[deliverable/linux.git] / drivers / usb / core / config.c

#include <linux/usb.h>
#include <linux/usb/ch9.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <asm/byteorder.h>
#include "usb.h"
#include "hcd.h"

#define USB_MAXALTSETTING		128	/* Hard limit */
#define USB_MAXENDPOINTS		30	/* 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 int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
    int asnum, struct usb_host_interface *ifp, int num_ep,
    unsigned char *buffer, int size)
{
	unsigned char *buffer0 = buffer;
	struct usb_endpoint_descriptor *d;
	struct usb_host_endpoint *endpoint;
	int n, i, j;

	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;

	endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
	++ifp->desc.bNumEndpoints;

	memcpy(&endpoint->desc, d, n);
	INIT_LIST_HEAD(&endpoint->urb_list);

	/* If the bInterval value is outside the legal range,
	 * set it to a default value: 32 ms */
	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_HIGH:
			n = 9;		/* 32 ms = 2^(9-1) uframes */
			j = 16;
			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 = 32;
			break;
		}
	} else if (usb_endpoint_xfer_isoc(d)) {
		i = 1;
		j = 16;
		switch (to_usb_device(ddev)->speed) {
		case USB_SPEED_HIGH:
			n = 9;		/* 32 ms = 2^(9-1) uframes */
			break;
		default:		/* USB_SPEED_FULL */
			n = 6;		/* 32 ms = 2^(6-1) 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;
	}

	/* 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;
	if (n > 0)
		dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
		    n, plural(n), "endpoint");
	return buffer - buffer0 + i;

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, 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 device *ddev, int cfgidx,
    struct usb_host_config *config, unsigned char *buffer, int size)
{
	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];

	memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
	if (config->desc.bDescriptorType != USB_DT_CONFIG ||
	    config->desc.bLength < USB_DT_CONFIG_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;

	nintf = nintf_orig = config->desc.bNumInterfaces;
	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 (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_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);
	}

	/* 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;
}


// 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 = -ENOMEM;
	unsigned int cfgno, length;
	unsigned char *buffer;
	unsigned char *bigbuffer;
 	struct usb_config_descriptor *desc;

	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;

	buffer = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
	if (!buffer)
		goto err2;
	desc = (struct usb_config_descriptor *)buffer;

	for (cfgno = 0; 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,
		    buffer, USB_DT_CONFIG_SIZE);
		if (result < 0) {
			dev_err(ddev, "unable to read config index %d "
			    "descriptor/%s\n", cfgno, "start");
			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;
		}
		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->dev, cfgno,
		    &dev->config[cfgno], bigbuffer, length);
		if (result < 0) {
			++cfgno;
			goto err;
		}
	}
	result = 0;

err:
	kfree(buffer);
	dev->descriptor.bNumConfigurations = cfgno;
err2:
	if (result == -ENOMEM)
		dev_err(ddev, "out of memory\n");
	return result;
}
Commit	Line	Data
1da177e4	1	#include <linux/usb.h>
615ae11b	2	#include <linux/usb/ch9.h>
1da177e4 LT	3	#include <linux/module.h>
	4	#include <linux/init.h>
	5	#include <linux/slab.h>
	6	#include <linux/device.h>
	7	#include <asm/byteorder.h>
6d5e8254 GK	8	#include "usb.h"
6d5e8254 GK	9	#include "hcd.h"
1da177e4 LT	10
	11	#define USB_MAXALTSETTING 128 /* Hard limit */
	12	#define USB_MAXENDPOINTS 30 /* Hard limit */
	13
	14	#define USB_MAXCONFIG 8 /* Arbitrary limit */
	15
	16
	17	static inline const char *plural(int n)
	18	{
	19	return (n == 1 ? "" : "s");
	20	}
	21
	22	static int find_next_descriptor(unsigned char *buffer, int size,
	23	int dt1, int dt2, int *num_skipped)
	24	{
	25	struct usb_descriptor_header *h;
	26	int n = 0;
	27	unsigned char *buffer0 = buffer;
	28
	29	/* Find the next descriptor of type dt1 or dt2 */
	30	while (size > 0) {
	31	h = (struct usb_descriptor_header *) buffer;
	32	if (h->bDescriptorType == dt1 \|\| h->bDescriptorType == dt2)
	33	break;
	34	buffer += h->bLength;
	35	size -= h->bLength;
	36	++n;
	37	}
	38
	39	/* Store the number of descriptors skipped and return the
	40	* number of bytes skipped */
	41	if (num_skipped)
	42	*num_skipped = n;
	43	return buffer - buffer0;
	44	}
	45
	46	static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum,
	47	int asnum, struct usb_host_interface *ifp, int num_ep,
	48	unsigned char *buffer, int size)
	49	{
	50	unsigned char *buffer0 = buffer;
	51	struct usb_endpoint_descriptor *d;
	52	struct usb_host_endpoint *endpoint;
615ae11b	53	int n, i, j;
1da177e4 LT	54
	55	d = (struct usb_endpoint_descriptor *) buffer;
	56	buffer += d->bLength;
	57	size -= d->bLength;
	58
	59	if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE)
	60	n = USB_DT_ENDPOINT_AUDIO_SIZE;
	61	else if (d->bLength >= USB_DT_ENDPOINT_SIZE)
	62	n = USB_DT_ENDPOINT_SIZE;
	63	else {
	64	dev_warn(ddev, "config %d interface %d altsetting %d has an "
	65	"invalid endpoint descriptor of length %d, skipping\n",
	66	cfgno, inum, asnum, d->bLength);
	67	goto skip_to_next_endpoint_or_interface_descriptor;
	68	}
	69
	70	i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK;
	71	if (i >= 16 \|\| i == 0) {
	72	dev_warn(ddev, "config %d interface %d altsetting %d has an "
	73	"invalid endpoint with address 0x%X, skipping\n",
	74	cfgno, inum, asnum, d->bEndpointAddress);
	75	goto skip_to_next_endpoint_or_interface_descriptor;
	76	}
	77
	78	/* Only store as many endpoints as we have room for */
	79	if (ifp->desc.bNumEndpoints >= num_ep)
	80	goto skip_to_next_endpoint_or_interface_descriptor;
	81
	82	endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints];
	83	++ifp->desc.bNumEndpoints;
	84
	85	memcpy(&endpoint->desc, d, n);
	86	INIT_LIST_HEAD(&endpoint->urb_list);
	87
615ae11b AS	88	/* If the bInterval value is outside the legal range,
	89	* set it to a default value: 32 ms */
	90	i = 0; /* i = min, j = max, n = default */
	91	j = 255;
	92	if (usb_endpoint_xfer_int(d)) {
	93	i = 1;
	94	switch (to_usb_device(ddev)->speed) {
	95	case USB_SPEED_HIGH:
	96	n = 9; /* 32 ms = 2^(9-1) uframes */
	97	j = 16;
	98	break;
	99	default: /* USB_SPEED_FULL or _LOW */
	100	/* For low-speed, 10 ms is the official minimum.
	101	* But some "overclocked" devices might want faster
	102	* polling so we'll allow it. */
	103	n = 32;
	104	break;
	105	}
	106	} else if (usb_endpoint_xfer_isoc(d)) {
	107	i = 1;
	108	j = 16;
	109	switch (to_usb_device(ddev)->speed) {
	110	case USB_SPEED_HIGH:
	111	n = 9; /* 32 ms = 2^(9-1) uframes */
	112	break;
	113	default: /* USB_SPEED_FULL */
	114	n = 6; /* 32 ms = 2^(6-1) frames */
	115	break;
	116	}
	117	}
	118	if (d->bInterval < i \|\| d->bInterval > j) {
	119	dev_warn(ddev, "config %d interface %d altsetting %d "
	120	"endpoint 0x%X has an invalid bInterval %d, "
	121	"changing to %d\n",
	122	cfgno, inum, asnum,
	123	d->bEndpointAddress, d->bInterval, n);
	124	endpoint->desc.bInterval = n;
	125	}
	126
1da177e4 LT	127	/* Skip over any Class Specific or Vendor Specific descriptors;
	128	* find the next endpoint or interface descriptor */
	129	endpoint->extra = buffer;
	130	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
	131	USB_DT_INTERFACE, &n);
	132	endpoint->extralen = i;
	133	if (n > 0)
	134	dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
	135	n, plural(n), "endpoint");
	136	return buffer - buffer0 + i;
	137
	138	skip_to_next_endpoint_or_interface_descriptor:
	139	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
	140	USB_DT_INTERFACE, NULL);
	141	return buffer - buffer0 + i;
	142	}
	143
	144	void usb_release_interface_cache(struct kref *ref)
	145	{
	146	struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref);
	147	int j;
	148
4f62efe6 AS	149	for (j = 0; j < intfc->num_altsetting; j++) {
	150	struct usb_host_interface *alt = &intfc->altsetting[j];
	151
	152	kfree(alt->endpoint);
	153	kfree(alt->string);
	154	}
1da177e4 LT	155	kfree(intfc);
	156	}
	157
	158	static int usb_parse_interface(struct device *ddev, int cfgno,
	159	struct usb_host_config config, unsigned char buffer, int size,
	160	u8 inums[], u8 nalts[])
	161	{
	162	unsigned char *buffer0 = buffer;
	163	struct usb_interface_descriptor *d;
	164	int inum, asnum;
	165	struct usb_interface_cache *intfc;
	166	struct usb_host_interface *alt;
	167	int i, n;
	168	int len, retval;
	169	int num_ep, num_ep_orig;
	170
	171	d = (struct usb_interface_descriptor *) buffer;
	172	buffer += d->bLength;
	173	size -= d->bLength;
	174
	175	if (d->bLength < USB_DT_INTERFACE_SIZE)
	176	goto skip_to_next_interface_descriptor;
	177
	178	/* Which interface entry is this? */
	179	intfc = NULL;
	180	inum = d->bInterfaceNumber;
	181	for (i = 0; i < config->desc.bNumInterfaces; ++i) {
	182	if (inums[i] == inum) {
	183	intfc = config->intf_cache[i];
	184	break;
	185	}
	186	}
	187	if (!intfc \|\| intfc->num_altsetting >= nalts[i])
	188	goto skip_to_next_interface_descriptor;
	189
	190	/* Check for duplicate altsetting entries */
	191	asnum = d->bAlternateSetting;
	192	for ((i = 0, alt = &intfc->altsetting[0]);
	193	i < intfc->num_altsetting;
	194	(++i, ++alt)) {
	195	if (alt->desc.bAlternateSetting == asnum) {
	196	dev_warn(ddev, "Duplicate descriptor for config %d "
	197	"interface %d altsetting %d, skipping\n",
	198	cfgno, inum, asnum);
	199	goto skip_to_next_interface_descriptor;
	200	}
	201	}
	202
	203	++intfc->num_altsetting;
	204	memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE);
	205
	206	/* Skip over any Class Specific or Vendor Specific descriptors;
	207	* find the first endpoint or interface descriptor */
	208	alt->extra = buffer;
	209	i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT,
	210	USB_DT_INTERFACE, &n);
	211	alt->extralen = i;
	212	if (n > 0)
	213	dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
	214	n, plural(n), "interface");
	215	buffer += i;
	216	size -= i;
	217
	218	/* Allocate space for the right(?) number of endpoints */
219	num_ep = num_ep_orig = alt->desc.bNumEndpoints;
220	alt->desc.bNumEndpoints = 0; // Use as a counter
221	if (num_ep > USB_MAXENDPOINTS) {
222	dev_warn(ddev, "too many endpoints for config %d interface %d "
223	"altsetting %d: %d, using maximum allowed: %d\n",
224	cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS);
225	num_ep = USB_MAXENDPOINTS;
226	}
227
57a21c1b AS	228	if (num_ep > 0) { /* Can't allocate 0 bytes */
	229	len = sizeof(struct usb_host_endpoint) * num_ep;
	230	alt->endpoint = kzalloc(len, GFP_KERNEL);
	231	if (!alt->endpoint)
	232	return -ENOMEM;
	233	}
1da177e4 LT	234
	235	/* Parse all the endpoint descriptors */
	236	n = 0;
	237	while (size > 0) {
	238	if (((struct usb_descriptor_header *) buffer)->bDescriptorType
	239	== USB_DT_INTERFACE)
	240	break;
	241	retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt,
	242	num_ep, buffer, size);
	243	if (retval < 0)
	244	return retval;
	245	++n;
	246
	247	buffer += retval;
	248	size -= retval;
	249	}
	250
	251	if (n != num_ep_orig)
	252	dev_warn(ddev, "config %d interface %d altsetting %d has %d "
	253	"endpoint descriptor%s, different from the interface "
	254	"descriptor's value: %d\n",
	255	cfgno, inum, asnum, n, plural(n), num_ep_orig);
	256	return buffer - buffer0;
	257
	258	skip_to_next_interface_descriptor:
	259	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
	260	USB_DT_INTERFACE, NULL);
	261	return buffer - buffer0 + i;
	262	}
	263
	264	static int usb_parse_configuration(struct device *ddev, int cfgidx,
	265	struct usb_host_config config, unsigned char buffer, int size)
	266	{
	267	unsigned char *buffer0 = buffer;
	268	int cfgno;
	269	int nintf, nintf_orig;
	270	int i, j, n;
	271	struct usb_interface_cache *intfc;
	272	unsigned char *buffer2;
	273	int size2;
	274	struct usb_descriptor_header *header;
	275	int len, retval;
	276	u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES];
	277
	278	memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE);
	279	if (config->desc.bDescriptorType != USB_DT_CONFIG \|\|
	280	config->desc.bLength < USB_DT_CONFIG_SIZE) {
	281	dev_err(ddev, "invalid descriptor for config index %d: "
	282	"type = 0x%X, length = %d\n", cfgidx,
	283	config->desc.bDescriptorType, config->desc.bLength);
	284	return -EINVAL;
	285	}
	286	cfgno = config->desc.bConfigurationValue;
	287
	288	buffer += config->desc.bLength;
	289	size -= config->desc.bLength;
	290
	291	nintf = nintf_orig = config->desc.bNumInterfaces;
	292	if (nintf > USB_MAXINTERFACES) {
	293	dev_warn(ddev, "config %d has too many interfaces: %d, "
	294	"using maximum allowed: %d\n",
	295	cfgno, nintf, USB_MAXINTERFACES);
	296	nintf = USB_MAXINTERFACES;
	297	}
298
299	/* Go through the descriptors, checking their length and counting the
300	* number of altsettings for each interface */
301	n = 0;
302	for ((buffer2 = buffer, size2 = size);
303	size2 > 0;
304	(buffer2 += header->bLength, size2 -= header->bLength)) {
305
306	if (size2 < sizeof(struct usb_descriptor_header)) {
307	dev_warn(ddev, "config %d descriptor has %d excess "
308	"byte%s, ignoring\n",
309	cfgno, size2, plural(size2));
310	break;
311	}
312
313	header = (struct usb_descriptor_header *) buffer2;
314	if ((header->bLength > size2) \|\| (header->bLength < 2)) {
315	dev_warn(ddev, "config %d has an invalid descriptor "
316	"of length %d, skipping remainder of the config\n",
317	cfgno, header->bLength);
318	break;
319	}
320
321	if (header->bDescriptorType == USB_DT_INTERFACE) {
322	struct usb_interface_descriptor *d;
323	int inum;
324
325	d = (struct usb_interface_descriptor *) header;
326	if (d->bLength < USB_DT_INTERFACE_SIZE) {
327	dev_warn(ddev, "config %d has an invalid "
328	"interface descriptor of length %d, "
329	"skipping\n", cfgno, d->bLength);
330	continue;
331	}
332
333	inum = d->bInterfaceNumber;
334	if (inum >= nintf_orig)
335	dev_warn(ddev, "config %d has an invalid "
336	"interface number: %d but max is %d\n",
337	cfgno, inum, nintf_orig - 1);
338
339	/* Have we already encountered this interface?
340	* Count its altsettings */
341	for (i = 0; i < n; ++i) {
342	if (inums[i] == inum)
343	break;
344	}
345	if (i < n) {
346	if (nalts[i] < 255)
347	++nalts[i];
348	} else if (n < USB_MAXINTERFACES) {
349	inums[n] = inum;
350	nalts[n] = 1;
351	++n;
352	}
353
354	} else if (header->bDescriptorType == USB_DT_DEVICE \|\|
355	header->bDescriptorType == USB_DT_CONFIG)
356	dev_warn(ddev, "config %d contains an unexpected "
357	"descriptor of type 0x%X, skipping\n",
358	cfgno, header->bDescriptorType);
359
360	} /* for ((buffer2 = buffer, size2 = size); ...) */
361	size = buffer2 - buffer;
362	config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0);
363
364	if (n != nintf)
365	dev_warn(ddev, "config %d has %d interface%s, different from "
366	"the descriptor's value: %d\n",
367	cfgno, n, plural(n), nintf_orig);
368	else if (n == 0)
369	dev_warn(ddev, "config %d has no interfaces?\n", cfgno);
370	config->desc.bNumInterfaces = nintf = n;
371
372	/* Check for missing interface numbers */
373	for (i = 0; i < nintf; ++i) {
374	for (j = 0; j < nintf; ++j) {
375	if (inums[j] == i)
376	break;
377	}
378	if (j >= nintf)
379	dev_warn(ddev, "config %d has no interface number "
380	"%d\n", cfgno, i);
381	}
382
383	/* Allocate the usb_interface_caches and altsetting arrays */
384	for (i = 0; i < nintf; ++i) {
385	j = nalts[i];
386	if (j > USB_MAXALTSETTING) {
387	dev_warn(ddev, "too many alternate settings for "
388	"config %d interface %d: %d, "
389	"using maximum allowed: %d\n",
390	cfgno, inums[i], j, USB_MAXALTSETTING);
391	nalts[i] = j = USB_MAXALTSETTING;
392	}
393
394	len = sizeof(intfc) + sizeof(struct usb_host_interface) j;
0a1ef3b5	395	config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL);
1da177e4 LT	396	if (!intfc)
1da177e4 LT	397	return -ENOMEM;
1da177e4 LT	398	kref_init(&intfc->ref);
	399	}
	400
	401	/* Skip over any Class Specific or Vendor Specific descriptors;
	402	* find the first interface descriptor */
	403	config->extra = buffer;
	404	i = find_next_descriptor(buffer, size, USB_DT_INTERFACE,
	405	USB_DT_INTERFACE, &n);
	406	config->extralen = i;
	407	if (n > 0)
	408	dev_dbg(ddev, "skipped %d descriptor%s after %s\n",
	409	n, plural(n), "configuration");
	410	buffer += i;
	411	size -= i;
	412
	413	/* Parse all the interface/altsetting descriptors */
	414	while (size > 0) {
	415	retval = usb_parse_interface(ddev, cfgno, config,
	416	buffer, size, inums, nalts);
	417	if (retval < 0)
	418	return retval;
	419
	420	buffer += retval;
	421	size -= retval;
	422	}
	423
	424	/* Check for missing altsettings */
	425	for (i = 0; i < nintf; ++i) {
	426	intfc = config->intf_cache[i];
	427	for (j = 0; j < intfc->num_altsetting; ++j) {
	428	for (n = 0; n < intfc->num_altsetting; ++n) {
	429	if (intfc->altsetting[n].desc.
	430	bAlternateSetting == j)
	431	break;
	432	}
	433	if (n >= intfc->num_altsetting)
	434	dev_warn(ddev, "config %d interface %d has no "
	435	"altsetting %d\n", cfgno, inums[i], j);
	436	}
	437	}
	438
	439	return 0;
	440	}
	441
	442	// hub-only!! ... and only exported for reset/reinit path.
	443	// otherwise used internally on disconnect/destroy path
	444	void usb_destroy_configuration(struct usb_device *dev)
	445	{
	446	int c, i;
	447
	448	if (!dev->config)
	449	return;
	450
	451	if (dev->rawdescriptors) {
	452	for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
	453	kfree(dev->rawdescriptors[i]);
	454
	455	kfree(dev->rawdescriptors);
	456	dev->rawdescriptors = NULL;
	457	}
	458
	459	for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
	460	struct usb_host_config *cf = &dev->config[c];
	461
462	kfree(cf->string);
1da177e4 LT	463	for (i = 0; i < cf->desc.bNumInterfaces; i++) {
	464	if (cf->intf_cache[i])
	465	kref_put(&cf->intf_cache[i]->ref,
	466	usb_release_interface_cache);
	467	}
	468	}
	469	kfree(dev->config);
	470	dev->config = NULL;
	471	}
	472
	473
	474	// hub-only!! ... and only in reset path, or usb_new_device()
	475	// (used by real hubs and virtual root hubs)
	476	int usb_get_configuration(struct usb_device *dev)
	477	{
	478	struct device *ddev = &dev->dev;
	479	int ncfg = dev->descriptor.bNumConfigurations;
	480	int result = -ENOMEM;
	481	unsigned int cfgno, length;
	482	unsigned char *buffer;
	483	unsigned char *bigbuffer;
	484	struct usb_config_descriptor *desc;
	485
	486	if (ncfg > USB_MAXCONFIG) {
	487	dev_warn(ddev, "too many configurations: %d, "
	488	"using maximum allowed: %d\n", ncfg, USB_MAXCONFIG);
	489	dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG;
	490	}
	491
	492	if (ncfg < 1) {
	493	dev_err(ddev, "no configurations\n");
	494	return -EINVAL;
	495	}
	496
	497	length = ncfg * sizeof(struct usb_host_config);
0a1ef3b5	498	dev->config = kzalloc(length, GFP_KERNEL);
1da177e4 LT	499	if (!dev->config)
1da177e4 LT	500	goto err2;
1da177e4 LT	501
1da177e4 LT	502	length = ncfg * sizeof(char *);
0a1ef3b5	503	dev->rawdescriptors = kzalloc(length, GFP_KERNEL);
1da177e4 LT	504	if (!dev->rawdescriptors)
1da177e4 LT	505	goto err2;
1da177e4 LT	506
	507	buffer = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL);
	508	if (!buffer)
	509	goto err2;
	510	desc = (struct usb_config_descriptor *)buffer;
	511
	512	for (cfgno = 0; cfgno < ncfg; cfgno++) {
	513	/* We grab just the first descriptor so we know how long
	514	* the whole configuration is */
	515	result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
	516	buffer, USB_DT_CONFIG_SIZE);
	517	if (result < 0) {
	518	dev_err(ddev, "unable to read config index %d "
	519	"descriptor/%s\n", cfgno, "start");
cb4c8fe5 IPG	520	dev_err(ddev, "chopping to %d config(s)\n", cfgno);
	521	dev->descriptor.bNumConfigurations = cfgno;
	522	break;
1da177e4 LT	523	} else if (result < 4) {
	524	dev_err(ddev, "config index %d descriptor too short "
	525	"(expected %i, got %i)\n", cfgno,
	526	USB_DT_CONFIG_SIZE, result);
	527	result = -EINVAL;
	528	goto err;
	529	}
	530	length = max((int) le16_to_cpu(desc->wTotalLength),
	531	USB_DT_CONFIG_SIZE);
	532
	533	/* Now that we know the length, get the whole thing */
	534	bigbuffer = kmalloc(length, GFP_KERNEL);
	535	if (!bigbuffer) {
	536	result = -ENOMEM;
	537	goto err;
	538	}
	539	result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno,
	540	bigbuffer, length);
	541	if (result < 0) {
	542	dev_err(ddev, "unable to read config index %d "
	543	"descriptor/%s\n", cfgno, "all");
	544	kfree(bigbuffer);
	545	goto err;
	546	}
	547	if (result < length) {
	548	dev_warn(ddev, "config index %d descriptor too short "
	549	"(expected %i, got %i)\n", cfgno, length, result);
	550	length = result;
	551	}
	552
	553	dev->rawdescriptors[cfgno] = bigbuffer;
	554
	555	result = usb_parse_configuration(&dev->dev, cfgno,
	556	&dev->config[cfgno], bigbuffer, length);
	557	if (result < 0) {
	558	++cfgno;
	559	goto err;
	560	}
	561	}
	562	result = 0;
	563
	564	err:
	565	kfree(buffer);
	566	dev->descriptor.bNumConfigurations = cfgno;
	567	err2:
	568	if (result == -ENOMEM)
	569	dev_err(ddev, "out of memory\n");
	570	return result;
	571	}