From: Daniel Thompson <daniel.thompson@linaro.org>
To: "Noralf Trønnes" <noralf@tronnes.org>
Cc: Marek Vasut <marex@denx.de>,
dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
Meghana Madhyastha <meghana.madhyastha@gmail.com>,
Sean Paul <seanpaul@chromium.org>,
Thierry Reding <treding@nvidia.com>
Subject: Re: [PATCH] video: backlight: Drop maximum brightness override for brightness zero
Date: Mon, 12 Jul 2021 11:25:53 +0100 [thread overview]
Message-ID: <20210712102553.ehsgp2ozrveuwaxv@maple.lan> (raw)
In-Reply-To: <0822c219-c1c6-0bb4-f379-e73f40adfa8e@tronnes.org>
On Fri, Jul 09, 2021 at 03:53:16PM +0200, Noralf Trønnes wrote:
>
>
> Den 09.07.2021 15.26, skrev Marek Vasut:
> > The note in c2adda27d202f ("video: backlight: Add of_find_backlight helper
> > in backlight.c") says that gpio-backlight uses brightness as power state.
> > This has been fixed since in ec665b756e6f7 ("backlight: gpio-backlight:
> > Correct initial power state handling") and other backlight drivers do not
> > require this workaround. Drop the workaround.
> >
> > This fixes the case where e.g. pwm-backlight can perfectly well be set to
> > brightness 0 on boot in DT, which without this patch leads to the display
> > brightness to be max instead of off.
> >
> > Fixes: c2adda27d202f ("video: backlight: Add of_find_backlight helper in backlight.c")
>
> I not sure about the rules, but if this is automatically picked up for
> stable, maybe this is needed to avoid changing behaviour on 4.19:
>
>
> of_find_backlight() was added in 4.17 and the gpio fix in 5.4.
>
> Or perhaps there are other ways to signal this dependency.
Agree we need to make sure the Fixes: tag doesn't provoke regressions
in v4.19.
Is this the syntax appropriate?
Cc: <stable@vger.kernel.org> # 5.4+
Cc: <stable@vger.kernel.org> # 4.19.x: ec665b756e6f7: backlight: gpio-backlight: Correct initial power state handling
> > Signed-off-by: Marek Vasut <marex@denx.de>
> > Cc: Daniel Thompson <daniel.thompson@linaro.org>
> > Cc: Meghana Madhyastha <meghana.madhyastha@gmail.com>
> > Cc: Noralf Trønnes <noralf@tronnes.org>
> > Cc: Sean Paul <seanpaul@chromium.org>
> > Cc: Thierry Reding <treding@nvidia.com>
> > ---
>
> Acked-by: Noralf Trønnes <noralf@tronnes.org>
With the above (or something similar to avoid problems with v4.19):
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Daniel.
prev parent reply other threads:[~2021-07-12 10:26 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-09 13:26 [PATCH] video: backlight: Drop maximum brightness override for brightness zero Marek Vasut
2021-07-09 13:53 ` Noralf Trønnes
2021-07-12 10:25 ` Daniel Thompson [this message]
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=20210712102553.ehsgp2ozrveuwaxv@maple.lan \
--to=daniel.thompson@linaro.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=linux-fbdev@vger.kernel.org \
--cc=marex@denx.de \
--cc=meghana.madhyastha@gmail.com \
--cc=noralf@tronnes.org \
--cc=seanpaul@chromium.org \
--cc=treding@nvidia.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).