I'm running Ubuntu 12.04 / 3.2.0-1412-omap2 on a PandaBoard ES rev B2 and I am attempting to use the PandaBoard between a Win7 PC (connected to the OTG port) and a Western Digital My Passport HDD (connected to one of the host USB ports). Yes, this is one of those wonderful full-disk, self-encrypting devices (insert eye roll here). I have attempted to use the USB Mass Storage gadget driver (g_mass_storage) to some success: the WD comes up in Ubuntu as /dev/sr0 (because that is the read-only unlocker partition, defined as a CD-ROM device) AND the Win7 machine does see the WD unlocker partition, too, but I am unable to communicate with the device. It appears that the WD device is expecting an IOCTL_SCSI_PASS_THROUGH_DIRECT command to unlock it; it also appears that the command is dropped or ignored by the gadget driver.

Using a *standard* WD HDD, I can read & write through the PandaBoard without any problems using the above method. As stated above, though, it appear it is that one command that seems to ignored completely. I have attempted to implement g_serial, g_zero, as well as several other modules to no avail; g_mass_storage is the closest.

I'm still fairly new to Linux, although everything I've read states that this *should* work... and it does not. Any thoughts or suggestions would be greatly appreciated.

Thank you!!!

Allow me to clarify a bit: the goal is to work around Windows' and WD's quasi-non-standard USB implementation. Instead of using the mass storage gadget, is there any way to make the PandaBoard appear to Windows as a "generic USB hub" instead of as "Linux CD-Gadget", thus making the Pandaboard essentially transparent in the communications chain? Is there a USB gadget driver that strictly implements a soft hub, thus linking the OTG port and one of the USB host ports?

Again, thank you!