[alsa-devel] [PATCH] ALSA: Support Media Vision Jazz16 chips

[Rene Herman]

On 03/31/2007 06:22 PM, Rask Ingemann Lambertsen wrote:

> Thanks for your testing. Could you also test playback of 16-bit
> sounds through an 8-bit DMA channel in DOS?

This works fine. With the "8 bit DMA" set to 1 and the "16 bit DMA" to 
3, 8 and 16-bit wave files play without problem.

> While IRQ 15 works fine for me with an AD1816A card, I can not get
> IRQ 15 to work with the Jazz on the same machine. Over the weekend
> I'll try to use autoprobing to figure out exactly what is and isn't
> supported. I'll also look at circuit board traces and the ISA bus
> connector pinout for clues.

I got IRQ 15 to work. From looking at the traces, I could identify 
jumpers J10 as the "CD-ROM IRQ", with it being set to IRQ15 (with 
possibilities 11, 12 and 15). When I set it to something else, IRQ15 
starts working both for the Jazz and the MPU-401 IRQ. That is, all of 3, 
5, 7, 9, 10 and 15 now work for both IRQs for me.

> I also tried 0x270, but it didn't work. Maybe due to worries about
> the possibility of a parallel port at 0x278. I also tried 0x340,
> 0x350, 0x360 and 0x370 for the MPU port, but also with no luck.

As said, mine has dip-switches with two marked MAB0 and MAB1 (and one 
MPUDIS) and checking that, yes, the MPU-401 _is_ in fact on the bus 
without any initialization having been done, at the address (300, 310, 
320, 330) configured by MAB0-1. So yes, having only two jumpers for that 
will mean those are the only options.

With DAB2-0 (those other switches) set to 000, the Jazz itself is not on 
the bus, and it's getting a bit late to test, but I expect that 6 out of 
the remaining 7 possible value will be 210, .., 260. Will test later.

>> Lastly, how would you feel about setting the DOS/Windows default 
>> resource values as the preffered values and all the others as mere 
>> acceptable?
> 
> I'll leave that up to Adam Belany. Personally, I have never
> understood the point of having a preferred option with the default
> values and an acceptable one with all the possible ones. A naive PnP
> stack risks that the defaults take required resources away from
> another card while a sofisticated PnP stack will most likely overrule
> the defaults anyway to prevent resource starvation.

I do believe there's a point; let's pretend it's 1995 and we're sharing 
this card with other Non-PnP ISA cards in the machine. Through jumpers 
and/or the DOS setup software, we've created a conflict-free setup and 
are using the default values for that -- some of those old games we 
still enjoy playing won't even allow anything other than 220 or 240. At 
210 we placed an ISA radio card.

Now linux boots, doesn't know about the radio card, and sets our Jazz to 
210. Crap!

>    You can change the second last DMA definition to
> 
> 	{ .map = (1 << 1) | (1 << 3) | (1 << 5) | (1 << 7),
> 	  .flags = IORESOURCE_DMA_8AND16BIT, },

Okay.

Rene.