1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * ISHTP bus driver 4 * 5 * Copyright (c) 2012-2016, Intel Corporation. 6 */ 7 8 #include <linux/module.h> 9 #include <linux/init.h> 10 #include <linux/kernel.h> 11 #include <linux/device.h> 12 #include <linux/sched.h> 13 #include <linux/slab.h> 14 #include "bus.h" 15 #include "ishtp-dev.h" 16 #include "client.h" 17 #include "hbm.h" 18 19 static int ishtp_use_dma; 20 module_param_named(ishtp_use_dma, ishtp_use_dma, int, 0600); 21 MODULE_PARM_DESC(ishtp_use_dma, "Use DMA to send messages"); 22 23 #define to_ishtp_cl_driver(d) container_of(d, struct ishtp_cl_driver, driver) 24 #define to_ishtp_cl_device(d) container_of(d, struct ishtp_cl_device, dev) 25 static bool ishtp_device_ready; 26 27 /** 28 * ishtp_recv() - process ishtp message 29 * @dev: ishtp device 30 * 31 * If a message with valid header and size is received, then 32 * this function calls appropriate handler. The host or firmware 33 * address is zero, then they are host bus management message, 34 * otherwise they are message fo clients. 35 */ 36 void ishtp_recv(struct ishtp_device *dev) 37 { 38 uint32_t msg_hdr; 39 struct ishtp_msg_hdr *ishtp_hdr; 40 41 /* Read ISHTP header dword */ 42 msg_hdr = dev->ops->ishtp_read_hdr(dev); 43 if (!msg_hdr) 44 return; 45 46 dev->ops->sync_fw_clock(dev); 47 48 ishtp_hdr = (struct ishtp_msg_hdr *)&msg_hdr; 49 dev->ishtp_msg_hdr = msg_hdr; 50 51 /* Sanity check: ISHTP frag. length in header */ 52 if (ishtp_hdr->length > dev->mtu) { 53 dev_err(dev->devc, 54 "ISHTP hdr - bad length: %u; dropped [%08X]\n", 55 (unsigned int)ishtp_hdr->length, msg_hdr); 56 return; 57 } 58 59 /* ISHTP bus message */ 60 if (!ishtp_hdr->host_addr && !ishtp_hdr->fw_addr) 61 recv_hbm(dev, ishtp_hdr); 62 /* ISHTP fixed-client message */ 63 else if (!ishtp_hdr->host_addr) 64 recv_fixed_cl_msg(dev, ishtp_hdr); 65 else 66 /* ISHTP client message */ 67 recv_ishtp_cl_msg(dev, ishtp_hdr); 68 } 69 EXPORT_SYMBOL(ishtp_recv); 70 71 /** 72 * ishtp_send_msg() - Send ishtp message 73 * @dev: ishtp device 74 * @hdr: Message header 75 * @msg: Message contents 76 * @ipc_send_compl: completion callback 77 * @ipc_send_compl_prm: completion callback parameter 78 * 79 * Send a multi fragment message via IPC. After sending the first fragment 80 * the completion callback is called to schedule transmit of next fragment. 81 * 82 * Return: This returns IPC send message status. 83 */ 84 int ishtp_send_msg(struct ishtp_device *dev, struct ishtp_msg_hdr *hdr, 85 void *msg, void(*ipc_send_compl)(void *), 86 void *ipc_send_compl_prm) 87 { 88 unsigned char ipc_msg[IPC_FULL_MSG_SIZE]; 89 uint32_t drbl_val; 90 91 drbl_val = dev->ops->ipc_get_header(dev, hdr->length + 92 sizeof(struct ishtp_msg_hdr), 93 1); 94 95 memcpy(ipc_msg, &drbl_val, sizeof(uint32_t)); 96 memcpy(ipc_msg + sizeof(uint32_t), hdr, sizeof(uint32_t)); 97 memcpy(ipc_msg + 2 * sizeof(uint32_t), msg, hdr->length); 98 return dev->ops->write(dev, ipc_send_compl, ipc_send_compl_prm, 99 ipc_msg, 2 * sizeof(uint32_t) + hdr->length); 100 } 101 102 /** 103 * ishtp_write_message() - Send ishtp single fragment message 104 * @dev: ishtp device 105 * @hdr: Message header 106 * @buf: message data 107 * 108 * Send a single fragment message via IPC. This returns IPC send message 109 * status. 110 * 111 * Return: This returns IPC send message status. 112 */ 113 int ishtp_write_message(struct ishtp_device *dev, struct ishtp_msg_hdr *hdr, 114 void *buf) 115 { 116 return ishtp_send_msg(dev, hdr, buf, NULL, NULL); 117 } 118 119 /** 120 * ishtp_fw_cl_by_uuid() - locate index of fw client 121 * @dev: ishtp device 122 * @uuid: uuid of the client to search 123 * 124 * Search firmware client using UUID. 125 * 126 * Return: fw client index or -ENOENT if not found 127 */ 128 int ishtp_fw_cl_by_uuid(struct ishtp_device *dev, const guid_t *uuid) 129 { 130 unsigned int i; 131 132 for (i = 0; i < dev->fw_clients_num; ++i) { 133 if (guid_equal(uuid, &dev->fw_clients[i].props.protocol_name)) 134 return i; 135 } 136 return -ENOENT; 137 } 138 EXPORT_SYMBOL(ishtp_fw_cl_by_uuid); 139 140 /** 141 * ishtp_fw_cl_get_client() - return client information to client 142 * @dev: the ishtp device structure 143 * @uuid: uuid of the client to search 144 * 145 * Search firmware client using UUID and reture related client information. 146 * 147 * Return: pointer of client information on success, NULL on failure. 148 */ 149 struct ishtp_fw_client *ishtp_fw_cl_get_client(struct ishtp_device *dev, 150 const guid_t *uuid) 151 { 152 int i; 153 unsigned long flags; 154 155 spin_lock_irqsave(&dev->fw_clients_lock, flags); 156 i = ishtp_fw_cl_by_uuid(dev, uuid); 157 spin_unlock_irqrestore(&dev->fw_clients_lock, flags); 158 if (i < 0 || dev->fw_clients[i].props.fixed_address) 159 return NULL; 160 161 return &dev->fw_clients[i]; 162 } 163 EXPORT_SYMBOL(ishtp_fw_cl_get_client); 164 165 /** 166 * ishtp_get_fw_client_id() - Get fw client id 167 * 168 * This interface is used to reset HW get FW client id. 169 * 170 * Return: firmware client id. 171 */ 172 int ishtp_get_fw_client_id(struct ishtp_fw_client *fw_client) 173 { 174 return fw_client->client_id; 175 } 176 EXPORT_SYMBOL(ishtp_get_fw_client_id); 177 178 /** 179 * ishtp_fw_cl_by_id() - return index to fw_clients for client_id 180 * @dev: the ishtp device structure 181 * @client_id: fw client id to search 182 * 183 * Search firmware client using client id. 184 * 185 * Return: index on success, -ENOENT on failure. 186 */ 187 int ishtp_fw_cl_by_id(struct ishtp_device *dev, uint8_t client_id) 188 { 189 int i, res = -ENOENT; 190 unsigned long flags; 191 192 spin_lock_irqsave(&dev->fw_clients_lock, flags); 193 for (i = 0; i < dev->fw_clients_num; i++) { 194 if (dev->fw_clients[i].client_id == client_id) { 195 res = i; 196 break; 197 } 198 } 199 spin_unlock_irqrestore(&dev->fw_clients_lock, flags); 200 201 return res; 202 } 203 204 /** 205 * ishtp_cl_device_probe() - Bus probe() callback 206 * @dev: the device structure 207 * 208 * This is a bus probe callback and calls the drive probe function. 209 * 210 * Return: Return value from driver probe() call. 211 */ 212 static int ishtp_cl_device_probe(struct device *dev) 213 { 214 struct ishtp_cl_device *device = to_ishtp_cl_device(dev); 215 struct ishtp_cl_driver *driver; 216 217 if (!device) 218 return 0; 219 220 driver = to_ishtp_cl_driver(dev->driver); 221 if (!driver || !driver->probe) 222 return -ENODEV; 223 224 return driver->probe(device); 225 } 226 227 /** 228 * ishtp_cl_bus_match() - Bus match() callback 229 * @dev: the device structure 230 * @drv: the driver structure 231 * 232 * This is a bus match callback, called when a new ishtp_cl_device is 233 * registered during ishtp bus client enumeration. Use the guid_t in 234 * drv and dev to decide whether they match or not. 235 * 236 * Return: 1 if dev & drv matches, 0 otherwise. 237 */ 238 static int ishtp_cl_bus_match(struct device *dev, struct device_driver *drv) 239 { 240 struct ishtp_cl_device *device = to_ishtp_cl_device(dev); 241 struct ishtp_cl_driver *driver = to_ishtp_cl_driver(drv); 242 243 return guid_equal(driver->guid, 244 &device->fw_client->props.protocol_name); 245 } 246 247 /** 248 * ishtp_cl_device_remove() - Bus remove() callback 249 * @dev: the device structure 250 * 251 * This is a bus remove callback and calls the drive remove function. 252 * Since the ISH driver model supports only built in, this is 253 * primarily can be called during pci driver init failure. 254 * 255 * Return: Return value from driver remove() call. 256 */ 257 static int ishtp_cl_device_remove(struct device *dev) 258 { 259 struct ishtp_cl_device *device = to_ishtp_cl_device(dev); 260 struct ishtp_cl_driver *driver; 261 262 if (!device || !dev->driver) 263 return 0; 264 265 if (device->event_cb) { 266 device->event_cb = NULL; 267 cancel_work_sync(&device->event_work); 268 } 269 270 driver = to_ishtp_cl_driver(dev->driver); 271 if (!driver->remove) { 272 dev->driver = NULL; 273 274 return 0; 275 } 276 277 return driver->remove(device); 278 } 279 280 /** 281 * ishtp_cl_device_suspend() - Bus suspend callback 282 * @dev: device 283 * 284 * Called during device suspend process. 285 * 286 * Return: Return value from driver suspend() call. 287 */ 288 static int ishtp_cl_device_suspend(struct device *dev) 289 { 290 struct ishtp_cl_device *device = to_ishtp_cl_device(dev); 291 struct ishtp_cl_driver *driver; 292 int ret = 0; 293 294 if (!device) 295 return 0; 296 297 driver = to_ishtp_cl_driver(dev->driver); 298 if (driver && driver->driver.pm) { 299 if (driver->driver.pm->suspend) 300 ret = driver->driver.pm->suspend(dev); 301 } 302 303 return ret; 304 } 305 306 /** 307 * ishtp_cl_device_resume() - Bus resume callback 308 * @dev: device 309 * 310 * Called during device resume process. 311 * 312 * Return: Return value from driver resume() call. 313 */ 314 static int ishtp_cl_device_resume(struct device *dev) 315 { 316 struct ishtp_cl_device *device = to_ishtp_cl_device(dev); 317 struct ishtp_cl_driver *driver; 318 int ret = 0; 319 320 if (!device) 321 return 0; 322 323 /* 324 * When ISH needs hard reset, it is done asynchrnously, hence bus 325 * resume will be called before full ISH resume 326 */ 327 if (device->ishtp_dev->resume_flag) 328 return 0; 329 330 driver = to_ishtp_cl_driver(dev->driver); 331 if (driver && driver->driver.pm) { 332 if (driver->driver.pm->resume) 333 ret = driver->driver.pm->resume(dev); 334 } 335 336 return ret; 337 } 338 339 /** 340 * ishtp_cl_device_reset() - Reset callback 341 * @device: ishtp client device instance 342 * 343 * This is a callback when HW reset is done and the device need 344 * reinit. 345 * 346 * Return: Return value from driver reset() call. 347 */ 348 static int ishtp_cl_device_reset(struct ishtp_cl_device *device) 349 { 350 struct ishtp_cl_driver *driver; 351 int ret = 0; 352 353 device->event_cb = NULL; 354 cancel_work_sync(&device->event_work); 355 356 driver = to_ishtp_cl_driver(device->dev.driver); 357 if (driver && driver->reset) 358 ret = driver->reset(device); 359 360 return ret; 361 } 362 363 static ssize_t modalias_show(struct device *dev, struct device_attribute *a, 364 char *buf) 365 { 366 int len; 367 368 len = snprintf(buf, PAGE_SIZE, "ishtp:%s\n", dev_name(dev)); 369 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len; 370 } 371 static DEVICE_ATTR_RO(modalias); 372 373 static struct attribute *ishtp_cl_dev_attrs[] = { 374 &dev_attr_modalias.attr, 375 NULL, 376 }; 377 ATTRIBUTE_GROUPS(ishtp_cl_dev); 378 379 static int ishtp_cl_uevent(struct device *dev, struct kobj_uevent_env *env) 380 { 381 if (add_uevent_var(env, "MODALIAS=ishtp:%s", dev_name(dev))) 382 return -ENOMEM; 383 return 0; 384 } 385 386 static const struct dev_pm_ops ishtp_cl_bus_dev_pm_ops = { 387 /* Suspend callbacks */ 388 .suspend = ishtp_cl_device_suspend, 389 .resume = ishtp_cl_device_resume, 390 /* Hibernate callbacks */ 391 .freeze = ishtp_cl_device_suspend, 392 .thaw = ishtp_cl_device_resume, 393 .restore = ishtp_cl_device_resume, 394 }; 395 396 static struct bus_type ishtp_cl_bus_type = { 397 .name = "ishtp", 398 .dev_groups = ishtp_cl_dev_groups, 399 .probe = ishtp_cl_device_probe, 400 .match = ishtp_cl_bus_match, 401 .remove = ishtp_cl_device_remove, 402 .pm = &ishtp_cl_bus_dev_pm_ops, 403 .uevent = ishtp_cl_uevent, 404 }; 405 406 static void ishtp_cl_dev_release(struct device *dev) 407 { 408 kfree(to_ishtp_cl_device(dev)); 409 } 410 411 static const struct device_type ishtp_cl_device_type = { 412 .release = ishtp_cl_dev_release, 413 }; 414 415 /** 416 * ishtp_bus_add_device() - Function to create device on bus 417 * @dev: ishtp device 418 * @uuid: uuid of the client 419 * @name: Name of the client 420 * 421 * Allocate ISHTP bus client device, attach it to uuid 422 * and register with ISHTP bus. 423 * 424 * Return: ishtp_cl_device pointer or NULL on failure 425 */ 426 static struct ishtp_cl_device *ishtp_bus_add_device(struct ishtp_device *dev, 427 guid_t uuid, char *name) 428 { 429 struct ishtp_cl_device *device; 430 int status; 431 unsigned long flags; 432 433 spin_lock_irqsave(&dev->device_list_lock, flags); 434 list_for_each_entry(device, &dev->device_list, device_link) { 435 if (!strcmp(name, dev_name(&device->dev))) { 436 device->fw_client = &dev->fw_clients[ 437 dev->fw_client_presentation_num - 1]; 438 spin_unlock_irqrestore(&dev->device_list_lock, flags); 439 ishtp_cl_device_reset(device); 440 return device; 441 } 442 } 443 spin_unlock_irqrestore(&dev->device_list_lock, flags); 444 445 device = kzalloc(sizeof(struct ishtp_cl_device), GFP_KERNEL); 446 if (!device) 447 return NULL; 448 449 device->dev.parent = dev->devc; 450 device->dev.bus = &ishtp_cl_bus_type; 451 device->dev.type = &ishtp_cl_device_type; 452 device->ishtp_dev = dev; 453 454 device->fw_client = 455 &dev->fw_clients[dev->fw_client_presentation_num - 1]; 456 457 dev_set_name(&device->dev, "%s", name); 458 459 spin_lock_irqsave(&dev->device_list_lock, flags); 460 list_add_tail(&device->device_link, &dev->device_list); 461 spin_unlock_irqrestore(&dev->device_list_lock, flags); 462 463 status = device_register(&device->dev); 464 if (status) { 465 spin_lock_irqsave(&dev->device_list_lock, flags); 466 list_del(&device->device_link); 467 spin_unlock_irqrestore(&dev->device_list_lock, flags); 468 dev_err(dev->devc, "Failed to register ISHTP client device\n"); 469 put_device(&device->dev); 470 return NULL; 471 } 472 473 ishtp_device_ready = true; 474 475 return device; 476 } 477 478 /** 479 * ishtp_bus_remove_device() - Function to relase device on bus 480 * @device: client device instance 481 * 482 * This is a counterpart of ishtp_bus_add_device. 483 * Device is unregistered. 484 * the device structure is freed in 'ishtp_cl_dev_release' function 485 * Called only during error in pci driver init path. 486 */ 487 static void ishtp_bus_remove_device(struct ishtp_cl_device *device) 488 { 489 device_unregister(&device->dev); 490 } 491 492 /** 493 * ishtp_cl_driver_register() - Client driver register 494 * @driver: the client driver instance 495 * @owner: Owner of this driver module 496 * 497 * Once a client driver is probed, it created a client 498 * instance and registers with the bus. 499 * 500 * Return: Return value of driver_register or -ENODEV if not ready 501 */ 502 int ishtp_cl_driver_register(struct ishtp_cl_driver *driver, 503 struct module *owner) 504 { 505 if (!ishtp_device_ready) 506 return -ENODEV; 507 508 driver->driver.name = driver->name; 509 driver->driver.owner = owner; 510 driver->driver.bus = &ishtp_cl_bus_type; 511 512 return driver_register(&driver->driver); 513 } 514 EXPORT_SYMBOL(ishtp_cl_driver_register); 515 516 /** 517 * ishtp_cl_driver_unregister() - Client driver unregister 518 * @driver: the client driver instance 519 * 520 * Unregister client during device removal process. 521 */ 522 void ishtp_cl_driver_unregister(struct ishtp_cl_driver *driver) 523 { 524 driver_unregister(&driver->driver); 525 } 526 EXPORT_SYMBOL(ishtp_cl_driver_unregister); 527 528 /** 529 * ishtp_bus_event_work() - event work function 530 * @work: work struct pointer 531 * 532 * Once an event is received for a client this work 533 * function is called. If the device has registered a 534 * callback then the callback is called. 535 */ 536 static void ishtp_bus_event_work(struct work_struct *work) 537 { 538 struct ishtp_cl_device *device; 539 540 device = container_of(work, struct ishtp_cl_device, event_work); 541 542 if (device->event_cb) 543 device->event_cb(device); 544 } 545 546 /** 547 * ishtp_cl_bus_rx_event() - schedule event work 548 * @device: client device instance 549 * 550 * Once an event is received for a client this schedules 551 * a work function to process. 552 */ 553 void ishtp_cl_bus_rx_event(struct ishtp_cl_device *device) 554 { 555 if (!device || !device->event_cb) 556 return; 557 558 if (device->event_cb) 559 schedule_work(&device->event_work); 560 } 561 562 /** 563 * ishtp_register_event_cb() - Register callback 564 * @device: client device instance 565 * @event_cb: Event processor for an client 566 * 567 * Register a callback for events, called from client driver 568 * 569 * Return: Return 0 or -EALREADY if already registered 570 */ 571 int ishtp_register_event_cb(struct ishtp_cl_device *device, 572 void (*event_cb)(struct ishtp_cl_device *)) 573 { 574 if (device->event_cb) 575 return -EALREADY; 576 577 device->event_cb = event_cb; 578 INIT_WORK(&device->event_work, ishtp_bus_event_work); 579 580 return 0; 581 } 582 EXPORT_SYMBOL(ishtp_register_event_cb); 583 584 /** 585 * ishtp_get_device() - update usage count for the device 586 * @cl_device: client device instance 587 * 588 * Increment the usage count. The device can't be deleted 589 */ 590 void ishtp_get_device(struct ishtp_cl_device *cl_device) 591 { 592 cl_device->reference_count++; 593 } 594 EXPORT_SYMBOL(ishtp_get_device); 595 596 /** 597 * ishtp_put_device() - decrement usage count for the device 598 * @cl_device: client device instance 599 * 600 * Decrement the usage count. The device can be deleted is count = 0 601 */ 602 void ishtp_put_device(struct ishtp_cl_device *cl_device) 603 { 604 cl_device->reference_count--; 605 } 606 EXPORT_SYMBOL(ishtp_put_device); 607 608 /** 609 * ishtp_set_drvdata() - set client driver data 610 * @cl_device: client device instance 611 * @data: driver data need to be set 612 * 613 * Set client driver data to cl_device->driver_data. 614 */ 615 void ishtp_set_drvdata(struct ishtp_cl_device *cl_device, void *data) 616 { 617 cl_device->driver_data = data; 618 } 619 EXPORT_SYMBOL(ishtp_set_drvdata); 620 621 /** 622 * ishtp_get_drvdata() - get client driver data 623 * @cl_device: client device instance 624 * 625 * Get client driver data from cl_device->driver_data. 626 * 627 * Return: pointer of driver data 628 */ 629 void *ishtp_get_drvdata(struct ishtp_cl_device *cl_device) 630 { 631 return cl_device->driver_data; 632 } 633 EXPORT_SYMBOL(ishtp_get_drvdata); 634 635 /** 636 * ishtp_dev_to_cl_device() - get ishtp_cl_device instance from device instance 637 * @device: device instance 638 * 639 * Get ish_cl_device instance which embeds device instance in it. 640 * 641 * Return: pointer to ishtp_cl_device instance 642 */ 643 struct ishtp_cl_device *ishtp_dev_to_cl_device(struct device *device) 644 { 645 return to_ishtp_cl_device(device); 646 } 647 EXPORT_SYMBOL(ishtp_dev_to_cl_device); 648 649 /** 650 * ishtp_bus_new_client() - Create a new client 651 * @dev: ISHTP device instance 652 * 653 * Once bus protocol enumerates a client, this is called 654 * to add a device for the client. 655 * 656 * Return: 0 on success or error code on failure 657 */ 658 int ishtp_bus_new_client(struct ishtp_device *dev) 659 { 660 int i; 661 char *dev_name; 662 struct ishtp_cl_device *cl_device; 663 guid_t device_uuid; 664 665 /* 666 * For all reported clients, create an unconnected client and add its 667 * device to ISHTP bus. 668 * If appropriate driver has loaded, this will trigger its probe(). 669 * Otherwise, probe() will be called when driver is loaded 670 */ 671 i = dev->fw_client_presentation_num - 1; 672 device_uuid = dev->fw_clients[i].props.protocol_name; 673 dev_name = kasprintf(GFP_KERNEL, "{%pUL}", &device_uuid); 674 if (!dev_name) 675 return -ENOMEM; 676 677 cl_device = ishtp_bus_add_device(dev, device_uuid, dev_name); 678 if (!cl_device) { 679 kfree(dev_name); 680 return -ENOENT; 681 } 682 683 kfree(dev_name); 684 685 return 0; 686 } 687 688 /** 689 * ishtp_cl_device_bind() - bind a device 690 * @cl: ishtp client device 691 * 692 * Binds connected ishtp_cl to ISHTP bus device 693 * 694 * Return: 0 on success or fault code 695 */ 696 int ishtp_cl_device_bind(struct ishtp_cl *cl) 697 { 698 struct ishtp_cl_device *cl_device; 699 unsigned long flags; 700 int rv; 701 702 if (!cl->fw_client_id || cl->state != ISHTP_CL_CONNECTED) 703 return -EFAULT; 704 705 rv = -ENOENT; 706 spin_lock_irqsave(&cl->dev->device_list_lock, flags); 707 list_for_each_entry(cl_device, &cl->dev->device_list, 708 device_link) { 709 if (cl_device->fw_client && 710 cl_device->fw_client->client_id == cl->fw_client_id) { 711 cl->device = cl_device; 712 rv = 0; 713 break; 714 } 715 } 716 spin_unlock_irqrestore(&cl->dev->device_list_lock, flags); 717 return rv; 718 } 719 720 /** 721 * ishtp_bus_remove_all_clients() - Remove all clients 722 * @ishtp_dev: ishtp device 723 * @warm_reset: Reset due to FW reset dure to errors or S3 suspend 724 * 725 * This is part of reset/remove flow. This function the main processing 726 * only targets error processing, if the FW has forced reset or 727 * error to remove connected clients. When warm reset the client devices are 728 * not removed. 729 */ 730 void ishtp_bus_remove_all_clients(struct ishtp_device *ishtp_dev, 731 bool warm_reset) 732 { 733 struct ishtp_cl_device *cl_device, *n; 734 struct ishtp_cl *cl; 735 unsigned long flags; 736 737 spin_lock_irqsave(&ishtp_dev->cl_list_lock, flags); 738 list_for_each_entry(cl, &ishtp_dev->cl_list, link) { 739 cl->state = ISHTP_CL_DISCONNECTED; 740 741 /* 742 * Wake any pending process. The waiter would check dev->state 743 * and determine that it's not enabled already, 744 * and will return error to its caller 745 */ 746 wake_up_interruptible(&cl->wait_ctrl_res); 747 748 /* Disband any pending read/write requests and free rb */ 749 ishtp_cl_flush_queues(cl); 750 751 /* Remove all free and in_process rings, both Rx and Tx */ 752 ishtp_cl_free_rx_ring(cl); 753 ishtp_cl_free_tx_ring(cl); 754 755 /* 756 * Free client and ISHTP bus client device structures 757 * don't free host client because it is part of the OS fd 758 * structure 759 */ 760 } 761 spin_unlock_irqrestore(&ishtp_dev->cl_list_lock, flags); 762 763 /* Release DMA buffers for client messages */ 764 ishtp_cl_free_dma_buf(ishtp_dev); 765 766 /* remove bus clients */ 767 spin_lock_irqsave(&ishtp_dev->device_list_lock, flags); 768 list_for_each_entry_safe(cl_device, n, &ishtp_dev->device_list, 769 device_link) { 770 cl_device->fw_client = NULL; 771 if (warm_reset && cl_device->reference_count) 772 continue; 773 774 list_del(&cl_device->device_link); 775 spin_unlock_irqrestore(&ishtp_dev->device_list_lock, flags); 776 ishtp_bus_remove_device(cl_device); 777 spin_lock_irqsave(&ishtp_dev->device_list_lock, flags); 778 } 779 spin_unlock_irqrestore(&ishtp_dev->device_list_lock, flags); 780 781 /* Free all client structures */ 782 spin_lock_irqsave(&ishtp_dev->fw_clients_lock, flags); 783 kfree(ishtp_dev->fw_clients); 784 ishtp_dev->fw_clients = NULL; 785 ishtp_dev->fw_clients_num = 0; 786 ishtp_dev->fw_client_presentation_num = 0; 787 ishtp_dev->fw_client_index = 0; 788 bitmap_zero(ishtp_dev->fw_clients_map, ISHTP_CLIENTS_MAX); 789 spin_unlock_irqrestore(&ishtp_dev->fw_clients_lock, flags); 790 } 791 EXPORT_SYMBOL(ishtp_bus_remove_all_clients); 792 793 /** 794 * ishtp_reset_handler() - IPC reset handler 795 * @dev: ishtp device 796 * 797 * ISHTP Handler for IPC_RESET notification 798 */ 799 void ishtp_reset_handler(struct ishtp_device *dev) 800 { 801 unsigned long flags; 802 803 /* Handle FW-initiated reset */ 804 dev->dev_state = ISHTP_DEV_RESETTING; 805 806 /* Clear BH processing queue - no further HBMs */ 807 spin_lock_irqsave(&dev->rd_msg_spinlock, flags); 808 dev->rd_msg_fifo_head = dev->rd_msg_fifo_tail = 0; 809 spin_unlock_irqrestore(&dev->rd_msg_spinlock, flags); 810 811 /* Handle ISH FW reset against upper layers */ 812 ishtp_bus_remove_all_clients(dev, true); 813 } 814 EXPORT_SYMBOL(ishtp_reset_handler); 815 816 /** 817 * ishtp_reset_compl_handler() - Reset completion handler 818 * @dev: ishtp device 819 * 820 * ISHTP handler for IPC_RESET sequence completion to start 821 * host message bus start protocol sequence. 822 */ 823 void ishtp_reset_compl_handler(struct ishtp_device *dev) 824 { 825 dev->dev_state = ISHTP_DEV_INIT_CLIENTS; 826 dev->hbm_state = ISHTP_HBM_START; 827 ishtp_hbm_start_req(dev); 828 } 829 EXPORT_SYMBOL(ishtp_reset_compl_handler); 830 831 /** 832 * ishtp_use_dma_transfer() - Function to use DMA 833 * 834 * This interface is used to enable usage of DMA 835 * 836 * Return non zero if DMA can be enabled 837 */ 838 int ishtp_use_dma_transfer(void) 839 { 840 return ishtp_use_dma; 841 } 842 843 /** 844 * ishtp_device() - Return device pointer 845 * 846 * This interface is used to return device pointer from ishtp_cl_device 847 * instance. 848 * 849 * Return: device *. 850 */ 851 struct device *ishtp_device(struct ishtp_cl_device *device) 852 { 853 return &device->dev; 854 } 855 EXPORT_SYMBOL(ishtp_device); 856 857 /** 858 * ishtp_get_pci_device() - Return PCI device dev pointer 859 * This interface is used to return PCI device pointer 860 * from ishtp_cl_device instance. 861 * 862 * Return: device *. 863 */ 864 struct device *ishtp_get_pci_device(struct ishtp_cl_device *device) 865 { 866 return device->ishtp_dev->devc; 867 } 868 EXPORT_SYMBOL(ishtp_get_pci_device); 869 870 /** 871 * ishtp_trace_callback() - Return trace callback 872 * 873 * This interface is used to return trace callback function pointer. 874 * 875 * Return: void *. 876 */ 877 void *ishtp_trace_callback(struct ishtp_cl_device *cl_device) 878 { 879 return cl_device->ishtp_dev->print_log; 880 } 881 EXPORT_SYMBOL(ishtp_trace_callback); 882 883 /** 884 * ish_hw_reset() - Call HW reset IPC callback 885 * 886 * This interface is used to reset HW in case of error. 887 * 888 * Return: value from IPC hw_reset callback 889 */ 890 int ish_hw_reset(struct ishtp_device *dev) 891 { 892 return dev->ops->hw_reset(dev); 893 } 894 EXPORT_SYMBOL(ish_hw_reset); 895 896 /** 897 * ishtp_bus_register() - Function to register bus 898 * 899 * This register ishtp bus 900 * 901 * Return: Return output of bus_register 902 */ 903 static int __init ishtp_bus_register(void) 904 { 905 return bus_register(&ishtp_cl_bus_type); 906 } 907 908 /** 909 * ishtp_bus_unregister() - Function to unregister bus 910 * 911 * This unregister ishtp bus 912 */ 913 static void __exit ishtp_bus_unregister(void) 914 { 915 bus_unregister(&ishtp_cl_bus_type); 916 } 917 918 module_init(ishtp_bus_register); 919 module_exit(ishtp_bus_unregister); 920 921 MODULE_LICENSE("GPL"); 922