drivers/usb/net/cdc_subset.c

   1 /*
   2  * Simple "CDC Subset" USB Networking Links
   3  * Copyright (C) 2000-2005 by David Brownell
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/kmod.h>
  22 #include <linux/init.h>
  23 #include <linux/netdevice.h>
  24 #include <linux/etherdevice.h>
  25 #include <linux/ethtool.h>
  26 #include <linux/workqueue.h>
  27 #include <linux/mii.h>
  28 #include <linux/usb.h>
  29
  30 #include "usbnet.h"
  31
  32
  33 /*
  34  * This supports simple USB network links that don't require any special
  35  * framing or hardware control operations.  The protocol used here is a
  36  * strict subset of CDC Ethernet, with three basic differences reflecting
  37  * the goal that almost any hardware should run it:
  38  *
  39  *  - Minimal runtime control:  one interface, no altsettings, and
  40  *    no vendor or class specific control requests.  If a device is
  41  *    configured, it is allowed to exchange packets with the host.
  42  *    Fancier models would mean not working on some hardware.
  43  *
  44  *  - Minimal manufacturing control:  no IEEE "Organizationally
  45  *    Unique ID" required, or an EEPROMs to store one.  Each host uses
  46  *    one random "locally assigned" Ethernet address instead, which can
  47  *    of course be overridden using standard tools like "ifconfig".
  48  *    (With 2^46 such addresses, same-net collisions are quite rare.)
  49  *
  50  *  - There is no additional framing data for USB.  Packets are written
  51  *    exactly as in CDC Ethernet, starting with an Ethernet header and
  52  *    terminated by a short packet.  However, the host will never send a
  53  *    zero length packet; some systems can't handle those robustly.
  54  *
  55  * Anything that can transmit and receive USB bulk packets can implement
  56  * this protocol.  That includes both smart peripherals and quite a lot
  57  * of "host-to-host" USB cables (which embed two devices back-to-back).
  58  *
  59  * Note that although Linux may use many of those host-to-host links
  60  * with this "cdc_subset" framing, that doesn't mean there may not be a
  61  * better approach.  Handling the "other end unplugs/replugs" scenario
  62  * well tends to require chip-specific vendor requests.  Also, Windows
  63  * peers at the other end of host-to-host cables may expect their own
  64  * framing to be used rather than this "cdc_subset" model.
  65  */
  66
  67 #if defined(CONFIG_USB_EPSON2888) || defined(CONFIG_USB_ARMLINUX)
  68 /* PDA style devices are always connected if present */
  69 static int always_connected (struct usbnet *dev)
  70 {
  71         return 0;
  72 }
  73 #endif
  74
  75 #ifdef  CONFIG_USB_ALI_M5632
  76 #define HAVE_HARDWARE
  77
  78 /*-------------------------------------------------------------------------
  79  *
  80  * ALi M5632 driver ... does high speed
  81  *
  82  * NOTE that the MS-Windows drivers for this chip use some funky and
  83  * (naturally) undocumented 7-byte prefix to each packet, so this is a
  84  * case where we don't currently interoperate.  Also, once you unplug
  85  * one end of the cable, you need to replug the other end too ... since
  86  * chip docs are unavailable, there's no way to reset the relevant state
  87  * short of a power cycle.
  88  *
  89  *-------------------------------------------------------------------------*/
  90
  91 static const struct driver_info ali_m5632_info = {
  92         .description =  "ALi M5632",
  93 };
  94
  95 #endif
  96
  97 \f
  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         // no reset available!
 115         // no check_connect available!
 116
 117         .in = 2, .out = 2,              // direction distinguishes these
 118 };
 119
 120 #endif  /* CONFIG_USB_AN2720 */
 121
 122 \f
 123 #ifdef  CONFIG_USB_BELKIN
 124 #define HAVE_HARDWARE
 125
 126 /*-------------------------------------------------------------------------
 127  *
 128  * Belkin F5U104 ... two NetChip 2280 devices + Atmel AVR microcontroller
 129  *
 130  * ... also two eTEK designs, including one sold as "Advance USBNET"
 131  *
 132  *-------------------------------------------------------------------------*/
 133
 134 static const struct driver_info belkin_info = {
 135         .description =  "Belkin, eTEK, or compatible",
 136 };
 137
 138 #endif  /* CONFIG_USB_BELKIN */
 139
 140
 141 \f
 142 #ifdef  CONFIG_USB_EPSON2888
 143 #define HAVE_HARDWARE
 144
 145 /*-------------------------------------------------------------------------
 146  *
 147  * EPSON USB clients
 148  *
 149  * This is the same idea as Linux PDAs (below) except the firmware in the
 150  * device might not be Tux-powered.  Epson provides reference firmware that
 151  * implements this interface.  Product developers can reuse or modify that
 152  * code, such as by using their own product and vendor codes.
 153  *
 154  * Support was from Juro Bystricky <bystricky.juro@erd.epson.com>
 155  *
 156  *-------------------------------------------------------------------------*/
 157
 158 static const struct driver_info epson2888_info = {
 159         .description =  "Epson USB Device",
 160         .check_connect = always_connected,
 161
 162         .in = 4, .out = 3,
 163 };
 164
 165 #endif  /* CONFIG_USB_EPSON2888 */
 166
 167 \f
 168 /*-------------------------------------------------------------------------
 169  *
 170  * info from Jonathan McDowell <noodles@earth.li>
 171  *
 172  *-------------------------------------------------------------------------*/
 173 #ifdef CONFIG_USB_KC2190
 174 #define HAVE_HARDWARE
 175 static const struct driver_info kc2190_info = {
 176         .description =  "KC Technology KC-190",
 177 };
 178 #endif /* CONFIG_USB_KC2190 */
 179
 180 \f
 181 #ifdef  CONFIG_USB_ARMLINUX
 182 #define HAVE_HARDWARE
 183
 184 /*-------------------------------------------------------------------------
 185  *
 186  * Intel's SA-1100 chip integrates basic USB support, and is used
 187  * in PDAs like some iPaqs, the Yopy, some Zaurus models, and more.
 188  * When they run Linux, arch/arm/mach-sa1100/usb-eth.c may be used to
 189  * network using minimal USB framing data.
 190  *
 191  * This describes the driver currently in standard ARM Linux kernels.
 192  * The Zaurus uses a different driver (see later).
 193  *
 194  * PXA25x and PXA210 use XScale cores (ARM v5TE) with better USB support
 195  * and different USB endpoint numbering than the SA1100 devices.  The
 196  * mach-pxa/usb-eth.c driver re-uses the device ids from mach-sa1100
 197  * so we rely on the endpoint descriptors.
 198  *
 199  *-------------------------------------------------------------------------*/
 200
 201 static const struct driver_info linuxdev_info = {
 202         .description =  "Linux Device",
 203         .check_connect = always_connected,
 204 };
 205
 206 static const struct driver_info yopy_info = {
 207         .description =  "Yopy",
 208         .check_connect = always_connected,
 209 };
 210
 211 static const struct driver_info blob_info = {
 212         .description =  "Boot Loader OBject",
 213         .check_connect = always_connected,
 214 };
 215
 216 #endif  /* CONFIG_USB_ARMLINUX */
 217
 218 \f
 219 /*-------------------------------------------------------------------------*/
 220
 221 #ifndef HAVE_HARDWARE
 222 #error You need to configure some hardware for this driver
 223 #endif
 224
 225 /*
 226  * chip vendor names won't normally be on the cables, and
 227  * may not be on the device.
 228  */
 229
 230 static const struct usb_device_id       products [] = {
 231
 232 #ifdef  CONFIG_USB_ALI_M5632
 233 {
 234         USB_DEVICE (0x0402, 0x5632),    // ALi defaults
 235         .driver_info =  (unsigned long) &ali_m5632_info,
 236 },
 237 {
 238         USB_DEVICE (0x182d,0x207c),     // SiteCom CN-124
 239         .driver_info =  (unsigned long) &ali_m5632_info,
 240 },
 241 #endif
 242
 243 #ifdef  CONFIG_USB_AN2720
 244 {
 245         USB_DEVICE (0x0547, 0x2720),    // AnchorChips defaults
 246         .driver_info =  (unsigned long) &an2720_info,
 247 }, {
 248         USB_DEVICE (0x0547, 0x2727),    // Xircom PGUNET
 249         .driver_info =  (unsigned long) &an2720_info,
 250 },
 251 #endif
 252
 253 #ifdef  CONFIG_USB_BELKIN
 254 {
 255         USB_DEVICE (0x050d, 0x0004),    // Belkin
 256         .driver_info =  (unsigned long) &belkin_info,
 257 }, {
 258         USB_DEVICE (0x056c, 0x8100),    // eTEK
 259         .driver_info =  (unsigned long) &belkin_info,
 260 }, {
 261         USB_DEVICE (0x0525, 0x9901),    // Advance USBNET (eTEK)
 262         .driver_info =  (unsigned long) &belkin_info,
 263 },
 264 #endif
 265
 266 #ifdef  CONFIG_USB_EPSON2888
 267 {
 268         USB_DEVICE (0x0525, 0x2888),    // EPSON USB client
 269         .driver_info    = (unsigned long) &epson2888_info,
 270 },
 271 #endif
 272
 273 #ifdef CONFIG_USB_KC2190
 274 {
 275         USB_DEVICE (0x050f, 0x0190),    // KC-190
 276         .driver_info =  (unsigned long) &kc2190_info,
 277 },
 278 #endif
 279
 280 #ifdef  CONFIG_USB_ARMLINUX
 281 /*
 282  * SA-1100 using standard ARM Linux kernels, or compatible.
 283  * Often used when talking to Linux PDAs (iPaq, Yopy, etc).
 284  * The sa-1100 "usb-eth" driver handles the basic framing.
 285  *
 286  * PXA25x or PXA210 ...  these use a "usb-eth" driver much like
 287  * the sa1100 one, but hardware uses different endpoint numbers.
 288  *
 289  * Or the Linux "Ethernet" gadget on hardware that can't talk
 290  * CDC Ethernet (e.g., no altsettings), in either of two modes:
 291  *  - acting just like the old "usb-eth" firmware, though
 292  *    the implementation is different
 293  *  - supporting RNDIS as the first/default configuration for
 294  *    MS-Windows interop; Linux needs to use the other config
 295  */
 296 {
 297         // 1183 = 0x049F, both used as hex values?
 298         // Compaq "Itsy" vendor/product id
 299         USB_DEVICE (0x049F, 0x505A),    // usb-eth, or compatible
 300         .driver_info =  (unsigned long) &linuxdev_info,
 301 }, {
 302         USB_DEVICE (0x0E7E, 0x1001),    // G.Mate "Yopy"
 303         .driver_info =  (unsigned long) &yopy_info,
 304 }, {
 305         USB_DEVICE (0x8086, 0x07d3),    // "blob" bootloader
 306         .driver_info =  (unsigned long) &blob_info,
 307 }, {
 308         // Linux Ethernet/RNDIS gadget on pxa210/25x/26x, second config
 309         // e.g. Gumstix, current OpenZaurus, ...
 310         USB_DEVICE_VER (0x0525, 0xa4a2, 0x0203, 0x0203),
 311         .driver_info =  (unsigned long) &linuxdev_info,
 312 },
 313 #endif
 314
 315         { },            // END
 316 };
 317 MODULE_DEVICE_TABLE(usb, products);
 318
 319 /*-------------------------------------------------------------------------*/
 320
 321 static struct usb_driver cdc_subset_driver = {
 322         .name =         "cdc_subset",
 323         .probe =        usbnet_probe,
 324         .suspend =      usbnet_suspend,
 325         .resume =       usbnet_resume,
 326         .disconnect =   usbnet_disconnect,
 327         .id_table =     products,
 328 };
 329
 330 static int __init cdc_subset_init(void)
 331 {
 332         return usb_register(&cdc_subset_driver);
 333 }
 334 module_init(cdc_subset_init);
 335
 336 static void __exit cdc_subset_exit(void)
 337 {
 338         usb_deregister(&cdc_subset_driver);
 339 }
 340 module_exit(cdc_subset_exit);
 341
 342 MODULE_AUTHOR("David Brownell");
 343 MODULE_DESCRIPTION("Simple 'CDC Subset' USB networking links");
 344 MODULE_LICENSE("GPL");