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Re: [PATCH] Documentation: small fixes for LEDs, hide notes about vibration

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Hi!

> > -As a specific example of this use-case, let's look at vibrate feature on
> > -phones. Vibrate function on phones is implemented using PWM pins on SoC or
> > -PMIC. There is a need to activate one shot timer to control the vibrate
> > -feature, to prevent user space crashes leaving the phone in vibrate mode
> > -permanently causing the battery to drain.
> 
> I'm not sure if it is a good idea to remove this description. Users will
> still be able to use transient trigger this way. It has been around for
> five years already and there are users which employ it in this
> particular way [0].

I am. Yes, people were doing that, but no, vibration motor is not a
LED. PWM behaviour is different, for example, motor is likely to stop
at low PWM values. We do not want people to do that.

> Apart from that it's the only documented kernel API for vibrate devices
> AFAICT.

Input subsystem has force-feedback protocol, which is very often just
vibrations. Documentation/input/ff.rst . Nokia N900 phone actually
uses that API.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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[PATCH] Documentation: small fixes for LEDs, hide notes about  vibration Pavel Machek <pavel@ucw.cz> - 2017-08-28 12:00 +0200
  Re: [PATCH] Documentation: small fixes for LEDs, hide notes about  vibration Jacek Anaszewski <jacek.anaszewski@gmail.com> - 2017-08-29 21:50 +0200
    Re: [PATCH] Documentation: small fixes for LEDs, hide notes about  vibration Pavel Machek <pavel@ucw.cz> - 2017-08-29 22:40 +0200
      Re: [PATCH] Documentation: small fixes for LEDs, hide notes about  vibration Jacek Anaszewski <jacek.anaszewski@gmail.com> - 2017-08-30 22:50 +0200
        Re: [PATCH] Documentation: small fixes for LEDs, hide notes about  vibration Pavel Machek <pavel@ucw.cz> - 2017-08-31 10:10 +0200
          Re: [PATCH] Documentation: small fixes for LEDs, hide notes about  vibration Jacek Anaszewski <jacek.anaszewski@gmail.com> - 2017-08-31 22:20 +0200
            Re: [PATCH] Documentation: small fixes for LEDs, hide notes about vibration Rob Herring <robh+dt@kernel.org> - 2017-09-01 00:30 +0200
      Re: [PATCH] Documentation: small fixes for LEDs, hide notes about vibration Jani Nikula <jani.nikula@linux.intel.com> - 2017-08-31 10:00 +0200
        Re: [PATCH] Documentation: small fixes for LEDs, hide notes about  vibration Pavel Machek <pavel@ucw.cz> - 2017-08-31 10:10 +0200

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