drivers/net/usb/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, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/kmod.h>
  21 #include <linux/netdevice.h>
  22 #include <linux/etherdevice.h>
  23 #include <linux/ethtool.h>
  24 #include <linux/workqueue.h>
  25 #include <linux/mii.h>
  26 #include <linux/usb.h>
  27 #include <linux/usb/usbnet.h>
  28
  29
  30 /*
  31  * This supports simple USB network links that don't require any special
  32  * framing or hardware control operations.  The protocol used here is a
  33  * strict subset of CDC Ethernet, with three basic differences reflecting
  34  * the goal that almost any hardware should run it:
  35  *
  36  *  - Minimal runtime control:  one interface, no altsettings, and
  37  *    no vendor or class specific control requests.  If a device is
  38  *    configured, it is allowed to exchange packets with the host.
  39  *    Fancier models would mean not working on some hardware.
  40  *
  41  *  - Minimal manufacturing control:  no IEEE "Organizationally
  42  *    Unique ID" required, or an EEPROMs to store one.  Each host uses
  43  *    one random "locally assigned" Ethernet address instead, which can
  44  *    of course be overridden using standard tools like "ifconfig".
  45  *    (With 2^46 such addresses, same-net collisions are quite rare.)
  46  *
  47  *  - There is no additional framing data for USB.  Packets are written
  48  *    exactly as in CDC Ethernet, starting with an Ethernet header and
  49  *    terminated by a short packet.  However, the host will never send a
  50  *    zero length packet; some systems can't handle those robustly.
  51  *
  52  * Anything that can transmit and receive USB bulk packets can implement
  53  * this protocol.  That includes both smart peripherals and quite a lot
  54  * of "host-to-host" USB cables (which embed two devices back-to-back).
  55  *
  56  * Note that although Linux may use many of those host-to-host links
  57  * with this "cdc_subset" framing, that doesn't mean there may not be a
  58  * better approach.  Handling the "other end unplugs/replugs" scenario
  59  * well tends to require chip-specific vendor requests.  Also, Windows
  60  * peers at the other end of host-to-host cables may expect their own
  61  * framing to be used rather than this "cdc_subset" model.
  62  */
  63
  64 #if defined(CONFIG_USB_EPSON2888) || defined(CONFIG_USB_ARMLINUX)
  65 /* PDA style devices are always connected if present */
  66 static int always_connected (struct usbnet *dev)
  67 {
  68         return 0;
  69 }
  70 #endif
  71
  72 #ifdef  CONFIG_USB_ALI_M5632
  73 #define HAVE_HARDWARE
  74
  75 /*-------------------------------------------------------------------------
  76  *
  77  * ALi M5632 driver ... does high speed
  78  *
  79  * NOTE that the MS-Windows drivers for this chip use some funky and
  80  * (naturally) undocumented 7-byte prefix to each packet, so this is a
  81  * case where we don't currently interoperate.  Also, once you unplug
  82  * one end of the cable, you need to replug the other end too ... since
  83  * chip docs are unavailable, there's no way to reset the relevant state
  84  * short of a power cycle.
  85  *
  86  *-------------------------------------------------------------------------*/
  87
  88 static void m5632_recover(struct usbnet *dev)
  89 {
  90         struct usb_device       *udev = dev->udev;
  91         struct usb_interface    *intf = dev->intf;
  92         int r;
  93
  94         r = usb_lock_device_for_reset(udev, intf);
  95         if (r < 0)
  96                 return;
  97
  98         usb_reset_device(udev);
  99         usb_unlock_device(udev);
 100 }
 101
 102 static const struct driver_info ali_m5632_info = {
 103         .description =  "ALi M5632",
 104         .flags       = FLAG_POINTTOPOINT,
 105         .recover     = m5632_recover,
 106 };
 107
 108 #endif
 109
 110 #ifdef  CONFIG_USB_AN2720
 111 #define HAVE_HARDWARE
 112
 113 /*-------------------------------------------------------------------------
 114  *
 115  * AnchorChips 2720 driver ... http://www.cypress.com
 116  *
 117  * This doesn't seem to have a way to detect whether the peer is
 118  * connected, or need any reset handshaking.  It's got pretty big
 119  * internal buffers (handles most of a frame's worth of data).
 120  * Chip data sheets don't describe any vendor control messages.
 121  *
 122  *-------------------------------------------------------------------------*/
 123
 124 static const struct driver_info an2720_info = {
 125         .description =  "AnchorChips/Cypress 2720",
 126         .flags       = FLAG_POINTTOPOINT,
 127         // no reset available!
 128         // no check_connect available!
 129
 130         .in = 2, .out = 2,              // direction distinguishes these
 131 };
 132
 133 #endif  /* CONFIG_USB_AN2720 */
 134
 135 \f
 136 #ifdef  CONFIG_USB_BELKIN
 137 #define HAVE_HARDWARE
 138
 139 /*-------------------------------------------------------------------------
 140  *
 141  * Belkin F5U104 ... two NetChip 2280 devices + Atmel AVR microcontroller
 142  *
 143  * ... also two eTEK designs, including one sold as "Advance USBNET"
 144  *
 145  *-------------------------------------------------------------------------*/
 146
 147 static const struct driver_info belkin_info = {
 148         .description =  "Belkin, eTEK, or compatible",
 149         .flags       = FLAG_POINTTOPOINT,
 150 };
 151
 152 #endif  /* CONFIG_USB_BELKIN */
 153
 154
 155 \f
 156 #ifdef  CONFIG_USB_EPSON2888
 157 #define HAVE_HARDWARE
 158
 159 /*-------------------------------------------------------------------------
 160  *
 161  * EPSON USB clients
 162  *
 163  * This is the same idea as Linux PDAs (below) except the firmware in the
 164  * device might not be Tux-powered.  Epson provides reference firmware that
 165  * implements this interface.  Product developers can reuse or modify that
 166  * code, such as by using their own product and vendor codes.
 167  *
 168  * Support was from Juro Bystricky <bystricky.juro@erd.epson.com>
 169  *
 170  *-------------------------------------------------------------------------*/
 171
 172 static const struct driver_info epson2888_info = {
 173         .description =  "Epson USB Device",
 174         .check_connect = always_connected,
 175         .flags = FLAG_POINTTOPOINT,
 176
 177         .in = 4, .out = 3,
 178 };
 179
 180 #endif  /* CONFIG_USB_EPSON2888 */
 181
 182 \f
 183 /*-------------------------------------------------------------------------
 184  *
 185  * info from Jonathan McDowell <noodles@earth.li>
 186  *
 187  *-------------------------------------------------------------------------*/
 188 #ifdef CONFIG_USB_KC2190
 189 #define HAVE_HARDWARE
 190 static const struct driver_info kc2190_info = {
 191         .description =  "KC Technology KC-190",
 192         .flags = FLAG_POINTTOPOINT,
 193 };
 194 #endif /* CONFIG_USB_KC2190 */
 195
 196 \f
 197 #ifdef  CONFIG_USB_ARMLINUX
 198 #define HAVE_HARDWARE
 199
 200 /*-------------------------------------------------------------------------
 201  *
 202  * Intel's SA-1100 chip integrates basic USB support, and is used
 203  * in PDAs like some iPaqs, the Yopy, some Zaurus models, and more.
 204  * When they run Linux, arch/arm/mach-sa1100/usb-eth.c may be used to
 205  * network using minimal USB framing data.
 206  *
 207  * This describes the driver currently in standard ARM Linux kernels.
 208  * The Zaurus uses a different driver (see later).
 209  *
 210  * PXA25x and PXA210 use XScale cores (ARM v5TE) with better USB support
 211  * and different USB endpoint numbering than the SA1100 devices.  The
 212  * mach-pxa/usb-eth.c driver re-uses the device ids from mach-sa1100
 213  * so we rely on the endpoint descriptors.
 214  *
 215  *-------------------------------------------------------------------------*/
 216
 217 static const struct driver_info linuxdev_info = {
 218         .description =  "Linux Device",
 219         .check_connect = always_connected,
 220         .flags = FLAG_POINTTOPOINT,
 221 };
 222
 223 static const struct driver_info yopy_info = {
 224         .description =  "Yopy",
 225         .check_connect = always_connected,
 226         .flags = FLAG_POINTTOPOINT,
 227 };
 228
 229 static const struct driver_info blob_info = {
 230         .description =  "Boot Loader OBject",
 231         .check_connect = always_connected,
 232         .flags = FLAG_POINTTOPOINT,
 233 };
 234
 235 #endif  /* CONFIG_USB_ARMLINUX */
 236
 237 \f
 238 /*-------------------------------------------------------------------------*/
 239
 240 #ifndef HAVE_HARDWARE
 241 #warning You need to configure some hardware for this driver
 242 #endif
 243
 244 /*
 245  * chip vendor names won't normally be on the cables, and
 246  * may not be on the device.
 247  */
 248
 249 static const struct usb_device_id       products [] = {
 250
 251 #ifdef  CONFIG_USB_ALI_M5632
 252 {
 253         USB_DEVICE (0x0402, 0x5632),    // ALi defaults
 254         .driver_info =  (unsigned long) &ali_m5632_info,
 255 },
 256 {
 257         USB_DEVICE (0x182d,0x207c),     // SiteCom CN-124
 258         .driver_info =  (unsigned long) &ali_m5632_info,
 259 },
 260 #endif
 261
 262 #ifdef  CONFIG_USB_AN2720
 263 {
 264         USB_DEVICE (0x0547, 0x2720),    // AnchorChips defaults
 265         .driver_info =  (unsigned long) &an2720_info,
 266 }, {
 267         USB_DEVICE (0x0547, 0x2727),    // Xircom PGUNET
 268         .driver_info =  (unsigned long) &an2720_info,
 269 },
 270 #endif
 271
 272 #ifdef  CONFIG_USB_BELKIN
 273 {
 274         USB_DEVICE (0x050d, 0x0004),    // Belkin
 275         .driver_info =  (unsigned long) &belkin_info,
 276 }, {
 277         USB_DEVICE (0x056c, 0x8100),    // eTEK
 278         .driver_info =  (unsigned long) &belkin_info,
 279 }, {
 280         USB_DEVICE (0x0525, 0x9901),    // Advance USBNET (eTEK)
 281         .driver_info =  (unsigned long) &belkin_info,
 282 },
 283 #endif
 284
 285 #ifdef  CONFIG_USB_EPSON2888
 286 {
 287         USB_DEVICE (0x0525, 0x2888),    // EPSON USB client
 288         .driver_info    = (unsigned long) &epson2888_info,
 289 },
 290 #endif
 291
 292 #ifdef CONFIG_USB_KC2190
 293 {
 294         USB_DEVICE (0x050f, 0x0190),    // KC-190
 295         .driver_info =  (unsigned long) &kc2190_info,
 296 },
 297 #endif
 298
 299 #ifdef  CONFIG_USB_ARMLINUX
 300 /*
 301  * SA-1100 using standard ARM Linux kernels, or compatible.
 302  * Often used when talking to Linux PDAs (iPaq, Yopy, etc).
 303  * The sa-1100 "usb-eth" driver handles the basic framing.
 304  *
 305  * PXA25x or PXA210 ...  these use a "usb-eth" driver much like
 306  * the sa1100 one, but hardware uses different endpoint numbers.
 307  *
 308  * Or the Linux "Ethernet" gadget on hardware that can't talk
 309  * CDC Ethernet (e.g., no altsettings), in either of two modes:
 310  *  - acting just like the old "usb-eth" firmware, though
 311  *    the implementation is different
 312  *  - supporting RNDIS as the first/default configuration for
 313  *    MS-Windows interop; Linux needs to use the other config
 314  */
 315 {
 316         // 1183 = 0x049F, both used as hex values?
 317         // Compaq "Itsy" vendor/product id
 318         USB_DEVICE (0x049F, 0x505A),    // usb-eth, or compatible
 319         .driver_info =  (unsigned long) &linuxdev_info,
 320 }, {
 321         USB_DEVICE (0x0E7E, 0x1001),    // G.Mate "Yopy"
 322         .driver_info =  (unsigned long) &yopy_info,
 323 }, {
 324         USB_DEVICE (0x8086, 0x07d3),    // "blob" bootloader
 325         .driver_info =  (unsigned long) &blob_info,
 326 }, {
 327         USB_DEVICE (0x1286, 0x8001),    // "blob" bootloader
 328         .driver_info =  (unsigned long) &blob_info,
 329 }, {
 330         // Linux Ethernet/RNDIS gadget, mostly on PXA, second config
 331         // e.g. Gumstix, current OpenZaurus, ... or anything else
 332         // that just enables this gadget option.
 333         USB_DEVICE (0x0525, 0xa4a2),
 334         .driver_info =  (unsigned long) &linuxdev_info,
 335 },
 336 #endif
 337
 338         { },            // END
 339 };
 340 MODULE_DEVICE_TABLE(usb, products);
 341
 342 /*-------------------------------------------------------------------------*/
 343 static int dummy_prereset(struct usb_interface *intf)
 344 {
 345         return 0;
 346 }
 347
 348 static int dummy_postreset(struct usb_interface *intf)
 349 {
 350         return 0;
 351 }
 352
 353 static struct usb_driver cdc_subset_driver = {
 354         .name =         "cdc_subset",
 355         .probe =        usbnet_probe,
 356         .suspend =      usbnet_suspend,
 357         .resume =       usbnet_resume,
 358         .pre_reset =    dummy_prereset,
 359         .post_reset =   dummy_postreset,
 360         .disconnect =   usbnet_disconnect,
 361         .id_table =     products,
 362         .disable_hub_initiated_lpm = 1,
 363 };
 364
 365 module_usb_driver(cdc_subset_driver);
 366
 367 MODULE_AUTHOR("David Brownell");
 368 MODULE_DESCRIPTION("Simple 'CDC Subset' USB networking links");
 369 MODULE_LICENSE("GPL");