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

Jacek Anaszewski
2017-10-06T20:57:45Z

On 10/06/2017 01:48 PM, Pavel Machek wrote:
> On Wed 2017-09-20 22:08:42, Jacek Anaszewski wrote:
>> 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.
>
> So please write it.

This is my demand as a reviewer. I've already laid out the conditions
under which I'll accept the patch. It seems that you're proficient
in the subject enough to cope with this task.

>>> 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.
>
> Yes, my patch is removing dangerously misleading documentation about
> LED subsystem.

It's neither dangerous nor misleading.

> Please apply it.

Right after I'll get the patch with the tool showing how to use
input subsystem to achieve the same effect as with use of
ledtrig-transient.

--
Best regards,
Jacek Anaszewski