
1192         }
1193         return 0;
1194 }
1195
1196 /**
1197  * mei_cl_flow_ctrl_reduce - reduces flow_control.
1198  *
1199  * @cl: private data of the file object
1200  *
1201  * Return:
1202  *      0 on success
1203  *      -EINVAL when ctrl credits are <= 0
1204  */
1205 static int mei_cl_flow_ctrl_reduce(struct mei_cl *cl)
1206 {
1207         if (WARN_ON(!cl || !cl->me_cl))
1208                 return -EINVAL;
1209
1210         if (mei_cl_is_fixed_address(cl))
1211                 return 0;
1212
1213         if (mei_cl_is_single_recv_buf(cl)) {
1214                 if (WARN_ON(cl->me_cl->mei_flow_ctrl_creds <= 0))
1215                         return -EINVAL;
1216                 cl->me_cl->mei_flow_ctrl_creds--;
1217         } else {
1218                 if (WARN_ON(cl->mei_flow_ctrl_creds <= 0))
1219                         return -EINVAL;
1220                 cl->mei_flow_ctrl_creds--;
1221         }
1222         return 0;
1223 }
1224
1225 /**
1226  *  mei_cl_notify_fop2req - convert fop to proper request
1227  *
1228  * @fop: client notification start response command
1229  *
1230  * Return:  MEI_HBM_NOTIFICATION_START/STOP
1231  */
1232 u8 mei_cl_notify_fop2req(enum mei_cb_file_ops fop)
1233 {
1234         if (fop == MEI_FOP_NOTIFY_START)
1235                 return MEI_HBM_NOTIFICATION_START;
1236         else
1237                 return MEI_HBM_NOTIFICATION_STOP;
1238 }
1239
1240 /**
1241  *  mei_cl_notify_req2fop - convert notification request top file operation type
1242  *
1243  * @req: hbm notification request type
1244  *
1245  * Return:  MEI_FOP_NOTIFY_START/STOP
1246  */
1247 enum mei_cb_file_ops mei_cl_notify_req2fop(u8 req)
1248 {
1249         if (req == MEI_HBM_NOTIFICATION_START)
1250                 return MEI_FOP_NOTIFY_START;
1251         else
1252                 return MEI_FOP_NOTIFY_STOP;
1253 }
1254
1255 /**
1256  * mei_cl_irq_notify - send notification request in irq_thread context
1257  *
1258  * @cl: client
1259  * @cb: callback block.
1260  * @cmpl_list: complete list.
1261  *
1262  * Return: 0 on such and error otherwise.
1263  */
1264 int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
1265                       struct mei_cl_cb *cmpl_list)
1266 {
1267         struct mei_device *dev = cl->dev;
1268         u32 msg_slots;
1269         int slots;
1270         int ret;
1271         bool request;
1272
1273         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
1274         slots = mei_hbuf_empty_slots(dev);
1275
1276         if (slots < msg_slots)
1277                 return -EMSGSIZE;
1278
1279         request = mei_cl_notify_fop2req(cb->fop_type);
1280         ret = mei_hbm_cl_notify_req(dev, cl, request);
1281         if (ret) {
1282                 cl->status = ret;
1283                 list_move_tail(&cb->list, &cmpl_list->list);
1284                 return ret;
1285         }
1286
1287         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
1288         return 0;
1289 }
1290
1291 /**
1292  * mei_cl_notify_request - send notification stop/start request
1293  *
1294  * @cl: host client
1295  * @file: associate request with file
1296  * @request: 1 for start or 0 for stop
1297  *
1298  * Locking: called under "dev->device_lock" lock
1299  *
1300  * Return: 0 on such and error otherwise.
1301  */
1302 int mei_cl_notify_request(struct mei_cl *cl,
1303                           const struct file *file, u8 request)
1304 {
1305         struct mei_device *dev;
1306         struct mei_cl_cb *cb;
1307         enum mei_cb_file_ops fop_type;
1308         int rets;
1309
1310         if (WARN_ON(!cl || !cl->dev))
1311                 return -ENODEV;
1312
1313         dev = cl->dev;
1314
1315         if (!dev->hbm_f_ev_supported) {
1316                 cl_dbg(dev, cl, "notifications not supported\n");
1317                 return -EOPNOTSUPP;
1318         }
1319
1320         rets = pm_runtime_get(dev->dev);
1321         if (rets < 0 && rets != -EINPROGRESS) {
1322                 pm_runtime_put_noidle(dev->dev);
1323                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1324                 return rets;
1325         }
1326
1327         fop_type = mei_cl_notify_req2fop(request);
1328         cb = mei_io_cb_init(cl, fop_type, file);
1329         if (!cb) {
1330                 rets = -ENOMEM;
1331                 goto out;
1332         }
1333
1334         if (mei_hbuf_acquire(dev)) {
1335                 if (mei_hbm_cl_notify_req(dev, cl, request)) {
1336                         rets = -ENODEV;
1337                         goto out;
1338                 }
1339                 list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
1340         } else {
1341                 list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
1342         }
1343
1344         mutex_unlock(&dev->device_lock);
1345         wait_event_timeout(cl->wait,
1346                            cl->notify_en == request || !mei_cl_is_connected(cl),
1347                            mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
1348         mutex_lock(&dev->device_lock);
1349
1350         if (cl->notify_en != request && !cl->status)
1351                 cl->status = -EFAULT;
1352
1353         rets = cl->status;
1354
1355 out:
1356         cl_dbg(dev, cl, "rpm: autosuspend\n");
1357         pm_runtime_mark_last_busy(dev->dev);
1358         pm_runtime_put_autosuspend(dev->dev);
1359
1360         mei_io_cb_free(cb);
1361         return rets;
1362 }
1363
1364 /**
1365  * mei_cl_notify - raise notification
1366  *
1367  * @cl: host client
1368  *
1369  * Locking: called under "dev->device_lock" lock
1370  */
1371 void mei_cl_notify(struct mei_cl *cl)
1372 {
1373         struct mei_device *dev;
1374
1375         if (!cl || !cl->dev)
1376                 return;
1377
1378         dev = cl->dev;
1379
1380         if (!cl->notify_en)
1381                 return;
1382
1383         cl_dbg(dev, cl, "notify event");
1384         cl->notify_ev = true;
1385         if (!mei_cl_bus_notify_event(cl))
1386                 wake_up_interruptible(&cl->ev_wait);
1387
1388         if (cl->ev_async)
1389                 kill_fasync(&cl->ev_async, SIGIO, POLL_PRI);
1390
1391 }
1392
1393 /**
1394  * mei_cl_notify_get - get or wait for notification event
1395  *
1396  * @cl: host client
1397  * @block: this request is blocking
1398  * @notify_ev: true if notification event was received
1399  *
1400  * Locking: called under "dev->device_lock" lock
1401  *
1402  * Return: 0 on such and error otherwise.
1403  */
1404 int mei_cl_notify_get(struct mei_cl *cl, bool block, bool *notify_ev)
1405 {
1406         struct mei_device *dev;
1407         int rets;
1408
1409         *notify_ev = false;
1410
1411         if (WARN_ON(!cl || !cl->dev))
1412                 return -ENODEV;
1413
1414         dev = cl->dev;
1415
1416         if (!mei_cl_is_connected(cl))
1417                 return -ENODEV;
1418
1419         if (cl->notify_ev)
1420                 goto out;
1421
1422         if (!block)
1423                 return -EAGAIN;
1424
1425         mutex_unlock(&dev->device_lock);
1426         rets = wait_event_interruptible(cl->ev_wait, cl->notify_ev);
1427         mutex_lock(&dev->device_lock);
1428
1429         if (rets < 0)
1430                 return rets;
1431
1432 out:
1433         *notify_ev = cl->notify_ev;
1434         cl->notify_ev = false;
1435         return 0;
1436 }
1437
1438 /**
1439  * mei_cl_is_read_fc_cb - check if read cb is waiting for flow control
1440  *                        for given host client
1441  *
1442  * @cl: host client
1443  *
1444  * Return: true, if found at least one cb.
1445  */
1446 static bool mei_cl_is_read_fc_cb(struct mei_cl *cl)
1447 {
1448         struct mei_device *dev = cl->dev;
1449         struct mei_cl_cb *cb;
1450
1451         list_for_each_entry(cb, &dev->ctrl_wr_list.list, list)
1452                 if (cb->fop_type == MEI_FOP_READ && cb->cl == cl)
1453                         return true;
1454         return false;
1455 }
1456
1457 /**
1458  * mei_cl_read_start - the start read client message function.
1459  *
1460  * @cl: host client
1461  * @length: number of bytes to read
1462  * @fp: pointer to file structure
1463  *
1464  * Return: 0 on success, <0 on failure.
1465  */
1466 int mei_cl_read_start(struct mei_cl *cl, size_t length, const struct file *fp)
1467 {
1468         struct mei_device *dev;
1469         struct mei_cl_cb *cb;
1470         int rets;
1471
1472         if (WARN_ON(!cl || !cl->dev))
1473                 return -ENODEV;
1474
1475         dev = cl->dev;
1476
1477         if (!mei_cl_is_connected(cl))
1478                 return -ENODEV;
1479
1480         /* HW currently supports only one pending read */
1481         if (!list_empty(&cl->rd_pending) || mei_cl_is_read_fc_cb(cl))
1482                 return -EBUSY;
1483
1484         if (!mei_me_cl_is_active(cl->me_cl)) {
1485                 cl_err(dev, cl, "no such me client\n");
1486                 return  -ENOTTY;
1487         }
1488
1489         /* always allocate at least client max message */
1490         length = max_t(size_t, length, mei_cl_mtu(cl));
1491         cb = mei_cl_alloc_cb(cl, length, MEI_FOP_READ, fp);
1492         if (!cb)
1493                 return -ENOMEM;
1494
1495         if (mei_cl_is_fixed_address(cl)) {
1496                 list_add_tail(&cb->list, &cl->rd_pending);
1497                 return 0;
1498         }
1499
1500         rets = pm_runtime_get(dev->dev);
1501         if (rets < 0 && rets != -EINPROGRESS) {
1502                 pm_runtime_put_noidle(dev->dev);
1503                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1504                 goto nortpm;
1505         }
1506
1507         if (mei_hbuf_acquire(dev)) {
1508                 rets = mei_hbm_cl_flow_control_req(dev, cl);
1509                 if (rets < 0)
1510                         goto out;
1511
1512                 list_add_tail(&cb->list, &cl->rd_pending);
1513         } else {
1514                 rets = 0;
1515                 list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
1516         }
1517
1518 out:
1519         cl_dbg(dev, cl, "rpm: autosuspend\n");
1520         pm_runtime_mark_last_busy(dev->dev);
1521         pm_runtime_put_autosuspend(dev->dev);
1522 nortpm:
1523         if (rets)
1524                 mei_io_cb_free(cb);
1525
1526         return rets;
1527 }
1528
1529 /**
1530  * mei_cl_irq_write - write a message to device
1531  *      from the interrupt thread context
1532  *
1533  * @cl: client
1534  * @cb: callback block.
1535  * @cmpl_list: complete list.
1536  *
1537  * Return: 0, OK; otherwise error.
1538  */
1539 int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
1540                      struct mei_cl_cb *cmpl_list)
1541 {
1542         struct mei_device *dev;
1543         struct mei_msg_data *buf;
1544         struct mei_msg_hdr mei_hdr;
1545         size_t len;
1546         u32 msg_slots;
1547         int slots;
1548         int rets;
1549         bool first_chunk;
1550
1551         if (WARN_ON(!cl || !cl->dev))
1552                 return -ENODEV;
1553
1554         dev = cl->dev;
1555
1556         buf = &cb->buf;
1557
1558         first_chunk = cb->buf_idx == 0;
1559
1560         rets = first_chunk ? mei_cl_flow_ctrl_creds(cl, cb->fp) : 1;
1561         if (rets < 0)
1562                 return rets;
1563
1564         if (rets == 0) {
1565                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1566                 return 0;
1567         }
1568
1569         slots = mei_hbuf_empty_slots(dev);
1570         len = buf->size - cb->buf_idx;
1571         msg_slots = mei_data2slots(len);
1572
1573         mei_hdr.host_addr = mei_cl_host_addr(cl);
1574         mei_hdr.me_addr = mei_cl_me_id(cl);
1575         mei_hdr.reserved = 0;
1576         mei_hdr.internal = cb->internal;
1577
1578         if (slots >= msg_slots) {
1579                 mei_hdr.length = len;
1580                 mei_hdr.msg_complete = 1;
1581         /* Split the message only if we can write the whole host buffer */
1582         } else if (slots == dev->hbuf_depth) {
1583                 msg_slots = slots;
1584                 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
1585                 mei_hdr.length = len;
1586                 mei_hdr.msg_complete = 0;
1587         } else {
1588                 /* wait for next time the host buffer is empty */
1589                 return 0;
1590         }
1591
1592         cl_dbg(dev, cl, "buf: size = %zu idx = %zu\n",
1593                         cb->buf.size, cb->buf_idx);
1594
1595         rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
1596         if (rets) {
1597                 cl->status = rets;
1598                 list_move_tail(&cb->list, &cmpl_list->list);
1599                 return rets;
1600         }
1601
1602         cl->status = 0;
1603         cl->writing_state = MEI_WRITING;
1604         cb->buf_idx += mei_hdr.length;
1605         cb->completed = mei_hdr.msg_complete == 1;
1606
1607         if (first_chunk) {
1608                 if (mei_cl_flow_ctrl_reduce(cl))
1609                         return -EIO;
1610         }
1611
1612         if (mei_hdr.msg_complete)
1613                 list_move_tail(&cb->list, &dev->write_waiting_list.list);
1614
1615         return 0;
1616 }
1617
1618 /**
1619  * mei_cl_write - submit a write cb to mei device
1620  *      assumes device_lock is locked
1621  *
1622  * @cl: host client
1623  * @cb: write callback with filled data
1624  * @blocking: block until completed
1625  *
1626  * Return: number of bytes sent on success, <0 on failure.
1627  */
1628 int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking)
1629 {
1630         struct mei_device *dev;
1631         struct mei_msg_data *buf;
1632         struct mei_msg_hdr mei_hdr;
1633         int size;
1634         int rets;
1635
1636
1637         if (WARN_ON(!cl || !cl->dev))
1638                 return -ENODEV;
1639
1640         if (WARN_ON(!cb))
1641                 return -EINVAL;
1642
1643         dev = cl->dev;
1644
1645         buf = &cb->buf;
1646         size = buf->size;
1647
1648         cl_dbg(dev, cl, "size=%d\n", size);
1649
1650         rets = pm_runtime_get(dev->dev);
1651         if (rets < 0 && rets != -EINPROGRESS) {
1652                 pm_runtime_put_noidle(dev->dev);
1653                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
1654                 goto free;
1655         }
1656
1657         cb->buf_idx = 0;
1658         cl->writing_state = MEI_IDLE;
1659
1660         mei_hdr.host_addr = mei_cl_host_addr(cl);
1661         mei_hdr.me_addr = mei_cl_me_id(cl);
1662         mei_hdr.reserved = 0;
1663         mei_hdr.msg_complete = 0;
1664         mei_hdr.internal = cb->internal;
1665
1666         rets = mei_cl_flow_ctrl_creds(cl, cb->fp);
1667         if (rets < 0)
1668                 goto err;
1669
1670         if (rets == 0) {
1671                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
1672                 rets = size;
1673                 goto out;
1674         }
1675         if (!mei_hbuf_acquire(dev)) {
1676                 cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
1677                 rets = size;
1678                 goto out;
1679         }
1680
1681         /* Check for a maximum length */
1682         if (size > mei_hbuf_max_len(dev)) {
1683                 mei_hdr.length = mei_hbuf_max_len(dev);
1684                 mei_hdr.msg_complete = 0;
1685         } else {
1686                 mei_hdr.length = size;
1687                 mei_hdr.msg_complete = 1;
1688         }
1689
1690         rets = mei_write_message(dev, &mei_hdr, buf->data);
1691         if (rets)
1692                 goto err;
1693
1694         rets = mei_cl_flow_ctrl_reduce(cl);
1695         if (rets)
1696                 goto err;
1697
1698         cl->writing_state = MEI_WRITING;
1699         cb->buf_idx = mei_hdr.length;
1700         cb->completed = mei_hdr.msg_complete == 1;
1701
1702 out:
1703         if (mei_hdr.msg_complete)
1704                 list_add_tail(&cb->list, &dev->write_waiting_list.list);
1705         else
1706                 list_add_tail(&cb->list, &dev->write_list.list);
1707
1708         cb = NULL;
1709         if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
1710
1711                 mutex_unlock(&dev->device_lock);
1712                 rets = wait_event_interruptible(cl->tx_wait,
1713                                 cl->writing_state == MEI_WRITE_COMPLETE ||
1714                                 (!mei_cl_is_connected(cl)));
1715                 mutex_lock(&dev->device_lock);
1716                 /* wait_event_interruptible returns -ERESTARTSYS */
1717                 if (rets) {
1718                         if (signal_pending(current))
1719                                 rets = -EINTR;
1720                         goto err;
1721                 }
1722                 if (cl->writing_state != MEI_WRITE_COMPLETE) {
1723                         rets = -EFAULT;
1724                         goto err;
1725                 }
1726         }
1727
1728         rets = size;
1729 err:
1730         cl_dbg(dev, cl, "rpm: autosuspend\n");
1731         pm_runtime_mark_last_busy(dev->dev);
1732         pm_runtime_put_autosuspend(dev->dev);
1733 free:
1734         mei_io_cb_free(cb);
1735
1736         return rets;
1737 }
1738
1739
1740 /**
1741  * mei_cl_complete - processes completed operation for a client
1742  *
1743  * @cl: private data of the file object.
1744  * @cb: callback block.
1745  */
1746 void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
1747 {
1748         struct mei_device *dev = cl->dev;
1749
1750         switch (cb->fop_type) {
1751         case MEI_FOP_WRITE:
1752                 mei_io_cb_free(cb);
1753                 cl->writing_state = MEI_WRITE_COMPLETE;
1754                 if (waitqueue_active(&cl->tx_wait)) {
1755                         wake_up_interruptible(&cl->tx_wait);
1756                 } else {
1757                         pm_runtime_mark_last_busy(dev->dev);
1758                         pm_request_autosuspend(dev->dev);
1759                 }
1760                 break;
1761
1762         case MEI_FOP_READ:
1763                 list_add_tail(&cb->list, &cl->rd_completed);
1764                 if (!mei_cl_bus_rx_event(cl))
1765                         wake_up_interruptible(&cl->rx_wait);
1766                 break;
1767
1768         case MEI_FOP_CONNECT:
1769         case MEI_FOP_DISCONNECT:
1770         case MEI_FOP_NOTIFY_STOP:
1771         case MEI_FOP_NOTIFY_START:
1772                 if (waitqueue_active(&cl->wait))
1773                         wake_up(&cl->wait);
1774
1775                 break;
1776         case MEI_FOP_DISCONNECT_RSP:
1777                 mei_io_cb_free(cb);
1778                 mei_cl_set_disconnected(cl);
1779                 break;
1780         default:
1781                 BUG_ON(0);
1782         }
1783 }
1784
1785
1786 /**
1787  * mei_cl_all_disconnect - disconnect forcefully all connected clients
1788  *
1789  * @dev: mei device
1790  */
1791 void mei_cl_all_disconnect(struct mei_device *dev)
1792 {
1793         struct mei_cl *cl;
1794
1795         list_for_each_entry(cl, &dev->file_list, link)
1796                 mei_cl_set_disconnected(cl);
1797 }