Re: [PATCH v7 2/5] power: max77843_charger: Add Max77843 charger device driver

Lee Jones
2015-03-27T07:58:06Z

On Fri, 27 Mar 2015, Beomho Seo wrote:
> On 03/26/2015 10:54 PM, Lee Jones wrote:
> > On Thu, 26 Mar 2015, Beomho Seo wrote:
> >> On 03/24/2015 05:38 PM, Krzysztof Kozlowski wrote:
> >>> 2015-03-24 9:01 GMT+01:00 Beomho Seo <beomho.seo@samsung.com>:
> >>>> On 03/10/2015 10:44 PM, Beomho Seo wrote:
> >>>>> On 03/09/2015 09:13 PM, Krzysztof Kozlowski wrote:
> >>>>>> On pon, 2015-03-09 at 20:46 +0900, Beomho Seo wrote:
> >>>>>>> On 03/09/2015 08:02 PM, Krzysztof Kozlowski wrote:
> >>>>>>>> 2015-03-09 1:35 GMT+01:00 Beomho Seo <beomho.seo@samsung.com>:
> >>>>>>>>> On 03/08/2015 05:13 AM, Sebastian Reichel wrote:
> >>>>>>>>>> On Mon, Mar 02, 2015 at 07:10:35PM +0900, Jaewon Kim wrote:
> >>>>>>>>>>> From: Beomho Seo <beomho.seo@samsung.com>
> >>>>>>>>>>>
> >>>>>>>>>>> This patch adds device driver of max77843 charger. This driver provide
> >>>>>>>>>>> initialize each charging mode(e.g. fast charge, top-off mode and constant
> >>>>>>>>>>> charging mode so on.). Additionally, control charging paramters to use
> >>>>>>>>>>> i2c interface.
> >>>>>>>>>>>
> >>>>>>>>>>> Cc: Sebastian Reichel <sre@kernel.org>
> >>>>>>>>>>> Signed-off-by: Beomho Seo <beomho.seo@samsung.com>
> >>>>>>>>>>
> >>>>>>>>>> Reviewed-By: Sebastian Reichel <sre@kernel.org>
> >>>>>>>>>>
> >>>>>>>>>> I can't take it as is, since it depends on the private header file
> >>>>>>>>>> of PATCHv1.
> >>>>>>>>>>
> >>>>>>>>>> -- Sebastian
> >>>>>>>>>>
> >>>>>>>>>
> >>>>>>>>> This patch reviewed by Sebastian.
> >>>>>>>>> Could you Please merge that your git tree ?
> >>>>>>>>
> >>>>>>>> Hi,
> >>>>>>>>
> >>>>>>>> ... and again we are adding a new driver for very similar chipset to
> >>>>>>>> already supported. I looked at spec and the charger's registers are
> >>>>>>>> almost the same as for max77693. Their layout and addresses are the
> >>>>>>>> same. I see some minor differences, probably the most important would
> >>>>>>>> be different values current (fast-charge, top-off). But still 90% of
> >>>>>>>> registers are the same... Do we really have to add new driver?
> >>>>>>>>
> >>>>>>>> Best regards,
> >>>>>>>> Krzysztof
> >>>>>>>>
> >>>>>>>
> >>>>>>> Hi,
> >>>>>>>
> >>>>>>> Thank you for your comment. As you say, both chip set are similar.
> >>>>>>> But new driver need for support max77843. It is support different below
> >>>>>>> - Provide Battery presence information.
> >>>>>>
> >>>>>> Another set of power supply properties could be added for that chip.
> >>>>>> This way the get_property() function would be the same but actually the
> >>>>>> POWER_SUPPLY_PROP_PRESENT won't be called for max77693.
> >>>>>>
> >>>>>>> - Can OTG FET control.
> >>>>>>
> >>>>>> Where the OTG FET feature is it enabled in your driver? I couldn't find
> >>>>>> it.
> >>>>>>
> >>>>>
> >>>>> Sorry. This driver don't control OTG FET feature.
> >>>>>
> >>>>>>> - Bigger Fast charge current, Top Off current Threshold selection.
> >>>>>>> - Various and bigger OTG current limitation.
> >>>>>>> - Bigger primary charger termination voltage setting.
> >>>>>>> - Different maximum input current limit selection(Different step).
> >>>>>>
> >>>>>> Yes, I mentioned some of these differences (the Fast/top-off
> >>>>>> differences). These are differences in values so it does not require new
> >>>>>> driver. There is need to develop new driver just to support different
> >>>>>> current (3.0 A instead of 2.1 A) or voltage threshold.
> >>>>>>
> >>>>>
> >>>>> They are different charging current, OTG current limitation, top off current,
> >>>>> charging limitation value. In case OTG current limitation different not
> >>>>> limitation value but using register bit(max77843 use[7:6] max77693 use[7]
> >>>>> bit only). Even if this driver not support all feature, some register
> >>>>> different with max77693(support value, use register bit).
> >>>>>
> >>>>> If this driver will combined with max77693 may even be beneficial for
> >>>>> new Maxim driver. But the present, this driver is related with
> >>>>> max77843 core driver and max77843-regulator. So I hope this driver
> >>>>> merge first. And then will extend two driver(max77843 charger and max77693 charger).
> >>>
> >>> I still prefer merging common drivers into one instead of creating
> >>> some more of them.
> >>> However I understand your point and I am not entirely opposed against.
> >>> Especially that you invested quite a bit of time for developing this
> >>> and my feedback was quite late. To summarize I am fine with your
> >>> approach.
> >>>
> >>> Best regards,
> >>> Krzysztof
> >>>
> >>
> >> Dear Lee Jones,
> >>
> >> Could you please merge that your git tree ?
> >
> > Sorry, I'm lost. Why am I taking this though the MFD tree? What
> > patches are left? Where are they going? Am I taking any other
> > patches?
> >
>
> Max77843 charger driver is max77843 mfd core dependency.

What kind of dependancy? Runtime or build? Where is the patch that
it depends on? Is it in -next for in Mainline already?

> If you think this patch will suitable for battery tree(or other tree),
> I would like request for merge battery tree.

If this patch has no build dependencies on patches which are in -next,
but not in Mainline then it will have to go in via the same tree that
the dependencies were applied to. If the dependencies are already in
Mainline, or they are not build-deps, then it should go in via the
correct tree, which I believe is Sebastian's tree.

> Also, I will send again this patch and device tree binding document.

Either way you should do that. Mark them as RESEND instead of PATCH
and apply all of the Acks you have accumulated so far.

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