Volume boost on CD channel by starting to play CD???

Alex Butche (linkern@cocoa.demon.co.uk)
Sat, 2 Oct 1999 20:15:14 +0100 (GMT)


Hi all -

I've picked up a Pace TV card that connects to one of the internal CD audio
inputs of my Creative Labs SB16. I have a Creative 24x CD2422E ATAPI CD-Rom
attached to another CD audio input. I realise that the two inputs are both
on the same channel of the sound card.

If I start up a video4linux client the audio is initially quiet, but if I
start up a CD player app and start playing an audio CD then stop again, the
volume of that channel increases to a much more sensible level.

If I rmmod bttv.o, and reload, the volume level is quiet until the same
procedure is repeated.

Any ideas on why this should be the case? Would it be possible to create a
small utility to do what the CD player does without an audio CD being loaded
in the drive (or better, have bttv initialise the sound card in the same
way)? I presume the magic is something amongst:

ioctl(4, CDROMPLAYMSF, 0xbffff71c) = 0
ioctl(4, CDROMSUBCHNL, 0xbffff6ec) = 0
ioctl(4, CDROMSUBCHNL, 0xbffff878) = 0
ioctl(4, CDROMSTOP, 0xbffff760) = 0

(If anyone needs further info on my hardware, just ask... :)

Other than that, it's all working well - thanks for all your work!

Best Regards,
Alex.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/