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");