linux-leds.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Pavel Machek <pavel@ucw.cz>
To: Ezequiel Garcia <ezequiel@collabora.com>
Cc: kernel list <linux-kernel@vger.kernel.org>,
	linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
	linux-omap@vger.kernel.org, tony@atomide.com, sre@kernel.org,
	nekit1000@gmail.com, mpartap@gmx.net, merlijn@wizzup.org,
	jacek.anaszewski@gmail.com, 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
Date: Mon, 22 Jul 2019 09:50:32 +0200	[thread overview]
Message-ID: <20190722075032.GA27524@amd> (raw)
In-Reply-To: <22d7eca4ad8aa2e73933c4f83c92221ce6e0945a.camel@collabora.com>

[-- Attachment #1: Type: text/plain, Size: 1154 bytes --]

Hi!

> > Configuring backlight trigger from dts results in backlight off during
> > boot. Machine looks dead upon boot, which is not good.
> > 
> > Fix that by enabling LED on trigger activation.

> > +++ b/drivers/leds/trigger/ledtrig-backlight.c
> > @@ -114,6 +114,8 @@ static int bl_trig_activate(struct led_classdev *led)
> >  	n->old_status = UNBLANK;
> >  	n->notifier.notifier_call = fb_notifier_callback;
> >  
> > +	led_set_brightness(led, LED_ON);
> > +
> 
> This looks fishy.
> 
> Maybe you should use a default-state = "keep" instead? (and you'll have
> to support it in the LED driver).
> 
> That'll give you proper "don't touch the LED if it was turned on" behavior,
> which is what you seem to want.

Actually no, that's not what I want. LED should go on if the display
is active, as soon as trigger is activated.

Unfortunately, I have see no good way to tell if the display is
active (and display is usually active when trigger is activated).

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

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]

  reply	other threads:[~2019-07-22  7:50 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-18 19:08 [PATCH] Enable backlight when trigger is activated Pavel Machek
2019-07-21 23:00 ` Ezequiel Garcia
2019-07-22  7:50   ` Pavel Machek [this message]
2019-07-22 20:25     ` Jacek Anaszewski
2019-07-22 21:04       ` Pavel Machek
2019-07-24  8:33       ` Pavel Machek
2019-07-24 21:16         ` Jacek Anaszewski

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190722075032.GA27524@amd \
    --to=pavel@ucw.cz \
    --cc=b.zolnierkie@samsung.com \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=ezequiel@collabora.com \
    --cc=jacek.anaszewski@gmail.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-fbdev@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-leds@vger.kernel.org \
    --cc=linux-omap@vger.kernel.org \
    --cc=merlijn@wizzup.org \
    --cc=mpartap@gmx.net \
    --cc=nekit1000@gmail.com \
    --cc=sre@kernel.org \
    --cc=tony@atomide.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).