[linux-dvb] Re: Howto read audio register of av7110, SPDIF dead

["Dr. Werner Fink" <werner@suse.de>]

On Mon, Feb 07, 2005 at 12:13:22AM +0100, Johannes Stezenbach wrote:
> > I want to write the content of avermedia Register 0x6C000000 to the kernel log 
> > for debugging.
> 
> av7110 (chip made by TI) does have nothing to do with avermedia (card vendor).
> Anyway, the firmware doesn't implement a command to do that. Also, since
> you say that SPDIF ceases to work after initializing the MSP3415 I guess
> it has nothing to do with the audio decoder inside the av7110.
> 
> Maybe Werner Fink has some idea?

The firmware does provide the `COMTYPE_REQUEST' command `ReqRegister' [1]
You could read the Audio Control and the Audio Status Register
accordingly to the open av7110.pdf.  The only problem is: the
addresses or better the offset within the Audio Base 0x6C000000
to the addresses both registers are wrong in that document.

If Johannes gives the OK, it would be easy to provide the offsets.
Currently those values are closed :-/

> > I tried to find out if the SPDIF is driven over the avermedia by beeping the 
> > board out weeks ago....
> > I have to say...I don't know, no success.
> > That's the reason why i want to debug registers.

Guess: the not documented S/P-DIF bit in the Audio Control Register
for disabling the S/P-DIF interface was set to high.  I've found
this register bit in the headers of the firmware during the search
for setting the non-audio status bit of the S/P-DIF interface.


      Werner

[1] -> linux/drivers/media/dvb/ttpci/av7110_hw.h

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