ata_pio_devchk9
Pata device presence detection
Usage
unsigned int ata_pio_devchk(struct ata_port * ap, unsigned int device);
Arguments
ap
ATA channel to examine
device
Device to examine (starting at zero)
Overview
This technique was originally described in Hale Landis's ATADRVR (www.ata-atapi.com), and later found its way into the ATA/ATAPI spec.
Write a pattern to the ATA shadow registers, and if a device is present, it will respond by correctly storing and echoing back the ATA shadow register contents.
Locking
caller.