xref: /linux-6.15/include/uapi/linux/usb/raw_gadget.h (revision 82d00a93)
1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3  * USB Raw Gadget driver.
4  *
5  * See Documentation/usb/raw-gadget.rst for more details.
6  */
7 
8 #ifndef _UAPI__LINUX_USB_RAW_GADGET_H
9 #define _UAPI__LINUX_USB_RAW_GADGET_H
10 
11 #include <asm/ioctl.h>
12 #include <linux/types.h>
13 #include <linux/usb/ch9.h>
14 
15 /* Maximum length of driver_name/device_name in the usb_raw_init struct. */
16 #define UDC_NAME_LENGTH_MAX 128
17 
18 /*
19  * struct usb_raw_init - argument for USB_RAW_IOCTL_INIT ioctl.
20  * @speed: The speed of the emulated USB device, takes the same values as
21  *     the usb_device_speed enum: USB_SPEED_FULL, USB_SPEED_HIGH, etc.
22  * @driver_name: The name of the UDC driver.
23  * @device_name: The name of a UDC instance.
24  *
25  * The last two fields identify a UDC the gadget driver should bind to.
26  * For example, Dummy UDC has "dummy_udc" as its driver_name and "dummy_udc.N"
27  * as its device_name, where N in the index of the Dummy UDC instance.
28  * At the same time the dwc2 driver that is used on Raspberry Pi Zero, has
29  * "20980000.usb" as both driver_name and device_name.
30  */
31 struct usb_raw_init {
32 	__u8	driver_name[UDC_NAME_LENGTH_MAX];
33 	__u8	device_name[UDC_NAME_LENGTH_MAX];
34 	__u8	speed;
35 };
36 
37 /* The type of event fetched with the USB_RAW_IOCTL_EVENT_FETCH ioctl. */
38 enum usb_raw_event_type {
39 	USB_RAW_EVENT_INVALID = 0,
40 
41 	/* This event is queued when the driver has bound to a UDC. */
42 	USB_RAW_EVENT_CONNECT = 1,
43 
44 	/* This event is queued when a new control request arrived to ep0. */
45 	USB_RAW_EVENT_CONTROL = 2,
46 
47 	/* The list might grow in the future. */
48 };
49 
50 /*
51  * struct usb_raw_event - argument for USB_RAW_IOCTL_EVENT_FETCH ioctl.
52  * @type: The type of the fetched event.
53  * @length: Length of the data buffer. Updated by the driver and set to the
54  *     actual length of the fetched event data.
55  * @data: A buffer to store the fetched event data.
56  *
57  * Currently the fetched data buffer is empty for USB_RAW_EVENT_CONNECT,
58  * and contains struct usb_ctrlrequest for USB_RAW_EVENT_CONTROL.
59  */
60 struct usb_raw_event {
61 	__u32		type;
62 	__u32		length;
63 	__u8		data[0];
64 };
65 
66 #define USB_RAW_IO_FLAGS_ZERO	0x0001
67 #define USB_RAW_IO_FLAGS_MASK	0x0001
68 
69 static inline int usb_raw_io_flags_valid(__u16 flags)
70 {
71 	return (flags & ~USB_RAW_IO_FLAGS_MASK) == 0;
72 }
73 
74 static inline int usb_raw_io_flags_zero(__u16 flags)
75 {
76 	return (flags & USB_RAW_IO_FLAGS_ZERO);
77 }
78 
79 /*
80  * struct usb_raw_ep_io - argument for USB_RAW_IOCTL_EP0/EP_WRITE/READ ioctls.
81  * @ep: Endpoint handle as returned by USB_RAW_IOCTL_EP_ENABLE for
82  *     USB_RAW_IOCTL_EP_WRITE/READ. Ignored for USB_RAW_IOCTL_EP0_WRITE/READ.
83  * @flags: When USB_RAW_IO_FLAGS_ZERO is specified, the zero flag is set on
84  *     the submitted USB request, see include/linux/usb/gadget.h for details.
85  * @length: Length of data.
86  * @data: Data to send for USB_RAW_IOCTL_EP0/EP_WRITE. Buffer to store received
87  *     data for USB_RAW_IOCTL_EP0/EP_READ.
88  */
89 struct usb_raw_ep_io {
90 	__u16		ep;
91 	__u16		flags;
92 	__u32		length;
93 	__u8		data[0];
94 };
95 
96 /*
97  * Initializes a Raw Gadget instance.
98  * Accepts a pointer to the usb_raw_init struct as an argument.
99  * Returns 0 on success or negative error code on failure.
100  */
101 #define USB_RAW_IOCTL_INIT		_IOW('U', 0, struct usb_raw_init)
102 
103 /*
104  * Instructs Raw Gadget to bind to a UDC and start emulating a USB device.
105  * Returns 0 on success or negative error code on failure.
106  */
107 #define USB_RAW_IOCTL_RUN		_IO('U', 1)
108 
109 /*
110  * A blocking ioctl that waits for an event and returns fetched event data to
111  * the user.
112  * Accepts a pointer to the usb_raw_event struct.
113  * Returns 0 on success or negative error code on failure.
114  */
115 #define USB_RAW_IOCTL_EVENT_FETCH	_IOR('U', 2, struct usb_raw_event)
116 
117 /*
118  * Queues an IN (OUT for READ) urb as a response to the last control request
119  * received on endpoint 0, provided that was an IN (OUT for READ) request and
120  * waits until the urb is completed. Copies received data to user for READ.
121  * Accepts a pointer to the usb_raw_ep_io struct as an argument.
122  * Returns length of trasferred data on success or negative error code on
123  * failure.
124  */
125 #define USB_RAW_IOCTL_EP0_WRITE		_IOW('U', 3, struct usb_raw_ep_io)
126 #define USB_RAW_IOCTL_EP0_READ		_IOWR('U', 4, struct usb_raw_ep_io)
127 
128 /*
129  * Finds an endpoint that supports the transfer type specified in the
130  * descriptor and enables it.
131  * Accepts a pointer to the usb_endpoint_descriptor struct as an argument.
132  * Returns enabled endpoint handle on success or negative error code on failure.
133  */
134 #define USB_RAW_IOCTL_EP_ENABLE		_IOW('U', 5, struct usb_endpoint_descriptor)
135 
136 /* Disables specified endpoint.
137  * Accepts endpoint handle as an argument.
138  * Returns 0 on success or negative error code on failure.
139  */
140 #define USB_RAW_IOCTL_EP_DISABLE	_IOW('U', 6, __u32)
141 
142 /*
143  * Queues an IN (OUT for READ) urb as a response to the last control request
144  * received on endpoint usb_raw_ep_io.ep, provided that was an IN (OUT for READ)
145  * request and waits until the urb is completed. Copies received data to user
146  * for READ.
147  * Accepts a pointer to the usb_raw_ep_io struct as an argument.
148  * Returns length of trasferred data on success or negative error code on
149  * failure.
150  */
151 #define USB_RAW_IOCTL_EP_WRITE		_IOW('U', 7, struct usb_raw_ep_io)
152 #define USB_RAW_IOCTL_EP_READ		_IOWR('U', 8, struct usb_raw_ep_io)
153 
154 /*
155  * Switches the gadget into the configured state.
156  * Returns 0 on success or negative error code on failure.
157  */
158 #define USB_RAW_IOCTL_CONFIGURE		_IO('U', 9)
159 
160 /*
161  * Constrains UDC VBUS power usage.
162  * Accepts current limit in 2 mA units as an argument.
163  * Returns 0 on success or negative error code on failure.
164  */
165 #define USB_RAW_IOCTL_VBUS_DRAW		_IOW('U', 10, __u32)
166 
167 #endif /* _UAPI__LINUX_USB_RAW_GADGET_H */
168