1// SPDX-License-Identifier: GPL-2.0
2
3#ifndef __LINUX_USB_ROLE_H
4#define __LINUX_USB_ROLE_H
5
6#include <linux/device.h>
7
8struct usb_role_switch;
9
10enum usb_role {
11 USB_ROLE_NONE,
12 USB_ROLE_HOST,
13 USB_ROLE_DEVICE,
14};
15
16typedef int (*usb_role_switch_set_t)(struct usb_role_switch *sw,
17 enum usb_role role);
18typedef enum usb_role (*usb_role_switch_get_t)(struct usb_role_switch *sw);
19
20/**
21 * struct usb_role_switch_desc - USB Role Switch Descriptor
22 * @fwnode: The device node to be associated with the role switch
23 * @usb2_port: Optional reference to the host controller port device (USB2)
24 * @usb3_port: Optional reference to the host controller port device (USB3)
25 * @udc: Optional reference to the peripheral controller device
26 * @set: Callback for setting the role
27 * @get: Callback for getting the role (optional)
28 * @allow_userspace_control: If true userspace may change the role through sysfs
29 * @driver_data: Private data pointer
30 * @name: Name for the switch (optional)
31 *
32 * @usb2_port and @usb3_port will point to the USB host port and @udc to the USB
33 * device controller behind the USB connector with the role switch. If
34 * @usb2_port, @usb3_port and @udc are included in the description, the
35 * reference count for them should be incremented by the caller of
36 * usb_role_switch_register() before registering the switch.
37 */
38struct usb_role_switch_desc {
39 struct fwnode_handle *fwnode;
40 struct device *usb2_port;
41 struct device *usb3_port;
42 struct device *udc;
43 usb_role_switch_set_t set;
44 usb_role_switch_get_t get;
45 bool allow_userspace_control;
46 void *driver_data;
47 const char *name;
48};
49
50
51#if IS_ENABLED(CONFIG_USB_ROLE_SWITCH)
52int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role);
53enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw);
54struct usb_role_switch *usb_role_switch_get(struct device *dev);
55struct usb_role_switch *fwnode_usb_role_switch_get(struct fwnode_handle *node);
56void usb_role_switch_put(struct usb_role_switch *sw);
57
58struct usb_role_switch *
59usb_role_switch_find_by_fwnode(const struct fwnode_handle *fwnode);
60
61struct usb_role_switch *
62usb_role_switch_register(struct device *parent,
63 const struct usb_role_switch_desc *desc);
64void usb_role_switch_unregister(struct usb_role_switch *sw);
65
66void usb_role_switch_set_drvdata(struct usb_role_switch *sw, void *data);
67void *usb_role_switch_get_drvdata(struct usb_role_switch *sw);
68const char *usb_role_string(enum usb_role role);
69#else
70static inline int usb_role_switch_set_role(struct usb_role_switch *sw,
71 enum usb_role role)
72{
73 return 0;
74}
75
76static inline enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw)
77{
78 return USB_ROLE_NONE;
79}
80
81static inline struct usb_role_switch *usb_role_switch_get(struct device *dev)
82{
83 return ERR_PTR(-ENODEV);
84}
85
86static inline struct usb_role_switch *
87fwnode_usb_role_switch_get(struct fwnode_handle *node)
88{
89 return ERR_PTR(-ENODEV);
90}
91
92static inline void usb_role_switch_put(struct usb_role_switch *sw) { }
93
94static inline struct usb_role_switch *
95usb_role_switch_find_by_fwnode(const struct fwnode_handle *fwnode)
96{
97 return NULL;
98}
99
100static inline struct usb_role_switch *
101usb_role_switch_register(struct device *parent,
102 const struct usb_role_switch_desc *desc)
103{
104 return ERR_PTR(-ENODEV);
105}
106
107static inline void usb_role_switch_unregister(struct usb_role_switch *sw) { }
108
109static inline void
110usb_role_switch_set_drvdata(struct usb_role_switch *sw, void *data)
111{
112}
113
114static inline void *usb_role_switch_get_drvdata(struct usb_role_switch *sw)
115{
116 return NULL;
117}
118
119static inline const char *usb_role_string(enum usb_role role)
120{
121 return "unknown";
122}
123
124#endif
125
126#endif /* __LINUX_USB_ROLE_H */
127

source code of linux/include/linux/usb/role.h