[ANNOUNCE]: Audio support for cx88 cards

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Hello everyone;

	We're happy to announce V4L support for DMA audio in Conexant CX88x
based cards (i.e., direct access to audio through the PCI bus, without
usage of a loopback cable to connect to the line-out of the sound card)
is now available in the CVS tree. (Philips SAA713x and Conexant BT878
cards already had support, this was the only one missing). That support
is provided using the Linux ALSA sound stack, by the module cx88-alsa.
	This is particularly important for those who own cards without any
line-out jack or internal connector to plug a physical line into the
sound-card (like the Hauppauge HVR1100 or most PCMCIA cards), but can be
used by anyone.
	Some programs (mplayer, that I know of, maybe others?) already support
reading these sound streams directly, but in most cases, and just like
the saa7134, bt87x, or even the usbaudio support for USB adapters, cx88
still requires an external program to copy the sound from the TV card to
the sound card (a program like sox, or "arecord | aplay"), which
eventually leads to Audio/Video synchronization problems (since the TV
app and the sound copying app don't have any way to synchronize between
them). We expect the maintainers for the existing TV programs will
eventually support reading sound in their apps so A/V sync problems
win't be an issue anymore (*hint hint*, *nudge nudge*).
	For now, use sox like this:

 $ sox -t ossdsp -r 48000 -b -c 2 /dev/dsp -t ossdsp /dev/dsp2
	
	or arecord like this:

 $ arecord -D hw:2,0 -r 48000 -c 2 -f S16_LE | aplay -

(the "dsp2" or "hw:2" values may need adjusting. cat /proc/asound/cards
to see which index it got in your system)

	Anyhow... This module has been successfully tested in 3 different
boards (1 analog, 2 hybrids), but may still have its quirks or problems.
So if you own an analog or hybrid cx88 card (DVB cards don't need this,
as the sound stream comes inside the MPEG2-TS), especially one that
doesn't have a line-out (and you don't have any sound working), please
test this. Just checkout current CVS, build, and install, and you should
have cx88-alsa available as a module.	
	We'd also like to thank Hauppauge (especially Steve Toth) for their
support while we tried to get this running. Thanks guys!

--
RC

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