On Thursday 15 November 2012 10:15:08 Mark Brown wrote:
> On Thu, Nov 15, 2012 at 12:33:31AM +0100, Jonas Gorski wrote:
> > On 15 November 2012 00:17, Mark Brown
> 
> > > This is only going to work around a relatively small subset of cases so
> > > it doesn't seem worth rushing in.  The normal fix for such issues is to
> > > control /CS as a GPIO.
> 
> > Well, one of the "small" subsets is SPI attached flash, those need
> > write then read or write then write with CS asserted for most
> > operations, too. And I'm not sure if controlling CS as a GPIO is an
> 
> This is the case for essentially all devices with registers too.  If it
> were always fixing the issue (eg, by allocating a buffer if the one
> supplied isn't suitable) that'd be fine but instead it's going to work
> some but not all of the time which seems non-ideal

Devices that we care about on bcm63xx, which are connected to these built-in
chip-selects are:
- SPI flashes
- SPI Ethernet switches (register based)
- SPI SLIC/SLAC (register based as well)

I assume any hardware design which needs specific CS treatment would wire it
to a spare GPIO to fully control its assertion.

Would you accept this patch provided that Jonas updates his commit log with
this description of devices we support?
--
Florian


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