drivers/misc/mei/bus.c

   1 /*
   2  * Intel Management Engine Interface (Intel MEI) Linux driver
   3  * Copyright (c) 2012-2013, Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/device.h>
  18 #include <linux/kernel.h>
  19 #include <linux/sched.h>
  20 #include <linux/init.h>
  21 #include <linux/errno.h>
  22 #include <linux/slab.h>
  23 #include <linux/mutex.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/mei_cl_bus.h>
  26
  27 #include "mei_dev.h"
  28 #include "client.h"
  29
  30 #define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver)
  31 #define to_mei_cl_device(d) container_of(d, struct mei_cl_device, dev)
  32
  33 /**
  34  * __mei_cl_send - internal client send (write)
  35  *
  36  * @cl: host client
  37  * @buf: buffer to send
  38  * @length: buffer length
  39  * @blocking: wait for write completion
  40  *
  41  * Return: written size bytes or < 0 on error
  42  */
  43 ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
  44                         bool blocking)
  45 {
  46         struct mei_device *bus;
  47         struct mei_cl_cb *cb;
  48         ssize_t rets;
  49
  50         if (WARN_ON(!cl || !cl->dev))
  51                 return -ENODEV;
  52
  53         bus = cl->dev;
  54
  55         mutex_lock(&bus->device_lock);
  56         if (bus->dev_state != MEI_DEV_ENABLED) {
  57                 rets = -ENODEV;
  58                 goto out;
  59         }
  60
  61         if (!mei_cl_is_connected(cl)) {
  62                 rets = -ENODEV;
  63                 goto out;
  64         }
  65
  66         /* Check if we have an ME client device */
  67         if (!mei_me_cl_is_active(cl->me_cl)) {
  68                 rets = -ENOTTY;
  69                 goto out;
  70         }
  71
  72         if (length > mei_cl_mtu(cl)) {
  73                 rets = -EFBIG;
  74                 goto out;
  75         }
  76
  77         cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, NULL);
  78         if (!cb) {
  79                 rets = -ENOMEM;
  80                 goto out;
  81         }
  82
  83         memcpy(cb->buf.data, buf, length);
  84
  85         rets = mei_cl_write(cl, cb, blocking);
  86
  87 out:
  88         mutex_unlock(&bus->device_lock);
  89
  90         return rets;
  91 }
  92
  93 /**
  94  * __mei_cl_recv - internal client receive (read)
  95  *
  96  * @cl: host client
  97  * @buf: buffer to receive
  98  * @length: buffer length
  99  *
 100  * Return: read size in bytes of < 0 on error
 101  */
 102 ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 103 {
 104         struct mei_device *bus;
 105         struct mei_cl_cb *cb;
 106         size_t r_length;
 107         ssize_t rets;
 108
 109         if (WARN_ON(!cl || !cl->dev))
 110                 return -ENODEV;
 111
 112         bus = cl->dev;
 113
 114         mutex_lock(&bus->device_lock);
 115         if (bus->dev_state != MEI_DEV_ENABLED) {
 116                 rets = -ENODEV;
 117                 goto out;
 118         }
 119
 120         cb = mei_cl_read_cb(cl, NULL);
 121         if (cb)
 122                 goto copy;
 123
 124         rets = mei_cl_read_start(cl, length, NULL);
 125         if (rets && rets != -EBUSY)
 126                 goto out;
 127
 128         /* wait on event only if there is no other waiter */
 129         if (list_empty(&cl->rd_completed) && !waitqueue_active(&cl->rx_wait)) {
 130
 131                 mutex_unlock(&bus->device_lock);
 132
 133                 if (wait_event_interruptible(cl->rx_wait,
 134                                 (!list_empty(&cl->rd_completed)) ||
 135                                 (!mei_cl_is_connected(cl)))) {
 136
 137                         if (signal_pending(current))
 138                                 return -EINTR;
 139                         return -ERESTARTSYS;
 140                 }
 141
 142                 mutex_lock(&bus->device_lock);
 143
 144                 if (!mei_cl_is_connected(cl)) {
 145                         rets = -EBUSY;
 146                         goto out;
 147                 }
 148         }
 149
 150         cb = mei_cl_read_cb(cl, NULL);
 151         if (!cb) {
 152                 rets = 0;
 153                 goto out;
 154         }
 155
 156 copy:
 157         if (cb->status) {
 158                 rets = cb->status;
 159                 goto free;
 160         }
 161
 162         r_length = min_t(size_t, length, cb->buf_idx);
 163         memcpy(buf, cb->buf.data, r_length);
 164         rets = r_length;
 165
 166 free:
 167         mei_io_cb_free(cb);
 168 out:
 169         mutex_unlock(&bus->device_lock);
 170
 171         return rets;
 172 }
 173
 174 /**
 175  * mei_cldev_send - me device send  (write)
 176  *
 177  * @cldev: me client device
 178  * @buf: buffer to send
 179  * @length: buffer length
 180  *
 181  * Return: written size in bytes or < 0 on error
 182  */
 183 ssize_t mei_cldev_send(struct mei_cl_device *cldev, u8 *buf, size_t length)
 184 {
 185         struct mei_cl *cl = cldev->cl;
 186
 187         if (cl == NULL)
 188                 return -ENODEV;
 189
 190         return __mei_cl_send(cl, buf, length, 1);
 191 }
 192 EXPORT_SYMBOL_GPL(mei_cldev_send);
 193
 194 /**
 195  * mei_cldev_recv - client receive (read)
 196  *
 197  * @cldev: me client device
 198  * @buf: buffer to receive
 199  * @length: buffer length
 200  *
 201  * Return: read size in bytes of < 0 on error
 202  */
 203 ssize_t mei_cldev_recv(struct mei_cl_device *cldev, u8 *buf, size_t length)
 204 {
 205         struct mei_cl *cl = cldev->cl;
 206
 207         if (cl == NULL)
 208                 return -ENODEV;
 209
 210         return __mei_cl_recv(cl, buf, length);
 211 }
 212 EXPORT_SYMBOL_GPL(mei_cldev_recv);
 213
 214 /**
 215  * mei_cl_bus_event_work  - dispatch rx event for a bus device
 216  *    and schedule new work
 217  *
 218  * @work: work
 219  */
 220 static void mei_cl_bus_event_work(struct work_struct *work)
 221 {
 222         struct mei_cl_device *cldev;
 223         struct mei_device *bus;
 224
 225         cldev = container_of(work, struct mei_cl_device, event_work);
 226
 227         bus = cldev->bus;
 228
 229         if (cldev->event_cb)
 230                 cldev->event_cb(cldev, cldev->events, cldev->event_context);
 231
 232         cldev->events = 0;
 233
 234         /* Prepare for the next read */
 235         if (cldev->events_mask & BIT(MEI_CL_EVENT_RX)) {
 236                 mutex_lock(&bus->device_lock);
 237                 mei_cl_read_start(cldev->cl, 0, NULL);
 238                 mutex_unlock(&bus->device_lock);
 239         }
 240 }
 241
 242 /**
 243  * mei_cl_bus_notify_event - schedule notify cb on bus client
 244  *
 245  * @cl: host client
 246  *
 247  * Return: true if event was scheduled
 248  *         false if the client is not waiting for event
 249  */
 250 bool mei_cl_bus_notify_event(struct mei_cl *cl)
 251 {
 252         struct mei_cl_device *cldev = cl->cldev;
 253
 254         if (!cldev || !cldev->event_cb)
 255                 return false;
 256
 257         if (!(cldev->events_mask & BIT(MEI_CL_EVENT_NOTIF)))
 258                 return false;
 259
 260         if (!cl->notify_ev)
 261                 return false;
 262
 263         set_bit(MEI_CL_EVENT_NOTIF, &cldev->events);
 264
 265         schedule_work(&cldev->event_work);
 266
 267         cl->notify_ev = false;
 268
 269         return true;
 270 }
 271
 272 /**
 273  * mei_cl_bus_rx_event  - schedule rx event
 274  *
 275  * @cl: host client
 276  *
 277  * Return: true if event was scheduled
 278  *         false if the client is not waiting for event
 279  */
 280 bool mei_cl_bus_rx_event(struct mei_cl *cl)
 281 {
 282         struct mei_cl_device *cldev = cl->cldev;
 283
 284         if (!cldev || !cldev->event_cb)
 285                 return false;
 286
 287         if (!(cldev->events_mask & BIT(MEI_CL_EVENT_RX)))
 288                 return false;
 289
 290         set_bit(MEI_CL_EVENT_RX, &cldev->events);
 291
 292         schedule_work(&cldev->event_work);
 293
 294         return true;
 295 }
 296
 297 /**
 298  * mei_cldev_register_event_cb - register event callback
 299  *
 300  * @cldev: me client devices
 301  * @event_cb: callback function
 302  * @events_mask: requested events bitmask
 303  * @context: driver context data
 304  *
 305  * Return: 0 on success
 306  *         -EALREADY if an callback is already registered
 307  *         <0 on other errors
 308  */
 309 int mei_cldev_register_event_cb(struct mei_cl_device *cldev,
 310                                 unsigned long events_mask,
 311                                 mei_cldev_event_cb_t event_cb, void *context)
 312 {
 313         struct mei_device *bus = cldev->bus;
 314         int ret;
 315
 316         if (cldev->event_cb)
 317                 return -EALREADY;
 318
 319         cldev->events = 0;
 320         cldev->events_mask = events_mask;
 321         cldev->event_cb = event_cb;
 322         cldev->event_context = context;
 323         INIT_WORK(&cldev->event_work, mei_cl_bus_event_work);
 324
 325         if (cldev->events_mask & BIT(MEI_CL_EVENT_RX)) {
 326                 mutex_lock(&bus->device_lock);
 327                 ret = mei_cl_read_start(cldev->cl, 0, NULL);
 328                 mutex_unlock(&bus->device_lock);
 329                 if (ret && ret != -EBUSY)
 330                         return ret;
 331         }
 332
 333         if (cldev->events_mask & BIT(MEI_CL_EVENT_NOTIF)) {
 334                 mutex_lock(&bus->device_lock);
 335                 ret = mei_cl_notify_request(cldev->cl, NULL, event_cb ? 1 : 0);
 336                 mutex_unlock(&bus->device_lock);
 337                 if (ret)
 338                         return ret;
 339         }
 340
 341         return 0;
 342 }
 343 EXPORT_SYMBOL_GPL(mei_cldev_register_event_cb);
 344
 345 /**
 346  * mei_cldev_get_drvdata - driver data getter
 347  *
 348  * @cldev: mei client device
 349  *
 350  * Return: driver private data
 351  */
 352 void *mei_cldev_get_drvdata(const struct mei_cl_device *cldev)
 353 {
 354         return dev_get_drvdata(&cldev->dev);
 355 }
 356 EXPORT_SYMBOL_GPL(mei_cldev_get_drvdata);
 357
 358 /**
 359  * mei_cldev_set_drvdata - driver data setter
 360  *
 361  * @cldev: mei client device
 362  * @data: data to store
 363  */
 364 void mei_cldev_set_drvdata(struct mei_cl_device *cldev, void *data)
 365 {
 366         dev_set_drvdata(&cldev->dev, data);
 367 }
 368 EXPORT_SYMBOL_GPL(mei_cldev_set_drvdata);
 369
 370 /**
 371  * mei_cldev_uuid - return uuid of the underlying me client
 372  *
 373  * @cldev: mei client device
 374  *
 375  * Return: me client uuid
 376  */
 377 const uuid_le *mei_cldev_uuid(const struct mei_cl_device *cldev)
 378 {
 379         return mei_me_cl_uuid(cldev->me_cl);
 380 }
 381 EXPORT_SYMBOL_GPL(mei_cldev_uuid);
 382
 383 /**
 384  * mei_cldev_ver - return protocol version of the underlying me client
 385  *
 386  * @cldev: mei client device
 387  *
 388  * Return: me client protocol version
 389  */
 390 u8 mei_cldev_ver(const struct mei_cl_device *cldev)
 391 {
 392         return mei_me_cl_ver(cldev->me_cl);
 393 }
 394 EXPORT_SYMBOL_GPL(mei_cldev_ver);
 395
 396 /**
 397  * mei_cldev_enabled - check whether the device is enabled
 398  *
 399  * @cldev: mei client device
 400  *
 401  * Return: true if me client is initialized and connected
 402  */
 403 bool mei_cldev_enabled(struct mei_cl_device *cldev)
 404 {
 405         return cldev->cl && mei_cl_is_connected(cldev->cl);
 406 }
 407 EXPORT_SYMBOL_GPL(mei_cldev_enabled);
 408
 409 /**
 410  * mei_cldev_enable_device - enable me client device
 411  *     create connection with me client
 412  *
 413  * @cldev: me client device
 414  *
 415  * Return: 0 on success and < 0 on error
 416  */
 417 int mei_cldev_enable(struct mei_cl_device *cldev)
 418 {
 419         struct mei_device *bus = cldev->bus;
 420         struct mei_cl *cl;
 421         int ret;
 422
 423         cl = cldev->cl;
 424
 425         if (!cl) {
 426                 mutex_lock(&bus->device_lock);
 427                 cl = mei_cl_alloc_linked(bus);
 428                 mutex_unlock(&bus->device_lock);
 429                 if (IS_ERR(cl))
 430                         return PTR_ERR(cl);
 431                 /* update pointers */
 432                 cldev->cl = cl;
 433                 cl->cldev = cldev;
 434         }
 435
 436         mutex_lock(&bus->device_lock);
 437         if (mei_cl_is_connected(cl)) {
 438                 ret = 0;
 439                 goto out;
 440         }
 441
 442         if (!mei_me_cl_is_active(cldev->me_cl)) {
 443                 dev_err(&cldev->dev, "me client is not active\n");
 444                 ret = -ENOTTY;
 445                 goto out;
 446         }
 447
 448         ret = mei_cl_connect(cl, cldev->me_cl, NULL);
 449         if (ret < 0)
 450                 dev_err(&cldev->dev, "cannot connect\n");
 451
 452 out:
 453         mutex_unlock(&bus->device_lock);
 454
 455         return ret;
 456 }
 457 EXPORT_SYMBOL_GPL(mei_cldev_enable);
 458
 459 /**
 460  * mei_cldev_disable - disable me client device
 461  *     disconnect form the me client
 462  *
 463  * @cldev: me client device
 464  *
 465  * Return: 0 on success and < 0 on error
 466  */
 467 int mei_cldev_disable(struct mei_cl_device *cldev)
 468 {
 469         struct mei_device *bus;
 470         struct mei_cl *cl;
 471         int err;
 472
 473         if (!cldev || !cldev->cl)
 474                 return -ENODEV;
 475
 476         cl = cldev->cl;
 477
 478         bus = cldev->bus;
 479
 480         cldev->event_cb = NULL;
 481
 482         mutex_lock(&bus->device_lock);
 483
 484         if (!mei_cl_is_connected(cl)) {
 485                 dev_err(bus->dev, "Already disconnected");
 486                 err = 0;
 487                 goto out;
 488         }
 489
 490         err = mei_cl_disconnect(cl);
 491         if (err < 0)
 492                 dev_err(bus->dev, "Could not disconnect from the ME client");
 493
 494 out:
 495         /* Flush queues and remove any pending read */
 496         mei_cl_flush_queues(cl, NULL);
 497         mei_cl_unlink(cl);
 498
 499         kfree(cl);
 500         cldev->cl = NULL;
 501
 502         mutex_unlock(&bus->device_lock);
 503         return err;
 504 }
 505 EXPORT_SYMBOL_GPL(mei_cldev_disable);
 506
 507 /**
 508  * mei_cl_device_find - find matching entry in the driver id table
 509  *
 510  * @cldev: me client device
 511  * @cldrv: me client driver
 512  *
 513  * Return: id on success; NULL if no id is matching
 514  */
 515 static const
 516 struct mei_cl_device_id *mei_cl_device_find(struct mei_cl_device *cldev,
 517                                             struct mei_cl_driver *cldrv)
 518 {
 519         const struct mei_cl_device_id *id;
 520         const uuid_le *uuid;
 521         u8 version;
 522         bool match;
 523
 524         uuid = mei_me_cl_uuid(cldev->me_cl);
 525         version = mei_me_cl_ver(cldev->me_cl);
 526
 527         id = cldrv->id_table;
 528         while (uuid_le_cmp(NULL_UUID_LE, id->uuid)) {
 529                 if (!uuid_le_cmp(*uuid, id->uuid)) {
 530                         match = true;
 531
 532                         if (cldev->name[0])
 533                                 if (strncmp(cldev->name, id->name,
 534                                             sizeof(id->name)))
 535                                         match = false;
 536
 537                         if (id->version != MEI_CL_VERSION_ANY)
 538                                 if (id->version != version)
 539                                         match = false;
 540                         if (match)
 541                                 return id;
 542                 }
 543
 544                 id++;
 545         }
 546
 547         return NULL;
 548 }
 549
 550 /**
 551  * mei_cl_device_match  - device match function
 552  *
 553  * @dev: device
 554  * @drv: driver
 555  *
 556  * Return:  1 if matching device was found 0 otherwise
 557  */
 558 static int mei_cl_device_match(struct device *dev, struct device_driver *drv)
 559 {
 560         struct mei_cl_device *cldev = to_mei_cl_device(dev);
 561         struct mei_cl_driver *cldrv = to_mei_cl_driver(drv);
 562         const struct mei_cl_device_id *found_id;
 563
 564         if (!cldev)
 565                 return 0;
 566
 567         if (!cldev->do_match)
 568                 return 0;
 569
 570         if (!cldrv || !cldrv->id_table)
 571                 return 0;
 572
 573         found_id = mei_cl_device_find(cldev, cldrv);
 574         if (found_id)
 575                 return 1;
 576
 577         return 0;
 578 }
 579
 580 /**
 581  * mei_cl_device_probe - bus probe function
 582  *
 583  * @dev: device
 584  *
 585  * Return:  0 on success; < 0 otherwise
 586  */
 587 static int mei_cl_device_probe(struct device *dev)
 588 {
 589         struct mei_cl_device *cldev;
 590         struct mei_cl_driver *cldrv;
 591         const struct mei_cl_device_id *id;
 592         int ret;
 593
 594         cldev = to_mei_cl_device(dev);
 595         cldrv = to_mei_cl_driver(dev->driver);
 596
 597         if (!cldev)
 598                 return 0;
 599
 600         if (!cldrv || !cldrv->probe)
 601                 return -ENODEV;
 602
 603         id = mei_cl_device_find(cldev, cldrv);
 604         if (!id)
 605                 return -ENODEV;
 606
 607         ret = cldrv->probe(cldev, id);
 608         if (ret)
 609                 return ret;
 610
 611         __module_get(THIS_MODULE);
 612         return 0;
 613 }
 614
 615 /**
 616  * mei_cl_device_remove - remove device from the bus
 617  *
 618  * @dev: device
 619  *
 620  * Return:  0 on success; < 0 otherwise
 621  */
 622 static int mei_cl_device_remove(struct device *dev)
 623 {
 624         struct mei_cl_device *cldev = to_mei_cl_device(dev);
 625         struct mei_cl_driver *cldrv;
 626         int ret = 0;
 627
 628         if (!cldev || !dev->driver)
 629                 return 0;
 630
 631         if (cldev->event_cb) {
 632                 cldev->event_cb = NULL;
 633                 cancel_work_sync(&cldev->event_work);
 634         }
 635
 636         cldrv = to_mei_cl_driver(dev->driver);
 637         if (cldrv->remove)
 638                 ret = cldrv->remove(cldev);
 639
 640         module_put(THIS_MODULE);
 641         dev->driver = NULL;
 642         return ret;
 643
 644 }
 645
 646 static ssize_t name_show(struct device *dev, struct device_attribute *a,
 647                              char *buf)
 648 {
 649         struct mei_cl_device *cldev = to_mei_cl_device(dev);
 650
 651         return scnprintf(buf, PAGE_SIZE, "%s", cldev->name);
 652 }
 653 static DEVICE_ATTR_RO(name);
 654
 655 static ssize_t uuid_show(struct device *dev, struct device_attribute *a,
 656                              char *buf)
 657 {
 658         struct mei_cl_device *cldev = to_mei_cl_device(dev);
 659         const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
 660
 661         return scnprintf(buf, PAGE_SIZE, "%pUl", uuid);
 662 }
 663 static DEVICE_ATTR_RO(uuid);
 664
 665 static ssize_t version_show(struct device *dev, struct device_attribute *a,
 666                              char *buf)
 667 {
 668         struct mei_cl_device *cldev = to_mei_cl_device(dev);
 669         u8 version = mei_me_cl_ver(cldev->me_cl);
 670
 671         return scnprintf(buf, PAGE_SIZE, "%02X", version);
 672 }
 673 static DEVICE_ATTR_RO(version);
 674
 675 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 676                              char *buf)
 677 {
 678         struct mei_cl_device *cldev = to_mei_cl_device(dev);
 679         const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
 680
 681         return scnprintf(buf, PAGE_SIZE, "mei:%s:%pUl:", cldev->name, uuid);
 682 }
 683 static DEVICE_ATTR_RO(modalias);
 684
 685 static struct attribute *mei_cldev_attrs[] = {
 686         &dev_attr_name.attr,
 687         &dev_attr_uuid.attr,
 688         &dev_attr_version.attr,
 689         &dev_attr_modalias.attr,
 690         NULL,
 691 };
 692 ATTRIBUTE_GROUPS(mei_cldev);
 693
 694 /**
 695  * mei_cl_device_uevent - me client bus uevent handler
 696  *
 697  * @dev: device
 698  * @env: uevent kobject
 699  *
 700  * Return: 0 on success -ENOMEM on when add_uevent_var fails
 701  */
 702 static int mei_cl_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 703 {
 704         struct mei_cl_device *cldev = to_mei_cl_device(dev);
 705         const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
 706         u8 version = mei_me_cl_ver(cldev->me_cl);
 707
 708         if (add_uevent_var(env, "MEI_CL_VERSION=%d", version))
 709                 return -ENOMEM;
 710
 711         if (add_uevent_var(env, "MEI_CL_UUID=%pUl", uuid))
 712                 return -ENOMEM;
 713
 714         if (add_uevent_var(env, "MEI_CL_NAME=%s", cldev->name))
 715                 return -ENOMEM;
 716
 717         if (add_uevent_var(env, "MODALIAS=mei:%s:%pUl:%02X:",
 718                            cldev->name, uuid, version))
 719                 return -ENOMEM;
 720
 721         return 0;
 722 }
 723
 724 static struct bus_type mei_cl_bus_type = {
 725         .name           = "mei",
 726         .dev_groups     = mei_cldev_groups,
 727         .match          = mei_cl_device_match,
 728         .probe          = mei_cl_device_probe,
 729         .remove         = mei_cl_device_remove,
 730         .uevent         = mei_cl_device_uevent,
 731 };
 732
 733 static struct mei_device *mei_dev_bus_get(struct mei_device *bus)
 734 {
 735         if (bus)
 736                 get_device(bus->dev);
 737
 738         return bus;
 739 }
 740
 741 static void mei_dev_bus_put(struct mei_device *bus)
 742 {
 743         if (bus)
 744                 put_device(bus->dev);
 745 }
 746
 747 static void mei_cl_bus_dev_release(struct device *dev)
 748 {
 749         struct mei_cl_device *cldev = to_mei_cl_device(dev);
 750
 751         if (!cldev)
 752                 return;
 753
 754         mei_me_cl_put(cldev->me_cl);
 755         mei_dev_bus_put(cldev->bus);
 756         kfree(cldev);
 757 }
 758
 759 static struct device_type mei_cl_device_type = {
 760         .release        = mei_cl_bus_dev_release,
 761 };
 762
 763 /**
 764  * mei_cl_bus_set_name - set device name for me client device
 765  *
 766  * @cldev: me client device
 767  */
 768 static inline void mei_cl_bus_set_name(struct mei_cl_device *cldev)
 769 {
 770         dev_set_name(&cldev->dev, "mei:%s:%pUl:%02X",
 771                      cldev->name,
 772                      mei_me_cl_uuid(cldev->me_cl),
 773                      mei_me_cl_ver(cldev->me_cl));
 774 }
 775
 776 /**
 777  * mei_cl_bus_dev_alloc - initialize and allocate mei client device
 778  *
 779  * @bus: mei device
 780  * @me_cl: me client
 781  *
 782  * Return: allocated device structur or NULL on allocation failure
 783  */
 784 static struct mei_cl_device *mei_cl_bus_dev_alloc(struct mei_device *bus,
 785                                                   struct mei_me_client *me_cl)
 786 {
 787         struct mei_cl_device *cldev;
 788
 789         cldev = kzalloc(sizeof(struct mei_cl_device), GFP_KERNEL);
 790         if (!cldev)
 791                 return NULL;
 792
 793         device_initialize(&cldev->dev);
 794         cldev->dev.parent = bus->dev;
 795         cldev->dev.bus    = &mei_cl_bus_type;
 796         cldev->dev.type   = &mei_cl_device_type;
 797         cldev->bus        = mei_dev_bus_get(bus);
 798         cldev->me_cl      = mei_me_cl_get(me_cl);
 799         mei_cl_bus_set_name(cldev);
 800         cldev->is_added   = 0;
 801         INIT_LIST_HEAD(&cldev->bus_list);
 802
 803         return cldev;
 804 }
 805
 806 /**
 807  * mei_cl_dev_setup - setup me client device
 808  *    run fix up routines and set the device name
 809  *
 810  * @bus: mei device
 811  * @cldev: me client device
 812  *
 813  * Return: true if the device is eligible for enumeration
 814  */
 815 static bool mei_cl_bus_dev_setup(struct mei_device *bus,
 816                                  struct mei_cl_device *cldev)
 817 {
 818         cldev->do_match = 1;
 819         mei_cl_bus_dev_fixup(cldev);
 820
 821         /* the device name can change during fix up */
 822         if (cldev->do_match)
 823                 mei_cl_bus_set_name(cldev);
 824
 825         return cldev->do_match == 1;
 826 }
 827
 828 /**
 829  * mei_cl_bus_dev_add - add me client devices
 830  *
 831  * @cldev: me client device
 832  *
 833  * Return: 0 on success; < 0 on failre
 834  */
 835 static int mei_cl_bus_dev_add(struct mei_cl_device *cldev)
 836 {
 837         int ret;
 838
 839         dev_dbg(cldev->bus->dev, "adding %pUL:%02X\n",
 840                 mei_me_cl_uuid(cldev->me_cl),
 841                 mei_me_cl_ver(cldev->me_cl));
 842         ret = device_add(&cldev->dev);
 843         if (!ret)
 844                 cldev->is_added = 1;
 845
 846         return ret;
 847 }
 848
 849 /**
 850  * mei_cl_bus_dev_stop - stop the driver
 851  *
 852  * @cldev: me client device
 853  */
 854 static void mei_cl_bus_dev_stop(struct mei_cl_device *cldev)
 855 {
 856         if (cldev->is_added)
 857                 device_release_driver(&cldev->dev);
 858 }
 859
 860 /**
 861  * mei_cl_bus_dev_destroy - destroy me client devices object
 862  *
 863  * @cldev: me client device
 864  *
 865  * Locking: called under "dev->cl_bus_lock" lock
 866  */
 867 static void mei_cl_bus_dev_destroy(struct mei_cl_device *cldev)
 868 {
 869
 870         WARN_ON(!mutex_is_locked(&cldev->bus->cl_bus_lock));
 871
 872         if (!cldev->is_added)
 873                 return;
 874
 875         device_del(&cldev->dev);
 876
 877         list_del_init(&cldev->bus_list);
 878
 879         cldev->is_added = 0;
 880         put_device(&cldev->dev);
 881 }
 882
 883 /**
 884  * mei_cl_bus_remove_device - remove a devices form the bus
 885  *
 886  * @cldev: me client device
 887  */
 888 static void mei_cl_bus_remove_device(struct mei_cl_device *cldev)
 889 {
 890         mei_cl_bus_dev_stop(cldev);
 891         mei_cl_bus_dev_destroy(cldev);
 892 }
 893
 894 /**
 895  * mei_cl_bus_remove_devices - remove all devices form the bus
 896  *
 897  * @bus: mei device
 898  */
 899 void mei_cl_bus_remove_devices(struct mei_device *bus)
 900 {
 901         struct mei_cl_device *cldev, *next;
 902
 903         mutex_lock(&bus->cl_bus_lock);
 904         list_for_each_entry_safe(cldev, next, &bus->device_list, bus_list)
 905                 mei_cl_bus_remove_device(cldev);
 906         mutex_unlock(&bus->cl_bus_lock);
 907 }
 908
 909
 910 /**
 911  * mei_cl_bus_dev_init - allocate and initializes an mei client devices
 912  *     based on me client
 913  *
 914  * @bus: mei device
 915  * @me_cl: me client
 916  *
 917  * Locking: called under "dev->cl_bus_lock" lock
 918  */
 919 static void mei_cl_bus_dev_init(struct mei_device *bus,
 920                                 struct mei_me_client *me_cl)
 921 {
 922         struct mei_cl_device *cldev;
 923
 924         WARN_ON(!mutex_is_locked(&bus->cl_bus_lock));
 925
 926         dev_dbg(bus->dev, "initializing %pUl", mei_me_cl_uuid(me_cl));
 927
 928         if (me_cl->bus_added)
 929                 return;
 930
 931         cldev = mei_cl_bus_dev_alloc(bus, me_cl);
 932         if (!cldev)
 933                 return;
 934
 935         me_cl->bus_added = true;
 936         list_add_tail(&cldev->bus_list, &bus->device_list);
 937
 938 }
 939
 940 /**
 941  * mei_cl_bus_rescan - scan me clients list and add create
 942  *    devices for eligible clients
 943  *
 944  * @bus: mei device
 945  */
 946 void mei_cl_bus_rescan(struct mei_device *bus)
 947 {
 948         struct mei_cl_device *cldev, *n;
 949         struct mei_me_client *me_cl;
 950
 951         mutex_lock(&bus->cl_bus_lock);
 952
 953         down_read(&bus->me_clients_rwsem);
 954         list_for_each_entry(me_cl, &bus->me_clients, list)
 955                 mei_cl_bus_dev_init(bus, me_cl);
 956         up_read(&bus->me_clients_rwsem);
 957
 958         list_for_each_entry_safe(cldev, n, &bus->device_list, bus_list) {
 959
 960                 if (!mei_me_cl_is_active(cldev->me_cl)) {
 961                         mei_cl_bus_remove_device(cldev);
 962                         continue;
 963                 }
 964
 965                 if (cldev->is_added)
 966                         continue;
 967
 968                 if (mei_cl_bus_dev_setup(bus, cldev))
 969                         mei_cl_bus_dev_add(cldev);
 970                 else {
 971                         list_del_init(&cldev->bus_list);
 972                         put_device(&cldev->dev);
 973                 }
 974         }
 975         mutex_unlock(&bus->cl_bus_lock);
 976
 977         dev_dbg(bus->dev, "rescan end");
 978 }
 979
 980 void mei_cl_bus_rescan_work(struct work_struct *work)
 981 {
 982         struct mei_device *bus =
 983                 container_of(work, struct mei_device, bus_rescan_work);
 984         struct mei_me_client *me_cl;
 985
 986         mutex_lock(&bus->device_lock);
 987         me_cl = mei_me_cl_by_uuid(bus, &mei_amthif_guid);
 988         if (me_cl)
 989                 mei_amthif_host_init(bus, me_cl);
 990         mei_me_cl_put(me_cl);
 991         mutex_unlock(&bus->device_lock);
 992
 993         mei_cl_bus_rescan(bus);
 994 }
 995
 996 int __mei_cldev_driver_register(struct mei_cl_driver *cldrv,
 997                                 struct module *owner)
 998 {
 999         int err;
1000
1001         cldrv->driver.name = cldrv->name;
1002         cldrv->driver.owner = owner;
1003         cldrv->driver.bus = &mei_cl_bus_type;
1004
1005         err = driver_register(&cldrv->driver);
1006         if (err)
1007                 return err;
1008
1009         pr_debug("mei: driver [%s] registered\n", cldrv->driver.name);
1010
1011         return 0;
1012 }
1013 EXPORT_SYMBOL_GPL(__mei_cldev_driver_register);
1014
1015 void mei_cldev_driver_unregister(struct mei_cl_driver *cldrv)
1016 {
1017         driver_unregister(&cldrv->driver);
1018
1019         pr_debug("mei: driver [%s] unregistered\n", cldrv->driver.name);
1020 }
1021 EXPORT_SYMBOL_GPL(mei_cldev_driver_unregister);
1022
1023
1024 int __init mei_cl_bus_init(void)
1025 {
1026         return bus_register(&mei_cl_bus_type);
1027 }
1028
1029 void __exit mei_cl_bus_exit(void)
1030 {
1031         bus_unregister(&mei_cl_bus_type);
1032 }