1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * u_ether.h -- interface to USB gadget "ethernet link" utilities 4 * 5 * Copyright (C) 2003-2005,2008 David Brownell 6 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger 7 * Copyright (C) 2008 Nokia Corporation 8 */ 9 10 #ifndef __U_ETHER_H 11 #define __U_ETHER_H 12 13 #include <linux/err.h> 14 #include <linux/if_ether.h> 15 #include <linux/usb/composite.h> 16 #include <linux/usb/cdc.h> 17 #include <linux/netdevice.h> 18 19 #define QMULT_DEFAULT 5 20 21 /* 22 * dev_addr: initial value 23 * changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx" 24 * host_addr: this address is invisible to ifconfig 25 */ 26 #define USB_ETHERNET_MODULE_PARAMETERS() \ 27 static unsigned qmult = QMULT_DEFAULT; \ 28 module_param(qmult, uint, S_IRUGO|S_IWUSR); \ 29 MODULE_PARM_DESC(qmult, "queue length multiplier at high/super speed");\ 30 \ 31 static char *dev_addr; \ 32 module_param(dev_addr, charp, S_IRUGO); \ 33 MODULE_PARM_DESC(dev_addr, "Device Ethernet Address"); \ 34 \ 35 static char *host_addr; \ 36 module_param(host_addr, charp, S_IRUGO); \ 37 MODULE_PARM_DESC(host_addr, "Host Ethernet Address") 38 39 struct eth_dev; 40 41 /* 42 * This represents the USB side of an "ethernet" link, managed by a USB 43 * function which provides control and (maybe) framing. Two functions 44 * in different configurations could share the same ethernet link/netdev, 45 * using different host interaction models. 46 * 47 * There is a current limitation that only one instance of this link may 48 * be present in any given configuration. When that's a problem, network 49 * layer facilities can be used to package multiple logical links on this 50 * single "physical" one. 51 */ 52 struct gether { 53 struct usb_function func; 54 55 /* updated by gether_{connect,disconnect} */ 56 struct eth_dev *ioport; 57 58 /* endpoints handle full and/or high speeds */ 59 struct usb_ep *in_ep; 60 struct usb_ep *out_ep; 61 62 bool is_zlp_ok; 63 64 u16 cdc_filter; 65 66 /* hooks for added framing, as needed for RNDIS and EEM. */ 67 u32 header_len; 68 /* NCM requires fixed size bundles */ 69 bool is_fixed; 70 u32 fixed_out_len; 71 u32 fixed_in_len; 72 bool supports_multi_frame; 73 struct sk_buff *(*wrap)(struct gether *port, 74 struct sk_buff *skb); 75 int (*unwrap)(struct gether *port, 76 struct sk_buff *skb, 77 struct sk_buff_head *list); 78 79 /* called on network open/close */ 80 void (*open)(struct gether *); 81 void (*close)(struct gether *); 82 bool is_suspend; 83 }; 84 85 #define DEFAULT_FILTER (USB_CDC_PACKET_TYPE_BROADCAST \ 86 |USB_CDC_PACKET_TYPE_ALL_MULTICAST \ 87 |USB_CDC_PACKET_TYPE_PROMISCUOUS \ 88 |USB_CDC_PACKET_TYPE_DIRECTED) 89 90 /* variant of gether_setup that allows customizing network device name */ 91 struct eth_dev *gether_setup_name(struct usb_gadget *g, 92 const char *dev_addr, const char *host_addr, 93 u8 ethaddr[ETH_ALEN], unsigned qmult, const char *netname); 94 95 /* netdev setup/teardown as directed by the gadget driver */ 96 /* gether_setup - initialize one ethernet-over-usb link 97 * @g: gadget to associated with these links 98 * @ethaddr: NULL, or a buffer in which the ethernet address of the 99 * host side of the link is recorded 100 * Context: may sleep 101 * 102 * This sets up the single network link that may be exported by a 103 * gadget driver using this framework. The link layer addresses are 104 * set up using module parameters. 105 * 106 * Returns a eth_dev pointer on success, or an ERR_PTR on failure 107 */ 108 static inline struct eth_dev *gether_setup(struct usb_gadget *g, 109 const char *dev_addr, const char *host_addr, 110 u8 ethaddr[ETH_ALEN], unsigned qmult) 111 { 112 return gether_setup_name(g, dev_addr, host_addr, ethaddr, qmult, "usb"); 113 } 114 115 /* 116 * variant of gether_setup_default that allows customizing 117 * network device name 118 */ 119 struct net_device *gether_setup_name_default(const char *netname); 120 121 /* 122 * gether_register_netdev - register the net device 123 * @net: net device to register 124 * 125 * Registers the net device associated with this ethernet-over-usb link 126 * 127 */ 128 int gether_register_netdev(struct net_device *net); 129 130 /* gether_setup_default - initialize one ethernet-over-usb link 131 * Context: may sleep 132 * 133 * This sets up the single network link that may be exported by a 134 * gadget driver using this framework. The link layer addresses 135 * are set to random values. 136 * 137 * Returns negative errno, or zero on success 138 */ 139 static inline struct net_device *gether_setup_default(void) 140 { 141 return gether_setup_name_default("usb"); 142 } 143 144 /** 145 * gether_set_gadget - initialize one ethernet-over-usb link with a gadget 146 * @net: device representing this link 147 * @g: the gadget to initialize with 148 * 149 * This associates one ethernet-over-usb link with a gadget. 150 */ 151 void gether_set_gadget(struct net_device *net, struct usb_gadget *g); 152 153 /** 154 * gether_set_dev_addr - initialize an ethernet-over-usb link with eth address 155 * @net: device representing this link 156 * @dev_addr: eth address of this device 157 * 158 * This sets the device-side Ethernet address of this ethernet-over-usb link 159 * if dev_addr is correct. 160 * Returns negative errno if the new address is incorrect. 161 */ 162 int gether_set_dev_addr(struct net_device *net, const char *dev_addr); 163 164 /** 165 * gether_get_dev_addr - get an ethernet-over-usb link eth address 166 * @net: device representing this link 167 * @dev_addr: place to store device's eth address 168 * @len: length of the @dev_addr buffer 169 * 170 * This gets the device-side Ethernet address of this ethernet-over-usb link. 171 * Returns zero on success, else negative errno. 172 */ 173 int gether_get_dev_addr(struct net_device *net, char *dev_addr, int len); 174 175 /** 176 * gether_set_host_addr - initialize an ethernet-over-usb link with host address 177 * @net: device representing this link 178 * @host_addr: eth address of the host 179 * 180 * This sets the host-side Ethernet address of this ethernet-over-usb link 181 * if host_addr is correct. 182 * Returns negative errno if the new address is incorrect. 183 */ 184 int gether_set_host_addr(struct net_device *net, const char *host_addr); 185 186 /** 187 * gether_get_host_addr - get an ethernet-over-usb link host address 188 * @net: device representing this link 189 * @host_addr: place to store eth address of the host 190 * @len: length of the @host_addr buffer 191 * 192 * This gets the host-side Ethernet address of this ethernet-over-usb link. 193 * Returns zero on success, else negative errno. 194 */ 195 int gether_get_host_addr(struct net_device *net, char *host_addr, int len); 196 197 /** 198 * gether_get_host_addr_cdc - get an ethernet-over-usb link host address 199 * @net: device representing this link 200 * @host_addr: place to store eth address of the host 201 * @len: length of the @host_addr buffer 202 * 203 * This gets the CDC formatted host-side Ethernet address of this 204 * ethernet-over-usb link. 205 * Returns zero on success, else negative errno. 206 */ 207 int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len); 208 209 /** 210 * gether_get_host_addr_u8 - get an ethernet-over-usb link host address 211 * @net: device representing this link 212 * @host_mac: place to store the eth address of the host 213 * 214 * This gets the binary formatted host-side Ethernet address of this 215 * ethernet-over-usb link. 216 */ 217 void gether_get_host_addr_u8(struct net_device *net, u8 host_mac[ETH_ALEN]); 218 219 /** 220 * gether_set_qmult - initialize an ethernet-over-usb link with a multiplier 221 * @net: device representing this link 222 * @qmult: queue multiplier 223 * 224 * This sets the queue length multiplier of this ethernet-over-usb link. 225 * For higher speeds use longer queues. 226 */ 227 void gether_set_qmult(struct net_device *net, unsigned qmult); 228 229 /** 230 * gether_get_qmult - get an ethernet-over-usb link multiplier 231 * @net: device representing this link 232 * 233 * This gets the queue length multiplier of this ethernet-over-usb link. 234 */ 235 unsigned gether_get_qmult(struct net_device *net); 236 237 /** 238 * gether_get_ifname - get an ethernet-over-usb link interface name 239 * @net: device representing this link 240 * @name: place to store the interface name 241 * @len: length of the @name buffer 242 * 243 * This gets the interface name of this ethernet-over-usb link. 244 * Returns zero on success, else negative errno. 245 */ 246 int gether_get_ifname(struct net_device *net, char *name, int len); 247 248 /** 249 * gether_set_ifname - set an ethernet-over-usb link interface name 250 * @net: device representing this link 251 * @name: new interface name 252 * @len: length of @name 253 * 254 * This sets the interface name of this ethernet-over-usb link. 255 * A single terminating newline, if any, is ignored. 256 * Returns zero on success, else negative errno. 257 */ 258 int gether_set_ifname(struct net_device *net, const char *name, int len); 259 260 void gether_cleanup(struct eth_dev *dev); 261 262 void gether_suspend(struct gether *link); 263 void gether_resume(struct gether *link); 264 265 /* connect/disconnect is handled by individual functions */ 266 struct net_device *gether_connect(struct gether *); 267 void gether_disconnect(struct gether *); 268 269 /* Some controllers can't support CDC Ethernet (ECM) ... */ 270 static inline bool can_support_ecm(struct usb_gadget *gadget) 271 { 272 if (!gadget_is_altset_supported(gadget)) 273 return false; 274 275 /* Everything else is *presumably* fine ... but this is a bit 276 * chancy, so be **CERTAIN** there are no hardware issues with 277 * your controller. Add it above if it can't handle CDC. 278 */ 279 return true; 280 } 281 282 #endif /* __U_ETHER_H */ 283