Re: [PATCH v6 1/2] dt-bindings: leds: Add bindings for lm3697 driver

From: Jacek Anaszewski <jacek.anaszewski@gmail.com>
To: Dan Murphy <dmurphy@ti.com>, Pavel Machek <pavel@ucw.cz>
Cc: robh+dt@kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org
Subject: Re: [PATCH v6 1/2] dt-bindings: leds: Add bindings for lm3697 driver
Date: Tue, 11 Sep 2018 20:27:50 +0200	[thread overview]
Message-ID: <5127d46f-2d43-41e8-dde0-5ee42a9d47bb@gmail.com> (raw)
In-Reply-To: <20d9ea9e-bbb8-2240-97cc-615e3fbcef8c@ti.com>

Dan,

On 09/10/2018 09:51 PM, Dan Murphy wrote:
> Jacek
> 
> On 09/10/2018 02:07 PM, Jacek Anaszewski wrote:
>> Dan, Pavel,
>>
>> On 09/10/2018 04:37 PM, Dan Murphy wrote:
>>> Jacek
>>>
>>> On 09/08/2018 02:53 PM, Jacek Anaszewski wrote:
>>>> Dan,
>>>>
>>>> On 09/07/2018 03:52 PM, Dan Murphy wrote:
>>>> [...]
>>>>>>
>>>>>>> And I think Jacek pointed out that the bindings references in this bindings
>>>>>>> don't even exist.
>>>>>>>
>>>>>>> I am thinking we need to deprecate this MFD driver and consolidate these drivers
>>>>>>> in the LED directory as we indicated before.  I did not find any ti-lmu support
>>>>>>> code.
>>>>>>>
>>>>>>> ti-lmu common core code and then the LED children appending the feature differentiation.
>>>>>>
>>>>>>> Need some maintainer weigh in here.
>>>>>>
>>>>>> Hehe. I'm maintnainer. Fun.
>>>>>
>>>>> I know.  I want to see if there was any other opinion.  Especially for the LED driver.
>>>>>
>>>> [...]
>>>>
>>>> I have a question - is this lm3697 LED controller a cell of some MFD
>>>> device? Or is it a self-contained chip?
>>>>
>>>
>>> This is a self contained chip.  And the LM3697 only function is a LED driver.
>>> It does not have any other special functions like the LM363X drivers for GPIO and Regulator support.
>>
>> This is an argument for merging it as a standalone LED class driver
>> then. It is even more justifiable, taking into account uncertainties
>> related to the proper way of adding the support for it to the existing
>> MFD driver, whereas the code reuse would be the only advantage of having
>> thus support in MFD subsystem.
>>
> 
> Does the argument carry over to the other devices?

If we want to be consequent - yes.

> Like the LM3632 (part of the ti-lmu) has flash and torch and no other special functions
> so it would look like the lm3601x family with different register mappings.

Yes, this is obvious candidate for LED class flash driver.

> The LM3631 seems to also be just a LED driver with no extra functionality
> 
> I could go buy an EVM and put together a driver for that device as well using the lm3601x as
> reference.

I'm not going to encourage you to make this expense, but to put it
politically - I'd happily welcome those drivers in the LED subsystem ;-)

-- 
Best regards,
Jacek Anaszewski