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

Beomho Seo
2015-03-26T23:49:23Z

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.
If you think this patch will suitable for battery tree(or other tree),
I would like request for merge battery tree.
Also, I will send again this patch and device tree binding document.

Best regards,
Beomho Seo