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 mei_cl_read_cb(cl, NULL) || 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 mei_cl_read_cb(cl, NULL) || 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_cl_del_rd_completed(cl, 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 if (mei_cl_is_connected(cldev->cl)) 280 mei_cl_read_start(cldev->cl, mei_cl_mtu(cldev->cl), NULL); 281 mutex_unlock(&bus->device_lock); 282 } 283 284 /** 285 * mei_cl_bus_notif_work - dispatch FW notif event for a bus device 286 * 287 * @work: work 288 */ 289 static void mei_cl_bus_notif_work(struct work_struct *work) 290 { 291 struct mei_cl_device *cldev; 292 293 cldev = container_of(work, struct mei_cl_device, notif_work); 294 295 if (cldev->notif_cb) 296 cldev->notif_cb(cldev); 297 } 298 299 /** 300 * mei_cl_bus_notify_event - schedule notify cb on bus client 301 * 302 * @cl: host client 303 * 304 * Return: true if event was scheduled 305 * false if the client is not waiting for event 306 */ 307 bool mei_cl_bus_notify_event(struct mei_cl *cl) 308 { 309 struct mei_cl_device *cldev = cl->cldev; 310 311 if (!cldev || !cldev->notif_cb) 312 return false; 313 314 if (!cl->notify_ev) 315 return false; 316 317 schedule_work(&cldev->notif_work); 318 319 cl->notify_ev = false; 320 321 return true; 322 } 323 324 /** 325 * mei_cl_bus_rx_event - schedule rx event 326 * 327 * @cl: host client 328 * 329 * Return: true if event was scheduled 330 * false if the client is not waiting for event 331 */ 332 bool mei_cl_bus_rx_event(struct mei_cl *cl) 333 { 334 struct mei_cl_device *cldev = cl->cldev; 335 336 if (!cldev || !cldev->rx_cb) 337 return false; 338 339 schedule_work(&cldev->rx_work); 340 341 return true; 342 } 343 344 /** 345 * mei_cldev_register_rx_cb - register Rx event callback 346 * 347 * @cldev: me client devices 348 * @rx_cb: callback function 349 * 350 * Return: 0 on success 351 * -EALREADY if an callback is already registered 352 * <0 on other errors 353 */ 354 int mei_cldev_register_rx_cb(struct mei_cl_device *cldev, mei_cldev_cb_t rx_cb) 355 { 356 struct mei_device *bus = cldev->bus; 357 int ret; 358 359 if (!rx_cb) 360 return -EINVAL; 361 if (cldev->rx_cb) 362 return -EALREADY; 363 364 cldev->rx_cb = rx_cb; 365 INIT_WORK(&cldev->rx_work, mei_cl_bus_rx_work); 366 367 mutex_lock(&bus->device_lock); 368 if (mei_cl_is_connected(cldev->cl)) 369 ret = mei_cl_read_start(cldev->cl, mei_cl_mtu(cldev->cl), NULL); 370 else 371 ret = -ENODEV; 372 mutex_unlock(&bus->device_lock); 373 if (ret && ret != -EBUSY) { 374 cancel_work_sync(&cldev->rx_work); 375 cldev->rx_cb = NULL; 376 return ret; 377 } 378 379 return 0; 380 } 381 EXPORT_SYMBOL_GPL(mei_cldev_register_rx_cb); 382 383 /** 384 * mei_cldev_register_notif_cb - register FW notification event callback 385 * 386 * @cldev: me client devices 387 * @notif_cb: callback function 388 * 389 * Return: 0 on success 390 * -EALREADY if an callback is already registered 391 * <0 on other errors 392 */ 393 int mei_cldev_register_notif_cb(struct mei_cl_device *cldev, 394 mei_cldev_cb_t notif_cb) 395 { 396 struct mei_device *bus = cldev->bus; 397 int ret; 398 399 if (!notif_cb) 400 return -EINVAL; 401 402 if (cldev->notif_cb) 403 return -EALREADY; 404 405 cldev->notif_cb = notif_cb; 406 INIT_WORK(&cldev->notif_work, mei_cl_bus_notif_work); 407 408 mutex_lock(&bus->device_lock); 409 ret = mei_cl_notify_request(cldev->cl, NULL, 1); 410 mutex_unlock(&bus->device_lock); 411 if (ret) { 412 cancel_work_sync(&cldev->notif_work); 413 cldev->notif_cb = NULL; 414 return ret; 415 } 416 417 return 0; 418 } 419 EXPORT_SYMBOL_GPL(mei_cldev_register_notif_cb); 420 421 /** 422 * mei_cldev_get_drvdata - driver data getter 423 * 424 * @cldev: mei client device 425 * 426 * Return: driver private data 427 */ 428 void *mei_cldev_get_drvdata(const struct mei_cl_device *cldev) 429 { 430 return dev_get_drvdata(&cldev->dev); 431 } 432 EXPORT_SYMBOL_GPL(mei_cldev_get_drvdata); 433 434 /** 435 * mei_cldev_set_drvdata - driver data setter 436 * 437 * @cldev: mei client device 438 * @data: data to store 439 */ 440 void mei_cldev_set_drvdata(struct mei_cl_device *cldev, void *data) 441 { 442 dev_set_drvdata(&cldev->dev, data); 443 } 444 EXPORT_SYMBOL_GPL(mei_cldev_set_drvdata); 445 446 /** 447 * mei_cldev_uuid - return uuid of the underlying me client 448 * 449 * @cldev: mei client device 450 * 451 * Return: me client uuid 452 */ 453 const uuid_le *mei_cldev_uuid(const struct mei_cl_device *cldev) 454 { 455 return mei_me_cl_uuid(cldev->me_cl); 456 } 457 EXPORT_SYMBOL_GPL(mei_cldev_uuid); 458 459 /** 460 * mei_cldev_ver - return protocol version of the underlying me client 461 * 462 * @cldev: mei client device 463 * 464 * Return: me client protocol version 465 */ 466 u8 mei_cldev_ver(const struct mei_cl_device *cldev) 467 { 468 return mei_me_cl_ver(cldev->me_cl); 469 } 470 EXPORT_SYMBOL_GPL(mei_cldev_ver); 471 472 /** 473 * mei_cldev_enabled - check whether the device is enabled 474 * 475 * @cldev: mei client device 476 * 477 * Return: true if me client is initialized and connected 478 */ 479 bool mei_cldev_enabled(struct mei_cl_device *cldev) 480 { 481 return mei_cl_is_connected(cldev->cl); 482 } 483 EXPORT_SYMBOL_GPL(mei_cldev_enabled); 484 485 /** 486 * mei_cl_bus_module_get - acquire module of the underlying 487 * hw driver. 488 * 489 * @cldev: mei client device 490 * 491 * Return: true on success; false if the module was removed. 492 */ 493 static bool mei_cl_bus_module_get(struct mei_cl_device *cldev) 494 { 495 return try_module_get(cldev->bus->dev->driver->owner); 496 } 497 498 /** 499 * mei_cl_bus_module_put - release the underlying hw module. 500 * 501 * @cldev: mei client device 502 */ 503 static void mei_cl_bus_module_put(struct mei_cl_device *cldev) 504 { 505 module_put(cldev->bus->dev->driver->owner); 506 } 507 508 /** 509 * mei_cl_bus_vtag - get bus vtag entry wrapper 510 * The tag for bus client is always first. 511 * 512 * @cl: host client 513 * 514 * Return: bus vtag or NULL 515 */ 516 static inline struct mei_cl_vtag *mei_cl_bus_vtag(struct mei_cl *cl) 517 { 518 return list_first_entry_or_null(&cl->vtag_map, 519 struct mei_cl_vtag, list); 520 } 521 522 /** 523 * mei_cl_bus_vtag_alloc - add bus client entry to vtag map 524 * 525 * @cldev: me client device 526 * 527 * Return: 528 * * 0 on success 529 * * -ENOMEM if memory allocation failed 530 */ 531 static int mei_cl_bus_vtag_alloc(struct mei_cl_device *cldev) 532 { 533 struct mei_cl *cl = cldev->cl; 534 struct mei_cl_vtag *cl_vtag; 535 536 /* 537 * Bail out if the client does not supports vtags 538 * or has already allocated one 539 */ 540 if (mei_cl_vt_support_check(cl) || mei_cl_bus_vtag(cl)) 541 return 0; 542 543 cl_vtag = mei_cl_vtag_alloc(NULL, 0); 544 if (IS_ERR(cl_vtag)) 545 return -ENOMEM; 546 547 list_add_tail(&cl_vtag->list, &cl->vtag_map); 548 549 return 0; 550 } 551 552 /** 553 * mei_cl_bus_vtag_free - remove the bus entry from vtag map 554 * 555 * @cldev: me client device 556 */ 557 static void mei_cl_bus_vtag_free(struct mei_cl_device *cldev) 558 { 559 struct mei_cl *cl = cldev->cl; 560 struct mei_cl_vtag *cl_vtag; 561 562 cl_vtag = mei_cl_bus_vtag(cl); 563 if (!cl_vtag) 564 return; 565 566 list_del(&cl_vtag->list); 567 kfree(cl_vtag); 568 } 569 570 /** 571 * mei_cldev_enable - enable me client device 572 * create connection with me client 573 * 574 * @cldev: me client device 575 * 576 * Return: 0 on success and < 0 on error 577 */ 578 int mei_cldev_enable(struct mei_cl_device *cldev) 579 { 580 struct mei_device *bus = cldev->bus; 581 struct mei_cl *cl; 582 int ret; 583 584 cl = cldev->cl; 585 586 mutex_lock(&bus->device_lock); 587 if (cl->state == MEI_FILE_UNINITIALIZED) { 588 ret = mei_cl_link(cl); 589 if (ret) 590 goto out; 591 /* update pointers */ 592 cl->cldev = cldev; 593 } 594 595 if (mei_cl_is_connected(cl)) { 596 ret = 0; 597 goto out; 598 } 599 600 if (!mei_me_cl_is_active(cldev->me_cl)) { 601 dev_err(&cldev->dev, "me client is not active\n"); 602 ret = -ENOTTY; 603 goto out; 604 } 605 606 ret = mei_cl_bus_vtag_alloc(cldev); 607 if (ret) 608 goto out; 609 610 ret = mei_cl_connect(cl, cldev->me_cl, NULL); 611 if (ret < 0) { 612 dev_err(&cldev->dev, "cannot connect\n"); 613 mei_cl_bus_vtag_free(cldev); 614 } 615 616 out: 617 mutex_unlock(&bus->device_lock); 618 619 return ret; 620 } 621 EXPORT_SYMBOL_GPL(mei_cldev_enable); 622 623 /** 624 * mei_cldev_unregister_callbacks - internal wrapper for unregistering 625 * callbacks. 626 * 627 * @cldev: client device 628 */ 629 static void mei_cldev_unregister_callbacks(struct mei_cl_device *cldev) 630 { 631 if (cldev->rx_cb) { 632 cancel_work_sync(&cldev->rx_work); 633 cldev->rx_cb = NULL; 634 } 635 636 if (cldev->notif_cb) { 637 cancel_work_sync(&cldev->notif_work); 638 cldev->notif_cb = NULL; 639 } 640 } 641 642 /** 643 * mei_cldev_disable - disable me client device 644 * disconnect form the me client 645 * 646 * @cldev: me client device 647 * 648 * Return: 0 on success and < 0 on error 649 */ 650 int mei_cldev_disable(struct mei_cl_device *cldev) 651 { 652 struct mei_device *bus; 653 struct mei_cl *cl; 654 int err; 655 656 if (!cldev) 657 return -ENODEV; 658 659 cl = cldev->cl; 660 661 bus = cldev->bus; 662 663 mei_cldev_unregister_callbacks(cldev); 664 665 mutex_lock(&bus->device_lock); 666 667 mei_cl_bus_vtag_free(cldev); 668 669 if (!mei_cl_is_connected(cl)) { 670 dev_dbg(bus->dev, "Already disconnected\n"); 671 err = 0; 672 goto out; 673 } 674 675 err = mei_cl_disconnect(cl); 676 if (err < 0) 677 dev_err(bus->dev, "Could not disconnect from the ME client\n"); 678 679 out: 680 /* Flush queues and remove any pending read */ 681 mei_cl_flush_queues(cl, NULL); 682 mei_cl_unlink(cl); 683 684 mutex_unlock(&bus->device_lock); 685 return err; 686 } 687 EXPORT_SYMBOL_GPL(mei_cldev_disable); 688 689 /** 690 * mei_cl_device_find - find matching entry in the driver id table 691 * 692 * @cldev: me client device 693 * @cldrv: me client driver 694 * 695 * Return: id on success; NULL if no id is matching 696 */ 697 static const 698 struct mei_cl_device_id *mei_cl_device_find(struct mei_cl_device *cldev, 699 struct mei_cl_driver *cldrv) 700 { 701 const struct mei_cl_device_id *id; 702 const uuid_le *uuid; 703 u8 version; 704 bool match; 705 706 uuid = mei_me_cl_uuid(cldev->me_cl); 707 version = mei_me_cl_ver(cldev->me_cl); 708 709 id = cldrv->id_table; 710 while (uuid_le_cmp(NULL_UUID_LE, id->uuid)) { 711 if (!uuid_le_cmp(*uuid, id->uuid)) { 712 match = true; 713 714 if (cldev->name[0]) 715 if (strncmp(cldev->name, id->name, 716 sizeof(id->name))) 717 match = false; 718 719 if (id->version != MEI_CL_VERSION_ANY) 720 if (id->version != version) 721 match = false; 722 if (match) 723 return id; 724 } 725 726 id++; 727 } 728 729 return NULL; 730 } 731 732 /** 733 * mei_cl_device_match - device match function 734 * 735 * @dev: device 736 * @drv: driver 737 * 738 * Return: 1 if matching device was found 0 otherwise 739 */ 740 static int mei_cl_device_match(struct device *dev, struct device_driver *drv) 741 { 742 struct mei_cl_device *cldev = to_mei_cl_device(dev); 743 struct mei_cl_driver *cldrv = to_mei_cl_driver(drv); 744 const struct mei_cl_device_id *found_id; 745 746 if (!cldev) 747 return 0; 748 749 if (!cldev->do_match) 750 return 0; 751 752 if (!cldrv || !cldrv->id_table) 753 return 0; 754 755 found_id = mei_cl_device_find(cldev, cldrv); 756 if (found_id) 757 return 1; 758 759 return 0; 760 } 761 762 /** 763 * mei_cl_device_probe - bus probe function 764 * 765 * @dev: device 766 * 767 * Return: 0 on success; < 0 otherwise 768 */ 769 static int mei_cl_device_probe(struct device *dev) 770 { 771 struct mei_cl_device *cldev; 772 struct mei_cl_driver *cldrv; 773 const struct mei_cl_device_id *id; 774 int ret; 775 776 cldev = to_mei_cl_device(dev); 777 cldrv = to_mei_cl_driver(dev->driver); 778 779 if (!cldev) 780 return 0; 781 782 if (!cldrv || !cldrv->probe) 783 return -ENODEV; 784 785 id = mei_cl_device_find(cldev, cldrv); 786 if (!id) 787 return -ENODEV; 788 789 if (!mei_cl_bus_module_get(cldev)) { 790 dev_err(&cldev->dev, "get hw module failed"); 791 return -ENODEV; 792 } 793 794 ret = cldrv->probe(cldev, id); 795 if (ret) { 796 mei_cl_bus_module_put(cldev); 797 return ret; 798 } 799 800 __module_get(THIS_MODULE); 801 return 0; 802 } 803 804 /** 805 * mei_cl_device_remove - remove device from the bus 806 * 807 * @dev: device 808 * 809 * Return: 0 on success; < 0 otherwise 810 */ 811 static int mei_cl_device_remove(struct device *dev) 812 { 813 struct mei_cl_device *cldev = to_mei_cl_device(dev); 814 struct mei_cl_driver *cldrv; 815 int ret = 0; 816 817 if (!cldev || !dev->driver) 818 return 0; 819 820 cldrv = to_mei_cl_driver(dev->driver); 821 if (cldrv->remove) 822 ret = cldrv->remove(cldev); 823 824 mei_cldev_unregister_callbacks(cldev); 825 826 mei_cl_bus_module_put(cldev); 827 module_put(THIS_MODULE); 828 829 return ret; 830 } 831 832 static ssize_t name_show(struct device *dev, struct device_attribute *a, 833 char *buf) 834 { 835 struct mei_cl_device *cldev = to_mei_cl_device(dev); 836 837 return scnprintf(buf, PAGE_SIZE, "%s", cldev->name); 838 } 839 static DEVICE_ATTR_RO(name); 840 841 static ssize_t uuid_show(struct device *dev, struct device_attribute *a, 842 char *buf) 843 { 844 struct mei_cl_device *cldev = to_mei_cl_device(dev); 845 const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl); 846 847 return sprintf(buf, "%pUl", uuid); 848 } 849 static DEVICE_ATTR_RO(uuid); 850 851 static ssize_t version_show(struct device *dev, struct device_attribute *a, 852 char *buf) 853 { 854 struct mei_cl_device *cldev = to_mei_cl_device(dev); 855 u8 version = mei_me_cl_ver(cldev->me_cl); 856 857 return sprintf(buf, "%02X", version); 858 } 859 static DEVICE_ATTR_RO(version); 860 861 static ssize_t modalias_show(struct device *dev, struct device_attribute *a, 862 char *buf) 863 { 864 struct mei_cl_device *cldev = to_mei_cl_device(dev); 865 const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl); 866 u8 version = mei_me_cl_ver(cldev->me_cl); 867 868 return scnprintf(buf, PAGE_SIZE, "mei:%s:%pUl:%02X:", 869 cldev->name, uuid, version); 870 } 871 static DEVICE_ATTR_RO(modalias); 872 873 static ssize_t max_conn_show(struct device *dev, struct device_attribute *a, 874 char *buf) 875 { 876 struct mei_cl_device *cldev = to_mei_cl_device(dev); 877 u8 maxconn = mei_me_cl_max_conn(cldev->me_cl); 878 879 return sprintf(buf, "%d", maxconn); 880 } 881 static DEVICE_ATTR_RO(max_conn); 882 883 static ssize_t fixed_show(struct device *dev, struct device_attribute *a, 884 char *buf) 885 { 886 struct mei_cl_device *cldev = to_mei_cl_device(dev); 887 u8 fixed = mei_me_cl_fixed(cldev->me_cl); 888 889 return sprintf(buf, "%d", fixed); 890 } 891 static DEVICE_ATTR_RO(fixed); 892 893 static ssize_t vtag_show(struct device *dev, struct device_attribute *a, 894 char *buf) 895 { 896 struct mei_cl_device *cldev = to_mei_cl_device(dev); 897 bool vt = mei_me_cl_vt(cldev->me_cl); 898 899 return sprintf(buf, "%d", vt); 900 } 901 static DEVICE_ATTR_RO(vtag); 902 903 static ssize_t max_len_show(struct device *dev, struct device_attribute *a, 904 char *buf) 905 { 906 struct mei_cl_device *cldev = to_mei_cl_device(dev); 907 u32 maxlen = mei_me_cl_max_len(cldev->me_cl); 908 909 return sprintf(buf, "%u", maxlen); 910 } 911 static DEVICE_ATTR_RO(max_len); 912 913 static struct attribute *mei_cldev_attrs[] = { 914 &dev_attr_name.attr, 915 &dev_attr_uuid.attr, 916 &dev_attr_version.attr, 917 &dev_attr_modalias.attr, 918 &dev_attr_max_conn.attr, 919 &dev_attr_fixed.attr, 920 &dev_attr_vtag.attr, 921 &dev_attr_max_len.attr, 922 NULL, 923 }; 924 ATTRIBUTE_GROUPS(mei_cldev); 925 926 /** 927 * mei_cl_device_uevent - me client bus uevent handler 928 * 929 * @dev: device 930 * @env: uevent kobject 931 * 932 * Return: 0 on success -ENOMEM on when add_uevent_var fails 933 */ 934 static int mei_cl_device_uevent(struct device *dev, struct kobj_uevent_env *env) 935 { 936 struct mei_cl_device *cldev = to_mei_cl_device(dev); 937 const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl); 938 u8 version = mei_me_cl_ver(cldev->me_cl); 939 940 if (add_uevent_var(env, "MEI_CL_VERSION=%d", version)) 941 return -ENOMEM; 942 943 if (add_uevent_var(env, "MEI_CL_UUID=%pUl", uuid)) 944 return -ENOMEM; 945 946 if (add_uevent_var(env, "MEI_CL_NAME=%s", cldev->name)) 947 return -ENOMEM; 948 949 if (add_uevent_var(env, "MODALIAS=mei:%s:%pUl:%02X:", 950 cldev->name, uuid, version)) 951 return -ENOMEM; 952 953 return 0; 954 } 955 956 static struct bus_type mei_cl_bus_type = { 957 .name = "mei", 958 .dev_groups = mei_cldev_groups, 959 .match = mei_cl_device_match, 960 .probe = mei_cl_device_probe, 961 .remove = mei_cl_device_remove, 962 .uevent = mei_cl_device_uevent, 963 }; 964 965 static struct mei_device *mei_dev_bus_get(struct mei_device *bus) 966 { 967 if (bus) 968 get_device(bus->dev); 969 970 return bus; 971 } 972 973 static void mei_dev_bus_put(struct mei_device *bus) 974 { 975 if (bus) 976 put_device(bus->dev); 977 } 978 979 static void mei_cl_bus_dev_release(struct device *dev) 980 { 981 struct mei_cl_device *cldev = to_mei_cl_device(dev); 982 983 if (!cldev) 984 return; 985 986 mei_me_cl_put(cldev->me_cl); 987 mei_dev_bus_put(cldev->bus); 988 mei_cl_unlink(cldev->cl); 989 kfree(cldev->cl); 990 kfree(cldev); 991 } 992 993 static const struct device_type mei_cl_device_type = { 994 .release = mei_cl_bus_dev_release, 995 }; 996 997 /** 998 * mei_cl_bus_set_name - set device name for me client device 999 * <controller>-<client device> 1000 * Example: 0000:00:16.0-55213584-9a29-4916-badf-0fb7ed682aeb 1001 * 1002 * @cldev: me client device 1003 */ 1004 static inline void mei_cl_bus_set_name(struct mei_cl_device *cldev) 1005 { 1006 dev_set_name(&cldev->dev, "%s-%pUl", 1007 dev_name(cldev->bus->dev), 1008 mei_me_cl_uuid(cldev->me_cl)); 1009 } 1010 1011 /** 1012 * mei_cl_bus_dev_alloc - initialize and allocate mei client device 1013 * 1014 * @bus: mei device 1015 * @me_cl: me client 1016 * 1017 * Return: allocated device structur or NULL on allocation failure 1018 */ 1019 static struct mei_cl_device *mei_cl_bus_dev_alloc(struct mei_device *bus, 1020 struct mei_me_client *me_cl) 1021 { 1022 struct mei_cl_device *cldev; 1023 struct mei_cl *cl; 1024 1025 cldev = kzalloc(sizeof(*cldev), GFP_KERNEL); 1026 if (!cldev) 1027 return NULL; 1028 1029 cl = mei_cl_allocate(bus); 1030 if (!cl) { 1031 kfree(cldev); 1032 return NULL; 1033 } 1034 1035 device_initialize(&cldev->dev); 1036 cldev->dev.parent = bus->dev; 1037 cldev->dev.bus = &mei_cl_bus_type; 1038 cldev->dev.type = &mei_cl_device_type; 1039 cldev->bus = mei_dev_bus_get(bus); 1040 cldev->me_cl = mei_me_cl_get(me_cl); 1041 cldev->cl = cl; 1042 mei_cl_bus_set_name(cldev); 1043 cldev->is_added = 0; 1044 INIT_LIST_HEAD(&cldev->bus_list); 1045 1046 return cldev; 1047 } 1048 1049 /** 1050 * mei_cl_dev_setup - setup me client device 1051 * run fix up routines and set the device name 1052 * 1053 * @bus: mei device 1054 * @cldev: me client device 1055 * 1056 * Return: true if the device is eligible for enumeration 1057 */ 1058 static bool mei_cl_bus_dev_setup(struct mei_device *bus, 1059 struct mei_cl_device *cldev) 1060 { 1061 cldev->do_match = 1; 1062 mei_cl_bus_dev_fixup(cldev); 1063 1064 /* the device name can change during fix up */ 1065 if (cldev->do_match) 1066 mei_cl_bus_set_name(cldev); 1067 1068 return cldev->do_match == 1; 1069 } 1070 1071 /** 1072 * mei_cl_bus_dev_add - add me client devices 1073 * 1074 * @cldev: me client device 1075 * 1076 * Return: 0 on success; < 0 on failre 1077 */ 1078 static int mei_cl_bus_dev_add(struct mei_cl_device *cldev) 1079 { 1080 int ret; 1081 1082 dev_dbg(cldev->bus->dev, "adding %pUL:%02X\n", 1083 mei_me_cl_uuid(cldev->me_cl), 1084 mei_me_cl_ver(cldev->me_cl)); 1085 ret = device_add(&cldev->dev); 1086 if (!ret) 1087 cldev->is_added = 1; 1088 1089 return ret; 1090 } 1091 1092 /** 1093 * mei_cl_bus_dev_stop - stop the driver 1094 * 1095 * @cldev: me client device 1096 */ 1097 static void mei_cl_bus_dev_stop(struct mei_cl_device *cldev) 1098 { 1099 if (cldev->is_added) 1100 device_release_driver(&cldev->dev); 1101 } 1102 1103 /** 1104 * mei_cl_bus_dev_destroy - destroy me client devices object 1105 * 1106 * @cldev: me client device 1107 * 1108 * Locking: called under "dev->cl_bus_lock" lock 1109 */ 1110 static void mei_cl_bus_dev_destroy(struct mei_cl_device *cldev) 1111 { 1112 1113 WARN_ON(!mutex_is_locked(&cldev->bus->cl_bus_lock)); 1114 1115 if (!cldev->is_added) 1116 return; 1117 1118 device_del(&cldev->dev); 1119 1120 list_del_init(&cldev->bus_list); 1121 1122 cldev->is_added = 0; 1123 put_device(&cldev->dev); 1124 } 1125 1126 /** 1127 * mei_cl_bus_remove_device - remove a devices form the bus 1128 * 1129 * @cldev: me client device 1130 */ 1131 static void mei_cl_bus_remove_device(struct mei_cl_device *cldev) 1132 { 1133 mei_cl_bus_dev_stop(cldev); 1134 mei_cl_bus_dev_destroy(cldev); 1135 } 1136 1137 /** 1138 * mei_cl_bus_remove_devices - remove all devices form the bus 1139 * 1140 * @bus: mei device 1141 */ 1142 void mei_cl_bus_remove_devices(struct mei_device *bus) 1143 { 1144 struct mei_cl_device *cldev, *next; 1145 1146 mutex_lock(&bus->cl_bus_lock); 1147 list_for_each_entry_safe(cldev, next, &bus->device_list, bus_list) 1148 mei_cl_bus_remove_device(cldev); 1149 mutex_unlock(&bus->cl_bus_lock); 1150 } 1151 1152 1153 /** 1154 * mei_cl_bus_dev_init - allocate and initializes an mei client devices 1155 * based on me client 1156 * 1157 * @bus: mei device 1158 * @me_cl: me client 1159 * 1160 * Locking: called under "dev->cl_bus_lock" lock 1161 */ 1162 static void mei_cl_bus_dev_init(struct mei_device *bus, 1163 struct mei_me_client *me_cl) 1164 { 1165 struct mei_cl_device *cldev; 1166 1167 WARN_ON(!mutex_is_locked(&bus->cl_bus_lock)); 1168 1169 dev_dbg(bus->dev, "initializing %pUl", mei_me_cl_uuid(me_cl)); 1170 1171 if (me_cl->bus_added) 1172 return; 1173 1174 cldev = mei_cl_bus_dev_alloc(bus, me_cl); 1175 if (!cldev) 1176 return; 1177 1178 me_cl->bus_added = true; 1179 list_add_tail(&cldev->bus_list, &bus->device_list); 1180 1181 } 1182 1183 /** 1184 * mei_cl_bus_rescan - scan me clients list and add create 1185 * devices for eligible clients 1186 * 1187 * @bus: mei device 1188 */ 1189 static void mei_cl_bus_rescan(struct mei_device *bus) 1190 { 1191 struct mei_cl_device *cldev, *n; 1192 struct mei_me_client *me_cl; 1193 1194 mutex_lock(&bus->cl_bus_lock); 1195 1196 down_read(&bus->me_clients_rwsem); 1197 list_for_each_entry(me_cl, &bus->me_clients, list) 1198 mei_cl_bus_dev_init(bus, me_cl); 1199 up_read(&bus->me_clients_rwsem); 1200 1201 list_for_each_entry_safe(cldev, n, &bus->device_list, bus_list) { 1202 1203 if (!mei_me_cl_is_active(cldev->me_cl)) { 1204 mei_cl_bus_remove_device(cldev); 1205 continue; 1206 } 1207 1208 if (cldev->is_added) 1209 continue; 1210 1211 if (mei_cl_bus_dev_setup(bus, cldev)) 1212 mei_cl_bus_dev_add(cldev); 1213 else { 1214 list_del_init(&cldev->bus_list); 1215 put_device(&cldev->dev); 1216 } 1217 } 1218 mutex_unlock(&bus->cl_bus_lock); 1219 1220 dev_dbg(bus->dev, "rescan end"); 1221 } 1222 1223 void mei_cl_bus_rescan_work(struct work_struct *work) 1224 { 1225 struct mei_device *bus = 1226 container_of(work, struct mei_device, bus_rescan_work); 1227 1228 mei_cl_bus_rescan(bus); 1229 } 1230 1231 int __mei_cldev_driver_register(struct mei_cl_driver *cldrv, 1232 struct module *owner) 1233 { 1234 int err; 1235 1236 cldrv->driver.name = cldrv->name; 1237 cldrv->driver.owner = owner; 1238 cldrv->driver.bus = &mei_cl_bus_type; 1239 1240 err = driver_register(&cldrv->driver); 1241 if (err) 1242 return err; 1243 1244 pr_debug("mei: driver [%s] registered\n", cldrv->driver.name); 1245 1246 return 0; 1247 } 1248 EXPORT_SYMBOL_GPL(__mei_cldev_driver_register); 1249 1250 void mei_cldev_driver_unregister(struct mei_cl_driver *cldrv) 1251 { 1252 driver_unregister(&cldrv->driver); 1253 1254 pr_debug("mei: driver [%s] unregistered\n", cldrv->driver.name); 1255 } 1256 EXPORT_SYMBOL_GPL(mei_cldev_driver_unregister); 1257 1258 1259 int __init mei_cl_bus_init(void) 1260 { 1261 return bus_register(&mei_cl_bus_type); 1262 } 1263 1264 void __exit mei_cl_bus_exit(void) 1265 { 1266 bus_unregister(&mei_cl_bus_type); 1267 } 1268