Commit 89dc2905 authored by Matthew Wilcox's avatar Matthew Wilcox Committed by Greg Kroah-Hartman
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USB: uas: Ensure we only bind to a UAS interface 



While all existing UAS devices use alternate interface 1, this is not
guaranteed, and it has caused confusion with people trying to bind the
uas driver to non-uas devices.

Signed-off-by: default avatarMatthew Wilcox <willy@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 92a3f767

drivers/usb/storage/uas.c

+30 −7
Original line number Diff line number Diff line
@@ -582,6 +582,34 @@ static struct usb_device_id uas_usb_ids[] = { 
};

MODULE_DEVICE_TABLE(usb, uas_usb_ids);



static int uas_is_interface(struct usb_host_interface *intf)

{

	return (intf->desc.bInterfaceClass == USB_CLASS_MASS_STORAGE &&

		intf->desc.bInterfaceSubClass == USB_SC_SCSI &&

		intf->desc.bInterfaceProtocol == USB_PR_UAS);

}



static int uas_switch_interface(struct usb_device *udev,

						struct usb_interface *intf)

{

	int i;



	if (uas_is_interface(intf->cur_altsetting))

		return 0;



	for (i = 0; i < intf->num_altsetting; i++) {

		struct usb_host_interface *alt = &intf->altsetting[i];

		if (alt == intf->cur_altsetting)

			continue;

		if (uas_is_interface(alt))

			return usb_set_interface(udev,

						alt->desc.bInterfaceNumber,

						alt->desc.bAlternateSetting);

	}



	return -ENODEV;

}



static void uas_configure_endpoints(struct uas_dev_info *devinfo)

{

	struct usb_host_endpoint *eps[4] = { };
@@ -655,13 +683,8 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id) 
	struct uas_dev_info *devinfo;

	struct usb_device *udev = interface_to_usbdev(intf);



	if (id->bInterfaceProtocol == 0x50) {

		int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;

/* XXX: Shouldn't assume that 1 is the alternative we want */

		int ret = usb_set_interface(udev, ifnum, 1);

		if (ret)

	if (uas_switch_interface(udev, intf))

		return -ENODEV;

	}



	devinfo = kmalloc(sizeof(struct uas_dev_info), GFP_KERNEL);

	if (!devinfo)