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/pci.h>
  18 #include <linux/sched.h>
  19 #include <linux/wait.h>
  20 #include <linux/delay.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_by_uuid - locate index of me client
  31  *
  32  * @dev: mei device
  33  *
  34  * Locking: called under "dev->device_lock" lock
  35  *
  36  * returns me client or NULL if not found
  37  */
  38 struct mei_me_client *mei_me_cl_by_uuid(const struct mei_device *dev,
  39                                         const uuid_le *uuid)
  40 {
  41         struct mei_me_client *me_cl;
  42
  43         list_for_each_entry(me_cl, &dev->me_clients, list)
  44                 if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0)
  45                         return me_cl;
  46
  47         return NULL;
  48 }
  49
  50
  51 /**
  52  * mei_me_cl_by_id return index to me_clients for client_id
  53  *
  54  * @dev: the device structure
  55  * @client_id: me client id
  56  *
  57  * Locking: called under "dev->device_lock" lock
  58  *
  59  * returns me client or NULL if not found
  60  */
  61
  62 struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
  63 {
  64
  65         struct mei_me_client *me_cl;
  66
  67         list_for_each_entry(me_cl, &dev->me_clients, list)
  68                 if (me_cl->client_id == client_id)
  69                         return me_cl;
  70         return NULL;
  71 }
  72
  73
  74 /**
  75  * mei_cl_cmp_id - tells if the clients are the same
  76  *
  77  * @cl1: host client 1
  78  * @cl2: host client 2
  79  *
  80  * returns true  - if the clients has same host and me ids
  81  *         false - otherwise
  82  */
  83 static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
  84                                 const struct mei_cl *cl2)
  85 {
  86         return cl1 && cl2 &&
  87                 (cl1->host_client_id == cl2->host_client_id) &&
  88                 (cl1->me_client_id == cl2->me_client_id);
  89 }
  90
  91 /**
  92  * mei_io_list_flush - removes cbs belonging to cl.
  93  *
  94  * @list:  an instance of our list structure
  95  * @cl:    host client, can be NULL for flushing the whole list
  96  * @free:  whether to free the cbs
  97  */
  98 static void __mei_io_list_flush(struct mei_cl_cb *list,
  99                                 struct mei_cl *cl, bool free)
 100 {
 101         struct mei_cl_cb *cb;
 102         struct mei_cl_cb *next;
 103
 104         /* enable removing everything if no cl is specified */
 105         list_for_each_entry_safe(cb, next, &list->list, list) {
 106                 if (!cl || (cb->cl && mei_cl_cmp_id(cl, cb->cl))) {
 107                         list_del(&cb->list);
 108                         if (free)
 109                                 mei_io_cb_free(cb);
 110                 }
 111         }
 112 }
 113
 114 /**
 115  * mei_io_list_flush - removes list entry belonging to cl.
 116  *
 117  * @list:  An instance of our list structure
 118  * @cl: host client
 119  */
 120 void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl)
 121 {
 122         __mei_io_list_flush(list, cl, false);
 123 }
 124
 125
 126 /**
 127  * mei_io_list_free - removes cb belonging to cl and free them
 128  *
 129  * @list:  An instance of our list structure
 130  * @cl: host client
 131  */
 132 static inline void mei_io_list_free(struct mei_cl_cb *list, struct mei_cl *cl)
 133 {
 134         __mei_io_list_flush(list, cl, true);
 135 }
 136
 137 /**
 138  * mei_io_cb_free - free mei_cb_private related memory
 139  *
 140  * @cb: mei callback struct
 141  */
 142 void mei_io_cb_free(struct mei_cl_cb *cb)
 143 {
 144         if (cb == NULL)
 145                 return;
 146
 147         kfree(cb->request_buffer.data);
 148         kfree(cb->response_buffer.data);
 149         kfree(cb);
 150 }
 151
 152 /**
 153  * mei_io_cb_init - allocate and initialize io callback
 154  *
 155  * @cl - mei client
 156  * @fp: pointer to file structure
 157  *
 158  * returns mei_cl_cb pointer or NULL;
 159  */
 160 struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, struct file *fp)
 161 {
 162         struct mei_cl_cb *cb;
 163
 164         cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
 165         if (!cb)
 166                 return NULL;
 167
 168         mei_io_list_init(cb);
 169
 170         cb->file_object = fp;
 171         cb->cl = cl;
 172         cb->buf_idx = 0;
 173         return cb;
 174 }
 175
 176 /**
 177  * mei_io_cb_alloc_req_buf - allocate request buffer
 178  *
 179  * @cb: io callback structure
 180  * @length: size of the buffer
 181  *
 182  * returns 0 on success
 183  *         -EINVAL if cb is NULL
 184  *         -ENOMEM if allocation failed
 185  */
 186 int mei_io_cb_alloc_req_buf(struct mei_cl_cb *cb, size_t length)
 187 {
 188         if (!cb)
 189                 return -EINVAL;
 190
 191         if (length == 0)
 192                 return 0;
 193
 194         cb->request_buffer.data = kmalloc(length, GFP_KERNEL);
 195         if (!cb->request_buffer.data)
 196                 return -ENOMEM;
 197         cb->request_buffer.size = length;
 198         return 0;
 199 }
 200 /**
 201  * mei_io_cb_alloc_resp_buf - allocate response buffer
 202  *
 203  * @cb: io callback structure
 204  * @length: size of the buffer
 205  *
 206  * returns 0 on success
 207  *         -EINVAL if cb is NULL
 208  *         -ENOMEM if allocation failed
 209  */
 210 int mei_io_cb_alloc_resp_buf(struct mei_cl_cb *cb, size_t length)
 211 {
 212         if (!cb)
 213                 return -EINVAL;
 214
 215         if (length == 0)
 216                 return 0;
 217
 218         cb->response_buffer.data = kmalloc(length, GFP_KERNEL);
 219         if (!cb->response_buffer.data)
 220                 return -ENOMEM;
 221         cb->response_buffer.size = length;
 222         return 0;
 223 }
 224
 225
 226
 227 /**
 228  * mei_cl_flush_queues - flushes queue lists belonging to cl.
 229  *
 230  * @cl: host client
 231  */
 232 int mei_cl_flush_queues(struct mei_cl *cl)
 233 {
 234         struct mei_device *dev;
 235
 236         if (WARN_ON(!cl || !cl->dev))
 237                 return -EINVAL;
 238
 239         dev = cl->dev;
 240
 241         cl_dbg(dev, cl, "remove list entry belonging to cl\n");
 242         mei_io_list_flush(&cl->dev->read_list, cl);
 243         mei_io_list_free(&cl->dev->write_list, cl);
 244         mei_io_list_free(&cl->dev->write_waiting_list, cl);
 245         mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
 246         mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
 247         mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
 248         mei_io_list_flush(&cl->dev->amthif_rd_complete_list, cl);
 249         return 0;
 250 }
 251
 252
 253 /**
 254  * mei_cl_init - initializes cl.
 255  *
 256  * @cl: host client to be initialized
 257  * @dev: mei device
 258  */
 259 void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
 260 {
 261         memset(cl, 0, sizeof(struct mei_cl));
 262         init_waitqueue_head(&cl->wait);
 263         init_waitqueue_head(&cl->rx_wait);
 264         init_waitqueue_head(&cl->tx_wait);
 265         INIT_LIST_HEAD(&cl->link);
 266         INIT_LIST_HEAD(&cl->device_link);
 267         cl->reading_state = MEI_IDLE;
 268         cl->writing_state = MEI_IDLE;
 269         cl->dev = dev;
 270 }
 271
 272 /**
 273  * mei_cl_allocate - allocates cl  structure and sets it up.
 274  *
 275  * @dev: mei device
 276  * returns  The allocated file or NULL on failure
 277  */
 278 struct mei_cl *mei_cl_allocate(struct mei_device *dev)
 279 {
 280         struct mei_cl *cl;
 281
 282         cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
 283         if (!cl)
 284                 return NULL;
 285
 286         mei_cl_init(cl, dev);
 287
 288         return cl;
 289 }
 290
 291 /**
 292  * mei_cl_find_read_cb - find this cl's callback in the read list
 293  *
 294  * @cl: host client
 295  *
 296  * returns cb on success, NULL on error
 297  */
 298 struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl)
 299 {
 300         struct mei_device *dev = cl->dev;
 301         struct mei_cl_cb *cb;
 302
 303         list_for_each_entry(cb, &dev->read_list.list, list)
 304                 if (mei_cl_cmp_id(cl, cb->cl))
 305                         return cb;
 306         return NULL;
 307 }
 308
 309 /** mei_cl_link: allocate host id in the host map
 310  *
 311  * @cl - host client
 312  * @id - fixed host id or -1 for generic one
 313  *
 314  * returns 0 on success
 315  *      -EINVAL on incorrect values
 316  *      -ENONET if client not found
 317  */
 318 int mei_cl_link(struct mei_cl *cl, int id)
 319 {
 320         struct mei_device *dev;
 321         long open_handle_count;
 322
 323         if (WARN_ON(!cl || !cl->dev))
 324                 return -EINVAL;
 325
 326         dev = cl->dev;
 327
 328         /* If Id is not assigned get one*/
 329         if (id == MEI_HOST_CLIENT_ID_ANY)
 330                 id = find_first_zero_bit(dev->host_clients_map,
 331                                         MEI_CLIENTS_MAX);
 332
 333         if (id >= MEI_CLIENTS_MAX) {
 334                 dev_err(&dev->pdev->dev, "id exceeded %d", MEI_CLIENTS_MAX);
 335                 return -EMFILE;
 336         }
 337
 338         open_handle_count = dev->open_handle_count + dev->iamthif_open_count;
 339         if (open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
 340                 dev_err(&dev->pdev->dev, "open_handle_count exceeded %d",
 341                         MEI_MAX_OPEN_HANDLE_COUNT);
 342                 return -EMFILE;
 343         }
 344
 345         dev->open_handle_count++;
 346
 347         cl->host_client_id = id;
 348         list_add_tail(&cl->link, &dev->file_list);
 349
 350         set_bit(id, dev->host_clients_map);
 351
 352         cl->state = MEI_FILE_INITIALIZING;
 353
 354         cl_dbg(dev, cl, "link cl\n");
 355         return 0;
 356 }
 357
 358 /**
 359  * mei_cl_unlink - remove me_cl from the list
 360  *
 361  * @cl: host client
 362  */
 363 int mei_cl_unlink(struct mei_cl *cl)
 364 {
 365         struct mei_device *dev;
 366
 367         /* don't shout on error exit path */
 368         if (!cl)
 369                 return 0;
 370
 371         /* wd and amthif might not be initialized */
 372         if (!cl->dev)
 373                 return 0;
 374
 375         dev = cl->dev;
 376
 377         cl_dbg(dev, cl, "unlink client");
 378
 379         if (dev->open_handle_count > 0)
 380                 dev->open_handle_count--;
 381
 382         /* never clear the 0 bit */
 383         if (cl->host_client_id)
 384                 clear_bit(cl->host_client_id, dev->host_clients_map);
 385
 386         list_del_init(&cl->link);
 387
 388         cl->state = MEI_FILE_INITIALIZING;
 389
 390         return 0;
 391 }
 392
 393
 394 void mei_host_client_init(struct work_struct *work)
 395 {
 396         struct mei_device *dev = container_of(work,
 397                                               struct mei_device, init_work);
 398         struct mei_me_client *me_cl;
 399         struct mei_client_properties *props;
 400
 401         mutex_lock(&dev->device_lock);
 402
 403         list_for_each_entry(me_cl, &dev->me_clients, list) {
 404                 props = &me_cl->props;
 405
 406                 if (!uuid_le_cmp(props->protocol_name, mei_amthif_guid))
 407                         mei_amthif_host_init(dev);
 408                 else if (!uuid_le_cmp(props->protocol_name, mei_wd_guid))
 409                         mei_wd_host_init(dev);
 410                 else if (!uuid_le_cmp(props->protocol_name, mei_nfc_guid))
 411                         mei_nfc_host_init(dev);
 412
 413         }
 414
 415         dev->dev_state = MEI_DEV_ENABLED;
 416         dev->reset_count = 0;
 417
 418         mutex_unlock(&dev->device_lock);
 419
 420         pm_runtime_mark_last_busy(&dev->pdev->dev);
 421         dev_dbg(&dev->pdev->dev, "rpm: autosuspend\n");
 422         pm_runtime_autosuspend(&dev->pdev->dev);
 423 }
 424
 425 /**
 426  * mei_hbuf_acquire: try to acquire host buffer
 427  *
 428  * @dev: the device structure
 429  * returns true if host buffer was acquired
 430  */
 431 bool mei_hbuf_acquire(struct mei_device *dev)
 432 {
 433         if (mei_pg_state(dev) == MEI_PG_ON ||
 434             dev->pg_event == MEI_PG_EVENT_WAIT) {
 435                 dev_dbg(&dev->pdev->dev, "device is in pg\n");
 436                 return false;
 437         }
 438
 439         if (!dev->hbuf_is_ready) {
 440                 dev_dbg(&dev->pdev->dev, "hbuf is not ready\n");
 441                 return false;
 442         }
 443
 444         dev->hbuf_is_ready = false;
 445
 446         return true;
 447 }
 448
 449 /**
 450  * mei_cl_disconnect - disconnect host client from the me one
 451  *
 452  * @cl: host client
 453  *
 454  * Locking: called under "dev->device_lock" lock
 455  *
 456  * returns 0 on success, <0 on failure.
 457  */
 458 int mei_cl_disconnect(struct mei_cl *cl)
 459 {
 460         struct mei_device *dev;
 461         struct mei_cl_cb *cb;
 462         int rets;
 463
 464         if (WARN_ON(!cl || !cl->dev))
 465                 return -ENODEV;
 466
 467         dev = cl->dev;
 468
 469         cl_dbg(dev, cl, "disconnecting");
 470
 471         if (cl->state != MEI_FILE_DISCONNECTING)
 472                 return 0;
 473
 474         rets = pm_runtime_get(&dev->pdev->dev);
 475         if (rets < 0 && rets != -EINPROGRESS) {
 476                 pm_runtime_put_noidle(&dev->pdev->dev);
 477                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
 478                 return rets;
 479         }
 480
 481         cb = mei_io_cb_init(cl, NULL);
 482         if (!cb) {
 483                 rets = -ENOMEM;
 484                 goto free;
 485         }
 486
 487         cb->fop_type = MEI_FOP_CLOSE;
 488         if (mei_hbuf_acquire(dev)) {
 489                 if (mei_hbm_cl_disconnect_req(dev, cl)) {
 490                         rets = -ENODEV;
 491                         cl_err(dev, cl, "failed to disconnect.\n");
 492                         goto free;
 493                 }
 494                 cl->timer_count = MEI_CONNECT_TIMEOUT;
 495                 mdelay(10); /* Wait for hardware disconnection ready */
 496                 list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
 497         } else {
 498                 cl_dbg(dev, cl, "add disconnect cb to control write list\n");
 499                 list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
 500
 501         }
 502         mutex_unlock(&dev->device_lock);
 503
 504         wait_event_timeout(dev->wait_recvd_msg,
 505                         MEI_FILE_DISCONNECTED == cl->state,
 506                         mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 507
 508         mutex_lock(&dev->device_lock);
 509
 510         if (MEI_FILE_DISCONNECTED == cl->state) {
 511                 rets = 0;
 512                 cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
 513         } else {
 514                 cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
 515                 rets = -ETIME;
 516         }
 517
 518         mei_io_list_flush(&dev->ctrl_rd_list, cl);
 519         mei_io_list_flush(&dev->ctrl_wr_list, cl);
 520 free:
 521         cl_dbg(dev, cl, "rpm: autosuspend\n");
 522         pm_runtime_mark_last_busy(&dev->pdev->dev);
 523         pm_runtime_put_autosuspend(&dev->pdev->dev);
 524
 525         mei_io_cb_free(cb);
 526         return rets;
 527 }
 528
 529
 530 /**
 531  * mei_cl_is_other_connecting - checks if other
 532  *    client with the same me client id is connecting
 533  *
 534  * @cl: private data of the file object
 535  *
 536  * returns true if other client is connected, false - otherwise.
 537  */
 538 bool mei_cl_is_other_connecting(struct mei_cl *cl)
 539 {
 540         struct mei_device *dev;
 541         struct mei_cl *ocl; /* the other client */
 542
 543         if (WARN_ON(!cl || !cl->dev))
 544                 return false;
 545
 546         dev = cl->dev;
 547
 548         list_for_each_entry(ocl, &dev->file_list, link) {
 549                 if (ocl->state == MEI_FILE_CONNECTING &&
 550                     ocl != cl &&
 551                     cl->me_client_id == ocl->me_client_id)
 552                         return true;
 553
 554         }
 555
 556         return false;
 557 }
 558
 559 /**
 560  * mei_cl_connect - connect host client to the me one
 561  *
 562  * @cl: host client
 563  *
 564  * Locking: called under "dev->device_lock" lock
 565  *
 566  * returns 0 on success, <0 on failure.
 567  */
 568 int mei_cl_connect(struct mei_cl *cl, struct file *file)
 569 {
 570         struct mei_device *dev;
 571         struct mei_cl_cb *cb;
 572         int rets;
 573
 574         if (WARN_ON(!cl || !cl->dev))
 575                 return -ENODEV;
 576
 577         dev = cl->dev;
 578
 579         rets = pm_runtime_get(&dev->pdev->dev);
 580         if (rets < 0 && rets != -EINPROGRESS) {
 581                 pm_runtime_put_noidle(&dev->pdev->dev);
 582                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
 583                 return rets;
 584         }
 585
 586         cb = mei_io_cb_init(cl, file);
 587         if (!cb) {
 588                 rets = -ENOMEM;
 589                 goto out;
 590         }
 591
 592         cb->fop_type = MEI_FOP_CONNECT;
 593
 594         /* run hbuf acquire last so we don't have to undo */
 595         if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
 596                 cl->state = MEI_FILE_CONNECTING;
 597                 if (mei_hbm_cl_connect_req(dev, cl)) {
 598                         rets = -ENODEV;
 599                         goto out;
 600                 }
 601                 cl->timer_count = MEI_CONNECT_TIMEOUT;
 602                 list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
 603         } else {
 604                 cl->state = MEI_FILE_INITIALIZING;
 605                 list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
 606         }
 607
 608         mutex_unlock(&dev->device_lock);
 609         wait_event_timeout(dev->wait_recvd_msg,
 610                         (cl->state == MEI_FILE_CONNECTED ||
 611                          cl->state == MEI_FILE_DISCONNECTED),
 612                         mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
 613         mutex_lock(&dev->device_lock);
 614
 615         if (cl->state != MEI_FILE_CONNECTED) {
 616                 cl->state = MEI_FILE_DISCONNECTED;
 617                 /* something went really wrong */
 618                 if (!cl->status)
 619                         cl->status = -EFAULT;
 620
 621                 mei_io_list_flush(&dev->ctrl_rd_list, cl);
 622                 mei_io_list_flush(&dev->ctrl_wr_list, cl);
 623         }
 624
 625         rets = cl->status;
 626
 627 out:
 628         cl_dbg(dev, cl, "rpm: autosuspend\n");
 629         pm_runtime_mark_last_busy(&dev->pdev->dev);
 630         pm_runtime_put_autosuspend(&dev->pdev->dev);
 631
 632         mei_io_cb_free(cb);
 633         return rets;
 634 }
 635
 636 /**
 637  * mei_cl_flow_ctrl_creds - checks flow_control credits for cl.
 638  *
 639  * @cl: private data of the file object
 640  *
 641  * returns 1 if mei_flow_ctrl_creds >0, 0 - otherwise.
 642  *      -ENOENT if mei_cl is not present
 643  *      -EINVAL if single_recv_buf == 0
 644  */
 645 int mei_cl_flow_ctrl_creds(struct mei_cl *cl)
 646 {
 647         struct mei_device *dev;
 648         struct mei_me_client *me_cl;
 649
 650         if (WARN_ON(!cl || !cl->dev))
 651                 return -EINVAL;
 652
 653         dev = cl->dev;
 654
 655         if (cl->mei_flow_ctrl_creds > 0)
 656                 return 1;
 657
 658         me_cl = mei_me_cl_by_id(dev, cl->me_client_id);
 659         if (!me_cl) {
 660                 cl_err(dev, cl, "no such me client %d\n", cl->me_client_id);
 661                 return -ENOENT;
 662         }
 663
 664         if (me_cl->mei_flow_ctrl_creds) {
 665                 if (WARN_ON(me_cl->props.single_recv_buf == 0))
 666                         return -EINVAL;
 667                 return 1;
 668         }
 669         return 0;
 670 }
 671
 672 /**
 673  * mei_cl_flow_ctrl_reduce - reduces flow_control.
 674  *
 675  * @cl: private data of the file object
 676  *
 677  * @returns
 678  *      0 on success
 679  *      -ENOENT when me client is not found
 680  *      -EINVAL when ctrl credits are <= 0
 681  */
 682 int mei_cl_flow_ctrl_reduce(struct mei_cl *cl)
 683 {
 684         struct mei_device *dev;
 685         struct mei_me_client *me_cl;
 686
 687         if (WARN_ON(!cl || !cl->dev))
 688                 return -EINVAL;
 689
 690         dev = cl->dev;
 691
 692         me_cl = mei_me_cl_by_id(dev, cl->me_client_id);
 693         if (!me_cl) {
 694                 cl_err(dev, cl, "no such me client %d\n", cl->me_client_id);
 695                 return -ENOENT;
 696         }
 697
 698         if (me_cl->props.single_recv_buf) {
 699                 if (WARN_ON(me_cl->mei_flow_ctrl_creds <= 0))
 700                         return -EINVAL;
 701                 me_cl->mei_flow_ctrl_creds--;
 702         } else {
 703                 if (WARN_ON(cl->mei_flow_ctrl_creds <= 0))
 704                         return -EINVAL;
 705                 cl->mei_flow_ctrl_creds--;
 706         }
 707         return 0;
 708 }
 709
 710 /**
 711  * mei_cl_read_start - the start read client message function.
 712  *
 713  * @cl: host client
 714  *
 715  * returns 0 on success, <0 on failure.
 716  */
 717 int mei_cl_read_start(struct mei_cl *cl, size_t length)
 718 {
 719         struct mei_device *dev;
 720         struct mei_cl_cb *cb;
 721         struct mei_me_client *me_cl;
 722         int rets;
 723
 724         if (WARN_ON(!cl || !cl->dev))
 725                 return -ENODEV;
 726
 727         dev = cl->dev;
 728
 729         if (!mei_cl_is_connected(cl))
 730                 return -ENODEV;
 731
 732         if (cl->read_cb) {
 733                 cl_dbg(dev, cl, "read is pending.\n");
 734                 return -EBUSY;
 735         }
 736         me_cl = mei_me_cl_by_id(dev, cl->me_client_id);
 737         if (!me_cl) {
 738                 cl_err(dev, cl, "no such me client %d\n", cl->me_client_id);
 739                 return  -ENOTTY;
 740         }
 741
 742         rets = pm_runtime_get(&dev->pdev->dev);
 743         if (rets < 0 && rets != -EINPROGRESS) {
 744                 pm_runtime_put_noidle(&dev->pdev->dev);
 745                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
 746                 return rets;
 747         }
 748
 749         cb = mei_io_cb_init(cl, NULL);
 750         if (!cb) {
 751                 rets = -ENOMEM;
 752                 goto out;
 753         }
 754
 755         /* always allocate at least client max message */
 756         length = max_t(size_t, length, me_cl->props.max_msg_length);
 757         rets = mei_io_cb_alloc_resp_buf(cb, length);
 758         if (rets)
 759                 goto out;
 760
 761         cb->fop_type = MEI_FOP_READ;
 762         if (mei_hbuf_acquire(dev)) {
 763                 rets = mei_hbm_cl_flow_control_req(dev, cl);
 764                 if (rets < 0)
 765                         goto out;
 766
 767                 list_add_tail(&cb->list, &dev->read_list.list);
 768         } else {
 769                 list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
 770         }
 771
 772         cl->read_cb = cb;
 773
 774 out:
 775         cl_dbg(dev, cl, "rpm: autosuspend\n");
 776         pm_runtime_mark_last_busy(&dev->pdev->dev);
 777         pm_runtime_put_autosuspend(&dev->pdev->dev);
 778
 779         if (rets)
 780                 mei_io_cb_free(cb);
 781
 782         return rets;
 783 }
 784
 785 /**
 786  * mei_cl_irq_write - write a message to device
 787  *      from the interrupt thread context
 788  *
 789  * @cl: client
 790  * @cb: callback block.
 791  * @cmpl_list: complete list.
 792  *
 793  * returns 0, OK; otherwise error.
 794  */
 795 int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
 796                      struct mei_cl_cb *cmpl_list)
 797 {
 798         struct mei_device *dev;
 799         struct mei_msg_data *buf;
 800         struct mei_msg_hdr mei_hdr;
 801         size_t len;
 802         u32 msg_slots;
 803         int slots;
 804         int rets;
 805
 806         if (WARN_ON(!cl || !cl->dev))
 807                 return -ENODEV;
 808
 809         dev = cl->dev;
 810
 811         buf = &cb->request_buffer;
 812
 813         rets = mei_cl_flow_ctrl_creds(cl);
 814         if (rets < 0)
 815                 return rets;
 816
 817         if (rets == 0) {
 818                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
 819                 return 0;
 820         }
 821
 822         slots = mei_hbuf_empty_slots(dev);
 823         len = buf->size - cb->buf_idx;
 824         msg_slots = mei_data2slots(len);
 825
 826         mei_hdr.host_addr = cl->host_client_id;
 827         mei_hdr.me_addr = cl->me_client_id;
 828         mei_hdr.reserved = 0;
 829         mei_hdr.internal = cb->internal;
 830
 831         if (slots >= msg_slots) {
 832                 mei_hdr.length = len;
 833                 mei_hdr.msg_complete = 1;
 834         /* Split the message only if we can write the whole host buffer */
 835         } else if (slots == dev->hbuf_depth) {
 836                 msg_slots = slots;
 837                 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
 838                 mei_hdr.length = len;
 839                 mei_hdr.msg_complete = 0;
 840         } else {
 841                 /* wait for next time the host buffer is empty */
 842                 return 0;
 843         }
 844
 845         cl_dbg(dev, cl, "buf: size = %d idx = %lu\n",
 846                         cb->request_buffer.size, cb->buf_idx);
 847
 848         rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
 849         if (rets) {
 850                 cl->status = rets;
 851                 list_move_tail(&cb->list, &cmpl_list->list);
 852                 return rets;
 853         }
 854
 855         cl->status = 0;
 856         cl->writing_state = MEI_WRITING;
 857         cb->buf_idx += mei_hdr.length;
 858
 859         if (mei_hdr.msg_complete) {
 860                 if (mei_cl_flow_ctrl_reduce(cl))
 861                         return -EIO;
 862                 list_move_tail(&cb->list, &dev->write_waiting_list.list);
 863         }
 864
 865         return 0;
 866 }
 867
 868 /**
 869  * mei_cl_write - submit a write cb to mei device
 870         assumes device_lock is locked
 871  *
 872  * @cl: host client
 873  * @cl: write callback with filled data
 874  *
 875  * returns number of bytes sent on success, <0 on failure.
 876  */
 877 int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking)
 878 {
 879         struct mei_device *dev;
 880         struct mei_msg_data *buf;
 881         struct mei_msg_hdr mei_hdr;
 882         int rets;
 883
 884
 885         if (WARN_ON(!cl || !cl->dev))
 886                 return -ENODEV;
 887
 888         if (WARN_ON(!cb))
 889                 return -EINVAL;
 890
 891         dev = cl->dev;
 892
 893
 894         buf = &cb->request_buffer;
 895
 896         cl_dbg(dev, cl, "mei_cl_write %d\n", buf->size);
 897
 898         rets = pm_runtime_get(&dev->pdev->dev);
 899         if (rets < 0 && rets != -EINPROGRESS) {
 900                 pm_runtime_put_noidle(&dev->pdev->dev);
 901                 cl_err(dev, cl, "rpm: get failed %d\n", rets);
 902                 return rets;
 903         }
 904
 905         cb->fop_type = MEI_FOP_WRITE;
 906         cb->buf_idx = 0;
 907         cl->writing_state = MEI_IDLE;
 908
 909         mei_hdr.host_addr = cl->host_client_id;
 910         mei_hdr.me_addr = cl->me_client_id;
 911         mei_hdr.reserved = 0;
 912         mei_hdr.msg_complete = 0;
 913         mei_hdr.internal = cb->internal;
 914
 915         rets = mei_cl_flow_ctrl_creds(cl);
 916         if (rets < 0)
 917                 goto err;
 918
 919         if (rets == 0) {
 920                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
 921                 rets = buf->size;
 922                 goto out;
 923         }
 924         if (!mei_hbuf_acquire(dev)) {
 925                 cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
 926                 rets = buf->size;
 927                 goto out;
 928         }
 929
 930         /* Check for a maximum length */
 931         if (buf->size > mei_hbuf_max_len(dev)) {
 932                 mei_hdr.length = mei_hbuf_max_len(dev);
 933                 mei_hdr.msg_complete = 0;
 934         } else {
 935                 mei_hdr.length = buf->size;
 936                 mei_hdr.msg_complete = 1;
 937         }
 938
 939         rets = mei_write_message(dev, &mei_hdr, buf->data);
 940         if (rets)
 941                 goto err;
 942
 943         cl->writing_state = MEI_WRITING;
 944         cb->buf_idx = mei_hdr.length;
 945
 946 out:
 947         if (mei_hdr.msg_complete) {
 948                 rets = mei_cl_flow_ctrl_reduce(cl);
 949                 if (rets < 0)
 950                         goto err;
 951
 952                 list_add_tail(&cb->list, &dev->write_waiting_list.list);
 953         } else {
 954                 list_add_tail(&cb->list, &dev->write_list.list);
 955         }
 956
 957
 958         if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
 959
 960                 mutex_unlock(&dev->device_lock);
 961                 rets = wait_event_interruptible(cl->tx_wait,
 962                                 cl->writing_state == MEI_WRITE_COMPLETE);
 963                 mutex_lock(&dev->device_lock);
 964                 /* wait_event_interruptible returns -ERESTARTSYS */
 965                 if (rets) {
 966                         if (signal_pending(current))
 967                                 rets = -EINTR;
 968                         goto err;
 969                 }
 970         }
 971
 972         rets = buf->size;
 973 err:
 974         cl_dbg(dev, cl, "rpm: autosuspend\n");
 975         pm_runtime_mark_last_busy(&dev->pdev->dev);
 976         pm_runtime_put_autosuspend(&dev->pdev->dev);
 977
 978         return rets;
 979 }
 980
 981
 982 /**
 983  * mei_cl_complete - processes completed operation for a client
 984  *
 985  * @cl: private data of the file object.
 986  * @cb: callback block.
 987  */
 988 void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
 989 {
 990         if (cb->fop_type == MEI_FOP_WRITE) {
 991                 mei_io_cb_free(cb);
 992                 cb = NULL;
 993                 cl->writing_state = MEI_WRITE_COMPLETE;
 994                 if (waitqueue_active(&cl->tx_wait))
 995                         wake_up_interruptible(&cl->tx_wait);
 996
 997         } else if (cb->fop_type == MEI_FOP_READ &&
 998                         MEI_READING == cl->reading_state) {
 999                 cl->reading_state = MEI_READ_COMPLETE;
1000                 if (waitqueue_active(&cl->rx_wait))
1001                         wake_up_interruptible(&cl->rx_wait);
1002                 else
1003                         mei_cl_bus_rx_event(cl);
1004
1005         }
1006 }
1007
1008
1009 /**
1010  * mei_cl_all_disconnect - disconnect forcefully all connected clients
1011  *
1012  * @dev - mei device
1013  */
1014
1015 void mei_cl_all_disconnect(struct mei_device *dev)
1016 {
1017         struct mei_cl *cl;
1018
1019         list_for_each_entry(cl, &dev->file_list, link) {
1020                 cl->state = MEI_FILE_DISCONNECTED;
1021                 cl->mei_flow_ctrl_creds = 0;
1022                 cl->timer_count = 0;
1023         }
1024 }
1025
1026
1027 /**
1028  * mei_cl_all_wakeup  - wake up all readers and writers they can be interrupted
1029  *
1030  * @dev  - mei device
1031  */
1032 void mei_cl_all_wakeup(struct mei_device *dev)
1033 {
1034         struct mei_cl *cl;
1035         list_for_each_entry(cl, &dev->file_list, link) {
1036                 if (waitqueue_active(&cl->rx_wait)) {
1037                         cl_dbg(dev, cl, "Waking up reading client!\n");
1038                         wake_up_interruptible(&cl->rx_wait);
1039                 }
1040                 if (waitqueue_active(&cl->tx_wait)) {
1041                         cl_dbg(dev, cl, "Waking up writing client!\n");
1042                         wake_up_interruptible(&cl->tx_wait);
1043                 }
1044         }
1045 }
1046
1047 /**
1048  * mei_cl_all_write_clear - clear all pending writes
1049
1050  * @dev - mei device
1051  */
1052 void mei_cl_all_write_clear(struct mei_device *dev)
1053 {
1054         mei_io_list_free(&dev->write_list, NULL);
1055         mei_io_list_free(&dev->write_waiting_list, NULL);
1056 }
1057
1058