This implements the audio control or volume read support as needed by
some systems. A Conectiva Parolin system required this to detect an IDE
device as CD-ROM, through the CDVOLREAD ioctl.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
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