[PATCH v4 0/5] bcm2835: auxiliar device support for spi

Stephen Warren swarren at wwwdotorg.org
Mon Sep 21 19:15:45 PDT 2015

On 09/15/2015 10:39 PM, Martin Sperl wrote:
>> On 16.09.2015, at 06:11, Stephen Warren <swarren at wwwdotorg.org> wrote:
>> I believe it's legitimate for a compatible property to include a
>> particular value (e.g. ns16550) if and only if a driver that knows
>> solely about that compatible value (i.e. just the 16550 standard
>> registers) can operate the HW without issue. I don't believe that's true
>> in this case since the aux enable HW bit must be programmed and does not
>> exist in standard 16550 HW block.
> But following that argument it would have also been “acceptable” to define 
> the compatible=“regmap" approach for this auxiliar register set,
> which I used in V2...

I don't believe so, no. The separate HW blocks still need to be
represented explicitly rather than lumping them together with multiple
drivers jumping on the shared aux registers.

> But now that we got the clock approach it works even better...

Yes, that approach is good.

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