Re: [linux-audio-user] Disabling cardbus prefetch for Echo Indigo

Paul Davis wrote:
> On Tue, 2005-08-16 at 13:34 +0100, Jon Stutters wrote:
>
>>Hi all,
>>
>>I'm trying to get an Echo Indigo IO working under Gentoo 2.6.12 kernel.
>> The card's recognized correctly by ALSA and I can play through it but
>>all output is badly distorted.
>>
>>I had the same problem on this laptop under Windows and fixed it using a
>>utility from Echo to disable prefetch for the cardbus chipset (ENE
>>CB1410). Does anyone know how to disable prefetch under Linux? I've
>>had a go at hacking the cardbus driver source but I've not got the right
>>result yet.
>
> i would have thought that this was susceptible to the same kind of
> solution that Ico used to solve a similar problem with the RME HDSP
> pcmcia card. rather than hack the driver, use setpci and its cousins to
> investigate and modify the state of the PCI device registers. you will
> need to find out how to get the state in windows before and after that
> utility runs, and then take the information on what it changed and apply
> it to setpci.

You're a lifesaver Paul thanks very much.

For the record:
To disable prefetch on the ENE CB1410 and fix playback with the Echo
Indigo IO change C8h to 0200h. For example:

setpci -s 02:04.0 c8.W=2,0
(where 02:04.0 is the cardbus controller address)

Cheers,
Jon Stutters
Received on Tue Aug 16 20:15:06 2005