Is it possible to do some Inquiry requests to SCSI driver?
No it is not possible from userland.
By design, Mac OS X does not allow applications to send SCSI or ATA commands to storage devices unless the application developer also provides an in-kernel device driver that supports the commands. The SCSI Architecture Model family allows only one logical unit driver to control a device at a time and provides in-kernel logical unit drivers for storage devices (as listed in “SCSI Architecture Model Family Device Support”). Similarly, the ATA family does not allow applications to send ATA commands directly to ATA or SATA (Serial ATA) devices.