xref: /linux/drivers/phy/phy-core.c (revision d91517839e5d95adc0cf4b28caa7af62a71de526)
1 /*
2  * phy-core.c  --  Generic Phy framework.
3  *
4  * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
5  *
6  * Author: Kishon Vijay Abraham I <kishon@ti.com>
7  *
8  * This program is free software; you can redistribute  it and/or modify it
9  * under  the terms of  the GNU General  Public License as published by the
10  * Free Software Foundation;  either version 2 of the  License, or (at your
11  * option) any later version.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/export.h>
16 #include <linux/module.h>
17 #include <linux/err.h>
18 #include <linux/device.h>
19 #include <linux/slab.h>
20 #include <linux/of.h>
21 #include <linux/phy/phy.h>
22 #include <linux/idr.h>
23 #include <linux/pm_runtime.h>
24 
25 static struct class *phy_class;
26 static DEFINE_MUTEX(phy_provider_mutex);
27 static LIST_HEAD(phy_provider_list);
28 static DEFINE_IDA(phy_ida);
29 
30 static void devm_phy_release(struct device *dev, void *res)
31 {
32 	struct phy *phy = *(struct phy **)res;
33 
34 	phy_put(phy);
35 }
36 
37 static void devm_phy_provider_release(struct device *dev, void *res)
38 {
39 	struct phy_provider *phy_provider = *(struct phy_provider **)res;
40 
41 	of_phy_provider_unregister(phy_provider);
42 }
43 
44 static void devm_phy_consume(struct device *dev, void *res)
45 {
46 	struct phy *phy = *(struct phy **)res;
47 
48 	phy_destroy(phy);
49 }
50 
51 static int devm_phy_match(struct device *dev, void *res, void *match_data)
52 {
53 	return res == match_data;
54 }
55 
56 static struct phy *phy_lookup(struct device *device, const char *port)
57 {
58 	unsigned int count;
59 	struct phy *phy;
60 	struct device *dev;
61 	struct phy_consumer *consumers;
62 	struct class_dev_iter iter;
63 
64 	class_dev_iter_init(&iter, phy_class, NULL, NULL);
65 	while ((dev = class_dev_iter_next(&iter))) {
66 		phy = to_phy(dev);
67 		count = phy->init_data->num_consumers;
68 		consumers = phy->init_data->consumers;
69 		while (count--) {
70 			if (!strcmp(consumers->dev_name, dev_name(device)) &&
71 					!strcmp(consumers->port, port)) {
72 				class_dev_iter_exit(&iter);
73 				return phy;
74 			}
75 			consumers++;
76 		}
77 	}
78 
79 	class_dev_iter_exit(&iter);
80 	return ERR_PTR(-ENODEV);
81 }
82 
83 static struct phy_provider *of_phy_provider_lookup(struct device_node *node)
84 {
85 	struct phy_provider *phy_provider;
86 
87 	list_for_each_entry(phy_provider, &phy_provider_list, list) {
88 		if (phy_provider->dev->of_node == node)
89 			return phy_provider;
90 	}
91 
92 	return ERR_PTR(-EPROBE_DEFER);
93 }
94 
95 int phy_pm_runtime_get(struct phy *phy)
96 {
97 	int ret;
98 
99 	if (!pm_runtime_enabled(&phy->dev))
100 		return -ENOTSUPP;
101 
102 	ret = pm_runtime_get(&phy->dev);
103 	if (ret < 0 && ret != -EINPROGRESS)
104 		pm_runtime_put_noidle(&phy->dev);
105 
106 	return ret;
107 }
108 EXPORT_SYMBOL_GPL(phy_pm_runtime_get);
109 
110 int phy_pm_runtime_get_sync(struct phy *phy)
111 {
112 	int ret;
113 
114 	if (!pm_runtime_enabled(&phy->dev))
115 		return -ENOTSUPP;
116 
117 	ret = pm_runtime_get_sync(&phy->dev);
118 	if (ret < 0)
119 		pm_runtime_put_sync(&phy->dev);
120 
121 	return ret;
122 }
123 EXPORT_SYMBOL_GPL(phy_pm_runtime_get_sync);
124 
125 int phy_pm_runtime_put(struct phy *phy)
126 {
127 	if (!pm_runtime_enabled(&phy->dev))
128 		return -ENOTSUPP;
129 
130 	return pm_runtime_put(&phy->dev);
131 }
132 EXPORT_SYMBOL_GPL(phy_pm_runtime_put);
133 
134 int phy_pm_runtime_put_sync(struct phy *phy)
135 {
136 	if (!pm_runtime_enabled(&phy->dev))
137 		return -ENOTSUPP;
138 
139 	return pm_runtime_put_sync(&phy->dev);
140 }
141 EXPORT_SYMBOL_GPL(phy_pm_runtime_put_sync);
142 
143 void phy_pm_runtime_allow(struct phy *phy)
144 {
145 	if (!pm_runtime_enabled(&phy->dev))
146 		return;
147 
148 	pm_runtime_allow(&phy->dev);
149 }
150 EXPORT_SYMBOL_GPL(phy_pm_runtime_allow);
151 
152 void phy_pm_runtime_forbid(struct phy *phy)
153 {
154 	if (!pm_runtime_enabled(&phy->dev))
155 		return;
156 
157 	pm_runtime_forbid(&phy->dev);
158 }
159 EXPORT_SYMBOL_GPL(phy_pm_runtime_forbid);
160 
161 int phy_init(struct phy *phy)
162 {
163 	int ret;
164 
165 	ret = phy_pm_runtime_get_sync(phy);
166 	if (ret < 0 && ret != -ENOTSUPP)
167 		return ret;
168 
169 	mutex_lock(&phy->mutex);
170 	if (phy->init_count == 0 && phy->ops->init) {
171 		ret = phy->ops->init(phy);
172 		if (ret < 0) {
173 			dev_err(&phy->dev, "phy init failed --> %d\n", ret);
174 			goto out;
175 		}
176 	}
177 	++phy->init_count;
178 
179 out:
180 	mutex_unlock(&phy->mutex);
181 	phy_pm_runtime_put(phy);
182 	return ret;
183 }
184 EXPORT_SYMBOL_GPL(phy_init);
185 
186 int phy_exit(struct phy *phy)
187 {
188 	int ret;
189 
190 	ret = phy_pm_runtime_get_sync(phy);
191 	if (ret < 0 && ret != -ENOTSUPP)
192 		return ret;
193 
194 	mutex_lock(&phy->mutex);
195 	if (phy->init_count == 1 && phy->ops->exit) {
196 		ret = phy->ops->exit(phy);
197 		if (ret < 0) {
198 			dev_err(&phy->dev, "phy exit failed --> %d\n", ret);
199 			goto out;
200 		}
201 	}
202 	--phy->init_count;
203 
204 out:
205 	mutex_unlock(&phy->mutex);
206 	phy_pm_runtime_put(phy);
207 	return ret;
208 }
209 EXPORT_SYMBOL_GPL(phy_exit);
210 
211 int phy_power_on(struct phy *phy)
212 {
213 	int ret;
214 
215 	ret = phy_pm_runtime_get_sync(phy);
216 	if (ret < 0 && ret != -ENOTSUPP)
217 		return ret;
218 
219 	mutex_lock(&phy->mutex);
220 	if (phy->power_count == 0 && phy->ops->power_on) {
221 		ret = phy->ops->power_on(phy);
222 		if (ret < 0) {
223 			dev_err(&phy->dev, "phy poweron failed --> %d\n", ret);
224 			goto out;
225 		}
226 	}
227 	++phy->power_count;
228 	mutex_unlock(&phy->mutex);
229 	return 0;
230 
231 out:
232 	mutex_unlock(&phy->mutex);
233 	phy_pm_runtime_put_sync(phy);
234 
235 	return ret;
236 }
237 EXPORT_SYMBOL_GPL(phy_power_on);
238 
239 int phy_power_off(struct phy *phy)
240 {
241 	int ret;
242 
243 	mutex_lock(&phy->mutex);
244 	if (phy->power_count == 1 && phy->ops->power_off) {
245 		ret =  phy->ops->power_off(phy);
246 		if (ret < 0) {
247 			dev_err(&phy->dev, "phy poweroff failed --> %d\n", ret);
248 			mutex_unlock(&phy->mutex);
249 			return ret;
250 		}
251 	}
252 	--phy->power_count;
253 	mutex_unlock(&phy->mutex);
254 	phy_pm_runtime_put(phy);
255 
256 	return 0;
257 }
258 EXPORT_SYMBOL_GPL(phy_power_off);
259 
260 /**
261  * of_phy_get() - lookup and obtain a reference to a phy by phandle
262  * @dev: device that requests this phy
263  * @index: the index of the phy
264  *
265  * Returns the phy associated with the given phandle value,
266  * after getting a refcount to it or -ENODEV if there is no such phy or
267  * -EPROBE_DEFER if there is a phandle to the phy, but the device is
268  * not yet loaded. This function uses of_xlate call back function provided
269  * while registering the phy_provider to find the phy instance.
270  */
271 static struct phy *of_phy_get(struct device *dev, int index)
272 {
273 	int ret;
274 	struct phy_provider *phy_provider;
275 	struct phy *phy = NULL;
276 	struct of_phandle_args args;
277 
278 	ret = of_parse_phandle_with_args(dev->of_node, "phys", "#phy-cells",
279 		index, &args);
280 	if (ret) {
281 		dev_dbg(dev, "failed to get phy in %s node\n",
282 			dev->of_node->full_name);
283 		return ERR_PTR(-ENODEV);
284 	}
285 
286 	mutex_lock(&phy_provider_mutex);
287 	phy_provider = of_phy_provider_lookup(args.np);
288 	if (IS_ERR(phy_provider) || !try_module_get(phy_provider->owner)) {
289 		phy = ERR_PTR(-EPROBE_DEFER);
290 		goto err0;
291 	}
292 
293 	phy = phy_provider->of_xlate(phy_provider->dev, &args);
294 	module_put(phy_provider->owner);
295 
296 err0:
297 	mutex_unlock(&phy_provider_mutex);
298 	of_node_put(args.np);
299 
300 	return phy;
301 }
302 
303 /**
304  * phy_put() - release the PHY
305  * @phy: the phy returned by phy_get()
306  *
307  * Releases a refcount the caller received from phy_get().
308  */
309 void phy_put(struct phy *phy)
310 {
311 	if (IS_ERR(phy))
312 		return;
313 
314 	module_put(phy->ops->owner);
315 	put_device(&phy->dev);
316 }
317 EXPORT_SYMBOL_GPL(phy_put);
318 
319 /**
320  * devm_phy_put() - release the PHY
321  * @dev: device that wants to release this phy
322  * @phy: the phy returned by devm_phy_get()
323  *
324  * destroys the devres associated with this phy and invokes phy_put
325  * to release the phy.
326  */
327 void devm_phy_put(struct device *dev, struct phy *phy)
328 {
329 	int r;
330 
331 	r = devres_destroy(dev, devm_phy_release, devm_phy_match, phy);
332 	dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
333 }
334 EXPORT_SYMBOL_GPL(devm_phy_put);
335 
336 /**
337  * of_phy_simple_xlate() - returns the phy instance from phy provider
338  * @dev: the PHY provider device
339  * @args: of_phandle_args (not used here)
340  *
341  * Intended to be used by phy provider for the common case where #phy-cells is
342  * 0. For other cases where #phy-cells is greater than '0', the phy provider
343  * should provide a custom of_xlate function that reads the *args* and returns
344  * the appropriate phy.
345  */
346 struct phy *of_phy_simple_xlate(struct device *dev, struct of_phandle_args
347 	*args)
348 {
349 	struct phy *phy;
350 	struct class_dev_iter iter;
351 	struct device_node *node = dev->of_node;
352 
353 	class_dev_iter_init(&iter, phy_class, NULL, NULL);
354 	while ((dev = class_dev_iter_next(&iter))) {
355 		phy = to_phy(dev);
356 		if (node != phy->dev.of_node)
357 			continue;
358 
359 		class_dev_iter_exit(&iter);
360 		return phy;
361 	}
362 
363 	class_dev_iter_exit(&iter);
364 	return ERR_PTR(-ENODEV);
365 }
366 EXPORT_SYMBOL_GPL(of_phy_simple_xlate);
367 
368 /**
369  * phy_get() - lookup and obtain a reference to a phy.
370  * @dev: device that requests this phy
371  * @string: the phy name as given in the dt data or the name of the controller
372  * port for non-dt case
373  *
374  * Returns the phy driver, after getting a refcount to it; or
375  * -ENODEV if there is no such phy.  The caller is responsible for
376  * calling phy_put() to release that count.
377  */
378 struct phy *phy_get(struct device *dev, const char *string)
379 {
380 	int index = 0;
381 	struct phy *phy;
382 
383 	if (string == NULL) {
384 		dev_WARN(dev, "missing string\n");
385 		return ERR_PTR(-EINVAL);
386 	}
387 
388 	if (dev->of_node) {
389 		index = of_property_match_string(dev->of_node, "phy-names",
390 			string);
391 		phy = of_phy_get(dev, index);
392 		if (IS_ERR(phy)) {
393 			dev_err(dev, "unable to find phy\n");
394 			return phy;
395 		}
396 	} else {
397 		phy = phy_lookup(dev, string);
398 		if (IS_ERR(phy)) {
399 			dev_err(dev, "unable to find phy\n");
400 			return phy;
401 		}
402 	}
403 
404 	if (!try_module_get(phy->ops->owner))
405 		return ERR_PTR(-EPROBE_DEFER);
406 
407 	get_device(&phy->dev);
408 
409 	return phy;
410 }
411 EXPORT_SYMBOL_GPL(phy_get);
412 
413 /**
414  * devm_phy_get() - lookup and obtain a reference to a phy.
415  * @dev: device that requests this phy
416  * @string: the phy name as given in the dt data or phy device name
417  * for non-dt case
418  *
419  * Gets the phy using phy_get(), and associates a device with it using
420  * devres. On driver detach, release function is invoked on the devres data,
421  * then, devres data is freed.
422  */
423 struct phy *devm_phy_get(struct device *dev, const char *string)
424 {
425 	struct phy **ptr, *phy;
426 
427 	ptr = devres_alloc(devm_phy_release, sizeof(*ptr), GFP_KERNEL);
428 	if (!ptr)
429 		return ERR_PTR(-ENOMEM);
430 
431 	phy = phy_get(dev, string);
432 	if (!IS_ERR(phy)) {
433 		*ptr = phy;
434 		devres_add(dev, ptr);
435 	} else {
436 		devres_free(ptr);
437 	}
438 
439 	return phy;
440 }
441 EXPORT_SYMBOL_GPL(devm_phy_get);
442 
443 /**
444  * phy_create() - create a new phy
445  * @dev: device that is creating the new phy
446  * @ops: function pointers for performing phy operations
447  * @init_data: contains the list of PHY consumers or NULL
448  *
449  * Called to create a phy using phy framework.
450  */
451 struct phy *phy_create(struct device *dev, const struct phy_ops *ops,
452 	struct phy_init_data *init_data)
453 {
454 	int ret;
455 	int id;
456 	struct phy *phy;
457 
458 	if (WARN_ON(!dev))
459 		return ERR_PTR(-EINVAL);
460 
461 	phy = kzalloc(sizeof(*phy), GFP_KERNEL);
462 	if (!phy)
463 		return ERR_PTR(-ENOMEM);
464 
465 	id = ida_simple_get(&phy_ida, 0, 0, GFP_KERNEL);
466 	if (id < 0) {
467 		dev_err(dev, "unable to get id\n");
468 		ret = id;
469 		goto free_phy;
470 	}
471 
472 	device_initialize(&phy->dev);
473 	mutex_init(&phy->mutex);
474 
475 	phy->dev.class = phy_class;
476 	phy->dev.parent = dev;
477 	phy->dev.of_node = dev->of_node;
478 	phy->id = id;
479 	phy->ops = ops;
480 	phy->init_data = init_data;
481 
482 	ret = dev_set_name(&phy->dev, "phy-%s.%d", dev_name(dev), id);
483 	if (ret)
484 		goto put_dev;
485 
486 	ret = device_add(&phy->dev);
487 	if (ret)
488 		goto put_dev;
489 
490 	if (pm_runtime_enabled(dev)) {
491 		pm_runtime_enable(&phy->dev);
492 		pm_runtime_no_callbacks(&phy->dev);
493 	}
494 
495 	return phy;
496 
497 put_dev:
498 	put_device(&phy->dev);
499 	ida_remove(&phy_ida, phy->id);
500 free_phy:
501 	kfree(phy);
502 	return ERR_PTR(ret);
503 }
504 EXPORT_SYMBOL_GPL(phy_create);
505 
506 /**
507  * devm_phy_create() - create a new phy
508  * @dev: device that is creating the new phy
509  * @ops: function pointers for performing phy operations
510  * @init_data: contains the list of PHY consumers or NULL
511  *
512  * Creates a new PHY device adding it to the PHY class.
513  * While at that, it also associates the device with the phy using devres.
514  * On driver detach, release function is invoked on the devres data,
515  * then, devres data is freed.
516  */
517 struct phy *devm_phy_create(struct device *dev, const struct phy_ops *ops,
518 	struct phy_init_data *init_data)
519 {
520 	struct phy **ptr, *phy;
521 
522 	ptr = devres_alloc(devm_phy_consume, sizeof(*ptr), GFP_KERNEL);
523 	if (!ptr)
524 		return ERR_PTR(-ENOMEM);
525 
526 	phy = phy_create(dev, ops, init_data);
527 	if (!IS_ERR(phy)) {
528 		*ptr = phy;
529 		devres_add(dev, ptr);
530 	} else {
531 		devres_free(ptr);
532 	}
533 
534 	return phy;
535 }
536 EXPORT_SYMBOL_GPL(devm_phy_create);
537 
538 /**
539  * phy_destroy() - destroy the phy
540  * @phy: the phy to be destroyed
541  *
542  * Called to destroy the phy.
543  */
544 void phy_destroy(struct phy *phy)
545 {
546 	pm_runtime_disable(&phy->dev);
547 	device_unregister(&phy->dev);
548 }
549 EXPORT_SYMBOL_GPL(phy_destroy);
550 
551 /**
552  * devm_phy_destroy() - destroy the PHY
553  * @dev: device that wants to release this phy
554  * @phy: the phy returned by devm_phy_get()
555  *
556  * destroys the devres associated with this phy and invokes phy_destroy
557  * to destroy the phy.
558  */
559 void devm_phy_destroy(struct device *dev, struct phy *phy)
560 {
561 	int r;
562 
563 	r = devres_destroy(dev, devm_phy_consume, devm_phy_match, phy);
564 	dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
565 }
566 EXPORT_SYMBOL_GPL(devm_phy_destroy);
567 
568 /**
569  * __of_phy_provider_register() - create/register phy provider with the framework
570  * @dev: struct device of the phy provider
571  * @owner: the module owner containing of_xlate
572  * @of_xlate: function pointer to obtain phy instance from phy provider
573  *
574  * Creates struct phy_provider from dev and of_xlate function pointer.
575  * This is used in the case of dt boot for finding the phy instance from
576  * phy provider.
577  */
578 struct phy_provider *__of_phy_provider_register(struct device *dev,
579 	struct module *owner, struct phy * (*of_xlate)(struct device *dev,
580 	struct of_phandle_args *args))
581 {
582 	struct phy_provider *phy_provider;
583 
584 	phy_provider = kzalloc(sizeof(*phy_provider), GFP_KERNEL);
585 	if (!phy_provider)
586 		return ERR_PTR(-ENOMEM);
587 
588 	phy_provider->dev = dev;
589 	phy_provider->owner = owner;
590 	phy_provider->of_xlate = of_xlate;
591 
592 	mutex_lock(&phy_provider_mutex);
593 	list_add_tail(&phy_provider->list, &phy_provider_list);
594 	mutex_unlock(&phy_provider_mutex);
595 
596 	return phy_provider;
597 }
598 EXPORT_SYMBOL_GPL(__of_phy_provider_register);
599 
600 /**
601  * __devm_of_phy_provider_register() - create/register phy provider with the
602  * framework
603  * @dev: struct device of the phy provider
604  * @owner: the module owner containing of_xlate
605  * @of_xlate: function pointer to obtain phy instance from phy provider
606  *
607  * Creates struct phy_provider from dev and of_xlate function pointer.
608  * This is used in the case of dt boot for finding the phy instance from
609  * phy provider. While at that, it also associates the device with the
610  * phy provider using devres. On driver detach, release function is invoked
611  * on the devres data, then, devres data is freed.
612  */
613 struct phy_provider *__devm_of_phy_provider_register(struct device *dev,
614 	struct module *owner, struct phy * (*of_xlate)(struct device *dev,
615 	struct of_phandle_args *args))
616 {
617 	struct phy_provider **ptr, *phy_provider;
618 
619 	ptr = devres_alloc(devm_phy_provider_release, sizeof(*ptr), GFP_KERNEL);
620 	if (!ptr)
621 		return ERR_PTR(-ENOMEM);
622 
623 	phy_provider = __of_phy_provider_register(dev, owner, of_xlate);
624 	if (!IS_ERR(phy_provider)) {
625 		*ptr = phy_provider;
626 		devres_add(dev, ptr);
627 	} else {
628 		devres_free(ptr);
629 	}
630 
631 	return phy_provider;
632 }
633 EXPORT_SYMBOL_GPL(__devm_of_phy_provider_register);
634 
635 /**
636  * of_phy_provider_unregister() - unregister phy provider from the framework
637  * @phy_provider: phy provider returned by of_phy_provider_register()
638  *
639  * Removes the phy_provider created using of_phy_provider_register().
640  */
641 void of_phy_provider_unregister(struct phy_provider *phy_provider)
642 {
643 	if (IS_ERR(phy_provider))
644 		return;
645 
646 	mutex_lock(&phy_provider_mutex);
647 	list_del(&phy_provider->list);
648 	kfree(phy_provider);
649 	mutex_unlock(&phy_provider_mutex);
650 }
651 EXPORT_SYMBOL_GPL(of_phy_provider_unregister);
652 
653 /**
654  * devm_of_phy_provider_unregister() - remove phy provider from the framework
655  * @dev: struct device of the phy provider
656  *
657  * destroys the devres associated with this phy provider and invokes
658  * of_phy_provider_unregister to unregister the phy provider.
659  */
660 void devm_of_phy_provider_unregister(struct device *dev,
661 	struct phy_provider *phy_provider) {
662 	int r;
663 
664 	r = devres_destroy(dev, devm_phy_provider_release, devm_phy_match,
665 		phy_provider);
666 	dev_WARN_ONCE(dev, r, "couldn't find PHY provider device resource\n");
667 }
668 EXPORT_SYMBOL_GPL(devm_of_phy_provider_unregister);
669 
670 /**
671  * phy_release() - release the phy
672  * @dev: the dev member within phy
673  *
674  * When the last reference to the device is removed, it is called
675  * from the embedded kobject as release method.
676  */
677 static void phy_release(struct device *dev)
678 {
679 	struct phy *phy;
680 
681 	phy = to_phy(dev);
682 	dev_vdbg(dev, "releasing '%s'\n", dev_name(dev));
683 	ida_remove(&phy_ida, phy->id);
684 	kfree(phy);
685 }
686 
687 static int __init phy_core_init(void)
688 {
689 	phy_class = class_create(THIS_MODULE, "phy");
690 	if (IS_ERR(phy_class)) {
691 		pr_err("failed to create phy class --> %ld\n",
692 			PTR_ERR(phy_class));
693 		return PTR_ERR(phy_class);
694 	}
695 
696 	phy_class->dev_release = phy_release;
697 
698 	return 0;
699 }
700 module_init(phy_core_init);
701 
702 static void __exit phy_core_exit(void)
703 {
704 	class_destroy(phy_class);
705 }
706 module_exit(phy_core_exit);
707 
708 MODULE_DESCRIPTION("Generic PHY Framework");
709 MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
710 MODULE_LICENSE("GPL v2");
711