// SPDX-License-Identifier: GPL-2.0-or-later/* * Simple "CDC Subset" USB Networking Links * Copyright (C) 2000-2005 by David Brownell */ #include <linux/module.h>#include <linux/kmod.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 <linux/usb/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 * * NOTE that the MS-Windows drivers for this chip use some funky and * (naturally) undocumented 7-byte prefix to each packet, so this is a * case where we don't currently interoperate.  Also, once you unplug * one end of the cable, you need to replug the other end too ... since * chip docs are unavailable, there's no way to reset the relevant state * short of a power cycle. * *-------------------------------------------------------------------------*/ static void m5632_recover(struct usbnet *dev){	struct usb_device	*udev = dev->udev;	struct usb_interface	*intf = dev->intf;	int r; 	r = usb_lock_device_for_reset(udev, intf);	if (r < 0)		return; 	usb_reset_device(udev);	usb_unlock_device(udev);} static const struct driver_info	ali_m5632_info = {	.description =	"ALi M5632",	.flags       = FLAG_POINTTOPOINT,	.recover     = m5632_recover,}; #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",	.flags       = FLAG_POINTTOPOINT,	// 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",	.flags       = FLAG_POINTTOPOINT,}; #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,	.flags = FLAG_POINTTOPOINT, 	.in = 4, .out = 3,}; #endif	/* CONFIG_USB_EPSON2888 */  /*------------------------------------------------------------------------- * * info from Jonathan McDowell <noodles@earth.li> * *-------------------------------------------------------------------------*/#ifdef CONFIG_USB_KC2190#define HAVE_HARDWAREstatic const struct driver_info kc2190_info = {	.description =  "KC Technology KC-190",	.flags = FLAG_POINTTOPOINT,};#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,	.flags = FLAG_POINTTOPOINT,}; static const struct driver_info	yopy_info = {	.description =	"Yopy",	.check_connect = always_connected,	.flags = FLAG_POINTTOPOINT,}; static const struct driver_info	blob_info = {	.description =	"Boot Loader OBject",	.check_connect = always_connected,	.flags = FLAG_POINTTOPOINT,}; #endif	/* CONFIG_USB_ARMLINUX */  /*-------------------------------------------------------------------------*/ #ifndef	HAVE_HARDWARE#warning 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,},{	USB_DEVICE (0x182d,0x207c),	// SiteCom CN-124	.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,}, {	USB_DEVICE (0x1286, 0x8001),    // "blob" bootloader	.driver_info =  (unsigned long) &blob_info,}, {	// Linux Ethernet/RNDIS gadget, mostly on PXA, second config	// e.g. Gumstix, current OpenZaurus, ... or anything else	// that just enables this gadget option.	USB_DEVICE (0x0525, 0xa4a2),	.driver_info =	(unsigned long) &linuxdev_info,},#endif 	{ },		// END};MODULE_DEVICE_TABLE(usb, products); /*-------------------------------------------------------------------------*/static int dummy_prereset(struct usb_interface *intf){        return 0;} static int dummy_postreset(struct usb_interface *intf){        return 0;} static struct usb_driver cdc_subset_driver = {	.name =		"cdc_subset",	.probe =	usbnet_probe,	.suspend =	usbnet_suspend,	.resume =	usbnet_resume,	.pre_reset =	dummy_prereset,	.post_reset =	dummy_postreset,	.disconnect =	usbnet_disconnect,	.id_table =	products,	.disable_hub_initiated_lpm = 1,}; module_usb_driver(cdc_subset_driver); MODULE_AUTHOR("David Brownell");MODULE_DESCRIPTION("Simple 'CDC Subset' USB networking links");MODULE_LICENSE("GPL");