summaryrefslogtreecommitdiffstats
path: root/drivers/usb/gadget/u_ether.h
blob: 02522338a7081abad0f92c3506a84724f61df23b (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
/*
 * u_ether.h -- interface to USB gadget "ethernet link" utilities
 *
 * Copyright (C) 2003-2005,2008 David Brownell
 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
 * Copyright (C) 2008 Nokia Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#ifndef __U_ETHER_H
#define __U_ETHER_H

#include <linux/err.h>
#include <linux/if_ether.h>
#include <linux/usb/composite.h>
#include <linux/usb/cdc.h>

#include "gadget_chips.h"

struct eth_dev;

/*
 * This represents the USB side of an "ethernet" link, managed by a USB
 * function which provides control and (maybe) framing.  Two functions
 * in different configurations could share the same ethernet link/netdev,
 * using different host interaction models.
 *
 * There is a current limitation that only one instance of this link may
 * be present in any given configuration.  When that's a problem, network
 * layer facilities can be used to package multiple logical links on this
 * single "physical" one.
 */
struct gether {
	struct usb_function		func;

	/* updated by gether_{connect,disconnect} */
	struct eth_dev			*ioport;

	/* endpoints handle full and/or high speeds */
	struct usb_ep			*in_ep;
	struct usb_ep			*out_ep;

	bool				is_zlp_ok;

	u16				cdc_filter;

	/* hooks for added framing, as needed for RNDIS and EEM. */
	u32				header_len;
	/* NCM requires fixed size bundles */
	bool				is_fixed;
	u32				fixed_out_len;
	u32				fixed_in_len;
	struct sk_buff			*(*wrap)(struct gether *port,
						struct sk_buff *skb);
	int				(*unwrap)(struct gether *port,
						struct sk_buff *skb,
						struct sk_buff_head *list);

	/* called on network open/close */
	void				(*open)(struct gether *);
	void				(*close)(struct gether *);
};

#define	DEFAULT_FILTER	(USB_CDC_PACKET_TYPE_BROADCAST \
			|USB_CDC_PACKET_TYPE_ALL_MULTICAST \
			|USB_CDC_PACKET_TYPE_PROMISCUOUS \
			|USB_CDC_PACKET_TYPE_DIRECTED)

/* variant of gether_setup that allows customizing network device name */
struct eth_dev *gether_setup_name(struct usb_gadget *g, u8 ethaddr[ETH_ALEN],
		const char *netname);

/* netdev setup/teardown as directed by the gadget driver */
/* gether_setup - initialize one ethernet-over-usb link
 * @g: gadget to associated with these links
 * @ethaddr: NULL, or a buffer in which the ethernet address of the
 *	host side of the link is recorded
 * Context: may sleep
 *
 * This sets up the single network link that may be exported by a
 * gadget driver using this framework.  The link layer addresses are
 * set up using module parameters.
 *
 * Returns negative errno, or zero on success
 */
static inline struct eth_dev *gether_setup(struct usb_gadget *g,
		u8 ethaddr[ETH_ALEN])
{
	return gether_setup_name(g, ethaddr, "usb");
}

void gether_cleanup(struct eth_dev *dev);

/* connect/disconnect is handled by individual functions */
struct net_device *gether_connect(struct gether *);
void gether_disconnect(struct gether *);

/* Some controllers can't support CDC Ethernet (ECM) ... */
static inline bool can_support_ecm(struct usb_gadget *gadget)
{
	if (!gadget_supports_altsettings(gadget))
		return false;

	/* Everything else is *presumably* fine ... but this is a bit
	 * chancy, so be **CERTAIN** there are no hardware issues with
	 * your controller.  Add it above if it can't handle CDC.
	 */
	return true;
}

/* each configuration may bind one instance of an ethernet link */
int geth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
		struct eth_dev *dev);
int ecm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
		struct eth_dev *dev);
int ncm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
		struct eth_dev *dev);
int eem_bind_config(struct usb_configuration *c, struct eth_dev *dev);

#ifdef USB_ETH_RNDIS

int rndis_bind_config_vendor(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
		u32 vendorID, const char *manufacturer, struct eth_dev *dev);

#else

static inline int
rndis_bind_config_vendor(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
		u32 vendorID, const char *manufacturer, struct eth_dev *dev)
{
	return 0;
}

#endif

/**
 * rndis_bind_config - add RNDIS network link to a configuration
 * @c: the configuration to support the network link
 * @ethaddr: a buffer in which the ethernet address of the host side
 *	side of the link was recorded
 * Context: single threaded during gadget setup
 *
 * Returns zero on success, else negative errno.
 *
 * Caller must have called @gether_setup().  Caller is also responsible
 * for calling @gether_cleanup() before module unload.
 */
static inline int rndis_bind_config(struct usb_configuration *c,
		u8 ethaddr[ETH_ALEN], struct eth_dev *dev)
{
	return rndis_bind_config_vendor(c, ethaddr, 0, NULL, dev);
}


#endif /* __U_ETHER_H */