Index: uspace/drv/usbhub/ports.c
===================================================================
--- uspace/drv/usbhub/ports.c	(revision c50941fd0b3723a4ed5ea15d4ac8d4816bf4ab93)
+++ uspace/drv/usbhub/ports.c	(revision c156c2d0df49edf3338754d987f9771ce6097be4)
@@ -40,4 +40,11 @@
 #include <usb/debug.h>
 
+/** Retrieve port status.
+ *
+ * @param[in] ctrl_pipe Control pipe to use.
+ * @param[in] port Port number (starting at 1).
+ * @param[out] status Where to store the port status.
+ * @return Error code.
+ */
 static int get_port_status(usb_pipe_t *ctrl_pipe, size_t port,
     usb_port_status_t *status)
@@ -66,4 +73,5 @@
 }
 
+/** Information for fibril for device discovery. */
 struct add_device_phase1 {
 	usb_hub_info_t *hub;
@@ -72,4 +80,13 @@
 };
 
+/** Callback for enabling a specific port.
+ *
+ * We wait on a CV until port is reseted.
+ * That is announced via change on interrupt pipe.
+ *
+ * @param port_no Port number (starting at 1).
+ * @param arg Custom argument, points to @c usb_hub_info_t.
+ * @return Error code.
+ */
 static int enable_port_callback(int port_no, void *arg)
 {
@@ -108,4 +125,12 @@
 }
 
+/** Fibril for adding a new device.
+ *
+ * Separate fibril is needed because the port reset completion is announced
+ * via interrupt pipe and thus we cannot block here.
+ *
+ * @param arg Pointer to struct add_device_phase1.
+ * @return 0 Always.
+ */
 static int add_device_phase1_worker_fibril(void *arg)
 {
@@ -142,4 +167,13 @@
 }
 
+/** Start device adding when connection change is detected.
+ *
+ * This fires a new fibril to complete the device addition.
+ *
+ * @param hub Hub where the change occured.
+ * @param port Port index (starting at 1).
+ * @param speed Speed of the device.
+ * @return Error code.
+ */
 static int add_device_phase1_new_fibril(usb_hub_info_t *hub, size_t port,
     usb_speed_t speed)
@@ -179,4 +213,9 @@
 }
 
+/** Process change on a single port.
+ *
+ * @param hub Hub to which the port belongs.
+ * @param port Port index (starting at 1).
+ */
 static void process_port_change(usb_hub_info_t *hub, size_t port)
 {
@@ -252,4 +291,13 @@
 }
 
+
+/** Callback for polling hub for port changes.
+ *
+ * @param dev Device where the change occured.
+ * @param change_bitmap Bitmap of changed ports.
+ * @param change_bitmap_size Size of the bitmap in bytes.
+ * @param arg Custom argument, points to @c usb_hub_info_t.
+ * @return Whether to continue polling.
+ */
 bool hub_port_changes_callback(usb_device_t *dev,
     uint8_t *change_bitmap, size_t change_bitmap_size, void *arg)
Index: uspace/drv/usbhub/ports.h
===================================================================
--- uspace/drv/usbhub/ports.h	(revision c50941fd0b3723a4ed5ea15d4ac8d4816bf4ab93)
+++ uspace/drv/usbhub/ports.h	(revision c156c2d0df49edf3338754d987f9771ce6097be4)
@@ -46,11 +46,23 @@
 #include <usb/devdrv.h>
 
+/** Information about single port on a hub. */
 typedef struct {
+	/** Mutex needed by CV for checking port reset. */
 	fibril_mutex_t reset_mutex;
+	/** CV for waiting to port reset completion. */
 	fibril_condvar_t reset_cv;
+	/** Whether port reset is completed.
+	 * Guarded by @c reset_mutex.
+	 */
+	bool reset_completed;
+
+	/** Information about attached device. */
 	usb_hc_attached_device_t attached_device;
-	bool reset_completed;
 } usb_hub_port_t;
 
+/** Initialize hub port information.
+ *
+ * @param port Port to be initialized.
+ */
 static inline void usb_hub_port_init(usb_hub_port_t *port) {
 	port->attached_device.address = -1;