mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-25 11:37:56 +00:00
185 lines
5.2 KiB
Groff
185 lines
5.2 KiB
Groff
.Dd August 27, 1993
|
|
.Dt CD 4
|
|
.Os FreeBSD
|
|
.Sh NAME
|
|
.Nm cd
|
|
.Nd scsi cdrom driver
|
|
.Sh SYNOPSIS
|
|
.Nm device cd
|
|
.Nm device cd1 target 4 lun 0
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Xr cd
|
|
driver provides support for a
|
|
.Em scsi
|
|
cdrom. It allows the cdrom
|
|
to be divided up into a set of pseudo devices called
|
|
.Em partitions.
|
|
In an attempt to look like regular disks the
|
|
.Nm
|
|
driver synthesises a partition table, with one partition covering the entire
|
|
cdrom. A user might (for some amazing reason) add another partition to the
|
|
cdrom by using disklabel, but it will last only until the cdrom is unmounted.
|
|
A Partition can have both a
|
|
.Em raw
|
|
interface
|
|
and a
|
|
.Em Block mode
|
|
interface.
|
|
In general the interfaces are similar to those described by
|
|
.Xr wd 4
|
|
or
|
|
.Xr sd 4 .
|
|
|
|
.Pp
|
|
Where the
|
|
.Xr wd 4
|
|
device has a fairly low level interface to the system,
|
|
.Em SCSI
|
|
devices have a much higher level interface and talk to the system via
|
|
a
|
|
.Em SCSI Adapter
|
|
and a
|
|
.Em Scsi Adapter driver
|
|
e.g.
|
|
.Xr AHA1542 .
|
|
A scsi adapter must also be separatly configured into the system
|
|
before a scsi cdrom can be configured.
|
|
.Pp
|
|
As the scsi adapter is probed during boot, the
|
|
.Em SCSI
|
|
bus is scanned for devices. Any devices found which answer as 'Readonly'
|
|
type devices will be 'attached' to the
|
|
.Nm
|
|
driver.
|
|
In FreeBSD releases prior to 2.1, the first found will be attached as
|
|
.Em cd0
|
|
and the next,
|
|
.Em cd1
|
|
etc.
|
|
Beginning in 2.1 it is possible to specify what cd unit a device should
|
|
come on line as; refer to
|
|
.Xr scsi 4
|
|
for details on kernel configuration.
|
|
.Pp
|
|
The system utility
|
|
.Xr disklabel 1
|
|
may be used to read the synthesized
|
|
.Xr disklabel 5
|
|
structure, which will contain correct figures for the size of the cdrom
|
|
should that information be required.
|
|
.Pp
|
|
.Sh KERNEL CONFIGURATION
|
|
Any number of cdroms may be attached to the system regardless of system
|
|
configuration as all resources are dynamically allocated.
|
|
|
|
.Pp
|
|
.Sh IOCTLS
|
|
The following
|
|
.Xr ioctl 2
|
|
calls apply to scsi cdroms
|
|
in the header files
|
|
.Em sys/cdio.h.
|
|
and
|
|
.Em sys/disklabel.h
|
|
|
|
.Bl -tag -width CDIOCPLAYAUDIO____
|
|
|
|
.It Dv DIOCGDINFO
|
|
Read, from the kernel, the in-core copy of the disklabel for the
|
|
drive. This will be a ficticious disklabel it will contain information
|
|
read from the scsi inquiry commands, and should be the same as
|
|
the information printed at boot.
|
|
.It Dv DIOCSDINFO
|
|
Give the driver a new disklabel to use. The driver will NOT try write the new
|
|
disklabel to the disk. (ok?)
|
|
.It CDIOCPLAYTRACKS
|
|
Start Audio playback given a track address and length.
|
|
.It CDIOCPLAYBLOCKS
|
|
Start Audio playback given a block address and length.
|
|
.It CDIOCPLAYMSF
|
|
Start Audio playback given a 'Minutes/ seconds/ frames' address and length.
|
|
.It CDIOCREADSUBCHANNEL
|
|
Read information from the subchannel at the location specified.
|
|
.It CDIOREADTOCHEADER
|
|
Return summary information about the table of contents for the mounted cdrom.
|
|
.It CDIOREADTOCENTRYS
|
|
Return information from the table of contents entries mentionned.
|
|
.It CDIOCSETPATCH
|
|
Attach various audio channels to various output channels.
|
|
.It CDIOCGETVOL
|
|
Get information about the volume settings of the output channels.
|
|
.It CDIOCSETVOL
|
|
Change the volume settings of the output channels.
|
|
.It CDIOCSETMONO
|
|
Patch all out[put channels to all source channels.
|
|
.It CDIOCSETSTERIO
|
|
Patch left source channel to the left output channel and the right
|
|
source channel to the right output channel.
|
|
.It CDIOCSETMUTE
|
|
Mute output without changing the volume settings.
|
|
.It CDIOCSETLEFT
|
|
Attach both output channels to the left source channel.
|
|
.It CDIOCSETRIGHT
|
|
Attach both output channels to the right source channel.
|
|
.It CDIOCSETDEBUG
|
|
Turn on debugging for the appropriate device.
|
|
.It CDIOCCLRDEBUG
|
|
Turn off debugging for the appropriate device.
|
|
.It CDIOCPAUSE
|
|
Pause audio play, do not reset the location of the read-head.
|
|
.It CDIOCRESUME
|
|
Resume audio play, Start at the location of the pause.
|
|
.It CDIOCRESET
|
|
Reset the drive.
|
|
.It CDIOCSTART
|
|
Tell the drive to spin-up the cdrom.
|
|
.It CDIOCSTOP
|
|
Tell the drive to spin-down the cdrom.
|
|
.It CDIOCEJECT
|
|
Eject the cdrom.
|
|
.El
|
|
.Pp
|
|
In addition the general
|
|
.Xr scsi 4
|
|
ioctls may be used with the
|
|
.Nm
|
|
driver, if used against the fourth (raw/whole disk) partiton. (e.g. rcd0d)
|
|
.Sh NOTES
|
|
When a cdrom is changed in a drive controlled by the
|
|
.Nm
|
|
driver, then the act of changing the media will invalidate the
|
|
disklabel and information held within the kernel. To stop corruption,
|
|
All accesses to the device will be discarded until there are no more
|
|
open file descriptors referencing the device. During this period, all
|
|
new open attempts will be rejected. When No more open file descriptors
|
|
reference the device, the first next open will load a new set of
|
|
figures (including disklabel) for the drive.
|
|
|
|
The Audio code in the
|
|
.Nm
|
|
driver only support SCSI2 standard audio commands. As there are many cdrom
|
|
manufacturers who have not followed the standard well, there are many
|
|
cdroms for which audio will not work. Some work is planned to support
|
|
some of the more common 'broken' cdrom drives however this is not yet
|
|
under way.
|
|
|
|
.Sh FILES
|
|
.Bl -tag -width /dev/rcd[0-9][a-h] -compact
|
|
.It Pa /dev/cd[0-9][a-h]
|
|
block mode scsi disks
|
|
.It Pa /dev/rcd[0-9][a-h]
|
|
raw scsi disks
|
|
.El
|
|
.Sh DIAGNOSTICS
|
|
None.
|
|
.Sh SEE ALSO
|
|
.Xr disklabel 1
|
|
.Xr disklabel 5
|
|
.Xr wd 4
|
|
.Xr sd 4
|
|
.Sh HISTORY
|
|
This
|
|
.Nm
|
|
driver appeared in 386BSD 0.1.
|