Re: [PATCH v2] MediaTek PMIC support

[Matthias Brugger <matthias.bgg@gmail.com>]

2015-01-29 15:27 GMT+01:00 Sascha Hauer <s.hauer@pengutronix.de>:
> On Thu, Jan 29, 2015 at 01:39:42PM +0100, Matthias Brugger wrote:
>> Hi Sascha,
>>
>> 2015-01-26 12:47 GMT+01:00 Sascha Hauer <s.hauer@pengutronix.de>:
>> > Olof, Arnd,
>> >
>> > OK to put the driver into drivers/soc/mediatek? Can you take these
>> > patches?
>>
>> How does this patches fit together with the one James clock framework patches?
>> Both use the same compatible "mediatek,mt8135-infracfg" and
>> "mediatek,mt8135-pericfg".
>>
>> I had a look on other implementations and they attach the reset
>> controller to the clk driver, if they share the same hw block.
>> Might we run into problems if we implement the clocks in the mfd, as
>> we need the clocks early in boot (e.g. for the timer)?
>
> From my experience the clocks are needed by the timer before any driver
> initializes.
>
>>
>> In mt6589 pericfg apart from the clocks and reset controller provides
>> registers for AXI bus control and USB wakeup and USB clock selection.
>> The infracfg block provides top AXI bus fabric control signals and
>> remap registers for the modem.
>> Mike, Stephen, what do you think. Can we implement the clk in a mfd
>> driver? Or do you prefer to implement the whole block in the clk
>> driver?
>
> Currently the clk support uses regular CLK_OF_DECLARE which handles the
> clock part of pericfg/infracfg and then later a regular driver for
> pericfg/infracfg comes and handles the rest of the functionality. Since
> both use separate registers in the device register space it should work
> fine.

It should work until some driver start to use request and map, as you
provide the whole register space.
If you want to implement drivers for pericfg/infracfg like this, why
don't you implement the reset controller in drivers/reset?

Anyway I'm not really happy with the solution of having several device
drivers for the same dts compatible string.

>
> Sascha
>
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