linuxaudio.org

On Thu, Jul 28, 2011 at 09:41:09PM +0000, Fons Adriaensen wrote:
> > After reading the kernel source, I think the code in hdsp.c is wrong:

quoted text
> >

> > 		if (hdsp_fifo_wait(hdsp, 0, HDSP_SHORT_WAIT)) {

> > 			hdsp_write(hdsp, HDSP_control2Reg, HDSP_VERSION_BIT);

> > 			hdsp_write(hdsp, HDSP_control2Reg, HDSP_S_LOAD);

> > 			if (hdsp_fifo_wait(hdsp, 0, HDSP_SHORT_WAIT))

> > 				hdsp->io_type = RPM;

> > 			else

> > 				hdsp->io_type = Multiface;

> > 		} else {

> > 			hdsp->io_type = Digiface;

> > 		}

> >

> >

> > Who here owns a Digiface and can confirm or deny that the kernel

> > correctly detects it as Digiface? Same for Multiface, though I guess

> > since it's more or less the default, users wouldn't notice it.

> >

> > What's wrong with the code above? I think all occurrences of

> > HDSP_control2Reg in hdsp_check_for_iobox need to be changed to

> > HDSP_controlRegister and the second hdsp_fifo_wait needs to be inverted.

> >

> > But this is pure guesswork. If I come up with a patch, who here has a

> > RPM, Digiface or Multiface to test it?

>

> I have an RPM wich I'd like to use as a signal generator for measurments

> etc. (it has those nice balanced line outs). But I never managed to make

> it work, despite trying 1000 variations on the code you quoted. It hangs

> in one of the hdsp_fifo_wait(), I don't remember which one.

I blindly wrote a patch:
   http://adi.loris.tv/hdsp_test.tar.bz2
Does it work? If you like and if it's possible to get remote access to

your machine, I'm happy to give it a whirl and start hacking.
I'm somewhat surprised to see so many "wrong" constants in hdsp.c, like

HDSP_fifoData being 368. I have no idea why it is there, I always

thought the fifo write register is 92. (that's what I've changed in the

hdsp_test.tar.bz2, too)
There are even more occurrences of control2Reg in hdsp.c which I would

change to controlRegister, especially in

snd_hdsp_load_firmware_from_cache. But it cannot be totally wrong,

because I guess it must be working for some users...
Cheers

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