DragonFly On-Line Manual Pages

Search: Section:  

CD(9)                 DragonFly Kernel Developer's Manual                CD(9)


NAME

     cd -- CDROM driver for the CAM SCSI subsystem


DESCRIPTION

     The cd device driver provides a read only interface for CDROM drives
     (SCSI type 5) and WORM drives (SCSI type 4) that support CDROM type com-
     mands.  Some drives don't behave as the driver expects.  See the section
     QUIRKS for info on possible flags.


QUIRKS

     Each CD-ROM device can have different interpretations of the SCSI spec.
     This can lead to drives requiring special handling in the driver.  The
     following is a list of quirks that the driver recognize.

     CD_Q_NO_TOUCH    This flag tell the driver not to probe the drive at
                      attach time to see if there is a disk in the drive and
                      find out what size it is.  This flag is currently unim-
                      plemented in the CAM cd driver.

     CD_Q_BCD_TRACKS  This flag is for broken drives that return the track
                      numbers in packed BCD instead of straight decimal.  If
                      the drive seems to skip tracks (tracks 10-15 are
                      skipped) then you have a drive that is in need of this
                      flag.

     CD_Q_NO_CHANGER  This flag tells the driver that the device in question
                      is not a changer.  This is only necessary for a CDROM
                      device with multiple luns that are not a part of a
                      changer.

     CD_Q_CHANGER     This flag tells the driver that the given device is a
                      multi-lun changer.  In general, the driver will figure
                      this out automatically when it sees a LUN greater than
                      0.  Setting this flag only has the effect of telling the
                      driver to run the initial read capacity command for LUN
                      0 of the changer through the changer scheduling code.


FILES

     /sys/bus/cam/scsi/scsi_cd.c  is the driver source file.


SEE ALSO

     cd(4), scsi(4)


HISTORY

     The cd manual page first appeared in FreeBSD 2.2.


AUTHORS

     This manual page was written by John-Mark Gurney <gurney_j@efn.org>.  It
     was updated for CAM and FreeBSD 3.0 by Kenneth Merry <ken@FreeBSD.org>.

DragonFly 3.5                  October 10, 1998                  DragonFly 3.5

Search: Section: