[PATCH 2/2] spi: orion: add support for multiple chip selects

[Mark Brown]

On Mon, Jul 28, 2014 at 08:25:14AM +0200, Sebastian Hesselbarth wrote:

> So, "num-cs" describes the number of *available* chip select signals. As
> they can comprise extra cs lines that are GPIO and not dedicated
> controller signals (native above), it cannot be something the driver
> knows.

Yes, indeed.  Though given that we also need a way to pass in the GPIOs
for the chip selects which isn't standardised at the minute it's all a
bit of a mess right now.

> As long as you only use native cs lines, omit the cs-gpios property, if
> there is any GPIO cs lines, insert <0> where you want native ones.

Right, something like that should be usable.  We also need a way to say
which native chip select to set when using a GPIO chip select if the
GPIO chip selects go beyond the native ones and none of the native ones
are masked by GPIOs.

> Although, I wonder how the driver learns about reg = <1> is actually the
> controller's cs0 in the example above?

Interesting question...
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