From: Pavel Machek <pavel@ucw.cz>
To: Paulo Costa <me@paulo.costa.nom.br>
Cc: linux-leds@vger.kernel.org
Subject: Re: [RFC] ledtrig-dither: A Poor man's adjustable LED brightness.
Date: Mon, 28 Aug 2017 11:10:33 +0200 [thread overview]
Message-ID: <20170828091033.GB25025@amd> (raw)
In-Reply-To: <CADbEYbkGYO7dSuMcK4SjtWch+2GjPL7axPuk7UHohWLCfkj61Q@mail.gmail.com>
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On Thu 2017-08-17 01:21:37, Paulo Costa wrote:
> > Hmm. You could do led=on, udelay(100), led=off. Do that 100 times a
> > second, and I believe you'll get quite nice low levels.
>
> I don't want to keep the CPU busy on a delay() just for blinking led,
> even if only for a few micros.
Well... it will enable you to have nice low brigtness. Few
microseconds should not be a problem.
> > Now... nice hack. Probably can be improved. But is it suitable for
> > mainline?
>
> Thank you =)
>
> It's a proof of concept for now, definitely not ready for mainline.
>
> Instead of a LED trigger + wrapper LED entry, I think this should kick in
> if we set 'myled/dither=1' or something like that.
>
> Now, do you think it would be a nice addition / Should I put more work on it?
Actually, I'm not sure. Sounds a bit too hacky to me... Your
choice. If your goal is to learn about kernel, you are on the right
track :-).
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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prev parent reply other threads:[~2017-08-28 9:10 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-15 21:35 [RFC] ledtrig-dither: A Poor man's adjustable LED brightness Paulo Costa
2017-08-15 22:34 ` Pavel Machek
2017-08-16 3:55 ` Paulo Costa
2017-08-16 22:30 ` Pavel Machek
2017-08-17 4:21 ` Paulo Costa
2017-08-28 9:10 ` Pavel Machek [this message]
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