cdrom.txt

linux 内核源代码

CDROM_GET_UPC			CDROM_GET_MCN  (deprecated)

	Not implemented, as of 2.6.8.1



CDROMRESET			hard-reset the drive

	usage:

	  ioctl(fd, CDROMRESET, 0);

	inputs:		none

	outputs:	none

	error return:
	  EACCES	Access denied:  requires CAP_SYS_ADMIN
	  ENOSYS	Drive is not capable of resetting.




CDROMREADCOOKED			read data in cooked mode

	usage:

	  u8 buffer[CD_FRAMESIZE]
	  ioctl(fd, CDROMREADCOOKED, buffer);

	inputs:		none

	outputs:
	  2048 bytes of data, "cooked" mode.

	notes:
	  Not implemented on all drives.




CDROMREADALL			read all 2646 bytes

	Same as CDROMREADCOOKED, but reads 2646 bytes.



CDROMSEEK			seek msf address

	usage:

	  struct cdrom_msf msf;
	  ioctl(fd, CDROMSEEK, &msf);

	inputs:
	  MSF address to seek to.

	outputs:	none



CDROMPLAYBLK			scsi-cd only, (struct cdrom_blk)

	usage:

	  struct cdrom_blk blk;
	  ioctl(fd, CDROMPLAYBLK, &blk);

	inputs:
	  Region to play

	outputs:	none



CDROMGETSPINDOWN

	usage:

	  char spindown;
	  ioctl(fd, CDROMGETSPINDOWN, &spindown);

	inputs:		none

	outputs:
	  The value of the current 4-bit spindown value.




CDROMSETSPINDOWN

	usage:

	  char spindown
	  ioctl(fd, CDROMSETSPINDOWN, &spindown);

	inputs:
	  4-bit value used to control spindown (TODO: more detail here)

	outputs:	none





CDROM_SET_OPTIONS		Set behavior options

	usage:

	  int options;
	  ioctl(fd, CDROM_SET_OPTIONS, options);

	inputs:
	  New values for drive options.  The logical 'or' of:
	    CDO_AUTO_CLOSE	close tray on first open(2)
	    CDO_AUTO_EJECT	open tray on last release
	    CDO_USE_FFLAGS	use O_NONBLOCK information on open
	    CDO_LOCK		lock tray on open files
	    CDO_CHECK_TYPE	check type on open for data

	outputs:
	  Returns the resulting options settings in the
	  ioctl return value.  Returns -1 on error.

	error return:
	  ENOSYS	selected option(s) not supported by drive.




CDROM_CLEAR_OPTIONS		Clear behavior options

	Same as CDROM_SET_OPTIONS, except that selected options are
	turned off.



CDROM_SELECT_SPEED		Set the CD-ROM speed

	usage:

	  int speed;
	  ioctl(fd, CDROM_SELECT_SPEED, speed);

	inputs:
	  New drive speed.

	outputs:	none

	error return:
	  ENOSYS	speed selection not supported by drive.



CDROM_SELECT_DISC		Select disc (for juke-boxes)

	usage:

	  int disk;
	  ioctl(fd, CDROM_SELECT_DISC, disk);

	inputs:
	  Disk to load into drive.

	outputs:	none

	error return:
	  EINVAL	Disk number beyond capacity of drive



CDROM_MEDIA_CHANGED		Check is media changed

	usage:

	  int slot;
	  ioctl(fd, CDROM_MEDIA_CHANGED, slot);

	inputs:
	  Slot number to be tested, always zero except for jukeboxes.
	  May also be special values CDSL_NONE or CDSL_CURRENT

	outputs:
	  Ioctl return value is 0 or 1 depending on whether the media
	  has been changed, or -1 on error.

	error returns:
	  ENOSYS	Drive can't detect media change
	  EINVAL	Slot number beyond capacity of drive
	  ENOMEM	Out of memory



CDROM_DRIVE_STATUS		Get tray position, etc.

	usage:

	  int slot;
	  ioctl(fd, CDROM_DRIVE_STATUS, slot);

	inputs:
	  Slot number to be tested, always zero except for jukeboxes.
	  May also be special values CDSL_NONE or CDSL_CURRENT

	outputs:
	  Ioctl return value will be one of the following values
	  from <linux/cdrom.h>:

	    CDS_NO_INFO		Information not available.
	    CDS_NO_DISC
	    CDS_TRAY_OPEN
	    CDS_DRIVE_NOT_READY
	    CDS_DISC_OK
	    -1			error

	error returns:
	  ENOSYS	Drive can't detect drive status
	  EINVAL	Slot number beyond capacity of drive
	  ENOMEM	Out of memory




CDROM_DISC_STATUS		Get disc type, etc.

	usage:

	  ioctl(fd, CDROM_DISC_STATUS, 0);

	inputs:		none

	outputs:
	  Ioctl return value will be one of the following values
	  from <linux/cdrom.h>:
	    CDS_NO_INFO
	    CDS_AUDIO
	    CDS_MIXED
	    CDS_XA_2_2
	    CDS_XA_2_1
	    CDS_DATA_1

	error returns:	none at present

	notes:
	  Source code comments state:

	    Ok, this is where problems start.  The current interface for
	    the CDROM_DISC_STATUS ioctl is flawed.  It makes the false
	    assumption that CDs are all CDS_DATA_1 or all CDS_AUDIO, etc.
	    Unfortunately, while this is often the case, it is also
	    very common for CDs to have some tracks with data, and some
	    tracks with audio.	Just because I feel like it, I declare
	    the following to be the best way to cope.  If the CD has
	    ANY data tracks on it, it will be returned as a data CD.
	    If it has any XA tracks, I will return it as that.	Now I
	    could simplify this interface by combining these returns with
	    the above, but this more clearly demonstrates the problem
	    with the current interface.  Too bad this wasn't designed
	    to use bitmasks...	       -Erik

	    Well, now we have the option CDS_MIXED: a mixed-type CD.
	    User level programmers might feel the ioctl is not very
	    useful.
			---david




CDROM_CHANGER_NSLOTS		Get number of slots

	usage:

	  ioctl(fd, CDROM_CHANGER_NSLOTS, 0);

	inputs:		none

	outputs:
	  The ioctl return value will be the number of slots in a
	  CD changer.  Typically 1 for non-multi-disk devices.

	error returns:	none



CDROM_LOCKDOOR			lock or unlock door

	usage:

	  int lock;
	  ioctl(fd, CDROM_LOCKDOOR, lock);

	inputs:
	  Door lock flag, 1=lock, 0=unlock

	outputs:	none

	error returns:
	  EDRIVE_CANT_DO_THIS	Door lock function not supported.
	  EBUSY			Attempt to unlock when multiple users
	  			have the drive open and not CAP_SYS_ADMIN

	notes:
	  As of 2.6.8.1, the lock flag is a global lock, meaning that
	  all CD drives will be locked or unlocked together.  This is
	  probably a bug.

	  The EDRIVE_CANT_DO_THIS value is defined in <linux/cdrom.h>
	  and is currently (2.6.8.1) the same as EOPNOTSUPP



CDROM_DEBUG			Turn debug messages on/off

	usage:

	  int debug;
	  ioctl(fd, CDROM_DEBUG, debug);

	inputs:
	  Cdrom debug flag, 0=disable, 1=enable

	outputs:
	  The ioctl return value will be the new debug flag.

	error return:
	  EACCES	Access denied:  requires CAP_SYS_ADMIN



CDROM_GET_CAPABILITY		get capabilities

	usage:

	  ioctl(fd, CDROM_GET_CAPABILITY, 0);

	inputs:		none

	outputs:
	  The ioctl return value is the current device capability
	  flags.  See CDC_CLOSE_TRAY, CDC_OPEN_TRAY, etc.



CDROMAUDIOBUFSIZ		set the audio buffer size

	usage:

	  int arg;
	  ioctl(fd, CDROMAUDIOBUFSIZ, val);

	inputs:
	  New audio buffer size

	outputs:
	  The ioctl return value is the new audio buffer size, or -1
	  on error.

	error return:
	  ENOSYS	Not supported by this driver.

	notes:
	  Not supported by all drivers.



DVD_READ_STRUCT			Read structure

	usage:

	  dvd_struct s;
	  ioctl(fd, DVD_READ_STRUCT, &s);

	inputs:
	  dvd_struct structure, containing:
	    type		specifies the information desired, one of
	    			DVD_STRUCT_PHYSICAL, DVD_STRUCT_COPYRIGHT,
				DVD_STRUCT_DISCKEY, DVD_STRUCT_BCA,
				DVD_STRUCT_MANUFACT
	    physical.layer_num	desired layer, indexed from 0
	    copyright.layer_num	desired layer, indexed from 0
	    disckey.agid

	outputs:
	  dvd_struct structure, containing:
	    physical		for type == DVD_STRUCT_PHYSICAL
	    copyright		for type == DVD_STRUCT_COPYRIGHT
	    disckey.value	for type == DVD_STRUCT_DISCKEY
	    bca.{len,value}	for type == DVD_STRUCT_BCA
	    manufact.{len,valu}	for type == DVD_STRUCT_MANUFACT

	error returns:
	  EINVAL	physical.layer_num exceeds number of layers
	  EIO		Received invalid response from drive



DVD_WRITE_STRUCT		Write structure

	Not implemented, as of 2.6.8.1



DVD_AUTH			Authentication

	usage:

	  dvd_authinfo ai;
	  ioctl(fd, DVD_AUTH, &ai);

	inputs:
	  dvd_authinfo structure.  See <linux/cdrom.h>

	outputs:
	  dvd_authinfo structure.

	error return:
	  ENOTTY	ai.type not recognized.



CDROM_SEND_PACKET		send a packet to the drive

	usage:

	  struct cdrom_generic_command cgc;
	  ioctl(fd, CDROM_SEND_PACKET, &cgc);

	inputs:
	  cdrom_generic_command structure containing the packet to send.

	outputs:	none
	  cdrom_generic_command structure containing results.

	error return:
	  EIO		command failed.
	  EPERM		Operation not permitted, either because a
			write command was attempted on a drive which
			is opened read-only, or because the command
			requires CAP_SYS_RAWIO
	  EINVAL	cgc.data_direction not set



CDROM_NEXT_WRITABLE		get next writable block

	usage:

	  long next;
	  ioctl(fd, CDROM_NEXT_WRITABLE, &next);

	inputs:		none

	outputs:
	  The next writable block.

	notes:
	  If the device does not support this ioctl directly, the
	  ioctl will return CDROM_LAST_WRITTEN + 7.



CDROM_LAST_WRITTEN		get last block written on disc

	usage:

	  long last;
	  ioctl(fd, CDROM_LAST_WRITTEN, &last);

	inputs:		none

	outputs:
	  The last block written on disc

	notes:
	  If the device does not support this ioctl directly, the
	  result is derived from the disc's table of contents.  If the
	  table of contents can't be read, this ioctl returns an
	  error.