/* * ether.c -- Ethernet gadget driver, with CDC and non-CDC options * * Copyright (C) 2003-2005,2008 David Brownell * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger * Copyright (C) 2008 Nokia Corporation * * 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. */ /* #define VERBOSE_DEBUG */ #include <linux/kernel.h> #include <linux/utsname.h> #if defined USB_ETH_RNDIS # undef USB_ETH_RNDIS #endif #ifdef CONFIG_USB_ETH_RNDIS # define USB_ETH_RNDIS y #endif #include "u_ether.h" /* * Ethernet gadget driver -- with CDC and non-CDC options * Builds on hardware support for a full duplex link. * * CDC Ethernet is the standard USB solution for sending Ethernet frames * using USB. Real hardware tends to use the same framing protocol but look * different for control features. This driver strongly prefers to use * this USB-IF standard as its open-systems interoperability solution; * most host side USB stacks (except from Microsoft) support it. * * This is sometimes called "CDC ECM" (Ethernet Control Model) to support * TLA-soup. "CDC ACM" (Abstract Control Model) is for modems, and a new * "CDC EEM" (Ethernet Emulation Model) is starting to spread. * * There's some hardware that can't talk CDC ECM. We make that hardware * implement a "minimalist" vendor-agnostic CDC core: same framing, but * link-level setup only requires activating the configuration. Only the * endpoint descriptors, and product/vendor IDs, are relevant; no control * operations are available. Linux supports it, but other host operating * systems may not. (This is a subset of CDC Ethernet.) * * It turns out that if you add a few descriptors to that "CDC Subset", * (Windows) host side drivers from MCCI can treat it as one submode of * a proprietary scheme called "SAFE" ... without needing to know about * specific product/vendor IDs. So we do that, making it easier to use * those MS-Windows drivers. Those added descriptors make it resemble a * CDC MDLM device, but they don't change device behavior at all. (See * MCCI Engineering report 950198 "SAFE Networking Functions".) * * A third option is also in use. Rather than CDC Ethernet, or something * simpler, Microsoft pushes their own approach: RNDIS. The published * RNDIS specs are ambiguous and appear to be incomplete, and are also * needlessly complex. They borrow more from CDC ACM than CDC ECM. */ #define DRIVER_DESC "Ethernet Gadget" #define DRIVER_VERSION "Memorial Day 2008" #ifdef USB_ETH_RNDIS #define PREFIX "RNDIS/" #else #define PREFIX "" #endif /* * This driver aims for interoperability by using CDC ECM unless * * can_support_ecm() * * returns false, in which case it supports the CDC Subset. By default, * that returns true; most hardware has no problems with CDC ECM, that's * a good default. Previous versions of this driver had no default; this * version changes that, removing overhead for new controller support. * * IF YOUR HARDWARE CAN'T SUPPORT CDC ECM, UPDATE THAT ROUTINE! */ static inline bool has_rndis(void) { #ifdef USB_ETH_RNDIS return true; #else return false; #endif } /*-------------------------------------------------------------------------*/ /* * Kbuild is not very cooperative with respect to linking separately * compiled library objects into one module. So for now we won't use * separate compilation ... ensuring init/exit sections work to shrink * the runtime footprint, and giving us at least some parts of what * a "gcc --combine ... part1.c part2.c part3.c ... " build would. */ #include "composite.c" #include "usbstring.c" #include "config.c" #include "epautoconf.c" #include "f_ecm.c" #include "f_subset.c" #ifdef USB_ETH_RNDIS #include "f_rndis.c" #include "rndis.c" #endif #include "f_eem.c" #include "u_ether.c" /*-------------------------------------------------------------------------*/ /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!! * Instead: allocate your own, using normal USB-IF procedures. */ /* Thanks to NetChip Technologies for donating this product ID. * It's for devices with only CDC Ethernet configurations. */ #define CDC_VENDOR_NUM 0x0525 /* NetChip */ #define CDC_PRODUCT_NUM 0xa4a1 /* Linux-USB Ethernet Gadget */ /* For hardware that can't talk CDC, we use the same vendor ID that * ARM Linux has used for ethernet-over-usb, both with sa1100 and * with pxa250. We're protocol-compatible, if the host-side drivers * use the endpoint descriptors. bcdDevice (version) is nonzero, so * drivers that need to hard-wire endpoint numbers have a hook. * * The protocol is a minimal subset of CDC Ether, which works on any bulk * hardware that's not deeply broken ... even on hardware that can't talk * RNDIS (like SA-1100, with no interrupt endpoint, or anything that * doesn't handle control-OUT). */ #define SIMPLE_VENDOR_NUM 0x049f #define SIMPLE_PRODUCT_NUM 0x505a /* For hardware that can talk RNDIS and either of the above protocols, * use this ID ... the windows INF files will know it. Unless it's * used with CDC Ethernet, Linux 2.4 hosts will need updates to choose * the non-RNDIS configuration. */ #define RNDIS_VENDOR_NUM 0x0525 /* NetChip */ #define RNDIS_PRODUCT_NUM 0xa4a2 /* Ethernet/RNDIS Gadget */ /* For EEM gadgets */ #define EEM_VENDOR_NUM 0x1d6b /* Linux Foundation */ #define EEM_PRODUCT_NUM 0x0102 /* EEM Gadget */ /*-------------------------------------------------------------------------*/ static struct usb_device_descriptor device_desc = { .bLength = sizeof device_desc, .bDescriptorType = USB_DT_DEVICE, .bcdUSB = cpu_to_le16 (0x0200), .bDeviceClass = USB_CLASS_COMM, .bDeviceSubClass = 0, .bDeviceProtocol = 0, /* .bMaxPacketSize0 = f(hardware) */ /* Vendor and product id defaults change according to what configs * we support. (As does bNumConfigurations.) These values can * also be overridden by module parameters. */ .idVendor = cpu_to_le16 (CDC_VENDOR_NUM), .idProduct = cpu_to_le16 (CDC_PRODUCT_NUM), /* .bcdDevice = f(hardware) */ /* .iManufacturer = DYNAMIC */ /* .iProduct = DYNAMIC */ /* NO SERIAL NUMBER */ .bNumConfigurations = 1, }; static struct usb_otg_descriptor otg_descriptor = { .bLength = sizeof otg_descriptor, .bDescriptorType = USB_DT_OTG, /* REVISIT SRP-only hardware is possible, although * it would not be called "OTG" ... */ .bmAttributes = USB_OTG_SRP | USB_OTG_HNP, }; static const struct usb_descriptor_header *otg_desc[] = { (struct usb_descriptor_header *) &otg_descriptor, NULL, }; /* string IDs are assigned dynamically */ #define STRING_MANUFACTURER_IDX 0 #define STRING_PRODUCT_IDX 1 static char manufacturer[50]; static struct usb_string strings_dev[] = { [STRING_MANUFACTURER_IDX].s = manufacturer, [STRING_PRODUCT_IDX].s = PREFIX DRIVER_DESC, { } /* end of list */ }; static struct usb_gadget_strings stringtab_dev = { .language = 0x0409, /* en-us */ .strings = strings_dev, }; static struct usb_gadget_strings *dev_strings[] = { &stringtab_dev, NULL, }; static u8 hostaddr[ETH_ALEN]; /*-------------------------------------------------------------------------*/ /* * We may not have an RNDIS configuration, but if we do it needs to be * the first one present. That's to make Microsoft's drivers happy, * and to follow DOCSIS 1.0 (cable modem standard). */ static int __init rndis_do_config(struct usb_configuration *c) { /* FIXME alloc iConfiguration string, set it in c->strings */ if (gadget_is_otg(c->cdev->gadget)) { c->descriptors = otg_desc; c->bmAttributes |= USB_CONFIG_ATT_WAKEUP; } return rndis_bind_config(c, hostaddr); } static struct usb_configuration rndis_config_driver = { .label = "RNDIS", .bConfigurationValue = 2, /* .iConfiguration = DYNAMIC */ .bmAttributes = USB_CONFIG_ATT_SELFPOWER, }; /*-------------------------------------------------------------------------*/ #ifdef CONFIG_USB_ETH_EEM static int use_eem = 1; #else static int use_eem; #endif module_param(use_eem, bool, 0); MODULE_PARM_DESC(use_eem, "use CDC EEM mode"); /* * We _always_ have an ECM, CDC Subset, or EEM configuration. */ static int __init eth_do_config(struct usb_configuration *c) { /* FIXME alloc iConfiguration string, set it in c->strings */ if (gadget_is_otg(c->cdev->gadget)) { c->descriptors = otg_desc; c->bmAttributes |= USB_CONFIG_ATT_WAKEUP; } if (use_eem) return eem_bind_config(c); else if (can_support_ecm(c->cdev->gadget)) return ecm_bind_config(c, hostaddr); else return geth_bind_config(c, hostaddr); } static struct usb_configuration eth_config_driver = { /* .label = f(hardware) */ .bConfigurationValue = 1, /* .iConfiguration = DYNAMIC */ .bmAttributes = USB_CONFIG_ATT_SELFPOWER, }; /*-------------------------------------------------------------------------*/ static int __init eth_bind(struct usb_composite_dev *cdev) { int gcnum; struct usb_gadget *gadget = cdev->gadget; int status; /* set up network link layer */ status = gether_setup(cdev->gadget, hostaddr); if (status < 0) return status; /* set up main config label and device descriptor */ if (use_eem) { /* EEM */ eth_config_driver.label = "CDC Ethernet (EEM)"; device_desc.idVendor = cpu_to_le16(EEM_VENDOR_NUM); device_desc.idProduct = cpu_to_le16(EEM_PRODUCT_NUM); } else if (can_support_ecm(cdev->gadget)) { /* ECM */ eth_config_driver.label = "CDC Ethernet (ECM)"; } else { /* CDC Subset */ eth_config_driver.label = "CDC Subset/SAFE"; device_desc.idVendor = cpu_to_le16(SIMPLE_VENDOR_NUM); device_desc.idProduct = cpu_to_le16(SIMPLE_PRODUCT_NUM); if (!has_rndis()) device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC; } if (has_rndis()) { /* RNDIS plus ECM-or-Subset */ device_desc.idVendor = cpu_to_le16(RNDIS_VENDOR_NUM); device_desc.idProduct = cpu_to_le16(RNDIS_PRODUCT_NUM); device_desc.bNumConfigurations = 2; } gcnum = usb_gadget_controller_number(gadget); if (gcnum >= 0) device_desc.bcdDevice = cpu_to_le16(0x0300 | gcnum); else { /* We assume that can_support_ecm() tells the truth; * but if the controller isn't recognized at all then * that assumption is a bit more likely to be wrong. */ dev_warn(&gadget->dev, "controller '%s' not recognized; trying %s\n", gadget->name, eth_config_driver.label); device_desc.bcdDevice = cpu_to_le16(0x0300 | 0x0099); } /* Allocate string descriptor numbers ... note that string * contents can be overridden by the composite_dev glue. */ /* device descriptor strings: manufacturer, product */ snprintf(manufacturer, sizeof manufacturer, "%s %s with %s", init_utsname()->sysname, init_utsname()->release, gadget->name); status = usb_string_id(cdev); if (status < 0) goto fail; strings_dev[STRING_MANUFACTURER_IDX].id = status; device_desc.iManufacturer = status; status = usb_string_id(cdev); if (status < 0) goto fail; strings_dev[STRING_PRODUCT_IDX].id = status; device_desc.iProduct = status; /* register our configuration(s); RNDIS first, if it's used */ if (has_rndis()) { status = usb_add_config(cdev, &rndis_config_driver, rndis_do_config); if (status < 0) goto fail; } status = usb_add_config(cdev, ð_config_driver, eth_do_config); if (status < 0) goto fail; dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n", DRIVER_DESC); return 0; fail: gether_cleanup(); return status; } static int __exit eth_unbind(struct usb_composite_dev *cdev) { gether_cleanup(); return 0; } static struct usb_composite_driver eth_driver = { .name = "g_ether", .dev = &device_desc, .strings = dev_strings, .max_speed = USB_SPEED_SUPER, .unbind = __exit_p(eth_unbind), }; MODULE_DESCRIPTION(PREFIX DRIVER_DESC); MODULE_AUTHOR("David Brownell, Benedikt Spanger"); MODULE_LICENSE("GPL"); static int __init init(void) { return usb_composite_probe(ð_driver, eth_bind); } module_init(init); static void __exit cleanup(void) { usb_composite_unregister(ð_driver); } module_exit(cleanup);