kernel params for OTG Host?

hi!

I have bult a kernel with buildroot and linux-omap3 kernel
(v2.6.37_OMAPPSP_04.02.00.07) and the usb otg port ist not working as
host. I have attached a hub with an A cable (pin 4 and 5 shorted) and
an ftdi rs232 adapter. which kernel config parameters are necessary?
For example the TWL4030 USB transceiver driver seems to be necessary.
Is there a list or howto?

-Jochen

Now it basically works with this config
USB support
            EHCI HCD (usb 2.0) support
            Inventra highspeed dual role controller
                OMAP2430 and onwards

            USB serial converter support
                USB FTDI single port serial driver
            off: USB gadget support
            TWL4030 USB transceiver driver

Now the next problem is that the communication does not work with the
rs232 ftdi adapter even though the kernel reports
[ 757.443786] ftdi_sio 1-1.3:1.0: FTDI USB Serial Device converter
detected
[ 757.451812] usb 1-1.3: Detected FT232BM
[ 757.455963] usb 1-1.3: Number of endpoints 2
[ 757.460418] usb 1-1.3: Endpoint 1 MaxPacketSize 64
[ 757.465484] usb 1-1.3: Endpoint 2 MaxPacketSize 64
[ 757.470520] usb 1-1.3: Setting MaxPacketSize 64
[ 757.476806] usb 1-1.3: FTDI USB Serial Device converter now
attached to ttyUSB0
[ 757.485626] drivers/usb/core/inode.c: creating file '004'
[ 757.491546] hub 1-1:1.0: state 7 ports 4 chg 0000 evt 0008