usb: gadget: Gadget directory cleanup - group usb functions

The drivers/usb/gadget directory contains many files.
Files which are related can be distributed into separate directories.
This patch moves the USB functions implementations into a separate directory.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 1247 insertions, 0 deletions

diff --git a/drivers/usb/gadget/function/f_sourcesink.c b/drivers/usb/gadget/function/f_sourcesink.c
new file mode 100644
index 000000000000..d3cd52db78fe
--- /dev/null
+++ b/drivers/usb/gadget/function/f_sourcesink.c
@@ -0,0 +1,1247 @@
+/*
+ * f_sourcesink.c - USB peripheral source/sink configuration driver
+ *
+ * Copyright (C) 2003-2008 David Brownell
+ * Copyright (C) 2008 by 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/slab.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/usb/composite.h>
+#include <linux/err.h>
+
+#include "g_zero.h"
+#include "gadget_chips.h"
+#include "u_f.h"
+
+/*
+ * SOURCE/SINK FUNCTION ... a primary testing vehicle for USB peripheral
+ * controller drivers.
+ *
+ * This just sinks bulk packets OUT to the peripheral and sources them IN
+ * to the host, optionally with specific data patterns for integrity tests.
+ * As such it supports basic functionality and load tests.
+ *
+ * In terms of control messaging, this supports all the standard requests
+ * plus two that support control-OUT tests.  If the optional "autoresume"
+ * mode is enabled, it provides good functional coverage for the "USBCV"
+ * test harness from USB-IF.
+ *
+ * Note that because this doesn't queue more than one request at a time,
+ * some other function must be used to test queueing logic.  The network
+ * link (g_ether) is the best overall option for that, since its TX and RX
+ * queues are relatively independent, will receive a range of packet sizes,
+ * and can often be made to run out completely.  Those issues are important
+ * when stress testing peripheral controller drivers.
+ *
+ *
+ * This is currently packaged as a configuration driver, which can't be
+ * combined with other functions to make composite devices.  However, it
+ * can be combined with other independent configurations.
+ */
+struct f_sourcesink {
+	struct usb_function	function;
+
+	struct usb_ep		*in_ep;
+	struct usb_ep		*out_ep;
+	struct usb_ep		*iso_in_ep;
+	struct usb_ep		*iso_out_ep;
+	int			cur_alt;
+};
+
+static inline struct f_sourcesink *func_to_ss(struct usb_function *f)
+{
+	return container_of(f, struct f_sourcesink, function);
+}
+
+static unsigned pattern;
+static unsigned isoc_interval;
+static unsigned isoc_maxpacket;
+static unsigned isoc_mult;
+static unsigned isoc_maxburst;
+static unsigned buflen;
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_interface_descriptor source_sink_intf_alt0 = {
+	.bLength =		USB_DT_INTERFACE_SIZE,
+	.bDescriptorType =	USB_DT_INTERFACE,
+
+	.bAlternateSetting =	0,
+	.bNumEndpoints =	2,
+	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
+	/* .iInterface		= DYNAMIC */
+};
+
+static struct usb_interface_descriptor source_sink_intf_alt1 = {
+	.bLength =		USB_DT_INTERFACE_SIZE,
+	.bDescriptorType =	USB_DT_INTERFACE,
+
+	.bAlternateSetting =	1,
+	.bNumEndpoints =	4,
+	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
+	/* .iInterface		= DYNAMIC */
+};
+
+/* full speed support: */
+
+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 struct usb_endpoint_descriptor fs_iso_source_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bEndpointAddress =	USB_DIR_IN,
+	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize =	cpu_to_le16(1023),
+	.bInterval =		4,
+};
+
+static struct usb_endpoint_descriptor fs_iso_sink_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bEndpointAddress =	USB_DIR_OUT,
+	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize =	cpu_to_le16(1023),
+	.bInterval =		4,
+};
+
+static struct usb_descriptor_header *fs_source_sink_descs[] = {
+	(struct usb_descriptor_header *) &source_sink_intf_alt0,
+	(struct usb_descriptor_header *) &fs_sink_desc,
+	(struct usb_descriptor_header *) &fs_source_desc,
+	(struct usb_descriptor_header *) &source_sink_intf_alt1,
+#define FS_ALT_IFC_1_OFFSET	3
+	(struct usb_descriptor_header *) &fs_sink_desc,
+	(struct usb_descriptor_header *) &fs_source_desc,
+	(struct usb_descriptor_header *) &fs_iso_sink_desc,
+	(struct usb_descriptor_header *) &fs_iso_source_desc,
+	NULL,
+};
+
+/* high speed support: */
+
+static struct usb_endpoint_descriptor hs_source_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	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 =	cpu_to_le16(512),
+};
+
+static struct usb_endpoint_descriptor hs_iso_source_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize =	cpu_to_le16(1024),
+	.bInterval =		4,
+};
+
+static struct usb_endpoint_descriptor hs_iso_sink_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize =	cpu_to_le16(1024),
+	.bInterval =		4,
+};
+
+static struct usb_descriptor_header *hs_source_sink_descs[] = {
+	(struct usb_descriptor_header *) &source_sink_intf_alt0,
+	(struct usb_descriptor_header *) &hs_source_desc,
+	(struct usb_descriptor_header *) &hs_sink_desc,
+	(struct usb_descriptor_header *) &source_sink_intf_alt1,
+#define HS_ALT_IFC_1_OFFSET	3
+	(struct usb_descriptor_header *) &hs_source_desc,
+	(struct usb_descriptor_header *) &hs_sink_desc,
+	(struct usb_descriptor_header *) &hs_iso_source_desc,
+	(struct usb_descriptor_header *) &hs_iso_sink_desc,
+	NULL,
+};
+
+/* super speed support: */
+
+static struct usb_endpoint_descriptor ss_source_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	cpu_to_le16(1024),
+};
+
+static struct usb_ss_ep_comp_descriptor ss_source_comp_desc = {
+	.bLength =		USB_DT_SS_EP_COMP_SIZE,
+	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
+
+	.bMaxBurst =		0,
+	.bmAttributes =		0,
+	.wBytesPerInterval =	0,
+};
+
+static struct usb_endpoint_descriptor ss_sink_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	cpu_to_le16(1024),
+};
+
+static struct usb_ss_ep_comp_descriptor ss_sink_comp_desc = {
+	.bLength =		USB_DT_SS_EP_COMP_SIZE,
+	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
+
+	.bMaxBurst =		0,
+	.bmAttributes =		0,
+	.wBytesPerInterval =	0,
+};
+
+static struct usb_endpoint_descriptor ss_iso_source_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize =	cpu_to_le16(1024),
+	.bInterval =		4,
+};
+
+static struct usb_ss_ep_comp_descriptor ss_iso_source_comp_desc = {
+	.bLength =		USB_DT_SS_EP_COMP_SIZE,
+	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
+
+	.bMaxBurst =		0,
+	.bmAttributes =		0,
+	.wBytesPerInterval =	cpu_to_le16(1024),
+};
+
+static struct usb_endpoint_descriptor ss_iso_sink_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_ISOC,
+	.wMaxPacketSize =	cpu_to_le16(1024),
+	.bInterval =		4,
+};
+
+static struct usb_ss_ep_comp_descriptor ss_iso_sink_comp_desc = {
+	.bLength =		USB_DT_SS_EP_COMP_SIZE,
+	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
+
+	.bMaxBurst =		0,
+	.bmAttributes =		0,
+	.wBytesPerInterval =	cpu_to_le16(1024),
+};
+
+static struct usb_descriptor_header *ss_source_sink_descs[] = {
+	(struct usb_descriptor_header *) &source_sink_intf_alt0,
+	(struct usb_descriptor_header *) &ss_source_desc,
+	(struct usb_descriptor_header *) &ss_source_comp_desc,
+	(struct usb_descriptor_header *) &ss_sink_desc,
+	(struct usb_descriptor_header *) &ss_sink_comp_desc,
+	(struct usb_descriptor_header *) &source_sink_intf_alt1,
+#define SS_ALT_IFC_1_OFFSET	5
+	(struct usb_descriptor_header *) &ss_source_desc,
+	(struct usb_descriptor_header *) &ss_source_comp_desc,
+	(struct usb_descriptor_header *) &ss_sink_desc,
+	(struct usb_descriptor_header *) &ss_sink_comp_desc,
+	(struct usb_descriptor_header *) &ss_iso_source_desc,
+	(struct usb_descriptor_header *) &ss_iso_source_comp_desc,
+	(struct usb_descriptor_header *) &ss_iso_sink_desc,
+	(struct usb_descriptor_header *) &ss_iso_sink_comp_desc,
+	NULL,
+};
+
+/* function-specific strings: */
+
+static struct usb_string strings_sourcesink[] = {
+	[0].s = "source and sink data",
+	{  }			/* end of list */
+};
+
+static struct usb_gadget_strings stringtab_sourcesink = {
+	.language	= 0x0409,	/* en-us */
+	.strings	= strings_sourcesink,
+};
+
+static struct usb_gadget_strings *sourcesink_strings[] = {
+	&stringtab_sourcesink,
+	NULL,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static inline struct usb_request *ss_alloc_ep_req(struct usb_ep *ep, int len)
+{
+	return alloc_ep_req(ep, len, buflen);
+}
+
+void free_ep_req(struct usb_ep *ep, struct usb_request *req)
+{
+	kfree(req->buf);
+	usb_ep_free_request(ep, req);
+}
+
+static void disable_ep(struct usb_composite_dev *cdev, struct usb_ep *ep)
+{
+	int			value;
+
+	if (ep->driver_data) {
+		value = usb_ep_disable(ep);
+		if (value < 0)
+			DBG(cdev, "disable %s --> %d\n",
+					ep->name, value);
+		ep->driver_data = NULL;
+	}
+}
+
+void disable_endpoints(struct usb_composite_dev *cdev,
+		struct usb_ep *in, struct usb_ep *out,
+		struct usb_ep *iso_in, struct usb_ep *iso_out)
+{
+	disable_ep(cdev, in);
+	disable_ep(cdev, out);
+	if (iso_in)
+		disable_ep(cdev, iso_in);
+	if (iso_out)
+		disable_ep(cdev, iso_out);
+}
+
+static int
+sourcesink_bind(struct usb_configuration *c, struct usb_function *f)
+{
+	struct usb_composite_dev *cdev = c->cdev;
+	struct f_sourcesink	*ss = func_to_ss(f);
+	int	id;
+	int ret;
+
+	/* allocate interface ID(s) */
+	id = usb_interface_id(c, f);
+	if (id < 0)
+		return id;
+	source_sink_intf_alt0.bInterfaceNumber = id;
+	source_sink_intf_alt1.bInterfaceNumber = id;
+
+	/* allocate bulk endpoints */
+	ss->in_ep = usb_ep_autoconfig(cdev->gadget, &fs_source_desc);
+	if (!ss->in_ep) {
+autoconf_fail:
+		ERROR(cdev, "%s: can't autoconfigure on %s\n",
+			f->name, cdev->gadget->name);
+		return -ENODEV;
+	}
+	ss->in_ep->driver_data = cdev;	/* claim */
+
+	ss->out_ep = usb_ep_autoconfig(cdev->gadget, &fs_sink_desc);
+	if (!ss->out_ep)
+		goto autoconf_fail;
+	ss->out_ep->driver_data = cdev;	/* claim */
+
+	/* sanity check the isoc module parameters */
+	if (isoc_interval < 1)
+		isoc_interval = 1;
+	if (isoc_interval > 16)
+		isoc_interval = 16;
+	if (isoc_mult > 2)
+		isoc_mult = 2;
+	if (isoc_maxburst > 15)
+		isoc_maxburst = 15;
+
+	/* fill in the FS isoc descriptors from the module parameters */
+	fs_iso_source_desc.wMaxPacketSize = isoc_maxpacket > 1023 ?
+						1023 : isoc_maxpacket;
+	fs_iso_source_desc.bInterval = isoc_interval;
+	fs_iso_sink_desc.wMaxPacketSize = isoc_maxpacket > 1023 ?
+						1023 : isoc_maxpacket;
+	fs_iso_sink_desc.bInterval = isoc_interval;
+
+	/* allocate iso endpoints */
+	ss->iso_in_ep = usb_ep_autoconfig(cdev->gadget, &fs_iso_source_desc);
+	if (!ss->iso_in_ep)
+		goto no_iso;
+	ss->iso_in_ep->driver_data = cdev;	/* claim */
+
+	ss->iso_out_ep = usb_ep_autoconfig(cdev->gadget, &fs_iso_sink_desc);
+	if (ss->iso_out_ep) {
+		ss->iso_out_ep->driver_data = cdev;	/* claim */
+	} else {
+		ss->iso_in_ep->driver_data = NULL;
+		ss->iso_in_ep = NULL;
+no_iso:
+		/*
+		 * We still want to work even if the UDC doesn't have isoc
+		 * endpoints, so null out the alt interface that contains
+		 * them and continue.
+		 */
+		fs_source_sink_descs[FS_ALT_IFC_1_OFFSET] = NULL;
+		hs_source_sink_descs[HS_ALT_IFC_1_OFFSET] = NULL;
+		ss_source_sink_descs[SS_ALT_IFC_1_OFFSET] = NULL;
+	}
+
+	if (isoc_maxpacket > 1024)
+		isoc_maxpacket = 1024;
+
+	/* support high speed hardware */
+	hs_source_desc.bEndpointAddress = fs_source_desc.bEndpointAddress;
+	hs_sink_desc.bEndpointAddress = fs_sink_desc.bEndpointAddress;
+
+	/*
+	 * Fill in the HS isoc descriptors from the module parameters.
+	 * We assume that the user knows what they are doing and won't
+	 * give parameters that their UDC doesn't support.
+	 */
+	hs_iso_source_desc.wMaxPacketSize = isoc_maxpacket;
+	hs_iso_source_desc.wMaxPacketSize |= isoc_mult << 11;
+	hs_iso_source_desc.bInterval = isoc_interval;
+	hs_iso_source_desc.bEndpointAddress =
+		fs_iso_source_desc.bEndpointAddress;
+
+	hs_iso_sink_desc.wMaxPacketSize = isoc_maxpacket;
+	hs_iso_sink_desc.wMaxPacketSize |= isoc_mult << 11;
+	hs_iso_sink_desc.bInterval = isoc_interval;
+	hs_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
+
+	/* support super speed hardware */
+	ss_source_desc.bEndpointAddress =
+		fs_source_desc.bEndpointAddress;
+	ss_sink_desc.bEndpointAddress =
+		fs_sink_desc.bEndpointAddress;
+
+	/*
+	 * Fill in the SS isoc descriptors from the module parameters.
+	 * We assume that the user knows what they are doing and won't
+	 * give parameters that their UDC doesn't support.
+	 */
+	ss_iso_source_desc.wMaxPacketSize = isoc_maxpacket;
+	ss_iso_source_desc.bInterval = isoc_interval;
+	ss_iso_source_comp_desc.bmAttributes = isoc_mult;
+	ss_iso_source_comp_desc.bMaxBurst = isoc_maxburst;
+	ss_iso_source_comp_desc.wBytesPerInterval =
+		isoc_maxpacket * (isoc_mult + 1) * (isoc_maxburst + 1);
+	ss_iso_source_desc.bEndpointAddress =
+		fs_iso_source_desc.bEndpointAddress;
+
+	ss_iso_sink_desc.wMaxPacketSize = isoc_maxpacket;
+	ss_iso_sink_desc.bInterval = isoc_interval;
+	ss_iso_sink_comp_desc.bmAttributes = isoc_mult;
+	ss_iso_sink_comp_desc.bMaxBurst = isoc_maxburst;
+	ss_iso_sink_comp_desc.wBytesPerInterval =
+		isoc_maxpacket * (isoc_mult + 1) * (isoc_maxburst + 1);
+	ss_iso_sink_desc.bEndpointAddress = fs_iso_sink_desc.bEndpointAddress;
+
+	ret = usb_assign_descriptors(f, fs_source_sink_descs,
+			hs_source_sink_descs, ss_source_sink_descs);
+	if (ret)
+		return ret;
+
+	DBG(cdev, "%s speed %s: IN/%s, OUT/%s, ISO-IN/%s, ISO-OUT/%s\n",
+	    (gadget_is_superspeed(c->cdev->gadget) ? "super" :
+	     (gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full")),
+			f->name, ss->in_ep->name, ss->out_ep->name,
+			ss->iso_in_ep ? ss->iso_in_ep->name : "<none>",
+			ss->iso_out_ep ? ss->iso_out_ep->name : "<none>");
+	return 0;
+}
+
+static void
+sourcesink_free_func(struct usb_function *f)
+{
+	struct f_ss_opts *opts;
+
+	opts = container_of(f->fi, struct f_ss_opts, func_inst);
+
+	mutex_lock(&opts->lock);
+	opts->refcnt--;
+	mutex_unlock(&opts->lock);
+
+	usb_free_all_descriptors(f);
+	kfree(func_to_ss(f));
+}
+
+/* optionally require specific source/sink data patterns  */
+static int check_read_data(struct f_sourcesink *ss, struct usb_request *req)
+{
+	unsigned		i;
+	u8			*buf = req->buf;
+	struct usb_composite_dev *cdev = ss->function.config->cdev;
+
+	if (pattern == 2)
+		return 0;
+
+	for (i = 0; i < req->actual; i++, buf++) {
+		switch (pattern) {
+
+		/* all-zeroes has no synchronization issues */
+		case 0:
+			if (*buf == 0)
+				continue;
+			break;
+
+		/* "mod63" stays in sync with short-terminated transfers,
+		 * OR otherwise when host and gadget agree on how large
+		 * each usb transfer request should be.  Resync is done
+		 * with set_interface or set_config.  (We *WANT* it to
+		 * get quickly out of sync if controllers or their drivers
+		 * stutter for any reason, including buffer duplication...)
+		 */
+		case 1:
+			if (*buf == (u8)(i % 63))
+				continue;
+			break;
+		}
+		ERROR(cdev, "bad OUT byte, buf[%d] = %d\n", i, *buf);
+		usb_ep_set_halt(ss->out_ep);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static void reinit_write_data(struct usb_ep *ep, struct usb_request *req)
+{
+	unsigned	i;
+	u8		*buf = req->buf;
+
+	switch (pattern) {
+	case 0:
+		memset(req->buf, 0, req->length);
+		break;
+	case 1:
+		for  (i = 0; i < req->length; i++)
+			*buf++ = (u8) (i % 63);
+		break;
+	case 2:
+		break;
+	}
+}
+
+static void source_sink_complete(struct usb_ep *ep, struct usb_request *req)
+{
+	struct usb_composite_dev	*cdev;
+	struct f_sourcesink		*ss = ep->driver_data;
+	int				status = req->status;
+
+	/* driver_data will be null if ep has been disabled */
+	if (!ss)
+		return;
+
+	cdev = ss->function.config->cdev;
+
+	switch (status) {
+
+	case 0:				/* normal completion? */
+		if (ep == ss->out_ep) {
+			check_read_data(ss, req);
+			if (pattern != 2)
+				memset(req->buf, 0x55, req->length);
+		}
+		break;
+
+	/* this endpoint is normally active while we're configured */
+	case -ECONNABORTED:		/* hardware forced ep reset */
+	case -ECONNRESET:		/* request dequeued */
+	case -ESHUTDOWN:		/* disconnect from host */
+		VDBG(cdev, "%s gone (%d), %d/%d\n", ep->name, status,
+				req->actual, req->length);
+		if (ep == ss->out_ep)
+			check_read_data(ss, req);
+		free_ep_req(ep, req);
+		return;
+
+	case -EOVERFLOW:		/* buffer overrun on read means that
+					 * we didn't provide a big enough
+					 * buffer.
+					 */
+	default:
+#if 1
+		DBG(cdev, "%s complete --> %d, %d/%d\n", ep->name,
+				status, req->actual, req->length);
+#endif
+	case -EREMOTEIO:		/* short read */
+		break;
+	}
+
+	status = usb_ep_queue(ep, req, GFP_ATOMIC);
+	if (status) {
+		ERROR(cdev, "kill %s:  resubmit %d bytes --> %d\n",
+				ep->name, req->length, status);
+		usb_ep_set_halt(ep);
+		/* FIXME recover later ... somehow */
+	}
+}
+
+static int source_sink_start_ep(struct f_sourcesink *ss, bool is_in,
+		bool is_iso, int speed)
+{
+	struct usb_ep		*ep;
+	struct usb_request	*req;
+	int			i, size, status;
+
+	for (i = 0; i < 8; i++) {
+		if (is_iso) {
+			switch (speed) {
+			case USB_SPEED_SUPER:
+				size = isoc_maxpacket * (isoc_mult + 1) *
+						(isoc_maxburst + 1);
+				break;
+			case USB_SPEED_HIGH:
+				size = isoc_maxpacket * (isoc_mult + 1);
+				break;
+			default:
+				size = isoc_maxpacket > 1023 ?
+						1023 : isoc_maxpacket;
+				break;
+			}
+			ep = is_in ? ss->iso_in_ep : ss->iso_out_ep;
+			req = ss_alloc_ep_req(ep, size);
+		} else {
+			ep = is_in ? ss->in_ep : ss->out_ep;
+			req = ss_alloc_ep_req(ep, 0);
+		}
+
+		if (!req)
+			return -ENOMEM;
+
+		req->complete = source_sink_complete;
+		if (is_in)
+			reinit_write_data(ep, req);
+		else if (pattern != 2)
+			memset(req->buf, 0x55, req->length);
+
+		status = usb_ep_queue(ep, req, GFP_ATOMIC);
+		if (status) {
+			struct usb_composite_dev	*cdev;
+
+			cdev = ss->function.config->cdev;
+			ERROR(cdev, "start %s%s %s --> %d\n",
+			      is_iso ? "ISO-" : "", is_in ? "IN" : "OUT",
+			      ep->name, status);
+			free_ep_req(ep, req);
+		}
+
+		if (!is_iso)
+			break;
+	}
+
+	return status;
+}
+
+static void disable_source_sink(struct f_sourcesink *ss)
+{
+	struct usb_composite_dev	*cdev;
+
+	cdev = ss->function.config->cdev;
+	disable_endpoints(cdev, ss->in_ep, ss->out_ep, ss->iso_in_ep,
+			ss->iso_out_ep);
+	VDBG(cdev, "%s disabled\n", ss->function.name);
+}
+
+static int
+enable_source_sink(struct usb_composite_dev *cdev, struct f_sourcesink *ss,
+		int alt)
+{
+	int					result = 0;
+	int					speed = cdev->gadget->speed;
+	struct usb_ep				*ep;
+
+	/* one bulk endpoint writes (sources) zeroes IN (to the host) */
+	ep = ss->in_ep;
+	result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
+	if (result)
+		return result;
+	result = usb_ep_enable(ep);
+	if (result < 0)
+		return result;
+	ep->driver_data = ss;
+
+	result = source_sink_start_ep(ss, true, false, speed);
+	if (result < 0) {
+fail:
+		ep = ss->in_ep;
+		usb_ep_disable(ep);
+		ep->driver_data = NULL;
+		return result;
+	}
+
+	/* one bulk endpoint reads (sinks) anything OUT (from the host) */
+	ep = ss->out_ep;
+	result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
+	if (result)
+		goto fail;
+	result = usb_ep_enable(ep);
+	if (result < 0)
+		goto fail;
+	ep->driver_data = ss;
+
+	result = source_sink_start_ep(ss, false, false, speed);
+	if (result < 0) {
+fail2:
+		ep = ss->out_ep;
+		usb_ep_disable(ep);
+		ep->driver_data = NULL;
+		goto fail;
+	}
+
+	if (alt == 0)
+		goto out;
+
+	/* one iso endpoint writes (sources) zeroes IN (to the host) */
+	ep = ss->iso_in_ep;
+	if (ep) {
+		result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
+		if (result)
+			goto fail2;
+		result = usb_ep_enable(ep);
+		if (result < 0)
+			goto fail2;
+		ep->driver_data = ss;
+
+		result = source_sink_start_ep(ss, true, true, speed);
+		if (result < 0) {
+fail3:
+			ep = ss->iso_in_ep;
+			if (ep) {
+				usb_ep_disable(ep);
+				ep->driver_data = NULL;
+			}
+			goto fail2;
+		}
+	}
+
+	/* one iso endpoint reads (sinks) anything OUT (from the host) */
+	ep = ss->iso_out_ep;
+	if (ep) {
+		result = config_ep_by_speed(cdev->gadget, &(ss->function), ep);
+		if (result)
+			goto fail3;
+		result = usb_ep_enable(ep);
+		if (result < 0)
+			goto fail3;
+		ep->driver_data = ss;
+
+		result = source_sink_start_ep(ss, false, true, speed);
+		if (result < 0) {
+			usb_ep_disable(ep);
+			ep->driver_data = NULL;
+			goto fail3;
+		}
+	}
+out:
+	ss->cur_alt = alt;
+
+	DBG(cdev, "%s enabled, alt intf %d\n", ss->function.name, alt);
+	return result;
+}
+
+static int sourcesink_set_alt(struct usb_function *f,
+		unsigned intf, unsigned alt)
+{
+	struct f_sourcesink		*ss = func_to_ss(f);
+	struct usb_composite_dev	*cdev = f->config->cdev;
+
+	if (ss->in_ep->driver_data)
+		disable_source_sink(ss);
+	return enable_source_sink(cdev, ss, alt);
+}
+
+static int sourcesink_get_alt(struct usb_function *f, unsigned intf)
+{
+	struct f_sourcesink		*ss = func_to_ss(f);
+
+	return ss->cur_alt;
+}
+
+static void sourcesink_disable(struct usb_function *f)
+{
+	struct f_sourcesink	*ss = func_to_ss(f);
+
+	disable_source_sink(ss);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int sourcesink_setup(struct usb_function *f,
+		const struct usb_ctrlrequest *ctrl)
+{
+	struct usb_configuration        *c = f->config;
+	struct usb_request	*req = c->cdev->req;
+	int			value = -EOPNOTSUPP;
+	u16			w_index = le16_to_cpu(ctrl->wIndex);
+	u16			w_value = le16_to_cpu(ctrl->wValue);
+	u16			w_length = le16_to_cpu(ctrl->wLength);
+
+	req->length = USB_COMP_EP0_BUFSIZ;
+
+	/* composite driver infrastructure handles everything except
+	 * the two control test requests.
+	 */
+	switch (ctrl->bRequest) {
+
+	/*
+	 * These are the same vendor-specific requests supported by
+	 * Intel's USB 2.0 compliance test devices.  We exceed that
+	 * device spec by allowing multiple-packet requests.
+	 *
+	 * NOTE:  the Control-OUT data stays in req->buf ... better
+	 * would be copying it into a scratch buffer, so that other
+	 * requests may safely intervene.
+	 */
+	case 0x5b:	/* control WRITE test -- fill the buffer */
+		if (ctrl->bRequestType != (USB_DIR_OUT|USB_TYPE_VENDOR))
+			goto unknown;
+		if (w_value || w_index)
+			break;
+		/* just read that many bytes into the buffer */
+		if (w_length > req->length)
+			break;
+		value = w_length;
+		break;
+	case 0x5c:	/* control READ test -- return the buffer */
+		if (ctrl->bRequestType != (USB_DIR_IN|USB_TYPE_VENDOR))
+			goto unknown;
+		if (w_value || w_index)
+			break;
+		/* expect those bytes are still in the buffer; send back */
+		if (w_length > req->length)
+			break;
+		value = w_length;
+		break;
+
+	default:
+unknown:
+		VDBG(c->cdev,
+			"unknown control req%02x.%02x v%04x i%04x l%d\n",
+			ctrl->bRequestType, ctrl->bRequest,
+			w_value, w_index, w_length);
+	}
+
+	/* respond with data transfer or status phase? */
+	if (value >= 0) {
+		VDBG(c->cdev, "source/sink req%02x.%02x v%04x i%04x l%d\n",
+			ctrl->bRequestType, ctrl->bRequest,
+			w_value, w_index, w_length);
+		req->zero = 0;
+		req->length = value;
+		value = usb_ep_queue(c->cdev->gadget->ep0, req, GFP_ATOMIC);
+		if (value < 0)
+			ERROR(c->cdev, "source/sink response, err %d\n",
+					value);
+	}
+
+	/* device either stalls (value < 0) or reports success */
+	return value;
+}
+
+static struct usb_function *source_sink_alloc_func(
+		struct usb_function_instance *fi)
+{
+	struct f_sourcesink     *ss;
+	struct f_ss_opts	*ss_opts;
+
+	ss = kzalloc(sizeof(*ss), GFP_KERNEL);
+	if (!ss)
+		return NULL;
+
+	ss_opts =  container_of(fi, struct f_ss_opts, func_inst);
+
+	mutex_lock(&ss_opts->lock);
+	ss_opts->refcnt++;
+	mutex_unlock(&ss_opts->lock);
+
+	pattern = ss_opts->pattern;
+	isoc_interval = ss_opts->isoc_interval;
+	isoc_maxpacket = ss_opts->isoc_maxpacket;
+	isoc_mult = ss_opts->isoc_mult;
+	isoc_maxburst = ss_opts->isoc_maxburst;
+	buflen = ss_opts->bulk_buflen;
+
+	ss->function.name = "source/sink";
+	ss->function.bind = sourcesink_bind;
+	ss->function.set_alt = sourcesink_set_alt;
+	ss->function.get_alt = sourcesink_get_alt;
+	ss->function.disable = sourcesink_disable;
+	ss->function.setup = sourcesink_setup;
+	ss->function.strings = sourcesink_strings;
+
+	ss->function.free_func = sourcesink_free_func;
+
+	return &ss->function;
+}
+
+static inline struct f_ss_opts *to_f_ss_opts(struct config_item *item)
+{
+	return container_of(to_config_group(item), struct f_ss_opts,
+			    func_inst.group);
+}
+
+CONFIGFS_ATTR_STRUCT(f_ss_opts);
+CONFIGFS_ATTR_OPS(f_ss_opts);
+
+static void ss_attr_release(struct config_item *item)
+{
+	struct f_ss_opts *ss_opts = to_f_ss_opts(item);
+
+	usb_put_function_instance(&ss_opts->func_inst);
+}
+
+static struct configfs_item_operations ss_item_ops = {
+	.release		= ss_attr_release,
+	.show_attribute		= f_ss_opts_attr_show,
+	.store_attribute	= f_ss_opts_attr_store,
+};
+
+static ssize_t f_ss_opts_pattern_show(struct f_ss_opts *opts, char *page)
+{
+	int result;
+
+	mutex_lock(&opts->lock);
+	result = sprintf(page, "%d", opts->pattern);
+	mutex_unlock(&opts->lock);
+
+	return result;
+}
+
+static ssize_t f_ss_opts_pattern_store(struct f_ss_opts *opts,
+				       const char *page, size_t len)
+{
+	int ret;
+	u8 num;
+
+	mutex_lock(&opts->lock);
+	if (opts->refcnt) {
+		ret = -EBUSY;
+		goto end;
+	}
+
+	ret = kstrtou8(page, 0, &num);
+	if (ret)
+		goto end;
+
+	if (num != 0 && num != 1 && num != 2) {
+		ret = -EINVAL;
+		goto end;
+	}
+
+	opts->pattern = num;
+	ret = len;
+end:
+	mutex_unlock(&opts->lock);
+	return ret;
+}
+
+static struct f_ss_opts_attribute f_ss_opts_pattern =
+	__CONFIGFS_ATTR(pattern, S_IRUGO | S_IWUSR,
+			f_ss_opts_pattern_show,
+			f_ss_opts_pattern_store);
+
+static ssize_t f_ss_opts_isoc_interval_show(struct f_ss_opts *opts, char *page)
+{
+	int result;
+
+	mutex_lock(&opts->lock);
+	result = sprintf(page, "%d", opts->isoc_interval);
+	mutex_unlock(&opts->lock);
+
+	return result;
+}
+
+static ssize_t f_ss_opts_isoc_interval_store(struct f_ss_opts *opts,
+				       const char *page, size_t len)
+{
+	int ret;
+	u8 num;
+
+	mutex_lock(&opts->lock);
+	if (opts->refcnt) {
+		ret = -EBUSY;
+		goto end;
+	}
+
+	ret = kstrtou8(page, 0, &num);
+	if (ret)
+		goto end;
+
+	if (num > 16) {
+		ret = -EINVAL;
+		goto end;
+	}
+
+	opts->isoc_interval = num;
+	ret = len;
+end:
+	mutex_unlock(&opts->lock);
+	return ret;
+}
+
+static struct f_ss_opts_attribute f_ss_opts_isoc_interval =
+	__CONFIGFS_ATTR(isoc_interval, S_IRUGO | S_IWUSR,
+			f_ss_opts_isoc_interval_show,
+			f_ss_opts_isoc_interval_store);
+
+static ssize_t f_ss_opts_isoc_maxpacket_show(struct f_ss_opts *opts, char *page)
+{
+	int result;
+
+	mutex_lock(&opts->lock);
+	result = sprintf(page, "%d", opts->isoc_maxpacket);
+	mutex_unlock(&opts->lock);
+
+	return result;
+}
+
+static ssize_t f_ss_opts_isoc_maxpacket_store(struct f_ss_opts *opts,
+				       const char *page, size_t len)
+{
+	int ret;
+	u16 num;
+
+	mutex_lock(&opts->lock);
+	if (opts->refcnt) {
+		ret = -EBUSY;
+		goto end;
+	}
+
+	ret = kstrtou16(page, 0, &num);
+	if (ret)
+		goto end;
+
+	if (num > 1024) {
+		ret = -EINVAL;
+		goto end;
+	}
+
+	opts->isoc_maxpacket = num;
+	ret = len;
+end:
+	mutex_unlock(&opts->lock);
+	return ret;
+}
+
+static struct f_ss_opts_attribute f_ss_opts_isoc_maxpacket =
+	__CONFIGFS_ATTR(isoc_maxpacket, S_IRUGO | S_IWUSR,
+			f_ss_opts_isoc_maxpacket_show,
+			f_ss_opts_isoc_maxpacket_store);
+
+static ssize_t f_ss_opts_isoc_mult_show(struct f_ss_opts *opts, char *page)
+{
+	int result;
+
+	mutex_lock(&opts->lock);
+	result = sprintf(page, "%d", opts->isoc_mult);
+	mutex_unlock(&opts->lock);
+
+	return result;
+}
+
+static ssize_t f_ss_opts_isoc_mult_store(struct f_ss_opts *opts,
+				       const char *page, size_t len)
+{
+	int ret;
+	u8 num;
+
+	mutex_lock(&opts->lock);
+	if (opts->refcnt) {
+		ret = -EBUSY;
+		goto end;
+	}
+
+	ret = kstrtou8(page, 0, &num);
+	if (ret)
+		goto end;
+
+	if (num > 2) {
+		ret = -EINVAL;
+		goto end;
+	}
+
+	opts->isoc_mult = num;
+	ret = len;
+end:
+	mutex_unlock(&opts->lock);
+	return ret;
+}
+
+static struct f_ss_opts_attribute f_ss_opts_isoc_mult =
+	__CONFIGFS_ATTR(isoc_mult, S_IRUGO | S_IWUSR,
+			f_ss_opts_isoc_mult_show,
+			f_ss_opts_isoc_mult_store);
+
+static ssize_t f_ss_opts_isoc_maxburst_show(struct f_ss_opts *opts, char *page)
+{
+	int result;
+
+	mutex_lock(&opts->lock);
+	result = sprintf(page, "%d", opts->isoc_maxburst);
+	mutex_unlock(&opts->lock);
+
+	return result;
+}
+
+static ssize_t f_ss_opts_isoc_maxburst_store(struct f_ss_opts *opts,
+				       const char *page, size_t len)
+{
+	int ret;
+	u8 num;
+
+	mutex_lock(&opts->lock);
+	if (opts->refcnt) {
+		ret = -EBUSY;
+		goto end;
+	}
+
+	ret = kstrtou8(page, 0, &num);
+	if (ret)
+		goto end;
+
+	if (num > 15) {
+		ret = -EINVAL;
+		goto end;
+	}
+
+	opts->isoc_maxburst = num;
+	ret = len;
+end:
+	mutex_unlock(&opts->lock);
+	return ret;
+}
+
+static struct f_ss_opts_attribute f_ss_opts_isoc_maxburst =
+	__CONFIGFS_ATTR(isoc_maxburst, S_IRUGO | S_IWUSR,
+			f_ss_opts_isoc_maxburst_show,
+			f_ss_opts_isoc_maxburst_store);
+
+static ssize_t f_ss_opts_bulk_buflen_show(struct f_ss_opts *opts, char *page)
+{
+	int result;
+
+	mutex_lock(&opts->lock);
+	result = sprintf(page, "%d", opts->bulk_buflen);
+	mutex_unlock(&opts->lock);
+
+	return result;
+}
+
+static ssize_t f_ss_opts_bulk_buflen_store(struct f_ss_opts *opts,
+					   const char *page, size_t len)
+{
+	int ret;
+	u32 num;
+
+	mutex_lock(&opts->lock);
+	if (opts->refcnt) {
+		ret = -EBUSY;
+		goto end;
+	}
+
+	ret = kstrtou32(page, 0, &num);
+	if (ret)
+		goto end;
+
+	opts->bulk_buflen = num;
+	ret = len;
+end:
+	mutex_unlock(&opts->lock);
+	return ret;
+}
+
+static struct f_ss_opts_attribute f_ss_opts_bulk_buflen =
+	__CONFIGFS_ATTR(buflen, S_IRUGO | S_IWUSR,
+			f_ss_opts_bulk_buflen_show,
+			f_ss_opts_bulk_buflen_store);
+
+static struct configfs_attribute *ss_attrs[] = {
+	&f_ss_opts_pattern.attr,
+	&f_ss_opts_isoc_interval.attr,
+	&f_ss_opts_isoc_maxpacket.attr,
+	&f_ss_opts_isoc_mult.attr,
+	&f_ss_opts_isoc_maxburst.attr,
+	&f_ss_opts_bulk_buflen.attr,
+	NULL,
+};
+
+static struct config_item_type ss_func_type = {
+	.ct_item_ops    = &ss_item_ops,
+	.ct_attrs	= ss_attrs,
+	.ct_owner       = THIS_MODULE,
+};
+
+static void source_sink_free_instance(struct usb_function_instance *fi)
+{
+	struct f_ss_opts *ss_opts;
+
+	ss_opts = container_of(fi, struct f_ss_opts, func_inst);
+	kfree(ss_opts);
+}
+
+static struct usb_function_instance *source_sink_alloc_inst(void)
+{
+	struct f_ss_opts *ss_opts;
+
+	ss_opts = kzalloc(sizeof(*ss_opts), GFP_KERNEL);
+	if (!ss_opts)
+		return ERR_PTR(-ENOMEM);
+	mutex_init(&ss_opts->lock);
+	ss_opts->func_inst.free_func_inst = source_sink_free_instance;
+	ss_opts->isoc_interval = GZERO_ISOC_INTERVAL;
+	ss_opts->isoc_maxpacket = GZERO_ISOC_MAXPACKET;
+	ss_opts->bulk_buflen = GZERO_BULK_BUFLEN;
+
+	config_group_init_type_name(&ss_opts->func_inst.group, "",
+				    &ss_func_type);
+
+	return &ss_opts->func_inst;
+}
+DECLARE_USB_FUNCTION(SourceSink, source_sink_alloc_inst,
+		source_sink_alloc_func);
+
+static int __init sslb_modinit(void)
+{
+	int ret;
+
+	ret = usb_function_register(&SourceSinkusb_func);
+	if (ret)
+		return ret;
+	ret = lb_modinit();
+	if (ret)
+		usb_function_unregister(&SourceSinkusb_func);
+	return ret;
+}
+static void __exit sslb_modexit(void)
+{
+	usb_function_unregister(&SourceSinkusb_func);
+	lb_modexit();
+}
+module_init(sslb_modinit);
+module_exit(sslb_modexit);
+
+MODULE_LICENSE("GPL");