linux/drivers/usb/gadget/ether.c

487 lines
13 KiB
C

/*
* 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/netdevice.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
}
#include <linux/module.h>
#include "u_ecm.h"
#include "u_gether.h"
#ifdef USB_ETH_RNDIS
#include "u_rndis.h"
#include "rndis.h"
#else
#define rndis_borrow_net(...) do {} while (0)
#endif
#include "u_eem.h"
/*-------------------------------------------------------------------------*/
USB_GADGET_COMPOSITE_OPTIONS();
USB_ETHERNET_MODULE_PARAMETERS();
/* 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,
};
static struct usb_string strings_dev[] = {
[USB_GADGET_MANUFACTURER_IDX].s = "",
[USB_GADGET_PRODUCT_IDX].s = PREFIX DRIVER_DESC,
[USB_GADGET_SERIAL_IDX].s = "",
{ } /* 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 struct usb_function_instance *fi_ecm;
static struct usb_function *f_ecm;
static struct usb_function_instance *fi_eem;
static struct usb_function *f_eem;
static struct usb_function_instance *fi_geth;
static struct usb_function *f_geth;
static struct usb_function_instance *fi_rndis;
static struct usb_function *f_rndis;
/*-------------------------------------------------------------------------*/
/*
* 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)
{
int status;
/* 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;
}
f_rndis = usb_get_function(fi_rndis);
if (IS_ERR(f_rndis))
return PTR_ERR(f_rndis);
status = usb_add_function(c, f_rndis);
if (status < 0)
usb_put_function(f_rndis);
return status;
}
static struct usb_configuration rndis_config_driver = {
.label = "RNDIS",
.bConfigurationValue = 2,
/* .iConfiguration = DYNAMIC */
.bmAttributes = USB_CONFIG_ATT_SELFPOWER,
};
/*-------------------------------------------------------------------------*/
#ifdef CONFIG_USB_ETH_EEM
static bool use_eem = 1;
#else
static bool 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)
{
int status = 0;
/* 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) {
f_eem = usb_get_function(fi_eem);
if (IS_ERR(f_eem))
return PTR_ERR(f_eem);
status = usb_add_function(c, f_eem);
if (status < 0)
usb_put_function(f_eem);
return status;
} else if (can_support_ecm(c->cdev->gadget)) {
f_ecm = usb_get_function(fi_ecm);
if (IS_ERR(f_ecm))
return PTR_ERR(f_ecm);
status = usb_add_function(c, f_ecm);
if (status < 0)
usb_put_function(f_ecm);
return status;
} else {
f_geth = usb_get_function(fi_geth);
if (IS_ERR(f_geth))
return PTR_ERR(f_geth);
status = usb_add_function(c, f_geth);
if (status < 0)
usb_put_function(f_geth);
return status;
}
}
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)
{
struct usb_gadget *gadget = cdev->gadget;
struct f_eem_opts *eem_opts = NULL;
struct f_ecm_opts *ecm_opts = NULL;
struct f_gether_opts *geth_opts = NULL;
struct net_device *net;
int status;
/* set up main config label and device descriptor */
if (use_eem) {
/* EEM */
fi_eem = usb_get_function_instance("eem");
if (IS_ERR(fi_eem))
return PTR_ERR(fi_eem);
eem_opts = container_of(fi_eem, struct f_eem_opts, func_inst);
net = eem_opts->net;
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(gadget)) {
/* ECM */
fi_ecm = usb_get_function_instance("ecm");
if (IS_ERR(fi_ecm))
return PTR_ERR(fi_ecm);
ecm_opts = container_of(fi_ecm, struct f_ecm_opts, func_inst);
net = ecm_opts->net;
eth_config_driver.label = "CDC Ethernet (ECM)";
} else {
/* CDC Subset */
fi_geth = usb_get_function_instance("geth");
if (IS_ERR(fi_geth))
return PTR_ERR(fi_geth);
geth_opts = container_of(fi_geth, struct f_gether_opts,
func_inst);
net = geth_opts->net;
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;
}
gether_set_qmult(net, qmult);
if (!gether_set_host_addr(net, host_addr))
pr_info("using host ethernet address: %s", host_addr);
if (!gether_set_dev_addr(net, dev_addr))
pr_info("using self ethernet address: %s", dev_addr);
if (has_rndis()) {
/* RNDIS plus ECM-or-Subset */
gether_set_gadget(net, cdev->gadget);
status = gether_register_netdev(net);
if (status)
goto fail;
if (use_eem)
eem_opts->bound = true;
else if (can_support_ecm(gadget))
ecm_opts->bound = true;
else
geth_opts->bound = true;
fi_rndis = usb_get_function_instance("rndis");
if (IS_ERR(fi_rndis)) {
status = PTR_ERR(fi_rndis);
goto fail;
}
rndis_borrow_net(fi_rndis, net);
device_desc.idVendor = cpu_to_le16(RNDIS_VENDOR_NUM);
device_desc.idProduct = cpu_to_le16(RNDIS_PRODUCT_NUM);
device_desc.bNumConfigurations = 2;
}
/* Allocate string descriptor numbers ... note that string
* contents can be overridden by the composite_dev glue.
*/
status = usb_string_ids_tab(cdev, strings_dev);
if (status < 0)
goto fail1;
device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
/* 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 fail1;
}
status = usb_add_config(cdev, &eth_config_driver, eth_do_config);
if (status < 0)
goto fail1;
usb_composite_overwrite_options(cdev, &coverwrite);
dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n",
DRIVER_DESC);
return 0;
fail1:
if (has_rndis())
usb_put_function_instance(fi_rndis);
fail:
if (use_eem)
usb_put_function_instance(fi_eem);
else if (can_support_ecm(gadget))
usb_put_function_instance(fi_ecm);
else
usb_put_function_instance(fi_geth);
return status;
}
static int __exit eth_unbind(struct usb_composite_dev *cdev)
{
if (has_rndis())
usb_put_function_instance(fi_rndis);
if (use_eem)
usb_put_function_instance(fi_eem);
else if (can_support_ecm(cdev->gadget))
usb_put_function_instance(fi_ecm);
else
usb_put_function_instance(fi_geth);
return 0;
}
static __refdata struct usb_composite_driver eth_driver = {
.name = "g_ether",
.dev = &device_desc,
.strings = dev_strings,
.max_speed = USB_SPEED_SUPER,
.bind = eth_bind,
.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(&eth_driver);
}
module_init(init);
static void __exit cleanup(void)
{
usb_composite_unregister(&eth_driver);
}
module_exit(cleanup);