summaryrefslogtreecommitdiffstats
path: root/drivers/usb/core/phy.c
blob: 9879767452a23e6a0c1ceeea65cfc0b8874fa65a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
// SPDX-License-Identifier: GPL-2.0+
/*
 * A wrapper for multiple PHYs which passes all phy_* function calls to
 * multiple (actual) PHY devices. This is comes handy when initializing
 * all PHYs on a HCD and to keep them all in the same state.
 *
 * Copyright (C) 2018 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
 */

#include <linux/device.h>
#include <linux/list.h>
#include <linux/phy/phy.h>
#include <linux/of.h>

#include "phy.h"

struct usb_phy_roothub {
	struct phy		*phy;
	struct list_head	list;
};

static int usb_phy_roothub_add_phy(struct device *dev, int index,
				   struct list_head *list)
{
	struct usb_phy_roothub *roothub_entry;
	struct phy *phy = devm_of_phy_get_by_index(dev, dev->of_node, index);

	if (IS_ERR_OR_NULL(phy)) {
		if (!phy || PTR_ERR(phy) == -ENODEV)
			return 0;
		else
			return PTR_ERR(phy);
	}

	roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL);
	if (!roothub_entry)
		return -ENOMEM;

	INIT_LIST_HEAD(&roothub_entry->list);

	roothub_entry->phy = phy;

	list_add_tail(&roothub_entry->list, list);

	return 0;
}

struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev)
{
	struct usb_phy_roothub *phy_roothub;
	int i, num_phys, err;

	if (!IS_ENABLED(CONFIG_GENERIC_PHY))
		return NULL;

	num_phys = of_count_phandle_with_args(dev->of_node, "phys",
					      "#phy-cells");
	if (num_phys <= 0)
		return NULL;

	phy_roothub = devm_kzalloc(dev, sizeof(*phy_roothub), GFP_KERNEL);
	if (!phy_roothub)
		return ERR_PTR(-ENOMEM);

	INIT_LIST_HEAD(&phy_roothub->list);

	for (i = 0; i < num_phys; i++) {
		err = usb_phy_roothub_add_phy(dev, i, &phy_roothub->list);
		if (err)
			return ERR_PTR(err);
	}

	return phy_roothub;
}
EXPORT_SYMBOL_GPL(usb_phy_roothub_alloc);

int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub)
{
	struct usb_phy_roothub *roothub_entry;
	struct list_head *head;
	int err;

	if (!phy_roothub)
		return 0;

	head = &phy_roothub->list;

	list_for_each_entry(roothub_entry, head, list) {
		err = phy_init(roothub_entry->phy);
		if (err)
			goto err_exit_phys;
	}

	return 0;

err_exit_phys:
	list_for_each_entry_continue_reverse(roothub_entry, head, list)
		phy_exit(roothub_entry->phy);

	return err;
}
EXPORT_SYMBOL_GPL(usb_phy_roothub_init);

int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub)
{
	struct usb_phy_roothub *roothub_entry;
	struct list_head *head;
	int err, ret = 0;

	if (!phy_roothub)
		return 0;

	head = &phy_roothub->list;

	list_for_each_entry(roothub_entry, head, list) {
		err = phy_exit(roothub_entry->phy);
		if (err)
			ret = err;
	}

	return ret;
}
EXPORT_SYMBOL_GPL(usb_phy_roothub_exit);

int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub)
{
	struct usb_phy_roothub *roothub_entry;
	struct list_head *head;
	int err;

	if (!phy_roothub)
		return 0;

	head = &phy_roothub->list;

	list_for_each_entry(roothub_entry, head, list) {
		err = phy_power_on(roothub_entry->phy);
		if (err)
			goto err_out;
	}

	return 0;

err_out:
	list_for_each_entry_continue_reverse(roothub_entry, head, list)
		phy_power_off(roothub_entry->phy);

	return err;
}
EXPORT_SYMBOL_GPL(usb_phy_roothub_power_on);

void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub)
{
	struct usb_phy_roothub *roothub_entry;

	if (!phy_roothub)
		return;

	list_for_each_entry_reverse(roothub_entry, &phy_roothub->list, list)
		phy_power_off(roothub_entry->phy);
}
EXPORT_SYMBOL_GPL(usb_phy_roothub_power_off);

int usb_phy_roothub_suspend(struct device *controller_dev,
			    struct usb_phy_roothub *phy_roothub)
{
	usb_phy_roothub_power_off(phy_roothub);

	/* keep the PHYs initialized so the device can wake up the system */
	if (device_may_wakeup(controller_dev))
		return 0;

	return usb_phy_roothub_exit(phy_roothub);
}
EXPORT_SYMBOL_GPL(usb_phy_roothub_suspend);

int usb_phy_roothub_resume(struct device *controller_dev,
			   struct usb_phy_roothub *phy_roothub)
{
	int err;

	/* if the device can't wake up the system _exit was called */
	if (!device_may_wakeup(controller_dev)) {
		err = usb_phy_roothub_init(phy_roothub);
		if (err)
			return err;
	}

	err = usb_phy_roothub_power_on(phy_roothub);

	/* undo _init if _power_on failed */
	if (err && !device_may_wakeup(controller_dev))
		usb_phy_roothub_exit(phy_roothub);

	return err;
}
EXPORT_SYMBOL_GPL(usb_phy_roothub_resume);
OpenPOWER on IntegriCloud