diff options
Diffstat (limited to 'drivers/usb/core/message.c')
| -rw-r--r-- | drivers/usb/core/message.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 4c143231471..530e854961c 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -1384,6 +1384,36 @@ struct device_type usb_if_device_type = { .uevent = usb_if_uevent, }; +static struct usb_interface_assoc_descriptor *find_iad(struct usb_device *dev, + struct usb_host_config *config, + u8 inum) +{ + struct usb_interface_assoc_descriptor *retval = NULL; + struct usb_interface_assoc_descriptor *intf_assoc; + int first_intf; + int last_intf; + int i; + + for (i = 0; (i < USB_MAXIADS && config->intf_assoc[i]); i++) { + intf_assoc = config->intf_assoc[i]; + if (intf_assoc->bInterfaceCount == 0) + continue; + + first_intf = intf_assoc->bFirstInterface; + last_intf = first_intf + (intf_assoc->bInterfaceCount - 1); + if (inum >= first_intf && inum <= last_intf) { + if (!retval) + retval = intf_assoc; + else + dev_err(&dev->dev, "Interface #%d referenced" + " by multiple IADs\n", inum); + } + } + + return retval; +} + + /* * usb_set_configuration - Makes a particular device setting be current * @dev: the device whose configuration is being updated @@ -1530,6 +1560,7 @@ free_interfaces: intfc = cp->intf_cache[i]; intf->altsetting = intfc->altsetting; intf->num_altsetting = intfc->num_altsetting; + intf->intf_assoc = find_iad(dev, cp, i); kref_get(&intfc->ref); alt = usb_altnum_to_altsetting(intf, 0); |