Re: [PATCH 2/3] mfd: tps65090: Stop caching registers

[Doug Anderson]

Mark,

On Wed, Apr 16, 2014 at 3:13 AM, Mark Brown <broonie@xxxxxxxxxx> wrote:
> On Wed, Apr 16, 2014 at 10:59:22AM +0100, Lee Jones wrote:
>
>> > NOTE: the IRQnMASK and CG_CTRLn registers are the exception and could
>> > be cached.  If we find that we spend a lot of time reading those we
>> > can turn on cache for just those registers.
>
>> > -static bool is_volatile_reg(struct device *dev, unsigned int reg)
>> > -{
>> > -   if ((reg == TPS65090_INT_STS) || (reg == TPS65090_INT_STS2))
>> > -           return true;
>> > -   else
>> > -           return false;
>> > -}
>> > -
>
>> I don't know enough about Regmap internals to know what this actually
>> affects in real terms.
>
>> Mark,
>>   Does this change seem sane to you?
>
> It does what it says, it stops us caching stuff.  It would seem better
> to do what the changelog suggests above and keep caching the registers
> that can be cached - especially the interrupt masks, they should get
> read in the interrupt path and that tends to be a bit latency sensitive.

Done
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