file_storage.c

LINUX2.4.18内核下的usb GADGET驱动程序

	.bEndpointAddress =	USB_DIR_IN,
	.bmAttributes =		USB_ENDPOINT_XFER_INT,
	.wMaxPacketSize =	__constant_cpu_to_le16(2),
	.bInterval =		32,	// frames -> 32 ms
};

static const struct usb_descriptor_header *fs_function[] = {
	(struct usb_descriptor_header *) &intf_desc,
	(struct usb_descriptor_header *) &fs_bulk_in_desc,
	(struct usb_descriptor_header *) &fs_bulk_out_desc,
	(struct usb_descriptor_header *) &fs_intr_in_desc,
	NULL,
};


#ifdef	CONFIG_USB_GADGET_DUALSPEED

/*
 * USB 2.0 devices need to expose both high speed and full speed
 * descriptors, unless they only run at full speed.
 *
 * That means alternate endpoint descriptors (bigger packets)
 * and a "device qualifier" ... plus more construction options
 * for the config descriptor.
 */
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_PER_INTERFACE,

	.bNumConfigurations =	1,
};

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

	/* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize =	__constant_cpu_to_le16(512),
};

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

	/* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize =	__constant_cpu_to_le16(512),
	.bInterval =		1,	// NAK every 1 uframe
};

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

	/* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
	.bmAttributes =		USB_ENDPOINT_XFER_INT,
	.wMaxPacketSize =	__constant_cpu_to_le16(2),
	.bInterval =		9,	// 2**(9-1) = 256 uframes -> 32 ms
};

static const struct usb_descriptor_header *hs_function[] = {
	(struct usb_descriptor_header *) &intf_desc,
	(struct usb_descriptor_header *) &hs_bulk_in_desc,
	(struct usb_descriptor_header *) &hs_bulk_out_desc,
	(struct usb_descriptor_header *) &hs_intr_in_desc,
	NULL,
};

/* Maxpacket and other transfer characteristics vary by speed. */
#define ep_desc(g,fs,hs)	(((g)->speed==USB_SPEED_HIGH) ? (hs) : (fs))

#else

/* If there's no high speed support, always use the full-speed descriptor. */
#define ep_desc(g,fs,hs)	fs

#endif	/* !CONFIG_USB_GADGET_DUALSPEED */


/* The CBI specification limits the serial string to 12 uppercase hexadecimal
 * characters. */
static char				manufacturer[40];
static char				serial[13];

/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
static struct usb_string		strings[] = {
	{STRING_MANUFACTURER,	manufacturer},
	{STRING_PRODUCT,	longname},
	{STRING_SERIAL,		serial},
	{}
};

static struct usb_gadget_strings	stringtab = {
	.language	= 0x0409,		// en-us
	.strings	= strings,
};


/*
 * Config descriptors must agree with the code that sets configurations
 * and with code managing interfaces and their altsettings.  They must
 * also handle different speeds and other-speed requests.
 */
static int populate_config_buf(enum usb_device_speed speed,
		u8 *buf, u8 type, unsigned index)
{
	int					len;
	const struct usb_descriptor_header	**function;

	if (index > 0)
		return -EINVAL;

#ifdef CONFIG_USB_GADGET_DUALSPEED
	if (type == USB_DT_OTHER_SPEED_CONFIG)
		speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed;
	if (speed == USB_SPEED_HIGH)
		function = hs_function;
	else
#endif
		function = fs_function;

	len = usb_gadget_config_buf(&config_desc, buf, EP0_BUFSIZE, function);
	if (len < 0)
		return len;
	((struct usb_config_descriptor *) buf)->bDescriptorType = type;
	return len;
}


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

/* These routines may be called in process context or in_irq */

static void wakeup_thread(struct fsg_dev *fsg)
{
	/* Tell the main thread that something has happened */
	fsg->thread_wakeup_needed = 1;
	wake_up_all(&fsg->thread_wqh);
}


static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state)
{
	unsigned long		flags;
	struct task_struct	*thread_task;

	/* Do nothing if a higher-priority exception is already in progress.
	 * If a lower-or-equal priority exception is in progress, preempt it
	 * and notify the main thread by sending it a signal. */
	spin_lock_irqsave(&fsg->lock, flags);
	if (fsg->state <= new_state) {
		fsg->exception_req_tag = fsg->ep0_req_tag;
		fsg->state = new_state;
		thread_task = fsg->thread_task;
		if (thread_task)
			send_sig_info(SIGUSR1, (void *) 1L, thread_task);
	}
	spin_unlock_irqrestore(&fsg->lock, flags);
}


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

/* The disconnect callback and ep0 routines.  These always run in_irq,
 * except that ep0_queue() is called in the main thread to acknowledge
 * completion of various requests: set config, set interface, and
 * Bulk-only device reset. */

static void fsg_disconnect(struct usb_gadget *gadget)
{
	struct fsg_dev		*fsg = get_gadget_data(gadget);

	DBG(fsg, "disconnect or port reset\n");
	raise_exception(fsg, FSG_STATE_DISCONNECT);
}


static int ep0_queue(struct fsg_dev *fsg)
{
	int	rc;

	rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC);
	if (rc != 0 && rc != -ESHUTDOWN) {

		/* We can't do much more than wait for a reset */
		WARN(fsg, "error in submission: %s --> %d\n",
				fsg->ep0->name, rc);
	}
	return rc;
}

static void ep0_complete(struct usb_ep *ep, struct usb_request *req)
{
	struct fsg_dev		*fsg = (struct fsg_dev *) ep->driver_data;

	if (req->actual > 0)
		dump_msg(fsg, fsg->ep0req_name, req->buf, req->actual);
	if (req->status || req->actual != req->length)
		DBG(fsg, "%s --> %d, %u/%u\n", __FUNCTION__,
				req->status, req->actual, req->length);
	if (req->status == -ECONNRESET)		// Request was cancelled
		usb_ep_fifo_flush(ep);

	if (req->status == 0 && req->context)
		((fsg_routine_t) (req->context))(fsg);
}


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

/* Bulk and interrupt endpoint completion handlers.
 * These always run in_irq. */

static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
{
	struct fsg_dev		*fsg = (struct fsg_dev *) ep->driver_data;
	struct fsg_buffhd	*bh = (struct fsg_buffhd *) req->context;

	if (req->status || req->actual != req->length)
		DBG(fsg, "%s --> %d, %u/%u\n", __FUNCTION__,
				req->status, req->actual, req->length);
	if (req->status == -ECONNRESET)		// Request was cancelled
		usb_ep_fifo_flush(ep);

	/* Hold the lock while we update the request and buffer states */
	spin_lock(&fsg->lock);
	bh->inreq_busy = 0;
	bh->state = BUF_STATE_EMPTY;
	spin_unlock(&fsg->lock);
	wakeup_thread(fsg);
}

static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
{
	struct fsg_dev		*fsg = (struct fsg_dev *) ep->driver_data;
	struct fsg_buffhd	*bh = (struct fsg_buffhd *) req->context;

	dump_msg(fsg, "bulk-out", req->buf, req->actual);
	if (req->status || req->actual != bh->bulk_out_intended_length)
		DBG(fsg, "%s --> %d, %u/%u\n", __FUNCTION__,
				req->status, req->actual,
				bh->bulk_out_intended_length);
	if (req->status == -ECONNRESET)		// Request was cancelled
		usb_ep_fifo_flush(ep);

	/* Hold the lock while we update the request and buffer states */
	spin_lock(&fsg->lock);
	bh->outreq_busy = 0;
	bh->state = BUF_STATE_FULL;
	spin_unlock(&fsg->lock);
	wakeup_thread(fsg);
}

static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
{
#ifdef CONFIG_USB_FILE_STORAGE_TEST
	struct fsg_dev		*fsg = (struct fsg_dev *) ep->driver_data;
	struct fsg_buffhd	*bh = (struct fsg_buffhd *) req->context;

	if (req->status || req->actual != req->length)
		DBG(fsg, "%s --> %d, %u/%u\n", __FUNCTION__,
				req->status, req->actual, req->length);
	if (req->status == -ECONNRESET)		// Request was cancelled
		usb_ep_fifo_flush(ep);

	/* Hold the lock while we update the request and buffer states */
	spin_lock(&fsg->lock);
	fsg->intreq_busy = 0;
	bh->state = BUF_STATE_EMPTY;
	spin_unlock(&fsg->lock);
	wakeup_thread(fsg);
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
}


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

/* Ep0 class-specific handlers.  These always run in_irq. */

static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
{
#ifdef CONFIG_USB_FILE_STORAGE_TEST
	struct usb_request	*req = fsg->ep0req;
	static u8		cbi_reset_cmnd[6] = {
			SC_SEND_DIAGNOSTIC, 4, 0xff, 0xff, 0xff, 0xff};

	/* Error in command transfer? */
	if (req->status || req->length != req->actual ||
			req->actual < 6 || req->actual > MAX_COMMAND_SIZE) {

		/* Not all controllers allow a protocol stall after
		 * receiving control-out data, but we'll try anyway. */
		fsg_set_halt(fsg, fsg->ep0);
		return;			// Wait for reset
	}

	/* Is it the special reset command? */
	if (req->actual >= sizeof cbi_reset_cmnd &&
			memcmp(req->buf, cbi_reset_cmnd,
				sizeof cbi_reset_cmnd) == 0) {

		/* Raise an exception to stop the current operation
		 * and reinitialize our state. */
		DBG(fsg, "cbi reset request\n");
		raise_exception(fsg, FSG_STATE_RESET);
		return;
	}

	VDBG(fsg, "CB[I] accept device-specific command\n");
	spin_lock(&fsg->lock);

	/* Save the command for later */
	if (fsg->cbbuf_cmnd_size)
		WARN(fsg, "CB[I] overwriting previous command\n");
	fsg->cbbuf_cmnd_size = req->actual;
	memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size);

	spin_unlock(&fsg->lock);
	wakeup_thread(fsg);
#endif /* CONFIG_USB_FILE_STORAGE_TEST */
}


static int class_setup_req(struct fsg_dev *fsg,
		const struct usb_ctrlrequest *ctrl)
{
	struct usb_request	*req = fsg->ep0req;
	int			value = -EOPNOTSUPP;

	if (!fsg->config)
		return value;

	/* Handle Bulk-only class-specific requests */
	if (transport_is_bbb()) {
		switch (ctrl->bRequest) {

		case USB_BULK_RESET_REQUEST:
			if (ctrl->bRequestType != (USB_DIR_OUT |
					USB_TYPE_CLASS | USB_RECIP_INTERFACE))
				break;
			if (ctrl->wIndex != 0) {
				value = -EDOM;
				break;
			}

			/* Raise an exception to stop the current operation
			 * and reinitialize our state. */
			DBG(fsg, "bulk reset request\n");
			raise_exception(fsg, FSG_STATE_RESET);
			value = DELAYED_STATUS;
			break;

		case USB_BULK_GET_MAX_LUN_REQUEST:
			if (ctrl->bRequestType != (USB_DIR_IN |
					USB_TYPE_CLASS | USB_RECIP_INTERFACE))
				break;
			if (ctrl->wIndex != 0) {
				value = -EDOM;
				break;
			}
			VDBG(fsg, "get max LUN\n");
			*(u8 *) req->buf = fsg->nluns - 1;
			value = min(ctrl->wLength, (u16) 1);
			break;
		}
	}

	/* Handle CBI class-specific requests */
	else {
		switch (ctrl->bRequest) {

		case USB_CBI_ADSC_REQUEST:
			if (ctrl->bRequestType != (USB_DIR_OUT |
					USB_TYPE_CLASS | USB_RECIP_INTERFACE))
				break;
			if (ctrl->wIndex != 0) {
				value = -EDOM;
				break;
			}
			if (ctrl->wLength > MAX_COMMAND_SIZE) {
				value = -EOVERFLOW;
				break;
			}
			value = ctrl->wLength;
			fsg->ep0req->context = received_cbi_adsc;
			break;
		}
	}

	if (value == -EOPNOTSUPP)
		VDBG(fsg,
			"unknown class-specific control req "
			"%02x.%02x v%04x i%04x l%u\n",
			ctrl->bRequestType, ctrl->bRequest,
			ctrl->wValue, ctrl->wIndex, ctrl->wLength);
	return value;
}


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

/* Ep0 standard request handlers.  These always run in_irq. */

static int standard_setup_req(struct fsg_dev *fsg,
		const struct usb_ctrlrequest *ctrl)
{
	struct usb_request	*req = fsg->ep0req;
	int			value = -EOPNOTSUPP;

	/* Usually this just stores reply data in the pre-allocated ep0 buffer,
	 * but config change events will also reconfigure hardware. */
	switch (ctrl->bRequest) {

	case USB_REQ_GET_DESCRIPTOR:
		if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
				USB_RECIP_DEVICE))
			break;
		switch (ctrl->wValue >> 8) {

		case USB_DT_DEVICE:
			VDBG(fsg, "get device descriptor\n");
			value = min(ctrl->wLength, (u16) sizeof device_desc);
			memcpy(req->buf, &device_desc, value);
			break;
#ifdef CONFIG_USB_GADGET_DUALSPEED
		case USB_DT_DEVICE_QUALIFIER:
			VDBG(fsg, "get device qualifier\n");
			if (!fsg->gadget->is_dualspeed)
				break;
			value = min(ctrl->wLength, (u16) sizeof dev_qualifier);
			memcpy(req->buf, &dev_qualifier, value);
			break;

		case USB_DT_OTHER_SPEED_CONFIG:
			VDBG(fsg, "get other-speed config descriptor\n");
			if (!fsg->gadget->is_dualspeed)
				break;
			goto get_config;
#endif
		case USB_DT_CONFIG:
			VDBG(fsg, "get configuration descriptor\n");
#ifdef CONFIG_USB_GADGET_DUALSPEED
		get_config: