This is the patch for VT6421L/VT8237A/VT8251 card supporting.

Important note:
 1. This patch is based on source files of Fedora Core 4 
 <linux-kernel-src>/drivers/scsi/sata_via.c.
 2. In the bin directory, there are two pre-compiled modules, one for SMP system,
    one for UP system.

How to apply the patch:
 1. copy the sata_via.c.patch to <linux-kernel-src>/drivers/scsi/
 2. patch  < sata_via.c.patch
 3. rebuild the modules

How to test the patched driver:
 1. After rebuilding the patched source file, we can get the module file: sata_via.ko
 2. Or we can use the pre-compiled binary files in the package.
 3. Login the running Linux system as root user.
 4. Remove the old sata_via module by using: #rmmod sata_via
 5. Install the new sata_via module by using: #insmod ./sata_via.ko
 6. Now can access the SCSI disk device /dev/sd#

What this patch does?
 1. Because VT6421 support both SATA and PATA interface, and SATA is totally
  compatible with PATA, I delete all the SATA features, make the VT6421 looks 
  like a 3 channel PATA controller.
2. For All VIA SATA Controllers, this patch addes Device ID to support them. 

