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 const char *const usb_chger_state[] = {
46 [USB_CHARGER_DEFAULT] = "USB_CHARGER_DEFAULT",
47 [USB_CHARGER_PRESENT] = "USB_CHARGER_PRESENT",
48 [USB_CHARGER_ABSENT] = "USB_CHARGER_ABSENT",
49};
50
51static struct usb_phy *__usb_find_phy(struct list_head *list,
52 enum usb_phy_type type)
53{
54 struct usb_phy *phy = NULL;
55
56 list_for_each_entry(phy, list, head) {
57 if (phy->type != type)
58 continue;
59
60 return phy;
61 }
62
63 return ERR_PTR(error: -ENODEV);
64}
65
66static struct usb_phy *__of_usb_find_phy(struct device_node *node)
67{
68 struct usb_phy *phy;
69
70 if (!of_device_is_available(device: node))
71 return ERR_PTR(error: -ENODEV);
72
73 list_for_each_entry(phy, &phy_list, head) {
74 if (node != phy->dev->of_node)
75 continue;
76
77 return phy;
78 }
79
80 return ERR_PTR(error: -EPROBE_DEFER);
81}
82
83static struct usb_phy *__device_to_usb_phy(const struct device *dev)
84{
85 struct usb_phy *usb_phy;
86
87 list_for_each_entry(usb_phy, &phy_list, head) {
88 if (usb_phy->dev == dev)
89 return usb_phy;
90 }
91
92 return NULL;
93}
94
95static void usb_phy_set_default_current(struct usb_phy *usb_phy)
96{
97 usb_phy->chg_cur.sdp_min = DEFAULT_SDP_CUR_MIN;
98 usb_phy->chg_cur.sdp_max = DEFAULT_SDP_CUR_MAX;
99 usb_phy->chg_cur.dcp_min = DEFAULT_DCP_CUR_MIN;
100 usb_phy->chg_cur.dcp_max = DEFAULT_DCP_CUR_MAX;
101 usb_phy->chg_cur.cdp_min = DEFAULT_CDP_CUR_MIN;
102 usb_phy->chg_cur.cdp_max = DEFAULT_CDP_CUR_MAX;
103 usb_phy->chg_cur.aca_min = DEFAULT_ACA_CUR_MIN;
104 usb_phy->chg_cur.aca_max = DEFAULT_ACA_CUR_MAX;
105}
106
107/**
108 * usb_phy_notify_charger_work - notify the USB charger state
109 * @work: the charger work to notify the USB charger state
110 *
111 * This work can be issued when USB charger state has been changed or
112 * USB charger current has been changed, then we can notify the current
113 * what can be drawn to power user and the charger state to userspace.
114 *
115 * If we get the charger type from extcon subsystem, we can notify the
116 * charger state to power user automatically by usb_phy_get_charger_type()
117 * issuing from extcon subsystem.
118 *
119 * If we get the charger type from ->charger_detect() instead of extcon
120 * subsystem, the usb phy driver should issue usb_phy_set_charger_state()
121 * to set charger state when the charger state has been changed.
122 */
123static void usb_phy_notify_charger_work(struct work_struct *work)
124{
125 struct usb_phy *usb_phy = container_of(work, struct usb_phy, chg_work);
126 unsigned int min, max;
127
128 switch (usb_phy->chg_state) {
129 case USB_CHARGER_PRESENT:
130 usb_phy_get_charger_current(usb_phy, min: &min, max: &max);
131
132 atomic_notifier_call_chain(nh: &usb_phy->notifier, val: max, v: usb_phy);
133 break;
134 case USB_CHARGER_ABSENT:
135 usb_phy_set_default_current(usb_phy);
136
137 atomic_notifier_call_chain(nh: &usb_phy->notifier, val: 0, v: usb_phy);
138 break;
139 default:
140 dev_warn(usb_phy->dev, "Unknown USB charger state: %d\n",
141 usb_phy->chg_state);
142 return;
143 }
144
145 kobject_uevent(kobj: &usb_phy->dev->kobj, action: KOBJ_CHANGE);
146}
147
148static int usb_phy_uevent(const struct device *dev, struct kobj_uevent_env *env)
149{
150 const struct usb_phy *usb_phy;
151 char uchger_state[50] = { 0 };
152 char uchger_type[50] = { 0 };
153 unsigned long flags;
154
155 spin_lock_irqsave(&phy_lock, flags);
156 usb_phy = __device_to_usb_phy(dev);
157 spin_unlock_irqrestore(lock: &phy_lock, flags);
158
159 if (!usb_phy)
160 return -ENODEV;
161
162 snprintf(buf: uchger_state, ARRAY_SIZE(uchger_state),
163 fmt: "USB_CHARGER_STATE=%s", usb_chger_state[usb_phy->chg_state]);
164
165 snprintf(buf: uchger_type, ARRAY_SIZE(uchger_type),
166 fmt: "USB_CHARGER_TYPE=%s", usb_chger_type[usb_phy->chg_type]);
167
168 if (add_uevent_var(env, format: uchger_state))
169 return -ENOMEM;
170
171 if (add_uevent_var(env, format: uchger_type))
172 return -ENOMEM;
173
174 return 0;
175}
176
177static void __usb_phy_get_charger_type(struct usb_phy *usb_phy)
178{
179 if (extcon_get_state(edev: usb_phy->edev, EXTCON_CHG_USB_SDP) > 0) {
180 usb_phy->chg_type = SDP_TYPE;
181 usb_phy->chg_state = USB_CHARGER_PRESENT;
182 } else if (extcon_get_state(edev: usb_phy->edev, EXTCON_CHG_USB_CDP) > 0) {
183 usb_phy->chg_type = CDP_TYPE;
184 usb_phy->chg_state = USB_CHARGER_PRESENT;
185 } else if (extcon_get_state(edev: usb_phy->edev, EXTCON_CHG_USB_DCP) > 0) {
186 usb_phy->chg_type = DCP_TYPE;
187 usb_phy->chg_state = USB_CHARGER_PRESENT;
188 } else if (extcon_get_state(edev: usb_phy->edev, EXTCON_CHG_USB_ACA) > 0) {
189 usb_phy->chg_type = ACA_TYPE;
190 usb_phy->chg_state = USB_CHARGER_PRESENT;
191 } else {
192 usb_phy->chg_type = UNKNOWN_TYPE;
193 usb_phy->chg_state = USB_CHARGER_ABSENT;
194 }
195
196 schedule_work(work: &usb_phy->chg_work);
197}
198
199/**
200 * usb_phy_get_charger_type - get charger type from extcon subsystem
201 * @nb: the notifier block to determine charger type
202 * @state: the cable state
203 * @data: private data
204 *
205 * Determin the charger type from extcon subsystem which also means the
206 * charger state has been chaned, then we should notify this event.
207 */
208static int usb_phy_get_charger_type(struct notifier_block *nb,
209 unsigned long state, void *data)
210{
211 struct usb_phy *usb_phy = container_of(nb, struct usb_phy, type_nb);
212
213 __usb_phy_get_charger_type(usb_phy);
214 return NOTIFY_OK;
215}
216
217/**
218 * usb_phy_set_charger_current - set the USB charger current
219 * @usb_phy: the USB phy to be used
220 * @mA: the current need to be set
221 *
222 * Usually we only change the charger default current when USB finished the
223 * enumeration as one SDP charger. As one SDP charger, usb_phy_set_power()
224 * will issue this function to change charger current when after setting USB
225 * configuration, or suspend/resume USB. For other type charger, we should
226 * use the default charger current and we do not suggest to issue this function
227 * to change the charger current.
228 *
229 * When USB charger current has been changed, we need to notify the power users.
230 */
231void usb_phy_set_charger_current(struct usb_phy *usb_phy, unsigned int mA)
232{
233 switch (usb_phy->chg_type) {
234 case SDP_TYPE:
235 if (usb_phy->chg_cur.sdp_max == mA)
236 return;
237
238 usb_phy->chg_cur.sdp_max = (mA > DEFAULT_SDP_CUR_MAX_SS) ?
239 DEFAULT_SDP_CUR_MAX_SS : mA;
240 break;
241 case DCP_TYPE:
242 if (usb_phy->chg_cur.dcp_max == mA)
243 return;
244
245 usb_phy->chg_cur.dcp_max = (mA > DEFAULT_DCP_CUR_MAX) ?
246 DEFAULT_DCP_CUR_MAX : mA;
247 break;
248 case CDP_TYPE:
249 if (usb_phy->chg_cur.cdp_max == mA)
250 return;
251
252 usb_phy->chg_cur.cdp_max = (mA > DEFAULT_CDP_CUR_MAX) ?
253 DEFAULT_CDP_CUR_MAX : mA;
254 break;
255 case ACA_TYPE:
256 if (usb_phy->chg_cur.aca_max == mA)
257 return;
258
259 usb_phy->chg_cur.aca_max = (mA > DEFAULT_ACA_CUR_MAX) ?
260 DEFAULT_ACA_CUR_MAX : mA;
261 break;
262 default:
263 return;
264 }
265
266 schedule_work(work: &usb_phy->chg_work);
267}
268EXPORT_SYMBOL_GPL(usb_phy_set_charger_current);
269
270/**
271 * usb_phy_get_charger_current - get the USB charger current
272 * @usb_phy: the USB phy to be used
273 * @min: the minimum current
274 * @max: the maximum current
275 *
276 * Usually we will notify the maximum current to power user, but for some
277 * special case, power user also need the minimum current value. Then the
278 * power user can issue this function to get the suitable current.
279 */
280void usb_phy_get_charger_current(struct usb_phy *usb_phy,
281 unsigned int *min, unsigned int *max)
282{
283 switch (usb_phy->chg_type) {
284 case SDP_TYPE:
285 *min = usb_phy->chg_cur.sdp_min;
286 *max = usb_phy->chg_cur.sdp_max;
287 break;
288 case DCP_TYPE:
289 *min = usb_phy->chg_cur.dcp_min;
290 *max = usb_phy->chg_cur.dcp_max;
291 break;
292 case CDP_TYPE:
293 *min = usb_phy->chg_cur.cdp_min;
294 *max = usb_phy->chg_cur.cdp_max;
295 break;
296 case ACA_TYPE:
297 *min = usb_phy->chg_cur.aca_min;
298 *max = usb_phy->chg_cur.aca_max;
299 break;
300 default:
301 *min = 0;
302 *max = 0;
303 break;
304 }
305}
306EXPORT_SYMBOL_GPL(usb_phy_get_charger_current);
307
308/**
309 * usb_phy_set_charger_state - set the USB charger state
310 * @usb_phy: the USB phy to be used
311 * @state: the new state need to be set for charger
312 *
313 * The usb phy driver can issue this function when the usb phy driver
314 * detected the charger state has been changed, in this case the charger
315 * type should be get from ->charger_detect().
316 */
317void usb_phy_set_charger_state(struct usb_phy *usb_phy,
318 enum usb_charger_state state)
319{
320 if (usb_phy->chg_state == state || !usb_phy->charger_detect)
321 return;
322
323 usb_phy->chg_state = state;
324 if (usb_phy->chg_state == USB_CHARGER_PRESENT)
325 usb_phy->chg_type = usb_phy->charger_detect(usb_phy);
326 else
327 usb_phy->chg_type = UNKNOWN_TYPE;
328
329 schedule_work(work: &usb_phy->chg_work);
330}
331EXPORT_SYMBOL_GPL(usb_phy_set_charger_state);
332
333static void devm_usb_phy_release(struct device *dev, void *res)
334{
335 struct usb_phy *phy = *(struct usb_phy **)res;
336
337 usb_put_phy(phy);
338}
339
340static void devm_usb_phy_release2(struct device *dev, void *_res)
341{
342 struct phy_devm *res = _res;
343
344 if (res->nb)
345 usb_unregister_notifier(x: res->phy, nb: res->nb);
346 usb_put_phy(res->phy);
347}
348
349static int devm_usb_phy_match(struct device *dev, void *res, void *match_data)
350{
351 struct usb_phy **phy = res;
352
353 return *phy == match_data;
354}
355
356static void usb_charger_init(struct usb_phy *usb_phy)
357{
358 usb_phy->chg_type = UNKNOWN_TYPE;
359 usb_phy->chg_state = USB_CHARGER_DEFAULT;
360 usb_phy_set_default_current(usb_phy);
361 INIT_WORK(&usb_phy->chg_work, usb_phy_notify_charger_work);
362}
363
364static int usb_add_extcon(struct usb_phy *x)
365{
366 int ret;
367
368 if (of_property_read_bool(np: x->dev->of_node, propname: "extcon")) {
369 x->edev = extcon_get_edev_by_phandle(dev: x->dev, index: 0);
370 if (IS_ERR(ptr: x->edev))
371 return PTR_ERR(ptr: x->edev);
372
373 x->id_edev = extcon_get_edev_by_phandle(dev: x->dev, index: 1);
374 if (IS_ERR(ptr: x->id_edev)) {
375 x->id_edev = NULL;
376 dev_info(x->dev, "No separate ID extcon device\n");
377 }
378
379 if (x->vbus_nb.notifier_call) {
380 ret = devm_extcon_register_notifier(dev: x->dev, edev: x->edev,
381 EXTCON_USB,
382 nb: &x->vbus_nb);
383 if (ret < 0) {
384 dev_err(x->dev,
385 "register VBUS notifier failed\n");
386 return ret;
387 }
388 } else {
389 x->type_nb.notifier_call = usb_phy_get_charger_type;
390
391 ret = devm_extcon_register_notifier(dev: x->dev, edev: x->edev,
392 EXTCON_CHG_USB_SDP,
393 nb: &x->type_nb);
394 if (ret) {
395 dev_err(x->dev,
396 "register extcon USB SDP failed.\n");
397 return ret;
398 }
399
400 ret = devm_extcon_register_notifier(dev: x->dev, edev: x->edev,
401 EXTCON_CHG_USB_CDP,
402 nb: &x->type_nb);
403 if (ret) {
404 dev_err(x->dev,
405 "register extcon USB CDP failed.\n");
406 return ret;
407 }
408
409 ret = devm_extcon_register_notifier(dev: x->dev, edev: x->edev,
410 EXTCON_CHG_USB_DCP,
411 nb: &x->type_nb);
412 if (ret) {
413 dev_err(x->dev,
414 "register extcon USB DCP failed.\n");
415 return ret;
416 }
417
418 ret = devm_extcon_register_notifier(dev: x->dev, edev: x->edev,
419 EXTCON_CHG_USB_ACA,
420 nb: &x->type_nb);
421 if (ret) {
422 dev_err(x->dev,
423 "register extcon USB ACA failed.\n");
424 return ret;
425 }
426 }
427
428 if (x->id_nb.notifier_call) {
429 struct extcon_dev *id_ext;
430
431 if (x->id_edev)
432 id_ext = x->id_edev;
433 else
434 id_ext = x->edev;
435
436 ret = devm_extcon_register_notifier(dev: x->dev, edev: id_ext,
437 EXTCON_USB_HOST,
438 nb: &x->id_nb);
439 if (ret < 0) {
440 dev_err(x->dev,
441 "register ID notifier failed\n");
442 return ret;
443 }
444 }
445 }
446
447 if (x->type_nb.notifier_call)
448 __usb_phy_get_charger_type(usb_phy: x);
449
450 return 0;
451}
452
453/**
454 * devm_usb_get_phy - find the USB PHY
455 * @dev: device that requests this phy
456 * @type: the type of the phy the controller requires
457 *
458 * Gets the phy using usb_get_phy(), and associates a device with it using
459 * devres. On driver detach, release function is invoked on the devres data,
460 * then, devres data is freed.
461 *
462 * For use by USB host and peripheral drivers.
463 */
464struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type)
465{
466 struct usb_phy **ptr, *phy;
467
468 ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
469 if (!ptr)
470 return ERR_PTR(error: -ENOMEM);
471
472 phy = usb_get_phy(type);
473 if (!IS_ERR(ptr: phy)) {
474 *ptr = phy;
475 devres_add(dev, res: ptr);
476 } else
477 devres_free(res: ptr);
478
479 return phy;
480}
481EXPORT_SYMBOL_GPL(devm_usb_get_phy);
482
483/**
484 * usb_get_phy - find the USB PHY
485 * @type: the type of the phy the controller requires
486 *
487 * Returns the phy driver, after getting a refcount to it; or
488 * -ENODEV if there is no such phy. The caller is responsible for
489 * calling usb_put_phy() to release that count.
490 *
491 * For use by USB host and peripheral drivers.
492 */
493struct usb_phy *usb_get_phy(enum usb_phy_type type)
494{
495 struct usb_phy *phy = NULL;
496 unsigned long flags;
497
498 spin_lock_irqsave(&phy_lock, flags);
499
500 phy = __usb_find_phy(list: &phy_list, type);
501 if (IS_ERR(ptr: phy) || !try_module_get(module: phy->dev->driver->owner)) {
502 pr_debug("PHY: unable to find transceiver of type %s\n",
503 usb_phy_type_string(type));
504 if (!IS_ERR(ptr: phy))
505 phy = ERR_PTR(error: -ENODEV);
506
507 goto err0;
508 }
509
510 get_device(dev: phy->dev);
511
512err0:
513 spin_unlock_irqrestore(lock: &phy_lock, flags);
514
515 return phy;
516}
517EXPORT_SYMBOL_GPL(usb_get_phy);
518
519/**
520 * devm_usb_get_phy_by_node - find the USB PHY by device_node
521 * @dev: device that requests this phy
522 * @node: the device_node for the phy device.
523 * @nb: a notifier_block to register with the phy.
524 *
525 * Returns the phy driver associated with the given device_node,
526 * after getting a refcount to it, -ENODEV if there is no such phy or
527 * -EPROBE_DEFER if the device is not yet loaded. While at that, it
528 * also associates the device with
529 * the phy using devres. On driver detach, release function is invoked
530 * on the devres data, then, devres data is freed.
531 *
532 * For use by peripheral drivers for devices related to a phy,
533 * such as a charger.
534 */
535struct usb_phy *devm_usb_get_phy_by_node(struct device *dev,
536 struct device_node *node,
537 struct notifier_block *nb)
538{
539 struct usb_phy *phy = ERR_PTR(error: -ENOMEM);
540 struct phy_devm *ptr;
541 unsigned long flags;
542
543 ptr = devres_alloc(devm_usb_phy_release2, sizeof(*ptr), GFP_KERNEL);
544 if (!ptr) {
545 dev_dbg(dev, "failed to allocate memory for devres\n");
546 goto err0;
547 }
548
549 spin_lock_irqsave(&phy_lock, flags);
550
551 phy = __of_usb_find_phy(node);
552 if (IS_ERR(ptr: phy)) {
553 devres_free(res: ptr);
554 goto err1;
555 }
556
557 if (!try_module_get(module: phy->dev->driver->owner)) {
558 phy = ERR_PTR(error: -ENODEV);
559 devres_free(res: ptr);
560 goto err1;
561 }
562 if (nb)
563 usb_register_notifier(x: phy, nb);
564 ptr->phy = phy;
565 ptr->nb = nb;
566 devres_add(dev, res: ptr);
567
568 get_device(dev: phy->dev);
569
570err1:
571 spin_unlock_irqrestore(lock: &phy_lock, flags);
572
573err0:
574
575 return phy;
576}
577EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_node);
578
579/**
580 * devm_usb_get_phy_by_phandle - find the USB PHY by phandle
581 * @dev: device that requests this phy
582 * @phandle: name of the property holding the phy phandle value
583 * @index: the index of the phy
584 *
585 * Returns the phy driver associated with the given phandle value,
586 * after getting a refcount to it, -ENODEV if there is no such phy or
587 * -EPROBE_DEFER if there is a phandle to the phy, but the device is
588 * not yet loaded. While at that, it also associates the device with
589 * the phy using devres. On driver detach, release function is invoked
590 * on the devres data, then, devres data is freed.
591 *
592 * For use by USB host and peripheral drivers.
593 */
594struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev,
595 const char *phandle, u8 index)
596{
597 struct device_node *node;
598 struct usb_phy *phy;
599
600 if (!dev->of_node) {
601 dev_dbg(dev, "device does not have a device node entry\n");
602 return ERR_PTR(error: -EINVAL);
603 }
604
605 node = of_parse_phandle(np: dev->of_node, phandle_name: phandle, index);
606 if (!node) {
607 dev_dbg(dev, "failed to get %s phandle in %pOF node\n", phandle,
608 dev->of_node);
609 return ERR_PTR(error: -ENODEV);
610 }
611 phy = devm_usb_get_phy_by_node(dev, node, NULL);
612 of_node_put(node);
613 return phy;
614}
615EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_phandle);
616
617/**
618 * devm_usb_put_phy - release the USB PHY
619 * @dev: device that wants to release this phy
620 * @phy: the phy returned by devm_usb_get_phy()
621 *
622 * destroys the devres associated with this phy and invokes usb_put_phy
623 * to release the phy.
624 *
625 * For use by USB host and peripheral drivers.
626 */
627void devm_usb_put_phy(struct device *dev, struct usb_phy *phy)
628{
629 int r;
630
631 r = devres_destroy(dev, release: devm_usb_phy_release, match: devm_usb_phy_match, match_data: phy);
632 dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
633}
634EXPORT_SYMBOL_GPL(devm_usb_put_phy);
635
636/**
637 * usb_put_phy - release the USB PHY
638 * @x: the phy returned by usb_get_phy()
639 *
640 * Releases a refcount the caller received from usb_get_phy().
641 *
642 * For use by USB host and peripheral drivers.
643 */
644void usb_put_phy(struct usb_phy *x)
645{
646 if (x) {
647 struct module *owner = x->dev->driver->owner;
648
649 put_device(dev: x->dev);
650 module_put(module: owner);
651 }
652}
653EXPORT_SYMBOL_GPL(usb_put_phy);
654
655/**
656 * usb_add_phy: declare the USB PHY
657 * @x: the USB phy to be used; or NULL
658 * @type: the type of this PHY
659 *
660 * This call is exclusively for use by phy drivers, which
661 * coordinate the activities of drivers for host and peripheral
662 * controllers, and in some cases for VBUS current regulation.
663 */
664int usb_add_phy(struct usb_phy *x, enum usb_phy_type type)
665{
666 int ret = 0;
667 unsigned long flags;
668 struct usb_phy *phy;
669
670 if (x->type != USB_PHY_TYPE_UNDEFINED) {
671 dev_err(x->dev, "not accepting initialized PHY %s\n", x->label);
672 return -EINVAL;
673 }
674
675 usb_charger_init(usb_phy: x);
676 ret = usb_add_extcon(x);
677 if (ret)
678 return ret;
679
680 ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier);
681
682 spin_lock_irqsave(&phy_lock, flags);
683
684 list_for_each_entry(phy, &phy_list, head) {
685 if (phy->type == type) {
686 ret = -EBUSY;
687 dev_err(x->dev, "transceiver type %s already exists\n",
688 usb_phy_type_string(type));
689 goto out;
690 }
691 }
692
693 x->type = type;
694 list_add_tail(new: &x->head, head: &phy_list);
695
696out:
697 spin_unlock_irqrestore(lock: &phy_lock, flags);
698 return ret;
699}
700EXPORT_SYMBOL_GPL(usb_add_phy);
701
702static const struct device_type usb_phy_dev_type = {
703 .name = "usb_phy",
704 .uevent = usb_phy_uevent,
705};
706
707/**
708 * usb_add_phy_dev - declare the USB PHY
709 * @x: the USB phy to be used; or NULL
710 *
711 * This call is exclusively for use by phy drivers, which
712 * coordinate the activities of drivers for host and peripheral
713 * controllers, and in some cases for VBUS current regulation.
714 */
715int usb_add_phy_dev(struct usb_phy *x)
716{
717 unsigned long flags;
718 int ret;
719
720 if (!x->dev) {
721 dev_err(x->dev, "no device provided for PHY\n");
722 return -EINVAL;
723 }
724
725 usb_charger_init(usb_phy: x);
726 ret = usb_add_extcon(x);
727 if (ret)
728 return ret;
729
730 x->dev->type = &usb_phy_dev_type;
731
732 ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier);
733
734 spin_lock_irqsave(&phy_lock, flags);
735 list_add_tail(new: &x->head, head: &phy_list);
736 spin_unlock_irqrestore(lock: &phy_lock, flags);
737
738 return 0;
739}
740EXPORT_SYMBOL_GPL(usb_add_phy_dev);
741
742/**
743 * usb_remove_phy - remove the OTG PHY
744 * @x: the USB OTG PHY to be removed;
745 *
746 * This reverts the effects of usb_add_phy
747 */
748void usb_remove_phy(struct usb_phy *x)
749{
750 unsigned long flags;
751
752 spin_lock_irqsave(&phy_lock, flags);
753 if (x)
754 list_del(entry: &x->head);
755 spin_unlock_irqrestore(lock: &phy_lock, flags);
756}
757EXPORT_SYMBOL_GPL(usb_remove_phy);
758
759/**
760 * usb_phy_set_event - set event to phy event
761 * @x: the phy returned by usb_get_phy();
762 * @event: event to set
763 *
764 * This sets event to phy event
765 */
766void usb_phy_set_event(struct usb_phy *x, unsigned long event)
767{
768 x->last_event = event;
769}
770EXPORT_SYMBOL_GPL(usb_phy_set_event);
771

source code of linux/drivers/usb/phy/phy.c