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) 52 kref_get(&me_cl->refcnt); 53 54 return me_cl; 55 } 56 57 /** 58 * mei_me_cl_release - unlink and 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 list_del(&me_cl->list); 69 kfree(me_cl); 70 } 71 /** 72 * mei_me_cl_put - decrease me client refcount and free client if necessary 73 * 74 * Locking: called under "dev->device_lock" lock 75 * 76 * @me_cl: me client 77 */ 78 void mei_me_cl_put(struct mei_me_client *me_cl) 79 { 80 if (me_cl) 81 kref_put(&me_cl->refcnt, mei_me_cl_release); 82 } 83 84 /** 85 * mei_me_cl_by_uuid - locate me client by uuid 86 * increases ref count 87 * 88 * @dev: mei device 89 * @uuid: me client uuid 90 * 91 * Locking: called under "dev->device_lock" lock 92 * 93 * Return: me client or NULL if not found 94 */ 95 struct mei_me_client *mei_me_cl_by_uuid(const struct mei_device *dev, 96 const uuid_le *uuid) 97 { 98 struct mei_me_client *me_cl; 99 100 list_for_each_entry(me_cl, &dev->me_clients, list) 101 if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0) 102 return mei_me_cl_get(me_cl); 103 104 return NULL; 105 } 106 107 /** 108 * mei_me_cl_by_id - locate me client by client id 109 * increases ref count 110 * 111 * @dev: the device structure 112 * @client_id: me client id 113 * 114 * Locking: called under "dev->device_lock" lock 115 * 116 * Return: me client or NULL if not found 117 */ 118 struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id) 119 { 120 121 struct mei_me_client *me_cl; 122 123 list_for_each_entry(me_cl, &dev->me_clients, list) 124 if (me_cl->client_id == client_id) 125 return mei_me_cl_get(me_cl); 126 127 return NULL; 128 } 129 130 /** 131 * mei_me_cl_by_uuid_id - locate me client by client id and uuid 132 * increases ref count 133 * 134 * @dev: the device structure 135 * @uuid: me client uuid 136 * @client_id: me client id 137 * 138 * Locking: called under "dev->device_lock" lock 139 * 140 * Return: me client or NULL if not found 141 */ 142 struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev, 143 const uuid_le *uuid, u8 client_id) 144 { 145 struct mei_me_client *me_cl; 146 147 list_for_each_entry(me_cl, &dev->me_clients, list) 148 if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0 && 149 me_cl->client_id == client_id) 150 return mei_me_cl_get(me_cl); 151 152 return NULL; 153 } 154 155 /** 156 * mei_me_cl_rm_by_uuid - remove all me clients matching uuid 157 * 158 * @dev: the device structure 159 * @uuid: me client uuid 160 * 161 * Locking: called under "dev->device_lock" lock 162 */ 163 void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid) 164 { 165 struct mei_me_client *me_cl, *next; 166 167 dev_dbg(dev->dev, "remove %pUl\n", uuid); 168 list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) 169 if (uuid_le_cmp(*uuid, me_cl->props.protocol_name) == 0) 170 mei_me_cl_put(me_cl); 171 } 172 173 /** 174 * mei_me_cl_rm_by_uuid_id - remove all me clients matching client id 175 * 176 * @dev: the device structure 177 * @uuid: me client uuid 178 * @id: me client id 179 * 180 * Locking: called under "dev->device_lock" lock 181 */ 182 void mei_me_cl_rm_by_uuid_id(struct mei_device *dev, const uuid_le *uuid, u8 id) 183 { 184 struct mei_me_client *me_cl, *next; 185 const uuid_le *pn; 186 187 dev_dbg(dev->dev, "remove %pUl %d\n", uuid, id); 188 list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) { 189 pn = &me_cl->props.protocol_name; 190 if (me_cl->client_id == id && uuid_le_cmp(*uuid, *pn) == 0) 191 mei_me_cl_put(me_cl); 192 } 193 } 194 195 /** 196 * mei_me_cl_rm_all - remove all me clients 197 * 198 * @dev: the device structure 199 * 200 * Locking: called under "dev->device_lock" lock 201 */ 202 void mei_me_cl_rm_all(struct mei_device *dev) 203 { 204 struct mei_me_client *me_cl, *next; 205 206 list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) 207 mei_me_cl_put(me_cl); 208 } 209 210 211 212 /** 213 * mei_cl_cmp_id - tells if the clients are the same 214 * 215 * @cl1: host client 1 216 * @cl2: host client 2 217 * 218 * Return: true - if the clients has same host and me ids 219 * false - otherwise 220 */ 221 static inline bool mei_cl_cmp_id(const struct mei_cl *cl1, 222 const struct mei_cl *cl2) 223 { 224 return cl1 && cl2 && 225 (cl1->host_client_id == cl2->host_client_id) && 226 (cl1->me_client_id == cl2->me_client_id); 227 } 228 229 /** 230 * mei_io_list_flush - removes cbs belonging to cl. 231 * 232 * @list: an instance of our list structure 233 * @cl: host client, can be NULL for flushing the whole list 234 * @free: whether to free the cbs 235 */ 236 static void __mei_io_list_flush(struct mei_cl_cb *list, 237 struct mei_cl *cl, bool free) 238 { 239 struct mei_cl_cb *cb; 240 struct mei_cl_cb *next; 241 242 /* enable removing everything if no cl is specified */ 243 list_for_each_entry_safe(cb, next, &list->list, list) { 244 if (!cl || mei_cl_cmp_id(cl, cb->cl)) { 245 list_del(&cb->list); 246 if (free) 247 mei_io_cb_free(cb); 248 } 249 } 250 } 251 252 /** 253 * mei_io_list_flush - removes list entry belonging to cl. 254 * 255 * @list: An instance of our list structure 256 * @cl: host client 257 */ 258 void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl) 259 { 260 __mei_io_list_flush(list, cl, false); 261 } 262 263 264 /** 265 * mei_io_list_free - removes cb belonging to cl and free them 266 * 267 * @list: An instance of our list structure 268 * @cl: host client 269 */ 270 static inline void mei_io_list_free(struct mei_cl_cb *list, struct mei_cl *cl) 271 { 272 __mei_io_list_flush(list, cl, true); 273 } 274 275 /** 276 * mei_io_cb_free - free mei_cb_private related memory 277 * 278 * @cb: mei callback struct 279 */ 280 void mei_io_cb_free(struct mei_cl_cb *cb) 281 { 282 if (cb == NULL) 283 return; 284 285 kfree(cb->request_buffer.data); 286 kfree(cb->response_buffer.data); 287 kfree(cb); 288 } 289 290 /** 291 * mei_io_cb_init - allocate and initialize io callback 292 * 293 * @cl: mei client 294 * @fp: pointer to file structure 295 * 296 * Return: mei_cl_cb pointer or NULL; 297 */ 298 struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, struct file *fp) 299 { 300 struct mei_cl_cb *cb; 301 302 cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL); 303 if (!cb) 304 return NULL; 305 306 mei_io_list_init(cb); 307 308 cb->file_object = fp; 309 cb->cl = cl; 310 cb->buf_idx = 0; 311 return cb; 312 } 313 314 /** 315 * mei_io_cb_alloc_req_buf - allocate request buffer 316 * 317 * @cb: io callback structure 318 * @length: size of the buffer 319 * 320 * Return: 0 on success 321 * -EINVAL if cb is NULL 322 * -ENOMEM if allocation failed 323 */ 324 int mei_io_cb_alloc_req_buf(struct mei_cl_cb *cb, size_t length) 325 { 326 if (!cb) 327 return -EINVAL; 328 329 if (length == 0) 330 return 0; 331 332 cb->request_buffer.data = kmalloc(length, GFP_KERNEL); 333 if (!cb->request_buffer.data) 334 return -ENOMEM; 335 cb->request_buffer.size = length; 336 return 0; 337 } 338 /** 339 * mei_io_cb_alloc_resp_buf - allocate response buffer 340 * 341 * @cb: io callback structure 342 * @length: size of the buffer 343 * 344 * Return: 0 on success 345 * -EINVAL if cb is NULL 346 * -ENOMEM if allocation failed 347 */ 348 int mei_io_cb_alloc_resp_buf(struct mei_cl_cb *cb, size_t length) 349 { 350 if (!cb) 351 return -EINVAL; 352 353 if (length == 0) 354 return 0; 355 356 cb->response_buffer.data = kmalloc(length, GFP_KERNEL); 357 if (!cb->response_buffer.data) 358 return -ENOMEM; 359 cb->response_buffer.size = length; 360 return 0; 361 } 362 363 364 365 /** 366 * mei_cl_flush_queues - flushes queue lists belonging to cl. 367 * 368 * @cl: host client 369 * 370 * Return: 0 on success, -EINVAL if cl or cl->dev is NULL. 371 */ 372 int mei_cl_flush_queues(struct mei_cl *cl) 373 { 374 struct mei_device *dev; 375 376 if (WARN_ON(!cl || !cl->dev)) 377 return -EINVAL; 378 379 dev = cl->dev; 380 381 cl_dbg(dev, cl, "remove list entry belonging to cl\n"); 382 mei_io_list_flush(&cl->dev->read_list, cl); 383 mei_io_list_free(&cl->dev->write_list, cl); 384 mei_io_list_free(&cl->dev->write_waiting_list, cl); 385 mei_io_list_flush(&cl->dev->ctrl_wr_list, cl); 386 mei_io_list_flush(&cl->dev->ctrl_rd_list, cl); 387 mei_io_list_flush(&cl->dev->amthif_cmd_list, cl); 388 mei_io_list_flush(&cl->dev->amthif_rd_complete_list, cl); 389 return 0; 390 } 391 392 393 /** 394 * mei_cl_init - initializes cl. 395 * 396 * @cl: host client to be initialized 397 * @dev: mei device 398 */ 399 void mei_cl_init(struct mei_cl *cl, struct mei_device *dev) 400 { 401 memset(cl, 0, sizeof(struct mei_cl)); 402 init_waitqueue_head(&cl->wait); 403 init_waitqueue_head(&cl->rx_wait); 404 init_waitqueue_head(&cl->tx_wait); 405 INIT_LIST_HEAD(&cl->link); 406 INIT_LIST_HEAD(&cl->device_link); 407 cl->reading_state = MEI_IDLE; 408 cl->writing_state = MEI_IDLE; 409 cl->dev = dev; 410 } 411 412 /** 413 * mei_cl_allocate - allocates cl structure and sets it up. 414 * 415 * @dev: mei device 416 * Return: The allocated file or NULL on failure 417 */ 418 struct mei_cl *mei_cl_allocate(struct mei_device *dev) 419 { 420 struct mei_cl *cl; 421 422 cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL); 423 if (!cl) 424 return NULL; 425 426 mei_cl_init(cl, dev); 427 428 return cl; 429 } 430 431 /** 432 * mei_cl_find_read_cb - find this cl's callback in the read list 433 * 434 * @cl: host client 435 * 436 * Return: cb on success, NULL on error 437 */ 438 struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl) 439 { 440 struct mei_device *dev = cl->dev; 441 struct mei_cl_cb *cb; 442 443 list_for_each_entry(cb, &dev->read_list.list, list) 444 if (mei_cl_cmp_id(cl, cb->cl)) 445 return cb; 446 return NULL; 447 } 448 449 /** mei_cl_link: allocate host id in the host map 450 * 451 * @cl - host client 452 * @id - fixed host id or -1 for generic one 453 * 454 * Return: 0 on success 455 * -EINVAL on incorrect values 456 * -ENONET if client not found 457 */ 458 int mei_cl_link(struct mei_cl *cl, int id) 459 { 460 struct mei_device *dev; 461 long open_handle_count; 462 463 if (WARN_ON(!cl || !cl->dev)) 464 return -EINVAL; 465 466 dev = cl->dev; 467 468 /* If Id is not assigned get one*/ 469 if (id == MEI_HOST_CLIENT_ID_ANY) 470 id = find_first_zero_bit(dev->host_clients_map, 471 MEI_CLIENTS_MAX); 472 473 if (id >= MEI_CLIENTS_MAX) { 474 dev_err(dev->dev, "id exceeded %d", MEI_CLIENTS_MAX); 475 return -EMFILE; 476 } 477 478 open_handle_count = dev->open_handle_count + dev->iamthif_open_count; 479 if (open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) { 480 dev_err(dev->dev, "open_handle_count exceeded %d", 481 MEI_MAX_OPEN_HANDLE_COUNT); 482 return -EMFILE; 483 } 484 485 dev->open_handle_count++; 486 487 cl->host_client_id = id; 488 list_add_tail(&cl->link, &dev->file_list); 489 490 set_bit(id, dev->host_clients_map); 491 492 cl->state = MEI_FILE_INITIALIZING; 493 494 cl_dbg(dev, cl, "link cl\n"); 495 return 0; 496 } 497 498 /** 499 * mei_cl_unlink - remove me_cl from the list 500 * 501 * @cl: host client 502 * 503 * Return: always 0 504 */ 505 int mei_cl_unlink(struct mei_cl *cl) 506 { 507 struct mei_device *dev; 508 509 /* don't shout on error exit path */ 510 if (!cl) 511 return 0; 512 513 /* wd and amthif might not be initialized */ 514 if (!cl->dev) 515 return 0; 516 517 dev = cl->dev; 518 519 cl_dbg(dev, cl, "unlink client"); 520 521 if (dev->open_handle_count > 0) 522 dev->open_handle_count--; 523 524 /* never clear the 0 bit */ 525 if (cl->host_client_id) 526 clear_bit(cl->host_client_id, dev->host_clients_map); 527 528 list_del_init(&cl->link); 529 530 cl->state = MEI_FILE_INITIALIZING; 531 532 return 0; 533 } 534 535 536 void mei_host_client_init(struct work_struct *work) 537 { 538 struct mei_device *dev = container_of(work, 539 struct mei_device, init_work); 540 struct mei_me_client *me_cl; 541 struct mei_client_properties *props; 542 543 mutex_lock(&dev->device_lock); 544 545 list_for_each_entry(me_cl, &dev->me_clients, list) { 546 props = &me_cl->props; 547 548 if (!uuid_le_cmp(props->protocol_name, mei_amthif_guid)) 549 mei_amthif_host_init(dev); 550 else if (!uuid_le_cmp(props->protocol_name, mei_wd_guid)) 551 mei_wd_host_init(dev); 552 else if (!uuid_le_cmp(props->protocol_name, mei_nfc_guid)) 553 mei_nfc_host_init(dev); 554 555 } 556 557 dev->dev_state = MEI_DEV_ENABLED; 558 dev->reset_count = 0; 559 560 mutex_unlock(&dev->device_lock); 561 562 pm_runtime_mark_last_busy(dev->dev); 563 dev_dbg(dev->dev, "rpm: autosuspend\n"); 564 pm_runtime_autosuspend(dev->dev); 565 } 566 567 /** 568 * mei_hbuf_acquire - try to acquire host buffer 569 * 570 * @dev: the device structure 571 * Return: true if host buffer was acquired 572 */ 573 bool mei_hbuf_acquire(struct mei_device *dev) 574 { 575 if (mei_pg_state(dev) == MEI_PG_ON || 576 dev->pg_event == MEI_PG_EVENT_WAIT) { 577 dev_dbg(dev->dev, "device is in pg\n"); 578 return false; 579 } 580 581 if (!dev->hbuf_is_ready) { 582 dev_dbg(dev->dev, "hbuf is not ready\n"); 583 return false; 584 } 585 586 dev->hbuf_is_ready = false; 587 588 return true; 589 } 590 591 /** 592 * mei_cl_disconnect - disconnect host client from the me one 593 * 594 * @cl: host client 595 * 596 * Locking: called under "dev->device_lock" lock 597 * 598 * Return: 0 on success, <0 on failure. 599 */ 600 int mei_cl_disconnect(struct mei_cl *cl) 601 { 602 struct mei_device *dev; 603 struct mei_cl_cb *cb; 604 int rets; 605 606 if (WARN_ON(!cl || !cl->dev)) 607 return -ENODEV; 608 609 dev = cl->dev; 610 611 cl_dbg(dev, cl, "disconnecting"); 612 613 if (cl->state != MEI_FILE_DISCONNECTING) 614 return 0; 615 616 rets = pm_runtime_get(dev->dev); 617 if (rets < 0 && rets != -EINPROGRESS) { 618 pm_runtime_put_noidle(dev->dev); 619 cl_err(dev, cl, "rpm: get failed %d\n", rets); 620 return rets; 621 } 622 623 cb = mei_io_cb_init(cl, NULL); 624 if (!cb) { 625 rets = -ENOMEM; 626 goto free; 627 } 628 629 cb->fop_type = MEI_FOP_DISCONNECT; 630 631 if (mei_hbuf_acquire(dev)) { 632 if (mei_hbm_cl_disconnect_req(dev, cl)) { 633 rets = -ENODEV; 634 cl_err(dev, cl, "failed to disconnect.\n"); 635 goto free; 636 } 637 cl->timer_count = MEI_CONNECT_TIMEOUT; 638 mdelay(10); /* Wait for hardware disconnection ready */ 639 list_add_tail(&cb->list, &dev->ctrl_rd_list.list); 640 } else { 641 cl_dbg(dev, cl, "add disconnect cb to control write list\n"); 642 list_add_tail(&cb->list, &dev->ctrl_wr_list.list); 643 644 } 645 mutex_unlock(&dev->device_lock); 646 647 wait_event_timeout(cl->wait, 648 MEI_FILE_DISCONNECTED == cl->state, 649 mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT)); 650 651 mutex_lock(&dev->device_lock); 652 653 if (MEI_FILE_DISCONNECTED == cl->state) { 654 rets = 0; 655 cl_dbg(dev, cl, "successfully disconnected from FW client.\n"); 656 } else { 657 cl_dbg(dev, cl, "timeout on disconnect from FW client.\n"); 658 rets = -ETIME; 659 } 660 661 mei_io_list_flush(&dev->ctrl_rd_list, cl); 662 mei_io_list_flush(&dev->ctrl_wr_list, cl); 663 free: 664 cl_dbg(dev, cl, "rpm: autosuspend\n"); 665 pm_runtime_mark_last_busy(dev->dev); 666 pm_runtime_put_autosuspend(dev->dev); 667 668 mei_io_cb_free(cb); 669 return rets; 670 } 671 672 673 /** 674 * mei_cl_is_other_connecting - checks if other 675 * client with the same me client id is connecting 676 * 677 * @cl: private data of the file object 678 * 679 * Return: true if other client is connected, false - otherwise. 680 */ 681 bool mei_cl_is_other_connecting(struct mei_cl *cl) 682 { 683 struct mei_device *dev; 684 struct mei_cl *ocl; /* the other client */ 685 686 if (WARN_ON(!cl || !cl->dev)) 687 return false; 688 689 dev = cl->dev; 690 691 list_for_each_entry(ocl, &dev->file_list, link) { 692 if (ocl->state == MEI_FILE_CONNECTING && 693 ocl != cl && 694 cl->me_client_id == ocl->me_client_id) 695 return true; 696 697 } 698 699 return false; 700 } 701 702 /** 703 * mei_cl_connect - connect host client to the me one 704 * 705 * @cl: host client 706 * @file: pointer to file structure 707 * 708 * Locking: called under "dev->device_lock" lock 709 * 710 * Return: 0 on success, <0 on failure. 711 */ 712 int mei_cl_connect(struct mei_cl *cl, struct file *file) 713 { 714 struct mei_device *dev; 715 struct mei_cl_cb *cb; 716 int rets; 717 718 if (WARN_ON(!cl || !cl->dev)) 719 return -ENODEV; 720 721 dev = cl->dev; 722 723 rets = pm_runtime_get(dev->dev); 724 if (rets < 0 && rets != -EINPROGRESS) { 725 pm_runtime_put_noidle(dev->dev); 726 cl_err(dev, cl, "rpm: get failed %d\n", rets); 727 return rets; 728 } 729 730 cb = mei_io_cb_init(cl, file); 731 if (!cb) { 732 rets = -ENOMEM; 733 goto out; 734 } 735 736 cb->fop_type = MEI_FOP_CONNECT; 737 738 /* run hbuf acquire last so we don't have to undo */ 739 if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) { 740 cl->state = MEI_FILE_CONNECTING; 741 if (mei_hbm_cl_connect_req(dev, cl)) { 742 rets = -ENODEV; 743 goto out; 744 } 745 cl->timer_count = MEI_CONNECT_TIMEOUT; 746 list_add_tail(&cb->list, &dev->ctrl_rd_list.list); 747 } else { 748 cl->state = MEI_FILE_INITIALIZING; 749 list_add_tail(&cb->list, &dev->ctrl_wr_list.list); 750 } 751 752 mutex_unlock(&dev->device_lock); 753 wait_event_timeout(cl->wait, 754 (cl->state == MEI_FILE_CONNECTED || 755 cl->state == MEI_FILE_DISCONNECTED), 756 mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT)); 757 mutex_lock(&dev->device_lock); 758 759 if (cl->state != MEI_FILE_CONNECTED) { 760 cl->state = MEI_FILE_DISCONNECTED; 761 /* something went really wrong */ 762 if (!cl->status) 763 cl->status = -EFAULT; 764 765 mei_io_list_flush(&dev->ctrl_rd_list, cl); 766 mei_io_list_flush(&dev->ctrl_wr_list, cl); 767 } 768 769 rets = cl->status; 770 771 out: 772 cl_dbg(dev, cl, "rpm: autosuspend\n"); 773 pm_runtime_mark_last_busy(dev->dev); 774 pm_runtime_put_autosuspend(dev->dev); 775 776 mei_io_cb_free(cb); 777 return rets; 778 } 779 780 /** 781 * mei_cl_flow_ctrl_creds - checks flow_control credits for cl. 782 * 783 * @cl: private data of the file object 784 * 785 * Return: 1 if mei_flow_ctrl_creds >0, 0 - otherwise. 786 * -ENOENT if mei_cl is not present 787 * -EINVAL if single_recv_buf == 0 788 */ 789 int mei_cl_flow_ctrl_creds(struct mei_cl *cl) 790 { 791 struct mei_device *dev; 792 struct mei_me_client *me_cl; 793 int rets = 0; 794 795 if (WARN_ON(!cl || !cl->dev)) 796 return -EINVAL; 797 798 dev = cl->dev; 799 800 if (cl->mei_flow_ctrl_creds > 0) 801 return 1; 802 803 me_cl = mei_me_cl_by_uuid_id(dev, &cl->cl_uuid, cl->me_client_id); 804 if (!me_cl) { 805 cl_err(dev, cl, "no such me client %d\n", cl->me_client_id); 806 return -ENOENT; 807 } 808 809 if (me_cl->mei_flow_ctrl_creds > 0) { 810 rets = 1; 811 if (WARN_ON(me_cl->props.single_recv_buf == 0)) 812 rets = -EINVAL; 813 } 814 mei_me_cl_put(me_cl); 815 return rets; 816 } 817 818 /** 819 * mei_cl_flow_ctrl_reduce - reduces flow_control. 820 * 821 * @cl: private data of the file object 822 * 823 * Return: 824 * 0 on success 825 * -ENOENT when me client is not found 826 * -EINVAL when ctrl credits are <= 0 827 */ 828 int mei_cl_flow_ctrl_reduce(struct mei_cl *cl) 829 { 830 struct mei_device *dev; 831 struct mei_me_client *me_cl; 832 int rets; 833 834 if (WARN_ON(!cl || !cl->dev)) 835 return -EINVAL; 836 837 dev = cl->dev; 838 839 me_cl = mei_me_cl_by_uuid_id(dev, &cl->cl_uuid, cl->me_client_id); 840 if (!me_cl) { 841 cl_err(dev, cl, "no such me client %d\n", cl->me_client_id); 842 return -ENOENT; 843 } 844 845 if (me_cl->props.single_recv_buf) { 846 if (WARN_ON(me_cl->mei_flow_ctrl_creds <= 0)) { 847 rets = -EINVAL; 848 goto out; 849 } 850 me_cl->mei_flow_ctrl_creds--; 851 } else { 852 if (WARN_ON(cl->mei_flow_ctrl_creds <= 0)) { 853 rets = -EINVAL; 854 goto out; 855 } 856 cl->mei_flow_ctrl_creds--; 857 } 858 rets = 0; 859 out: 860 mei_me_cl_put(me_cl); 861 return rets; 862 } 863 864 /** 865 * mei_cl_read_start - the start read client message function. 866 * 867 * @cl: host client 868 * @length: number of bytes to read 869 * 870 * Return: 0 on success, <0 on failure. 871 */ 872 int mei_cl_read_start(struct mei_cl *cl, size_t length) 873 { 874 struct mei_device *dev; 875 struct mei_cl_cb *cb; 876 struct mei_me_client *me_cl; 877 int rets; 878 879 if (WARN_ON(!cl || !cl->dev)) 880 return -ENODEV; 881 882 dev = cl->dev; 883 884 if (!mei_cl_is_connected(cl)) 885 return -ENODEV; 886 887 if (cl->read_cb) { 888 cl_dbg(dev, cl, "read is pending.\n"); 889 return -EBUSY; 890 } 891 me_cl = mei_me_cl_by_uuid_id(dev, &cl->cl_uuid, cl->me_client_id); 892 if (!me_cl) { 893 cl_err(dev, cl, "no such me client %d\n", cl->me_client_id); 894 return -ENOTTY; 895 } 896 /* always allocate at least client max message */ 897 length = max_t(size_t, length, me_cl->props.max_msg_length); 898 mei_me_cl_put(me_cl); 899 900 rets = pm_runtime_get(dev->dev); 901 if (rets < 0 && rets != -EINPROGRESS) { 902 pm_runtime_put_noidle(dev->dev); 903 cl_err(dev, cl, "rpm: get failed %d\n", rets); 904 return rets; 905 } 906 907 cb = mei_io_cb_init(cl, NULL); 908 if (!cb) { 909 rets = -ENOMEM; 910 goto out; 911 } 912 913 rets = mei_io_cb_alloc_resp_buf(cb, length); 914 if (rets) 915 goto out; 916 917 cb->fop_type = MEI_FOP_READ; 918 if (mei_hbuf_acquire(dev)) { 919 rets = mei_hbm_cl_flow_control_req(dev, cl); 920 if (rets < 0) 921 goto out; 922 923 list_add_tail(&cb->list, &dev->read_list.list); 924 } else { 925 list_add_tail(&cb->list, &dev->ctrl_wr_list.list); 926 } 927 928 cl->read_cb = cb; 929 930 out: 931 cl_dbg(dev, cl, "rpm: autosuspend\n"); 932 pm_runtime_mark_last_busy(dev->dev); 933 pm_runtime_put_autosuspend(dev->dev); 934 935 if (rets) 936 mei_io_cb_free(cb); 937 938 return rets; 939 } 940 941 /** 942 * mei_cl_irq_write - write a message to device 943 * from the interrupt thread context 944 * 945 * @cl: client 946 * @cb: callback block. 947 * @cmpl_list: complete list. 948 * 949 * Return: 0, OK; otherwise error. 950 */ 951 int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb, 952 struct mei_cl_cb *cmpl_list) 953 { 954 struct mei_device *dev; 955 struct mei_msg_data *buf; 956 struct mei_msg_hdr mei_hdr; 957 size_t len; 958 u32 msg_slots; 959 int slots; 960 int rets; 961 962 if (WARN_ON(!cl || !cl->dev)) 963 return -ENODEV; 964 965 dev = cl->dev; 966 967 buf = &cb->request_buffer; 968 969 rets = mei_cl_flow_ctrl_creds(cl); 970 if (rets < 0) 971 return rets; 972 973 if (rets == 0) { 974 cl_dbg(dev, cl, "No flow control credentials: not sending.\n"); 975 return 0; 976 } 977 978 slots = mei_hbuf_empty_slots(dev); 979 len = buf->size - cb->buf_idx; 980 msg_slots = mei_data2slots(len); 981 982 mei_hdr.host_addr = cl->host_client_id; 983 mei_hdr.me_addr = cl->me_client_id; 984 mei_hdr.reserved = 0; 985 mei_hdr.internal = cb->internal; 986 987 if (slots >= msg_slots) { 988 mei_hdr.length = len; 989 mei_hdr.msg_complete = 1; 990 /* Split the message only if we can write the whole host buffer */ 991 } else if (slots == dev->hbuf_depth) { 992 msg_slots = slots; 993 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr); 994 mei_hdr.length = len; 995 mei_hdr.msg_complete = 0; 996 } else { 997 /* wait for next time the host buffer is empty */ 998 return 0; 999 } 1000 1001 cl_dbg(dev, cl, "buf: size = %d idx = %lu\n", 1002 cb->request_buffer.size, cb->buf_idx); 1003 1004 rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx); 1005 if (rets) { 1006 cl->status = rets; 1007 list_move_tail(&cb->list, &cmpl_list->list); 1008 return rets; 1009 } 1010 1011 cl->status = 0; 1012 cl->writing_state = MEI_WRITING; 1013 cb->buf_idx += mei_hdr.length; 1014 1015 if (mei_hdr.msg_complete) { 1016 if (mei_cl_flow_ctrl_reduce(cl)) 1017 return -EIO; 1018 list_move_tail(&cb->list, &dev->write_waiting_list.list); 1019 } 1020 1021 return 0; 1022 } 1023 1024 /** 1025 * mei_cl_write - submit a write cb to mei device 1026 * assumes device_lock is locked 1027 * 1028 * @cl: host client 1029 * @cb: write callback with filled data 1030 * @blocking: block until completed 1031 * 1032 * Return: number of bytes sent on success, <0 on failure. 1033 */ 1034 int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking) 1035 { 1036 struct mei_device *dev; 1037 struct mei_msg_data *buf; 1038 struct mei_msg_hdr mei_hdr; 1039 int rets; 1040 1041 1042 if (WARN_ON(!cl || !cl->dev)) 1043 return -ENODEV; 1044 1045 if (WARN_ON(!cb)) 1046 return -EINVAL; 1047 1048 dev = cl->dev; 1049 1050 1051 buf = &cb->request_buffer; 1052 1053 cl_dbg(dev, cl, "size=%d\n", buf->size); 1054 1055 rets = pm_runtime_get(dev->dev); 1056 if (rets < 0 && rets != -EINPROGRESS) { 1057 pm_runtime_put_noidle(dev->dev); 1058 cl_err(dev, cl, "rpm: get failed %d\n", rets); 1059 return rets; 1060 } 1061 1062 cb->fop_type = MEI_FOP_WRITE; 1063 cb->buf_idx = 0; 1064 cl->writing_state = MEI_IDLE; 1065 1066 mei_hdr.host_addr = cl->host_client_id; 1067 mei_hdr.me_addr = cl->me_client_id; 1068 mei_hdr.reserved = 0; 1069 mei_hdr.msg_complete = 0; 1070 mei_hdr.internal = cb->internal; 1071 1072 rets = mei_cl_flow_ctrl_creds(cl); 1073 if (rets < 0) 1074 goto err; 1075 1076 if (rets == 0) { 1077 cl_dbg(dev, cl, "No flow control credentials: not sending.\n"); 1078 rets = buf->size; 1079 goto out; 1080 } 1081 if (!mei_hbuf_acquire(dev)) { 1082 cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n"); 1083 rets = buf->size; 1084 goto out; 1085 } 1086 1087 /* Check for a maximum length */ 1088 if (buf->size > mei_hbuf_max_len(dev)) { 1089 mei_hdr.length = mei_hbuf_max_len(dev); 1090 mei_hdr.msg_complete = 0; 1091 } else { 1092 mei_hdr.length = buf->size; 1093 mei_hdr.msg_complete = 1; 1094 } 1095 1096 rets = mei_write_message(dev, &mei_hdr, buf->data); 1097 if (rets) 1098 goto err; 1099 1100 cl->writing_state = MEI_WRITING; 1101 cb->buf_idx = mei_hdr.length; 1102 1103 out: 1104 if (mei_hdr.msg_complete) { 1105 rets = mei_cl_flow_ctrl_reduce(cl); 1106 if (rets < 0) 1107 goto err; 1108 1109 list_add_tail(&cb->list, &dev->write_waiting_list.list); 1110 } else { 1111 list_add_tail(&cb->list, &dev->write_list.list); 1112 } 1113 1114 1115 if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) { 1116 1117 mutex_unlock(&dev->device_lock); 1118 rets = wait_event_interruptible(cl->tx_wait, 1119 cl->writing_state == MEI_WRITE_COMPLETE); 1120 mutex_lock(&dev->device_lock); 1121 /* wait_event_interruptible returns -ERESTARTSYS */ 1122 if (rets) { 1123 if (signal_pending(current)) 1124 rets = -EINTR; 1125 goto err; 1126 } 1127 } 1128 1129 rets = buf->size; 1130 err: 1131 cl_dbg(dev, cl, "rpm: autosuspend\n"); 1132 pm_runtime_mark_last_busy(dev->dev); 1133 pm_runtime_put_autosuspend(dev->dev); 1134 1135 return rets; 1136 } 1137 1138 1139 /** 1140 * mei_cl_complete - processes completed operation for a client 1141 * 1142 * @cl: private data of the file object. 1143 * @cb: callback block. 1144 */ 1145 void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb) 1146 { 1147 if (cb->fop_type == MEI_FOP_WRITE) { 1148 mei_io_cb_free(cb); 1149 cb = NULL; 1150 cl->writing_state = MEI_WRITE_COMPLETE; 1151 if (waitqueue_active(&cl->tx_wait)) 1152 wake_up_interruptible(&cl->tx_wait); 1153 1154 } else if (cb->fop_type == MEI_FOP_READ && 1155 MEI_READING == cl->reading_state) { 1156 cl->reading_state = MEI_READ_COMPLETE; 1157 if (waitqueue_active(&cl->rx_wait)) 1158 wake_up_interruptible(&cl->rx_wait); 1159 else 1160 mei_cl_bus_rx_event(cl); 1161 1162 } 1163 } 1164 1165 1166 /** 1167 * mei_cl_all_disconnect - disconnect forcefully all connected clients 1168 * 1169 * @dev: mei device 1170 */ 1171 1172 void mei_cl_all_disconnect(struct mei_device *dev) 1173 { 1174 struct mei_cl *cl; 1175 1176 list_for_each_entry(cl, &dev->file_list, link) { 1177 cl->state = MEI_FILE_DISCONNECTED; 1178 cl->mei_flow_ctrl_creds = 0; 1179 cl->timer_count = 0; 1180 } 1181 } 1182 1183 1184 /** 1185 * mei_cl_all_wakeup - wake up all readers and writers they can be interrupted 1186 * 1187 * @dev: mei device 1188 */ 1189 void mei_cl_all_wakeup(struct mei_device *dev) 1190 { 1191 struct mei_cl *cl; 1192 1193 list_for_each_entry(cl, &dev->file_list, link) { 1194 if (waitqueue_active(&cl->rx_wait)) { 1195 cl_dbg(dev, cl, "Waking up reading client!\n"); 1196 wake_up_interruptible(&cl->rx_wait); 1197 } 1198 if (waitqueue_active(&cl->tx_wait)) { 1199 cl_dbg(dev, cl, "Waking up writing client!\n"); 1200 wake_up_interruptible(&cl->tx_wait); 1201 } 1202 } 1203 } 1204 1205 /** 1206 * mei_cl_all_write_clear - clear all pending writes 1207 * 1208 * @dev: mei device 1209 */ 1210 void mei_cl_all_write_clear(struct mei_device *dev) 1211 { 1212 mei_io_list_free(&dev->write_list, NULL); 1213 mei_io_list_free(&dev->write_waiting_list, NULL); 1214 } 1215 1216 1217