xref: /linux/drivers/usb/core/phy.c (revision a4a755c422242c27cb0f7900ac00cf33ac17b1ce)
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 			goto err_out;
204 	}
205 
206 	return 0;
207 
208 err_out:
209 	list_for_each_entry_continue_reverse(roothub_entry, head, list)
210 		phy_power_off(roothub_entry->phy);
211 
212 	return err;
213 }
214 EXPORT_SYMBOL_GPL(usb_phy_roothub_set_mode);
215 
216 int usb_phy_roothub_calibrate(struct usb_phy_roothub *phy_roothub)
217 {
218 	struct usb_phy_roothub *roothub_entry;
219 	struct list_head *head;
220 	int err;
221 
222 	if (!phy_roothub)
223 		return 0;
224 
225 	head = &phy_roothub->list;
226 
227 	list_for_each_entry(roothub_entry, head, list) {
228 		err = phy_calibrate(roothub_entry->phy);
229 		if (err)
230 			return err;
231 	}
232 
233 	return 0;
234 }
235 EXPORT_SYMBOL_GPL(usb_phy_roothub_calibrate);
236 
237 /**
238  * usb_phy_roothub_notify_connect() - connect notification
239  * @phy_roothub: the phy of roothub, if the host use a generic phy.
240  * @port: the port index for connect
241  *
242  * If the phy needs to get connection status, the callback can be used.
243  * Returns: %0 if successful, a negative error code otherwise
244  */
245 int usb_phy_roothub_notify_connect(struct usb_phy_roothub *phy_roothub, int port)
246 {
247 	struct usb_phy_roothub *roothub_entry;
248 	struct list_head *head;
249 	int err;
250 
251 	if (!phy_roothub)
252 		return 0;
253 
254 	head = &phy_roothub->list;
255 
256 	list_for_each_entry(roothub_entry, head, list) {
257 		err = phy_notify_connect(roothub_entry->phy, port);
258 		if (err)
259 			return err;
260 	}
261 
262 	return 0;
263 }
264 EXPORT_SYMBOL_GPL(usb_phy_roothub_notify_connect);
265 
266 /**
267  * usb_phy_roothub_notify_disconnect() - disconnect notification
268  * @phy_roothub: the phy of roothub, if the host use a generic phy.
269  * @port: the port index for disconnect
270  *
271  * If the phy needs to get connection status, the callback can be used.
272  * Returns: %0 if successful, a negative error code otherwise
273  */
274 int usb_phy_roothub_notify_disconnect(struct usb_phy_roothub *phy_roothub, int port)
275 {
276 	struct usb_phy_roothub *roothub_entry;
277 	struct list_head *head;
278 	int err;
279 
280 	if (!phy_roothub)
281 		return 0;
282 
283 	head = &phy_roothub->list;
284 
285 	list_for_each_entry(roothub_entry, head, list) {
286 		err = phy_notify_disconnect(roothub_entry->phy, port);
287 		if (err)
288 			return err;
289 	}
290 
291 	return 0;
292 }
293 EXPORT_SYMBOL_GPL(usb_phy_roothub_notify_disconnect);
294 
295 int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub)
296 {
297 	struct usb_phy_roothub *roothub_entry;
298 	struct list_head *head;
299 	int err;
300 
301 	if (!phy_roothub)
302 		return 0;
303 
304 	head = &phy_roothub->list;
305 
306 	list_for_each_entry(roothub_entry, head, list) {
307 		err = phy_power_on(roothub_entry->phy);
308 		if (err)
309 			goto err_out;
310 	}
311 
312 	return 0;
313 
314 err_out:
315 	list_for_each_entry_continue_reverse(roothub_entry, head, list)
316 		phy_power_off(roothub_entry->phy);
317 
318 	return err;
319 }
320 EXPORT_SYMBOL_GPL(usb_phy_roothub_power_on);
321 
322 void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub)
323 {
324 	struct usb_phy_roothub *roothub_entry;
325 
326 	if (!phy_roothub)
327 		return;
328 
329 	list_for_each_entry_reverse(roothub_entry, &phy_roothub->list, list)
330 		phy_power_off(roothub_entry->phy);
331 }
332 EXPORT_SYMBOL_GPL(usb_phy_roothub_power_off);
333 
334 int usb_phy_roothub_suspend(struct device *controller_dev,
335 			    struct usb_phy_roothub *phy_roothub)
336 {
337 	usb_phy_roothub_power_off(phy_roothub);
338 
339 	/* keep the PHYs initialized so the device can wake up the system */
340 	if (device_may_wakeup(controller_dev))
341 		return 0;
342 
343 	return usb_phy_roothub_exit(phy_roothub);
344 }
345 EXPORT_SYMBOL_GPL(usb_phy_roothub_suspend);
346 
347 int usb_phy_roothub_resume(struct device *controller_dev,
348 			   struct usb_phy_roothub *phy_roothub)
349 {
350 	int err;
351 
352 	/* if the device can't wake up the system _exit was called */
353 	if (!device_may_wakeup(controller_dev)) {
354 		err = usb_phy_roothub_init(phy_roothub);
355 		if (err)
356 			return err;
357 	}
358 
359 	err = usb_phy_roothub_power_on(phy_roothub);
360 
361 	/* undo _init if _power_on failed */
362 	if (err && !device_may_wakeup(controller_dev))
363 		usb_phy_roothub_exit(phy_roothub);
364 
365 	return err;
366 }
367 EXPORT_SYMBOL_GPL(usb_phy_roothub_resume);
368