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v5.9
  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);
v6.2
  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/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 node
 35 * @device: host1x device to add the subdevice to
 36 * @driver: host1x driver containing the subdevices
 37 * @np: device node
 38 */
 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 subdevice
 76 * @subdev: subdevice to remove
 77 */
 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 subdevices
 87 * @device: host1x logical device
 88 * @driver: host1x driver
 89 */
 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) subdevices
118	 * and associate it with a client. At the same time, associate the
119	 * 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		else
135			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 the
146	 * 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 remove
157	 * 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 it
165	 * when the device is about to be deleted.
166	 *
167	 * This is somewhat complicated by the fact that this function is
168	 * used to remove the subdevice when a client is unregistered but
169	 * 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 device
185 * @device: host1x logical device
186 *
187 * The driver for the host1x logical device can call this during execution of
188 * its &host1x_driver.probe implementation to initialize each of its clients.
189 * The client drivers access the subsystem specific driver data using the
190 * &host1x_client.parent field and driver data associated with it (usually by
191 * 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 device
247 * @device: host1x logical device
248 *
249 * When the driver for a host1x logical device is unloaded, it can call this
250 * function to tear down each of its clients. Typically this is done after a
251 * subsystem-specific data structure is removed and the functionality can no
252 * 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, struct device_driver *drv)
337{
338	return strcmp(dev_name(dev), drv->name) == 0;
339}
340
341static int host1x_device_uevent(struct device *dev,
342				struct kobj_uevent_env *env)
343{
344	struct device_node *np = dev->parent->of_node;
345	unsigned int count = 0;
346	struct property *p;
347	const char *compat;
348
349	/*
350	 * This duplicates most of of_device_uevent(), but the latter cannot
351	 * be called from modules and operates on dev->of_node, which is not
352	 * available in this case.
353	 *
354	 * Note that this is really only needed for backwards compatibility
355	 * with libdrm, which parses this information from sysfs and will
356	 * fail if it can't find the OF_FULLNAME, specifically.
357	 */
358	add_uevent_var(env, "OF_NAME=%pOFn", np);
359	add_uevent_var(env, "OF_FULLNAME=%pOF", np);
360
361	of_property_for_each_string(np, "compatible", p, compat) {
362		add_uevent_var(env, "OF_COMPATIBLE_%u=%s", count, compat);
363		count++;
364	}
365
366	add_uevent_var(env, "OF_COMPATIBLE_N=%u", count);
367
368	return 0;
369}
370
371static int host1x_dma_configure(struct device *dev)
372{
373	return of_dma_configure(dev, dev->of_node, true);
374}
375
376static const struct dev_pm_ops host1x_device_pm_ops = {
377	.suspend = pm_generic_suspend,
378	.resume = pm_generic_resume,
379	.freeze = pm_generic_freeze,
380	.thaw = pm_generic_thaw,
381	.poweroff = pm_generic_poweroff,
382	.restore = pm_generic_restore,
383};
384
385struct bus_type host1x_bus_type = {
386	.name = "host1x",
387	.match = host1x_device_match,
388	.uevent = host1x_device_uevent,
389	.dma_configure = host1x_dma_configure,
390	.pm = &host1x_device_pm_ops,
391};
392
393static void __host1x_device_del(struct host1x_device *device)
394{
395	struct host1x_subdev *subdev, *sd;
396	struct host1x_client *client, *cl;
397
398	mutex_lock(&device->subdevs_lock);
399
400	/* unregister subdevices */
401	list_for_each_entry_safe(subdev, sd, &device->active, list) {
402		/*
403		 * host1x_subdev_unregister() will remove the client from
404		 * any lists, so we'll need to manually add it back to the
405		 * list of idle clients.
406		 *
407		 * XXX: Alternatively, perhaps don't remove the client from
408		 * any lists in host1x_subdev_unregister() and instead do
409		 * that explicitly from host1x_unregister_client()?
410		 */
411		client = subdev->client;
412
413		__host1x_subdev_unregister(device, subdev);
414
415		/* add the client to the list of idle clients */
416		mutex_lock(&clients_lock);
417		list_add_tail(&client->list, &clients);
418		mutex_unlock(&clients_lock);
419	}
420
421	/* remove subdevices */
422	list_for_each_entry_safe(subdev, sd, &device->subdevs, list)
423		host1x_subdev_del(subdev);
424
425	mutex_unlock(&device->subdevs_lock);
426
427	/* move clients to idle list */
428	mutex_lock(&clients_lock);
429	mutex_lock(&device->clients_lock);
430
431	list_for_each_entry_safe(client, cl, &device->clients, list)
432		list_move_tail(&client->list, &clients);
433
434	mutex_unlock(&device->clients_lock);
435	mutex_unlock(&clients_lock);
436
437	/* finally remove the device */
438	list_del_init(&device->list);
439}
440
441static void host1x_device_release(struct device *dev)
442{
443	struct host1x_device *device = to_host1x_device(dev);
444
445	__host1x_device_del(device);
446	kfree(device);
447}
448
449static int host1x_device_add(struct host1x *host1x,
450			     struct host1x_driver *driver)
451{
452	struct host1x_client *client, *tmp;
453	struct host1x_subdev *subdev;
454	struct host1x_device *device;
455	int err;
456
457	device = kzalloc(sizeof(*device), GFP_KERNEL);
458	if (!device)
459		return -ENOMEM;
460
461	device_initialize(&device->dev);
462
463	mutex_init(&device->subdevs_lock);
464	INIT_LIST_HEAD(&device->subdevs);
465	INIT_LIST_HEAD(&device->active);
466	mutex_init(&device->clients_lock);
467	INIT_LIST_HEAD(&device->clients);
468	INIT_LIST_HEAD(&device->list);
469	device->driver = driver;
470
471	device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask;
472	device->dev.dma_mask = &device->dev.coherent_dma_mask;
473	dev_set_name(&device->dev, "%s", driver->driver.name);
474	device->dev.release = host1x_device_release;
475	device->dev.bus = &host1x_bus_type;
476	device->dev.parent = host1x->dev;
477
478	of_dma_configure(&device->dev, host1x->dev->of_node, true);
479
480	device->dev.dma_parms = &device->dma_parms;
481	dma_set_max_seg_size(&device->dev, UINT_MAX);
482
483	err = host1x_device_parse_dt(device, driver);
484	if (err < 0) {
485		kfree(device);
486		return err;
487	}
488
489	list_add_tail(&device->list, &host1x->devices);
490
491	mutex_lock(&clients_lock);
492
493	list_for_each_entry_safe(client, tmp, &clients, list) {
494		list_for_each_entry(subdev, &device->subdevs, list) {
495			if (subdev->np == client->dev->of_node) {
496				host1x_subdev_register(device, subdev, client);
497				break;
498			}
499		}
500	}
501
502	mutex_unlock(&clients_lock);
503
504	return 0;
505}
506
507/*
508 * Removes a device by first unregistering any subdevices and then removing
509 * itself from the list of devices.
510 *
511 * This function must be called with the host1x->devices_lock held.
512 */
513static void host1x_device_del(struct host1x *host1x,
514			      struct host1x_device *device)
515{
516	if (device->registered) {
517		device->registered = false;
518		device_del(&device->dev);
519	}
520
521	put_device(&device->dev);
522}
523
524static void host1x_attach_driver(struct host1x *host1x,
525				 struct host1x_driver *driver)
526{
527	struct host1x_device *device;
528	int err;
529
530	mutex_lock(&host1x->devices_lock);
531
532	list_for_each_entry(device, &host1x->devices, list) {
533		if (device->driver == driver) {
534			mutex_unlock(&host1x->devices_lock);
535			return;
536		}
537	}
538
539	err = host1x_device_add(host1x, driver);
540	if (err < 0)
541		dev_err(host1x->dev, "failed to allocate device: %d\n", err);
542
543	mutex_unlock(&host1x->devices_lock);
544}
545
546static void host1x_detach_driver(struct host1x *host1x,
547				 struct host1x_driver *driver)
548{
549	struct host1x_device *device, *tmp;
550
551	mutex_lock(&host1x->devices_lock);
552
553	list_for_each_entry_safe(device, tmp, &host1x->devices, list)
554		if (device->driver == driver)
555			host1x_device_del(host1x, device);
556
557	mutex_unlock(&host1x->devices_lock);
558}
559
560static int host1x_devices_show(struct seq_file *s, void *data)
561{
562	struct host1x *host1x = s->private;
563	struct host1x_device *device;
564
565	mutex_lock(&host1x->devices_lock);
566
567	list_for_each_entry(device, &host1x->devices, list) {
568		struct host1x_subdev *subdev;
569
570		seq_printf(s, "%s\n", dev_name(&device->dev));
571
572		mutex_lock(&device->subdevs_lock);
573
574		list_for_each_entry(subdev, &device->active, list)
575			seq_printf(s, "  %pOFf: %s\n", subdev->np,
576				   dev_name(subdev->client->dev));
577
578		list_for_each_entry(subdev, &device->subdevs, list)
579			seq_printf(s, "  %pOFf:\n", subdev->np);
580
581		mutex_unlock(&device->subdevs_lock);
582	}
583
584	mutex_unlock(&host1x->devices_lock);
585
586	return 0;
587}
588DEFINE_SHOW_ATTRIBUTE(host1x_devices);
589
590/**
591 * host1x_register() - register a host1x controller
592 * @host1x: host1x controller
593 *
594 * The host1x controller driver uses this to register a host1x controller with
595 * the infrastructure. Note that all Tegra SoC generations have only ever come
596 * with a single host1x instance, so this function is somewhat academic.
597 */
598int host1x_register(struct host1x *host1x)
599{
600	struct host1x_driver *driver;
601
602	mutex_lock(&devices_lock);
603	list_add_tail(&host1x->list, &devices);
604	mutex_unlock(&devices_lock);
605
606	mutex_lock(&drivers_lock);
607
608	list_for_each_entry(driver, &drivers, list)
609		host1x_attach_driver(host1x, driver);
610
611	mutex_unlock(&drivers_lock);
612
613	debugfs_create_file("devices", S_IRUGO, host1x->debugfs, host1x,
614			    &host1x_devices_fops);
615
616	return 0;
617}
618
619/**
620 * host1x_unregister() - unregister a host1x controller
621 * @host1x: host1x controller
622 *
623 * The host1x controller driver uses this to remove a host1x controller from
624 * the infrastructure.
625 */
626int host1x_unregister(struct host1x *host1x)
627{
628	struct host1x_driver *driver;
629
630	mutex_lock(&drivers_lock);
631
632	list_for_each_entry(driver, &drivers, list)
633		host1x_detach_driver(host1x, driver);
634
635	mutex_unlock(&drivers_lock);
636
637	mutex_lock(&devices_lock);
638	list_del_init(&host1x->list);
639	mutex_unlock(&devices_lock);
640
641	return 0;
642}
643
644static int host1x_device_probe(struct device *dev)
645{
646	struct host1x_driver *driver = to_host1x_driver(dev->driver);
647	struct host1x_device *device = to_host1x_device(dev);
648
649	if (driver->probe)
650		return driver->probe(device);
651
652	return 0;
653}
654
655static int host1x_device_remove(struct device *dev)
656{
657	struct host1x_driver *driver = to_host1x_driver(dev->driver);
658	struct host1x_device *device = to_host1x_device(dev);
659
660	if (driver->remove)
661		return driver->remove(device);
662
663	return 0;
664}
665
666static void host1x_device_shutdown(struct device *dev)
667{
668	struct host1x_driver *driver = to_host1x_driver(dev->driver);
669	struct host1x_device *device = to_host1x_device(dev);
670
671	if (driver->shutdown)
672		driver->shutdown(device);
673}
674
675/**
676 * host1x_driver_register_full() - register a host1x driver
677 * @driver: host1x driver
678 * @owner: owner module
679 *
680 * Drivers for host1x logical devices call this function to register a driver
681 * with the infrastructure. Note that since these drive logical devices, the
682 * registration of the driver actually triggers tho logical device creation.
683 * A logical device will be created for each host1x instance.
684 */
685int host1x_driver_register_full(struct host1x_driver *driver,
686				struct module *owner)
687{
688	struct host1x *host1x;
689
690	INIT_LIST_HEAD(&driver->list);
691
692	mutex_lock(&drivers_lock);
693	list_add_tail(&driver->list, &drivers);
694	mutex_unlock(&drivers_lock);
695
696	mutex_lock(&devices_lock);
697
698	list_for_each_entry(host1x, &devices, list)
699		host1x_attach_driver(host1x, driver);
700
701	mutex_unlock(&devices_lock);
702
703	driver->driver.bus = &host1x_bus_type;
704	driver->driver.owner = owner;
705	driver->driver.probe = host1x_device_probe;
706	driver->driver.remove = host1x_device_remove;
707	driver->driver.shutdown = host1x_device_shutdown;
708
709	return driver_register(&driver->driver);
710}
711EXPORT_SYMBOL(host1x_driver_register_full);
712
713/**
714 * host1x_driver_unregister() - unregister a host1x driver
715 * @driver: host1x driver
716 *
717 * Unbinds the driver from each of the host1x logical devices that it is
718 * bound to, effectively removing the subsystem devices that they represent.
719 */
720void host1x_driver_unregister(struct host1x_driver *driver)
721{
722	struct host1x *host1x;
723
724	driver_unregister(&driver->driver);
725
726	mutex_lock(&devices_lock);
727
728	list_for_each_entry(host1x, &devices, list)
729		host1x_detach_driver(host1x, driver);
730
731	mutex_unlock(&devices_lock);
732
733	mutex_lock(&drivers_lock);
734	list_del_init(&driver->list);
735	mutex_unlock(&drivers_lock);
736}
737EXPORT_SYMBOL(host1x_driver_unregister);
738
739/**
740 * __host1x_client_init() - initialize a host1x client
741 * @client: host1x client
742 * @key: lock class key for the client-specific mutex
743 */
744void __host1x_client_init(struct host1x_client *client, struct lock_class_key *key)
745{
746	host1x_bo_cache_init(&client->cache);
747	INIT_LIST_HEAD(&client->list);
748	__mutex_init(&client->lock, "host1x client lock", key);
749	client->usecount = 0;
750}
751EXPORT_SYMBOL(__host1x_client_init);
752
753/**
754 * host1x_client_exit() - uninitialize a host1x client
755 * @client: host1x client
756 */
757void host1x_client_exit(struct host1x_client *client)
758{
759	mutex_destroy(&client->lock);
760}
761EXPORT_SYMBOL(host1x_client_exit);
762
763/**
764 * __host1x_client_register() - register a host1x client
765 * @client: host1x client
766 *
767 * Registers a host1x client with each host1x controller instance. Note that
768 * each client will only match their parent host1x controller and will only be
769 * associated with that instance. Once all clients have been registered with
770 * their parent host1x controller, the infrastructure will set up the logical
771 * device and call host1x_device_init(), which will in turn call each client's
772 * &host1x_client_ops.init implementation.
773 */
774int __host1x_client_register(struct host1x_client *client)
775{
776	struct host1x *host1x;
777	int err;
778
 
 
 
 
779	mutex_lock(&devices_lock);
780
781	list_for_each_entry(host1x, &devices, list) {
782		err = host1x_add_client(host1x, client);
783		if (!err) {
784			mutex_unlock(&devices_lock);
785			return 0;
786		}
787	}
788
789	mutex_unlock(&devices_lock);
790
791	mutex_lock(&clients_lock);
792	list_add_tail(&client->list, &clients);
793	mutex_unlock(&clients_lock);
794
795	return 0;
796}
797EXPORT_SYMBOL(__host1x_client_register);
798
799/**
800 * host1x_client_unregister() - unregister a host1x client
801 * @client: host1x client
802 *
803 * Removes a host1x client from its host1x controller instance. If a logical
804 * device has already been initialized, it will be torn down.
805 */
806int host1x_client_unregister(struct host1x_client *client)
807{
808	struct host1x_client *c;
809	struct host1x *host1x;
810	int err;
811
812	mutex_lock(&devices_lock);
813
814	list_for_each_entry(host1x, &devices, list) {
815		err = host1x_del_client(host1x, client);
816		if (!err) {
817			mutex_unlock(&devices_lock);
818			return 0;
819		}
820	}
821
822	mutex_unlock(&devices_lock);
823	mutex_lock(&clients_lock);
824
825	list_for_each_entry(c, &clients, list) {
826		if (c == client) {
827			list_del_init(&c->list);
828			break;
829		}
830	}
831
832	mutex_unlock(&clients_lock);
833
834	host1x_bo_cache_destroy(&client->cache);
835
836	return 0;
837}
838EXPORT_SYMBOL(host1x_client_unregister);
839
840int host1x_client_suspend(struct host1x_client *client)
841{
842	int err = 0;
843
844	mutex_lock(&client->lock);
845
846	if (client->usecount == 1) {
847		if (client->ops && client->ops->suspend) {
848			err = client->ops->suspend(client);
849			if (err < 0)
850				goto unlock;
851		}
852	}
853
854	client->usecount--;
855	dev_dbg(client->dev, "use count: %u\n", client->usecount);
856
857	if (client->parent) {
858		err = host1x_client_suspend(client->parent);
859		if (err < 0)
860			goto resume;
861	}
862
863	goto unlock;
864
865resume:
866	if (client->usecount == 0)
867		if (client->ops && client->ops->resume)
868			client->ops->resume(client);
869
870	client->usecount++;
871unlock:
872	mutex_unlock(&client->lock);
873	return err;
874}
875EXPORT_SYMBOL(host1x_client_suspend);
876
877int host1x_client_resume(struct host1x_client *client)
878{
879	int err = 0;
880
881	mutex_lock(&client->lock);
882
883	if (client->parent) {
884		err = host1x_client_resume(client->parent);
885		if (err < 0)
886			goto unlock;
887	}
888
889	if (client->usecount == 0) {
890		if (client->ops && client->ops->resume) {
891			err = client->ops->resume(client);
892			if (err < 0)
893				goto suspend;
894		}
895	}
896
897	client->usecount++;
898	dev_dbg(client->dev, "use count: %u\n", client->usecount);
899
900	goto unlock;
901
902suspend:
903	if (client->parent)
904		host1x_client_suspend(client->parent);
905unlock:
906	mutex_unlock(&client->lock);
907	return err;
908}
909EXPORT_SYMBOL(host1x_client_resume);
910
911struct host1x_bo_mapping *host1x_bo_pin(struct device *dev, struct host1x_bo *bo,
912					enum dma_data_direction dir,
913					struct host1x_bo_cache *cache)
914{
915	struct host1x_bo_mapping *mapping;
916
917	if (cache) {
918		mutex_lock(&cache->lock);
919
920		list_for_each_entry(mapping, &cache->mappings, entry) {
921			if (mapping->bo == bo && mapping->direction == dir) {
922				kref_get(&mapping->ref);
923				goto unlock;
924			}
925		}
926	}
927
928	mapping = bo->ops->pin(dev, bo, dir);
929	if (IS_ERR(mapping))
930		goto unlock;
931
932	spin_lock(&mapping->bo->lock);
933	list_add_tail(&mapping->list, &bo->mappings);
934	spin_unlock(&mapping->bo->lock);
935
936	if (cache) {
937		INIT_LIST_HEAD(&mapping->entry);
938		mapping->cache = cache;
939
940		list_add_tail(&mapping->entry, &cache->mappings);
941
942		/* bump reference count to track the copy in the cache */
943		kref_get(&mapping->ref);
944	}
945
946unlock:
947	if (cache)
948		mutex_unlock(&cache->lock);
949
950	return mapping;
951}
952EXPORT_SYMBOL(host1x_bo_pin);
953
954static void __host1x_bo_unpin(struct kref *ref)
955{
956	struct host1x_bo_mapping *mapping = to_host1x_bo_mapping(ref);
957
958	/*
959	 * When the last reference of the mapping goes away, make sure to remove the mapping from
960	 * the cache.
961	 */
962	if (mapping->cache)
963		list_del(&mapping->entry);
964
965	spin_lock(&mapping->bo->lock);
966	list_del(&mapping->list);
967	spin_unlock(&mapping->bo->lock);
968
969	mapping->bo->ops->unpin(mapping);
970}
971
972void host1x_bo_unpin(struct host1x_bo_mapping *mapping)
973{
974	struct host1x_bo_cache *cache = mapping->cache;
975
976	if (cache)
977		mutex_lock(&cache->lock);
978
979	kref_put(&mapping->ref, __host1x_bo_unpin);
980
981	if (cache)
982		mutex_unlock(&cache->lock);
983}
984EXPORT_SYMBOL(host1x_bo_unpin);