i was able to enumerate a flash drive in my computer but failed to install driver for a device called "cdc serial". i had ran out its physical serial ports.
the g_acm_ms modules simply don't work, not matter what parameter i gave:
modprobe g_acm_ms file=/dev/mmcblk0p1
[ 4340.710601] usb_composite_probe
[ 4340.713958] usb_gadget_probe_driver
[ 4340.717620] usb_gadget_probe_driver
[ 4340.726318] gadget: Mass Storage Function, version: 2009/09/11
[ 4340.732543] gadget: Number of LUNs=1
[ 4340.736389] lun0: LUN: removable file: /dev/mmcblk0p1
[ 4340.741973] gadget: Composite Gadget (ACM + MS), version: 2011/10/10
[ 4340.748718] gadget: g_acm_ms ready
[ 4340.757263] g_acm_ms musb-hdrc.0: failed to start *** g_acm_ms: -22
modprobe: 'kernel/drivers/usb/gadget/g_acm_ms.ko': invalid parameter
so this g_multi module is my saver, please help with the driver issue.