1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Simple "CDC Subset" USB Networking Links
4 * Copyright (C) 2000-2005 by David Brownell
5 */
6
7 #include <linux/module.h>
8 #include <linux/kmod.h>
9 #include <linux/netdevice.h>
10 #include <linux/etherdevice.h>
11 #include <linux/ethtool.h>
12 #include <linux/workqueue.h>
13 #include <linux/mii.h>
14 #include <linux/usb.h>
15 #include <linux/usb/usbnet.h>
16
17
18 /*
19 * This supports simple USB network links that don't require any special
20 * framing or hardware control operations. The protocol used here is a
21 * strict subset of CDC Ethernet, with three basic differences reflecting
22 * the goal that almost any hardware should run it:
23 *
24 * - Minimal runtime control: one interface, no altsettings, and
25 * no vendor or class specific control requests. If a device is
26 * configured, it is allowed to exchange packets with the host.
27 * Fancier models would mean not working on some hardware.
28 *
29 * - Minimal manufacturing control: no IEEE "Organizationally
30 * Unique ID" required, or an EEPROMs to store one. Each host uses
31 * one random "locally assigned" Ethernet address instead, which can
32 * of course be overridden using standard tools like "ifconfig".
33 * (With 2^46 such addresses, same-net collisions are quite rare.)
34 *
35 * - There is no additional framing data for USB. Packets are written
36 * exactly as in CDC Ethernet, starting with an Ethernet header and
37 * terminated by a short packet. However, the host will never send a
38 * zero length packet; some systems can't handle those robustly.
39 *
40 * Anything that can transmit and receive USB bulk packets can implement
41 * this protocol. That includes both smart peripherals and quite a lot
42 * of "host-to-host" USB cables (which embed two devices back-to-back).
43 *
44 * Note that although Linux may use many of those host-to-host links
45 * with this "cdc_subset" framing, that doesn't mean there may not be a
46 * better approach. Handling the "other end unplugs/replugs" scenario
47 * well tends to require chip-specific vendor requests. Also, Windows
48 * peers at the other end of host-to-host cables may expect their own
49 * framing to be used rather than this "cdc_subset" model.
50 */
51
52 #if defined(CONFIG_USB_EPSON2888) || defined(CONFIG_USB_ARMLINUX)
53 /* PDA style devices are always connected if present */
54 static int always_connected (struct usbnet *dev)
55 {
56 return 0;
57 }
58 #endif
59
60 #ifdef CONFIG_USB_ALI_M5632
61 #define HAVE_HARDWARE
62
63 /*-------------------------------------------------------------------------
64 *
65 * ALi M5632 driver ... does high speed
66 *
67 * NOTE that the MS-Windows drivers for this chip use some funky and
68 * (naturally) undocumented 7-byte prefix to each packet, so this is a
69 * case where we don't currently interoperate. Also, once you unplug
70 * one end of the cable, you need to replug the other end too ... since
71 * chip docs are unavailable, there's no way to reset the relevant state
72 * short of a power cycle.
73 *
74 *-------------------------------------------------------------------------*/
75
76 static void m5632_recover(struct usbnet *dev)
77 {
78 struct usb_device *udev = dev->udev;
79 struct usb_interface *intf = dev->intf;
80 int r;
81
82 r = usb_lock_device_for_reset(udev, intf);
83 if (r < 0)
84 return;
85
86 usb_reset_device(udev);
87 usb_unlock_device(udev);
88 }
89
90 static const struct driver_info ali_m5632_info = {
91 .description = "ALi M5632",
92 .flags = FLAG_POINTTOPOINT,
93 .recover = m5632_recover,
94 };
95
96 #endif
97
98 #ifdef CONFIG_USB_AN2720
99 #define HAVE_HARDWARE
100
101 /*-------------------------------------------------------------------------
102 *
103 * AnchorChips 2720 driver ... http://www.cypress.com
104 *
105 * This doesn't seem to have a way to detect whether the peer is
106 * connected, or need any reset handshaking. It's got pretty big
107 * internal buffers (handles most of a frame's worth of data).
108 * Chip data sheets don't describe any vendor control messages.
109 *
110 *-------------------------------------------------------------------------*/
111
112 static const struct driver_info an2720_info = {
113 .description = "AnchorChips/Cypress 2720",
114 .flags = FLAG_POINTTOPOINT,
115 // no reset available!
116 // no check_connect available!
117
118 .in = 2, .out = 2, // direction distinguishes these
119 };
120
121 #endif /* CONFIG_USB_AN2720 */
122
123
124 #ifdef CONFIG_USB_BELKIN
125 #define HAVE_HARDWARE
126
127 /*-------------------------------------------------------------------------
128 *
129 * Belkin F5U104 ... two NetChip 2280 devices + Atmel AVR microcontroller
130 *
131 * ... also two eTEK designs, including one sold as "Advance USBNET"
132 *
133 *-------------------------------------------------------------------------*/
134
135 static const struct driver_info belkin_info = {
136 .description = "Belkin, eTEK, or compatible",
137 .flags = FLAG_POINTTOPOINT,
138 };
139
140 #endif /* CONFIG_USB_BELKIN */
141
142
143
144 #ifdef CONFIG_USB_EPSON2888
145 #define HAVE_HARDWARE
146
147 /*-------------------------------------------------------------------------
148 *
149 * EPSON USB clients
150 *
151 * This is the same idea as Linux PDAs (below) except the firmware in the
152 * device might not be Tux-powered. Epson provides reference firmware that
153 * implements this interface. Product developers can reuse or modify that
154 * code, such as by using their own product and vendor codes.
155 *
156 * Support was from Juro Bystricky <bystricky.juro@erd.epson.com>
157 *
158 *-------------------------------------------------------------------------*/
159
160 static const struct driver_info epson2888_info = {
161 .description = "Epson USB Device",
162 .check_connect = always_connected,
163 .flags = FLAG_POINTTOPOINT,
164
165 .in = 4, .out = 3,
166 };
167
168 #endif /* CONFIG_USB_EPSON2888 */
169
170
171 /*-------------------------------------------------------------------------
172 *
173 * info from Jonathan McDowell <noodles@earth.li>
174 *
175 *-------------------------------------------------------------------------*/
176 #ifdef CONFIG_USB_KC2190
177 #define HAVE_HARDWARE
178 static const struct driver_info kc2190_info = {
179 .description = "KC Technology KC-190",
180 .flags = FLAG_POINTTOPOINT,
181 };
182 #endif /* CONFIG_USB_KC2190 */
183
184
185 #ifdef CONFIG_USB_ARMLINUX
186 #define HAVE_HARDWARE
187
188 /*-------------------------------------------------------------------------
189 *
190 * Intel's SA-1100 chip integrates basic USB support, and is used
191 * in PDAs like some iPaqs, the Yopy, some Zaurus models, and more.
192 * When they run Linux, arch/arm/mach-sa1100/usb-eth.c may be used to
193 * network using minimal USB framing data.
194 *
195 * This describes the driver currently in standard ARM Linux kernels.
196 * The Zaurus uses a different driver (see later).
197 *
198 * PXA25x and PXA210 use XScale cores (ARM v5TE) with better USB support
199 * and different USB endpoint numbering than the SA1100 devices. The
200 * mach-pxa/usb-eth.c driver re-uses the device ids from mach-sa1100
201 * so we rely on the endpoint descriptors.
202 *
203 *-------------------------------------------------------------------------*/
204
205 static const struct driver_info linuxdev_info = {
206 .description = "Linux Device",
207 .check_connect = always_connected,
208 .flags = FLAG_POINTTOPOINT,
209 };
210
211 static const struct driver_info yopy_info = {
212 .description = "Yopy",
213 .check_connect = always_connected,
214 .flags = FLAG_POINTTOPOINT,
215 };
216
217 static const struct driver_info blob_info = {
218 .description = "Boot Loader OBject",
219 .check_connect = always_connected,
220 .flags = FLAG_POINTTOPOINT,
221 };
222
223 #endif /* CONFIG_USB_ARMLINUX */
224
225
226 /*-------------------------------------------------------------------------*/
227
228 #ifndef HAVE_HARDWARE
229 #warning You need to configure some hardware for this driver
230 #endif
231
232 /*
233 * chip vendor names won't normally be on the cables, and
234 * may not be on the device.
235 */
236
237 static const struct usb_device_id products [] = {
238
239 #ifdef CONFIG_USB_ALI_M5632
240 {
241 USB_DEVICE (0x0402, 0x5632), // ALi defaults
242 .driver_info = (unsigned long) &ali_m5632_info,
243 },
244 {
245 USB_DEVICE (0x182d,0x207c), // SiteCom CN-124
246 .driver_info = (unsigned long) &ali_m5632_info,
247 },
248 #endif
249
250 #ifdef CONFIG_USB_AN2720
251 {
252 USB_DEVICE (0x0547, 0x2720), // AnchorChips defaults
253 .driver_info = (unsigned long) &an2720_info,
254 }, {
255 USB_DEVICE (0x0547, 0x2727), // Xircom PGUNET
256 .driver_info = (unsigned long) &an2720_info,
257 },
258 #endif
259
260 #ifdef CONFIG_USB_BELKIN
261 {
262 USB_DEVICE (0x050d, 0x0004), // Belkin
263 .driver_info = (unsigned long) &belkin_info,
264 }, {
265 USB_DEVICE (0x056c, 0x8100), // eTEK
266 .driver_info = (unsigned long) &belkin_info,
267 }, {
268 USB_DEVICE (0x0525, 0x9901), // Advance USBNET (eTEK)
269 .driver_info = (unsigned long) &belkin_info,
270 },
271 #endif
272
273 #ifdef CONFIG_USB_EPSON2888
274 {
275 USB_DEVICE (0x0525, 0x2888), // EPSON USB client
276 .driver_info = (unsigned long) &epson2888_info,
277 },
278 #endif
279
280 #ifdef CONFIG_USB_KC2190
281 {
282 USB_DEVICE (0x050f, 0x0190), // KC-190
283 .driver_info = (unsigned long) &kc2190_info,
284 },
285 #endif
286
287 #ifdef CONFIG_USB_ARMLINUX
288 /*
289 * SA-1100 using standard ARM Linux kernels, or compatible.
290 * Often used when talking to Linux PDAs (iPaq, Yopy, etc).
291 * The sa-1100 "usb-eth" driver handles the basic framing.
292 *
293 * PXA25x or PXA210 ... these use a "usb-eth" driver much like
294 * the sa1100 one, but hardware uses different endpoint numbers.
295 *
296 * Or the Linux "Ethernet" gadget on hardware that can't talk
297 * CDC Ethernet (e.g., no altsettings), in either of two modes:
298 * - acting just like the old "usb-eth" firmware, though
299 * the implementation is different
300 * - supporting RNDIS as the first/default configuration for
301 * MS-Windows interop; Linux needs to use the other config
302 */
303 {
304 // 1183 = 0x049F, both used as hex values?
305 // Compaq "Itsy" vendor/product id
306 USB_DEVICE (0x049F, 0x505A), // usb-eth, or compatible
307 .driver_info = (unsigned long) &linuxdev_info,
308 }, {
309 USB_DEVICE (0x0E7E, 0x1001), // G.Mate "Yopy"
310 .driver_info = (unsigned long) &yopy_info,
311 }, {
312 USB_DEVICE (0x8086, 0x07d3), // "blob" bootloader
313 .driver_info = (unsigned long) &blob_info,
314 }, {
315 USB_DEVICE (0x1286, 0x8001), // "blob" bootloader
316 .driver_info = (unsigned long) &blob_info,
317 }, {
318 // Linux Ethernet/RNDIS gadget, mostly on PXA, second config
319 // e.g. Gumstix, current OpenZaurus, ... or anything else
320 // that just enables this gadget option.
321 USB_DEVICE (0x0525, 0xa4a2),
322 .driver_info = (unsigned long) &linuxdev_info,
323 },
324 #endif
325
326 { }, // END
327 };
328 MODULE_DEVICE_TABLE(usb, products);
329
330 /*-------------------------------------------------------------------------*/
331 static int dummy_prereset(struct usb_interface *intf)
332 {
333 return 0;
334 }
335
336 static int dummy_postreset(struct usb_interface *intf)
337 {
338 return 0;
339 }
340
341 static struct usb_driver cdc_subset_driver = {
342 .name = "cdc_subset",
343 .probe = usbnet_probe,
344 .suspend = usbnet_suspend,
345 .resume = usbnet_resume,
346 .pre_reset = dummy_prereset,
347 .post_reset = dummy_postreset,
348 .disconnect = usbnet_disconnect,
349 .id_table = products,
350 .disable_hub_initiated_lpm = 1,
351 };
352
353 module_usb_driver(cdc_subset_driver);
354
355 MODULE_AUTHOR("David Brownell");
356 MODULE_DESCRIPTION("Simple 'CDC Subset' USB networking links");
357 MODULE_LICENSE("GPL");