2008/1/3, David Brownell <[EMAIL PROTECTED]>:
> On Thursday 03 January 2008, Gernot Kvas wrote:
> > I have implemented a DMA/PIO driven SPI driver for the ARM based
> > ns9xxx SoCs, largely based on the driver for the omap2. I'm using the
> > mmc_spi stuff from the mm patches, currently 2.6.23-mm1.
>
> ISTR some initial merge glitches, but maybe they were gone by then.
> I'd still recommend using more current code; especially with the
> 2.6.24 release nearly upon us.  :)

I'm looking forward to 2.6.24. Anyone volunteered to implement the
spi-subsystem primitives to allowed mmc_spi on a shared bus?

> > subsequent CMD25 or CMD24 would fail. Both commands expect a R1
> > response, 8-bits. However, prior to what looks like a 8-bit response,
> > I read a couple of 0xFF (which is normal) and then suddenly a 0xFE. It
> > seems as if the card goes low too early. Any ideas, hints?
>
> That sounds a bit familiar.  Does that happen with all cards, or
> just with ones from one particular vendor?  Is that driver version
> using SPI_MODE_0 or SPI_MODE_3?

It should be using SPI_MODE_0. As far as I can remember on the scope
traces, that should be true.

> And is your SPI controller driver keeping chipselect low during
> that whole period?

I tried it both with a toggling chipselect (which would be the
default, as the ns9xxx toggles if you write bytewise and as I
suspected this, I manually changed the chipselect in a driver
callback. No change, even with the chipselect low over the entire
period.

I only have cards from that manufacturer to try out, however, I will
have access to an older card at the weekend to try that out.

Cheers,

Gernot

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