summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/host1x/bus.c
blob: c27858ae05529743f14e0e61104af96476a55ad3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
/*
 * Copyright (C) 2012 Avionic Design GmbH
 * Copyright (C) 2012-2013, NVIDIA Corporation
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/host1x.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/of_device.h>

#include "bus.h"
#include "dev.h"

static DEFINE_MUTEX(clients_lock);
static LIST_HEAD(clients);

static DEFINE_MUTEX(drivers_lock);
static LIST_HEAD(drivers);

static DEFINE_MUTEX(devices_lock);
static LIST_HEAD(devices);

struct host1x_subdev {
	struct host1x_client *client;
	struct device_node *np;
	struct list_head list;
};

/**
 * host1x_subdev_add() - add a new subdevice with an associated device node
 */
static int host1x_subdev_add(struct host1x_device *device,
			     struct device_node *np)
{
	struct host1x_subdev *subdev;

	subdev = kzalloc(sizeof(*subdev), GFP_KERNEL);
	if (!subdev)
		return -ENOMEM;

	INIT_LIST_HEAD(&subdev->list);
	subdev->np = of_node_get(np);

	mutex_lock(&device->subdevs_lock);
	list_add_tail(&subdev->list, &device->subdevs);
	mutex_unlock(&device->subdevs_lock);

	return 0;
}

/**
 * host1x_subdev_del() - remove subdevice
 */
static void host1x_subdev_del(struct host1x_subdev *subdev)
{
	list_del(&subdev->list);
	of_node_put(subdev->np);
	kfree(subdev);
}

/**
 * host1x_device_parse_dt() - scan device tree and add matching subdevices
 */
static int host1x_device_parse_dt(struct host1x_device *device,
				  struct host1x_driver *driver)
{
	struct device_node *np;
	int err;

	for_each_child_of_node(device->dev.parent->of_node, np) {
		if (of_match_node(driver->subdevs, np) &&
		    of_device_is_available(np)) {
			err = host1x_subdev_add(device, np);
			if (err < 0) {
				of_node_put(np);
				return err;
			}
		}
	}

	return 0;
}

static void host1x_subdev_register(struct host1x_device *device,
				   struct host1x_subdev *subdev,
				   struct host1x_client *client)
{
	int err;

	/*
	 * Move the subdevice to the list of active (registered) subdevices
	 * and associate it with a client. At the same time, associate the
	 * client with its parent device.
	 */
	mutex_lock(&device->subdevs_lock);
	mutex_lock(&device->clients_lock);
	list_move_tail(&client->list, &device->clients);
	list_move_tail(&subdev->list, &device->active);
	client->parent = &device->dev;
	subdev->client = client;
	mutex_unlock(&device->clients_lock);
	mutex_unlock(&device->subdevs_lock);

	if (list_empty(&device->subdevs)) {
		err = device_add(&device->dev);
		if (err < 0)
			dev_err(&device->dev, "failed to add: %d\n", err);
		else
			device->registered = true;
	}
}

static void __host1x_subdev_unregister(struct host1x_device *device,
				       struct host1x_subdev *subdev)
{
	struct host1x_client *client = subdev->client;

	/*
	 * If all subdevices have been activated, we're about to remove the
	 * first active subdevice, so unload the driver first.
	 */
	if (list_empty(&device->subdevs)) {
		if (device->registered) {
			device->registered = false;
			device_del(&device->dev);
		}
	}

	/*
	 * Move the subdevice back to the list of idle subdevices and remove
	 * it from list of clients.
	 */
	mutex_lock(&device->clients_lock);
	subdev->client = NULL;
	client->parent = NULL;
	list_move_tail(&subdev->list, &device->subdevs);
	/*
	 * XXX: Perhaps don't do this here, but rather explicitly remove it
	 * when the device is about to be deleted.
	 *
	 * This is somewhat complicated by the fact that this function is
	 * used to remove the subdevice when a client is unregistered but
	 * also when the composite device is about to be removed.
	 */
	list_del_init(&client->list);
	mutex_unlock(&device->clients_lock);
}

static void host1x_subdev_unregister(struct host1x_device *device,
				     struct host1x_subdev *subdev)
{
	mutex_lock(&device->subdevs_lock);
	__host1x_subdev_unregister(device, subdev);
	mutex_unlock(&device->subdevs_lock);
}

int host1x_device_init(struct host1x_device *device)
{
	struct host1x_client *client;
	int err;

	mutex_lock(&device->clients_lock);

	list_for_each_entry(client, &device->clients, list) {
		if (client->ops && client->ops->init) {
			err = client->ops->init(client);
			if (err < 0) {
				dev_err(&device->dev,
					"failed to initialize %s: %d\n",
					dev_name(client->dev), err);
				mutex_unlock(&device->clients_lock);
				return err;
			}
		}
	}

	mutex_unlock(&device->clients_lock);

	return 0;
}
EXPORT_SYMBOL(host1x_device_init);

int host1x_device_exit(struct host1x_device *device)
{
	struct host1x_client *client;
	int err;

	mutex_lock(&device->clients_lock);

	list_for_each_entry_reverse(client, &device->clients, list) {
		if (client->ops && client->ops->exit) {
			err = client->ops->exit(client);
			if (err < 0) {
				dev_err(&device->dev,
					"failed to cleanup %s: %d\n",
					dev_name(client->dev), err);
				mutex_unlock(&device->clients_lock);
				return err;
			}
		}
	}

	mutex_unlock(&device->clients_lock);

	return 0;
}
EXPORT_SYMBOL(host1x_device_exit);

static int host1x_add_client(struct host1x *host1x,
			     struct host1x_client *client)
{
	struct host1x_device *device;
	struct host1x_subdev *subdev;

	mutex_lock(&host1x->devices_lock);

	list_for_each_entry(device, &host1x->devices, list) {
		list_for_each_entry(subdev, &device->subdevs, list) {
			if (subdev->np == client->dev->of_node) {
				host1x_subdev_register(device, subdev, client);
				mutex_unlock(&host1x->devices_lock);
				return 0;
			}
		}
	}

	mutex_unlock(&host1x->devices_lock);
	return -ENODEV;
}

static int host1x_del_client(struct host1x *host1x,
			     struct host1x_client *client)
{
	struct host1x_device *device, *dt;
	struct host1x_subdev *subdev;

	mutex_lock(&host1x->devices_lock);

	list_for_each_entry_safe(device, dt, &host1x->devices, list) {
		list_for_each_entry(subdev, &device->active, list) {
			if (subdev->client == client) {
				host1x_subdev_unregister(device, subdev);
				mutex_unlock(&host1x->devices_lock);
				return 0;
			}
		}
	}

	mutex_unlock(&host1x->devices_lock);
	return -ENODEV;
}

static int host1x_device_match(struct device *dev, struct device_driver *drv)
{
	return strcmp(dev_name(dev), drv->name) == 0;
}

static int host1x_device_probe(struct device *dev)
{
	struct host1x_driver *driver = to_host1x_driver(dev->driver);
	struct host1x_device *device = to_host1x_device(dev);

	if (driver->probe)
		return driver->probe(device);

	return 0;
}

static int host1x_device_remove(struct device *dev)
{
	struct host1x_driver *driver = to_host1x_driver(dev->driver);
	struct host1x_device *device = to_host1x_device(dev);

	if (driver->remove)
		return driver->remove(device);

	return 0;
}

static void host1x_device_shutdown(struct device *dev)
{
	struct host1x_driver *driver = to_host1x_driver(dev->driver);
	struct host1x_device *device = to_host1x_device(dev);

	if (driver->shutdown)
		driver->shutdown(device);
}

static const struct dev_pm_ops host1x_device_pm_ops = {
	.suspend = pm_generic_suspend,
	.resume = pm_generic_resume,
	.freeze = pm_generic_freeze,
	.thaw = pm_generic_thaw,
	.poweroff = pm_generic_poweroff,
	.restore = pm_generic_restore,
};

struct bus_type host1x_bus_type = {
	.name = "host1x",
	.match = host1x_device_match,
	.probe = host1x_device_probe,
	.remove = host1x_device_remove,
	.shutdown = host1x_device_shutdown,
	.pm = &host1x_device_pm_ops,
};

static void __host1x_device_del(struct host1x_device *device)
{
	struct host1x_subdev *subdev, *sd;
	struct host1x_client *client, *cl;

	mutex_lock(&device->subdevs_lock);

	/* unregister subdevices */
	list_for_each_entry_safe(subdev, sd, &device->active, list) {
		/*
		 * host1x_subdev_unregister() will remove the client from
		 * any lists, so we'll need to manually add it back to the
		 * list of idle clients.
		 *
		 * XXX: Alternatively, perhaps don't remove the client from
		 * any lists in host1x_subdev_unregister() and instead do
		 * that explicitly from host1x_unregister_client()?
		 */
		client = subdev->client;

		__host1x_subdev_unregister(device, subdev);

		/* add the client to the list of idle clients */
		mutex_lock(&clients_lock);
		list_add_tail(&client->list, &clients);
		mutex_unlock(&clients_lock);
	}

	/* remove subdevices */
	list_for_each_entry_safe(subdev, sd, &device->subdevs, list)
		host1x_subdev_del(subdev);

	mutex_unlock(&device->subdevs_lock);

	/* move clients to idle list */
	mutex_lock(&clients_lock);
	mutex_lock(&device->clients_lock);

	list_for_each_entry_safe(client, cl, &device->clients, list)
		list_move_tail(&client->list, &clients);

	mutex_unlock(&device->clients_lock);
	mutex_unlock(&clients_lock);

	/* finally remove the device */
	list_del_init(&device->list);
}

static void host1x_device_release(struct device *dev)
{
	struct host1x_device *device = to_host1x_device(dev);

	__host1x_device_del(device);
	kfree(device);
}

static int host1x_device_add(struct host1x *host1x,
			     struct host1x_driver *driver)
{
	struct host1x_client *client, *tmp;
	struct host1x_subdev *subdev;
	struct host1x_device *device;
	int err;

	device = kzalloc(sizeof(*device), GFP_KERNEL);
	if (!device)
		return -ENOMEM;

	device_initialize(&device->dev);

	mutex_init(&device->subdevs_lock);
	INIT_LIST_HEAD(&device->subdevs);
	INIT_LIST_HEAD(&device->active);
	mutex_init(&device->clients_lock);
	INIT_LIST_HEAD(&device->clients);
	INIT_LIST_HEAD(&device->list);
	device->driver = driver;

	device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask;
	device->dev.dma_mask = &device->dev.coherent_dma_mask;
	dev_set_name(&device->dev, "%s", driver->driver.name);
	of_dma_configure(&device->dev, host1x->dev->of_node);
	device->dev.release = host1x_device_release;
	device->dev.bus = &host1x_bus_type;
	device->dev.parent = host1x->dev;

	err = host1x_device_parse_dt(device, driver);
	if (err < 0) {
		kfree(device);
		return err;
	}

	list_add_tail(&device->list, &host1x->devices);

	mutex_lock(&clients_lock);

	list_for_each_entry_safe(client, tmp, &clients, list) {
		list_for_each_entry(subdev, &device->subdevs, list) {
			if (subdev->np == client->dev->of_node) {
				host1x_subdev_register(device, subdev, client);
				break;
			}
		}
	}

	mutex_unlock(&clients_lock);

	return 0;
}

/*
 * Removes a device by first unregistering any subdevices and then removing
 * itself from the list of devices.
 *
 * This function must be called with the host1x->devices_lock held.
 */
static void host1x_device_del(struct host1x *host1x,
			      struct host1x_device *device)
{
	if (device->registered) {
		device->registered = false;
		device_del(&device->dev);
	}

	put_device(&device->dev);
}

static void host1x_attach_driver(struct host1x *host1x,
				 struct host1x_driver *driver)
{
	struct host1x_device *device;
	int err;

	mutex_lock(&host1x->devices_lock);

	list_for_each_entry(device, &host1x->devices, list) {
		if (device->driver == driver) {
			mutex_unlock(&host1x->devices_lock);
			return;
		}
	}

	err = host1x_device_add(host1x, driver);
	if (err < 0)
		dev_err(host1x->dev, "failed to allocate device: %d\n", err);

	mutex_unlock(&host1x->devices_lock);
}

static void host1x_detach_driver(struct host1x *host1x,
				 struct host1x_driver *driver)
{
	struct host1x_device *device, *tmp;

	mutex_lock(&host1x->devices_lock);

	list_for_each_entry_safe(device, tmp, &host1x->devices, list)
		if (device->driver == driver)
			host1x_device_del(host1x, device);

	mutex_unlock(&host1x->devices_lock);
}

int host1x_register(struct host1x *host1x)
{
	struct host1x_driver *driver;

	mutex_lock(&devices_lock);
	list_add_tail(&host1x->list, &devices);
	mutex_unlock(&devices_lock);

	mutex_lock(&drivers_lock);

	list_for_each_entry(driver, &drivers, list)
		host1x_attach_driver(host1x, driver);

	mutex_unlock(&drivers_lock);

	return 0;
}

int host1x_unregister(struct host1x *host1x)
{
	struct host1x_driver *driver;

	mutex_lock(&drivers_lock);

	list_for_each_entry(driver, &drivers, list)
		host1x_detach_driver(host1x, driver);

	mutex_unlock(&drivers_lock);

	mutex_lock(&devices_lock);
	list_del_init(&host1x->list);
	mutex_unlock(&devices_lock);

	return 0;
}

int host1x_driver_register_full(struct host1x_driver *driver,
				struct module *owner)
{
	struct host1x *host1x;

	INIT_LIST_HEAD(&driver->list);

	mutex_lock(&drivers_lock);
	list_add_tail(&driver->list, &drivers);
	mutex_unlock(&drivers_lock);

	mutex_lock(&devices_lock);

	list_for_each_entry(host1x, &devices, list)
		host1x_attach_driver(host1x, driver);

	mutex_unlock(&devices_lock);

	driver->driver.bus = &host1x_bus_type;
	driver->driver.owner = owner;

	return driver_register(&driver->driver);
}
EXPORT_SYMBOL(host1x_driver_register_full);

void host1x_driver_unregister(struct host1x_driver *driver)
{
	driver_unregister(&driver->driver);

	mutex_lock(&drivers_lock);
	list_del_init(&driver->list);
	mutex_unlock(&drivers_lock);
}
EXPORT_SYMBOL(host1x_driver_unregister);

int host1x_client_register(struct host1x_client *client)
{
	struct host1x *host1x;
	int err;

	mutex_lock(&devices_lock);

	list_for_each_entry(host1x, &devices, list) {
		err = host1x_add_client(host1x, client);
		if (!err) {
			mutex_unlock(&devices_lock);
			return 0;
		}
	}

	mutex_unlock(&devices_lock);

	mutex_lock(&clients_lock);
	list_add_tail(&client->list, &clients);
	mutex_unlock(&clients_lock);

	return 0;
}
EXPORT_SYMBOL(host1x_client_register);

int host1x_client_unregister(struct host1x_client *client)
{
	struct host1x_client *c;
	struct host1x *host1x;
	int err;

	mutex_lock(&devices_lock);

	list_for_each_entry(host1x, &devices, list) {
		err = host1x_del_client(host1x, client);
		if (!err) {
			mutex_unlock(&devices_lock);
			return 0;
		}
	}

	mutex_unlock(&devices_lock);
	mutex_lock(&clients_lock);

	list_for_each_entry(c, &clients, list) {
		if (c == client) {
			list_del_init(&c->list);
			break;
		}
	}

	mutex_unlock(&clients_lock);

	return 0;
}
EXPORT_SYMBOL(host1x_client_unregister);