ether.c

h内核

/*
 * ether.c -- Ethernet gadget driver, with CDC and non-CDC options
 *
 * Copyright (C) 2003-2004 David Brownell
 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
 *
 * 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
 */


// #define DEBUG 1
// #define VERBOSE

#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/timer.h>
#include <linux/list.h>
#include <linux/interrupt.h>
#include <linux/utsname.h>
#include <linux/device.h>
#include <linux/moduleparam.h>
#include <linux/ctype.h>

#include <asm/byteorder.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/unaligned.h>

#include <linux/usb_ch9.h>
#include <linux/usb_gadget.h>

#include <linux/random.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>

#include "gadget_chips.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.
 *
 * There's some hardware that can't talk CDC.  We make that hardware
 * implement a "minimalist" vendor-agnostic CDC core:  same framing, but
 * link-level setup only requires activating the configuration.
 * Linux supports it, but other host operating systems may not.
 * (This is a subset of CDC Ethernet.)
 *
 * 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.
 */

#define DRIVER_DESC		"Ethernet Gadget"
#define DRIVER_VERSION		"Equinox 2004"

static const char shortname [] = "ether";
static const char driver_desc [] = DRIVER_DESC;

#define RX_EXTRA	20		/* guard against rx overflows */

#ifdef	CONFIG_USB_ETH_RNDIS
#include "rndis.h"
#else
#define rndis_init() 0
#define rndis_exit() do{}while(0)
#endif

/*-------------------------------------------------------------------------*/

struct eth_dev {
	spinlock_t		lock;
	struct usb_gadget	*gadget;
	struct usb_request	*req;		/* for control responses */

	u8			config;
	struct usb_ep		*in_ep, *out_ep, *status_ep;
	const struct usb_endpoint_descriptor
				*in, *out, *status;
	struct list_head	tx_reqs, rx_reqs;

	struct net_device	*net;
	struct net_device_stats	stats;
	atomic_t		tx_qlen;

	struct work_struct	work;
	unsigned		zlp:1;
	unsigned		cdc:1;
	unsigned		rndis:1;
	unsigned		suspended:1;
	u16			cdc_filter;
	unsigned long		todo;
#define	WORK_RX_MEMORY		0
	int			rndis_config;
	u8			host_mac [ETH_ALEN];
};

/* This version autoconfigures as much as possible at run-time.
 *
 * It also ASSUMES a self-powered device, without remote wakeup,
 * although remote wakeup support would make sense.
 */
static const char *EP_IN_NAME;
static const char *EP_OUT_NAME;
static const char *EP_STATUS_NAME;

/*-------------------------------------------------------------------------*/

/* 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 */


/* Some systems will want different product identifers published in the
 * device descriptor, either numbers or strings or both.  These string
 * parameters are in UTF-8 (superset of ASCII's 7 bit characters).
 */

static ushort __initdata idVendor;
module_param(idVendor, ushort, S_IRUGO);
MODULE_PARM_DESC(idVendor, "USB Vendor ID");

static ushort __initdata idProduct;
module_param(idProduct, ushort, S_IRUGO);
MODULE_PARM_DESC(idProduct, "USB Product ID");

static ushort __initdata bcdDevice;
module_param(bcdDevice, ushort, S_IRUGO);
MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)");

static char *__initdata iManufacturer;
module_param(iManufacturer, charp, S_IRUGO);
MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string");

static char *__initdata iProduct;
module_param(iProduct, charp, S_IRUGO);
MODULE_PARM_DESC(iProduct, "USB Product string");

/* initial value, changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx" */
static char *__initdata dev_addr;
module_param(dev_addr, charp, S_IRUGO);
MODULE_PARM_DESC(iProduct, "Device Ethernet Address");

/* this address is invisible to ifconfig */
static char *__initdata host_addr;
module_param(host_addr, charp, S_IRUGO);
MODULE_PARM_DESC(host_addr, "Host Ethernet Address");


/*-------------------------------------------------------------------------*/

/* Include CDC support if we could run on CDC-capable hardware. */

#ifdef CONFIG_USB_GADGET_NET2280
#define	DEV_CONFIG_CDC
#endif

#ifdef CONFIG_USB_GADGET_DUMMY_HCD
#define	DEV_CONFIG_CDC
#endif

#ifdef CONFIG_USB_GADGET_GOKU
#define	DEV_CONFIG_CDC
#endif

#ifdef CONFIG_USB_GADGET_LH7A40X
#define DEV_CONFIG_CDC
#endif

#ifdef CONFIG_USB_GADGET_MQ11XX
#define	DEV_CONFIG_CDC
#endif

#ifdef CONFIG_USB_GADGET_OMAP
#define	DEV_CONFIG_CDC
#endif

#ifdef CONFIG_USB_GADGET_N9604
#define	DEV_CONFIG_CDC
#endif

#ifdef CONFIG_USB_GADGET_PXA27X
#define DEV_CONFIG_CDC
#endif


/* For CDC-incapable hardware, choose the simple cdc subset.
 * Anything that talks bulk (without notable bugs) can do this.
 */
#ifdef CONFIG_USB_GADGET_PXA2XX
#define	DEV_CONFIG_SUBSET
#endif

#ifdef CONFIG_USB_GADGET_SH
#define	DEV_CONFIG_SUBSET
#endif

#ifdef CONFIG_USB_GADGET_SA1100
/* use non-CDC for backwards compatibility */
#define	DEV_CONFIG_SUBSET
#endif


/*-------------------------------------------------------------------------*/

#define DEFAULT_QLEN	2	/* double buffering by default */

#ifdef CONFIG_USB_GADGET_DUALSPEED

static unsigned qmult = 5;
module_param (qmult, uint, S_IRUGO|S_IWUSR);


/* for dual-speed hardware, use deeper queues at highspeed */
#define qlen(gadget) \
	(DEFAULT_QLEN*((gadget->speed == USB_SPEED_HIGH) ? qmult : 1))

/* also defer IRQs on highspeed TX */
#define TX_DELAY	qmult

#define	BITRATE(g) ((g->speed == USB_SPEED_HIGH) ? 4800000 : 120000)

#else	/* full speed (low speed doesn't do bulk) */
#define qlen(gadget) DEFAULT_QLEN

#define	BITRATE(g)	(12000)
#endif


/*-------------------------------------------------------------------------*/

#define xprintk(d,level,fmt,args...) \
	printk(level "%s: " fmt , (d)->net->name , ## args)

#ifdef DEBUG
#undef DEBUG
#define DEBUG(dev,fmt,args...) \
	xprintk(dev , KERN_DEBUG , fmt , ## args)
#else
#define DEBUG(dev,fmt,args...) \
	do { } while (0)
#endif /* DEBUG */

#ifdef VERBOSE
#define VDEBUG	DEBUG
#else
#define VDEBUG(dev,fmt,args...) \
	do { } while (0)
#endif /* DEBUG */

#define ERROR(dev,fmt,args...) \
	xprintk(dev , KERN_ERR , fmt , ## args)
#define WARN(dev,fmt,args...) \
	xprintk(dev , KERN_WARNING , fmt , ## args)
#define INFO(dev,fmt,args...) \
	xprintk(dev , KERN_INFO , fmt , ## args)

/*-------------------------------------------------------------------------*/

/* USB DRIVER HOOKUP (to the hardware driver, below us), mostly
 * ep0 implementation:  descriptors, config management, setup().
 * also optional class-specific notification interrupt transfer.
 */

/*
 * DESCRIPTORS ... most are static, but strings and (full) configuration
 * descriptors are built on demand.  For now we do either full CDC, or
 * our simple subset, with RNDIS as an optional second configuration.
 *
 * RNDIS includes some CDC ACM descriptors ... like CDC Ethernet.  But
 * the class descriptors match a modem (they're ignored; it's really just
 * Ethernet functionality), they don't need the NOP altsetting, and the
 * status transfer endpoint isn't optional.
 */

#define STRING_MANUFACTURER		1
#define STRING_PRODUCT			2
#define STRING_ETHADDR			3
#define STRING_DATA			4
#define STRING_CONTROL			5
#define STRING_RNDIS_CONTROL		6
#define STRING_CDC			7
#define STRING_SUBSET			8
#define STRING_RNDIS			9

#define USB_BUFSIZ	256		/* holds our biggest descriptor */

/*
 * This device advertises one configuration, eth_config, unless RNDIS
 * is enabled (rndis_config) on hardware supporting at least two configs.
 *
 * NOTE:  Controllers like superh_udc should probably be able to use
 * an RNDIS-only configuration.
 *
 * FIXME define some higher-powered configurations to make it easier
 * to recharge batteries ...
 */

#define DEV_CONFIG_VALUE	1	/* cdc or subset */
#define DEV_RNDIS_CONFIG_VALUE	2	/* rndis; optional */

static struct usb_device_descriptor
device_desc = {
	.bLength =		sizeof device_desc,
	.bDescriptorType =	USB_DT_DEVICE,

	.bcdUSB =		__constant_cpu_to_le16 (0x0200),

	.bDeviceClass =		USB_CLASS_COMM,
	.bDeviceSubClass =	0,
	.bDeviceProtocol =	0,

	.idVendor =		__constant_cpu_to_le16 (CDC_VENDOR_NUM),
	.idProduct =		__constant_cpu_to_le16 (CDC_PRODUCT_NUM),
	.iManufacturer =	STRING_MANUFACTURER,
	.iProduct =		STRING_PRODUCT,
	.bNumConfigurations =	1,
};

static struct usb_otg_descriptor
otg_descriptor = {
	.bLength =		sizeof otg_descriptor,
	.bDescriptorType =	USB_DT_OTG,

	.bmAttributes =		USB_OTG_SRP,
};

static struct usb_config_descriptor
eth_config = {
	.bLength =		sizeof eth_config,
	.bDescriptorType =	USB_DT_CONFIG,

	/* compute wTotalLength on the fly */
	.bNumInterfaces =	2,
	.bConfigurationValue =	DEV_CONFIG_VALUE,
	.iConfiguration =	STRING_CDC,
	.bmAttributes =		USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
	.bMaxPower =		50,
};

#ifdef	CONFIG_USB_ETH_RNDIS
static struct usb_config_descriptor 
rndis_config = {
	.bLength =              sizeof rndis_config,
	.bDescriptorType =      USB_DT_CONFIG,

	/* compute wTotalLength on the fly */
	.bNumInterfaces =       2,
	.bConfigurationValue =  DEV_RNDIS_CONFIG_VALUE,
	.iConfiguration =       STRING_RNDIS,
	.bmAttributes =		USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
	.bMaxPower =            50,
};
#endif

/*
 * Compared to the simple CDC subset, the full CDC Ethernet model adds
 * three class descriptors, two interface descriptors, optional status
 * endpoint.  Both have a "data" interface and two bulk endpoints.
 * There are also differences in how control requests are handled.
 *
 * RNDIS shares a lot with CDC-Ethernet, since it's a variant of
 * the CDC-ACM (modem) spec.
 */

#ifdef	DEV_CONFIG_CDC
static struct usb_interface_descriptor
control_intf = {
	.bLength =		sizeof control_intf,
	.bDescriptorType =	USB_DT_INTERFACE,

	.bInterfaceNumber =	0,
	/* status endpoint is optional; this may be patched later */
	.bNumEndpoints =	1,
	.bInterfaceClass =	USB_CLASS_COMM,
	.bInterfaceSubClass =	6,	/* ethernet control model */
	.bInterfaceProtocol =	0,
	.iInterface =		STRING_CONTROL,
};
#endif

#ifdef	CONFIG_USB_ETH_RNDIS
static const struct usb_interface_descriptor
rndis_control_intf = {
	.bLength =              sizeof rndis_control_intf,
	.bDescriptorType =      USB_DT_INTERFACE,
	  
	.bInterfaceNumber =     0,
	.bNumEndpoints =        1,
	.bInterfaceClass =      USB_CLASS_COMM,
	.bInterfaceSubClass =   2,	/* abstract control model */
	.bInterfaceProtocol =   0xff,	/* vendor specific */
	.iInterface =           STRING_RNDIS_CONTROL,
};
#endif

#if defined(DEV_CONFIG_CDC) || defined(CONFIG_USB_ETH_RNDIS)

/* "Header Functional Descriptor" from CDC spec  5.2.3.1 */
struct header_desc {
	u8	bLength;
	u8	bDescriptorType;
	u8	bDescriptorSubType;

	u16	bcdCDC;
} __attribute__ ((packed));

static const struct header_desc header_desc = {
	.bLength =		sizeof header_desc,
	.bDescriptorType =	USB_DT_CS_INTERFACE,
	.bDescriptorSubType =	0,

	.bcdCDC =		__constant_cpu_to_le16 (0x0110),
};

/* "Union Functional Descriptor" from CDC spec 5.2.3.8 */
struct union_desc {
	u8	bLength;
	u8	bDescriptorType;
	u8	bDescriptorSubType;

	u8	bMasterInterface0;
	u8	bSlaveInterface0;