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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
17static DEFINE_MUTEX(clients_lock);
18static LIST_HEAD(clients);
19
20static DEFINE_MUTEX(drivers_lock);
21static LIST_HEAD(drivers);
22
23static DEFINE_MUTEX(devices_lock);
24static LIST_HEAD(devices);
25
26struct 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 * @np: device node
36 */
37static int host1x_subdev_add(struct host1x_device *device,
38 struct host1x_driver *driver,
39 struct device_node *np)
40{
41 struct host1x_subdev *subdev;
42 struct device_node *child;
43 int err;
44
45 subdev = kzalloc(sizeof(*subdev), GFP_KERNEL);
46 if (!subdev)
47 return -ENOMEM;
48
49 INIT_LIST_HEAD(&subdev->list);
50 subdev->np = of_node_get(np);
51
52 mutex_lock(&device->subdevs_lock);
53 list_add_tail(&subdev->list, &device->subdevs);
54 mutex_unlock(&device->subdevs_lock);
55
56 /* recursively add children */
57 for_each_child_of_node(np, child) {
58 if (of_match_node(driver->subdevs, child) &&
59 of_device_is_available(child)) {
60 err = host1x_subdev_add(device, driver, child);
61 if (err < 0) {
62 /* XXX cleanup? */
63 of_node_put(child);
64 return err;
65 }
66 }
67 }
68
69 return 0;
70}
71
72/**
73 * host1x_subdev_del() - remove subdevice
74 * @subdev: subdevice to remove
75 */
76static void host1x_subdev_del(struct host1x_subdev *subdev)
77{
78 list_del(&subdev->list);
79 of_node_put(subdev->np);
80 kfree(subdev);
81}
82
83/**
84 * host1x_device_parse_dt() - scan device tree and add matching subdevices
85 * @device: host1x logical device
86 * @driver: host1x driver
87 */
88static int host1x_device_parse_dt(struct host1x_device *device,
89 struct host1x_driver *driver)
90{
91 struct device_node *np;
92 int err;
93
94 for_each_child_of_node(device->dev.parent->of_node, np) {
95 if (of_match_node(driver->subdevs, np) &&
96 of_device_is_available(np)) {
97 err = host1x_subdev_add(device, driver, np);
98 if (err < 0) {
99 of_node_put(np);
100 return err;
101 }
102 }
103 }
104
105 return 0;
106}
107
108static void host1x_subdev_register(struct host1x_device *device,
109 struct host1x_subdev *subdev,
110 struct host1x_client *client)
111{
112 int err;
113
114 /*
115 * Move the subdevice to the list of active (registered) subdevices
116 * and associate it with a client. At the same time, associate the
117 * client with its parent device.
118 */
119 mutex_lock(&device->subdevs_lock);
120 mutex_lock(&device->clients_lock);
121 list_move_tail(&client->list, &device->clients);
122 list_move_tail(&subdev->list, &device->active);
123 client->host = &device->dev;
124 subdev->client = client;
125 mutex_unlock(&device->clients_lock);
126 mutex_unlock(&device->subdevs_lock);
127
128 if (list_empty(&device->subdevs)) {
129 err = device_add(&device->dev);
130 if (err < 0)
131 dev_err(&device->dev, "failed to add: %d\n", err);
132 else
133 device->registered = true;
134 }
135}
136
137static void __host1x_subdev_unregister(struct host1x_device *device,
138 struct host1x_subdev *subdev)
139{
140 struct host1x_client *client = subdev->client;
141
142 /*
143 * If all subdevices have been activated, we're about to remove the
144 * first active subdevice, so unload the driver first.
145 */
146 if (list_empty(&device->subdevs)) {
147 if (device->registered) {
148 device->registered = false;
149 device_del(&device->dev);
150 }
151 }
152
153 /*
154 * Move the subdevice back to the list of idle subdevices and remove
155 * it from list of clients.
156 */
157 mutex_lock(&device->clients_lock);
158 subdev->client = NULL;
159 client->host = NULL;
160 list_move_tail(&subdev->list, &device->subdevs);
161 /*
162 * XXX: Perhaps don't do this here, but rather explicitly remove it
163 * when the device is about to be deleted.
164 *
165 * This is somewhat complicated by the fact that this function is
166 * used to remove the subdevice when a client is unregistered but
167 * also when the composite device is about to be removed.
168 */
169 list_del_init(&client->list);
170 mutex_unlock(&device->clients_lock);
171}
172
173static void host1x_subdev_unregister(struct host1x_device *device,
174 struct host1x_subdev *subdev)
175{
176 mutex_lock(&device->subdevs_lock);
177 __host1x_subdev_unregister(device, subdev);
178 mutex_unlock(&device->subdevs_lock);
179}
180
181/**
182 * host1x_device_init() - initialize a host1x logical device
183 * @device: host1x logical device
184 *
185 * The driver for the host1x logical device can call this during execution of
186 * its &host1x_driver.probe implementation to initialize each of its clients.
187 * The client drivers access the subsystem specific driver data using the
188 * &host1x_client.parent field and driver data associated with it (usually by
189 * calling dev_get_drvdata()).
190 */
191int host1x_device_init(struct host1x_device *device)
192{
193 struct host1x_client *client;
194 int err;
195
196 mutex_lock(&device->clients_lock);
197
198 list_for_each_entry(client, &device->clients, list) {
199 if (client->ops && client->ops->init) {
200 err = client->ops->init(client);
201 if (err < 0) {
202 dev_err(&device->dev,
203 "failed to initialize %s: %d\n",
204 dev_name(client->dev), err);
205 goto teardown;
206 }
207 }
208 }
209
210 mutex_unlock(&device->clients_lock);
211
212 return 0;
213
214teardown:
215 list_for_each_entry_continue_reverse(client, &device->clients, list)
216 if (client->ops->exit)
217 client->ops->exit(client);
218
219 mutex_unlock(&device->clients_lock);
220 return err;
221}
222EXPORT_SYMBOL(host1x_device_init);
223
224/**
225 * host1x_device_exit() - uninitialize host1x logical device
226 * @device: host1x logical device
227 *
228 * When the driver for a host1x logical device is unloaded, it can call this
229 * function to tear down each of its clients. Typically this is done after a
230 * subsystem-specific data structure is removed and the functionality can no
231 * longer be used.
232 */
233int host1x_device_exit(struct host1x_device *device)
234{
235 struct host1x_client *client;
236 int err;
237
238 mutex_lock(&device->clients_lock);
239
240 list_for_each_entry_reverse(client, &device->clients, list) {
241 if (client->ops && client->ops->exit) {
242 err = client->ops->exit(client);
243 if (err < 0) {
244 dev_err(&device->dev,
245 "failed to cleanup %s: %d\n",
246 dev_name(client->dev), err);
247 mutex_unlock(&device->clients_lock);
248 return err;
249 }
250 }
251 }
252
253 mutex_unlock(&device->clients_lock);
254
255 return 0;
256}
257EXPORT_SYMBOL(host1x_device_exit);
258
259static int host1x_add_client(struct host1x *host1x,
260 struct host1x_client *client)
261{
262 struct host1x_device *device;
263 struct host1x_subdev *subdev;
264
265 mutex_lock(&host1x->devices_lock);
266
267 list_for_each_entry(device, &host1x->devices, list) {
268 list_for_each_entry(subdev, &device->subdevs, list) {
269 if (subdev->np == client->dev->of_node) {
270 host1x_subdev_register(device, subdev, client);
271 mutex_unlock(&host1x->devices_lock);
272 return 0;
273 }
274 }
275 }
276
277 mutex_unlock(&host1x->devices_lock);
278 return -ENODEV;
279}
280
281static int host1x_del_client(struct host1x *host1x,
282 struct host1x_client *client)
283{
284 struct host1x_device *device, *dt;
285 struct host1x_subdev *subdev;
286
287 mutex_lock(&host1x->devices_lock);
288
289 list_for_each_entry_safe(device, dt, &host1x->devices, list) {
290 list_for_each_entry(subdev, &device->active, list) {
291 if (subdev->client == client) {
292 host1x_subdev_unregister(device, subdev);
293 mutex_unlock(&host1x->devices_lock);
294 return 0;
295 }
296 }
297 }
298
299 mutex_unlock(&host1x->devices_lock);
300 return -ENODEV;
301}
302
303static int host1x_device_match(struct device *dev, struct device_driver *drv)
304{
305 return strcmp(dev_name(dev), drv->name) == 0;
306}
307
308static int host1x_device_uevent(struct device *dev,
309 struct kobj_uevent_env *env)
310{
311 struct device_node *np = dev->parent->of_node;
312 unsigned int count = 0;
313 struct property *p;
314 const char *compat;
315
316 /*
317 * This duplicates most of of_device_uevent(), but the latter cannot
318 * be called from modules and operates on dev->of_node, which is not
319 * available in this case.
320 *
321 * Note that this is really only needed for backwards compatibility
322 * with libdrm, which parses this information from sysfs and will
323 * fail if it can't find the OF_FULLNAME, specifically.
324 */
325 add_uevent_var(env, "OF_NAME=%pOFn", np);
326 add_uevent_var(env, "OF_FULLNAME=%pOF", np);
327
328 of_property_for_each_string(np, "compatible", p, compat) {
329 add_uevent_var(env, "OF_COMPATIBLE_%u=%s", count, compat);
330 count++;
331 }
332
333 add_uevent_var(env, "OF_COMPATIBLE_N=%u", count);
334
335 return 0;
336}
337
338static int host1x_dma_configure(struct device *dev)
339{
340 return of_dma_configure(dev, dev->of_node, true);
341}
342
343static const struct dev_pm_ops host1x_device_pm_ops = {
344 .suspend = pm_generic_suspend,
345 .resume = pm_generic_resume,
346 .freeze = pm_generic_freeze,
347 .thaw = pm_generic_thaw,
348 .poweroff = pm_generic_poweroff,
349 .restore = pm_generic_restore,
350};
351
352struct bus_type host1x_bus_type = {
353 .name = "host1x",
354 .match = host1x_device_match,
355 .uevent = host1x_device_uevent,
356 .dma_configure = host1x_dma_configure,
357 .pm = &host1x_device_pm_ops,
358};
359
360static void __host1x_device_del(struct host1x_device *device)
361{
362 struct host1x_subdev *subdev, *sd;
363 struct host1x_client *client, *cl;
364
365 mutex_lock(&device->subdevs_lock);
366
367 /* unregister subdevices */
368 list_for_each_entry_safe(subdev, sd, &device->active, list) {
369 /*
370 * host1x_subdev_unregister() will remove the client from
371 * any lists, so we'll need to manually add it back to the
372 * list of idle clients.
373 *
374 * XXX: Alternatively, perhaps don't remove the client from
375 * any lists in host1x_subdev_unregister() and instead do
376 * that explicitly from host1x_unregister_client()?
377 */
378 client = subdev->client;
379
380 __host1x_subdev_unregister(device, subdev);
381
382 /* add the client to the list of idle clients */
383 mutex_lock(&clients_lock);
384 list_add_tail(&client->list, &clients);
385 mutex_unlock(&clients_lock);
386 }
387
388 /* remove subdevices */
389 list_for_each_entry_safe(subdev, sd, &device->subdevs, list)
390 host1x_subdev_del(subdev);
391
392 mutex_unlock(&device->subdevs_lock);
393
394 /* move clients to idle list */
395 mutex_lock(&clients_lock);
396 mutex_lock(&device->clients_lock);
397
398 list_for_each_entry_safe(client, cl, &device->clients, list)
399 list_move_tail(&client->list, &clients);
400
401 mutex_unlock(&device->clients_lock);
402 mutex_unlock(&clients_lock);
403
404 /* finally remove the device */
405 list_del_init(&device->list);
406}
407
408static void host1x_device_release(struct device *dev)
409{
410 struct host1x_device *device = to_host1x_device(dev);
411
412 __host1x_device_del(device);
413 kfree(device);
414}
415
416static int host1x_device_add(struct host1x *host1x,
417 struct host1x_driver *driver)
418{
419 struct host1x_client *client, *tmp;
420 struct host1x_subdev *subdev;
421 struct host1x_device *device;
422 int err;
423
424 device = kzalloc(sizeof(*device), GFP_KERNEL);
425 if (!device)
426 return -ENOMEM;
427
428 device_initialize(&device->dev);
429
430 mutex_init(&device->subdevs_lock);
431 INIT_LIST_HEAD(&device->subdevs);
432 INIT_LIST_HEAD(&device->active);
433 mutex_init(&device->clients_lock);
434 INIT_LIST_HEAD(&device->clients);
435 INIT_LIST_HEAD(&device->list);
436 device->driver = driver;
437
438 device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask;
439 device->dev.dma_mask = &device->dev.coherent_dma_mask;
440 dev_set_name(&device->dev, "%s", driver->driver.name);
441 device->dev.release = host1x_device_release;
442 device->dev.bus = &host1x_bus_type;
443 device->dev.parent = host1x->dev;
444
445 of_dma_configure(&device->dev, host1x->dev->of_node, true);
446
447 device->dev.dma_parms = &device->dma_parms;
448 dma_set_max_seg_size(&device->dev, UINT_MAX);
449
450 err = host1x_device_parse_dt(device, driver);
451 if (err < 0) {
452 kfree(device);
453 return err;
454 }
455
456 list_add_tail(&device->list, &host1x->devices);
457
458 mutex_lock(&clients_lock);
459
460 list_for_each_entry_safe(client, tmp, &clients, list) {
461 list_for_each_entry(subdev, &device->subdevs, list) {
462 if (subdev->np == client->dev->of_node) {
463 host1x_subdev_register(device, subdev, client);
464 break;
465 }
466 }
467 }
468
469 mutex_unlock(&clients_lock);
470
471 return 0;
472}
473
474/*
475 * Removes a device by first unregistering any subdevices and then removing
476 * itself from the list of devices.
477 *
478 * This function must be called with the host1x->devices_lock held.
479 */
480static void host1x_device_del(struct host1x *host1x,
481 struct host1x_device *device)
482{
483 if (device->registered) {
484 device->registered = false;
485 device_del(&device->dev);
486 }
487
488 put_device(&device->dev);
489}
490
491static void host1x_attach_driver(struct host1x *host1x,
492 struct host1x_driver *driver)
493{
494 struct host1x_device *device;
495 int err;
496
497 mutex_lock(&host1x->devices_lock);
498
499 list_for_each_entry(device, &host1x->devices, list) {
500 if (device->driver == driver) {
501 mutex_unlock(&host1x->devices_lock);
502 return;
503 }
504 }
505
506 err = host1x_device_add(host1x, driver);
507 if (err < 0)
508 dev_err(host1x->dev, "failed to allocate device: %d\n", err);
509
510 mutex_unlock(&host1x->devices_lock);
511}
512
513static void host1x_detach_driver(struct host1x *host1x,
514 struct host1x_driver *driver)
515{
516 struct host1x_device *device, *tmp;
517
518 mutex_lock(&host1x->devices_lock);
519
520 list_for_each_entry_safe(device, tmp, &host1x->devices, list)
521 if (device->driver == driver)
522 host1x_device_del(host1x, device);
523
524 mutex_unlock(&host1x->devices_lock);
525}
526
527static int host1x_devices_show(struct seq_file *s, void *data)
528{
529 struct host1x *host1x = s->private;
530 struct host1x_device *device;
531
532 mutex_lock(&host1x->devices_lock);
533
534 list_for_each_entry(device, &host1x->devices, list) {
535 struct host1x_subdev *subdev;
536
537 seq_printf(s, "%s\n", dev_name(&device->dev));
538
539 mutex_lock(&device->subdevs_lock);
540
541 list_for_each_entry(subdev, &device->active, list)
542 seq_printf(s, " %pOFf: %s\n", subdev->np,
543 dev_name(subdev->client->dev));
544
545 list_for_each_entry(subdev, &device->subdevs, list)
546 seq_printf(s, " %pOFf:\n", subdev->np);
547
548 mutex_unlock(&device->subdevs_lock);
549 }
550
551 mutex_unlock(&host1x->devices_lock);
552
553 return 0;
554}
555DEFINE_SHOW_ATTRIBUTE(host1x_devices);
556
557/**
558 * host1x_register() - register a host1x controller
559 * @host1x: host1x controller
560 *
561 * The host1x controller driver uses this to register a host1x controller with
562 * the infrastructure. Note that all Tegra SoC generations have only ever come
563 * with a single host1x instance, so this function is somewhat academic.
564 */
565int host1x_register(struct host1x *host1x)
566{
567 struct host1x_driver *driver;
568
569 mutex_lock(&devices_lock);
570 list_add_tail(&host1x->list, &devices);
571 mutex_unlock(&devices_lock);
572
573 mutex_lock(&drivers_lock);
574
575 list_for_each_entry(driver, &drivers, list)
576 host1x_attach_driver(host1x, driver);
577
578 mutex_unlock(&drivers_lock);
579
580 debugfs_create_file("devices", S_IRUGO, host1x->debugfs, host1x,
581 &host1x_devices_fops);
582
583 return 0;
584}
585
586/**
587 * host1x_unregister() - unregister a host1x controller
588 * @host1x: host1x controller
589 *
590 * The host1x controller driver uses this to remove a host1x controller from
591 * the infrastructure.
592 */
593int host1x_unregister(struct host1x *host1x)
594{
595 struct host1x_driver *driver;
596
597 mutex_lock(&drivers_lock);
598
599 list_for_each_entry(driver, &drivers, list)
600 host1x_detach_driver(host1x, driver);
601
602 mutex_unlock(&drivers_lock);
603
604 mutex_lock(&devices_lock);
605 list_del_init(&host1x->list);
606 mutex_unlock(&devices_lock);
607
608 return 0;
609}
610
611static int host1x_device_probe(struct device *dev)
612{
613 struct host1x_driver *driver = to_host1x_driver(dev->driver);
614 struct host1x_device *device = to_host1x_device(dev);
615
616 if (driver->probe)
617 return driver->probe(device);
618
619 return 0;
620}
621
622static int host1x_device_remove(struct device *dev)
623{
624 struct host1x_driver *driver = to_host1x_driver(dev->driver);
625 struct host1x_device *device = to_host1x_device(dev);
626
627 if (driver->remove)
628 return driver->remove(device);
629
630 return 0;
631}
632
633static void host1x_device_shutdown(struct device *dev)
634{
635 struct host1x_driver *driver = to_host1x_driver(dev->driver);
636 struct host1x_device *device = to_host1x_device(dev);
637
638 if (driver->shutdown)
639 driver->shutdown(device);
640}
641
642/**
643 * host1x_driver_register_full() - register a host1x driver
644 * @driver: host1x driver
645 * @owner: owner module
646 *
647 * Drivers for host1x logical devices call this function to register a driver
648 * with the infrastructure. Note that since these drive logical devices, the
649 * registration of the driver actually triggers tho logical device creation.
650 * A logical device will be created for each host1x instance.
651 */
652int host1x_driver_register_full(struct host1x_driver *driver,
653 struct module *owner)
654{
655 struct host1x *host1x;
656
657 INIT_LIST_HEAD(&driver->list);
658
659 mutex_lock(&drivers_lock);
660 list_add_tail(&driver->list, &drivers);
661 mutex_unlock(&drivers_lock);
662
663 mutex_lock(&devices_lock);
664
665 list_for_each_entry(host1x, &devices, list)
666 host1x_attach_driver(host1x, driver);
667
668 mutex_unlock(&devices_lock);
669
670 driver->driver.bus = &host1x_bus_type;
671 driver->driver.owner = owner;
672 driver->driver.probe = host1x_device_probe;
673 driver->driver.remove = host1x_device_remove;
674 driver->driver.shutdown = host1x_device_shutdown;
675
676 return driver_register(&driver->driver);
677}
678EXPORT_SYMBOL(host1x_driver_register_full);
679
680/**
681 * host1x_driver_unregister() - unregister a host1x driver
682 * @driver: host1x driver
683 *
684 * Unbinds the driver from each of the host1x logical devices that it is
685 * bound to, effectively removing the subsystem devices that they represent.
686 */
687void host1x_driver_unregister(struct host1x_driver *driver)
688{
689 struct host1x *host1x;
690
691 driver_unregister(&driver->driver);
692
693 mutex_lock(&devices_lock);
694
695 list_for_each_entry(host1x, &devices, list)
696 host1x_detach_driver(host1x, driver);
697
698 mutex_unlock(&devices_lock);
699
700 mutex_lock(&drivers_lock);
701 list_del_init(&driver->list);
702 mutex_unlock(&drivers_lock);
703}
704EXPORT_SYMBOL(host1x_driver_unregister);
705
706/**
707 * host1x_client_register() - register a host1x client
708 * @client: host1x client
709 *
710 * Registers a host1x client with each host1x controller instance. Note that
711 * each client will only match their parent host1x controller and will only be
712 * associated with that instance. Once all clients have been registered with
713 * their parent host1x controller, the infrastructure will set up the logical
714 * device and call host1x_device_init(), which will in turn call each client's
715 * &host1x_client_ops.init implementation.
716 */
717int host1x_client_register(struct host1x_client *client)
718{
719 struct host1x *host1x;
720 int err;
721
722 INIT_LIST_HEAD(&client->list);
723 mutex_init(&client->lock);
724 client->usecount = 0;
725
726 mutex_lock(&devices_lock);
727
728 list_for_each_entry(host1x, &devices, list) {
729 err = host1x_add_client(host1x, client);
730 if (!err) {
731 mutex_unlock(&devices_lock);
732 return 0;
733 }
734 }
735
736 mutex_unlock(&devices_lock);
737
738 mutex_lock(&clients_lock);
739 list_add_tail(&client->list, &clients);
740 mutex_unlock(&clients_lock);
741
742 return 0;
743}
744EXPORT_SYMBOL(host1x_client_register);
745
746/**
747 * host1x_client_unregister() - unregister a host1x client
748 * @client: host1x client
749 *
750 * Removes a host1x client from its host1x controller instance. If a logical
751 * device has already been initialized, it will be torn down.
752 */
753int host1x_client_unregister(struct host1x_client *client)
754{
755 struct host1x_client *c;
756 struct host1x *host1x;
757 int err;
758
759 mutex_lock(&devices_lock);
760
761 list_for_each_entry(host1x, &devices, list) {
762 err = host1x_del_client(host1x, client);
763 if (!err) {
764 mutex_unlock(&devices_lock);
765 return 0;
766 }
767 }
768
769 mutex_unlock(&devices_lock);
770 mutex_lock(&clients_lock);
771
772 list_for_each_entry(c, &clients, list) {
773 if (c == client) {
774 list_del_init(&c->list);
775 break;
776 }
777 }
778
779 mutex_unlock(&clients_lock);
780
781 return 0;
782}
783EXPORT_SYMBOL(host1x_client_unregister);
784
785int host1x_client_suspend(struct host1x_client *client)
786{
787 int err = 0;
788
789 mutex_lock(&client->lock);
790
791 if (client->usecount == 1) {
792 if (client->ops && client->ops->suspend) {
793 err = client->ops->suspend(client);
794 if (err < 0)
795 goto unlock;
796 }
797 }
798
799 client->usecount--;
800 dev_dbg(client->dev, "use count: %u\n", client->usecount);
801
802 if (client->parent) {
803 err = host1x_client_suspend(client->parent);
804 if (err < 0)
805 goto resume;
806 }
807
808 goto unlock;
809
810resume:
811 if (client->usecount == 0)
812 if (client->ops && client->ops->resume)
813 client->ops->resume(client);
814
815 client->usecount++;
816unlock:
817 mutex_unlock(&client->lock);
818 return err;
819}
820EXPORT_SYMBOL(host1x_client_suspend);
821
822int host1x_client_resume(struct host1x_client *client)
823{
824 int err = 0;
825
826 mutex_lock(&client->lock);
827
828 if (client->parent) {
829 err = host1x_client_resume(client->parent);
830 if (err < 0)
831 goto unlock;
832 }
833
834 if (client->usecount == 0) {
835 if (client->ops && client->ops->resume) {
836 err = client->ops->resume(client);
837 if (err < 0)
838 goto suspend;
839 }
840 }
841
842 client->usecount++;
843 dev_dbg(client->dev, "use count: %u\n", client->usecount);
844
845 goto unlock;
846
847suspend:
848 if (client->parent)
849 host1x_client_suspend(client->parent);
850unlock:
851 mutex_unlock(&client->lock);
852 return err;
853}
854EXPORT_SYMBOL(host1x_client_resume);
1/*
2 * Copyright (C) 2012 Avionic Design GmbH
3 * Copyright (C) 2012-2013, NVIDIA 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 * 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/>.
16 */
17
18#include <linux/host1x.h>
19#include <linux/of.h>
20#include <linux/slab.h>
21
22#include "bus.h"
23#include "dev.h"
24
25static DEFINE_MUTEX(clients_lock);
26static LIST_HEAD(clients);
27
28static DEFINE_MUTEX(drivers_lock);
29static LIST_HEAD(drivers);
30
31static DEFINE_MUTEX(devices_lock);
32static LIST_HEAD(devices);
33
34struct host1x_subdev {
35 struct host1x_client *client;
36 struct device_node *np;
37 struct list_head list;
38};
39
40/**
41 * host1x_subdev_add() - add a new subdevice with an associated device node
42 */
43static int host1x_subdev_add(struct host1x_device *device,
44 struct device_node *np)
45{
46 struct host1x_subdev *subdev;
47
48 subdev = kzalloc(sizeof(*subdev), GFP_KERNEL);
49 if (!subdev)
50 return -ENOMEM;
51
52 INIT_LIST_HEAD(&subdev->list);
53 subdev->np = of_node_get(np);
54
55 mutex_lock(&device->subdevs_lock);
56 list_add_tail(&subdev->list, &device->subdevs);
57 mutex_unlock(&device->subdevs_lock);
58
59 return 0;
60}
61
62/**
63 * host1x_subdev_del() - remove subdevice
64 */
65static void host1x_subdev_del(struct host1x_subdev *subdev)
66{
67 list_del(&subdev->list);
68 of_node_put(subdev->np);
69 kfree(subdev);
70}
71
72/**
73 * host1x_device_parse_dt() - scan device tree and add matching subdevices
74 */
75static int host1x_device_parse_dt(struct host1x_device *device)
76{
77 struct device_node *np;
78 int err;
79
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);
84 if (err < 0)
85 return err;
86 }
87 }
88
89 return 0;
90}
91
92static void host1x_subdev_register(struct host1x_device *device,
93 struct host1x_subdev *subdev,
94 struct host1x_client *client)
95{
96 int err;
97
98 /*
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.
102 */
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);
111
112 /*
113 * When all subdevices have been registered, the composite device is
114 * ready to be probed.
115 */
116 if (list_empty(&device->subdevs)) {
117 err = device->driver->probe(device);
118 if (err < 0)
119 dev_err(&device->dev, "probe failed: %d\n", err);
120 }
121}
122
123static void __host1x_subdev_unregister(struct host1x_device *device,
124 struct host1x_subdev *subdev)
125{
126 struct host1x_client *client = subdev->client;
127 int err;
128
129 /*
130 * If all subdevices have been activated, we're about to remove the
131 * first active subdevice, so unload the driver first.
132 */
133 if (list_empty(&device->subdevs)) {
134 err = device->driver->remove(device);
135 if (err < 0)
136 dev_err(&device->dev, "remove failed: %d\n", err);
137 }
138
139 /*
140 * Move the subdevice back to the list of idle subdevices and remove
141 * it from list of clients.
142 */
143 mutex_lock(&device->clients_lock);
144 subdev->client = NULL;
145 client->parent = NULL;
146 list_move_tail(&subdev->list, &device->subdevs);
147 /*
148 * XXX: Perhaps don't do this here, but rather explicitly remove it
149 * when the device is about to be deleted.
150 *
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.
154 */
155 list_del_init(&client->list);
156 mutex_unlock(&device->clients_lock);
157}
158
159static void host1x_subdev_unregister(struct host1x_device *device,
160 struct host1x_subdev *subdev)
161{
162 mutex_lock(&device->subdevs_lock);
163 __host1x_subdev_unregister(device, subdev);
164 mutex_unlock(&device->subdevs_lock);
165}
166
167int host1x_device_init(struct host1x_device *device)
168{
169 struct host1x_client *client;
170 int err;
171
172 mutex_lock(&device->clients_lock);
173
174 list_for_each_entry(client, &device->clients, list) {
175 if (client->ops && client->ops->init) {
176 err = client->ops->init(client);
177 if (err < 0) {
178 dev_err(&device->dev,
179 "failed to initialize %s: %d\n",
180 dev_name(client->dev), err);
181 mutex_unlock(&device->clients_lock);
182 return err;
183 }
184 }
185 }
186
187 mutex_unlock(&device->clients_lock);
188
189 return 0;
190}
191EXPORT_SYMBOL(host1x_device_init);
192
193int host1x_device_exit(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_reverse(client, &device->clients, list) {
201 if (client->ops && client->ops->exit) {
202 err = client->ops->exit(client);
203 if (err < 0) {
204 dev_err(&device->dev,
205 "failed to cleanup %s: %d\n",
206 dev_name(client->dev), err);
207 mutex_unlock(&device->clients_lock);
208 return err;
209 }
210 }
211 }
212
213 mutex_unlock(&device->clients_lock);
214
215 return 0;
216}
217EXPORT_SYMBOL(host1x_device_exit);
218
219static int host1x_register_client(struct host1x *host1x,
220 struct host1x_client *client)
221{
222 struct host1x_device *device;
223 struct host1x_subdev *subdev;
224
225 mutex_lock(&host1x->devices_lock);
226
227 list_for_each_entry(device, &host1x->devices, list) {
228 list_for_each_entry(subdev, &device->subdevs, list) {
229 if (subdev->np == client->dev->of_node) {
230 host1x_subdev_register(device, subdev, client);
231 mutex_unlock(&host1x->devices_lock);
232 return 0;
233 }
234 }
235 }
236
237 mutex_unlock(&host1x->devices_lock);
238 return -ENODEV;
239}
240
241static int host1x_unregister_client(struct host1x *host1x,
242 struct host1x_client *client)
243{
244 struct host1x_device *device, *dt;
245 struct host1x_subdev *subdev;
246
247 mutex_lock(&host1x->devices_lock);
248
249 list_for_each_entry_safe(device, dt, &host1x->devices, list) {
250 list_for_each_entry(subdev, &device->active, list) {
251 if (subdev->client == client) {
252 host1x_subdev_unregister(device, subdev);
253 mutex_unlock(&host1x->devices_lock);
254 return 0;
255 }
256 }
257 }
258
259 mutex_unlock(&host1x->devices_lock);
260 return -ENODEV;
261}
262
263static struct bus_type host1x_bus_type = {
264 .name = "host1x",
265};
266
267int host1x_bus_init(void)
268{
269 return bus_register(&host1x_bus_type);
270}
271
272void host1x_bus_exit(void)
273{
274 bus_unregister(&host1x_bus_type);
275}
276
277static void host1x_device_release(struct device *dev)
278{
279 struct host1x_device *device = to_host1x_device(dev);
280
281 kfree(device);
282}
283
284static int host1x_device_add(struct host1x *host1x,
285 struct host1x_driver *driver)
286{
287 struct host1x_client *client, *tmp;
288 struct host1x_subdev *subdev;
289 struct host1x_device *device;
290 int err;
291
292 device = kzalloc(sizeof(*device), GFP_KERNEL);
293 if (!device)
294 return -ENOMEM;
295
296 mutex_init(&device->subdevs_lock);
297 INIT_LIST_HEAD(&device->subdevs);
298 INIT_LIST_HEAD(&device->active);
299 mutex_init(&device->clients_lock);
300 INIT_LIST_HEAD(&device->clients);
301 INIT_LIST_HEAD(&device->list);
302 device->driver = driver;
303
304 device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask;
305 device->dev.dma_mask = &device->dev.coherent_dma_mask;
306 device->dev.release = host1x_device_release;
307 dev_set_name(&device->dev, "%s", driver->name);
308 device->dev.bus = &host1x_bus_type;
309 device->dev.parent = host1x->dev;
310
311 err = device_register(&device->dev);
312 if (err < 0)
313 return err;
314
315 err = host1x_device_parse_dt(device);
316 if (err < 0) {
317 device_unregister(&device->dev);
318 return err;
319 }
320
321 mutex_lock(&host1x->devices_lock);
322 list_add_tail(&device->list, &host1x->devices);
323 mutex_unlock(&host1x->devices_lock);
324
325 mutex_lock(&clients_lock);
326
327 list_for_each_entry_safe(client, tmp, &clients, list) {
328 list_for_each_entry(subdev, &device->subdevs, list) {
329 if (subdev->np == client->dev->of_node) {
330 host1x_subdev_register(device, subdev, client);
331 break;
332 }
333 }
334 }
335
336 mutex_unlock(&clients_lock);
337
338 return 0;
339}
340
341/*
342 * Removes a device by first unregistering any subdevices and then removing
343 * itself from the list of devices.
344 *
345 * This function must be called with the host1x->devices_lock held.
346 */
347static void host1x_device_del(struct host1x *host1x,
348 struct host1x_device *device)
349{
350 struct host1x_subdev *subdev, *sd;
351 struct host1x_client *client, *cl;
352
353 mutex_lock(&device->subdevs_lock);
354
355 /* unregister subdevices */
356 list_for_each_entry_safe(subdev, sd, &device->active, list) {
357 /*
358 * host1x_subdev_unregister() will remove the client from
359 * any lists, so we'll need to manually add it back to the
360 * list of idle clients.
361 *
362 * XXX: Alternatively, perhaps don't remove the client from
363 * any lists in host1x_subdev_unregister() and instead do
364 * that explicitly from host1x_unregister_client()?
365 */
366 client = subdev->client;
367
368 __host1x_subdev_unregister(device, subdev);
369
370 /* add the client to the list of idle clients */
371 mutex_lock(&clients_lock);
372 list_add_tail(&client->list, &clients);
373 mutex_unlock(&clients_lock);
374 }
375
376 /* remove subdevices */
377 list_for_each_entry_safe(subdev, sd, &device->subdevs, list)
378 host1x_subdev_del(subdev);
379
380 mutex_unlock(&device->subdevs_lock);
381
382 /* move clients to idle list */
383 mutex_lock(&clients_lock);
384 mutex_lock(&device->clients_lock);
385
386 list_for_each_entry_safe(client, cl, &device->clients, list)
387 list_move_tail(&client->list, &clients);
388
389 mutex_unlock(&device->clients_lock);
390 mutex_unlock(&clients_lock);
391
392 /* finally remove the device */
393 list_del_init(&device->list);
394 device_unregister(&device->dev);
395}
396
397static void host1x_attach_driver(struct host1x *host1x,
398 struct host1x_driver *driver)
399{
400 struct host1x_device *device;
401 int err;
402
403 mutex_lock(&host1x->devices_lock);
404
405 list_for_each_entry(device, &host1x->devices, list) {
406 if (device->driver == driver) {
407 mutex_unlock(&host1x->devices_lock);
408 return;
409 }
410 }
411
412 mutex_unlock(&host1x->devices_lock);
413
414 err = host1x_device_add(host1x, driver);
415 if (err < 0)
416 dev_err(host1x->dev, "failed to allocate device: %d\n", err);
417}
418
419static void host1x_detach_driver(struct host1x *host1x,
420 struct host1x_driver *driver)
421{
422 struct host1x_device *device, *tmp;
423
424 mutex_lock(&host1x->devices_lock);
425
426 list_for_each_entry_safe(device, tmp, &host1x->devices, list)
427 if (device->driver == driver)
428 host1x_device_del(host1x, device);
429
430 mutex_unlock(&host1x->devices_lock);
431}
432
433int host1x_register(struct host1x *host1x)
434{
435 struct host1x_driver *driver;
436
437 mutex_lock(&devices_lock);
438 list_add_tail(&host1x->list, &devices);
439 mutex_unlock(&devices_lock);
440
441 mutex_lock(&drivers_lock);
442
443 list_for_each_entry(driver, &drivers, list)
444 host1x_attach_driver(host1x, driver);
445
446 mutex_unlock(&drivers_lock);
447
448 return 0;
449}
450
451int host1x_unregister(struct host1x *host1x)
452{
453 struct host1x_driver *driver;
454
455 mutex_lock(&drivers_lock);
456
457 list_for_each_entry(driver, &drivers, list)
458 host1x_detach_driver(host1x, driver);
459
460 mutex_unlock(&drivers_lock);
461
462 mutex_lock(&devices_lock);
463 list_del_init(&host1x->list);
464 mutex_unlock(&devices_lock);
465
466 return 0;
467}
468
469int host1x_driver_register(struct host1x_driver *driver)
470{
471 struct host1x *host1x;
472
473 INIT_LIST_HEAD(&driver->list);
474
475 mutex_lock(&drivers_lock);
476 list_add_tail(&driver->list, &drivers);
477 mutex_unlock(&drivers_lock);
478
479 mutex_lock(&devices_lock);
480
481 list_for_each_entry(host1x, &devices, list)
482 host1x_attach_driver(host1x, driver);
483
484 mutex_unlock(&devices_lock);
485
486 return 0;
487}
488EXPORT_SYMBOL(host1x_driver_register);
489
490void host1x_driver_unregister(struct host1x_driver *driver)
491{
492 mutex_lock(&drivers_lock);
493 list_del_init(&driver->list);
494 mutex_unlock(&drivers_lock);
495}
496EXPORT_SYMBOL(host1x_driver_unregister);
497
498int host1x_client_register(struct host1x_client *client)
499{
500 struct host1x *host1x;
501 int err;
502
503 mutex_lock(&devices_lock);
504
505 list_for_each_entry(host1x, &devices, list) {
506 err = host1x_register_client(host1x, client);
507 if (!err) {
508 mutex_unlock(&devices_lock);
509 return 0;
510 }
511 }
512
513 mutex_unlock(&devices_lock);
514
515 mutex_lock(&clients_lock);
516 list_add_tail(&client->list, &clients);
517 mutex_unlock(&clients_lock);
518
519 return 0;
520}
521EXPORT_SYMBOL(host1x_client_register);
522
523int host1x_client_unregister(struct host1x_client *client)
524{
525 struct host1x_client *c;
526 struct host1x *host1x;
527 int err;
528
529 mutex_lock(&devices_lock);
530
531 list_for_each_entry(host1x, &devices, list) {
532 err = host1x_unregister_client(host1x, client);
533 if (!err) {
534 mutex_unlock(&devices_lock);
535 return 0;
536 }
537 }
538
539 mutex_unlock(&devices_lock);
540 mutex_lock(&clients_lock);
541
542 list_for_each_entry(c, &clients, list) {
543 if (c == client) {
544 list_del_init(&c->list);
545 break;
546 }
547 }
548
549 mutex_unlock(&clients_lock);
550
551 return 0;
552}
553EXPORT_SYMBOL(host1x_client_unregister);