Error in syslog on 2.6.20

[William Thompson <wt@electro-mechanical.com>]

I'm not on either list, keep me in CC.

I noticed the following error on a cdrom device:
ata2.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 frozen
ata2.00: cmd a0/00:00:00:00:20/00:00:00:00:00/a0 tag 0 cdb 0x0 data 0
         res 40/00:03:00:00:00/00:00:00:00:00/a0 Emask 0x4 (timeout)
ata2: soft resetting port
ata2.00: configured for MWDMA2
ata2: EH complete

This is the device when it was found:
libata version 2.00 loaded.
ata_piix 0000:00:1f.1: version 2.00ac7
ata1: PATA max UDMA/100 cmd 0x1F0 ctl 0x3F6 bmdma 0xFFA0 irq 14
ata2: PATA max UDMA/100 cmd 0x170 ctl 0x376 bmdma 0xFFA8 irq 15
scsi0 : ata_piix
ata1.00: ATA-4, max UDMA/66, 16514064 sectors: LBA
ata1.00: ata1: dev 0 multi count 8
ata1.00: configured for UDMA/66
scsi1 : ata_piix
ata2.00: ATAPI, max MWDMA2
ata2.00: configured for MWDMA2
scsi 0:0:0:0: Direct-Access     ATA      WDC WD84AA       05.0 PQ: 0 ANSI: 5
scsi 1:0:0:0: CD-ROM            LITEON   CD-ROM LTN486S   YQSM PQ: 0 ANSI: 5

I have a program that does a scsi TEST UNIT READY on many devices once every
.1 second.  The problem occured when I ejected the cdrom and closed the tray
again with valid media in the drive.  My program noticed media removed and
inserted, then said the device was dead/unpollable.  This is when I saw this
error.