kern/103602: drive gets wedged on READ CD CAPACITY if no disc is in

Thomas Quinot thomas at FreeBSD.ORG
Tue Mar 13 22:01:30 UTC 2007


* Scott Long, 2007-03-13 :

> >I'm confused.  CAM actually sends a READ_CAPACITY command to the drive, 
> >not a READ_CD_CAPACITY command.  Are you saying that issuing both a
> >READ_CAPACITY and a READ_CD_CAPACITY to an empty Sony drive results in
> >the same bad behavior?

Er, now *I* am confused. As I understand it, READ CAPACITY and READ CD
RECORDED CAPACITY both refer to the same opcode (0x25), READ CAPACITY
being the SBC terminology, while READ CD RECORDED CAPACITY is the MMC
terminology.

> Actually, I take that back, adding a TUR phase isn't as hard as I
> thought.  I'd like to know if doing a READ_CD_CAPACITY makes a
> difference, though.

Josh can probably test some commands and report the results, if you send
him some camcontrol cmd's to experiment with.

Thomas.



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