ether.c

linux下面gadget设备驱动

	/* 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.  Unfortunately MSFT's RNDIS driver is buggy; it
 * may hang or oops.  Since bugfixes (or accurate specs, letting Linux
 * work around those bugs) are unlikely to ever come from MSFT, you may
 * wish to avoid using RNDIS.
 *
 * MCCI offers an alternative to RNDIS if you need to connect to Windows
 * but have hardware that can't support CDC Ethernet.   We add descriptors
 * to present the CDC Subset as a (nonconformant) CDC MDLM variant called
 * "SAFE".  That borrows from both CDC Ethernet and CDC MDLM.  You can
 * get those drivers from MCCI, or bundled with various products.
 */

#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 =	USB_CDC_SUBCLASS_ETHERNET,
	.bInterfaceProtocol =	USB_CDC_PROTO_NONE,
	.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 =   USB_CDC_SUBCLASS_ACM,
	.bInterfaceProtocol =   USB_CDC_ACM_PROTO_VENDOR,
	.iInterface =           STRING_RNDIS_CONTROL,
};
#endif

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

	.bcdCDC =		__constant_cpu_to_le16 (0x0110),
};

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

static const struct usb_cdc_union_desc union_desc = {
	.bLength =		sizeof union_desc,
	.bDescriptorType =	USB_DT_CS_INTERFACE,
	.bDescriptorSubType =	USB_CDC_UNION_TYPE,

	.bMasterInterface0 =	0,	/* index of control interface */
	.bSlaveInterface0 =	1,	/* index of DATA interface */
};

#endif	/* CDC || RNDIS */

#ifdef	CONFIG_USB_ETH_RNDIS

static const struct usb_cdc_call_mgmt_descriptor call_mgmt_descriptor = {
	.bLength =		sizeof call_mgmt_descriptor,
	.bDescriptorType =	USB_DT_CS_INTERFACE,
	.bDescriptorSubType =	USB_CDC_CALL_MANAGEMENT_TYPE,

	.bmCapabilities =	0x00,
	.bDataInterface =	0x01,
};

static const struct usb_cdc_acm_descriptor acm_descriptor = {
	.bLength =		sizeof acm_descriptor,
	.bDescriptorType =	USB_DT_CS_INTERFACE,
	.bDescriptorSubType =	USB_CDC_ACM_TYPE,

	.bmCapabilities =	0x00,
};

#endif

#ifndef DEV_CONFIG_CDC

/* "SAFE" loosely follows CDC WMC MDLM, violating the spec in various
 * ways:  data endpoints live in the control interface, there's no data
 * interface, and it's not used to talk to a cell phone radio.
 */

static const struct usb_cdc_mdlm_desc mdlm_desc = {
	.bLength =		sizeof mdlm_desc,
	.bDescriptorType =	USB_DT_CS_INTERFACE,
	.bDescriptorSubType =	USB_CDC_MDLM_TYPE,

	.bcdVersion =		__constant_cpu_to_le16(0x0100),
	.bGUID = {
		0x5d, 0x34, 0xcf, 0x66, 0x11, 0x18, 0x11, 0xd6,
		0xa2, 0x1a, 0x00, 0x01, 0x02, 0xca, 0x9a, 0x7f,
	},
};

/* since "usb_cdc_mdlm_detail_desc" is a variable length structure, we
 * can't really use its struct.  All we do here is say that we're using
 * the submode of "SAFE" which directly matches the CDC Subset.
 */
static const u8 mdlm_detail_desc[] = {
	6,
	USB_DT_CS_INTERFACE,
	USB_CDC_MDLM_DETAIL_TYPE,

	0,	/* "SAFE" */
	0,	/* network control capabilities (none) */
	0,	/* network data capabilities ("raw" encapsulation) */
};

#endif

static const struct usb_cdc_ether_desc ether_desc = {
	.bLength =		sizeof ether_desc,
	.bDescriptorType =	USB_DT_CS_INTERFACE,
	.bDescriptorSubType =	USB_CDC_ETHERNET_TYPE,

	/* this descriptor actually adds value, surprise! */
	.iMACAddress =		STRING_ETHADDR,
	.bmEthernetStatistics =	__constant_cpu_to_le32 (0), /* no statistics */
	.wMaxSegmentSize =	__constant_cpu_to_le16 (ETH_FRAME_LEN),
	.wNumberMCFilters =	__constant_cpu_to_le16 (0),
	.bNumberPowerFilters =	0,
};


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

/* include the status endpoint if we can, even where it's optional.
 * use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
 * packet, to simplify cancellation; and a big transfer interval, to
 * waste less bandwidth.
 *
 * some drivers (like Linux 2.4 cdc-ether!) "need" it to exist even
 * if they ignore the connect/disconnect notifications that real aether
 * can provide.  more advanced cdc configurations might want to support
 * encapsulated commands (vendor-specific, using control-OUT).
 *
 * RNDIS requires the status endpoint, since it uses that encapsulation
 * mechanism for its funky RPC scheme.
 */

#define LOG2_STATUS_INTERVAL_MSEC	5	/* 1 << 5 == 32 msec */
#define STATUS_BYTECOUNT		16	/* 8 byte header + data */

static struct usb_endpoint_descriptor
fs_status_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bEndpointAddress =	USB_DIR_IN,
	.bmAttributes =		USB_ENDPOINT_XFER_INT,
	.wMaxPacketSize =	__constant_cpu_to_le16 (STATUS_BYTECOUNT),
	.bInterval =		1 << LOG2_STATUS_INTERVAL_MSEC,
};
#endif

#ifdef	DEV_CONFIG_CDC

/* the default data interface has no endpoints ... */

static const struct usb_interface_descriptor
data_nop_intf = {
	.bLength =		sizeof data_nop_intf,
	.bDescriptorType =	USB_DT_INTERFACE,

	.bInterfaceNumber =	1,
	.bAlternateSetting =	0,
	.bNumEndpoints =	0,
	.bInterfaceClass =	USB_CLASS_CDC_DATA,
	.bInterfaceSubClass =	0,
	.bInterfaceProtocol =	0,
};

/* ... but the "real" data interface has two bulk endpoints */

static const struct usb_interface_descriptor
data_intf = {
	.bLength =		sizeof data_intf,
	.bDescriptorType =	USB_DT_INTERFACE,

	.bInterfaceNumber =	1,
	.bAlternateSetting =	1,
	.bNumEndpoints =	2,
	.bInterfaceClass =	USB_CLASS_CDC_DATA,
	.bInterfaceSubClass =	0,
	.bInterfaceProtocol =	0,
	.iInterface =		STRING_DATA,
};

#endif

#ifdef	CONFIG_USB_ETH_RNDIS

/* RNDIS doesn't activate by changing to the "real" altsetting */

static const struct usb_interface_descriptor
rndis_data_intf = {
	.bLength =		sizeof rndis_data_intf,
	.bDescriptorType =	USB_DT_INTERFACE,

	.bInterfaceNumber =	1,
	.bAlternateSetting =	0,
	.bNumEndpoints =	2,
	.bInterfaceClass =	USB_CLASS_CDC_DATA,
	.bInterfaceSubClass =	0,
	.bInterfaceProtocol =	0,
	.iInterface =		STRING_DATA,
};

#endif

#ifdef DEV_CONFIG_SUBSET

/*
 * "Simple" CDC-subset option is a simple vendor-neutral model that most
 * full speed controllers can handle:  one interface, two bulk endpoints.
 *
 * To assist host side drivers, we fancy it up a bit, and add descriptors
 * so some host side drivers will understand it as a "SAFE" variant.
 */

static const struct usb_interface_descriptor
subset_data_intf = {
	.bLength =		sizeof subset_data_intf,
	.bDescriptorType =	USB_DT_INTERFACE,

	.bInterfaceNumber =	0,
	.bAlternateSetting =	0,
	.bNumEndpoints =	2,
	.bInterfaceClass =      USB_CLASS_COMM,
	.bInterfaceSubClass =	USB_CDC_SUBCLASS_MDLM,
	.bInterfaceProtocol =	0,
	.iInterface =		STRING_DATA,
};

#endif	/* SUBSET */


static struct usb_endpoint_descriptor
fs_source_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bEndpointAddress =	USB_DIR_IN,
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
};

static struct usb_endpoint_descriptor
fs_sink_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bEndpointAddress =	USB_DIR_OUT,
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
};

static const struct usb_descriptor_header *fs_eth_function [11] = {
	(struct usb_descriptor_header *) &otg_descriptor,
#ifdef DEV_CONFIG_CDC
	/* "cdc" mode descriptors */
	(struct usb_descriptor_header *) &control_intf,
	(struct usb_descriptor_header *) &header_desc,
	(struct usb_descriptor_header *) &union_desc,
	(struct usb_descriptor_header *) &ether_desc,
	/* NOTE: status endpoint may need to be removed */
	(struct usb_descriptor_header *) &fs_status_desc,
	/* data interface, with altsetting */
	(struct usb_descriptor_header *) &data_nop_intf,
	(struct usb_descriptor_header *) &data_intf,
	(struct usb_descriptor_header *) &fs_source_desc,
	(struct usb_descriptor_header *) &fs_sink_desc,
	NULL,
#endif /* DEV_CONFIG_CDC */
};

static inline void __init fs_subset_descriptors(void)
{
#ifdef DEV_CONFIG_SUBSET
	/* behavior is "CDC Subset"; extra descriptors say "SAFE" */
	fs_eth_function[1] = (struct usb_descriptor_header *) &subset_data_intf;
	fs_eth_function[2] = (struct usb_descriptor_header *) &header_desc;
	fs_eth_function[3] = (struct usb_descriptor_header *) &mdlm_desc;
	fs_eth_function[4] = (struct usb_descriptor_header *) &mdlm_detail_desc;
	fs_eth_function[5] = (struct usb_descriptor_header *) &ether_desc;
	fs_eth_function[6] = (struct usb_descriptor_header *) &fs_source_desc;
	fs_eth_function[7] = (struct usb_descriptor_header *) &fs_sink_desc;
	fs_eth_function[8] = NULL;
#else
	fs_eth_function[1] = NULL;
#endif
}

#ifdef	CONFIG_USB_ETH_RNDIS
static const struct usb_descriptor_header *fs_rndis_function [] = {
	(struct usb_descriptor_header *) &otg_descriptor,
	/* control interface matches ACM, not Ethernet */
	(struct usb_descriptor_header *) &rndis_control_intf,
	(struct usb_descriptor_header *) &header_desc,
	(struct usb_descriptor_header *) &call_mgmt_descriptor,
	(struct usb_descriptor_header *) &acm_descriptor,
	(struct usb_descriptor_header *) &union_desc,
	(struct usb_descriptor_header *) &fs_status_desc,
	/* data interface has no altsetting */
	(struct usb_descriptor_header *) &rndis_data_intf,
	(struct usb_descriptor_header *) &fs_source_desc,
	(struct usb_descriptor_header *) &fs_sink_desc,
	NULL,
};
#endif

/*
 * usb 2.0 devices need to expose both high speed and full speed
 * descriptors, unless they only run at full speed.
 */

#if defined(DEV_CONFIG_CDC) || defined(CONFIG_USB_ETH_RNDIS)
static struct usb_endpoint_descriptor
hs_status_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bmAttributes =		USB_ENDPOINT_XFER_INT,
	.wMaxPacketSize =	__constant_cpu_to_le16 (STATUS_BYTECOUNT),
	.bInterval =		LOG2_STATUS_INTERVAL_MSEC + 4,
};
#endif /* DEV_CONFIG_CDC */

static struct usb_endpoint_descriptor
hs_source_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize =	__constant_cpu_to_le16 (512),
};

static struct usb_endpoint_descriptor
hs_sink_desc = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,

	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize =	__constant_cpu_to_le16 (512),
};

static struct usb_qualifier_descriptor
dev_qualifier = {
	.bLength =		sizeof dev_qualifier,
	.bDescriptorType =	USB_DT_DEVICE_QUALIFIER,

	.bcdUSB =		__constant_cpu_to_le16 (0x0200),
	.bDeviceClass =		USB_CLASS_COMM,

	.bNumConfigurations =	1,
};

static const struct usb_descriptor_header *hs_eth_function [11] = {
	(struct usb_descriptor_header *) &otg_descriptor,
#ifdef DEV_CONFIG_CDC
	/* "cdc" mode descriptors */
	(struct usb_descriptor_header *) &control_intf,
	(struct usb_descriptor_header *) &header_desc,
	(struct usb_descriptor_header *) &union_desc,
	(struct usb_descriptor_header *) &ether_desc,
	/* NOTE: status endpoint may need to be removed */
	(struct usb_descriptor_header *) &hs_status_desc,
	/* data interface, with altsetting */
	(struct usb_descriptor_header *) &data_nop_intf,
	(struct usb_descriptor_header *) &data_intf,
	(struct usb_descriptor_header *) &hs_source_desc,
	(struct usb_descriptor_header *) &hs_sink_desc,
	NULL,
#endif /* DEV_CONFIG_CDC */
};

static inline void __init hs_subset_descriptors(void)
{
#ifdef DEV_CONFIG_SUBSET
	/* behavior is "CDC Subset"; extra descriptors say "SAFE" */
	hs_eth_function[1] = (struct usb_descriptor_header *) &subset_data_intf;
	hs_eth_function[2] = (struct usb_descriptor_header *) &header_desc;
	hs_eth_function[3] = (struct usb_descriptor_header *) &mdlm_desc;
	hs_eth_function[4] = (struct usb_descriptor_header *) &mdlm_detail_desc;
	hs_eth_function[5] = (struct usb_descriptor_header *) &ether_desc;
	hs_eth_function[6] = (struct usb_descriptor_header *) &hs_source_desc;
	hs_eth_function[7] = (struct usb_descriptor_header *) &hs_sink_desc;
	hs_eth_function[8] = NULL;
#else
	hs_eth_function[1] = NULL;
#endif
}

#ifdef	CONFIG_USB_ETH_RNDIS
static const struct usb_descriptor_header *hs_rndis_function [] = {
	(struct usb_descriptor_header *) &otg_descriptor,
	/* control interface matches ACM, not Ethernet */
	(struct usb_descriptor_header *) &rndis_control_intf,
	(struct usb_descriptor_header *) &header_desc,
	(struct usb_descriptor_header *) &call_mgmt_descriptor,
	(struct usb_descriptor_header *) &acm_descriptor,
	(struct usb_descriptor_header *) &union_desc,
	(struct usb_descriptor_header *) &hs_status_desc,
	/* data interface has no altsetting */
	(struct usb_descriptor_header *) &rndis_data_intf,
	(struct usb_descriptor_header *) &hs_source_desc,
	(struct usb_descriptor_header *) &hs_sink_desc,
	NULL,
};
#endif


/* maxpacket and other transfer characteristics vary by speed. */
static inline struct usb_endpoint_descriptor *
ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *hs,
		struct usb_endpoint_descriptor *fs)
{
	if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
		return hs;
	return fs;
}


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

/* descriptors that are built on-demand */

static char				manufacturer [50];
static char				product_desc [40] = DRIVER_DESC;
static char				serial_number [20];

/* address that the host will use ... usually assigned at random */
static char				ethaddr [2 * ETH_ALEN + 1];

/* static strings, in UTF-8 */
static struct usb_string		strings [] = {
	{ STRING_MANUFACTURER,	manufacturer, },
	{ STRING_PRODUCT,	product_desc, },
	{ STRING_SERIALNUMBER,	serial_number, },
	{ STRING_DATA,		"Ethernet Data", },
	{ STRING_ETHADDR,	ethaddr, },
#ifdef	DEV_CONFIG_CDC
	{ STRING_CDC,		"CDC Ethernet", },
	{ STRING_CONTROL,	"CDC Communications Control", },
#endif
#ifdef	DEV_CONFIG_SUBSET
	{ STRING_SUBSET,	"CDC Ethernet Subset", },
#endif
#ifdef	CONFIG_USB_ETH_RNDIS