Re: [PATCH 0/4] spi: dw: fixes, and manages resources migration

[Gerhard Sittig <gsi-ynQEQJNshbs@public.gmane.org>]

On Thu, Dec 26, 2013 at 14:12 +0200, Baruch Siach wrote:
> 
> [ ... GPIO controlled CS lines for SPI ... ]
> 
> Thanks for the head up. I was considering adding a spi-dw specific "dummy-cs" 
> property, to be used for cs-gpio numbers that are higher than num-cs.

Look at it the other way for a moment.  These GPIO backed CS
lines aren't "dummies", having control over them and having more
than four of them is not at all exceptional or strange, it's the
actual motivation for cs-gpios in the first place.  And all of
these GPIO lines are "real" and useful.

Try to see the internal CS lines in the hardware of the SPI
controller as the exception instead. :) These are the ones that
are rather limited, both in their number and in their behaviour,
and are of questionable use.  These internal lines of
uncontrollable behaviour only get used in the absence of a GPIO
spec for the CS line.


virtually yours
Gerhard Sittig
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