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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2012 Avionic Design GmbH4 * Copyright (C) 2012-2013, NVIDIA Corporation5 */6 7#include <linux/debugfs.h>8#include <linux/dma-mapping.h>9#include <linux/host1x.h>10#include <linux/of.h>11#include <linux/seq_file.h>12#include <linux/slab.h>13#include <linux/of_device.h>14 15#include "bus.h"16#include "dev.h"17 18static DEFINE_MUTEX(clients_lock);19static LIST_HEAD(clients);20 21static DEFINE_MUTEX(drivers_lock);22static LIST_HEAD(drivers);23 24static DEFINE_MUTEX(devices_lock);25static LIST_HEAD(devices);26 27struct host1x_subdev {28 struct host1x_client *client;29 struct device_node *np;30 struct list_head list;31};32 33/**34 * host1x_subdev_add() - add a new subdevice with an associated device node35 * @device: host1x device to add the subdevice to36 * @driver: host1x driver containing the subdevices37 * @np: device node38 */39static int host1x_subdev_add(struct host1x_device *device,40 struct host1x_driver *driver,41 struct device_node *np)42{43 struct host1x_subdev *subdev;44 struct device_node *child;45 int err;46 47 subdev = kzalloc(sizeof(*subdev), GFP_KERNEL);48 if (!subdev)49 return -ENOMEM;50 51 INIT_LIST_HEAD(&subdev->list);52 subdev->np = of_node_get(np);53 54 mutex_lock(&device->subdevs_lock);55 list_add_tail(&subdev->list, &device->subdevs);56 mutex_unlock(&device->subdevs_lock);57 58 /* recursively add children */59 for_each_child_of_node(np, child) {60 if (of_match_node(driver->subdevs, child) &&61 of_device_is_available(child)) {62 err = host1x_subdev_add(device, driver, child);63 if (err < 0) {64 /* XXX cleanup? */65 of_node_put(child);66 return err;67 }68 }69 }70 71 return 0;72}73 74/**75 * host1x_subdev_del() - remove subdevice76 * @subdev: subdevice to remove77 */78static void host1x_subdev_del(struct host1x_subdev *subdev)79{80 list_del(&subdev->list);81 of_node_put(subdev->np);82 kfree(subdev);83}84 85/**86 * host1x_device_parse_dt() - scan device tree and add matching subdevices87 * @device: host1x logical device88 * @driver: host1x driver89 */90static int host1x_device_parse_dt(struct host1x_device *device,91 struct host1x_driver *driver)92{93 struct device_node *np;94 int err;95 96 for_each_child_of_node(device->dev.parent->of_node, np) {97 if (of_match_node(driver->subdevs, np) &&98 of_device_is_available(np)) {99 err = host1x_subdev_add(device, driver, np);100 if (err < 0) {101 of_node_put(np);102 return err;103 }104 }105 }106 107 return 0;108}109 110static void host1x_subdev_register(struct host1x_device *device,111 struct host1x_subdev *subdev,112 struct host1x_client *client)113{114 int err;115 116 /*117 * Move the subdevice to the list of active (registered) subdevices118 * and associate it with a client. At the same time, associate the119 * client with its parent device.120 */121 mutex_lock(&device->subdevs_lock);122 mutex_lock(&device->clients_lock);123 list_move_tail(&client->list, &device->clients);124 list_move_tail(&subdev->list, &device->active);125 client->host = &device->dev;126 subdev->client = client;127 mutex_unlock(&device->clients_lock);128 mutex_unlock(&device->subdevs_lock);129 130 if (list_empty(&device->subdevs)) {131 err = device_add(&device->dev);132 if (err < 0)133 dev_err(&device->dev, "failed to add: %d\n", err);134 else135 device->registered = true;136 }137}138 139static void __host1x_subdev_unregister(struct host1x_device *device,140 struct host1x_subdev *subdev)141{142 struct host1x_client *client = subdev->client;143 144 /*145 * If all subdevices have been activated, we're about to remove the146 * first active subdevice, so unload the driver first.147 */148 if (list_empty(&device->subdevs)) {149 if (device->registered) {150 device->registered = false;151 device_del(&device->dev);152 }153 }154 155 /*156 * Move the subdevice back to the list of idle subdevices and remove157 * it from list of clients.158 */159 mutex_lock(&device->clients_lock);160 subdev->client = NULL;161 client->host = NULL;162 list_move_tail(&subdev->list, &device->subdevs);163 /*164 * XXX: Perhaps don't do this here, but rather explicitly remove it165 * when the device is about to be deleted.166 *167 * This is somewhat complicated by the fact that this function is168 * used to remove the subdevice when a client is unregistered but169 * also when the composite device is about to be removed.170 */171 list_del_init(&client->list);172 mutex_unlock(&device->clients_lock);173}174 175static void host1x_subdev_unregister(struct host1x_device *device,176 struct host1x_subdev *subdev)177{178 mutex_lock(&device->subdevs_lock);179 __host1x_subdev_unregister(device, subdev);180 mutex_unlock(&device->subdevs_lock);181}182 183/**184 * host1x_device_init() - initialize a host1x logical device185 * @device: host1x logical device186 *187 * The driver for the host1x logical device can call this during execution of188 * its &host1x_driver.probe implementation to initialize each of its clients.189 * The client drivers access the subsystem specific driver data using the190 * &host1x_client.parent field and driver data associated with it (usually by191 * calling dev_get_drvdata()).192 */193int host1x_device_init(struct host1x_device *device)194{195 struct host1x_client *client;196 int err;197 198 mutex_lock(&device->clients_lock);199 200 list_for_each_entry(client, &device->clients, list) {201 if (client->ops && client->ops->early_init) {202 err = client->ops->early_init(client);203 if (err < 0) {204 dev_err(&device->dev, "failed to early initialize %s: %d\n",205 dev_name(client->dev), err);206 goto teardown_late;207 }208 }209 }210 211 list_for_each_entry(client, &device->clients, list) {212 if (client->ops && client->ops->init) {213 err = client->ops->init(client);214 if (err < 0) {215 dev_err(&device->dev,216 "failed to initialize %s: %d\n",217 dev_name(client->dev), err);218 goto teardown;219 }220 }221 }222 223 mutex_unlock(&device->clients_lock);224 225 return 0;226 227teardown:228 list_for_each_entry_continue_reverse(client, &device->clients, list)229 if (client->ops->exit)230 client->ops->exit(client);231 232 /* reset client to end of list for late teardown */233 client = list_entry(&device->clients, struct host1x_client, list);234 235teardown_late:236 list_for_each_entry_continue_reverse(client, &device->clients, list)237 if (client->ops->late_exit)238 client->ops->late_exit(client);239 240 mutex_unlock(&device->clients_lock);241 return err;242}243EXPORT_SYMBOL(host1x_device_init);244 245/**246 * host1x_device_exit() - uninitialize host1x logical device247 * @device: host1x logical device248 *249 * When the driver for a host1x logical device is unloaded, it can call this250 * function to tear down each of its clients. Typically this is done after a251 * subsystem-specific data structure is removed and the functionality can no252 * longer be used.253 */254int host1x_device_exit(struct host1x_device *device)255{256 struct host1x_client *client;257 int err;258 259 mutex_lock(&device->clients_lock);260 261 list_for_each_entry_reverse(client, &device->clients, list) {262 if (client->ops && client->ops->exit) {263 err = client->ops->exit(client);264 if (err < 0) {265 dev_err(&device->dev,266 "failed to cleanup %s: %d\n",267 dev_name(client->dev), err);268 mutex_unlock(&device->clients_lock);269 return err;270 }271 }272 }273 274 list_for_each_entry_reverse(client, &device->clients, list) {275 if (client->ops && client->ops->late_exit) {276 err = client->ops->late_exit(client);277 if (err < 0) {278 dev_err(&device->dev, "failed to late cleanup %s: %d\n",279 dev_name(client->dev), err);280 mutex_unlock(&device->clients_lock);281 return err;282 }283 }284 }285 286 mutex_unlock(&device->clients_lock);287 288 return 0;289}290EXPORT_SYMBOL(host1x_device_exit);291 292static int host1x_add_client(struct host1x *host1x,293 struct host1x_client *client)294{295 struct host1x_device *device;296 struct host1x_subdev *subdev;297 298 mutex_lock(&host1x->devices_lock);299 300 list_for_each_entry(device, &host1x->devices, list) {301 list_for_each_entry(subdev, &device->subdevs, list) {302 if (subdev->np == client->dev->of_node) {303 host1x_subdev_register(device, subdev, client);304 mutex_unlock(&host1x->devices_lock);305 return 0;306 }307 }308 }309 310 mutex_unlock(&host1x->devices_lock);311 return -ENODEV;312}313 314static int host1x_del_client(struct host1x *host1x,315 struct host1x_client *client)316{317 struct host1x_device *device, *dt;318 struct host1x_subdev *subdev;319 320 mutex_lock(&host1x->devices_lock);321 322 list_for_each_entry_safe(device, dt, &host1x->devices, list) {323 list_for_each_entry(subdev, &device->active, list) {324 if (subdev->client == client) {325 host1x_subdev_unregister(device, subdev);326 mutex_unlock(&host1x->devices_lock);327 return 0;328 }329 }330 }331 332 mutex_unlock(&host1x->devices_lock);333 return -ENODEV;334}335 336static int host1x_device_match(struct device *dev, const struct device_driver *drv)337{338 return strcmp(dev_name(dev), drv->name) == 0;339}340 341/*342 * Note that this is really only needed for backwards compatibility343 * with libdrm, which parses this information from sysfs and will344 * fail if it can't find the OF_FULLNAME, specifically.345 */346static int host1x_device_uevent(const struct device *dev,347 struct kobj_uevent_env *env)348{349 of_device_uevent(dev->parent, env);350 351 return 0;352}353 354static const struct dev_pm_ops host1x_device_pm_ops = {355 .suspend = pm_generic_suspend,356 .resume = pm_generic_resume,357 .freeze = pm_generic_freeze,358 .thaw = pm_generic_thaw,359 .poweroff = pm_generic_poweroff,360 .restore = pm_generic_restore,361};362 363const struct bus_type host1x_bus_type = {364 .name = "host1x",365 .match = host1x_device_match,366 .uevent = host1x_device_uevent,367 .pm = &host1x_device_pm_ops,368};369 370static void __host1x_device_del(struct host1x_device *device)371{372 struct host1x_subdev *subdev, *sd;373 struct host1x_client *client, *cl;374 375 mutex_lock(&device->subdevs_lock);376 377 /* unregister subdevices */378 list_for_each_entry_safe(subdev, sd, &device->active, list) {379 /*380 * host1x_subdev_unregister() will remove the client from381 * any lists, so we'll need to manually add it back to the382 * list of idle clients.383 *384 * XXX: Alternatively, perhaps don't remove the client from385 * any lists in host1x_subdev_unregister() and instead do386 * that explicitly from host1x_unregister_client()?387 */388 client = subdev->client;389 390 __host1x_subdev_unregister(device, subdev);391 392 /* add the client to the list of idle clients */393 mutex_lock(&clients_lock);394 list_add_tail(&client->list, &clients);395 mutex_unlock(&clients_lock);396 }397 398 /* remove subdevices */399 list_for_each_entry_safe(subdev, sd, &device->subdevs, list)400 host1x_subdev_del(subdev);401 402 mutex_unlock(&device->subdevs_lock);403 404 /* move clients to idle list */405 mutex_lock(&clients_lock);406 mutex_lock(&device->clients_lock);407 408 list_for_each_entry_safe(client, cl, &device->clients, list)409 list_move_tail(&client->list, &clients);410 411 mutex_unlock(&device->clients_lock);412 mutex_unlock(&clients_lock);413 414 /* finally remove the device */415 list_del_init(&device->list);416}417 418static void host1x_device_release(struct device *dev)419{420 struct host1x_device *device = to_host1x_device(dev);421 422 __host1x_device_del(device);423 kfree(device);424}425 426static int host1x_device_add(struct host1x *host1x,427 struct host1x_driver *driver)428{429 struct host1x_client *client, *tmp;430 struct host1x_subdev *subdev;431 struct host1x_device *device;432 int err;433 434 device = kzalloc(sizeof(*device), GFP_KERNEL);435 if (!device)436 return -ENOMEM;437 438 device_initialize(&device->dev);439 440 mutex_init(&device->subdevs_lock);441 INIT_LIST_HEAD(&device->subdevs);442 INIT_LIST_HEAD(&device->active);443 mutex_init(&device->clients_lock);444 INIT_LIST_HEAD(&device->clients);445 INIT_LIST_HEAD(&device->list);446 device->driver = driver;447 448 device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask;449 device->dev.dma_mask = &device->dev.coherent_dma_mask;450 dev_set_name(&device->dev, "%s", driver->driver.name);451 device->dev.release = host1x_device_release;452 device->dev.bus = &host1x_bus_type;453 device->dev.parent = host1x->dev;454 455 device->dev.dma_parms = &device->dma_parms;456 dma_set_max_seg_size(&device->dev, UINT_MAX);457 458 err = host1x_device_parse_dt(device, driver);459 if (err < 0) {460 kfree(device);461 return err;462 }463 464 list_add_tail(&device->list, &host1x->devices);465 466 mutex_lock(&clients_lock);467 468 list_for_each_entry_safe(client, tmp, &clients, list) {469 list_for_each_entry(subdev, &device->subdevs, list) {470 if (subdev->np == client->dev->of_node) {471 host1x_subdev_register(device, subdev, client);472 break;473 }474 }475 }476 477 mutex_unlock(&clients_lock);478 479 return 0;480}481 482/*483 * Removes a device by first unregistering any subdevices and then removing484 * itself from the list of devices.485 *486 * This function must be called with the host1x->devices_lock held.487 */488static void host1x_device_del(struct host1x *host1x,489 struct host1x_device *device)490{491 if (device->registered) {492 device->registered = false;493 device_del(&device->dev);494 }495 496 put_device(&device->dev);497}498 499static void host1x_attach_driver(struct host1x *host1x,500 struct host1x_driver *driver)501{502 struct host1x_device *device;503 int err;504 505 mutex_lock(&host1x->devices_lock);506 507 list_for_each_entry(device, &host1x->devices, list) {508 if (device->driver == driver) {509 mutex_unlock(&host1x->devices_lock);510 return;511 }512 }513 514 err = host1x_device_add(host1x, driver);515 if (err < 0)516 dev_err(host1x->dev, "failed to allocate device: %d\n", err);517 518 mutex_unlock(&host1x->devices_lock);519}520 521static void host1x_detach_driver(struct host1x *host1x,522 struct host1x_driver *driver)523{524 struct host1x_device *device, *tmp;525 526 mutex_lock(&host1x->devices_lock);527 528 list_for_each_entry_safe(device, tmp, &host1x->devices, list)529 if (device->driver == driver)530 host1x_device_del(host1x, device);531 532 mutex_unlock(&host1x->devices_lock);533}534 535static int host1x_devices_show(struct seq_file *s, void *data)536{537 struct host1x *host1x = s->private;538 struct host1x_device *device;539 540 mutex_lock(&host1x->devices_lock);541 542 list_for_each_entry(device, &host1x->devices, list) {543 struct host1x_subdev *subdev;544 545 seq_printf(s, "%s\n", dev_name(&device->dev));546 547 mutex_lock(&device->subdevs_lock);548 549 list_for_each_entry(subdev, &device->active, list)550 seq_printf(s, " %pOFf: %s\n", subdev->np,551 dev_name(subdev->client->dev));552 553 list_for_each_entry(subdev, &device->subdevs, list)554 seq_printf(s, " %pOFf:\n", subdev->np);555 556 mutex_unlock(&device->subdevs_lock);557 }558 559 mutex_unlock(&host1x->devices_lock);560 561 return 0;562}563DEFINE_SHOW_ATTRIBUTE(host1x_devices);564 565/**566 * host1x_register() - register a host1x controller567 * @host1x: host1x controller568 *569 * The host1x controller driver uses this to register a host1x controller with570 * the infrastructure. Note that all Tegra SoC generations have only ever come571 * with a single host1x instance, so this function is somewhat academic.572 */573int host1x_register(struct host1x *host1x)574{575 struct host1x_driver *driver;576 577 mutex_lock(&devices_lock);578 list_add_tail(&host1x->list, &devices);579 mutex_unlock(&devices_lock);580 581 mutex_lock(&drivers_lock);582 583 list_for_each_entry(driver, &drivers, list)584 host1x_attach_driver(host1x, driver);585 586 mutex_unlock(&drivers_lock);587 588 debugfs_create_file("devices", S_IRUGO, host1x->debugfs, host1x,589 &host1x_devices_fops);590 591 return 0;592}593 594/**595 * host1x_unregister() - unregister a host1x controller596 * @host1x: host1x controller597 *598 * The host1x controller driver uses this to remove a host1x controller from599 * the infrastructure.600 */601int host1x_unregister(struct host1x *host1x)602{603 struct host1x_driver *driver;604 605 mutex_lock(&drivers_lock);606 607 list_for_each_entry(driver, &drivers, list)608 host1x_detach_driver(host1x, driver);609 610 mutex_unlock(&drivers_lock);611 612 mutex_lock(&devices_lock);613 list_del_init(&host1x->list);614 mutex_unlock(&devices_lock);615 616 return 0;617}618 619static int host1x_device_probe(struct device *dev)620{621 struct host1x_driver *driver = to_host1x_driver(dev->driver);622 struct host1x_device *device = to_host1x_device(dev);623 624 if (driver->probe)625 return driver->probe(device);626 627 return 0;628}629 630static int host1x_device_remove(struct device *dev)631{632 struct host1x_driver *driver = to_host1x_driver(dev->driver);633 struct host1x_device *device = to_host1x_device(dev);634 635 if (driver->remove)636 return driver->remove(device);637 638 return 0;639}640 641static void host1x_device_shutdown(struct device *dev)642{643 struct host1x_driver *driver = to_host1x_driver(dev->driver);644 struct host1x_device *device = to_host1x_device(dev);645 646 if (driver->shutdown)647 driver->shutdown(device);648}649 650/**651 * host1x_driver_register_full() - register a host1x driver652 * @driver: host1x driver653 * @owner: owner module654 *655 * Drivers for host1x logical devices call this function to register a driver656 * with the infrastructure. Note that since these drive logical devices, the657 * registration of the driver actually triggers tho logical device creation.658 * A logical device will be created for each host1x instance.659 */660int host1x_driver_register_full(struct host1x_driver *driver,661 struct module *owner)662{663 struct host1x *host1x;664 665 INIT_LIST_HEAD(&driver->list);666 667 mutex_lock(&drivers_lock);668 list_add_tail(&driver->list, &drivers);669 mutex_unlock(&drivers_lock);670 671 mutex_lock(&devices_lock);672 673 list_for_each_entry(host1x, &devices, list)674 host1x_attach_driver(host1x, driver);675 676 mutex_unlock(&devices_lock);677 678 driver->driver.bus = &host1x_bus_type;679 driver->driver.owner = owner;680 driver->driver.probe = host1x_device_probe;681 driver->driver.remove = host1x_device_remove;682 driver->driver.shutdown = host1x_device_shutdown;683 684 return driver_register(&driver->driver);685}686EXPORT_SYMBOL(host1x_driver_register_full);687 688/**689 * host1x_driver_unregister() - unregister a host1x driver690 * @driver: host1x driver691 *692 * Unbinds the driver from each of the host1x logical devices that it is693 * bound to, effectively removing the subsystem devices that they represent.694 */695void host1x_driver_unregister(struct host1x_driver *driver)696{697 struct host1x *host1x;698 699 driver_unregister(&driver->driver);700 701 mutex_lock(&devices_lock);702 703 list_for_each_entry(host1x, &devices, list)704 host1x_detach_driver(host1x, driver);705 706 mutex_unlock(&devices_lock);707 708 mutex_lock(&drivers_lock);709 list_del_init(&driver->list);710 mutex_unlock(&drivers_lock);711}712EXPORT_SYMBOL(host1x_driver_unregister);713 714/**715 * __host1x_client_init() - initialize a host1x client716 * @client: host1x client717 * @key: lock class key for the client-specific mutex718 */719void __host1x_client_init(struct host1x_client *client, struct lock_class_key *key)720{721 host1x_bo_cache_init(&client->cache);722 INIT_LIST_HEAD(&client->list);723 __mutex_init(&client->lock, "host1x client lock", key);724 client->usecount = 0;725}726EXPORT_SYMBOL(__host1x_client_init);727 728/**729 * host1x_client_exit() - uninitialize a host1x client730 * @client: host1x client731 */732void host1x_client_exit(struct host1x_client *client)733{734 mutex_destroy(&client->lock);735}736EXPORT_SYMBOL(host1x_client_exit);737 738/**739 * __host1x_client_register() - register a host1x client740 * @client: host1x client741 *742 * Registers a host1x client with each host1x controller instance. Note that743 * each client will only match their parent host1x controller and will only be744 * associated with that instance. Once all clients have been registered with745 * their parent host1x controller, the infrastructure will set up the logical746 * device and call host1x_device_init(), which will in turn call each client's747 * &host1x_client_ops.init implementation.748 */749int __host1x_client_register(struct host1x_client *client)750{751 struct host1x *host1x;752 int err;753 754 mutex_lock(&devices_lock);755 756 list_for_each_entry(host1x, &devices, list) {757 err = host1x_add_client(host1x, client);758 if (!err) {759 mutex_unlock(&devices_lock);760 return 0;761 }762 }763 764 mutex_unlock(&devices_lock);765 766 mutex_lock(&clients_lock);767 list_add_tail(&client->list, &clients);768 mutex_unlock(&clients_lock);769 770 return 0;771}772EXPORT_SYMBOL(__host1x_client_register);773 774/**775 * host1x_client_unregister() - unregister a host1x client776 * @client: host1x client777 *778 * Removes a host1x client from its host1x controller instance. If a logical779 * device has already been initialized, it will be torn down.780 */781void host1x_client_unregister(struct host1x_client *client)782{783 struct host1x_client *c;784 struct host1x *host1x;785 int err;786 787 mutex_lock(&devices_lock);788 789 list_for_each_entry(host1x, &devices, list) {790 err = host1x_del_client(host1x, client);791 if (!err) {792 mutex_unlock(&devices_lock);793 return;794 }795 }796 797 mutex_unlock(&devices_lock);798 mutex_lock(&clients_lock);799 800 list_for_each_entry(c, &clients, list) {801 if (c == client) {802 list_del_init(&c->list);803 break;804 }805 }806 807 mutex_unlock(&clients_lock);808 809 host1x_bo_cache_destroy(&client->cache);810}811EXPORT_SYMBOL(host1x_client_unregister);812 813int host1x_client_suspend(struct host1x_client *client)814{815 int err = 0;816 817 mutex_lock(&client->lock);818 819 if (client->usecount == 1) {820 if (client->ops && client->ops->suspend) {821 err = client->ops->suspend(client);822 if (err < 0)823 goto unlock;824 }825 }826 827 client->usecount--;828 dev_dbg(client->dev, "use count: %u\n", client->usecount);829 830 if (client->parent) {831 err = host1x_client_suspend(client->parent);832 if (err < 0)833 goto resume;834 }835 836 goto unlock;837 838resume:839 if (client->usecount == 0)840 if (client->ops && client->ops->resume)841 client->ops->resume(client);842 843 client->usecount++;844unlock:845 mutex_unlock(&client->lock);846 return err;847}848EXPORT_SYMBOL(host1x_client_suspend);849 850int host1x_client_resume(struct host1x_client *client)851{852 int err = 0;853 854 mutex_lock(&client->lock);855 856 if (client->parent) {857 err = host1x_client_resume(client->parent);858 if (err < 0)859 goto unlock;860 }861 862 if (client->usecount == 0) {863 if (client->ops && client->ops->resume) {864 err = client->ops->resume(client);865 if (err < 0)866 goto suspend;867 }868 }869 870 client->usecount++;871 dev_dbg(client->dev, "use count: %u\n", client->usecount);872 873 goto unlock;874 875suspend:876 if (client->parent)877 host1x_client_suspend(client->parent);878unlock:879 mutex_unlock(&client->lock);880 return err;881}882EXPORT_SYMBOL(host1x_client_resume);883 884struct host1x_bo_mapping *host1x_bo_pin(struct device *dev, struct host1x_bo *bo,885 enum dma_data_direction dir,886 struct host1x_bo_cache *cache)887{888 struct host1x_bo_mapping *mapping;889 890 if (cache) {891 mutex_lock(&cache->lock);892 893 list_for_each_entry(mapping, &cache->mappings, entry) {894 if (mapping->bo == bo && mapping->direction == dir) {895 kref_get(&mapping->ref);896 goto unlock;897 }898 }899 }900 901 mapping = bo->ops->pin(dev, bo, dir);902 if (IS_ERR(mapping))903 goto unlock;904 905 spin_lock(&mapping->bo->lock);906 list_add_tail(&mapping->list, &bo->mappings);907 spin_unlock(&mapping->bo->lock);908 909 if (cache) {910 INIT_LIST_HEAD(&mapping->entry);911 mapping->cache = cache;912 913 list_add_tail(&mapping->entry, &cache->mappings);914 915 /* bump reference count to track the copy in the cache */916 kref_get(&mapping->ref);917 }918 919unlock:920 if (cache)921 mutex_unlock(&cache->lock);922 923 return mapping;924}925EXPORT_SYMBOL(host1x_bo_pin);926 927static void __host1x_bo_unpin(struct kref *ref)928{929 struct host1x_bo_mapping *mapping = to_host1x_bo_mapping(ref);930 931 /*932 * When the last reference of the mapping goes away, make sure to remove the mapping from933 * the cache.934 */935 if (mapping->cache)936 list_del(&mapping->entry);937 938 spin_lock(&mapping->bo->lock);939 list_del(&mapping->list);940 spin_unlock(&mapping->bo->lock);941 942 mapping->bo->ops->unpin(mapping);943}944 945void host1x_bo_unpin(struct host1x_bo_mapping *mapping)946{947 struct host1x_bo_cache *cache = mapping->cache;948 949 if (cache)950 mutex_lock(&cache->lock);951 952 kref_put(&mapping->ref, __host1x_bo_unpin);953 954 if (cache)955 mutex_unlock(&cache->lock);956}957EXPORT_SYMBOL(host1x_bo_unpin);958