Date: Sun, 17 Sep 2017 19:50:14 +0200
From: Pavel Machek <pavel@ucw.cz>
To: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: linux-input@vger.kernel.org, David Lin <dtwlin@google.com>,
        corbet@lwn.net, rpurdie@rpsys.net, hdegoede@redhat.com,
        gregkh@linuxfoundation.org, robh@kernel.org, romlem@google.com,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-leds@vger.kernel.org
Subject: Re: Vibrations in input vs. LED was Re: [PATCH v2 0/3] led:
 ledtrig-transient: add support for hrtimer
Message-ID: <20170917175013.GB13003@amd>
References: <20170913175400.42744-1-dtwlin@google.com>
 <20170913202032.GA30844@amd>
 <9c75c3a9-4123-c7f3-7725-45ba752d672a@gmail.com>
 <20170914205804.GA24339@amd>
 <ef3472a0-1e70-e64f-fe11-7fdfd768fc85@gmail.com>
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 <9afbd987-b237-24d4-e16a-ddd7fa70766a@gmail.com>
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Hi!

> >> Do you think such an improvement could be harmful in some way,
> >> even if it was made optional?
> >=20
> > Of course, we can make LED timing accurate down to microseconds. It will
> > mean increased overhead -- for "improvement" human can not perceive.
> >=20
> > If someone has problems with LED delays not being accurate enough... we
> > may want to fix it. But that is not the case here, is it?
>=20
> AFAIR David was mentioning that the hr_timer support is perceivable

He said that hr_timer support is perceivable _when he is driving
vibration motor_. Which he should not do in the first place.

Yes, if the difference is perceivable with LED in non-crazy
configuration (*), we can take the patch. Is it? Do we have someone
not from Google observing it?

									Pavel
(*) emulating PWM using blink trigger counts as "crazy" :-)


--=20
(english) http://www.livejournal.com/~pavelmachek
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