Tribblix: manual page: cdio.4i

CDIO(4I) Ioctl Requests CDIO(4I)

NAME

cdio - CD-ROM control operations

SYNOPSIS

#include <sys/cdio.h>

DESCRIPTION

The set of ioctl(2) commands described below are used to perform audio
and CD-ROM specific operations. Basic to these cdio ioctl requests are
the definitions in <sys/cdio.h>.

Several CD-ROM specific commands can report addresses either in LBA
(Logical Block Address) format or in MSF (Minute, Second, Frame)
format. The READ HEADER, BREAD SUBCHANNEL, and BREAD TABLE OF CONTENTS
commands have this feature.

LBA format represents the logical block address for the CD-ROM absolute
address field or for the offset from the beginning of the current track
expressed as a number of logical blocks in a CD-ROM track relative
address field. MSF format represents the physical address written on
CD-ROM discs, expressed as a sector count relative to either the
beginning of the medium or the beginning of the current track.

IOCTLS

The following I/O controls do not have any additional data passed into
or received from them.

CDROMSTART This ioctl(2) spins up the disc and seeks to the last
address requested.

CDROMSTOP This ioctl(2) spins down the disc.

CDROMPAUSE This ioctl(2) pauses the current audio play operation.

CDROMRESUME This ioctl(2) resumes the paused audio play operation.

CDROMEJECT This ioctl(2) ejects the caddy with the disc.

CDROMCLOSETRAY This ioctl(2) closes the caddy with the disc.

The following I/O controls require a pointer to the structure for that
ioctl(2), with data being passed into the ioctl(2).

CDROMPLAYMSF This ioctl(2) command requests the drive to output the
audio signals at the specified starting address and
continue the audio play until the specified ending
address is detected. The address is in MSF format.
The third argument of this ioctl(2) call is a pointer
to the type struct cdrom_msf.

/*
* definition of play audio msf structure
*/
struct cdrom_msf {
/* starting minute */
unsigned char cdmsf_min0;
/* starting second */
unsigned char cdmsf_sec0;
/* starting frame */
unsigned char cdmsf_frame0;
/* ending minute */
unsigned char cdmsf_min1;
/* ending second */
unsigned char cdmsf_sec1;
/* ending frame */
unsigned char cdmsf_frame1;
};

The CDROMREADTOCENTRY ioctl request may be used to
obtain the start time for a track. An approximation
of the finish time can be obtained by using the
CDROMREADTOCENTRY ioctl request to retrieve the start
time of the track following the current track.

The leadout track is the next consecutive track after
the last audio track. Hence, the start time of the
leadout track may be used as the effective finish time
of the last audio track.

CDROMPLAYTRKIND This ioctl(2) command is similar to CDROMPLAYMSF. The
starting and ending address is in track/index format.
The third argument of the ioctl(2) call is a pointer
to the type struct cdrom_ti.

/*
* definition of play audio track/index structure
*/
struct cdrom_ti {
/* starting track */
unsigned char cdti_trk0;
/* starting index */
unsigned char cdti_ind0;
/* ending track */
unsigned char cdti_trk1;
/* ending index */
unsigned char cdti_ind1;
};

CDROMVOLCTRL This ioctl(2) command controls the audio output level.
The SCSI command allows the control of up to four
channels. The current implementation of the supported
CD-ROM drive only uses channel 0 and channel 1. The
valid values of volume control are between 0x00 and
0xFF, with a value of 0xFF indicating maximum volume.
The third argument of the ioctl(2) call is a pointer
to struct cdrom_volctrl which contains the output
volume values.

/*
* definition of audio volume control structure
*/
struct cdrom_volctrl {
unsigned char channel0;
unsigned char channel1;
unsigned char channel2;
unsigned char channel3;
};

The following I/O controls take a pointer that will have data returned
to the user program from the CD-ROM driver.

CDROMREADTOCHDR This ioctl(2) command returns the header of the table
of contents (TOC). The header consists of the
starting track number and the ending track number of
the disc. These two numbers are returned through a
pointer of struct cdrom_tochdr. While the disc can
start at any number, all tracks between the first and
last tracks are in contiguous ascending order.

/*
* definition of read toc header structure
*/
struct cdrom_tochdr {
unsigned char cdth_trk0; /* starting track */
unsigned char cdth_trk1; /* ending track */
};

CDROMREADTOCENTRY
This ioctl(2) command returns the information of a
specified track. The third argument of the function
call is a pointer to the type struct cdrom_tocentry.
The caller needs to supply the track number and the
address format. This command will return a 4-bit adr
field, a 4-bit ctrl field, the starting address in MSF
format or LBA format, and the data mode if the track
is a data track. The ctrl field specifies whether the
track is data or audio.

/*
* definition of read toc entry structure
*/
struct cdrom_tocentry {
unsigned char cdte_track;
unsigned char cdte_adr :4;
unsigned char cdte_ctrl :4;
unsigned char cdte_format;
union {
struct {
unsigned char minute;
unsigned char second;
unsigned char frame;
} msf;
int lba;
} cdte_addr;
unsigned char cdte_datamode;
};

To get the information from the leadout track, the
following value is appropriate for the cdte_track
field:

CDROM_LEADOUT Leadout track

To get the information from the data track, the
following value is appropriate for the cdte_ctrl
field:

CDROM_DATA_TRACK Data track

The following values are appropriate for the
cdte_format field:

CDROM_LBA LBA format

CDROM_MSF MSF format

CDROMSUBCHNL This ioctl(2) command reads the Q sub-channel data of
the current block. The subchannel data includes track
number, index number, absolute CD-ROM address, track
relative CD-ROM address, control data and audio
status. All information is returned through a pointer
to struct cdrom_subchnl. The caller needs to supply
the address format for the returned address.

struct cdrom_subchnl {
unsigned char cdsc_format;
unsigned char cdsc_audiostatus;
unsigned char cdsc_adr :4;
unsigned char cdsc_ctrl :4;
unsigned char cdsc_trk;
unsigned char cdsc_ind;
union {
struct {
unsigned char minute;
unsigned char second;
unsigned char frame;
} msf;
int lba;
} cdsc_absaddr;
union {
struct {
unsigned char minute;
unsigned char second;
unsigned char frame;
} msf;
int lba;
} cdsc_reladdr;
};

The following values are valid for the audio status
field returned from READ SUBCHANNEL command:

CDROM_AUDIO_INVALID Audio status not supported.

CDROM_AUDIO_PLAY Audio play operation in
progress.

CDROM_AUDIO_PAUSED Audio play operation paused.

CDROM_AUDIO_COMPLETED Audio play successfully
completed.

CDROM_AUDIO_ERROR Audio play stopped due to
error.

CDROM_AUDIO_NO_STATUS No current audio status to
return.

CDROMREADOFFSET This ioctl(2) command returns the absolute CD-ROM
address of the first track in the last session of a
Multi-Session CD-ROM. The third argument of the
ioctl(2) call is a pointer to an int.

CDROMCDDA This ioctl(2) command returns the CD-DA data or the
subcode data. The third argument of the ioctl(2) call
is a pointer to the type struct cdrom_cdda. In
addition to allocating memory and supplying its
address, the caller needs to supply the starting
address of the data, the transfer length in terms of
the number of blocks to be transferred, and the
subcode options. The caller also needs to issue the
CDROMREADTOCENTRY ioctl(2) to find out which tracks
contain CD-DA data before issuing this ioctl(2).

/*
* Definition of CD-DA structure
*/
struct cdrom_cdda {
unsigned int cdda_addr;
unsigned int cdda_length;
caddr_t cdda_data;
unsigned char cdda_subcode;
};

cdda_addr signifies the starting logical block
address. cdda_length signifies the transfer length in
blocks. The length of the block depends on the
cdda_subcode selection, which is explained below. To
get the subcode information related to CD-DA data, the
following values are appropriate for the cdda_subcode
field:

CDROM_DA_NO_SUBCODE CD-DA data with no subcode.

CDROM_DA_SUBQ CD-DA data with sub Q code.

CDROM_DA_ALL_SUBCODE CD-DA data with all subcode.

CDROM_DA_SUBCODE_ONLY All subcode only.

To allocate the memory related to CD-DA and/or subcode
data, the following values are appropriate for each
data block transferred:

CD-DA data with no subcode 2352 bytes

CD-DA data with sub Q code 2368 bytes

CD-DA data with all subcode 2448 bytes

All subcode only 96 bytes

CDROMCDXA This ioctl(2) command returns the CD-ROM XA (CD-ROM
Extended Architecture) data according to CD-ROM XA
format. The third argument of the ioctl(2) call is a
pointer to the type struct cdrom_cdxa. In addition to
allocating memory and supplying its address, the
caller needs to supply the starting address of the
data, the transfer length in terms of number of
blocks, and the format. The caller also needs to
issue the CDROMREADTOCENTRY ioctl(2) to find out which
tracks contain CD-ROM XA data before issuing this
ioctl(2).

/*
* Definition of CD-ROM XA structure
*/
struct cdrom_cdxa {
unsigned int cdxa_addr;
unsigned int cdxa_length;
caddr_t cdxa_data;
unsigned char cdxa_format;
};

To get the proper CD-ROM XA data, the following values
are appropriate for the cdxa_format field:

CDROM_XA_DATA CD-ROM XA data only

CDROM_XA_SECTOR_DATA CD-ROM XA all sector data

CDROM_XA_DATA_W_ERROR CD-ROM XA data with error flags
data

To allocate the memory related to CD-ROM XA format,
the following values are appropriate for each data
block transferred:

CD-ROM XA data only 2048 bytes

CD-ROM XA all sector data 2352 bytes

CD-ROM XA data with error flags data 2646 bytes

CDROMSUBCODE This ioctl(2) command returns raw subcode data
(subcodes P ~ W are described in the "Red Book," see
SEE ALSO) to the initiator while the target is playing
audio. The third argument of the ioctl(2) call is a
pointer to the type struct cdrom_subcode. The caller
needs to supply the transfer length in terms of number
of blocks and allocate memory for subcode data. The
memory allocated should be a multiple of 96 bytes
depending on the transfer length.

/*
* Definition of subcode structure
*/
struct cdrom_subcode {
unsigned int cdsc_length;
caddr_t cdsc_addr;
};

The next group of I/O controls get and set various CD-ROM drive
parameters.

CDROMGBLKMODE This ioctl(2) command returns the current block size
used by the CD-ROM drive. The third argument of the
ioctl(2) call is a pointer to an integer.

CDROMSBLKMODE This ioctl(2) command requests the CD-ROM drive to
change from the current block size to the requested
block size. The third argument of the ioctl(2) call is
an integer which contains the requested block size.
This ioctl(2) command operates in exclusive-use mode
only. The caller must ensure that no other processes
can operate on the same CD-ROM device before issuing
this ioctl(2). read(2) behavior subsequent to this
ioctl(2) remains the same: the caller is still
constrained to read the raw device on block boundaries
and in block multiples. To set the proper block size,
the following values are appropriate:

CDROM_BLK_512 512 bytes

CDROM_BLK_1024 1024 bytes

CDROM_BLK_2048 2048 bytes

CDROM_BLK_2056 2056 bytes

CDROM_BLK_2336 2336 bytes

CDROM_BLK_2340 2340 bytes

CDROM_BLK_2352 2352 bytes

CDROM_BLK_2368 2368 bytes

CDROM_BLK_2448 2448 bytes

CDROM_BLK_2646 2646 bytes

CDROM_BLK_2647 2647 bytes

CDROMGDRVSPEED This ioctl(2) command returns the current CD-ROM drive
speed. The third argument of the ioctl(2) call is a
pointer to an integer.

CDROMSDRVSPEED This ioctl(2) command requests the CD-ROM drive to
change the current drive speed to the requested drive
speed. This speed setting is only applicable when
reading data areas. The third argument of the ioctl(2)
is an integer which contains the requested drive speed.
To set the CD-ROM drive to the proper speed, the
following values are appropriate:

CDROM_NORMAL_SPEED 150k/second

CDROM_DOUBLE_SPEED 300k/second

CDROM_QUAD_SPEED 600k/second

CDROM_MAXIMUM_SPEED 300k/second (2x drive)

600k/second (4x drive)

Note that these numbers are only accurate when reading
2048 byte blocks. The CD-ROM drive will automatically
switch to normal speed when playing audio tracks and
will switch back to the speed setting when accessing
data.

ARCHITECTURE

All

INTERFACE STABILITY

Uncommitted

NOTES

The CDROMCDDA, CDROMCDXA, CDROMSUBCODE, CDROMGDRVSPEED, CDROMSDRVSPEED,
and some of the block sizes in CDROMSBLKMODE are designed for new Sun-
supported CD-ROM drives and might not work on some of the older CD-ROM
drives.

CDROMCDDA, CDROMCDXA, and CDROMSUBCODE will return error if the
transfer length exceeds valid limits as determined appropriate.
Example: for MMC-2 drives, length can not exceed 3 bytes (i.e.
0xffffff). The same restriction is enforced for older, pre-MMC-2
drives, as no limit was published for these older drives (and 3 bytes
is reasonable for all media). Note that enforcing this limit does not
imply that values passed in below this limit will actually be
applicable for each and every piece of media.

The interface to this device is preliminary and subject to change in
future releases. Programs should be written in a modular fashion so
that future changes can be easily incorporated.

illumos October 22, 2017 illumos