Re: Vibrations in input vs. LED was Re: [PATCH v2 0/3] led: ledtrig-transient: add support for hrtimer

From: Jacek Anaszewski
Date: Wed Sep 20 2017 - 16:09:45 EST


On 09/20/2017 01:29 PM, Pavel Machek wrote:
>>>>> I'd leave the decision to the user. We could add a note to the
>>>>> Documentation/leds/ledtrig-transient.txt that force feedback interface
>>>>> should be preferable choice for driving vibrate devices.
>>>>> However only if following conditions are met:
>>>>
>>>> What I meant is that it is my decision, as a LED subsystem maintainer,
>>>> to accept the addition of a note about some other subsystem offering
>>>> an equivalent or even better substitute of the feature being available
>>>> in the subsystem I am responsible for. And I will accept such a patch
>>>> only if mentioned conditions are met.
>>>
>>> Having the wording in documentation does not in any way stops Android
>>> folks from continuing [ab]using the transient trigger. But this is
>>> their choice. The purpose of documentation is to document the best
>>> practices, not all possible crazy solutions one can come up with.
>>
>> Yes. but if the information has been in place for years, we can't
>> just remove it without giving an instruction on how to use the
>> substitute.
>
> I gave you information how to use the substitute.

That information was quite vague. I'd like to see a sample application
in tools/input.

> I already suggested patch to documentation. If you do the same, maybe
> we can agree on documentation update.

Your patch was just removing few lines of documentation. I'd expect more
empathic approach to the current users, i.e.:

- pointer to the sample application in tools/input showing how to
setup gpio driven vibrate device with use of ff interface with
1kHz vibration frequency.


--
Best regards,
Jacek Anaszewski