From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pavel Machek <pavel@ucw.cz>
Subject: Re: Disk activity trigger: keeps blinking under full load
Date: Sun, 26 May 2019 10:18:06 +0200
Message-ID: <20190526081806.GA16279@amd>
References: <20190523214301.GA14788@amd>
 <67fee5a8-cba1-79aa-104c-84bbe0e168e9@gmail.com>
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To: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org, linus.walleij@linaro.org, linz@li-pro.net, rpurdie@rpsys.net
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On Sat 2019-05-25 19:02:47, Jacek Anaszewski wrote:
> Hi,
>=20
> On 5/23/19 11:43 PM, Pavel Machek wrote:
> >Hi!
> >
> >I'm trying to use disk activity trigger on a scrollock LED... but it
> >significantly differs from "usual" disk LED: even under "full" disk
> >activity (linear read) where it should be solidly "on", it keeps
> >blinking.
> >
> >I guess that's what led_trigger_blink_oneshot() does. I tried to
> >change the parameters... off_delay =3D=3D 0 breaks it completely, and ev=
en
> >with delay of 1 it behaves very weirdly.
> >
> >Is there better helper I should use?
>=20
> It seems this is the way how led_blink_set_oneshot() works.
> It initially checks whether timer is pending and doesn't
> reset the timer in this case:
>=20
>         if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
>              timer_pending(&led_cdev->blink_timer))
>                 return;
>=20
> In effect you get gaps between timer expiration and setting of a new
> blink shot.

Yep. I consider it a bug (it differs from hardware disk activity LEDs
and looks horrible).

Is there someone who considers it a feature?
								Pavel
							=09
--=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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