Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1103 insertions, 0 deletions

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
new file mode 100644
index 000000000..0410f05cc
--- /dev/null
+++ b/drivers/usb/core/config.c
@@ -0,0 +1,1103 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Released under the GPLv2 only.
+ */
+
+#include <linux/usb.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/hcd.h>
+#include <linux/usb/quirks.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <asm/byteorder.h>
+#include "usb.h"
+
+
+#define USB_MAXALTSETTING		128	/* Hard limit */
+
+#define USB_MAXCONFIG			8	/* Arbitrary limit */
+
+
+static inline const char *plural(int n)
+{
+	return (n == 1 ? "" : "s");
+}
+
+static int find_next_descriptor(unsigned char *buffer, int size,
+    int dt1, int dt2, int *num_skipped)
+{
+	struct usb_descriptor_header *h;
+	int n = 0;
+	unsigned char *buffer0 = buffer;
+
+	/* Find the next descriptor of type dt1 or dt2 */
+	while (size > 0) {
+		h = (struct usb_descriptor_header *) buffer;
+		if (h->bDescriptorType == dt1 || h->bDescriptorType == dt2)
+			break;
+		buffer += h->bLength;
+		size -= h->bLength;
+		++n;
+	}
+
+	/* Store the number of descriptors skipped and return the
+	 * number of bytes skipped */
+	if (num_skipped)
+		*num_skipped = n;
+	return buffer - buffer0;
+}
+
+static void usb_parse_ssp_isoc_endpoint_companion(struct device *ddev,
+		int cfgno, int inum, int asnum, struct usb_host_endpoint *ep,
+		unsigned char *buffer, int size)
+{
+	struct usb_ssp_isoc_ep_comp_descriptor *desc;
+
+	/*
+	 * The SuperSpeedPlus Isoc endpoint companion descriptor immediately
+	 * follows the SuperSpeed Endpoint Companion descriptor
+	 */
+	desc = (struct usb_ssp_isoc_ep_comp_descriptor *) buffer;
+	if (desc->bDescriptorType != USB_DT_SSP_ISOC_ENDPOINT_COMP ||
+	    size < USB_DT_SSP_ISOC_EP_COMP_SIZE) {
+		dev_warn(ddev, "Invalid SuperSpeedPlus isoc endpoint companion"
+			 "for config %d interface %d altsetting %d ep %d.\n",
+			 cfgno, inum, asnum, ep->desc.bEndpointAddress);
+		return;
+	}
+	memcpy(&ep->ssp_isoc_ep_comp, desc, USB_DT_SSP_ISOC_EP_COMP_SIZE);
+}
+
+static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno,
+		int inum, int asnum, struct usb_host_endpoint *ep,
+		unsigned char *buffer, int size)
+{
+	struct usb_ss_ep_comp_descriptor *desc;
+	int max_tx;
+
+	/* The SuperSpeed endpoint companion descriptor is supposed to
+	 * be the first thing immediately following the endpoint descriptor.
+	 */
+	desc = (struct usb_ss_ep_comp_descriptor *) buffer;
+
+	if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP ||
+			size < USB_DT_SS_EP_COMP_SIZE) {
+		dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
+				" interface %d altsetting %d ep %d: "
+				"using minimum values\n",
+				cfgno, inum, asnum, ep->desc.bEndpointAddress);
+
+		/* Fill in some default values.
+		 * Leave bmAttributes as zero, which will mean no streams for
+		 * bulk, and isoc won't support multiple bursts of packets.
+		 * With bursts of only one packet, and a Mult of 1, the max
+		 * amount of data moved per endpoint service interval is one
+		 * packet.
+		 */
+		ep->ss_ep_comp.bLength = USB_DT_SS_EP_COMP_SIZE;
+		ep->ss_ep_comp.bDescriptorType = USB_DT_SS_ENDPOINT_COMP;
+		if (usb_endpoint_xfer_isoc(&ep->desc) ||
+				usb_endpoint_xfer_int(&ep->desc))
+			ep->ss_ep_comp.wBytesPerInterval =
+					ep->desc.wMaxPacketSize;
+		return;
+	}
+	buffer += desc->bLength;
+	size -= desc->bLength;
+	memcpy(&ep->ss_ep_comp, desc, USB_DT_SS_EP_COMP_SIZE);
+
+	/* Check the various values */
+	if (usb_endpoint_xfer_control(&ep->desc) && desc->bMaxBurst != 0) {
+		dev_warn(ddev, "Control endpoint with bMaxBurst = %d in "
+				"config %d interface %d altsetting %d ep %d: "
+				"setting to zero\n", desc->bMaxBurst,
+				cfgno, inum, asnum, ep->desc.bEndpointAddress);
+		ep->ss_ep_comp.bMaxBurst = 0;
+	} else if (desc->bMaxBurst > 15) {
+		dev_warn(ddev, "Endpoint with bMaxBurst = %d in "
+				"config %d interface %d altsetting %d ep %d: "
+				"setting to 15\n", desc->bMaxBurst,
+				cfgno, inum, asnum, ep->desc.bEndpointAddress);
+		ep->ss_ep_comp.bMaxBurst = 15;
+	}
+
+	if ((usb_endpoint_xfer_control(&ep->desc) ||
+			usb_endpoint_xfer_int(&ep->desc)) &&
+				desc->bmAttributes != 0) {
+		dev_warn(ddev, "%s endpoint with bmAttributes = %d in "
+				"config %d interface %d altsetting %d ep %d: "
+				"setting to zero\n",
+				usb_endpoint_xfer_control(&ep->desc) ? "Control" : "Bulk",
+				desc->bmAttributes,
+				cfgno, inum, asnum, ep->desc.bEndpointAddress);
+		ep->ss_ep_comp.bmAttributes = 0;
+	} else if (usb_endpoint_xfer_bulk(&ep->desc) &&
+			desc->bmAttributes > 16) {
+		dev_warn(ddev, "Bulk endpoint with more than 65536 streams in "
+				"config %d interface %d altsetting %d ep %d: "
+				"setting to max\n",
+				cfgno, inum, asnum, ep->desc.bEndpointAddress);
+		ep->ss_ep_comp.bmAttributes = 16;
+	} else if (usb_endpoint_xfer_isoc(&ep->desc) &&
+		   !USB_SS_SSP_ISOC_COMP(desc->bmAttributes) &&
+		   USB_SS_MULT(desc->bmAttributes) > 3) {
+		dev_warn(ddev, "Isoc endpoint has Mult of %d in "
+				"config %d interface %d altsetting %d ep %d: "
+				"setting to 3\n",
+				USB_SS_MULT(desc->bmAttributes),
+				cfgno, inum, asnum, ep->desc.bEndpointAddress);
+		ep->ss_ep_comp.bmAttributes = 2;
+	}
+
+	if (usb_endpoint_xfer_isoc(&ep->desc))
+		max_tx = (desc->bMaxBurst + 1) *
+			(USB_SS_MULT(desc->bmAttributes)) *
+			usb_endpoint_maxp(&ep->desc);
+	else if (usb_endpoint_xfer_int(&ep->desc))
+		max_tx = usb_endpoint_maxp(&ep->desc) *
+			(desc->bMaxBurst + 1);
+	else
+		max_tx = 999999;
+	if (le16_to_cpu(desc->wBytesPerInterval) > max_tx) {
+		dev_warn(ddev, "%s endpoint with wBytesPerInterval of %d in "
+				"config %d interface %d altsetting %d ep %d: "
+				"setting to %d\n",
+				usb_endpoint_xfer_isoc(&ep->desc) ? "Isoc" : "Int",
+				le16_to_cpu(desc->wBytesPerInterval),
+				cfgno, inum, asnum, ep->desc.bEndpointAddress,
+				max_tx);
+		ep->ss_ep_comp.wBytesPerInterval = cpu_to_le16(max_tx);
+	}
+	/* Parse a possible SuperSpeedPlus isoc ep companion descriptor */
+	if (usb_endpoint_xfer_isoc(&ep->desc) &&
+	    USB_SS_SSP_ISOC_COMP(desc->bmAttributes))
+		usb_parse_ssp_isoc_endpoint_companion(ddev, cfgno, inum, asnum,
+							ep, buffer, size);
+}
+
+static const unsigned short low_speed_maxpacket_maxes[4] = {
+	[USB_ENDPOINT_XFER_CONTROL] = 8,
+	[USB_ENDPOINT_XFER_ISOC] = 0,
+	[USB_ENDPOINT_XFER_BULK] = 0,
+	[USB_ENDPOINT_XFER_INT] = 8,
+};
+static const unsigned short full_speed_maxpacket_maxes[4] = {
+	[USB_ENDPOINT_XFER_CONTROL] = 64,
+	[USB_ENDPOINT_XFER_ISOC] = 1023,
+	[USB_ENDPOINT_XFER_BULK] = 64,
+	[USB_ENDPOINT_XFER_INT] = 64,
+};
+static const unsigned short high_speed_maxpacket_maxes[4] = {
+	[USB_ENDPOINT_XFER_CONTROL] = 64,
+	[USB_ENDPOINT_XFER_ISOC] = 1024,
+
+	/* Bulk should be 512, but some devices use 1024: we will warn below */
+	[USB_ENDPOINT_XFER_BULK] = 1024,
+	[USB_ENDPOINT_XFER_INT] = 1024,
+};
+static const unsigned short super_speed_maxpacket_maxes[4] = {
+	[USB_ENDPOINT_XFER_CONTROL] = 512,
+	[USB_ENDPOINT_XFER_ISOC] = 1024,
+	[USB_ENDPOINT_XFER_BULK] = 1024,
+	[USB_ENDPOINT_XFER_INT] = 1024,
+};
+
+static bool endpoint_is_duplicate(struct usb_endpoint_descriptor *e1,
+		struct usb_endpoint_descriptor *e2)
+{
+	if (e1->bEndpointAddress == e2->bEndpointAddress)
+		return true;
+
+	if (usb_endpoint_xfer_control(e1) || usb_endpoint_xfer_control(e2)) {
+		if (usb_endpoint_num(e1) == usb_endpoint_num(e2))
+			return true;
+	}
+
+	return false;
+}
+
+/*
+ * Check for duplicate endpoint addresses in other interfaces and in the
+ * altsetting currently being parsed.
+ */
+static bool config_endpoint_is_duplicate(struct usb_host_config *config,
+		int inum, int asnum, struct usb_endpoint_descriptor *d)
+{
+	struct usb_endpoint_descriptor *epd;
+	struct usb_interface_cache *intfc;
+	struct usb_host_interface *alt;
+	int i, j, k;
+
+	for (i = 0; i < config->desc.bNumInterfaces; ++i) {
+		intfc = config->intf_cache[i];
+
+		for (j = 0; j < intfc->num_altsetting; ++j) {
+			alt = &intfc->altsetting[j];
+
+			if (alt->desc.bInterfaceNumber == inum &&
+					alt->desc.bAlternateSetting != asnum)
+				continue;
+
+			for (k = 0; k < alt->desc.bNumEndpoints; ++k) {
+				epd = &alt->endpoint[k].desc;
+
+				if (endpoint_is_duplicate(epd, d))
+					return true;
+			}
+		}
+	}
+
+	return false;
+}
+
+static int usb_parse_endpoint(struct device *ddev, int cfgno,
+		struct usb_host_config *config, int inum, int asnum,
+		struct usb_host_interface *ifp, int num_ep,
+		unsigned char *buffer, int size)
+{
+	struct usb_device *udev = to_usb_device(ddev);
+	unsigned char *buffer0 = buffer;
+	struct usb_endpoint_descriptor *d;
+	struct usb_host_endpoint *endpoint;
+	int n, i, j, retval;
+	unsigned int maxp;
+	const unsigned short *maxpacket_maxes;
+
+	d = (struct usb_endpoint_descriptor *) buffer;
+	buffer += d->bLength;
+	size -= d->bLength;
+
+	if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
+		n = USB_DT_ENDPOINT_AUDIO_SIZE;
+	else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
+		n = USB_DT_ENDPOINT_SIZE;
+	else {
+		dev_warn(ddev, "config %d interface %d altsetting %d has an "
+		    "invalid endpoint descriptor of length %d, skipping\n",
+		    cfgno, inum, asnum, d->bLength);
+		goto skip_to_next_endpoint_or_interface_descriptor;
+	}
+
+	i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
+	if (i >= 16 || i == 0) {
+		dev_warn(ddev, "config %d interface %d altsetting %d has an "
+		    "invalid endpoint with address 0x%X, skipping\n",
+		    cfgno, inum, asnum, d->bEndpointAddress);
+		goto skip_to_next_endpoint_or_interface_descriptor;
+	}
+
+	/* Only store as many endpoints as we have room for */
+	if (ifp->desc.bNumEndpoints >= num_ep)
+		goto skip_to_next_endpoint_or_interface_descriptor;
+
+	/* Check for duplicate endpoint addresses */
+	if (config_endpoint_is_duplicate(config, inum, asnum, d)) {
+		dev_warn(ddev, "config %d interface %d altsetting %d has a duplicate endpoint with address 0x%X, skipping\n",
+				cfgno, inum, asnum, d->bEndpointAddress);
+		goto skip_to_next_endpoint_or_interface_descriptor;
+	}
+
+	/* Ignore blacklisted endpoints */
+	if (udev->quirks & USB_QUIRK_ENDPOINT_BLACKLIST) {
+		if (usb_endpoint_is_blacklisted(udev, ifp, d)) {
+			dev_warn(ddev, "config %d interface %d altsetting %d has a blacklisted endpoint with address 0x%X, skipping\n",
+					cfgno, inum, asnum,
+					d->bEndpointAddress);
+			goto skip_to_next_endpoint_or_interface_descriptor;
+		}
+	}
+
+	endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
+	++ifp->desc.bNumEndpoints;
+
+	memcpy(&endpoint->desc, d, n);
+	INIT_LIST_HEAD(&endpoint->urb_list);
+
+	/*
+	 * Fix up bInterval values outside the legal range.
+	 * Use 10 or 8 ms if no proper value can be guessed.
+	 */
+	i = 0;		/* i = min, j = max, n = default */
+	j = 255;
+	if (usb_endpoint_xfer_int(d)) {
+		i = 1;
+		switch (to_usb_device(ddev)->speed) {
+		case USB_SPEED_SUPER_PLUS:
+		case USB_SPEED_SUPER:
+		case USB_SPEED_HIGH:
+			/*
+			 * Many device manufacturers are using full-speed
+			 * bInterval values in high-speed interrupt endpoint
+			 * descriptors. Try to fix those and fall back to an
+			 * 8-ms default value otherwise.
+			 */
+			n = fls(d->bInterval*8);
+			if (n == 0)
+				n = 7;	/* 8 ms = 2^(7-1) uframes */
+			j = 16;
+
+			/*
+			 * Adjust bInterval for quirked devices.
+			 */
+			/*
+			 * This quirk fixes bIntervals reported in ms.
+			 */
+			if (to_usb_device(ddev)->quirks &
+				USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL) {
+				n = clamp(fls(d->bInterval) + 3, i, j);
+				i = j = n;
+			}
+			/*
+			 * This quirk fixes bIntervals reported in
+			 * linear microframes.
+			 */
+			if (to_usb_device(ddev)->quirks &
+				USB_QUIRK_LINEAR_UFRAME_INTR_BINTERVAL) {
+				n = clamp(fls(d->bInterval), i, j);
+				i = j = n;
+			}
+			break;
+		default:		/* USB_SPEED_FULL or _LOW */
+			/*
+			 * For low-speed, 10 ms is the official minimum.
+			 * But some "overclocked" devices might want faster
+			 * polling so we'll allow it.
+			 */
+			n = 10;
+			break;
+		}
+	} else if (usb_endpoint_xfer_isoc(d)) {
+		i = 1;
+		j = 16;
+		switch (to_usb_device(ddev)->speed) {
+		case USB_SPEED_HIGH:
+			n = 7;		/* 8 ms = 2^(7-1) uframes */
+			break;
+		default:		/* USB_SPEED_FULL */
+			n = 4;		/* 8 ms = 2^(4-1) frames */
+			break;
+		}
+	}
+	if (d->bInterval < i || d->bInterval > j) {
+		dev_warn(ddev, "config %d interface %d altsetting %d "
+		    "endpoint 0x%X has an invalid bInterval %d, "
+		    "changing to %d\n",
+		    cfgno, inum, asnum,
+		    d->bEndpointAddress, d->bInterval, n);
+		endpoint->desc.bInterval = n;
+	}
+
+	/* Some buggy low-speed devices have Bulk endpoints, which is
+	 * explicitly forbidden by the USB spec.  In an attempt to make
+	 * them usable, we will try treating them as Interrupt endpoints.
+	 */
+	if (to_usb_device(ddev)->speed == USB_SPEED_LOW &&
+			usb_endpoint_xfer_bulk(d)) {
+		dev_warn(ddev, "config %d interface %d altsetting %d "
+		    "endpoint 0x%X is Bulk; changing to Interrupt\n",
+		    cfgno, inum, asnum, d->bEndpointAddress);
+		endpoint->desc.bmAttributes = USB_ENDPOINT_XFER_INT;
+		endpoint->desc.bInterval = 1;
+		if (usb_endpoint_maxp(&endpoint->desc) > 8)
+			endpoint->desc.wMaxPacketSize = cpu_to_le16(8);
+	}
+
+	/*
+	 * Validate the wMaxPacketSize field.
+	 * Some devices have isochronous endpoints in altsetting 0;
+	 * the USB-2 spec requires such endpoints to have wMaxPacketSize = 0
+	 * (see the end of section 5.6.3), so don't warn about them.
+	 */
+	maxp = le16_to_cpu(endpoint->desc.wMaxPacketSize);
+	if (maxp == 0 && !(usb_endpoint_xfer_isoc(d) && asnum == 0)) {
+		dev_warn(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid wMaxPacketSize 0\n",
+		    cfgno, inum, asnum, d->bEndpointAddress);
+	}
+
+	/* Find the highest legal maxpacket size for this endpoint */
+	i = 0;		/* additional transactions per microframe */
+	switch (to_usb_device(ddev)->speed) {
+	case USB_SPEED_LOW:
+		maxpacket_maxes = low_speed_maxpacket_maxes;
+		break;
+	case USB_SPEED_FULL:
+		maxpacket_maxes = full_speed_maxpacket_maxes;
+		break;
+	case USB_SPEED_HIGH:
+		/* Multiple-transactions bits are allowed only for HS periodic endpoints */
+		if (usb_endpoint_xfer_int(d) || usb_endpoint_xfer_isoc(d)) {
+			i = maxp & USB_EP_MAXP_MULT_MASK;
+			maxp &= ~i;
+		}
+		/* fallthrough */
+	default:
+		maxpacket_maxes = high_speed_maxpacket_maxes;
+		break;
+	case USB_SPEED_SUPER:
+	case USB_SPEED_SUPER_PLUS:
+		maxpacket_maxes = super_speed_maxpacket_maxes;
+		break;
+	}
+	j = maxpacket_maxes[usb_endpoint_type(&endpoint->desc)];
+
+	if (maxp > j) {
+		dev_warn(ddev, "config %d interface %d altsetting %d endpoint 0x%X has invalid maxpacket %d, setting to %d\n",
+		    cfgno, inum, asnum, d->bEndpointAddress, maxp, j);
+		maxp = j;
+		endpoint->desc.wMaxPacketSize = cpu_to_le16(i | maxp);
+	}
+
+	/*
+	 * Some buggy high speed devices have bulk endpoints using
+	 * maxpacket sizes other than 512.  High speed HCDs may not
+	 * be able to handle that particular bug, so let's warn...
+	 */
+	if (to_usb_device(ddev)->speed == USB_SPEED_HIGH
+			&& usb_endpoint_xfer_bulk(d)) {
+		if (maxp != 512)
+			dev_warn(ddev, "config %d interface %d altsetting %d "
+				"bulk endpoint 0x%X has invalid maxpacket %d\n",
+				cfgno, inum, asnum, d->bEndpointAddress,
+				maxp);
+	}
+
+	/* Parse a possible SuperSpeed endpoint companion descriptor */
+	if (to_usb_device(ddev)->speed >= USB_SPEED_SUPER)
+		usb_parse_ss_endpoint_companion(ddev, cfgno,
+				inum, asnum, endpoint, buffer, size);
+
+	/* Skip over any Class Specific or Vendor Specific descriptors;
+	 * find the next endpoint or interface descriptor */
+	endpoint->extra = buffer;
+	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
+			USB_DT_INTERFACE, &n);
+	endpoint->extralen = i;
+	retval = buffer - buffer0 + i;
+	if (n > 0)
+		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
+		    n, plural(n), "endpoint");
+	return retval;
+
+skip_to_next_endpoint_or_interface_descriptor:
+	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
+	    USB_DT_INTERFACE, NULL);
+	return buffer - buffer0 + i;
+}
+
+void usb_release_interface_cache(struct kref *ref)
+{
+	struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
+	int j;
+
+	for (j = 0; j < intfc->num_altsetting; j++) {
+		struct usb_host_interface *alt = &intfc->altsetting[j];
+
+		kfree(alt->endpoint);
+		kfree(alt->string);
+	}
+	kfree(intfc);
+}
+
+static int usb_parse_interface(struct device *ddev, int cfgno,
+    struct usb_host_config *config, unsigned char *buffer, int size,
+    u8 inums[], u8 nalts[])
+{
+	unsigned char *buffer0 = buffer;
+	struct usb_interface_descriptor	*d;
+	int inum, asnum;
+	struct usb_interface_cache *intfc;
+	struct usb_host_interface *alt;
+	int i, n;
+	int len, retval;
+	int num_ep, num_ep_orig;
+
+	d = (struct usb_interface_descriptor *) buffer;
+	buffer += d->bLength;
+	size -= d->bLength;
+
+	if (d->bLength < USB_DT_INTERFACE_SIZE)
+		goto skip_to_next_interface_descriptor;
+
+	/* Which interface entry is this? */
+	intfc = NULL;
+	inum = d->bInterfaceNumber;
+	for (i = 0; i < config->desc.bNumInterfaces; ++i) {
+		if (inums[i] == inum) {
+			intfc = config->intf_cache[i];
+			break;
+		}
+	}
+	if (!intfc || intfc->num_altsetting >= nalts[i])
+		goto skip_to_next_interface_descriptor;
+
+	/* Check for duplicate altsetting entries */
+	asnum = d->bAlternateSetting;
+	for ((i = 0, alt = &intfc->altsetting[0]);
+	      i < intfc->num_altsetting;
+	     (++i, ++alt)) {
+		if (alt->desc.bAlternateSetting == asnum) {
+			dev_warn(ddev, "Duplicate descriptor for config %d "
+			    "interface %d altsetting %d, skipping\n",
+			    cfgno, inum, asnum);
+			goto skip_to_next_interface_descriptor;
+		}
+	}
+
+	++intfc->num_altsetting;
+	memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
+
+	/* Skip over any Class Specific or Vendor Specific descriptors;
+	 * find the first endpoint or interface descriptor */
+	alt->extra = buffer;
+	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
+	    USB_DT_INTERFACE, &n);
+	alt->extralen = i;
+	if (n > 0)
+		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
+		    n, plural(n), "interface");
+	buffer += i;
+	size -= i;
+
+	/* Allocate space for the right(?) number of endpoints */
+	num_ep = num_ep_orig = alt->desc.bNumEndpoints;
+	alt->desc.bNumEndpoints = 0;		/* Use as a counter */
+	if (num_ep > USB_MAXENDPOINTS) {
+		dev_warn(ddev, "too many endpoints for config %d interface %d "
+		    "altsetting %d: %d, using maximum allowed: %d\n",
+		    cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
+		num_ep = USB_MAXENDPOINTS;
+	}
+
+	if (num_ep > 0) {
+		/* Can't allocate 0 bytes */
+		len = sizeof(struct usb_host_endpoint) * num_ep;
+		alt->endpoint = kzalloc(len, GFP_KERNEL);
+		if (!alt->endpoint)
+			return -ENOMEM;
+	}
+
+	/* Parse all the endpoint descriptors */
+	n = 0;
+	while (size > 0) {
+		if (((struct usb_descriptor_header *) buffer)->bDescriptorType
+		     == USB_DT_INTERFACE)
+			break;
+		retval = usb_parse_endpoint(ddev, cfgno, config, inum, asnum,
+				alt, num_ep, buffer, size);
+		if (retval < 0)
+			return retval;
+		++n;
+
+		buffer += retval;
+		size -= retval;
+	}
+
+	if (n != num_ep_orig)
+		dev_warn(ddev, "config %d interface %d altsetting %d has %d "
+		    "endpoint descriptor%s, different from the interface "
+		    "descriptor's value: %d\n",
+		    cfgno, inum, asnum, n, plural(n), num_ep_orig);
+	return buffer - buffer0;
+
+skip_to_next_interface_descriptor:
+	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
+	    USB_DT_INTERFACE, NULL);
+	return buffer - buffer0 + i;
+}
+
+static int usb_parse_configuration(struct usb_device *dev, int cfgidx,
+    struct usb_host_config *config, unsigned char *buffer, int size)
+{
+	struct device *ddev = &dev->dev;
+	unsigned char *buffer0 = buffer;
+	int cfgno;
+	int nintf, nintf_orig;
+	int i, j, n;
+	struct usb_interface_cache *intfc;
+	unsigned char *buffer2;
+	int size2;
+	struct usb_descriptor_header *header;
+	int len, retval;
+	u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
+	unsigned iad_num = 0;
+
+	memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
+	nintf = nintf_orig = config->desc.bNumInterfaces;
+	config->desc.bNumInterfaces = 0;	// Adjusted later
+
+	if (config->desc.bDescriptorType != USB_DT_CONFIG ||
+	    config->desc.bLength < USB_DT_CONFIG_SIZE ||
+	    config->desc.bLength > size) {
+		dev_err(ddev, "invalid descriptor for config index %d: "
+		    "type = 0x%X, length = %d\n", cfgidx,
+		    config->desc.bDescriptorType, config->desc.bLength);
+		return -EINVAL;
+	}
+	cfgno = config->desc.bConfigurationValue;
+
+	buffer += config->desc.bLength;
+	size -= config->desc.bLength;
+
+	if (nintf > USB_MAXINTERFACES) {
+		dev_warn(ddev, "config %d has too many interfaces: %d, "
+		    "using maximum allowed: %d\n",
+		    cfgno, nintf, USB_MAXINTERFACES);
+		nintf = USB_MAXINTERFACES;
+	}
+
+	/* Go through the descriptors, checking their length and counting the
+	 * number of altsettings for each interface */
+	n = 0;
+	for ((buffer2 = buffer, size2 = size);
+	      size2 > 0;
+	     (buffer2 += header->bLength, size2 -= header->bLength)) {
+
+		if (size2 < sizeof(struct usb_descriptor_header)) {
+			dev_warn(ddev, "config %d descriptor has %d excess "
+			    "byte%s, ignoring\n",
+			    cfgno, size2, plural(size2));
+			break;
+		}
+
+		header = (struct usb_descriptor_header *) buffer2;
+		if ((header->bLength > size2) || (header->bLength < 2)) {
+			dev_warn(ddev, "config %d has an invalid descriptor "
+			    "of length %d, skipping remainder of the config\n",
+			    cfgno, header->bLength);
+			break;
+		}
+
+		if (header->bDescriptorType == USB_DT_INTERFACE) {
+			struct usb_interface_descriptor *d;
+			int inum;
+
+			d = (struct usb_interface_descriptor *) header;
+			if (d->bLength < USB_DT_INTERFACE_SIZE) {
+				dev_warn(ddev, "config %d has an invalid "
+				    "interface descriptor of length %d, "
+				    "skipping\n", cfgno, d->bLength);
+				continue;
+			}
+
+			inum = d->bInterfaceNumber;
+
+			if ((dev->quirks & USB_QUIRK_HONOR_BNUMINTERFACES) &&
+			    n >= nintf_orig) {
+				dev_warn(ddev, "config %d has more interface "
+				    "descriptors, than it declares in "
+				    "bNumInterfaces, ignoring interface "
+				    "number: %d\n", cfgno, inum);
+				continue;
+			}
+
+			if (inum >= nintf_orig)
+				dev_warn(ddev, "config %d has an invalid "
+				    "interface number: %d but max is %d\n",
+				    cfgno, inum, nintf_orig - 1);
+
+			/* Have we already encountered this interface?
+			 * Count its altsettings */
+			for (i = 0; i < n; ++i) {
+				if (inums[i] == inum)
+					break;
+			}
+			if (i < n) {
+				if (nalts[i] < 255)
+					++nalts[i];
+			} else if (n < USB_MAXINTERFACES) {
+				inums[n] = inum;
+				nalts[n] = 1;
+				++n;
+			}
+
+		} else if (header->bDescriptorType ==
+				USB_DT_INTERFACE_ASSOCIATION) {
+			struct usb_interface_assoc_descriptor *d;
+
+			d = (struct usb_interface_assoc_descriptor *)header;
+			if (d->bLength < USB_DT_INTERFACE_ASSOCIATION_SIZE) {
+				dev_warn(ddev,
+					 "config %d has an invalid interface association descriptor of length %d, skipping\n",
+					 cfgno, d->bLength);
+				continue;
+			}
+
+			if (iad_num == USB_MAXIADS) {
+				dev_warn(ddev, "found more Interface "
+					       "Association Descriptors "
+					       "than allocated for in "
+					       "configuration %d\n", cfgno);
+			} else {
+				config->intf_assoc[iad_num] = d;
+				iad_num++;
+			}
+
+		} else if (header->bDescriptorType == USB_DT_DEVICE ||
+			    header->bDescriptorType == USB_DT_CONFIG)
+			dev_warn(ddev, "config %d contains an unexpected "
+			    "descriptor of type 0x%X, skipping\n",
+			    cfgno, header->bDescriptorType);
+
+	}	/* for ((buffer2 = buffer, size2 = size); ...) */
+	size = buffer2 - buffer;
+	config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
+
+	if (n != nintf)
+		dev_warn(ddev, "config %d has %d interface%s, different from "
+		    "the descriptor's value: %d\n",
+		    cfgno, n, plural(n), nintf_orig);
+	else if (n == 0)
+		dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
+	config->desc.bNumInterfaces = nintf = n;
+
+	/* Check for missing interface numbers */
+	for (i = 0; i < nintf; ++i) {
+		for (j = 0; j < nintf; ++j) {
+			if (inums[j] == i)
+				break;
+		}
+		if (j >= nintf)
+			dev_warn(ddev, "config %d has no interface number "
+			    "%d\n", cfgno, i);
+	}
+
+	/* Allocate the usb_interface_caches and altsetting arrays */
+	for (i = 0; i < nintf; ++i) {
+		j = nalts[i];
+		if (j > USB_MAXALTSETTING) {
+			dev_warn(ddev, "too many alternate settings for "
+			    "config %d interface %d: %d, "
+			    "using maximum allowed: %d\n",
+			    cfgno, inums[i], j, USB_MAXALTSETTING);
+			nalts[i] = j = USB_MAXALTSETTING;
+		}
+
+		len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j;
+		config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
+		if (!intfc)
+			return -ENOMEM;
+		kref_init(&intfc->ref);
+	}
+
+	/* FIXME: parse the BOS descriptor */
+
+	/* Skip over any Class Specific or Vendor Specific descriptors;
+	 * find the first interface descriptor */
+	config->extra = buffer;
+	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
+	    USB_DT_INTERFACE, &n);
+	config->extralen = i;
+	if (n > 0)
+		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
+		    n, plural(n), "configuration");
+	buffer += i;
+	size -= i;
+
+	/* Parse all the interface/altsetting descriptors */
+	while (size > 0) {
+		retval = usb_parse_interface(ddev, cfgno, config,
+		    buffer, size, inums, nalts);
+		if (retval < 0)
+			return retval;
+
+		buffer += retval;
+		size -= retval;
+	}
+
+	/* Check for missing altsettings */
+	for (i = 0; i < nintf; ++i) {
+		intfc = config->intf_cache[i];
+		for (j = 0; j < intfc->num_altsetting; ++j) {
+			for (n = 0; n < intfc->num_altsetting; ++n) {
+				if (intfc->altsetting[n].desc.
+				    bAlternateSetting == j)
+					break;
+			}
+			if (n >= intfc->num_altsetting)
+				dev_warn(ddev, "config %d interface %d has no "
+				    "altsetting %d\n", cfgno, inums[i], j);
+		}
+	}
+
+	return 0;
+}
+
+/* hub-only!! ... and only exported for reset/reinit path.
+ * otherwise used internally on disconnect/destroy path
+ */
+void usb_destroy_configuration(struct usb_device *dev)
+{
+	int c, i;
+
+	if (!dev->config)
+		return;
+
+	if (dev->rawdescriptors) {
+		for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
+			kfree(dev->rawdescriptors[i]);
+
+		kfree(dev->rawdescriptors);
+		dev->rawdescriptors = NULL;
+	}
+
+	for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
+		struct usb_host_config *cf = &dev->config[c];
+
+		kfree(cf->string);
+		for (i = 0; i < cf->desc.bNumInterfaces; i++) {
+			if (cf->intf_cache[i])
+				kref_put(&cf->intf_cache[i]->ref,
+					  usb_release_interface_cache);
+		}
+	}
+	kfree(dev->config);
+	dev->config = NULL;
+}
+
+
+/*
+ * Get the USB config descriptors, cache and parse'em
+ *
+ * hub-only!! ... and only in reset path, or usb_new_device()
+ * (used by real hubs and virtual root hubs)
+ */
+int usb_get_configuration(struct usb_device *dev)
+{
+	struct device *ddev = &dev->dev;
+	int ncfg = dev->descriptor.bNumConfigurations;
+	int result = 0;
+	unsigned int cfgno, length;
+	unsigned char *bigbuffer;
+	struct usb_config_descriptor *desc;
+
+	cfgno = 0;
+	result = -ENOMEM;
+	if (ncfg > USB_MAXCONFIG) {
+		dev_warn(ddev, "too many configurations: %d, "
+		    "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
+		dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
+	}
+
+	if (ncfg < 1) {
+		dev_err(ddev, "no configurations\n");
+		return -EINVAL;
+	}
+
+	length = ncfg * sizeof(struct usb_host_config);
+	dev->config = kzalloc(length, GFP_KERNEL);
+	if (!dev->config)
+		goto err2;
+
+	length = ncfg * sizeof(char *);
+	dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
+	if (!dev->rawdescriptors)
+		goto err2;
+
+	desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
+	if (!desc)
+		goto err2;
+
+	result = 0;
+	for (; cfgno < ncfg; cfgno++) {
+		/* We grab just the first descriptor so we know how long
+		 * the whole configuration is */
+		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
+		    desc, USB_DT_CONFIG_SIZE);
+		if (result < 0) {
+			dev_err(ddev, "unable to read config index %d "
+			    "descriptor/%s: %d\n", cfgno, "start", result);
+			if (result != -EPIPE)
+				goto err;
+			dev_err(ddev, "chopping to %d config(s)\n", cfgno);
+			dev->descriptor.bNumConfigurations = cfgno;
+			break;
+		} else if (result < 4) {
+			dev_err(ddev, "config index %d descriptor too short "
+			    "(expected %i, got %i)\n", cfgno,
+			    USB_DT_CONFIG_SIZE, result);
+			result = -EINVAL;
+			goto err;
+		}
+		length = max((int) le16_to_cpu(desc->wTotalLength),
+		    USB_DT_CONFIG_SIZE);
+
+		/* Now that we know the length, get the whole thing */
+		bigbuffer = kmalloc(length, GFP_KERNEL);
+		if (!bigbuffer) {
+			result = -ENOMEM;
+			goto err;
+		}
+
+		if (dev->quirks & USB_QUIRK_DELAY_INIT)
+			msleep(200);
+
+		result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
+		    bigbuffer, length);
+		if (result < 0) {
+			dev_err(ddev, "unable to read config index %d "
+			    "descriptor/%s\n", cfgno, "all");
+			kfree(bigbuffer);
+			goto err;
+		}
+		if (result < length) {
+			dev_warn(ddev, "config index %d descriptor too short "
+			    "(expected %i, got %i)\n", cfgno, length, result);
+			length = result;
+		}
+
+		dev->rawdescriptors[cfgno] = bigbuffer;
+
+		result = usb_parse_configuration(dev, cfgno,
+		    &dev->config[cfgno], bigbuffer, length);
+		if (result < 0) {
+			++cfgno;
+			goto err;
+		}
+	}
+	result = 0;
+
+err:
+	kfree(desc);
+	dev->descriptor.bNumConfigurations = cfgno;
+err2:
+	if (result == -ENOMEM)
+		dev_err(ddev, "out of memory\n");
+	return result;
+}
+
+void usb_release_bos_descriptor(struct usb_device *dev)
+{
+	if (dev->bos) {
+		kfree(dev->bos->desc);
+		kfree(dev->bos);
+		dev->bos = NULL;
+	}
+}
+
+static const __u8 bos_desc_len[256] = {
+	[USB_CAP_TYPE_WIRELESS_USB] = USB_DT_USB_WIRELESS_CAP_SIZE,
+	[USB_CAP_TYPE_EXT]          = USB_DT_USB_EXT_CAP_SIZE,
+	[USB_SS_CAP_TYPE]           = USB_DT_USB_SS_CAP_SIZE,
+	[USB_SSP_CAP_TYPE]          = USB_DT_USB_SSP_CAP_SIZE(1),
+	[CONTAINER_ID_TYPE]         = USB_DT_USB_SS_CONTN_ID_SIZE,
+	[USB_PTM_CAP_TYPE]          = USB_DT_USB_PTM_ID_SIZE,
+};
+
+/* Get BOS descriptor set */
+int usb_get_bos_descriptor(struct usb_device *dev)
+{
+	struct device *ddev = &dev->dev;
+	struct usb_bos_descriptor *bos;
+	struct usb_dev_cap_header *cap;
+	struct usb_ssp_cap_descriptor *ssp_cap;
+	unsigned char *buffer, *buffer0;
+	int length, total_len, num, i, ssac;
+	__u8 cap_type;
+	int ret;
+
+	bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL);
+	if (!bos)
+		return -ENOMEM;
+
+	/* Get BOS descriptor */
+	ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE);
+	if (ret < USB_DT_BOS_SIZE || bos->bLength < USB_DT_BOS_SIZE) {
+		dev_err(ddev, "unable to get BOS descriptor or descriptor too short\n");
+		if (ret >= 0)
+			ret = -ENOMSG;
+		kfree(bos);
+		return ret;
+	}
+
+	length = bos->bLength;
+	total_len = le16_to_cpu(bos->wTotalLength);
+	num = bos->bNumDeviceCaps;
+	kfree(bos);
+	if (total_len < length)
+		return -EINVAL;
+
+	dev->bos = kzalloc(sizeof(struct usb_host_bos), GFP_KERNEL);
+	if (!dev->bos)
+		return -ENOMEM;
+
+	/* Now let's get the whole BOS descriptor set */
+	buffer = kzalloc(total_len, GFP_KERNEL);
+	if (!buffer) {
+		ret = -ENOMEM;
+		goto err;
+	}
+	dev->bos->desc = (struct usb_bos_descriptor *)buffer;
+
+	ret = usb_get_descriptor(dev, USB_DT_BOS, 0, buffer, total_len);
+	if (ret < total_len) {
+		dev_err(ddev, "unable to get BOS descriptor set\n");
+		if (ret >= 0)
+			ret = -ENOMSG;
+		goto err;
+	}
+
+	buffer0 = buffer;
+	total_len -= length;
+	buffer += length;
+
+	for (i = 0; i < num; i++) {
+		cap = (struct usb_dev_cap_header *)buffer;
+
+		if (total_len < sizeof(*cap) || total_len < cap->bLength) {
+			dev->bos->desc->bNumDeviceCaps = i;
+			break;
+		}
+		cap_type = cap->bDevCapabilityType;
+		length = cap->bLength;
+		if (bos_desc_len[cap_type] && length < bos_desc_len[cap_type]) {
+			dev->bos->desc->bNumDeviceCaps = i;
+			break;
+		}
+
+		if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
+			dev_warn(ddev, "descriptor type invalid, skip\n");
+			continue;
+		}
+
+		switch (cap_type) {
+		case USB_CAP_TYPE_WIRELESS_USB:
+			/* Wireless USB cap descriptor is handled by wusb */
+			break;
+		case USB_CAP_TYPE_EXT:
+			dev->bos->ext_cap =
+				(struct usb_ext_cap_descriptor *)buffer;
+			break;
+		case USB_SS_CAP_TYPE:
+			dev->bos->ss_cap =
+				(struct usb_ss_cap_descriptor *)buffer;
+			break;
+		case USB_SSP_CAP_TYPE:
+			ssp_cap = (struct usb_ssp_cap_descriptor *)buffer;
+			ssac = (le32_to_cpu(ssp_cap->bmAttributes) &
+				USB_SSP_SUBLINK_SPEED_ATTRIBS);
+			if (length >= USB_DT_USB_SSP_CAP_SIZE(ssac))
+				dev->bos->ssp_cap = ssp_cap;
+			break;
+		case CONTAINER_ID_TYPE:
+			dev->bos->ss_id =
+				(struct usb_ss_container_id_descriptor *)buffer;
+			break;
+		case USB_PTM_CAP_TYPE:
+			dev->bos->ptm_cap =
+				(struct usb_ptm_cap_descriptor *)buffer;
+		default:
+			break;
+		}
+
+		total_len -= length;
+		buffer += length;
+	}
+	dev->bos->desc->wTotalLength = cpu_to_le16(buffer - buffer0);
+
+	return 0;
+
+err:
+	usb_release_bos_descriptor(dev);
+	return ret;
+}