2 * Copyright (C) 2012 Avionic Design GmbH
3 * Copyright (C) 2012-2013, NVIDIA Corporation
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.
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
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 #include <linux/host1x.h>
20 #include <linux/slab.h>
25 static DEFINE_MUTEX(clients_lock);
26 static LIST_HEAD(clients);
28 static DEFINE_MUTEX(drivers_lock);
29 static LIST_HEAD(drivers);
31 static DEFINE_MUTEX(devices_lock);
32 static LIST_HEAD(devices);
34 struct host1x_subdev {
35 struct host1x_client *client;
36 struct device_node *np;
37 struct list_head list;
41 * host1x_subdev_add() - add a new subdevice with an associated device node
43 static int host1x_subdev_add(struct host1x_device *device,
44 struct device_node *np)
46 struct host1x_subdev *subdev;
48 subdev = kzalloc(sizeof(*subdev), GFP_KERNEL);
52 INIT_LIST_HEAD(&subdev->list);
53 subdev->np = of_node_get(np);
55 mutex_lock(&device->subdevs_lock);
56 list_add_tail(&subdev->list, &device->subdevs);
57 mutex_unlock(&device->subdevs_lock);
63 * host1x_subdev_del() - remove subdevice
65 static void host1x_subdev_del(struct host1x_subdev *subdev)
67 list_del(&subdev->list);
68 of_node_put(subdev->np);
73 * host1x_device_parse_dt() - scan device tree and add matching subdevices
75 static int host1x_device_parse_dt(struct host1x_device *device)
77 struct device_node *np;
80 for_each_child_of_node(device->dev.parent->of_node, np) {
81 if (of_match_node(device->driver->subdevs, np) &&
82 of_device_is_available(np)) {
83 err = host1x_subdev_add(device, np);
92 static void host1x_subdev_register(struct host1x_device *device,
93 struct host1x_subdev *subdev,
94 struct host1x_client *client)
99 * Move the subdevice to the list of active (registered) subdevices
100 * and associate it with a client. At the same time, associate the
101 * client with its parent device.
103 mutex_lock(&device->subdevs_lock);
104 mutex_lock(&device->clients_lock);
105 list_move_tail(&client->list, &device->clients);
106 list_move_tail(&subdev->list, &device->active);
107 client->parent = &device->dev;
108 subdev->client = client;
109 mutex_unlock(&device->clients_lock);
110 mutex_unlock(&device->subdevs_lock);
113 * When all subdevices have been registered, the composite device is
114 * ready to be probed.
116 if (list_empty(&device->subdevs)) {
117 err = device->driver->probe(device);
119 dev_err(&device->dev, "probe failed: %d\n", err);
123 static void __host1x_subdev_unregister(struct host1x_device *device,
124 struct host1x_subdev *subdev)
126 struct host1x_client *client = subdev->client;
130 * If all subdevices have been activated, we're about to remove the
131 * first active subdevice, so unload the driver first.
133 if (list_empty(&device->subdevs)) {
134 err = device->driver->remove(device);
136 dev_err(&device->dev, "remove failed: %d\n", err);
140 * Move the subdevice back to the list of idle subdevices and remove
141 * it from list of clients.
143 mutex_lock(&device->clients_lock);
144 subdev->client = NULL;
145 client->parent = NULL;
146 list_move_tail(&subdev->list, &device->subdevs);
148 * XXX: Perhaps don't do this here, but rather explicitly remove it
149 * when the device is about to be deleted.
151 * This is somewhat complicated by the fact that this function is
152 * used to remove the subdevice when a client is unregistered but
153 * also when the composite device is about to be removed.
155 list_del_init(&client->list);
156 mutex_unlock(&device->clients_lock);
159 static void host1x_subdev_unregister(struct host1x_device *device,
160 struct host1x_subdev *subdev)
162 mutex_lock(&device->subdevs_lock);
163 __host1x_subdev_unregister(device, subdev);
164 mutex_unlock(&device->subdevs_lock);
167 int host1x_device_init(struct host1x_device *device)
169 struct host1x_client *client;
172 mutex_lock(&device->clients_lock);
174 list_for_each_entry(client, &device->clients, list) {
175 if (client->ops && client->ops->init) {
176 err = client->ops->init(client);
178 dev_err(&device->dev,
179 "failed to initialize %s: %d\n",
180 dev_name(client->dev), err);
181 mutex_unlock(&device->clients_lock);
187 mutex_unlock(&device->clients_lock);
192 int host1x_device_exit(struct host1x_device *device)
194 struct host1x_client *client;
197 mutex_lock(&device->clients_lock);
199 list_for_each_entry_reverse(client, &device->clients, list) {
200 if (client->ops && client->ops->exit) {
201 err = client->ops->exit(client);
203 dev_err(&device->dev,
204 "failed to cleanup %s: %d\n",
205 dev_name(client->dev), err);
206 mutex_unlock(&device->clients_lock);
212 mutex_unlock(&device->clients_lock);
217 static int host1x_register_client(struct host1x *host1x,
218 struct host1x_client *client)
220 struct host1x_device *device;
221 struct host1x_subdev *subdev;
223 mutex_lock(&host1x->devices_lock);
225 list_for_each_entry(device, &host1x->devices, list) {
226 list_for_each_entry(subdev, &device->subdevs, list) {
227 if (subdev->np == client->dev->of_node) {
228 host1x_subdev_register(device, subdev, client);
229 mutex_unlock(&host1x->devices_lock);
235 mutex_unlock(&host1x->devices_lock);
239 static int host1x_unregister_client(struct host1x *host1x,
240 struct host1x_client *client)
242 struct host1x_device *device, *dt;
243 struct host1x_subdev *subdev;
245 mutex_lock(&host1x->devices_lock);
247 list_for_each_entry_safe(device, dt, &host1x->devices, list) {
248 list_for_each_entry(subdev, &device->active, list) {
249 if (subdev->client == client) {
250 host1x_subdev_unregister(device, subdev);
251 mutex_unlock(&host1x->devices_lock);
257 mutex_unlock(&host1x->devices_lock);
261 static struct bus_type host1x_bus_type = {
265 int host1x_bus_init(void)
267 return bus_register(&host1x_bus_type);
270 void host1x_bus_exit(void)
272 bus_unregister(&host1x_bus_type);
275 static void host1x_device_release(struct device *dev)
277 struct host1x_device *device = to_host1x_device(dev);
282 static int host1x_device_add(struct host1x *host1x,
283 struct host1x_driver *driver)
285 struct host1x_client *client, *tmp;
286 struct host1x_subdev *subdev;
287 struct host1x_device *device;
290 device = kzalloc(sizeof(*device), GFP_KERNEL);
294 mutex_init(&device->subdevs_lock);
295 INIT_LIST_HEAD(&device->subdevs);
296 INIT_LIST_HEAD(&device->active);
297 mutex_init(&device->clients_lock);
298 INIT_LIST_HEAD(&device->clients);
299 INIT_LIST_HEAD(&device->list);
300 device->driver = driver;
302 device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask;
303 device->dev.dma_mask = &device->dev.coherent_dma_mask;
304 device->dev.release = host1x_device_release;
305 dev_set_name(&device->dev, "%s", driver->name);
306 device->dev.bus = &host1x_bus_type;
307 device->dev.parent = host1x->dev;
309 err = device_register(&device->dev);
313 err = host1x_device_parse_dt(device);
315 device_unregister(&device->dev);
319 mutex_lock(&host1x->devices_lock);
320 list_add_tail(&device->list, &host1x->devices);
321 mutex_unlock(&host1x->devices_lock);
323 mutex_lock(&clients_lock);
325 list_for_each_entry_safe(client, tmp, &clients, list) {
326 list_for_each_entry(subdev, &device->subdevs, list) {
327 if (subdev->np == client->dev->of_node) {
328 host1x_subdev_register(device, subdev, client);
334 mutex_unlock(&clients_lock);
340 * Removes a device by first unregistering any subdevices and then removing
341 * itself from the list of devices.
343 * This function must be called with the host1x->devices_lock held.
345 static void host1x_device_del(struct host1x *host1x,
346 struct host1x_device *device)
348 struct host1x_subdev *subdev, *sd;
349 struct host1x_client *client, *cl;
351 mutex_lock(&device->subdevs_lock);
353 /* unregister subdevices */
354 list_for_each_entry_safe(subdev, sd, &device->active, list) {
356 * host1x_subdev_unregister() will remove the client from
357 * any lists, so we'll need to manually add it back to the
358 * list of idle clients.
360 * XXX: Alternatively, perhaps don't remove the client from
361 * any lists in host1x_subdev_unregister() and instead do
362 * that explicitly from host1x_unregister_client()?
364 client = subdev->client;
366 __host1x_subdev_unregister(device, subdev);
368 /* add the client to the list of idle clients */
369 mutex_lock(&clients_lock);
370 list_add_tail(&client->list, &clients);
371 mutex_unlock(&clients_lock);
374 /* remove subdevices */
375 list_for_each_entry_safe(subdev, sd, &device->subdevs, list)
376 host1x_subdev_del(subdev);
378 mutex_unlock(&device->subdevs_lock);
380 /* move clients to idle list */
381 mutex_lock(&clients_lock);
382 mutex_lock(&device->clients_lock);
384 list_for_each_entry_safe(client, cl, &device->clients, list)
385 list_move_tail(&client->list, &clients);
387 mutex_unlock(&device->clients_lock);
388 mutex_unlock(&clients_lock);
390 /* finally remove the device */
391 list_del_init(&device->list);
392 device_unregister(&device->dev);
395 static void host1x_attach_driver(struct host1x *host1x,
396 struct host1x_driver *driver)
398 struct host1x_device *device;
401 mutex_lock(&host1x->devices_lock);
403 list_for_each_entry(device, &host1x->devices, list) {
404 if (device->driver == driver) {
405 mutex_unlock(&host1x->devices_lock);
410 mutex_unlock(&host1x->devices_lock);
412 err = host1x_device_add(host1x, driver);
414 dev_err(host1x->dev, "failed to allocate device: %d\n", err);
417 static void host1x_detach_driver(struct host1x *host1x,
418 struct host1x_driver *driver)
420 struct host1x_device *device, *tmp;
422 mutex_lock(&host1x->devices_lock);
424 list_for_each_entry_safe(device, tmp, &host1x->devices, list)
425 if (device->driver == driver)
426 host1x_device_del(host1x, device);
428 mutex_unlock(&host1x->devices_lock);
431 int host1x_register(struct host1x *host1x)
433 struct host1x_driver *driver;
435 mutex_lock(&devices_lock);
436 list_add_tail(&host1x->list, &devices);
437 mutex_unlock(&devices_lock);
439 mutex_lock(&drivers_lock);
441 list_for_each_entry(driver, &drivers, list)
442 host1x_attach_driver(host1x, driver);
444 mutex_unlock(&drivers_lock);
449 int host1x_unregister(struct host1x *host1x)
451 struct host1x_driver *driver;
453 mutex_lock(&drivers_lock);
455 list_for_each_entry(driver, &drivers, list)
456 host1x_detach_driver(host1x, driver);
458 mutex_unlock(&drivers_lock);
460 mutex_lock(&devices_lock);
461 list_del_init(&host1x->list);
462 mutex_unlock(&devices_lock);
467 int host1x_driver_register(struct host1x_driver *driver)
469 struct host1x *host1x;
471 INIT_LIST_HEAD(&driver->list);
473 mutex_lock(&drivers_lock);
474 list_add_tail(&driver->list, &drivers);
475 mutex_unlock(&drivers_lock);
477 mutex_lock(&devices_lock);
479 list_for_each_entry(host1x, &devices, list)
480 host1x_attach_driver(host1x, driver);
482 mutex_unlock(&devices_lock);
486 EXPORT_SYMBOL(host1x_driver_register);
488 void host1x_driver_unregister(struct host1x_driver *driver)
490 mutex_lock(&drivers_lock);
491 list_del_init(&driver->list);
492 mutex_unlock(&drivers_lock);
494 EXPORT_SYMBOL(host1x_driver_unregister);
496 int host1x_client_register(struct host1x_client *client)
498 struct host1x *host1x;
501 mutex_lock(&devices_lock);
503 list_for_each_entry(host1x, &devices, list) {
504 err = host1x_register_client(host1x, client);
506 mutex_unlock(&devices_lock);
511 mutex_unlock(&devices_lock);
513 mutex_lock(&clients_lock);
514 list_add_tail(&client->list, &clients);
515 mutex_unlock(&clients_lock);
519 EXPORT_SYMBOL(host1x_client_register);
521 int host1x_client_unregister(struct host1x_client *client)
523 struct host1x_client *c;
524 struct host1x *host1x;
527 mutex_lock(&devices_lock);
529 list_for_each_entry(host1x, &devices, list) {
530 err = host1x_unregister_client(host1x, client);
532 mutex_unlock(&devices_lock);
537 mutex_unlock(&devices_lock);
538 mutex_lock(&clients_lock);
540 list_for_each_entry(c, &clients, list) {
542 list_del_init(&c->list);
547 mutex_unlock(&clients_lock);
551 EXPORT_SYMBOL(host1x_client_unregister);