经测试一张USB 300M的WIFI网卡是USB2.0的 ,但是插入210的板上识别时尝试了4次high speed都失败了,最后使用的是full speed,这个full speed就是USB 1.1啊
[root@FriendlyARM /mnt]#
[ 503.017419] usb 1-1: new high speed USB device using s5p-ehci and address 6 /***第1次尝试high speed***/
[ 503.138539] usb 1-1: device descriptor read/64, error -71
[ 503.365141] usb 1-1: device descriptor read/64, error -71
[ 503.579982] usb 1-1: new high speed USB device using s5p-ehci and address 7 /***第2次尝试high speed***/
[ 503.701024] usb 1-1: device descriptor read/64, error -71
[ 503.927615] usb 1-1: device descriptor read/64, error -71
[ 504.142455] usb 1-1: new high speed USB device using s5p-ehci and address 8 /***第3次尝试high speed***/
[ 504.564323] usb 1-1: device not accepting address 8, error -71
[ 504.673645] usb 1-1: new high speed USB device using s5p-ehci and address 9 /***第4次尝试high speed***/
[ 505.095585] usb 1-1: device not accepting address 9, error -71
[ 505.095659] hub 1-0:1.0: unable to enumerate USB device on port 1
[ 505.482302] usb 2-1: new full speed USB device using s5p-ohci and address 3 /***使用full speed , ohci***/
[ 505.629722] usb 2-1: not running at top speed; connect to a high speed hub
[ 505.641739] usb 2-1: New USB device found, idVendor=0bda, idProduct=8178
[ 505.641798] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 505.641859] usb 2-1: Product: 802.11n WLAN Adapter
[ 505.641902] usb 2-1: Manufacturer: Realtek
[ 505.642099] usb 2-1: SerialNumber: 00e04c000001
[ 505.650917] register rtw_netdev_ops to netdev_ops
[ 505.651291] CHIP TYPE: RTL8188C_8192C
不知道为何high speed会出现 error -71,在内核查到该错误如下:
#define EPROTO 71 /* Protocol error */
-EPROTO (*, **) a) bitstuff error
b) no response packet received within the
prescribed bus turn-around time
c) unknown USB error