Linux USB maxpower command and outputs

Sat Jan 02 11:35:53 craiga>lsusb -v |grep 'Bus\|MaxPower'

Bus 001 Device 002: ID 0a5c:bd11 Broadcom Corp. TiVo AG0100 802.11bg Wireless Adapter [Broadcom BCM4320]
      (Bus Powered)
    MaxPower              200mA

Bus 001 Device 002: ID 7392:7811 Edimax Technology Co., Ltd EW-7811Un 802.11n Wireless Adapter [Realtek RTL8188CUS]

      (Bus Powered)

    MaxPower              500mA

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

    MaxPower                0mA