xref: /linux/drivers/usb/core/phy.c (revision c715f13bb30f9f4d1bd8888667ef32e43b6fedc1)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * A wrapper for multiple PHYs which passes all phy_* function calls to
4  * multiple (actual) PHY devices. This is comes handy when initializing
5  * all PHYs on a HCD and to keep them all in the same state.
6  *
7  * Copyright (C) 2018 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
8  */
9 
10 #include <linux/device.h>
11 #include <linux/list.h>
12 #include <linux/phy/phy.h>
13 #include <linux/of.h>
14 
15 #include "phy.h"
16 
17 struct usb_phy_roothub {
18 	struct phy		*phy;
19 	struct list_head	list;
20 };
21 
22 /* Allocate the roothub_entry by specific name of phy */
23 static int usb_phy_roothub_add_phy_by_name(struct device *dev, const char *name,
24 					   struct list_head *list)
25 {
26 	struct usb_phy_roothub *roothub_entry;
27 	struct phy *phy;
28 
29 	phy = devm_of_phy_get(dev, dev->of_node, name);
30 	if (IS_ERR(phy))
31 		return PTR_ERR(phy);
32 
33 	roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL);
34 	if (!roothub_entry)
35 		return -ENOMEM;
36 
37 	INIT_LIST_HEAD(&roothub_entry->list);
38 
39 	roothub_entry->phy = phy;
40 
41 	list_add_tail(&roothub_entry->list, list);
42 
43 	return 0;
44 }
45 
46 static int usb_phy_roothub_add_phy(struct device *dev, int index,
47 				   struct list_head *list)
48 {
49 	struct usb_phy_roothub *roothub_entry;
50 	struct phy *phy;
51 
52 	phy = devm_of_phy_get_by_index(dev, dev->of_node, index);
53 	if (IS_ERR(phy)) {
54 		if (PTR_ERR(phy) == -ENODEV)
55 			return 0;
56 		else
57 			return PTR_ERR(phy);
58 	}
59 
60 	roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL);
61 	if (!roothub_entry)
62 		return -ENOMEM;
63 
64 	INIT_LIST_HEAD(&roothub_entry->list);
65 
66 	roothub_entry->phy = phy;
67 
68 	list_add_tail(&roothub_entry->list, list);
69 
70 	return 0;
71 }
72 
73 struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev)
74 {
75 	struct usb_phy_roothub *phy_roothub;
76 	int i, num_phys, err;
77 
78 	if (!IS_ENABLED(CONFIG_GENERIC_PHY))
79 		return NULL;
80 
81 	num_phys = of_count_phandle_with_args(dev->of_node, "phys",
82 					      "#phy-cells");
83 	if (num_phys <= 0)
84 		return NULL;
85 
86 	phy_roothub = devm_kzalloc(dev, sizeof(*phy_roothub), GFP_KERNEL);
87 	if (!phy_roothub)
88 		return ERR_PTR(-ENOMEM);
89 
90 	INIT_LIST_HEAD(&phy_roothub->list);
91 
92 	if (!usb_phy_roothub_add_phy_by_name(dev, "usb2-phy", &phy_roothub->list))
93 		return phy_roothub;
94 
95 	for (i = 0; i < num_phys; i++) {
96 		err = usb_phy_roothub_add_phy(dev, i, &phy_roothub->list);
97 		if (err)
98 			return ERR_PTR(err);
99 	}
100 
101 	return phy_roothub;
102 }
103 EXPORT_SYMBOL_GPL(usb_phy_roothub_alloc);
104 
105 /**
106  * usb_phy_roothub_alloc_usb3_phy - alloc the roothub
107  * @dev: the device of the host controller
108  *
109  * Allocate the usb phy roothub if the host use a generic usb3-phy.
110  *
111  * Return: On success, a pointer to the usb_phy_roothub. Otherwise,
112  * %NULL if no use usb3 phy or %-ENOMEM if out of memory.
113  */
114 struct usb_phy_roothub *usb_phy_roothub_alloc_usb3_phy(struct device *dev)
115 {
116 	struct usb_phy_roothub *phy_roothub;
117 	int num_phys;
118 
119 	if (!IS_ENABLED(CONFIG_GENERIC_PHY))
120 		return NULL;
121 
122 	num_phys = of_count_phandle_with_args(dev->of_node, "phys",
123 					      "#phy-cells");
124 	if (num_phys <= 0)
125 		return NULL;
126 
127 	phy_roothub = devm_kzalloc(dev, sizeof(*phy_roothub), GFP_KERNEL);
128 	if (!phy_roothub)
129 		return ERR_PTR(-ENOMEM);
130 
131 	INIT_LIST_HEAD(&phy_roothub->list);
132 
133 	if (!usb_phy_roothub_add_phy_by_name(dev, "usb3-phy", &phy_roothub->list))
134 		return phy_roothub;
135 
136 	return NULL;
137 }
138 EXPORT_SYMBOL_GPL(usb_phy_roothub_alloc_usb3_phy);
139 
140 int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub)
141 {
142 	struct usb_phy_roothub *roothub_entry;
143 	struct list_head *head;
144 	int err;
145 
146 	if (!phy_roothub)
147 		return 0;
148 
149 	head = &phy_roothub->list;
150 
151 	list_for_each_entry(roothub_entry, head, list) {
152 		err = phy_init(roothub_entry->phy);
153 		if (err)
154 			goto err_exit_phys;
155 	}
156 
157 	return 0;
158 
159 err_exit_phys:
160 	list_for_each_entry_continue_reverse(roothub_entry, head, list)
161 		phy_exit(roothub_entry->phy);
162 
163 	return err;
164 }
165 EXPORT_SYMBOL_GPL(usb_phy_roothub_init);
166 
167 int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub)
168 {
169 	struct usb_phy_roothub *roothub_entry;
170 	struct list_head *head;
171 	int err, ret = 0;
172 
173 	if (!phy_roothub)
174 		return 0;
175 
176 	head = &phy_roothub->list;
177 
178 	list_for_each_entry(roothub_entry, head, list) {
179 		err = phy_exit(roothub_entry->phy);
180 		if (err)
181 			ret = err;
182 	}
183 
184 	return ret;
185 }
186 EXPORT_SYMBOL_GPL(usb_phy_roothub_exit);
187 
188 int usb_phy_roothub_set_mode(struct usb_phy_roothub *phy_roothub,
189 			     enum phy_mode mode)
190 {
191 	struct usb_phy_roothub *roothub_entry;
192 	struct list_head *head;
193 	int err;
194 
195 	if (!phy_roothub)
196 		return 0;
197 
198 	head = &phy_roothub->list;
199 
200 	list_for_each_entry(roothub_entry, head, list) {
201 		err = phy_set_mode(roothub_entry->phy, mode);
202 		if (err)
203 			return err;
204 	}
205 
206 	return 0;
207 }
208 EXPORT_SYMBOL_GPL(usb_phy_roothub_set_mode);
209 
210 int usb_phy_roothub_calibrate(struct usb_phy_roothub *phy_roothub)
211 {
212 	struct usb_phy_roothub *roothub_entry;
213 	struct list_head *head;
214 	int err;
215 
216 	if (!phy_roothub)
217 		return 0;
218 
219 	head = &phy_roothub->list;
220 
221 	list_for_each_entry(roothub_entry, head, list) {
222 		err = phy_calibrate(roothub_entry->phy);
223 		if (err)
224 			return err;
225 	}
226 
227 	return 0;
228 }
229 EXPORT_SYMBOL_GPL(usb_phy_roothub_calibrate);
230 
231 /**
232  * usb_phy_roothub_notify_connect() - connect notification
233  * @phy_roothub: the phy of roothub, if the host use a generic phy.
234  * @port: the port index for connect
235  *
236  * If the phy needs to get connection status, the callback can be used.
237  * Returns: %0 if successful, a negative error code otherwise
238  */
239 int usb_phy_roothub_notify_connect(struct usb_phy_roothub *phy_roothub, int port)
240 {
241 	struct usb_phy_roothub *roothub_entry;
242 	struct list_head *head;
243 	int err;
244 
245 	if (!phy_roothub)
246 		return 0;
247 
248 	head = &phy_roothub->list;
249 
250 	list_for_each_entry(roothub_entry, head, list) {
251 		err = phy_notify_connect(roothub_entry->phy, port);
252 		if (err)
253 			return err;
254 	}
255 
256 	return 0;
257 }
258 EXPORT_SYMBOL_GPL(usb_phy_roothub_notify_connect);
259 
260 /**
261  * usb_phy_roothub_notify_disconnect() - disconnect notification
262  * @phy_roothub: the phy of roothub, if the host use a generic phy.
263  * @port: the port index for disconnect
264  *
265  * If the phy needs to get connection status, the callback can be used.
266  * Returns: %0 if successful, a negative error code otherwise
267  */
268 int usb_phy_roothub_notify_disconnect(struct usb_phy_roothub *phy_roothub, int port)
269 {
270 	struct usb_phy_roothub *roothub_entry;
271 	struct list_head *head;
272 	int err;
273 
274 	if (!phy_roothub)
275 		return 0;
276 
277 	head = &phy_roothub->list;
278 
279 	list_for_each_entry(roothub_entry, head, list) {
280 		err = phy_notify_disconnect(roothub_entry->phy, port);
281 		if (err)
282 			return err;
283 	}
284 
285 	return 0;
286 }
287 EXPORT_SYMBOL_GPL(usb_phy_roothub_notify_disconnect);
288 
289 int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub)
290 {
291 	struct usb_phy_roothub *roothub_entry;
292 	struct list_head *head;
293 	int err;
294 
295 	if (!phy_roothub)
296 		return 0;
297 
298 	head = &phy_roothub->list;
299 
300 	list_for_each_entry(roothub_entry, head, list) {
301 		err = phy_power_on(roothub_entry->phy);
302 		if (err)
303 			goto err_out;
304 	}
305 
306 	return 0;
307 
308 err_out:
309 	list_for_each_entry_continue_reverse(roothub_entry, head, list)
310 		phy_power_off(roothub_entry->phy);
311 
312 	return err;
313 }
314 EXPORT_SYMBOL_GPL(usb_phy_roothub_power_on);
315 
316 void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub)
317 {
318 	struct usb_phy_roothub *roothub_entry;
319 
320 	if (!phy_roothub)
321 		return;
322 
323 	list_for_each_entry_reverse(roothub_entry, &phy_roothub->list, list)
324 		phy_power_off(roothub_entry->phy);
325 }
326 EXPORT_SYMBOL_GPL(usb_phy_roothub_power_off);
327 
328 int usb_phy_roothub_suspend(struct device *controller_dev,
329 			    struct usb_phy_roothub *phy_roothub)
330 {
331 	usb_phy_roothub_power_off(phy_roothub);
332 
333 	/* keep the PHYs initialized so the device can wake up the system */
334 	if (device_may_wakeup(controller_dev))
335 		return 0;
336 
337 	return usb_phy_roothub_exit(phy_roothub);
338 }
339 EXPORT_SYMBOL_GPL(usb_phy_roothub_suspend);
340 
341 int usb_phy_roothub_resume(struct device *controller_dev,
342 			   struct usb_phy_roothub *phy_roothub)
343 {
344 	int err;
345 
346 	/* if the device can't wake up the system _exit was called */
347 	if (!device_may_wakeup(controller_dev)) {
348 		err = usb_phy_roothub_init(phy_roothub);
349 		if (err)
350 			return err;
351 	}
352 
353 	err = usb_phy_roothub_power_on(phy_roothub);
354 
355 	/* undo _init if _power_on failed */
356 	if (err && !device_may_wakeup(controller_dev))
357 		usb_phy_roothub_exit(phy_roothub);
358 
359 	return err;
360 }
361 EXPORT_SYMBOL_GPL(usb_phy_roothub_resume);
362