2 * ether.c -- Ethernet gadget driver, with CDC and non-CDC options
4 * Copyright (C) 2003-2005,2008 David Brownell
5 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
6 * Copyright (C) 2008 Nokia Corporation
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.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 /* #define VERBOSE_DEBUG */
25 #include <linux/kernel.h>
26 #include <linux/utsname.h>
29 #if defined USB_ETH_RNDIS
32 #ifdef CONFIG_USB_ETH_RNDIS
33 # define USB_ETH_RNDIS y
40 * Ethernet gadget driver -- with CDC and non-CDC options
41 * Builds on hardware support for a full duplex link.
43 * CDC Ethernet is the standard USB solution for sending Ethernet frames
44 * using USB. Real hardware tends to use the same framing protocol but look
45 * different for control features. This driver strongly prefers to use
46 * this USB-IF standard as its open-systems interoperability solution;
47 * most host side USB stacks (except from Microsoft) support it.
49 * This is sometimes called "CDC ECM" (Ethernet Control Model) to support
50 * TLA-soup. "CDC ACM" (Abstract Control Model) is for modems, and a new
51 * "CDC EEM" (Ethernet Emulation Model) is starting to spread.
53 * There's some hardware that can't talk CDC ECM. We make that hardware
54 * implement a "minimalist" vendor-agnostic CDC core: same framing, but
55 * link-level setup only requires activating the configuration. Only the
56 * endpoint descriptors, and product/vendor IDs, are relevant; no control
57 * operations are available. Linux supports it, but other host operating
58 * systems may not. (This is a subset of CDC Ethernet.)
60 * It turns out that if you add a few descriptors to that "CDC Subset",
61 * (Windows) host side drivers from MCCI can treat it as one submode of
62 * a proprietary scheme called "SAFE" ... without needing to know about
63 * specific product/vendor IDs. So we do that, making it easier to use
64 * those MS-Windows drivers. Those added descriptors make it resemble a
65 * CDC MDLM device, but they don't change device behavior at all. (See
66 * MCCI Engineering report 950198 "SAFE Networking Functions".)
68 * A third option is also in use. Rather than CDC Ethernet, or something
69 * simpler, Microsoft pushes their own approach: RNDIS. The published
70 * RNDIS specs are ambiguous and appear to be incomplete, and are also
71 * needlessly complex. They borrow more from CDC ACM than CDC ECM.
74 #define DRIVER_DESC "Ethernet Gadget"
75 #define DRIVER_VERSION "Memorial Day 2008"
78 #define PREFIX "RNDIS/"
84 * This driver aims for interoperability by using CDC ECM unless
88 * returns false, in which case it supports the CDC Subset. By default,
89 * that returns true; most hardware has no problems with CDC ECM, that's
90 * a good default. Previous versions of this driver had no default; this
91 * version changes that, removing overhead for new controller support.
93 * IF YOUR HARDWARE CAN'T SUPPORT CDC ECM, UPDATE THAT ROUTINE!
96 static inline bool has_rndis(void)
105 /*-------------------------------------------------------------------------*/
108 * Kbuild is not very cooperative with respect to linking separately
109 * compiled library objects into one module. So for now we won't use
110 * separate compilation ... ensuring init/exit sections work to shrink
111 * the runtime footprint, and giving us at least some parts of what
112 * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
114 #include "composite.c"
115 #include "usbstring.c"
117 #include "epautoconf.c"
120 #include "f_subset.c"
128 /*-------------------------------------------------------------------------*/
130 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!!
131 * Instead: allocate your own, using normal USB-IF procedures.
134 /* Thanks to NetChip Technologies for donating this product ID.
135 * It's for devices with only CDC Ethernet configurations.
137 #define CDC_VENDOR_NUM 0x0525 /* NetChip */
138 #define CDC_PRODUCT_NUM 0xa4a1 /* Linux-USB Ethernet Gadget */
140 /* For hardware that can't talk CDC, we use the same vendor ID that
141 * ARM Linux has used for ethernet-over-usb, both with sa1100 and
142 * with pxa250. We're protocol-compatible, if the host-side drivers
143 * use the endpoint descriptors. bcdDevice (version) is nonzero, so
144 * drivers that need to hard-wire endpoint numbers have a hook.
146 * The protocol is a minimal subset of CDC Ether, which works on any bulk
147 * hardware that's not deeply broken ... even on hardware that can't talk
148 * RNDIS (like SA-1100, with no interrupt endpoint, or anything that
149 * doesn't handle control-OUT).
151 #define SIMPLE_VENDOR_NUM 0x049f
152 #define SIMPLE_PRODUCT_NUM 0x505a
154 /* For hardware that can talk RNDIS and either of the above protocols,
155 * use this ID ... the windows INF files will know it. Unless it's
156 * used with CDC Ethernet, Linux 2.4 hosts will need updates to choose
157 * the non-RNDIS configuration.
159 #define RNDIS_VENDOR_NUM 0x0525 /* NetChip */
160 #define RNDIS_PRODUCT_NUM 0xa4a2 /* Ethernet/RNDIS Gadget */
162 /* For EEM gadgets */
163 #define EEM_VENDOR_NUM 0x1d6b /* Linux Foundation */
164 #define EEM_PRODUCT_NUM 0x0102 /* EEM Gadget */
166 /*-------------------------------------------------------------------------*/
168 static struct usb_device_descriptor device_desc
= {
169 .bLength
= sizeof device_desc
,
170 .bDescriptorType
= USB_DT_DEVICE
,
172 .bcdUSB
= cpu_to_le16 (0x0200),
174 .bDeviceClass
= USB_CLASS_COMM
,
175 .bDeviceSubClass
= 0,
176 .bDeviceProtocol
= 0,
177 /* .bMaxPacketSize0 = f(hardware) */
179 /* Vendor and product id defaults change according to what configs
180 * we support. (As does bNumConfigurations.) These values can
181 * also be overridden by module parameters.
183 .idVendor
= cpu_to_le16 (CDC_VENDOR_NUM
),
184 .idProduct
= cpu_to_le16 (CDC_PRODUCT_NUM
),
185 /* .bcdDevice = f(hardware) */
186 /* .iManufacturer = DYNAMIC */
187 /* .iProduct = DYNAMIC */
188 /* NO SERIAL NUMBER */
189 .bNumConfigurations
= 1,
192 static struct usb_otg_descriptor otg_descriptor
= {
193 .bLength
= sizeof otg_descriptor
,
194 .bDescriptorType
= USB_DT_OTG
,
196 /* REVISIT SRP-only hardware is possible, although
197 * it would not be called "OTG" ...
199 .bmAttributes
= USB_OTG_SRP
| USB_OTG_HNP
,
202 static const struct usb_descriptor_header
*otg_desc
[] = {
203 (struct usb_descriptor_header
*) &otg_descriptor
,
208 /* string IDs are assigned dynamically */
210 #define STRING_MANUFACTURER_IDX 0
211 #define STRING_PRODUCT_IDX 1
213 static char manufacturer
[50];
215 static struct usb_string strings_dev
[] = {
216 [STRING_MANUFACTURER_IDX
].s
= manufacturer
,
217 [STRING_PRODUCT_IDX
].s
= PREFIX DRIVER_DESC
,
218 { } /* end of list */
221 static struct usb_gadget_strings stringtab_dev
= {
222 .language
= 0x0409, /* en-us */
223 .strings
= strings_dev
,
226 static struct usb_gadget_strings
*dev_strings
[] = {
231 static u8 hostaddr
[ETH_ALEN
];
233 /*-------------------------------------------------------------------------*/
236 * We may not have an RNDIS configuration, but if we do it needs to be
237 * the first one present. That's to make Microsoft's drivers happy,
238 * and to follow DOCSIS 1.0 (cable modem standard).
240 static int __init
rndis_do_config(struct usb_configuration
*c
)
242 /* FIXME alloc iConfiguration string, set it in c->strings */
244 if (gadget_is_otg(c
->cdev
->gadget
)) {
245 c
->descriptors
= otg_desc
;
246 c
->bmAttributes
|= USB_CONFIG_ATT_WAKEUP
;
249 return rndis_bind_config(c
, hostaddr
);
252 static struct usb_configuration rndis_config_driver
= {
254 .bConfigurationValue
= 2,
255 /* .iConfiguration = DYNAMIC */
256 .bmAttributes
= USB_CONFIG_ATT_SELFPOWER
,
259 /*-------------------------------------------------------------------------*/
261 #ifdef CONFIG_USB_ETH_EEM
262 static int use_eem
= 1;
266 module_param(use_eem
, bool, 0);
267 MODULE_PARM_DESC(use_eem
, "use CDC EEM mode");
270 * We _always_ have an ECM, CDC Subset, or EEM configuration.
272 static int __init
eth_do_config(struct usb_configuration
*c
)
274 /* FIXME alloc iConfiguration string, set it in c->strings */
276 if (gadget_is_otg(c
->cdev
->gadget
)) {
277 c
->descriptors
= otg_desc
;
278 c
->bmAttributes
|= USB_CONFIG_ATT_WAKEUP
;
282 return eem_bind_config(c
);
283 else if (can_support_ecm(c
->cdev
->gadget
))
284 return ecm_bind_config(c
, hostaddr
);
286 return geth_bind_config(c
, hostaddr
);
289 static struct usb_configuration eth_config_driver
= {
290 /* .label = f(hardware) */
291 .bConfigurationValue
= 1,
292 /* .iConfiguration = DYNAMIC */
293 .bmAttributes
= USB_CONFIG_ATT_SELFPOWER
,
296 /*-------------------------------------------------------------------------*/
298 static int __init
eth_bind(struct usb_composite_dev
*cdev
)
301 struct usb_gadget
*gadget
= cdev
->gadget
;
304 /* set up network link layer */
305 status
= gether_setup(cdev
->gadget
, hostaddr
);
309 /* set up main config label and device descriptor */
312 eth_config_driver
.label
= "CDC Ethernet (EEM)";
313 device_desc
.idVendor
= cpu_to_le16(EEM_VENDOR_NUM
);
314 device_desc
.idProduct
= cpu_to_le16(EEM_PRODUCT_NUM
);
315 } else if (can_support_ecm(cdev
->gadget
)) {
317 eth_config_driver
.label
= "CDC Ethernet (ECM)";
320 eth_config_driver
.label
= "CDC Subset/SAFE";
322 device_desc
.idVendor
= cpu_to_le16(SIMPLE_VENDOR_NUM
);
323 device_desc
.idProduct
= cpu_to_le16(SIMPLE_PRODUCT_NUM
);
325 device_desc
.bDeviceClass
= USB_CLASS_VENDOR_SPEC
;
329 /* RNDIS plus ECM-or-Subset */
330 device_desc
.idVendor
= cpu_to_le16(RNDIS_VENDOR_NUM
);
331 device_desc
.idProduct
= cpu_to_le16(RNDIS_PRODUCT_NUM
);
332 device_desc
.bNumConfigurations
= 2;
335 gcnum
= usb_gadget_controller_number(gadget
);
337 device_desc
.bcdDevice
= cpu_to_le16(0x0300 | gcnum
);
339 /* We assume that can_support_ecm() tells the truth;
340 * but if the controller isn't recognized at all then
341 * that assumption is a bit more likely to be wrong.
343 dev_warn(&gadget
->dev
,
344 "controller '%s' not recognized; trying %s\n",
346 eth_config_driver
.label
);
347 device_desc
.bcdDevice
=
348 cpu_to_le16(0x0300 | 0x0099);
352 /* Allocate string descriptor numbers ... note that string
353 * contents can be overridden by the composite_dev glue.
356 /* device descriptor strings: manufacturer, product */
357 snprintf(manufacturer
, sizeof manufacturer
, "%s %s with %s",
358 init_utsname()->sysname
, init_utsname()->release
,
360 status
= usb_string_id(cdev
);
363 strings_dev
[STRING_MANUFACTURER_IDX
].id
= status
;
364 device_desc
.iManufacturer
= status
;
366 status
= usb_string_id(cdev
);
369 strings_dev
[STRING_PRODUCT_IDX
].id
= status
;
370 device_desc
.iProduct
= status
;
372 /* register our configuration(s); RNDIS first, if it's used */
374 status
= usb_add_config(cdev
, &rndis_config_driver
,
380 status
= usb_add_config(cdev
, ð_config_driver
, eth_do_config
);
384 dev_info(&gadget
->dev
, "%s, version: " DRIVER_VERSION
"\n",
394 static int __exit
eth_unbind(struct usb_composite_dev
*cdev
)
400 static struct usb_composite_driver eth_driver
= {
403 .strings
= dev_strings
,
404 .max_speed
= USB_SPEED_HIGH
,
405 .unbind
= __exit_p(eth_unbind
),
408 MODULE_DESCRIPTION(PREFIX DRIVER_DESC
);
409 MODULE_AUTHOR("David Brownell, Benedikt Spanger");
410 MODULE_LICENSE("GPL");
412 static int __init
init(void)
414 return usb_composite_probe(ð_driver
, eth_bind
);
418 static void __exit
cleanup(void)
420 usb_composite_unregister(ð_driver
);
422 module_exit(cleanup
);