Messages in this thread | | | Date | Tue, 25 Oct 2011 10:36:34 +0200 | From | Mark Brown <> | Subject | Re: [PATCHv4 4/6] input/cma3000_d0x: Add CMA3000 spi support |
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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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