Re: [PATCH v2 2/3] mfd: lp873x: Add lp873x PMIC support

[Keerthy]

On Tuesday 17 May 2016 01:31 PM, Lee Jones wrote:
> On Fri, 13 May 2016, Keerthy wrote:
> > On Thursday 12 May 2016 06:48 PM, Lee Jones wrote:
> > > On Tue, 10 May 2016, Keerthy wrote:
> > >
> > > > The LP873X chip is a power management IC for Portable Navigation Systems
> > > >      and Tablet Computing devices. It contains the following components:
> > > >
> > > >       - Regulators.
> > > >       - Configurable General Purpose Output Signals(GPO).
> > > >
> > > > PMIC interacts with the main processor through i2c. PMIC has
> > > > couple of LDOs(Linear Regulators), couple of BUCKs (Step-Down DC-DC
> > > > Converter Cores) and GPOs(General Purpose Output Signals). At this
> > > > time only the regulator functionality is made available.
> > > >
> > > > Signed-off-by: Keerthy <j-keerthy@xxxxxx>
> > > > ---
> > > >
> > > > Changes in v2:
> > > >
> > > >    * Used mfd_add_devices instead of of_pltaform_populate.
> > >
> > > Didn't see this conversation, but of_platform_populate () is usually
> > > okay?
> >
> > https://lkml.org/lkml/2016/5/6/244.
>
> Did Mark tell you why you shouldn't be using it?

"You shouldn't be using that, you should just have a table of subdevices
in the MFD"

I inferred not to use of_platform_populate and make use of 
mfd_add_devices instead.

Please correct me if am wrong.

> > > >   drivers/mfd/Kconfig        |  15 +++
> > > >   drivers/mfd/Makefile       |   2 +
> > > >   drivers/mfd/lp873x.c       |  98 +++++++++++++++++
> > > >   include/linux/mfd/lp873x.h | 265 +++++++++++++++++++++++++++++++++++++++++++++
> > > >   4 files changed, 380 insertions(+)
> > > >   create mode 100644 drivers/mfd/lp873x.c
> > > >   create mode 100644 include/linux/mfd/lp873x.h
>
> [...]
>
> > > > +/**
> > > > + * struct lp873x - state holder for the lp873x driver
> > > > + * Device data may be used to access the LP873X chip
> > > > + */
> > > > +struct lp873x {
> > > > +	struct device *dev;
> > > > +	unsigned long id;
> > > > +	u8 rev;
> > > > +	struct mutex lp873_lock;	/* lock guarding the data structure */
> > > > +	struct regmap *regmap;
> > >
> > > Are all of these used in >1 driver?
> >
> > Apart from id and rev all are used.
>
> Then why are id and rev in there?