Re: [PATCH v5 2/3] mfd: lp873x: Add lp873x PMIC support

From: Lee Jones
Date: Tue Aug 09 2016 - 05:43:15 EST


On Mon, 08 Aug 2016, Keerthy wrote:
> On Friday 05 August 2016 02:31 PM, Lee Jones wrote:
> > On Fri, 05 Aug 2016, Keerthy wrote:
> > > On Friday 05 August 2016 01:33 PM, Lee Jones wrote:
> > > > On Wed, 29 Jun 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).
> > > > >
> > > > > Signed-off-by: Keerthy <j-keerthy@xxxxxx>
> > > > > ---
> > > > >
> > > > > Changes in v4:
> > > > >
> > > > > * Added Author.
> > > > > * Added the mfd_cell for gpio.
> > > > >
> > > > > Changes in v3:
> > > > >
> > > > > * Reordered the probe code.
> > > > > * Fixed Typo in Kconfig description.
> > > > > * Removed unused member from struct lp873x.
> > > > >
> > > > > drivers/mfd/Kconfig | 14 +++
> > > > > drivers/mfd/Makefile | 2 +
> > > > > drivers/mfd/lp873x.c | 99 +++++++++++++++++
> > > > > include/linux/mfd/lp873x.h | 264 +++++++++++++++++++++++++++++++++++++++++++++
> > > > > 4 files changed, 379 insertions(+)
> > > > > create mode 100644 drivers/mfd/lp873x.c
> > > > > create mode 100644 include/linux/mfd/lp873x.h

[...]

> > > > > +static const struct i2c_device_id lp873x_id_table[] = {
> > > > > + { "lp873x", LP873X },
> > > > > + { "lp8732", LP873X },
> > > > > + { "lp8733", LP873X },
> > > >
> > > > Do you use these IDs at any point?
> > >
> > > I have lp8733 and lp8732 at the moment. They are register exact but
> > > different parts none the less. Hence having separate strings. As of now no
> > > differences seen in gpio/regulator modules so not using them anywhere.
> >
> > I have a patch-set pending on the I2C list that removes all unused
> > 'struct i2c_device_id' tables. To identify which ones are in use and
> > which ones can be removed, it would help if you could remove the
> > unused .id field.
>
> I guess you are referring to this:
>
> http://www.gossamer-threads.com/lists/linux/kernel/2457552
>
> I applied the above series and i see that by using driver_new in lp873x
> MFD driver i no longer need the mandatory i2c_device_id. Thanks.
> I will send a series on top of your i2c set v5 without any unused device_id.
> I will add a dependency on your set.

I would not do that if I were you. That set has been pending for
years. I'm just saying, when that patch-set is accepted, it will be
easier to identify removable tables if they do not contain populated,
but unused .id entries.

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