I have got it.
So, i wanted to use an Android phone to access web by wi-imx28.
First, building Kernel i should had RDNIS_host driver AND cdc_ethernet AND usbnet.
On the wiimx28 module, launch "modprobe rndis_host";
when i connect the phone in modem mode, usb0 appears in "ifconfig -a".
I should configure in "/etc/network/interfaces" usb0 port to dhcp.
AND That's all, wiimx28 googling !
Xavier DAVID BEAULIEU, Saint-Emilion, France