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_attach_gadget - Reparent net_device to the gadget device. 155 * @net: The network device to reparent. 156 * @g: The target USB gadget device to parent to. 157 * 158 * This function moves the network device to be a child of the USB gadget 159 * device in the device hierarchy. This is typically done when the function 160 * is bound to a configuration. 161 * 162 * Returns 0 on success, or a negative error code on failure. 163 */ 164 int gether_attach_gadget(struct net_device *net, struct usb_gadget *g); 165 166 /** 167 * gether_detach_gadget - Detach net_device from its gadget parent. 168 * @net: The network device to detach. 169 * 170 * This function moves the network device to be a child of the virtual 171 * devices parent, effectively detaching it from the USB gadget device 172 * hierarchy. This is typically done when the function is unbound 173 * from a configuration but the instance is not yet freed. 174 */ 175 void gether_detach_gadget(struct net_device *net); 176 177 DEFINE_FREE(detach_gadget, struct net_device *, if (_T) gether_detach_gadget(_T)) 178 179 /** 180 * gether_set_dev_addr - initialize an ethernet-over-usb link with eth address 181 * @net: device representing this link 182 * @dev_addr: eth address of this device 183 * 184 * This sets the device-side Ethernet address of this ethernet-over-usb link 185 * if dev_addr is correct. 186 * Returns negative errno if the new address is incorrect. 187 */ 188 int gether_set_dev_addr(struct net_device *net, const char *dev_addr); 189 190 /** 191 * gether_get_dev_addr - get an ethernet-over-usb link eth address 192 * @net: device representing this link 193 * @dev_addr: place to store device's eth address 194 * @len: length of the @dev_addr buffer 195 * 196 * This gets the device-side Ethernet address of this ethernet-over-usb link. 197 * Returns zero on success, else negative errno. 198 */ 199 int gether_get_dev_addr(struct net_device *net, char *dev_addr, int len); 200 201 /** 202 * gether_set_host_addr - initialize an ethernet-over-usb link with host address 203 * @net: device representing this link 204 * @host_addr: eth address of the host 205 * 206 * This sets the host-side Ethernet address of this ethernet-over-usb link 207 * if host_addr is correct. 208 * Returns negative errno if the new address is incorrect. 209 */ 210 int gether_set_host_addr(struct net_device *net, const char *host_addr); 211 212 /** 213 * gether_get_host_addr - get an ethernet-over-usb link host address 214 * @net: device representing this link 215 * @host_addr: place to store eth address of the host 216 * @len: length of the @host_addr buffer 217 * 218 * This gets the host-side Ethernet address of this ethernet-over-usb link. 219 * Returns zero on success, else negative errno. 220 */ 221 int gether_get_host_addr(struct net_device *net, char *host_addr, int len); 222 223 /** 224 * gether_get_host_addr_cdc - get an ethernet-over-usb link host address 225 * @net: device representing this link 226 * @host_addr: place to store eth address of the host 227 * @len: length of the @host_addr buffer 228 * 229 * This gets the CDC formatted host-side Ethernet address of this 230 * ethernet-over-usb link. 231 * Returns zero on success, else negative errno. 232 */ 233 int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len); 234 235 /** 236 * gether_get_host_addr_u8 - get an ethernet-over-usb link host address 237 * @net: device representing this link 238 * @host_mac: place to store the eth address of the host 239 * 240 * This gets the binary formatted host-side Ethernet address of this 241 * ethernet-over-usb link. 242 */ 243 void gether_get_host_addr_u8(struct net_device *net, u8 host_mac[ETH_ALEN]); 244 245 /** 246 * gether_set_qmult - initialize an ethernet-over-usb link with a multiplier 247 * @net: device representing this link 248 * @qmult: queue multiplier 249 * 250 * This sets the queue length multiplier of this ethernet-over-usb link. 251 * For higher speeds use longer queues. 252 */ 253 void gether_set_qmult(struct net_device *net, unsigned qmult); 254 255 /** 256 * gether_get_qmult - get an ethernet-over-usb link multiplier 257 * @net: device representing this link 258 * 259 * This gets the queue length multiplier of this ethernet-over-usb link. 260 */ 261 unsigned gether_get_qmult(struct net_device *net); 262 263 /** 264 * gether_get_ifname - get an ethernet-over-usb link interface name 265 * @net: device representing this link 266 * @name: place to store the interface name 267 * @len: length of the @name buffer 268 * 269 * This gets the interface name of this ethernet-over-usb link. 270 * Returns zero on success, else negative errno. 271 */ 272 int gether_get_ifname(struct net_device *net, char *name, int len); 273 274 /** 275 * gether_set_ifname - set an ethernet-over-usb link interface name 276 * @net: device representing this link 277 * @name: new interface name 278 * @len: length of @name 279 * 280 * This sets the interface name of this ethernet-over-usb link. 281 * A single terminating newline, if any, is ignored. 282 * Returns zero on success, else negative errno. 283 */ 284 int gether_set_ifname(struct net_device *net, const char *name, int len); 285 286 void gether_cleanup(struct eth_dev *dev); 287 288 void gether_suspend(struct gether *link); 289 void gether_resume(struct gether *link); 290 291 /* connect/disconnect is handled by individual functions */ 292 struct net_device *gether_connect(struct gether *); 293 void gether_disconnect(struct gether *); 294 295 /* Some controllers can't support CDC Ethernet (ECM) ... */ 296 static inline bool can_support_ecm(struct usb_gadget *gadget) 297 { 298 if (!gadget_is_altset_supported(gadget)) 299 return false; 300 301 /* Everything else is *presumably* fine ... but this is a bit 302 * chancy, so be **CERTAIN** there are no hardware issues with 303 * your controller. Add it above if it can't handle CDC. 304 */ 305 return true; 306 } 307 308 /* peak (theoretical) bulk transfer rate in bits-per-second */ 309 static inline unsigned int gether_bitrate(struct usb_gadget *g) 310 { 311 if (g->speed >= USB_SPEED_SUPER_PLUS) 312 return 4250000000U; 313 if (g->speed == USB_SPEED_SUPER) 314 return 3750000000U; 315 else if (g->speed == USB_SPEED_HIGH) 316 return 13 * 512 * 8 * 1000 * 8; 317 else 318 return 19 * 64 * 1 * 1000 * 8; 319 } 320 321 #endif /* __U_ETHER_H */ 322