Index: uspace/lib/usb/include/usb/devdrv.h
===================================================================
--- uspace/lib/usb/include/usb/devdrv.h	(revision 9bc276bc317bd87d4320847c42015b0aced099d4)
+++ uspace/lib/usb/include/usb/devdrv.h	(revision 7526e3d9dbfa6a43fb1014e632caa2fbe206bd0b)
@@ -47,4 +47,27 @@
 } usb_device_descriptors_t;
 
+/** Wrapper for data related to alternate interface setting.
+ * The pointers will typically point inside configuration descriptor and
+ * thus you shall not deallocate them.
+ */
+typedef struct {
+	/** Interface descriptor. */
+	usb_standard_interface_descriptor_t *interface;
+	/** Pointer to start of descriptor tree bound with this interface. */
+	uint8_t *nested_descriptors;
+	/** Size of data pointed by nested_descriptors in bytes. */
+	size_t nested_descriptors_size;
+} usb_alternate_interface_descriptors_t;
+
+/** Alternate interface settings. */
+typedef struct {
+	/** Array of alternate interfaces descriptions. */
+	usb_alternate_interface_descriptors_t *alternatives;
+	/** Size of @c alternatives array. */
+	size_t alternative_count;
+	/** Index of currently selected one. */
+	size_t current;
+} usb_alternate_interfaces_t;
+
 /** USB device structure. */
 typedef struct {
@@ -61,4 +84,10 @@
 	 */
 	int interface_no;
+
+	/** Alternative interfaces.
+	 * Set to NULL when the driver controls whole device
+	 * (i.e. more (or any) interfaces).
+	 */
+	usb_alternate_interfaces_t *alternate_interfaces;
 
 	/** Some useful descriptors. */
@@ -132,5 +161,4 @@
 typedef void (*usb_polling_terminted_callback_t)(usb_device_t *, bool, void *);
 
-
 int usb_device_auto_poll(usb_device_t *, size_t,
     usb_polling_callback_t, size_t, usb_polling_terminted_callback_t, void *);