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