From: Aaron Lu <aaron.lu@intel.com>
To: Valdis.Kletnieks@vt.edu
Cc: "Rafael J. Wysocki" <rafael@kernel.org>,
"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
Len Brown <lenb@kernel.org>
Subject: Re: linux-next 20160512 - ACPI issue with screen brightness
Date: Fri, 20 May 2016 15:17:20 +0800 [thread overview]
Message-ID: <20160520071720.GA30152@aaronlu.sh.intel.com> (raw)
In-Reply-To: <2897.1463727728@turing-police.cc.vt.edu>
On Fri, May 20, 2016 at 03:02:08AM -0400, Valdis.Kletnieks@vt.edu wrote:
> On Fri, 20 May 2016 13:45:30 +0800, Aaron Lu said:
> > On 05/20/2016 11:05 AM, Valdis.Kletnieks@vt.edu wrote:
> > > On Thu, 19 May 2016 18:53:17 -0400, Valdis.Kletnieks@vt.edu said:
> > >
> > >>>> next-20160512 sets the screen brightness to about 40%-ish or so, rather
> > >>>> than the 100% intensity I want.
> >
> > Do you mean after boot, the screen brightness is now 40% instead of the
> > previous 100%? Are you using a GUI?
>
> Nope, even the very first line of output from initramfs is dim, and if I then
> reboot and go into the BIOS settings, the screen intensity is at 40%. While
> it's rebooting, the Dell bios splash will start off bright and then suddenly
> dim down.
>
> With the patches reverted:
>
> [/sys/class/backlight/acpi_video0] grep . *bright*
> actual_brightness:95
> brightness:95
> max_brightness:95
>
> And the weird part inside the kernel - on a kernel that has the problem,
> /sys/class/backlight is *empty* - only '.' and '..' entries.
>
> No, I don't understand why the acpi_video0 entry isn't created when that
> commit is in place.
The commit probably makes acpi_video_init_brightness bail out for some
reason, adding debug prints under those "if (result)" in
acpi_video_init_brightness should help to identify where it goes wrong.
And your acpidump please, thanks.
next prev parent reply other threads:[~2016-05-20 7:17 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-17 18:41 linux-next 20160512 - ACPI issue with screen brightness Valdis Kletnieks
2016-05-17 20:50 ` Rafael J. Wysocki
2016-05-19 22:53 ` Valdis.Kletnieks
2016-05-20 3:05 ` Valdis.Kletnieks
2016-05-20 3:05 ` Valdis.Kletnieks
2016-05-20 5:45 ` Aaron Lu
2016-05-20 7:02 ` Valdis.Kletnieks
2016-05-20 7:17 ` Aaron Lu [this message]
2016-05-20 7:35 ` Aaron Lu
2016-05-21 0:15 ` Valdis.Kletnieks
2016-05-21 3:29 ` Aaron Lu
2016-05-21 7:55 ` [PATCH] ACPI / Thermal / video: fix max_level incorrect value Aaron Lu
2016-05-25 5:15 ` Aaron Lu
2016-05-26 1:49 ` Valdis.Kletnieks
2016-05-26 5:15 ` Aaron Lu
2016-05-27 0:42 ` Zhang, Rui
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=20160520071720.GA30152@aaronlu.sh.intel.com \
--to=aaron.lu@intel.com \
--cc=Valdis.Kletnieks@vt.edu \
--cc=lenb@kernel.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=rafael.j.wysocki@intel.com \
--cc=rafael@kernel.org \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.