drivers/gpu/host1x/bus.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2012 Avionic Design GmbH
   4  * Copyright (C) 2012-2013, NVIDIA Corporation
   5  */
   6
   7 #include <linux/debugfs.h>
   8 #include <linux/host1x.h>
   9 #include <linux/of.h>
  10 #include <linux/seq_file.h>
  11 #include <linux/slab.h>
  12 #include <linux/of_device.h>
  13
  14 #include "bus.h"
  15 #include "dev.h"
  16
  17 static DEFINE_MUTEX(clients_lock);
  18 static LIST_HEAD(clients);
  19
  20 static DEFINE_MUTEX(drivers_lock);
  21 static LIST_HEAD(drivers);
  22
  23 static DEFINE_MUTEX(devices_lock);
  24 static LIST_HEAD(devices);
  25
  26 struct host1x_subdev {
  27         struct host1x_client *client;
  28         struct device_node *np;
  29         struct list_head list;
  30 };
  31
  32 /**
  33  * host1x_subdev_add() - add a new subdevice with an associated device node
  34  * @device: host1x device to add the subdevice to
  35  * @driver: host1x driver containing the subdevices
  36  * @np: device node
  37  */
  38 static int host1x_subdev_add(struct host1x_device *device,
  39                              struct host1x_driver *driver,
  40                              struct device_node *np)
  41 {
  42         struct host1x_subdev *subdev;
  43         struct device_node *child;
  44         int err;
  45
  46         subdev = kzalloc(sizeof(*subdev), GFP_KERNEL);
  47         if (!subdev)
  48                 return -ENOMEM;
  49
  50         INIT_LIST_HEAD(&subdev->list);
  51         subdev->np = of_node_get(np);
  52
  53         mutex_lock(&device->subdevs_lock);
  54         list_add_tail(&subdev->list, &device->subdevs);
  55         mutex_unlock(&device->subdevs_lock);
  56
  57         /* recursively add children */
  58         for_each_child_of_node(np, child) {
  59                 if (of_match_node(driver->subdevs, child) &&
  60                     of_device_is_available(child)) {
  61                         err = host1x_subdev_add(device, driver, child);
  62                         if (err < 0) {
  63                                 /* XXX cleanup? */
  64                                 of_node_put(child);
  65                                 return err;
  66                         }
  67                 }
  68         }
  69
  70         return 0;
  71 }
  72
  73 /**
  74  * host1x_subdev_del() - remove subdevice
  75  * @subdev: subdevice to remove
  76  */
  77 static void host1x_subdev_del(struct host1x_subdev *subdev)
  78 {
  79         list_del(&subdev->list);
  80         of_node_put(subdev->np);
  81         kfree(subdev);
  82 }
  83
  84 /**
  85  * host1x_device_parse_dt() - scan device tree and add matching subdevices
  86  * @device: host1x logical device
  87  * @driver: host1x driver
  88  */
  89 static int host1x_device_parse_dt(struct host1x_device *device,
  90                                   struct host1x_driver *driver)
  91 {
  92         struct device_node *np;
  93         int err;
  94
  95         for_each_child_of_node(device->dev.parent->of_node, np) {
  96                 if (of_match_node(driver->subdevs, np) &&
  97                     of_device_is_available(np)) {
  98                         err = host1x_subdev_add(device, driver, np);
  99                         if (err < 0) {
 100                                 of_node_put(np);
 101                                 return err;
 102                         }
 103                 }
 104         }
 105
 106         return 0;
 107 }
 108
 109 static void host1x_subdev_register(struct host1x_device *device,
 110                                    struct host1x_subdev *subdev,
 111                                    struct host1x_client *client)
 112 {
 113         int err;
 114
 115         /*
 116          * Move the subdevice to the list of active (registered) subdevices
 117          * and associate it with a client. At the same time, associate the
 118          * client with its parent device.
 119          */
 120         mutex_lock(&device->subdevs_lock);
 121         mutex_lock(&device->clients_lock);
 122         list_move_tail(&client->list, &device->clients);
 123         list_move_tail(&subdev->list, &device->active);
 124         client->host = &device->dev;
 125         subdev->client = client;
 126         mutex_unlock(&device->clients_lock);
 127         mutex_unlock(&device->subdevs_lock);
 128
 129         if (list_empty(&device->subdevs)) {
 130                 err = device_add(&device->dev);
 131                 if (err < 0)
 132                         dev_err(&device->dev, "failed to add: %d\n", err);
 133                 else
 134                         device->registered = true;
 135         }
 136 }
 137
 138 static void __host1x_subdev_unregister(struct host1x_device *device,
 139                                        struct host1x_subdev *subdev)
 140 {
 141         struct host1x_client *client = subdev->client;
 142
 143         /*
 144          * If all subdevices have been activated, we're about to remove the
 145          * first active subdevice, so unload the driver first.
 146          */
 147         if (list_empty(&device->subdevs)) {
 148                 if (device->registered) {
 149                         device->registered = false;
 150                         device_del(&device->dev);
 151                 }
 152         }
 153
 154         /*
 155          * Move the subdevice back to the list of idle subdevices and remove
 156          * it from list of clients.
 157          */
 158         mutex_lock(&device->clients_lock);
 159         subdev->client = NULL;
 160         client->host = NULL;
 161         list_move_tail(&subdev->list, &device->subdevs);
 162         /*
 163          * XXX: Perhaps don't do this here, but rather explicitly remove it
 164          * when the device is about to be deleted.
 165          *
 166          * This is somewhat complicated by the fact that this function is
 167          * used to remove the subdevice when a client is unregistered but
 168          * also when the composite device is about to be removed.
 169          */
 170         list_del_init(&client->list);
 171         mutex_unlock(&device->clients_lock);
 172 }
 173
 174 static void host1x_subdev_unregister(struct host1x_device *device,
 175                                      struct host1x_subdev *subdev)
 176 {
 177         mutex_lock(&device->subdevs_lock);
 178         __host1x_subdev_unregister(device, subdev);
 179         mutex_unlock(&device->subdevs_lock);
 180 }
 181
 182 /**
 183  * host1x_device_init() - initialize a host1x logical device
 184  * @device: host1x logical device
 185  *
 186  * The driver for the host1x logical device can call this during execution of
 187  * its &host1x_driver.probe implementation to initialize each of its clients.
 188  * The client drivers access the subsystem specific driver data using the
 189  * &host1x_client.parent field and driver data associated with it (usually by
 190  * calling dev_get_drvdata()).
 191  */
 192 int host1x_device_init(struct host1x_device *device)
 193 {
 194         struct host1x_client *client;
 195         int err;
 196
 197         mutex_lock(&device->clients_lock);
 198
 199         list_for_each_entry(client, &device->clients, list) {
 200                 if (client->ops && client->ops->early_init) {
 201                         err = client->ops->early_init(client);
 202                         if (err < 0) {
 203                                 dev_err(&device->dev, "failed to early initialize %s: %d\n",
 204                                         dev_name(client->dev), err);
 205                                 goto teardown_late;
 206                         }
 207                 }
 208         }
 209
 210         list_for_each_entry(client, &device->clients, list) {
 211                 if (client->ops && client->ops->init) {
 212                         err = client->ops->init(client);
 213                         if (err < 0) {
 214                                 dev_err(&device->dev,
 215                                         "failed to initialize %s: %d\n",
 216                                         dev_name(client->dev), err);
 217                                 goto teardown;
 218                         }
 219                 }
 220         }
 221
 222         mutex_unlock(&device->clients_lock);
 223
 224         return 0;
 225
 226 teardown:
 227         list_for_each_entry_continue_reverse(client, &device->clients, list)
 228                 if (client->ops->exit)
 229                         client->ops->exit(client);
 230
 231         /* reset client to end of list for late teardown */
 232         client = list_entry(&device->clients, struct host1x_client, list);
 233
 234 teardown_late:
 235         list_for_each_entry_continue_reverse(client, &device->clients, list)
 236                 if (client->ops->late_exit)
 237                         client->ops->late_exit(client);
 238
 239         mutex_unlock(&device->clients_lock);
 240         return err;
 241 }
 242 EXPORT_SYMBOL(host1x_device_init);
 243
 244 /**
 245  * host1x_device_exit() - uninitialize host1x logical device
 246  * @device: host1x logical device
 247  *
 248  * When the driver for a host1x logical device is unloaded, it can call this
 249  * function to tear down each of its clients. Typically this is done after a
 250  * subsystem-specific data structure is removed and the functionality can no
 251  * longer be used.
 252  */
 253 int host1x_device_exit(struct host1x_device *device)
 254 {
 255         struct host1x_client *client;
 256         int err;
 257
 258         mutex_lock(&device->clients_lock);
 259
 260         list_for_each_entry_reverse(client, &device->clients, list) {
 261                 if (client->ops && client->ops->exit) {
 262                         err = client->ops->exit(client);
 263                         if (err < 0) {
 264                                 dev_err(&device->dev,
 265                                         "failed to cleanup %s: %d\n",
 266                                         dev_name(client->dev), err);
 267                                 mutex_unlock(&device->clients_lock);
 268                                 return err;
 269                         }
 270                 }
 271         }
 272
 273         list_for_each_entry_reverse(client, &device->clients, list) {
 274                 if (client->ops && client->ops->late_exit) {
 275                         err = client->ops->late_exit(client);
 276                         if (err < 0) {
 277                                 dev_err(&device->dev, "failed to late cleanup %s: %d\n",
 278                                         dev_name(client->dev), err);
 279                                 mutex_unlock(&device->clients_lock);
 280                                 return err;
 281                         }
 282                 }
 283         }
 284
 285         mutex_unlock(&device->clients_lock);
 286
 287         return 0;
 288 }
 289 EXPORT_SYMBOL(host1x_device_exit);
 290
 291 static int host1x_add_client(struct host1x *host1x,
 292                              struct host1x_client *client)
 293 {
 294         struct host1x_device *device;
 295         struct host1x_subdev *subdev;
 296
 297         mutex_lock(&host1x->devices_lock);
 298
 299         list_for_each_entry(device, &host1x->devices, list) {
 300                 list_for_each_entry(subdev, &device->subdevs, list) {
 301                         if (subdev->np == client->dev->of_node) {
 302                                 host1x_subdev_register(device, subdev, client);
 303                                 mutex_unlock(&host1x->devices_lock);
 304                                 return 0;
 305                         }
 306                 }
 307         }
 308
 309         mutex_unlock(&host1x->devices_lock);
 310         return -ENODEV;
 311 }
 312
 313 static int host1x_del_client(struct host1x *host1x,
 314                              struct host1x_client *client)
 315 {
 316         struct host1x_device *device, *dt;
 317         struct host1x_subdev *subdev;
 318
 319         mutex_lock(&host1x->devices_lock);
 320
 321         list_for_each_entry_safe(device, dt, &host1x->devices, list) {
 322                 list_for_each_entry(subdev, &device->active, list) {
 323                         if (subdev->client == client) {
 324                                 host1x_subdev_unregister(device, subdev);
 325                                 mutex_unlock(&host1x->devices_lock);
 326                                 return 0;
 327                         }
 328                 }
 329         }
 330
 331         mutex_unlock(&host1x->devices_lock);
 332         return -ENODEV;
 333 }
 334
 335 static int host1x_device_match(struct device *dev, struct device_driver *drv)
 336 {
 337         return strcmp(dev_name(dev), drv->name) == 0;
 338 }
 339
 340 static int host1x_device_uevent(struct device *dev,
 341                                 struct kobj_uevent_env *env)
 342 {
 343         struct device_node *np = dev->parent->of_node;
 344         unsigned int count = 0;
 345         struct property *p;
 346         const char *compat;
 347
 348         /*
 349          * This duplicates most of of_device_uevent(), but the latter cannot
 350          * be called from modules and operates on dev->of_node, which is not
 351          * available in this case.
 352          *
 353          * Note that this is really only needed for backwards compatibility
 354          * with libdrm, which parses this information from sysfs and will
 355          * fail if it can't find the OF_FULLNAME, specifically.
 356          */
 357         add_uevent_var(env, "OF_NAME=%pOFn", np);
 358         add_uevent_var(env, "OF_FULLNAME=%pOF", np);
 359
 360         of_property_for_each_string(np, "compatible", p, compat) {
 361                 add_uevent_var(env, "OF_COMPATIBLE_%u=%s", count, compat);
 362                 count++;
 363         }
 364
 365         add_uevent_var(env, "OF_COMPATIBLE_N=%u", count);
 366
 367         return 0;
 368 }
 369
 370 static int host1x_dma_configure(struct device *dev)
 371 {
 372         return of_dma_configure(dev, dev->of_node, true);
 373 }
 374
 375 static const struct dev_pm_ops host1x_device_pm_ops = {
 376         .suspend = pm_generic_suspend,
 377         .resume = pm_generic_resume,
 378         .freeze = pm_generic_freeze,
 379         .thaw = pm_generic_thaw,
 380         .poweroff = pm_generic_poweroff,
 381         .restore = pm_generic_restore,
 382 };
 383
 384 struct bus_type host1x_bus_type = {
 385         .name = "host1x",
 386         .match = host1x_device_match,
 387         .uevent = host1x_device_uevent,
 388         .dma_configure = host1x_dma_configure,
 389         .pm = &host1x_device_pm_ops,
 390 };
 391
 392 static void __host1x_device_del(struct host1x_device *device)
 393 {
 394         struct host1x_subdev *subdev, *sd;
 395         struct host1x_client *client, *cl;
 396
 397         mutex_lock(&device->subdevs_lock);
 398
 399         /* unregister subdevices */
 400         list_for_each_entry_safe(subdev, sd, &device->active, list) {
 401                 /*
 402                  * host1x_subdev_unregister() will remove the client from
 403                  * any lists, so we'll need to manually add it back to the
 404                  * list of idle clients.
 405                  *
 406                  * XXX: Alternatively, perhaps don't remove the client from
 407                  * any lists in host1x_subdev_unregister() and instead do
 408                  * that explicitly from host1x_unregister_client()?
 409                  */
 410                 client = subdev->client;
 411
 412                 __host1x_subdev_unregister(device, subdev);
 413
 414                 /* add the client to the list of idle clients */
 415                 mutex_lock(&clients_lock);
 416                 list_add_tail(&client->list, &clients);
 417                 mutex_unlock(&clients_lock);
 418         }
 419
 420         /* remove subdevices */
 421         list_for_each_entry_safe(subdev, sd, &device->subdevs, list)
 422                 host1x_subdev_del(subdev);
 423
 424         mutex_unlock(&device->subdevs_lock);
 425
 426         /* move clients to idle list */
 427         mutex_lock(&clients_lock);
 428         mutex_lock(&device->clients_lock);
 429
 430         list_for_each_entry_safe(client, cl, &device->clients, list)
 431                 list_move_tail(&client->list, &clients);
 432
 433         mutex_unlock(&device->clients_lock);
 434         mutex_unlock(&clients_lock);
 435
 436         /* finally remove the device */
 437         list_del_init(&device->list);
 438 }
 439
 440 static void host1x_device_release(struct device *dev)
 441 {
 442         struct host1x_device *device = to_host1x_device(dev);
 443
 444         __host1x_device_del(device);
 445         kfree(device);
 446 }
 447
 448 static int host1x_device_add(struct host1x *host1x,
 449                              struct host1x_driver *driver)
 450 {
 451         struct host1x_client *client, *tmp;
 452         struct host1x_subdev *subdev;
 453         struct host1x_device *device;
 454         int err;
 455
 456         device = kzalloc(sizeof(*device), GFP_KERNEL);
 457         if (!device)
 458                 return -ENOMEM;
 459
 460         device_initialize(&device->dev);
 461
 462         mutex_init(&device->subdevs_lock);
 463         INIT_LIST_HEAD(&device->subdevs);
 464         INIT_LIST_HEAD(&device->active);
 465         mutex_init(&device->clients_lock);
 466         INIT_LIST_HEAD(&device->clients);
 467         INIT_LIST_HEAD(&device->list);
 468         device->driver = driver;
 469
 470         device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask;
 471         device->dev.dma_mask = &device->dev.coherent_dma_mask;
 472         dev_set_name(&device->dev, "%s", driver->driver.name);
 473         device->dev.release = host1x_device_release;
 474         device->dev.bus = &host1x_bus_type;
 475         device->dev.parent = host1x->dev;
 476
 477         of_dma_configure(&device->dev, host1x->dev->of_node, true);
 478
 479         device->dev.dma_parms = &device->dma_parms;
 480         dma_set_max_seg_size(&device->dev, UINT_MAX);
 481
 482         err = host1x_device_parse_dt(device, driver);
 483         if (err < 0) {
 484                 kfree(device);
 485                 return err;
 486         }
 487
 488         list_add_tail(&device->list, &host1x->devices);
 489
 490         mutex_lock(&clients_lock);
 491
 492         list_for_each_entry_safe(client, tmp, &clients, list) {
 493                 list_for_each_entry(subdev, &device->subdevs, list) {
 494                         if (subdev->np == client->dev->of_node) {
 495                                 host1x_subdev_register(device, subdev, client);
 496                                 break;
 497                         }
 498                 }
 499         }
 500
 501         mutex_unlock(&clients_lock);
 502
 503         return 0;
 504 }
 505
 506 /*
 507  * Removes a device by first unregistering any subdevices and then removing
 508  * itself from the list of devices.
 509  *
 510  * This function must be called with the host1x->devices_lock held.
 511  */
 512 static void host1x_device_del(struct host1x *host1x,
 513                               struct host1x_device *device)
 514 {
 515         if (device->registered) {
 516                 device->registered = false;
 517                 device_del(&device->dev);
 518         }
 519
 520         put_device(&device->dev);
 521 }
 522
 523 static void host1x_attach_driver(struct host1x *host1x,
 524                                  struct host1x_driver *driver)
 525 {
 526         struct host1x_device *device;
 527         int err;
 528
 529         mutex_lock(&host1x->devices_lock);
 530
 531         list_for_each_entry(device, &host1x->devices, list) {
 532                 if (device->driver == driver) {
 533                         mutex_unlock(&host1x->devices_lock);
 534                         return;
 535                 }
 536         }
 537
 538         err = host1x_device_add(host1x, driver);
 539         if (err < 0)
 540                 dev_err(host1x->dev, "failed to allocate device: %d\n", err);
 541
 542         mutex_unlock(&host1x->devices_lock);
 543 }
 544
 545 static void host1x_detach_driver(struct host1x *host1x,
 546                                  struct host1x_driver *driver)
 547 {
 548         struct host1x_device *device, *tmp;
 549
 550         mutex_lock(&host1x->devices_lock);
 551
 552         list_for_each_entry_safe(device, tmp, &host1x->devices, list)
 553                 if (device->driver == driver)
 554                         host1x_device_del(host1x, device);
 555
 556         mutex_unlock(&host1x->devices_lock);
 557 }
 558
 559 static int host1x_devices_show(struct seq_file *s, void *data)
 560 {
 561         struct host1x *host1x = s->private;
 562         struct host1x_device *device;
 563
 564         mutex_lock(&host1x->devices_lock);
 565
 566         list_for_each_entry(device, &host1x->devices, list) {
 567                 struct host1x_subdev *subdev;
 568
 569                 seq_printf(s, "%s\n", dev_name(&device->dev));
 570
 571                 mutex_lock(&device->subdevs_lock);
 572
 573                 list_for_each_entry(subdev, &device->active, list)
 574                         seq_printf(s, "  %pOFf: %s\n", subdev->np,
 575                                    dev_name(subdev->client->dev));
 576
 577                 list_for_each_entry(subdev, &device->subdevs, list)
 578                         seq_printf(s, "  %pOFf:\n", subdev->np);
 579
 580                 mutex_unlock(&device->subdevs_lock);
 581         }
 582
 583         mutex_unlock(&host1x->devices_lock);
 584
 585         return 0;
 586 }
 587 DEFINE_SHOW_ATTRIBUTE(host1x_devices);
 588
 589 /**
 590  * host1x_register() - register a host1x controller
 591  * @host1x: host1x controller
 592  *
 593  * The host1x controller driver uses this to register a host1x controller with
 594  * the infrastructure. Note that all Tegra SoC generations have only ever come
 595  * with a single host1x instance, so this function is somewhat academic.
 596  */
 597 int host1x_register(struct host1x *host1x)
 598 {
 599         struct host1x_driver *driver;
 600
 601         mutex_lock(&devices_lock);
 602         list_add_tail(&host1x->list, &devices);
 603         mutex_unlock(&devices_lock);
 604
 605         mutex_lock(&drivers_lock);
 606
 607         list_for_each_entry(driver, &drivers, list)
 608                 host1x_attach_driver(host1x, driver);
 609
 610         mutex_unlock(&drivers_lock);
 611
 612         debugfs_create_file("devices", S_IRUGO, host1x->debugfs, host1x,
 613                             &host1x_devices_fops);
 614
 615         return 0;
 616 }
 617
 618 /**
 619  * host1x_unregister() - unregister a host1x controller
 620  * @host1x: host1x controller
 621  *
 622  * The host1x controller driver uses this to remove a host1x controller from
 623  * the infrastructure.
 624  */
 625 int host1x_unregister(struct host1x *host1x)
 626 {
 627         struct host1x_driver *driver;
 628
 629         mutex_lock(&drivers_lock);
 630
 631         list_for_each_entry(driver, &drivers, list)
 632                 host1x_detach_driver(host1x, driver);
 633
 634         mutex_unlock(&drivers_lock);
 635
 636         mutex_lock(&devices_lock);
 637         list_del_init(&host1x->list);
 638         mutex_unlock(&devices_lock);
 639
 640         return 0;
 641 }
 642
 643 static int host1x_device_probe(struct device *dev)
 644 {
 645         struct host1x_driver *driver = to_host1x_driver(dev->driver);
 646         struct host1x_device *device = to_host1x_device(dev);
 647
 648         if (driver->probe)
 649                 return driver->probe(device);
 650
 651         return 0;
 652 }
 653
 654 static int host1x_device_remove(struct device *dev)
 655 {
 656         struct host1x_driver *driver = to_host1x_driver(dev->driver);
 657         struct host1x_device *device = to_host1x_device(dev);
 658
 659         if (driver->remove)
 660                 return driver->remove(device);
 661
 662         return 0;
 663 }
 664
 665 static void host1x_device_shutdown(struct device *dev)
 666 {
 667         struct host1x_driver *driver = to_host1x_driver(dev->driver);
 668         struct host1x_device *device = to_host1x_device(dev);
 669
 670         if (driver->shutdown)
 671                 driver->shutdown(device);
 672 }
 673
 674 /**
 675  * host1x_driver_register_full() - register a host1x driver
 676  * @driver: host1x driver
 677  * @owner: owner module
 678  *
 679  * Drivers for host1x logical devices call this function to register a driver
 680  * with the infrastructure. Note that since these drive logical devices, the
 681  * registration of the driver actually triggers tho logical device creation.
 682  * A logical device will be created for each host1x instance.
 683  */
 684 int host1x_driver_register_full(struct host1x_driver *driver,
 685                                 struct module *owner)
 686 {
 687         struct host1x *host1x;
 688
 689         INIT_LIST_HEAD(&driver->list);
 690
 691         mutex_lock(&drivers_lock);
 692         list_add_tail(&driver->list, &drivers);
 693         mutex_unlock(&drivers_lock);
 694
 695         mutex_lock(&devices_lock);
 696
 697         list_for_each_entry(host1x, &devices, list)
 698                 host1x_attach_driver(host1x, driver);
 699
 700         mutex_unlock(&devices_lock);
 701
 702         driver->driver.bus = &host1x_bus_type;
 703         driver->driver.owner = owner;
 704         driver->driver.probe = host1x_device_probe;
 705         driver->driver.remove = host1x_device_remove;
 706         driver->driver.shutdown = host1x_device_shutdown;
 707
 708         return driver_register(&driver->driver);
 709 }
 710 EXPORT_SYMBOL(host1x_driver_register_full);
 711
 712 /**
 713  * host1x_driver_unregister() - unregister a host1x driver
 714  * @driver: host1x driver
 715  *
 716  * Unbinds the driver from each of the host1x logical devices that it is
 717  * bound to, effectively removing the subsystem devices that they represent.
 718  */
 719 void host1x_driver_unregister(struct host1x_driver *driver)
 720 {
 721         struct host1x *host1x;
 722
 723         driver_unregister(&driver->driver);
 724
 725         mutex_lock(&devices_lock);
 726
 727         list_for_each_entry(host1x, &devices, list)
 728                 host1x_detach_driver(host1x, driver);
 729
 730         mutex_unlock(&devices_lock);
 731
 732         mutex_lock(&drivers_lock);
 733         list_del_init(&driver->list);
 734         mutex_unlock(&drivers_lock);
 735 }
 736 EXPORT_SYMBOL(host1x_driver_unregister);
 737
 738 /**
 739  * __host1x_client_init() - initialize a host1x client
 740  * @client: host1x client
 741  * @key: lock class key for the client-specific mutex
 742  */
 743 void __host1x_client_init(struct host1x_client *client, struct lock_class_key *key)
 744 {
 745         INIT_LIST_HEAD(&client->list);
 746         __mutex_init(&client->lock, "host1x client lock", key);
 747         client->usecount = 0;
 748 }
 749 EXPORT_SYMBOL(__host1x_client_init);
 750
 751 /**
 752  * host1x_client_exit() - uninitialize a host1x client
 753  * @client: host1x client
 754  */
 755 void host1x_client_exit(struct host1x_client *client)
 756 {
 757         mutex_destroy(&client->lock);
 758 }
 759 EXPORT_SYMBOL(host1x_client_exit);
 760
 761 /**
 762  * __host1x_client_register() - register a host1x client
 763  * @client: host1x client
 764  * @key: lock class key for the client-specific mutex
 765  *
 766  * Registers a host1x client with each host1x controller instance. Note that
 767  * each client will only match their parent host1x controller and will only be
 768  * associated with that instance. Once all clients have been registered with
 769  * their parent host1x controller, the infrastructure will set up the logical
 770  * device and call host1x_device_init(), which will in turn call each client's
 771  * &host1x_client_ops.init implementation.
 772  */
 773 int __host1x_client_register(struct host1x_client *client)
 774 {
 775         struct host1x *host1x;
 776         int err;
 777
 778         mutex_lock(&devices_lock);
 779
 780         list_for_each_entry(host1x, &devices, list) {
 781                 err = host1x_add_client(host1x, client);
 782                 if (!err) {
 783                         mutex_unlock(&devices_lock);
 784                         return 0;
 785                 }
 786         }
 787
 788         mutex_unlock(&devices_lock);
 789
 790         mutex_lock(&clients_lock);
 791         list_add_tail(&client->list, &clients);
 792         mutex_unlock(&clients_lock);
 793
 794         return 0;
 795 }
 796 EXPORT_SYMBOL(__host1x_client_register);
 797
 798 /**
 799  * host1x_client_unregister() - unregister a host1x client
 800  * @client: host1x client
 801  *
 802  * Removes a host1x client from its host1x controller instance. If a logical
 803  * device has already been initialized, it will be torn down.
 804  */
 805 int host1x_client_unregister(struct host1x_client *client)
 806 {
 807         struct host1x_client *c;
 808         struct host1x *host1x;
 809         int err;
 810
 811         mutex_lock(&devices_lock);
 812
 813         list_for_each_entry(host1x, &devices, list) {
 814                 err = host1x_del_client(host1x, client);
 815                 if (!err) {
 816                         mutex_unlock(&devices_lock);
 817                         return 0;
 818                 }
 819         }
 820
 821         mutex_unlock(&devices_lock);
 822         mutex_lock(&clients_lock);
 823
 824         list_for_each_entry(c, &clients, list) {
 825                 if (c == client) {
 826                         list_del_init(&c->list);
 827                         break;
 828                 }
 829         }
 830
 831         mutex_unlock(&clients_lock);
 832
 833         return 0;
 834 }
 835 EXPORT_SYMBOL(host1x_client_unregister);
 836
 837 int host1x_client_suspend(struct host1x_client *client)
 838 {
 839         int err = 0;
 840
 841         mutex_lock(&client->lock);
 842
 843         if (client->usecount == 1) {
 844                 if (client->ops && client->ops->suspend) {
 845                         err = client->ops->suspend(client);
 846                         if (err < 0)
 847                                 goto unlock;
 848                 }
 849         }
 850
 851         client->usecount--;
 852         dev_dbg(client->dev, "use count: %u\n", client->usecount);
 853
 854         if (client->parent) {
 855                 err = host1x_client_suspend(client->parent);
 856                 if (err < 0)
 857                         goto resume;
 858         }
 859
 860         goto unlock;
 861
 862 resume:
 863         if (client->usecount == 0)
 864                 if (client->ops && client->ops->resume)
 865                         client->ops->resume(client);
 866
 867         client->usecount++;
 868 unlock:
 869         mutex_unlock(&client->lock);
 870         return err;
 871 }
 872 EXPORT_SYMBOL(host1x_client_suspend);
 873
 874 int host1x_client_resume(struct host1x_client *client)
 875 {
 876         int err = 0;
 877
 878         mutex_lock(&client->lock);
 879
 880         if (client->parent) {
 881                 err = host1x_client_resume(client->parent);
 882                 if (err < 0)
 883                         goto unlock;
 884         }
 885
 886         if (client->usecount == 0) {
 887                 if (client->ops && client->ops->resume) {
 888                         err = client->ops->resume(client);
 889                         if (err < 0)
 890                                 goto suspend;
 891                 }
 892         }
 893
 894         client->usecount++;
 895         dev_dbg(client->dev, "use count: %u\n", client->usecount);
 896
 897         goto unlock;
 898
 899 suspend:
 900         if (client->parent)
 901                 host1x_client_suspend(client->parent);
 902 unlock:
 903         mutex_unlock(&client->lock);
 904         return err;
 905 }
 906 EXPORT_SYMBOL(host1x_client_resume);