Re: [PATCH v2 1/2] regulator: act8945a: add regulator driver for ACT8945A

From: Lee Jones
Date: Thu Jan 14 2016 - 01:20:45 EST


On Thu, 14 Jan 2016, Yang, Wenyou wrote:

> > -----Original Message-----
> > From: Peter Korsgaard [mailto:jacmet@xxxxxxxxx] On Behalf Of Peter Korsgaard
> > Sent: 2016å1æ13æ 22:22
> > To: Yang, Wenyou <Wenyou.Yang@xxxxxxxxx>
> > Cc: Liam Girdwood <lgirdwood@xxxxxxxxx>; Mark Brown <broonie@xxxxxxxxxx>;
> > Rob Herring <robh+dt@xxxxxxxxxx>; Pawel Moll <pawel.moll@xxxxxxx>; Mark
> > Rutland <mark.rutland@xxxxxxx>; Ian Campbell <ijc+devicetree@xxxxxxxxxxxxxx>;
> > Kumar Gala <galak@xxxxxxxxxxxxxx>; Krzysztof Kozlowski
> > <k.kozlowski@xxxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx; Ferre, Nicolas
> > <Nicolas.FERRE@xxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; Javier Martinez
> > Canillas <javier@xxxxxxxxxxxx>; Lee Jones <lee.jones@xxxxxxxxxx>; linux-arm-
> > kernel@xxxxxxxxxxxxxxxxxxx
> > Subject: Re: [PATCH v2 1/2] regulator: act8945a: add regulator driver for
> > ACT8945A
> >
> > >>>>> "Wenyou" == Wenyou Yang <wenyou.yang@xxxxxxxxx> writes:
> >
> > > This patch adds new regulator driver to support ACT8945A MFD > chip's
> > regulators.
> >
> > > The ACT8945A has three step-down DC/DC converters and four > low-dropout
> > regulators.
> >
> > > Signed-off-by: Wenyou Yang <wenyou.yang@xxxxxxxxx>
> >
> > Isn't the regulator part of the act8945a identical to act8865? Can't we just use the
> > existing act8865-regulator.c driver? (E.G. support 8865 variant in the mfd driver,
> > but only register the regulator sub device?)
>
> Yes, the regulator part of the act8945a is identical to act8865.
>
> But the act8865-regulator driver is a struct i2c_driver, and the mfd sub-device driver is a platform_driver driver, it is not easy to use it.

Take a look at some existing files with the pattern
drivers/mfd/*{spi,i2c,core}.c to see how this might be possible.

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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