Re: [PATCH v2 1/5] mmc: host: sdhci-s3c: Add broken-voltage DT property for broken voltage quirk

[Chris Ball <cjb@laptop.org>]

Hi Tomasz,

On Wed, Sep 19 2012, Tomasz Figa wrote:
> Hi Chris,
>
> On Wednesday 19 of September 2012 01:42:01 Chris Ball wrote:
>> On Tue, Sep 04 2012, Tomasz Figa wrote:
>> > Some boards use fixed voltage regulator for vmmc supply (e.g. for eMMC
>> > memories). MMC_CAP2_BROKEN_VOLTAGE must be enabled for them to operate
>> > correctly.
>>>
>> Is there a reason we can't make this a property on the regulator instead?
>
> Is there a reason we can't make this a property of the mmc subsystem? ;)
>
> Now, seriously, could you elaborate on this a bit more? Do you mean that a 
> regulator should provide a dummy set voltage operation that would accept 
> any voltage?

Sorry for the terseness.

It seems like we're encoding exactly the same information twice in two
different subsystems -- I don't see the point, so I'd like to think
about how we could do better.

For example, if we're only concerned about fixed regulators, could we
just detect a fixed regulator in the driver and avoid the failing call
to regulator_set_voltage() directly, without needing to go via this
capability?  Seems like the capability doesn't tell us anything we
couldn't already have known.

Thanks,

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child