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  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * phy.c -- USB phy handling
  4 *
  5 * Copyright (C) 2004-2013 Texas Instruments
  6 */
  7#include <linux/kernel.h>
  8#include <linux/export.h>
  9#include <linux/err.h>
 10#include <linux/device.h>
 11#include <linux/module.h>
 12#include <linux/slab.h>
 13#include <linux/of.h>
 14
 15#include <linux/usb/phy.h>
 16
 17/* Default current range by charger type. */
 18#define DEFAULT_SDP_CUR_MIN	2
 19#define DEFAULT_SDP_CUR_MAX	500
 20#define DEFAULT_SDP_CUR_MIN_SS	150
 21#define DEFAULT_SDP_CUR_MAX_SS	900
 22#define DEFAULT_DCP_CUR_MIN	500
 23#define DEFAULT_DCP_CUR_MAX	5000
 24#define DEFAULT_CDP_CUR_MIN	1500
 25#define DEFAULT_CDP_CUR_MAX	5000
 26#define DEFAULT_ACA_CUR_MIN	1500
 27#define DEFAULT_ACA_CUR_MAX	5000
 28
 29static LIST_HEAD(phy_list);
 30static DEFINE_SPINLOCK(phy_lock);
 31
 32struct phy_devm {
 33	struct usb_phy *phy;
 34	struct notifier_block *nb;
 35};
 36
 37static const char *const usb_chger_type[] = {
 38	[UNKNOWN_TYPE]			= "USB_CHARGER_UNKNOWN_TYPE",
 39	[SDP_TYPE]			= "USB_CHARGER_SDP_TYPE",
 40	[CDP_TYPE]			= "USB_CHARGER_CDP_TYPE",
 41	[DCP_TYPE]			= "USB_CHARGER_DCP_TYPE",
 42	[ACA_TYPE]			= "USB_CHARGER_ACA_TYPE",
 43};
 44
 45static struct usb_phy *__usb_find_phy(struct list_head *list,
 46	enum usb_phy_type type)
 47{
 48	struct usb_phy  *phy = NULL;
 49
 50	list_for_each_entry(phy, list, head) {
 51		if (phy->type != type)
 52			continue;
 53
 54		return phy;
 55	}
 56
 57	return ERR_PTR(-ENODEV);
 58}
 59
 60static struct usb_phy *__of_usb_find_phy(struct device_node *node)
 61{
 62	struct usb_phy  *phy;
 63
 64	if (!of_device_is_available(node))
 65		return ERR_PTR(-ENODEV);
 66
 67	list_for_each_entry(phy, &phy_list, head) {
 68		if (node != phy->dev->of_node)
 69			continue;
 70
 71		return phy;
 72	}
 73
 74	return ERR_PTR(-EPROBE_DEFER);
 75}
 76
 77static void usb_phy_set_default_current(struct usb_phy *usb_phy)
 78{
 79	usb_phy->chg_cur.sdp_min = DEFAULT_SDP_CUR_MIN;
 80	usb_phy->chg_cur.sdp_max = DEFAULT_SDP_CUR_MAX;
 81	usb_phy->chg_cur.dcp_min = DEFAULT_DCP_CUR_MIN;
 82	usb_phy->chg_cur.dcp_max = DEFAULT_DCP_CUR_MAX;
 83	usb_phy->chg_cur.cdp_min = DEFAULT_CDP_CUR_MIN;
 84	usb_phy->chg_cur.cdp_max = DEFAULT_CDP_CUR_MAX;
 85	usb_phy->chg_cur.aca_min = DEFAULT_ACA_CUR_MIN;
 86	usb_phy->chg_cur.aca_max = DEFAULT_ACA_CUR_MAX;
 87}
 88
 89/**
 90 * usb_phy_notify_charger_work - notify the USB charger state
 91 * @work: the charger work to notify the USB charger state
 92 *
 93 * This work can be issued when USB charger state has been changed or
 94 * USB charger current has been changed, then we can notify the current
 95 * what can be drawn to power user and the charger state to userspace.
 96 *
 97 * If we get the charger type from extcon subsystem, we can notify the
 98 * charger state to power user automatically by usb_phy_get_charger_type()
 99 * issuing from extcon subsystem.
100 *
101 * If we get the charger type from ->charger_detect() instead of extcon
102 * subsystem, the usb phy driver should issue usb_phy_set_charger_state()
103 * to set charger state when the charger state has been changed.
104 */
105static void usb_phy_notify_charger_work(struct work_struct *work)
106{
107	struct usb_phy *usb_phy = container_of(work, struct usb_phy, chg_work);
108	char uchger_state[50] = { 0 };
109	char uchger_type[50] = { 0 };
110	char *envp[] = { uchger_state, uchger_type, NULL };
111	unsigned int min, max;
112
113	switch (usb_phy->chg_state) {
114	case USB_CHARGER_PRESENT:
115		usb_phy_get_charger_current(usb_phy, &min, &max);
116
117		atomic_notifier_call_chain(&usb_phy->notifier, max, usb_phy);
118		snprintf(uchger_state, ARRAY_SIZE(uchger_state),
119			 "USB_CHARGER_STATE=%s", "USB_CHARGER_PRESENT");
120		break;
121	case USB_CHARGER_ABSENT:
122		usb_phy_set_default_current(usb_phy);
123
124		atomic_notifier_call_chain(&usb_phy->notifier, 0, usb_phy);
125		snprintf(uchger_state, ARRAY_SIZE(uchger_state),
126			 "USB_CHARGER_STATE=%s", "USB_CHARGER_ABSENT");
127		break;
128	default:
129		dev_warn(usb_phy->dev, "Unknown USB charger state: %d\n",
130			 usb_phy->chg_state);
131		return;
132	}
133
134	snprintf(uchger_type, ARRAY_SIZE(uchger_type),
135		 "USB_CHARGER_TYPE=%s", usb_chger_type[usb_phy->chg_type]);
136	kobject_uevent_env(&usb_phy->dev->kobj, KOBJ_CHANGE, envp);
137}
138
139static void __usb_phy_get_charger_type(struct usb_phy *usb_phy)
140{
141	if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_SDP) > 0) {
142		usb_phy->chg_type = SDP_TYPE;
143		usb_phy->chg_state = USB_CHARGER_PRESENT;
144	} else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_CDP) > 0) {
145		usb_phy->chg_type = CDP_TYPE;
146		usb_phy->chg_state = USB_CHARGER_PRESENT;
147	} else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_DCP) > 0) {
148		usb_phy->chg_type = DCP_TYPE;
149		usb_phy->chg_state = USB_CHARGER_PRESENT;
150	} else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_ACA) > 0) {
151		usb_phy->chg_type = ACA_TYPE;
152		usb_phy->chg_state = USB_CHARGER_PRESENT;
153	} else {
154		usb_phy->chg_type = UNKNOWN_TYPE;
155		usb_phy->chg_state = USB_CHARGER_ABSENT;
156	}
157
158	schedule_work(&usb_phy->chg_work);
159}
160
161/**
162 * usb_phy_get_charger_type - get charger type from extcon subsystem
163 * @nb: the notifier block to determine charger type
164 * @state: the cable state
165 * @data: private data
166 *
167 * Determin the charger type from extcon subsystem which also means the
168 * charger state has been chaned, then we should notify this event.
169 */
170static int usb_phy_get_charger_type(struct notifier_block *nb,
171				    unsigned long state, void *data)
172{
173	struct usb_phy *usb_phy = container_of(nb, struct usb_phy, type_nb);
174
175	__usb_phy_get_charger_type(usb_phy);
176	return NOTIFY_OK;
177}
178
179/**
180 * usb_phy_set_charger_current - set the USB charger current
181 * @usb_phy: the USB phy to be used
182 * @mA: the current need to be set
183 *
184 * Usually we only change the charger default current when USB finished the
185 * enumeration as one SDP charger. As one SDP charger, usb_phy_set_power()
186 * will issue this function to change charger current when after setting USB
187 * configuration, or suspend/resume USB. For other type charger, we should
188 * use the default charger current and we do not suggest to issue this function
189 * to change the charger current.
190 *
191 * When USB charger current has been changed, we need to notify the power users.
192 */
193void usb_phy_set_charger_current(struct usb_phy *usb_phy, unsigned int mA)
194{
195	switch (usb_phy->chg_type) {
196	case SDP_TYPE:
197		if (usb_phy->chg_cur.sdp_max == mA)
198			return;
199
200		usb_phy->chg_cur.sdp_max = (mA > DEFAULT_SDP_CUR_MAX_SS) ?
201			DEFAULT_SDP_CUR_MAX_SS : mA;
202		break;
203	case DCP_TYPE:
204		if (usb_phy->chg_cur.dcp_max == mA)
205			return;
206
207		usb_phy->chg_cur.dcp_max = (mA > DEFAULT_DCP_CUR_MAX) ?
208			DEFAULT_DCP_CUR_MAX : mA;
209		break;
210	case CDP_TYPE:
211		if (usb_phy->chg_cur.cdp_max == mA)
212			return;
213
214		usb_phy->chg_cur.cdp_max = (mA > DEFAULT_CDP_CUR_MAX) ?
215			DEFAULT_CDP_CUR_MAX : mA;
216		break;
217	case ACA_TYPE:
218		if (usb_phy->chg_cur.aca_max == mA)
219			return;
220
221		usb_phy->chg_cur.aca_max = (mA > DEFAULT_ACA_CUR_MAX) ?
222			DEFAULT_ACA_CUR_MAX : mA;
223		break;
224	default:
225		return;
226	}
227
228	schedule_work(&usb_phy->chg_work);
229}
230EXPORT_SYMBOL_GPL(usb_phy_set_charger_current);
231
232/**
233 * usb_phy_get_charger_current - get the USB charger current
234 * @usb_phy: the USB phy to be used
235 * @min: the minimum current
236 * @max: the maximum current
237 *
238 * Usually we will notify the maximum current to power user, but for some
239 * special case, power user also need the minimum current value. Then the
240 * power user can issue this function to get the suitable current.
241 */
242void usb_phy_get_charger_current(struct usb_phy *usb_phy,
243				 unsigned int *min, unsigned int *max)
244{
245	switch (usb_phy->chg_type) {
246	case SDP_TYPE:
247		*min = usb_phy->chg_cur.sdp_min;
248		*max = usb_phy->chg_cur.sdp_max;
249		break;
250	case DCP_TYPE:
251		*min = usb_phy->chg_cur.dcp_min;
252		*max = usb_phy->chg_cur.dcp_max;
253		break;
254	case CDP_TYPE:
255		*min = usb_phy->chg_cur.cdp_min;
256		*max = usb_phy->chg_cur.cdp_max;
257		break;
258	case ACA_TYPE:
259		*min = usb_phy->chg_cur.aca_min;
260		*max = usb_phy->chg_cur.aca_max;
261		break;
262	default:
263		*min = 0;
264		*max = 0;
265		break;
266	}
267}
268EXPORT_SYMBOL_GPL(usb_phy_get_charger_current);
269
270/**
271 * usb_phy_set_charger_state - set the USB charger state
272 * @usb_phy: the USB phy to be used
273 * @state: the new state need to be set for charger
274 *
275 * The usb phy driver can issue this function when the usb phy driver
276 * detected the charger state has been changed, in this case the charger
277 * type should be get from ->charger_detect().
278 */
279void usb_phy_set_charger_state(struct usb_phy *usb_phy,
280			       enum usb_charger_state state)
281{
282	if (usb_phy->chg_state == state || !usb_phy->charger_detect)
283		return;
284
285	usb_phy->chg_state = state;
286	if (usb_phy->chg_state == USB_CHARGER_PRESENT)
287		usb_phy->chg_type = usb_phy->charger_detect(usb_phy);
288	else
289		usb_phy->chg_type = UNKNOWN_TYPE;
290
291	schedule_work(&usb_phy->chg_work);
292}
293EXPORT_SYMBOL_GPL(usb_phy_set_charger_state);
294
295static void devm_usb_phy_release(struct device *dev, void *res)
296{
297	struct usb_phy *phy = *(struct usb_phy **)res;
298
299	usb_put_phy(phy);
300}
301
302static void devm_usb_phy_release2(struct device *dev, void *_res)
303{
304	struct phy_devm *res = _res;
305
306	if (res->nb)
307		usb_unregister_notifier(res->phy, res->nb);
308	usb_put_phy(res->phy);
309}
310
311static int devm_usb_phy_match(struct device *dev, void *res, void *match_data)
312{
313	struct usb_phy **phy = res;
314
315	return *phy == match_data;
316}
317
318static void usb_charger_init(struct usb_phy *usb_phy)
319{
320	usb_phy->chg_type = UNKNOWN_TYPE;
321	usb_phy->chg_state = USB_CHARGER_DEFAULT;
322	usb_phy_set_default_current(usb_phy);
323	INIT_WORK(&usb_phy->chg_work, usb_phy_notify_charger_work);
324}
325
326static int usb_add_extcon(struct usb_phy *x)
327{
328	int ret;
329
330	if (of_property_read_bool(x->dev->of_node, "extcon")) {
331		x->edev = extcon_get_edev_by_phandle(x->dev, 0);
332		if (IS_ERR(x->edev))
333			return PTR_ERR(x->edev);
334
335		x->id_edev = extcon_get_edev_by_phandle(x->dev, 1);
336		if (IS_ERR(x->id_edev)) {
337			x->id_edev = NULL;
338			dev_info(x->dev, "No separate ID extcon device\n");
339		}
340
341		if (x->vbus_nb.notifier_call) {
342			ret = devm_extcon_register_notifier(x->dev, x->edev,
343							    EXTCON_USB,
344							    &x->vbus_nb);
345			if (ret < 0) {
346				dev_err(x->dev,
347					"register VBUS notifier failed\n");
348				return ret;
349			}
350		} else {
351			x->type_nb.notifier_call = usb_phy_get_charger_type;
352
353			ret = devm_extcon_register_notifier(x->dev, x->edev,
354							    EXTCON_CHG_USB_SDP,
355							    &x->type_nb);
356			if (ret) {
357				dev_err(x->dev,
358					"register extcon USB SDP failed.\n");
359				return ret;
360			}
361
362			ret = devm_extcon_register_notifier(x->dev, x->edev,
363							    EXTCON_CHG_USB_CDP,
364							    &x->type_nb);
365			if (ret) {
366				dev_err(x->dev,
367					"register extcon USB CDP failed.\n");
368				return ret;
369			}
370
371			ret = devm_extcon_register_notifier(x->dev, x->edev,
372							    EXTCON_CHG_USB_DCP,
373							    &x->type_nb);
374			if (ret) {
375				dev_err(x->dev,
376					"register extcon USB DCP failed.\n");
377				return ret;
378			}
379
380			ret = devm_extcon_register_notifier(x->dev, x->edev,
381							    EXTCON_CHG_USB_ACA,
382							    &x->type_nb);
383			if (ret) {
384				dev_err(x->dev,
385					"register extcon USB ACA failed.\n");
386				return ret;
387			}
388		}
389
390		if (x->id_nb.notifier_call) {
391			struct extcon_dev *id_ext;
392
393			if (x->id_edev)
394				id_ext = x->id_edev;
395			else
396				id_ext = x->edev;
397
398			ret = devm_extcon_register_notifier(x->dev, id_ext,
399							    EXTCON_USB_HOST,
400							    &x->id_nb);
401			if (ret < 0) {
402				dev_err(x->dev,
403					"register ID notifier failed\n");
404				return ret;
405			}
406		}
407	}
408
409	if (x->type_nb.notifier_call)
410		__usb_phy_get_charger_type(x);
411
412	return 0;
413}
414
415/**
416 * devm_usb_get_phy - find the USB PHY
417 * @dev: device that requests this phy
418 * @type: the type of the phy the controller requires
419 *
420 * Gets the phy using usb_get_phy(), and associates a device with it using
421 * devres. On driver detach, release function is invoked on the devres data,
422 * then, devres data is freed.
423 *
424 * For use by USB host and peripheral drivers.
425 */
426struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type)
427{
428	struct usb_phy **ptr, *phy;
429
430	ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
431	if (!ptr)
432		return ERR_PTR(-ENOMEM);
433
434	phy = usb_get_phy(type);
435	if (!IS_ERR(phy)) {
436		*ptr = phy;
437		devres_add(dev, ptr);
438	} else
439		devres_free(ptr);
440
441	return phy;
442}
443EXPORT_SYMBOL_GPL(devm_usb_get_phy);
444
445/**
446 * usb_get_phy - find the USB PHY
447 * @type: the type of the phy the controller requires
448 *
449 * Returns the phy driver, after getting a refcount to it; or
450 * -ENODEV if there is no such phy.  The caller is responsible for
451 * calling usb_put_phy() to release that count.
452 *
453 * For use by USB host and peripheral drivers.
454 */
455struct usb_phy *usb_get_phy(enum usb_phy_type type)
456{
457	struct usb_phy	*phy = NULL;
458	unsigned long	flags;
459
460	spin_lock_irqsave(&phy_lock, flags);
461
462	phy = __usb_find_phy(&phy_list, type);
463	if (IS_ERR(phy) || !try_module_get(phy->dev->driver->owner)) {
464		pr_debug("PHY: unable to find transceiver of type %s\n",
465			usb_phy_type_string(type));
466		if (!IS_ERR(phy))
467			phy = ERR_PTR(-ENODEV);
468
469		goto err0;
470	}
471
472	get_device(phy->dev);
473
474err0:
475	spin_unlock_irqrestore(&phy_lock, flags);
476
477	return phy;
478}
479EXPORT_SYMBOL_GPL(usb_get_phy);
480
481/**
482 * devm_usb_get_phy_by_node - find the USB PHY by device_node
483 * @dev: device that requests this phy
484 * @node: the device_node for the phy device.
485 * @nb: a notifier_block to register with the phy.
486 *
487 * Returns the phy driver associated with the given device_node,
488 * after getting a refcount to it, -ENODEV if there is no such phy or
489 * -EPROBE_DEFER if the device is not yet loaded. While at that, it
490 * also associates the device with
491 * the phy using devres. On driver detach, release function is invoked
492 * on the devres data, then, devres data is freed.
493 *
494 * For use by peripheral drivers for devices related to a phy,
495 * such as a charger.
496 */
497struct  usb_phy *devm_usb_get_phy_by_node(struct device *dev,
498					  struct device_node *node,
499					  struct notifier_block *nb)
500{
501	struct usb_phy	*phy = ERR_PTR(-ENOMEM);
502	struct phy_devm	*ptr;
503	unsigned long	flags;
504
505	ptr = devres_alloc(devm_usb_phy_release2, sizeof(*ptr), GFP_KERNEL);
506	if (!ptr) {
507		dev_dbg(dev, "failed to allocate memory for devres\n");
508		goto err0;
509	}
510
511	spin_lock_irqsave(&phy_lock, flags);
512
513	phy = __of_usb_find_phy(node);
514	if (IS_ERR(phy)) {
515		devres_free(ptr);
516		goto err1;
517	}
518
519	if (!try_module_get(phy->dev->driver->owner)) {
520		phy = ERR_PTR(-ENODEV);
521		devres_free(ptr);
522		goto err1;
523	}
524	if (nb)
525		usb_register_notifier(phy, nb);
526	ptr->phy = phy;
527	ptr->nb = nb;
528	devres_add(dev, ptr);
529
530	get_device(phy->dev);
531
532err1:
533	spin_unlock_irqrestore(&phy_lock, flags);
534
535err0:
536
537	return phy;
538}
539EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_node);
540
541/**
542 * devm_usb_get_phy_by_phandle - find the USB PHY by phandle
543 * @dev: device that requests this phy
544 * @phandle: name of the property holding the phy phandle value
545 * @index: the index of the phy
546 *
547 * Returns the phy driver associated with the given phandle value,
548 * after getting a refcount to it, -ENODEV if there is no such phy or
549 * -EPROBE_DEFER if there is a phandle to the phy, but the device is
550 * not yet loaded. While at that, it also associates the device with
551 * the phy using devres. On driver detach, release function is invoked
552 * on the devres data, then, devres data is freed.
553 *
554 * For use by USB host and peripheral drivers.
555 */
556struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev,
557	const char *phandle, u8 index)
558{
559	struct device_node *node;
560	struct usb_phy	*phy;
561
562	if (!dev->of_node) {
563		dev_dbg(dev, "device does not have a device node entry\n");
564		return ERR_PTR(-EINVAL);
565	}
566
567	node = of_parse_phandle(dev->of_node, phandle, index);
568	if (!node) {
569		dev_dbg(dev, "failed to get %s phandle in %pOF node\n", phandle,
570			dev->of_node);
571		return ERR_PTR(-ENODEV);
572	}
573	phy = devm_usb_get_phy_by_node(dev, node, NULL);
574	of_node_put(node);
575	return phy;
576}
577EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_phandle);
578
579/**
580 * devm_usb_put_phy - release the USB PHY
581 * @dev: device that wants to release this phy
582 * @phy: the phy returned by devm_usb_get_phy()
583 *
584 * destroys the devres associated with this phy and invokes usb_put_phy
585 * to release the phy.
586 *
587 * For use by USB host and peripheral drivers.
588 */
589void devm_usb_put_phy(struct device *dev, struct usb_phy *phy)
590{
591	int r;
592
593	r = devres_destroy(dev, devm_usb_phy_release, devm_usb_phy_match, phy);
594	dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
595}
596EXPORT_SYMBOL_GPL(devm_usb_put_phy);
597
598/**
599 * usb_put_phy - release the USB PHY
600 * @x: the phy returned by usb_get_phy()
601 *
602 * Releases a refcount the caller received from usb_get_phy().
603 *
604 * For use by USB host and peripheral drivers.
605 */
606void usb_put_phy(struct usb_phy *x)
607{
608	if (x) {
609		struct module *owner = x->dev->driver->owner;
610
611		put_device(x->dev);
612		module_put(owner);
613	}
614}
615EXPORT_SYMBOL_GPL(usb_put_phy);
616
617/**
618 * usb_add_phy: declare the USB PHY
619 * @x: the USB phy to be used; or NULL
620 * @type: the type of this PHY
621 *
622 * This call is exclusively for use by phy drivers, which
623 * coordinate the activities of drivers for host and peripheral
624 * controllers, and in some cases for VBUS current regulation.
625 */
626int usb_add_phy(struct usb_phy *x, enum usb_phy_type type)
627{
628	int		ret = 0;
629	unsigned long	flags;
630	struct usb_phy	*phy;
631
632	if (x->type != USB_PHY_TYPE_UNDEFINED) {
633		dev_err(x->dev, "not accepting initialized PHY %s\n", x->label);
634		return -EINVAL;
635	}
636
637	usb_charger_init(x);
638	ret = usb_add_extcon(x);
639	if (ret)
640		return ret;
641
642	ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier);
643
644	spin_lock_irqsave(&phy_lock, flags);
645
646	list_for_each_entry(phy, &phy_list, head) {
647		if (phy->type == type) {
648			ret = -EBUSY;
649			dev_err(x->dev, "transceiver type %s already exists\n",
650						usb_phy_type_string(type));
651			goto out;
652		}
653	}
654
655	x->type = type;
656	list_add_tail(&x->head, &phy_list);
657
658out:
659	spin_unlock_irqrestore(&phy_lock, flags);
660	return ret;
661}
662EXPORT_SYMBOL_GPL(usb_add_phy);
663
664/**
665 * usb_add_phy_dev - declare the USB PHY
666 * @x: the USB phy to be used; or NULL
667 *
668 * This call is exclusively for use by phy drivers, which
669 * coordinate the activities of drivers for host and peripheral
670 * controllers, and in some cases for VBUS current regulation.
671 */
672int usb_add_phy_dev(struct usb_phy *x)
673{
674	unsigned long flags;
675	int ret;
676
677	if (!x->dev) {
678		dev_err(x->dev, "no device provided for PHY\n");
679		return -EINVAL;
680	}
681
682	usb_charger_init(x);
683	ret = usb_add_extcon(x);
684	if (ret)
685		return ret;
686
687	ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier);
688
689	spin_lock_irqsave(&phy_lock, flags);
690	list_add_tail(&x->head, &phy_list);
691	spin_unlock_irqrestore(&phy_lock, flags);
692
693	return 0;
694}
695EXPORT_SYMBOL_GPL(usb_add_phy_dev);
696
697/**
698 * usb_remove_phy - remove the OTG PHY
699 * @x: the USB OTG PHY to be removed;
700 *
701 * This reverts the effects of usb_add_phy
702 */
703void usb_remove_phy(struct usb_phy *x)
704{
705	unsigned long	flags;
706
707	spin_lock_irqsave(&phy_lock, flags);
708	if (x)
709		list_del(&x->head);
710	spin_unlock_irqrestore(&phy_lock, flags);
711}
712EXPORT_SYMBOL_GPL(usb_remove_phy);
713
714/**
715 * usb_phy_set_event - set event to phy event
716 * @x: the phy returned by usb_get_phy();
717 * @event: event to set
718 *
719 * This sets event to phy event
720 */
721void usb_phy_set_event(struct usb_phy *x, unsigned long event)
722{
723	x->last_event = event;
724}
725EXPORT_SYMBOL_GPL(usb_phy_set_event);