2003-06-14 12:12:58

by linux-kernel

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Subject: 2.4.21: cmedia PCM not working

Hi,

I just compiled and tried kernel 2.4.21. All seems fine except that I
have no sound over /dev/dsp (other sources like e.g. "line" work fine).

My soundchip is a SiS 7012, which seems to have a cmedia CMI65.

Having a look at the changes, I see this new line in ac97_codec.c:

{0x434D4941, "CMedia", &cmedia_ops, AC97_NO_PCM_VOLUME },

Commenting out only the AC97_NO_PCM_VOLUME field (and leaving the rest of
the line) makes my audio work again.
While indeed the volume slider never allowed me to linearly control
the volume, it DOES have an effect:
- at level 0 there is no sound
- at any oher level, there is pcm sound. The volume is in no way
influenced by the value, as long as it's not zero

So I suspect that while indeed you don't want a pcm volume level for
a CMI65, just adding that line also gets rid of some needed
initialization.
--
#define struct union /* Great space saver */


2003-06-14 12:45:57

by Alan

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Subject: Re: 2.4.21: cmedia PCM not working

On Sad, 2003-06-14 at 13:25, Ton Hospel wrote:
> So I suspect that while indeed you don't want a pcm volume level for
> a CMI65, just adding that line also gets rid of some needed
> initialization.

Correct - should be fixed in -ac. You need to turn off the mute in the
init code.