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Date:   Mon, 22 Jul 2019 23:04:07 +0200
From:   Pavel Machek <pavel@ucw.cz>
To:     Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc:     Ezequiel Garcia <ezequiel@collabora.com>,
        kernel list <linux-kernel@vger.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
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        nekit1000@gmail.com, mpartap@gmx.net, merlijn@wizzup.org,
        linux-leds@vger.kernel.org, b.zolnierkie@samsung.com,
        dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org
Subject: Re: [PATCH] Enable backlight when trigger is activated
Message-ID: <20190722210407.GA25617@amd>
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Hi!

> >> This looks fishy.
> >>
> >> Maybe you should use a default-state =3D "keep" instead? (and you'll h=
ave
> >> to support it in the LED driver).
> >>
> >> That'll give you proper "don't touch the LED if it was turned on" beha=
vior,
> >> which is what you seem to want.
> >=20
> > Actually no, that's not what I want. LED should go on if the display
> > is active, as soon as trigger is activated.
> >=20
> > Unfortunately, I have see no good way to tell if the display is
> > active (and display is usually active when trigger is activated).
>=20
> default-state DT property can be also set to "on"
> (see Documentation/devicetree/bindings/leds/common.txt).

Ok, thanks for the hint, that could work. (I thought we were using
default trigger to set the LED "on").

Now...this gives me option of 0% or 100% brightness, while best would
be 10% brightness.... but I guess we can live with that ;-).

									Pavel
--=20
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo=
g.html

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