1/* 2 * u_ether.h -- interface to USB gadget "ethernet link" utilities 3 * 4 * Copyright (C) 2003-2005,2008 David Brownell 5 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger 6 * Copyright (C) 2008 Nokia Corporation 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 */ 13 14#ifndef __U_ETHER_H 15#define __U_ETHER_H 16 17#include <linux/err.h> 18#include <linux/if_ether.h> 19#include <linux/usb/composite.h> 20#include <linux/usb/cdc.h> 21 22#include "gadget_chips.h" 23 24 25/* 26 * This represents the USB side of an "ethernet" link, managed by a USB 27 * function which provides control and (maybe) framing. Two functions 28 * in different configurations could share the same ethernet link/netdev, 29 * using different host interaction models. 30 * 31 * There is a current limitation that only one instance of this link may 32 * be present in any given configuration. When that's a problem, network 33 * layer facilities can be used to package multiple logical links on this 34 * single "physical" one. 35 */ 36struct gether { 37 struct usb_function func; 38 39 /* updated by gether_{connect,disconnect} */ 40 struct eth_dev *ioport; 41 42 /* endpoints handle full and/or high speeds */ 43 struct usb_ep *in_ep; 44 struct usb_ep *out_ep; 45 46 bool is_zlp_ok; 47 48 u16 cdc_filter; 49 50 /* hooks for added framing, as needed for RNDIS and EEM. */ 51 u32 header_len; 52 /* NCM requires fixed size bundles */ 53 bool is_fixed; 54 u32 fixed_out_len; 55 u32 fixed_in_len; 56 struct sk_buff *(*wrap)(struct gether *port, 57 struct sk_buff *skb); 58 int (*unwrap)(struct gether *port, 59 struct sk_buff *skb, 60 struct sk_buff_head *list); 61 62 /* called on network open/close */ 63 void (*open)(struct gether *); 64 void (*close)(struct gether *); 65}; 66 67#define DEFAULT_FILTER (USB_CDC_PACKET_TYPE_BROADCAST \ 68 |USB_CDC_PACKET_TYPE_ALL_MULTICAST \ 69 |USB_CDC_PACKET_TYPE_PROMISCUOUS \ 70 |USB_CDC_PACKET_TYPE_DIRECTED) 71 72/* variant of gether_setup that allows customizing network device name */ 73int gether_setup_name(struct usb_gadget *g, u8 ethaddr[ETH_ALEN], 74 const char *netname); 75 76/* netdev setup/teardown as directed by the gadget driver */ 77/* gether_setup - initialize one ethernet-over-usb link 78 * @g: gadget to associated with these links 79 * @ethaddr: NULL, or a buffer in which the ethernet address of the 80 * host side of the link is recorded 81 * Context: may sleep 82 * 83 * This sets up the single network link that may be exported by a 84 * gadget driver using this framework. The link layer addresses are 85 * set up using module parameters. 86 * 87 * Returns negative errno, or zero on success 88 */ 89static inline int gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN]) 90{ 91 return gether_setup_name(g, ethaddr, "usb"); 92} 93 94void gether_cleanup(void); 95 96/* connect/disconnect is handled by individual functions */ 97struct net_device *gether_connect(struct gether *); 98void gether_disconnect(struct gether *); 99 100/* Some controllers can't support CDC Ethernet (ECM) ... */ 101static inline bool can_support_ecm(struct usb_gadget *gadget) 102{ 103 if (!gadget_supports_altsettings(gadget)) 104 return false; 105 106 /* Everything else is *presumably* fine ... but this is a bit 107 * chancy, so be **CERTAIN** there are no hardware issues with 108 * your controller. Add it above if it can't handle CDC. 109 */ 110 return true; 111} 112 113/* each configuration may bind one instance of an ethernet link */ 114int geth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]); 115int ecm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]); 116int ncm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]); 117int eem_bind_config(struct usb_configuration *c); 118 119#ifdef USB_ETH_RNDIS 120 121int rndis_bind_config_vendor(struct usb_configuration *c, u8 ethaddr[ETH_ALEN], 122 u32 vendorID, const char *manufacturer); 123 124#else 125 126static inline int 127rndis_bind_config_vendor(struct usb_configuration *c, u8 ethaddr[ETH_ALEN], 128 u32 vendorID, const char *manufacturer) 129{ 130 return 0; 131} 132 133#endif 134 135/** 136 * rndis_bind_config - add RNDIS network link to a configuration 137 * @c: the configuration to support the network link 138 * @ethaddr: a buffer in which the ethernet address of the host side 139 * side of the link was recorded 140 * Context: single threaded during gadget setup 141 * 142 * Returns zero on success, else negative errno. 143 * 144 * Caller must have called @gether_setup(). Caller is also responsible 145 * for calling @gether_cleanup() before module unload. 146 */ 147static inline int rndis_bind_config(struct usb_configuration *c, 148 u8 ethaddr[ETH_ALEN]) 149{ 150 return rndis_bind_config_vendor(c, ethaddr, 0, NULL); 151} 152 153 154#endif /* __U_ETHER_H */ 155