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 */
gether_setup(struct usb_gadget * g,const char * dev_addr,const char * host_addr,u8 ethaddr[ETH_ALEN],unsigned qmult)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 */
gether_setup_default(void)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) ... */
can_support_ecm(struct usb_gadget * gadget)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 */
gether_bitrate(struct usb_gadget * g)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