[PATCH] USB: usbnet (2/9) module for simple network links

This patch creates the first of several separate "minidriver" modules
for "usbnet".  This one handles only the very simplest hardware, which
can be handled almost entirely by the "usbnet" core.

    - Move device-specific bits into new "cdc_subset.c" driver,
      shrinking "usbnet" by a bunch;

    - Export the functions needed to support this minidriver
      (with EXPORT_SYMBOL_GPL);

    - Update Kconfig and kbuild accordingly.

This one handles about a dozen different device types, with the most
notable ones being Gumstix and most Linux-based PDAs (except Zaurus
running that ancient code from Sharp).

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 335 insertions, 0 deletions

diff --git a/drivers/usb/net/cdc_subset.c b/drivers/usb/net/cdc_subset.c
new file mode 100644
index 000000000000..f1730b685fd2
--- /dev/null
+++ b/drivers/usb/net/cdc_subset.c
@@ -0,0 +1,335 @@
+/*
+ * Simple "CDC Subset" USB Networking Links
+ * Copyright (C) 2000-2005 by David Brownell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/config.h>
+#ifdef  CONFIG_USB_DEBUG
+#   define DEBUG
+#endif
+#include <linux/module.h>
+#include <linux/kmod.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/workqueue.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+
+#include "usbnet.h"
+
+
+/*
+ * This supports simple USB network links that don't require any special
+ * framing or hardware control operations.  The protocol used here is a
+ * strict subset of CDC Ethernet, with three basic differences reflecting
+ * the goal that almost any hardware should run it:
+ *
+ *  - Minimal runtime control:  one interface, no altsettings, and
+ *    no vendor or class specific control requests.  If a device is
+ *    configured, it is allowed to exchange packets with the host.
+ *    Fancier models would mean not working on some hardware.
+ *
+ *  - Minimal manufacturing control:  no IEEE "Organizationally
+ *    Unique ID" required, or an EEPROMs to store one.  Each host uses
+ *    one random "locally assigned" Ethernet address instead, which can
+ *    of course be overridden using standard tools like "ifconfig".
+ *    (With 2^46 such addresses, same-net collisions are quite rare.)
+ *
+ *  - There is no additional framing data for USB.  Packets are written
+ *    exactly as in CDC Ethernet, starting with an Ethernet header and
+ *    terminated by a short packet.  However, the host will never send a
+ *    zero length packet; some systems can't handle those robustly.
+ *
+ * Anything that can transmit and receive USB bulk packets can implement
+ * this protocol.  That includes both smart peripherals and quite a lot
+ * of "host-to-host" USB cables (which embed two devices back-to-back).
+ *
+ * Note that although Linux may use many of those host-to-host links
+ * with this "cdc_subset" framing, that doesn't mean there may not be a
+ * better approach.  Handling the "other end unplugs/replugs" scenario
+ * well tends to require chip-specific vendor requests.  Also, Windows
+ * peers at the other end of host-to-host cables may expect their own
+ * framing to be used rather than this "cdc_subset" model.
+ */
+
+#if defined(CONFIG_USB_EPSON2888) || defined(CONFIG_USB_ARMLINUX)
+/* PDA style devices are always connected if present */
+static int always_connected (struct usbnet *dev)
+{
+        return 0;
+}
+#endif
+
+#ifdef  CONFIG_USB_ALI_M5632
+#define HAVE_HARDWARE
+
+/*-------------------------------------------------------------------------
+ *
+ * ALi M5632 driver ... does high speed
+ *
+ *-------------------------------------------------------------------------*/
+
+static const struct driver_info ali_m5632_info = {
+        .description =  "ALi M5632",
+};
+
+
+#endif
+
+
+#ifdef  CONFIG_USB_AN2720
+#define HAVE_HARDWARE
+
+/*-------------------------------------------------------------------------
+ *
+ * AnchorChips 2720 driver ... http://www.cypress.com
+ *
+ * This doesn't seem to have a way to detect whether the peer is
+ * connected, or need any reset handshaking.  It's got pretty big
+ * internal buffers (handles most of a frame's worth of data).
+ * Chip data sheets don't describe any vendor control messages.
+ *
+ *-------------------------------------------------------------------------*/
+
+static const struct driver_info an2720_info = {
+        .description =  "AnchorChips/Cypress 2720",
+        // no reset available!
+        // no check_connect available!
+
+        .in = 2, .out = 2,              // direction distinguishes these
+};
+
+#endif  /* CONFIG_USB_AN2720 */
+
+
+#ifdef  CONFIG_USB_BELKIN
+#define HAVE_HARDWARE
+
+/*-------------------------------------------------------------------------
+ *
+ * Belkin F5U104 ... two NetChip 2280 devices + Atmel AVR microcontroller
+ *
+ * ... also two eTEK designs, including one sold as "Advance USBNET"
+ *
+ *-------------------------------------------------------------------------*/
+
+static const struct driver_info belkin_info = {
+        .description =  "Belkin, eTEK, or compatible",
+};
+
+#endif  /* CONFIG_USB_BELKIN */
+
+
+
+#ifdef  CONFIG_USB_EPSON2888
+#define HAVE_HARDWARE
+
+/*-------------------------------------------------------------------------
+ *
+ * EPSON USB clients
+ *
+ * This is the same idea as Linux PDAs (below) except the firmware in the
+ * device might not be Tux-powered.  Epson provides reference firmware that
+ * implements this interface.  Product developers can reuse or modify that
+ * code, such as by using their own product and vendor codes.
+ *
+ * Support was from Juro Bystricky <bystricky.juro@erd.epson.com>
+ *
+ *-------------------------------------------------------------------------*/
+
+static const struct driver_info epson2888_info = {
+        .description =  "Epson USB Device",
+        .check_connect = always_connected,
+
+        .in = 4, .out = 3,
+};
+
+#endif  /* CONFIG_USB_EPSON2888 */
+
+
+#ifdef CONFIG_USB_KC2190
+#define HAVE_HARDWARE
+static const struct driver_info kc2190_info = {
+        .description =  "KC Technology KC-190",
+};
+#endif /* CONFIG_USB_KC2190 */
+
+
+#ifdef  CONFIG_USB_ARMLINUX
+#define HAVE_HARDWARE
+
+/*-------------------------------------------------------------------------
+ *
+ * Intel's SA-1100 chip integrates basic USB support, and is used
+ * in PDAs like some iPaqs, the Yopy, some Zaurus models, and more.
+ * When they run Linux, arch/arm/mach-sa1100/usb-eth.c may be used to
+ * network using minimal USB framing data.
+ *
+ * This describes the driver currently in standard ARM Linux kernels.
+ * The Zaurus uses a different driver (see later).
+ *
+ * PXA25x and PXA210 use XScale cores (ARM v5TE) with better USB support
+ * and different USB endpoint numbering than the SA1100 devices.  The
+ * mach-pxa/usb-eth.c driver re-uses the device ids from mach-sa1100
+ * so we rely on the endpoint descriptors.
+ *
+ *-------------------------------------------------------------------------*/
+
+static const struct driver_info linuxdev_info = {
+        .description =  "Linux Device",
+        .check_connect = always_connected,
+};
+
+static const struct driver_info yopy_info = {
+        .description =  "Yopy",
+        .check_connect = always_connected,
+};
+
+static const struct driver_info blob_info = {
+        .description =  "Boot Loader OBject",
+        .check_connect = always_connected,
+};
+
+#endif  /* CONFIG_USB_ARMLINUX */
+
+
+/*-------------------------------------------------------------------------*/
+
+#ifndef HAVE_HARDWARE
+#error You need to configure some hardware for this driver
+#endif
+
+/*
+ * chip vendor names won't normally be on the cables, and
+ * may not be on the device.
+ */
+
+static const struct usb_device_id       products [] = {
+
+#ifdef  CONFIG_USB_ALI_M5632
+{
+        USB_DEVICE (0x0402, 0x5632),    // ALi defaults
+        .driver_info =  (unsigned long) &ali_m5632_info,
+},
+#endif
+
+#ifdef  CONFIG_USB_AN2720
+{
+        USB_DEVICE (0x0547, 0x2720),    // AnchorChips defaults
+        .driver_info =  (unsigned long) &an2720_info,
+}, {
+        USB_DEVICE (0x0547, 0x2727),    // Xircom PGUNET
+        .driver_info =  (unsigned long) &an2720_info,
+},
+#endif
+
+#ifdef  CONFIG_USB_BELKIN
+{
+        USB_DEVICE (0x050d, 0x0004),    // Belkin
+        .driver_info =  (unsigned long) &belkin_info,
+}, {
+        USB_DEVICE (0x056c, 0x8100),    // eTEK
+        .driver_info =  (unsigned long) &belkin_info,
+}, {
+        USB_DEVICE (0x0525, 0x9901),    // Advance USBNET (eTEK)
+        .driver_info =  (unsigned long) &belkin_info,
+},
+#endif
+
+#ifdef  CONFIG_USB_EPSON2888
+{
+        USB_DEVICE (0x0525, 0x2888),    // EPSON USB client
+        .driver_info    = (unsigned long) &epson2888_info,
+},
+#endif
+
+#ifdef CONFIG_USB_KC2190
+{
+        USB_DEVICE (0x050f, 0x0190),    // KC-190
+        .driver_info =  (unsigned long) &kc2190_info,
+},
+#endif
+
+#ifdef  CONFIG_USB_ARMLINUX
+/*
+ * SA-1100 using standard ARM Linux kernels, or compatible.
+ * Often used when talking to Linux PDAs (iPaq, Yopy, etc).
+ * The sa-1100 "usb-eth" driver handles the basic framing.
+ *
+ * PXA25x or PXA210 ...  these use a "usb-eth" driver much like
+ * the sa1100 one, but hardware uses different endpoint numbers.
+ *
+ * Or the Linux "Ethernet" gadget on hardware that can't talk
+ * CDC Ethernet (e.g., no altsettings), in either of two modes:
+ *  - acting just like the old "usb-eth" firmware, though
+ *    the implementation is different
+ *  - supporting RNDIS as the first/default configuration for
+ *    MS-Windows interop; Linux needs to use the other config
+ */
+{
+        // 1183 = 0x049F, both used as hex values?
+        // Compaq "Itsy" vendor/product id
+        USB_DEVICE (0x049F, 0x505A),    // usb-eth, or compatible
+        .driver_info =  (unsigned long) &linuxdev_info,
+}, {
+        USB_DEVICE (0x0E7E, 0x1001),    // G.Mate "Yopy"
+        .driver_info =  (unsigned long) &yopy_info,
+}, {
+        USB_DEVICE (0x8086, 0x07d3),    // "blob" bootloader
+        .driver_info =  (unsigned long) &blob_info,
+}, {
+        // Linux Ethernet/RNDIS gadget on pxa210/25x/26x, second config
+        // e.g. Gumstix, current OpenZaurus, ...
+        USB_DEVICE_VER (0x0525, 0xa4a2, 0x0203, 0x0203),
+        .driver_info =  (unsigned long) &linuxdev_info,
+},
+#endif
+
+        { },            // END
+};
+MODULE_DEVICE_TABLE(usb, products);
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_driver cdc_subset_driver = {
+        .owner =        THIS_MODULE,
+        .name =         "cdc_subset",
+        .probe =        usbnet_probe,
+        .suspend =      usbnet_suspend,
+        .resume =       usbnet_resume,
+        .disconnect =   usbnet_disconnect,
+        .id_table =     products,
+};
+
+static int __init cdc_subset_init(void)
+{
+        return usb_register(&cdc_subset_driver);
+}
+module_init(cdc_subset_init);
+
+static void __exit cdc_subset_exit(void)
+{
+        usb_deregister(&cdc_subset_driver);
+}
+module_exit(cdc_subset_exit);
+
+MODULE_AUTHOR("David Brownell");
+MODULE_DESCRIPTION("Simple 'CDC Subset' USB networking links");
+MODULE_LICENSE("GPL");