Re: [PATCHv4 4/6] input/cma3000_d0x: Add CMA3000 spi support

From: Mark Brown
Date: Tue Oct 25 2011 - 04:36:37 EST

On Tue, Oct 25, 2011 at 09:32:27AM +0100, Jonathan Cameron wrote:
> On 10/25/11 08:24, Ricardo Ribalda Delgado wrote:

> > It is not on linux-next, and also it cannot be used directly, in order
> > to read you have to do set reg= (reg << 2) | 2; And AFAIK it is not
> > supported by the regmap

> My gut feeling is it would easy enough to add if it can't currently
> be done. Mark?

That should be trivial to add - the | 2 bit is already supported in
-next and will be sent to Linus this merge window, adding the shift is
just a simple matter of programming.

> Gains here are leveraging the bus abstractions from there. There aren't
> enough registers to gain from caching etc.

Depends on the workload more than the number of registers - if you're
able to eliminate enough reads then it can give a bit of a performance
boost. But it's completely optional either way.
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