Using the Neo as an USB Mass storage device
Make the Neo FreeRunner act as a mass storage device
To access the microSD card in the Freerunner from the host computer as if it were a USB key or memory stick, the following script can be used:
#!/bin/sh ifdown usb0 umount /media/card rmmod g_ether modprobe g_file_storage file=/dev/mmcblk0 stall=0
Reference: Petr Vanek's "usb mass media storage" message on the community mailing list, updated by Mmontour 16:25, 21 March 2009 (UTC). The "stall=0" parameter is required on at least some systems to prevent timeouts and errors.
The card is not accessible from the Freerunner in this mode. Sometimes, however, the message displayed may be "interface usb0 already configured" and no device would be detected by the OS FreeRunner is connected to.
Make the Neo FreeRunner revert to USB networking
The following script can be used:
#!/bin/sh rmmod g_file_storage mount /dev/mmcblk0p1 /media/card modprobe g_ether ifup usb0
Be sure to properly unmount on the host computer first, just as you would with any other USB storage.
Is it possible to pretend to be a USB hub, providing both g_ether and g_file_storage?
Not yet. At the moment it's one gadget driver at a time, but there is a project under way to allow use of multiple gadget drivers together. See this blog posting called 'USB Composite Gadget Framework' or Linux-USB Gadget API Framework