diff options
Diffstat (limited to 'sys/dev/usb2/core/usb2_parse.c')
| -rw-r--r-- | sys/dev/usb2/core/usb2_parse.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/sys/dev/usb2/core/usb2_parse.c b/sys/dev/usb2/core/usb2_parse.c new file mode 100644 index 000000000000..223b3c2634da --- /dev/null +++ b/sys/dev/usb2/core/usb2_parse.c @@ -0,0 +1,208 @@ +/* $FreeBSD$ */ +/*- + * Copyright (c) 2008 Hans Petter Selasky. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <dev/usb2/include/usb2_standard.h> +#include <dev/usb2/include/usb2_mfunc.h> + +#include <dev/usb2/core/usb2_core.h> +#include <dev/usb2/core/usb2_parse.h> + +/*------------------------------------------------------------------------* + * usb2_desc_foreach + * + * This function is the safe way to iterate across the USB config + * descriptor. It contains several checks against invalid + * descriptors. If the "desc" argument passed to this function is + * "NULL" the first descriptor, if any, will be returned. + * + * Return values: + * NULL: End of descriptors + * Else: Next descriptor after "desc" + *------------------------------------------------------------------------*/ +struct usb2_descriptor * +usb2_desc_foreach(struct usb2_config_descriptor *cd, struct usb2_descriptor *desc) +{ + void *end; + + if (cd == NULL) { + return (NULL); + } + end = USB_ADD_BYTES(cd, UGETW(cd->wTotalLength)); + + if (desc == NULL) { + desc = USB_ADD_BYTES(cd, 0); + } else { + desc = USB_ADD_BYTES(desc, desc->bLength); + } + return (((((void *)desc) >= ((void *)cd)) && + (((void *)desc) < end) && + (USB_ADD_BYTES(desc, desc->bLength) >= ((void *)cd)) && + (USB_ADD_BYTES(desc, desc->bLength) <= end) && + (desc->bLength >= sizeof(*desc))) ? desc : NULL); +} + +/*------------------------------------------------------------------------* + * usb2_find_idesc + * + * This function will return the interface descriptor, if any, that + * has index "iface_index" and alternate index "alt_index". + * + * Return values: + * NULL: End of descriptors + * Else: A valid interface descriptor + *------------------------------------------------------------------------*/ +struct usb2_interface_descriptor * +usb2_find_idesc(struct usb2_config_descriptor *cd, + uint8_t iface_index, uint8_t alt_index) +{ + struct usb2_descriptor *desc = NULL; + struct usb2_interface_descriptor *id; + uint8_t curidx = 0; + uint8_t lastidx = 0; + uint8_t curaidx = 0; + uint8_t first = 1; + + while ((desc = usb2_desc_foreach(cd, desc))) { + if ((desc->bDescriptorType == UDESC_INTERFACE) && + (desc->bLength >= sizeof(*id))) { + id = (void *)desc; + + if (first) { + first = 0; + lastidx = id->bInterfaceNumber; + + } else if (id->bInterfaceNumber != lastidx) { + + lastidx = id->bInterfaceNumber; + curidx++; + curaidx = 0; + + } else { + curaidx++; + } + + if ((iface_index == curidx) && (alt_index == curaidx)) { + return (id); + } + } + } + return (NULL); +} + +/*------------------------------------------------------------------------* + * usb2_find_edesc + * + * This function will return the endpoint descriptor for the passed + * interface index, alternate index and endpoint index. + * + * Return values: + * NULL: End of descriptors + * Else: A valid endpoint descriptor + *------------------------------------------------------------------------*/ +struct usb2_endpoint_descriptor * +usb2_find_edesc(struct usb2_config_descriptor *cd, + uint8_t iface_index, uint8_t alt_index, uint8_t ep_index) +{ + struct usb2_descriptor *desc = NULL; + struct usb2_interface_descriptor *d; + uint8_t curidx = 0; + + d = usb2_find_idesc(cd, iface_index, alt_index); + if (d == NULL) + return (NULL); + + if (ep_index >= d->bNumEndpoints) /* quick exit */ + return (NULL); + + desc = ((void *)d); + + while ((desc = usb2_desc_foreach(cd, desc))) { + + if (desc->bDescriptorType == UDESC_INTERFACE) { + break; + } + if (desc->bDescriptorType == UDESC_ENDPOINT) { + if (curidx == ep_index) { + if (desc->bLength < + sizeof(struct usb2_endpoint_descriptor)) { + /* endpoint index is invalid */ + break; + } + return ((void *)desc); + } + curidx++; + } + } + return (NULL); +} + +/*------------------------------------------------------------------------* + * usb2_get_no_endpoints + * + * This function will count the total number of endpoints available. + *------------------------------------------------------------------------*/ +uint16_t +usb2_get_no_endpoints(struct usb2_config_descriptor *cd) +{ + struct usb2_descriptor *desc = NULL; + uint16_t count = 0; + + while ((desc = usb2_desc_foreach(cd, desc))) { + if (desc->bDescriptorType == UDESC_ENDPOINT) { + count++; + } + } + return (count); +} + +/*------------------------------------------------------------------------* + * usb2_get_no_alts + * + * Return value: + * Number of alternate settings for the given "ifaceno". + * + * NOTE: The returned can be larger than the actual number of + * alternate settings. + *------------------------------------------------------------------------*/ +uint16_t +usb2_get_no_alts(struct usb2_config_descriptor *cd, uint8_t ifaceno) +{ + struct usb2_descriptor *desc = NULL; + struct usb2_interface_descriptor *id; + uint16_t n = 0; + + while ((desc = usb2_desc_foreach(cd, desc))) { + + if ((desc->bDescriptorType == UDESC_INTERFACE) && + (desc->bLength >= sizeof(*id))) { + id = (void *)desc; + if (id->bInterfaceNumber == ifaceno) { + n++; + } + } + } + return (n); +} |