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 
18 static DEFINE_MUTEX(clients_lock);
19 static LIST_HEAD(clients);
20 
21 static DEFINE_MUTEX(drivers_lock);
22 static LIST_HEAD(drivers);
23 
24 static DEFINE_MUTEX(devices_lock);
25 static LIST_HEAD(devices);
26 
27 struct 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  */
host1x_subdev_add(struct host1x_device * device,struct host1x_driver * driver,struct device_node * np)39 static 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  */
host1x_subdev_del(struct host1x_subdev * subdev)78 static 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  */
host1x_device_parse_dt(struct host1x_device * device,struct host1x_driver * driver)90 static 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 
host1x_subdev_register(struct host1x_device * device,struct host1x_subdev * subdev,struct host1x_client * client)110 static 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 
__host1x_subdev_unregister(struct host1x_device * device,struct host1x_subdev * subdev)139 static 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 
host1x_subdev_unregister(struct host1x_device * device,struct host1x_subdev * subdev)175 static 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  */
host1x_device_init(struct host1x_device * device)193 int 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 
227 teardown:
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 
235 teardown_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 }
243 EXPORT_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  */
host1x_device_exit(struct host1x_device * device)254 int 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 }
290 EXPORT_SYMBOL(host1x_device_exit);
291 
host1x_add_client(struct host1x * host1x,struct host1x_client * client)292 static 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 
host1x_del_client(struct host1x * host1x,struct host1x_client * client)314 static 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 
host1x_device_match(struct device * dev,struct device_driver * drv)336 static int host1x_device_match(struct device *dev, struct device_driver *drv)
337 {
338 	return strcmp(dev_name(dev), drv->name) == 0;
339 }
340 
host1x_device_uevent(struct device * dev,struct kobj_uevent_env * env)341 static 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 
host1x_dma_configure(struct device * dev)371 static int host1x_dma_configure(struct device *dev)
372 {
373 	return of_dma_configure(dev, dev->of_node, true);
374 }
375 
376 static 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 
385 struct 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 
__host1x_device_del(struct host1x_device * device)393 static 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 
host1x_device_release(struct device * dev)441 static 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 
host1x_device_add(struct host1x * host1x,struct host1x_driver * driver)449 static 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  */
host1x_device_del(struct host1x * host1x,struct host1x_device * device)513 static 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 
host1x_attach_driver(struct host1x * host1x,struct host1x_driver * driver)524 static 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 
host1x_detach_driver(struct host1x * host1x,struct host1x_driver * driver)546 static 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 
host1x_devices_show(struct seq_file * s,void * data)560 static 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 }
588 DEFINE_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  */
host1x_register(struct host1x * host1x)598 int 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  */
host1x_unregister(struct host1x * host1x)626 int 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 
host1x_device_probe(struct device * dev)644 static 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 
host1x_device_remove(struct device * dev)655 static 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 
host1x_device_shutdown(struct device * dev)666 static 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  */
host1x_driver_register_full(struct host1x_driver * driver,struct module * owner)685 int 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 }
711 EXPORT_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  */
host1x_driver_unregister(struct host1x_driver * driver)720 void 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 }
737 EXPORT_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  */
__host1x_client_init(struct host1x_client * client,struct lock_class_key * key)744 void __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 }
751 EXPORT_SYMBOL(__host1x_client_init);
752 
753 /**
754  * host1x_client_exit() - uninitialize a host1x client
755  * @client: host1x client
756  */
host1x_client_exit(struct host1x_client * client)757 void host1x_client_exit(struct host1x_client *client)
758 {
759 	mutex_destroy(&client->lock);
760 }
761 EXPORT_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  */
__host1x_client_register(struct host1x_client * client)774 int __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 }
797 EXPORT_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  */
host1x_client_unregister(struct host1x_client * client)806 int 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 }
838 EXPORT_SYMBOL(host1x_client_unregister);
839 
host1x_client_suspend(struct host1x_client * client)840 int 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 
865 resume:
866 	if (client->usecount == 0)
867 		if (client->ops && client->ops->resume)
868 			client->ops->resume(client);
869 
870 	client->usecount++;
871 unlock:
872 	mutex_unlock(&client->lock);
873 	return err;
874 }
875 EXPORT_SYMBOL(host1x_client_suspend);
876 
host1x_client_resume(struct host1x_client * client)877 int 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 
902 suspend:
903 	if (client->parent)
904 		host1x_client_suspend(client->parent);
905 unlock:
906 	mutex_unlock(&client->lock);
907 	return err;
908 }
909 EXPORT_SYMBOL(host1x_client_resume);
910 
host1x_bo_pin(struct device * dev,struct host1x_bo * bo,enum dma_data_direction dir,struct host1x_bo_cache * cache)911 struct 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 
946 unlock:
947 	if (cache)
948 		mutex_unlock(&cache->lock);
949 
950 	return mapping;
951 }
952 EXPORT_SYMBOL(host1x_bo_pin);
953 
__host1x_bo_unpin(struct kref * ref)954 static 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 
host1x_bo_unpin(struct host1x_bo_mapping * mapping)972 void 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 }
984 EXPORT_SYMBOL(host1x_bo_unpin);
985