1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2012-2019, Intel Corporation. All rights reserved. 4 * Intel Management Engine Interface (Intel MEI) Linux driver 5 */ 6 7 #include <linux/module.h> 8 #include <linux/device.h> 9 #include <linux/kernel.h> 10 #include <linux/sched/signal.h> 11 #include <linux/init.h> 12 #include <linux/errno.h> 13 #include <linux/slab.h> 14 #include <linux/mutex.h> 15 #include <linux/interrupt.h> 16 #include <linux/mei_cl_bus.h> 17 18 #include "mei_dev.h" 19 #include "client.h" 20 21 #define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver) 22 23 /** 24 * __mei_cl_send - internal client send (write) 25 * 26 * @cl: host client 27 * @buf: buffer to send 28 * @length: buffer length 29 * @mode: sending mode 30 * 31 * Return: written size bytes or < 0 on error 32 */ 33 ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length, 34 unsigned int mode) 35 { 36 struct mei_device *bus; 37 struct mei_cl_cb *cb; 38 ssize_t rets; 39 40 if (WARN_ON(!cl || !cl->dev)) 41 return -ENODEV; 42 43 bus = cl->dev; 44 45 mutex_lock(&bus->device_lock); 46 if (bus->dev_state != MEI_DEV_ENABLED) { 47 rets = -ENODEV; 48 goto out; 49 } 50 51 if (!mei_cl_is_connected(cl)) { 52 rets = -ENODEV; 53 goto out; 54 } 55 56 /* Check if we have an ME client device */ 57 if (!mei_me_cl_is_active(cl->me_cl)) { 58 rets = -ENOTTY; 59 goto out; 60 } 61 62 if (length > mei_cl_mtu(cl)) { 63 rets = -EFBIG; 64 goto out; 65 } 66 67 while (cl->tx_cb_queued >= bus->tx_queue_limit) { 68 mutex_unlock(&bus->device_lock); 69 rets = wait_event_interruptible(cl->tx_wait, 70 cl->writing_state == MEI_WRITE_COMPLETE || 71 (!mei_cl_is_connected(cl))); 72 mutex_lock(&bus->device_lock); 73 if (rets) { 74 if (signal_pending(current)) 75 rets = -EINTR; 76 goto out; 77 } 78 if (!mei_cl_is_connected(cl)) { 79 rets = -ENODEV; 80 goto out; 81 } 82 } 83 84 cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, NULL); 85 if (!cb) { 86 rets = -ENOMEM; 87 goto out; 88 } 89 90 cb->internal = !!(mode & MEI_CL_IO_TX_INTERNAL); 91 cb->blocking = !!(mode & MEI_CL_IO_TX_BLOCKING); 92 memcpy(cb->buf.data, buf, length); 93 94 rets = mei_cl_write(cl, cb); 95 96 out: 97 mutex_unlock(&bus->device_lock); 98 99 return rets; 100 } 101 102 /** 103 * __mei_cl_recv - internal client receive (read) 104 * 105 * @cl: host client 106 * @buf: buffer to receive 107 * @length: buffer length 108 * @mode: io mode 109 * @timeout: recv timeout, 0 for infinite timeout 110 * 111 * Return: read size in bytes of < 0 on error 112 */ 113 ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length, 114 unsigned int mode, unsigned long timeout) 115 { 116 struct mei_device *bus; 117 struct mei_cl_cb *cb; 118 size_t r_length; 119 ssize_t rets; 120 bool nonblock = !!(mode & MEI_CL_IO_RX_NONBLOCK); 121 122 if (WARN_ON(!cl || !cl->dev)) 123 return -ENODEV; 124 125 bus = cl->dev; 126 127 mutex_lock(&bus->device_lock); 128 if (bus->dev_state != MEI_DEV_ENABLED) { 129 rets = -ENODEV; 130 goto out; 131 } 132 133 cb = mei_cl_read_cb(cl, NULL); 134 if (cb) 135 goto copy; 136 137 rets = mei_cl_read_start(cl, length, NULL); 138 if (rets && rets != -EBUSY) 139 goto out; 140 141 if (nonblock) { 142 rets = -EAGAIN; 143 goto out; 144 } 145 146 /* wait on event only if there is no other waiter */ 147 /* synchronized under device mutex */ 148 if (!waitqueue_active(&cl->rx_wait)) { 149 150 mutex_unlock(&bus->device_lock); 151 152 if (timeout) { 153 rets = wait_event_interruptible_timeout 154 (cl->rx_wait, 155 (!list_empty(&cl->rd_completed)) || 156 (!mei_cl_is_connected(cl)), 157 msecs_to_jiffies(timeout)); 158 if (rets == 0) 159 return -ETIME; 160 if (rets < 0) { 161 if (signal_pending(current)) 162 return -EINTR; 163 return -ERESTARTSYS; 164 } 165 } else { 166 if (wait_event_interruptible 167 (cl->rx_wait, 168 (!list_empty(&cl->rd_completed)) || 169 (!mei_cl_is_connected(cl)))) { 170 if (signal_pending(current)) 171 return -EINTR; 172 return -ERESTARTSYS; 173 } 174 } 175 176 mutex_lock(&bus->device_lock); 177 178 if (!mei_cl_is_connected(cl)) { 179 rets = -ENODEV; 180 goto out; 181 } 182 } 183 184 cb = mei_cl_read_cb(cl, NULL); 185 if (!cb) { 186 rets = 0; 187 goto out; 188 } 189 190 copy: 191 if (cb->status) { 192 rets = cb->status; 193 goto free; 194 } 195 196 r_length = min_t(size_t, length, cb->buf_idx); 197 memcpy(buf, cb->buf.data, r_length); 198 rets = r_length; 199 200 free: 201 mei_io_cb_free(cb); 202 out: 203 mutex_unlock(&bus->device_lock); 204 205 return rets; 206 } 207 208 /** 209 * mei_cldev_send - me device send (write) 210 * 211 * @cldev: me client device 212 * @buf: buffer to send 213 * @length: buffer length 214 * 215 * Return: written size in bytes or < 0 on error 216 */ 217 ssize_t mei_cldev_send(struct mei_cl_device *cldev, u8 *buf, size_t length) 218 { 219 struct mei_cl *cl = cldev->cl; 220 221 return __mei_cl_send(cl, buf, length, MEI_CL_IO_TX_BLOCKING); 222 } 223 EXPORT_SYMBOL_GPL(mei_cldev_send); 224 225 /** 226 * mei_cldev_recv_nonblock - non block client receive (read) 227 * 228 * @cldev: me client device 229 * @buf: buffer to receive 230 * @length: buffer length 231 * 232 * Return: read size in bytes of < 0 on error 233 * -EAGAIN if function will block. 234 */ 235 ssize_t mei_cldev_recv_nonblock(struct mei_cl_device *cldev, u8 *buf, 236 size_t length) 237 { 238 struct mei_cl *cl = cldev->cl; 239 240 return __mei_cl_recv(cl, buf, length, MEI_CL_IO_RX_NONBLOCK, 0); 241 } 242 EXPORT_SYMBOL_GPL(mei_cldev_recv_nonblock); 243 244 /** 245 * mei_cldev_recv - client receive (read) 246 * 247 * @cldev: me client device 248 * @buf: buffer to receive 249 * @length: buffer length 250 * 251 * Return: read size in bytes of < 0 on error 252 */ 253 ssize_t mei_cldev_recv(struct mei_cl_device *cldev, u8 *buf, size_t length) 254 { 255 struct mei_cl *cl = cldev->cl; 256 257 return __mei_cl_recv(cl, buf, length, 0, 0); 258 } 259 EXPORT_SYMBOL_GPL(mei_cldev_recv); 260 261 /** 262 * mei_cl_bus_rx_work - dispatch rx event for a bus device 263 * 264 * @work: work 265 */ 266 static void mei_cl_bus_rx_work(struct work_struct *work) 267 { 268 struct mei_cl_device *cldev; 269 struct mei_device *bus; 270 271 cldev = container_of(work, struct mei_cl_device, rx_work); 272 273 bus = cldev->bus; 274 275 if (cldev->rx_cb) 276 cldev->rx_cb(cldev); 277 278 mutex_lock(&bus->device_lock); 279 mei_cl_read_start(cldev->cl, mei_cl_mtu(cldev->cl), NULL); 280 mutex_unlock(&bus->device_lock); 281 } 282 283 /** 284 * mei_cl_bus_notif_work - dispatch FW notif event for a bus device 285 * 286 * @work: work 287 */ 288 static void mei_cl_bus_notif_work(struct work_struct *work) 289 { 290 struct mei_cl_device *cldev; 291 292 cldev = container_of(work, struct mei_cl_device, notif_work); 293 294 if (cldev->notif_cb) 295 cldev->notif_cb(cldev); 296 } 297 298 /** 299 * mei_cl_bus_notify_event - schedule notify cb on bus client 300 * 301 * @cl: host client 302 * 303 * Return: true if event was scheduled 304 * false if the client is not waiting for event 305 */ 306 bool mei_cl_bus_notify_event(struct mei_cl *cl) 307 { 308 struct mei_cl_device *cldev = cl->cldev; 309 310 if (!cldev || !cldev->notif_cb) 311 return false; 312 313 if (!cl->notify_ev) 314 return false; 315 316 schedule_work(&cldev->notif_work); 317 318 cl->notify_ev = false; 319 320 return true; 321 } 322 323 /** 324 * mei_cl_bus_rx_event - schedule rx event 325 * 326 * @cl: host client 327 * 328 * Return: true if event was scheduled 329 * false if the client is not waiting for event 330 */ 331 bool mei_cl_bus_rx_event(struct mei_cl *cl) 332 { 333 struct mei_cl_device *cldev = cl->cldev; 334 335 if (!cldev || !cldev->rx_cb) 336 return false; 337 338 schedule_work(&cldev->rx_work); 339 340 return true; 341 } 342 343 /** 344 * mei_cldev_register_rx_cb - register Rx event callback 345 * 346 * @cldev: me client devices 347 * @rx_cb: callback function 348 * 349 * Return: 0 on success 350 * -EALREADY if an callback is already registered 351 * <0 on other errors 352 */ 353 int mei_cldev_register_rx_cb(struct mei_cl_device *cldev, mei_cldev_cb_t rx_cb) 354 { 355 struct mei_device *bus = cldev->bus; 356 int ret; 357 358 if (!rx_cb) 359 return -EINVAL; 360 if (cldev->rx_cb) 361 return -EALREADY; 362 363 cldev->rx_cb = rx_cb; 364 INIT_WORK(&cldev->rx_work, mei_cl_bus_rx_work); 365 366 mutex_lock(&bus->device_lock); 367 ret = mei_cl_read_start(cldev->cl, mei_cl_mtu(cldev->cl), NULL); 368 mutex_unlock(&bus->device_lock); 369 if (ret && ret != -EBUSY) 370 return ret; 371 372 return 0; 373 } 374 EXPORT_SYMBOL_GPL(mei_cldev_register_rx_cb); 375 376 /** 377 * mei_cldev_register_notif_cb - register FW notification event callback 378 * 379 * @cldev: me client devices 380 * @notif_cb: callback function 381 * 382 * Return: 0 on success 383 * -EALREADY if an callback is already registered 384 * <0 on other errors 385 */ 386 int mei_cldev_register_notif_cb(struct mei_cl_device *cldev, 387 mei_cldev_cb_t notif_cb) 388 { 389 struct mei_device *bus = cldev->bus; 390 int ret; 391 392 if (!notif_cb) 393 return -EINVAL; 394 395 if (cldev->notif_cb) 396 return -EALREADY; 397 398 cldev->notif_cb = notif_cb; 399 INIT_WORK(&cldev->notif_work, mei_cl_bus_notif_work); 400 401 mutex_lock(&bus->device_lock); 402 ret = mei_cl_notify_request(cldev->cl, NULL, 1); 403 mutex_unlock(&bus->device_lock); 404 if (ret) 405 return ret; 406 407 return 0; 408 } 409 EXPORT_SYMBOL_GPL(mei_cldev_register_notif_cb); 410 411 /** 412 * mei_cldev_get_drvdata - driver data getter 413 * 414 * @cldev: mei client device 415 * 416 * Return: driver private data 417 */ 418 void *mei_cldev_get_drvdata(const struct mei_cl_device *cldev) 419 { 420 return dev_get_drvdata(&cldev->dev); 421 } 422 EXPORT_SYMBOL_GPL(mei_cldev_get_drvdata); 423 424 /** 425 * mei_cldev_set_drvdata - driver data setter 426 * 427 * @cldev: mei client device 428 * @data: data to store 429 */ 430 void mei_cldev_set_drvdata(struct mei_cl_device *cldev, void *data) 431 { 432 dev_set_drvdata(&cldev->dev, data); 433 } 434 EXPORT_SYMBOL_GPL(mei_cldev_set_drvdata); 435 436 /** 437 * mei_cldev_uuid - return uuid of the underlying me client 438 * 439 * @cldev: mei client device 440 * 441 * Return: me client uuid 442 */ 443 const uuid_le *mei_cldev_uuid(const struct mei_cl_device *cldev) 444 { 445 return mei_me_cl_uuid(cldev->me_cl); 446 } 447 EXPORT_SYMBOL_GPL(mei_cldev_uuid); 448 449 /** 450 * mei_cldev_ver - return protocol version of the underlying me client 451 * 452 * @cldev: mei client device 453 * 454 * Return: me client protocol version 455 */ 456 u8 mei_cldev_ver(const struct mei_cl_device *cldev) 457 { 458 return mei_me_cl_ver(cldev->me_cl); 459 } 460 EXPORT_SYMBOL_GPL(mei_cldev_ver); 461 462 /** 463 * mei_cldev_enabled - check whether the device is enabled 464 * 465 * @cldev: mei client device 466 * 467 * Return: true if me client is initialized and connected 468 */ 469 bool mei_cldev_enabled(struct mei_cl_device *cldev) 470 { 471 return mei_cl_is_connected(cldev->cl); 472 } 473 EXPORT_SYMBOL_GPL(mei_cldev_enabled); 474 475 /** 476 * mei_cl_bus_module_get - acquire module of the underlying 477 * hw driver. 478 * 479 * @cldev: mei client device 480 * 481 * Return: true on success; false if the module was removed. 482 */ 483 static bool mei_cl_bus_module_get(struct mei_cl_device *cldev) 484 { 485 return try_module_get(cldev->bus->dev->driver->owner); 486 } 487 488 /** 489 * mei_cl_bus_module_put - release the underlying hw module. 490 * 491 * @cldev: mei client device 492 */ 493 static void mei_cl_bus_module_put(struct mei_cl_device *cldev) 494 { 495 module_put(cldev->bus->dev->driver->owner); 496 } 497 498 /** 499 * mei_cldev_enable - enable me client device 500 * create connection with me client 501 * 502 * @cldev: me client device 503 * 504 * Return: 0 on success and < 0 on error 505 */ 506 int mei_cldev_enable(struct mei_cl_device *cldev) 507 { 508 struct mei_device *bus = cldev->bus; 509 struct mei_cl *cl; 510 int ret; 511 512 cl = cldev->cl; 513 514 mutex_lock(&bus->device_lock); 515 if (cl->state == MEI_FILE_UNINITIALIZED) { 516 ret = mei_cl_link(cl); 517 if (ret) 518 goto out; 519 /* update pointers */ 520 cl->cldev = cldev; 521 } 522 523 if (mei_cl_is_connected(cl)) { 524 ret = 0; 525 goto out; 526 } 527 528 if (!mei_me_cl_is_active(cldev->me_cl)) { 529 dev_err(&cldev->dev, "me client is not active\n"); 530 ret = -ENOTTY; 531 goto out; 532 } 533 534 ret = mei_cl_connect(cl, cldev->me_cl, NULL); 535 if (ret < 0) 536 dev_err(&cldev->dev, "cannot connect\n"); 537 538 out: 539 mutex_unlock(&bus->device_lock); 540 541 return ret; 542 } 543 EXPORT_SYMBOL_GPL(mei_cldev_enable); 544 545 /** 546 * mei_cldev_unregister_callbacks - internal wrapper for unregistering 547 * callbacks. 548 * 549 * @cldev: client device 550 */ 551 static void mei_cldev_unregister_callbacks(struct mei_cl_device *cldev) 552 { 553 if (cldev->rx_cb) { 554 cancel_work_sync(&cldev->rx_work); 555 cldev->rx_cb = NULL; 556 } 557 558 if (cldev->notif_cb) { 559 cancel_work_sync(&cldev->notif_work); 560 cldev->notif_cb = NULL; 561 } 562 } 563 564 /** 565 * mei_cldev_disable - disable me client device 566 * disconnect form the me client 567 * 568 * @cldev: me client device 569 * 570 * Return: 0 on success and < 0 on error 571 */ 572 int mei_cldev_disable(struct mei_cl_device *cldev) 573 { 574 struct mei_device *bus; 575 struct mei_cl *cl; 576 int err; 577 578 if (!cldev) 579 return -ENODEV; 580 581 cl = cldev->cl; 582 583 bus = cldev->bus; 584 585 mei_cldev_unregister_callbacks(cldev); 586 587 mutex_lock(&bus->device_lock); 588 589 if (!mei_cl_is_connected(cl)) { 590 dev_dbg(bus->dev, "Already disconnected\n"); 591 err = 0; 592 goto out; 593 } 594 595 err = mei_cl_disconnect(cl); 596 if (err < 0) 597 dev_err(bus->dev, "Could not disconnect from the ME client\n"); 598 599 out: 600 /* Flush queues and remove any pending read */ 601 mei_cl_flush_queues(cl, NULL); 602 mei_cl_unlink(cl); 603 604 mutex_unlock(&bus->device_lock); 605 return err; 606 } 607 EXPORT_SYMBOL_GPL(mei_cldev_disable); 608 609 /** 610 * mei_cl_device_find - find matching entry in the driver id table 611 * 612 * @cldev: me client device 613 * @cldrv: me client driver 614 * 615 * Return: id on success; NULL if no id is matching 616 */ 617 static const 618 struct mei_cl_device_id *mei_cl_device_find(struct mei_cl_device *cldev, 619 struct mei_cl_driver *cldrv) 620 { 621 const struct mei_cl_device_id *id; 622 const uuid_le *uuid; 623 u8 version; 624 bool match; 625 626 uuid = mei_me_cl_uuid(cldev->me_cl); 627 version = mei_me_cl_ver(cldev->me_cl); 628 629 id = cldrv->id_table; 630 while (uuid_le_cmp(NULL_UUID_LE, id->uuid)) { 631 if (!uuid_le_cmp(*uuid, id->uuid)) { 632 match = true; 633 634 if (cldev->name[0]) 635 if (strncmp(cldev->name, id->name, 636 sizeof(id->name))) 637 match = false; 638 639 if (id->version != MEI_CL_VERSION_ANY) 640 if (id->version != version) 641 match = false; 642 if (match) 643 return id; 644 } 645 646 id++; 647 } 648 649 return NULL; 650 } 651 652 /** 653 * mei_cl_device_match - device match function 654 * 655 * @dev: device 656 * @drv: driver 657 * 658 * Return: 1 if matching device was found 0 otherwise 659 */ 660 static int mei_cl_device_match(struct device *dev, struct device_driver *drv) 661 { 662 struct mei_cl_device *cldev = to_mei_cl_device(dev); 663 struct mei_cl_driver *cldrv = to_mei_cl_driver(drv); 664 const struct mei_cl_device_id *found_id; 665 666 if (!cldev) 667 return 0; 668 669 if (!cldev->do_match) 670 return 0; 671 672 if (!cldrv || !cldrv->id_table) 673 return 0; 674 675 found_id = mei_cl_device_find(cldev, cldrv); 676 if (found_id) 677 return 1; 678 679 return 0; 680 } 681 682 /** 683 * mei_cl_device_probe - bus probe function 684 * 685 * @dev: device 686 * 687 * Return: 0 on success; < 0 otherwise 688 */ 689 static int mei_cl_device_probe(struct device *dev) 690 { 691 struct mei_cl_device *cldev; 692 struct mei_cl_driver *cldrv; 693 const struct mei_cl_device_id *id; 694 int ret; 695 696 cldev = to_mei_cl_device(dev); 697 cldrv = to_mei_cl_driver(dev->driver); 698 699 if (!cldev) 700 return 0; 701 702 if (!cldrv || !cldrv->probe) 703 return -ENODEV; 704 705 id = mei_cl_device_find(cldev, cldrv); 706 if (!id) 707 return -ENODEV; 708 709 if (!mei_cl_bus_module_get(cldev)) { 710 dev_err(&cldev->dev, "get hw module failed"); 711 return -ENODEV; 712 } 713 714 ret = cldrv->probe(cldev, id); 715 if (ret) { 716 mei_cl_bus_module_put(cldev); 717 return ret; 718 } 719 720 __module_get(THIS_MODULE); 721 return 0; 722 } 723 724 /** 725 * mei_cl_device_remove - remove device from the bus 726 * 727 * @dev: device 728 * 729 * Return: 0 on success; < 0 otherwise 730 */ 731 static int mei_cl_device_remove(struct device *dev) 732 { 733 struct mei_cl_device *cldev = to_mei_cl_device(dev); 734 struct mei_cl_driver *cldrv; 735 int ret = 0; 736 737 if (!cldev || !dev->driver) 738 return 0; 739 740 cldrv = to_mei_cl_driver(dev->driver); 741 if (cldrv->remove) 742 ret = cldrv->remove(cldev); 743 744 mei_cldev_unregister_callbacks(cldev); 745 746 mei_cl_bus_module_put(cldev); 747 module_put(THIS_MODULE); 748 dev->driver = NULL; 749 return ret; 750 751 } 752 753 static ssize_t name_show(struct device *dev, struct device_attribute *a, 754 char *buf) 755 { 756 struct mei_cl_device *cldev = to_mei_cl_device(dev); 757 758 return scnprintf(buf, PAGE_SIZE, "%s", cldev->name); 759 } 760 static DEVICE_ATTR_RO(name); 761 762 static ssize_t uuid_show(struct device *dev, struct device_attribute *a, 763 char *buf) 764 { 765 struct mei_cl_device *cldev = to_mei_cl_device(dev); 766 const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl); 767 768 return scnprintf(buf, PAGE_SIZE, "%pUl", uuid); 769 } 770 static DEVICE_ATTR_RO(uuid); 771 772 static ssize_t version_show(struct device *dev, struct device_attribute *a, 773 char *buf) 774 { 775 struct mei_cl_device *cldev = to_mei_cl_device(dev); 776 u8 version = mei_me_cl_ver(cldev->me_cl); 777 778 return scnprintf(buf, PAGE_SIZE, "%02X", version); 779 } 780 static DEVICE_ATTR_RO(version); 781 782 static ssize_t modalias_show(struct device *dev, struct device_attribute *a, 783 char *buf) 784 { 785 struct mei_cl_device *cldev = to_mei_cl_device(dev); 786 const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl); 787 u8 version = mei_me_cl_ver(cldev->me_cl); 788 789 return scnprintf(buf, PAGE_SIZE, "mei:%s:%pUl:%02X:", 790 cldev->name, uuid, version); 791 } 792 static DEVICE_ATTR_RO(modalias); 793 794 static struct attribute *mei_cldev_attrs[] = { 795 &dev_attr_name.attr, 796 &dev_attr_uuid.attr, 797 &dev_attr_version.attr, 798 &dev_attr_modalias.attr, 799 NULL, 800 }; 801 ATTRIBUTE_GROUPS(mei_cldev); 802 803 /** 804 * mei_cl_device_uevent - me client bus uevent handler 805 * 806 * @dev: device 807 * @env: uevent kobject 808 * 809 * Return: 0 on success -ENOMEM on when add_uevent_var fails 810 */ 811 static int mei_cl_device_uevent(struct device *dev, struct kobj_uevent_env *env) 812 { 813 struct mei_cl_device *cldev = to_mei_cl_device(dev); 814 const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl); 815 u8 version = mei_me_cl_ver(cldev->me_cl); 816 817 if (add_uevent_var(env, "MEI_CL_VERSION=%d", version)) 818 return -ENOMEM; 819 820 if (add_uevent_var(env, "MEI_CL_UUID=%pUl", uuid)) 821 return -ENOMEM; 822 823 if (add_uevent_var(env, "MEI_CL_NAME=%s", cldev->name)) 824 return -ENOMEM; 825 826 if (add_uevent_var(env, "MODALIAS=mei:%s:%pUl:%02X:", 827 cldev->name, uuid, version)) 828 return -ENOMEM; 829 830 return 0; 831 } 832 833 static struct bus_type mei_cl_bus_type = { 834 .name = "mei", 835 .dev_groups = mei_cldev_groups, 836 .match = mei_cl_device_match, 837 .probe = mei_cl_device_probe, 838 .remove = mei_cl_device_remove, 839 .uevent = mei_cl_device_uevent, 840 }; 841 842 static struct mei_device *mei_dev_bus_get(struct mei_device *bus) 843 { 844 if (bus) 845 get_device(bus->dev); 846 847 return bus; 848 } 849 850 static void mei_dev_bus_put(struct mei_device *bus) 851 { 852 if (bus) 853 put_device(bus->dev); 854 } 855 856 static void mei_cl_bus_dev_release(struct device *dev) 857 { 858 struct mei_cl_device *cldev = to_mei_cl_device(dev); 859 860 if (!cldev) 861 return; 862 863 mei_me_cl_put(cldev->me_cl); 864 mei_dev_bus_put(cldev->bus); 865 mei_cl_unlink(cldev->cl); 866 kfree(cldev->cl); 867 kfree(cldev); 868 } 869 870 static const struct device_type mei_cl_device_type = { 871 .release = mei_cl_bus_dev_release, 872 }; 873 874 /** 875 * mei_cl_bus_set_name - set device name for me client device 876 * 877 * @cldev: me client device 878 */ 879 static inline void mei_cl_bus_set_name(struct mei_cl_device *cldev) 880 { 881 dev_set_name(&cldev->dev, "mei:%s:%pUl:%02X", 882 cldev->name, 883 mei_me_cl_uuid(cldev->me_cl), 884 mei_me_cl_ver(cldev->me_cl)); 885 } 886 887 /** 888 * mei_cl_bus_dev_alloc - initialize and allocate mei client device 889 * 890 * @bus: mei device 891 * @me_cl: me client 892 * 893 * Return: allocated device structur or NULL on allocation failure 894 */ 895 static struct mei_cl_device *mei_cl_bus_dev_alloc(struct mei_device *bus, 896 struct mei_me_client *me_cl) 897 { 898 struct mei_cl_device *cldev; 899 struct mei_cl *cl; 900 901 cldev = kzalloc(sizeof(struct mei_cl_device), GFP_KERNEL); 902 if (!cldev) 903 return NULL; 904 905 cl = mei_cl_allocate(bus); 906 if (!cl) { 907 kfree(cldev); 908 return NULL; 909 } 910 911 device_initialize(&cldev->dev); 912 cldev->dev.parent = bus->dev; 913 cldev->dev.bus = &mei_cl_bus_type; 914 cldev->dev.type = &mei_cl_device_type; 915 cldev->bus = mei_dev_bus_get(bus); 916 cldev->me_cl = mei_me_cl_get(me_cl); 917 cldev->cl = cl; 918 mei_cl_bus_set_name(cldev); 919 cldev->is_added = 0; 920 INIT_LIST_HEAD(&cldev->bus_list); 921 922 return cldev; 923 } 924 925 /** 926 * mei_cl_dev_setup - setup me client device 927 * run fix up routines and set the device name 928 * 929 * @bus: mei device 930 * @cldev: me client device 931 * 932 * Return: true if the device is eligible for enumeration 933 */ 934 static bool mei_cl_bus_dev_setup(struct mei_device *bus, 935 struct mei_cl_device *cldev) 936 { 937 cldev->do_match = 1; 938 mei_cl_bus_dev_fixup(cldev); 939 940 /* the device name can change during fix up */ 941 if (cldev->do_match) 942 mei_cl_bus_set_name(cldev); 943 944 return cldev->do_match == 1; 945 } 946 947 /** 948 * mei_cl_bus_dev_add - add me client devices 949 * 950 * @cldev: me client device 951 * 952 * Return: 0 on success; < 0 on failre 953 */ 954 static int mei_cl_bus_dev_add(struct mei_cl_device *cldev) 955 { 956 int ret; 957 958 dev_dbg(cldev->bus->dev, "adding %pUL:%02X\n", 959 mei_me_cl_uuid(cldev->me_cl), 960 mei_me_cl_ver(cldev->me_cl)); 961 ret = device_add(&cldev->dev); 962 if (!ret) 963 cldev->is_added = 1; 964 965 return ret; 966 } 967 968 /** 969 * mei_cl_bus_dev_stop - stop the driver 970 * 971 * @cldev: me client device 972 */ 973 static void mei_cl_bus_dev_stop(struct mei_cl_device *cldev) 974 { 975 if (cldev->is_added) 976 device_release_driver(&cldev->dev); 977 } 978 979 /** 980 * mei_cl_bus_dev_destroy - destroy me client devices object 981 * 982 * @cldev: me client device 983 * 984 * Locking: called under "dev->cl_bus_lock" lock 985 */ 986 static void mei_cl_bus_dev_destroy(struct mei_cl_device *cldev) 987 { 988 989 WARN_ON(!mutex_is_locked(&cldev->bus->cl_bus_lock)); 990 991 if (!cldev->is_added) 992 return; 993 994 device_del(&cldev->dev); 995 996 list_del_init(&cldev->bus_list); 997 998 cldev->is_added = 0; 999 put_device(&cldev->dev); 1000 } 1001 1002 /** 1003 * mei_cl_bus_remove_device - remove a devices form the bus 1004 * 1005 * @cldev: me client device 1006 */ 1007 static void mei_cl_bus_remove_device(struct mei_cl_device *cldev) 1008 { 1009 mei_cl_bus_dev_stop(cldev); 1010 mei_cl_bus_dev_destroy(cldev); 1011 } 1012 1013 /** 1014 * mei_cl_bus_remove_devices - remove all devices form the bus 1015 * 1016 * @bus: mei device 1017 */ 1018 void mei_cl_bus_remove_devices(struct mei_device *bus) 1019 { 1020 struct mei_cl_device *cldev, *next; 1021 1022 mutex_lock(&bus->cl_bus_lock); 1023 list_for_each_entry_safe(cldev, next, &bus->device_list, bus_list) 1024 mei_cl_bus_remove_device(cldev); 1025 mutex_unlock(&bus->cl_bus_lock); 1026 } 1027 1028 1029 /** 1030 * mei_cl_bus_dev_init - allocate and initializes an mei client devices 1031 * based on me client 1032 * 1033 * @bus: mei device 1034 * @me_cl: me client 1035 * 1036 * Locking: called under "dev->cl_bus_lock" lock 1037 */ 1038 static void mei_cl_bus_dev_init(struct mei_device *bus, 1039 struct mei_me_client *me_cl) 1040 { 1041 struct mei_cl_device *cldev; 1042 1043 WARN_ON(!mutex_is_locked(&bus->cl_bus_lock)); 1044 1045 dev_dbg(bus->dev, "initializing %pUl", mei_me_cl_uuid(me_cl)); 1046 1047 if (me_cl->bus_added) 1048 return; 1049 1050 cldev = mei_cl_bus_dev_alloc(bus, me_cl); 1051 if (!cldev) 1052 return; 1053 1054 me_cl->bus_added = true; 1055 list_add_tail(&cldev->bus_list, &bus->device_list); 1056 1057 } 1058 1059 /** 1060 * mei_cl_bus_rescan - scan me clients list and add create 1061 * devices for eligible clients 1062 * 1063 * @bus: mei device 1064 */ 1065 static void mei_cl_bus_rescan(struct mei_device *bus) 1066 { 1067 struct mei_cl_device *cldev, *n; 1068 struct mei_me_client *me_cl; 1069 1070 mutex_lock(&bus->cl_bus_lock); 1071 1072 down_read(&bus->me_clients_rwsem); 1073 list_for_each_entry(me_cl, &bus->me_clients, list) 1074 mei_cl_bus_dev_init(bus, me_cl); 1075 up_read(&bus->me_clients_rwsem); 1076 1077 list_for_each_entry_safe(cldev, n, &bus->device_list, bus_list) { 1078 1079 if (!mei_me_cl_is_active(cldev->me_cl)) { 1080 mei_cl_bus_remove_device(cldev); 1081 continue; 1082 } 1083 1084 if (cldev->is_added) 1085 continue; 1086 1087 if (mei_cl_bus_dev_setup(bus, cldev)) 1088 mei_cl_bus_dev_add(cldev); 1089 else { 1090 list_del_init(&cldev->bus_list); 1091 put_device(&cldev->dev); 1092 } 1093 } 1094 mutex_unlock(&bus->cl_bus_lock); 1095 1096 dev_dbg(bus->dev, "rescan end"); 1097 } 1098 1099 void mei_cl_bus_rescan_work(struct work_struct *work) 1100 { 1101 struct mei_device *bus = 1102 container_of(work, struct mei_device, bus_rescan_work); 1103 1104 mei_cl_bus_rescan(bus); 1105 } 1106 1107 int __mei_cldev_driver_register(struct mei_cl_driver *cldrv, 1108 struct module *owner) 1109 { 1110 int err; 1111 1112 cldrv->driver.name = cldrv->name; 1113 cldrv->driver.owner = owner; 1114 cldrv->driver.bus = &mei_cl_bus_type; 1115 1116 err = driver_register(&cldrv->driver); 1117 if (err) 1118 return err; 1119 1120 pr_debug("mei: driver [%s] registered\n", cldrv->driver.name); 1121 1122 return 0; 1123 } 1124 EXPORT_SYMBOL_GPL(__mei_cldev_driver_register); 1125 1126 void mei_cldev_driver_unregister(struct mei_cl_driver *cldrv) 1127 { 1128 driver_unregister(&cldrv->driver); 1129 1130 pr_debug("mei: driver [%s] unregistered\n", cldrv->driver.name); 1131 } 1132 EXPORT_SYMBOL_GPL(mei_cldev_driver_unregister); 1133 1134 1135 int __init mei_cl_bus_init(void) 1136 { 1137 return bus_register(&mei_cl_bus_type); 1138 } 1139 1140 void __exit mei_cl_bus_exit(void) 1141 { 1142 bus_unregister(&mei_cl_bus_type); 1143 } 1144