From: Lee Jones <lee@kernel.org>
To: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
Cc: Daniel Thompson <daniel.thompson@linaro.org>,
Jingoo Han <jingoohan1@gmail.com>,
Thierry Reding <thierry.reding@gmail.com>,
Helge Deller <deller@gmx.de>,
linux-pwm@vger.kernel.org, dri-devel@lists.freedesktop.org,
linux-fbdev@vger.kernel.org, kernel@pengutronix.de
Subject: Re: [PATCH v2 1/2] backlight: pwm_bl: Configure pwm only once per backlight toggle
Date: Fri, 20 Jan 2023 17:07:06 +0000 [thread overview]
Message-ID: <Y8rKOozBnOGg2Sxg@google.com> (raw)
In-Reply-To: <20230120120018.161103-2-u.kleine-koenig@pengutronix.de>
On Fri, 20 Jan 2023, Uwe Kleine-König wrote:
> When the function pwm_backlight_update_status() was called with
> brightness > 0, pwm_get_state() was called twice (once directly and once
> in compute_duty_cycle). Also pwm_apply_state() was called twice (once in
> pwm_backlight_power_on() and once directly).
>
> Optimize this to do both calls only once.
>
> Note that with this affects the order of regulator and PWM setup. It's
> not expected to have a relevant effect on hardware. The rationale for
> this is that the regulator (and the GPIO) are reasonable to switch in
> pwm_backlight_power_on()/pwm_backlight_power_off() but the PWM has
> nothing to do with power. (The post_pwm_on_delay and pwm_off_delay are
> still there though.)
>
> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> ---
> drivers/video/backlight/pwm_bl.c | 28 ++++++++++------------------
> 1 file changed, 10 insertions(+), 18 deletions(-)
Applied, thanks
--
Lee Jones [李琼斯]
next prev parent reply other threads:[~2023-01-20 17:07 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-20 12:00 [PATCH v2 0/2] backlight: pwm_bl: Two PWM releated changes Uwe Kleine-König
2023-01-20 12:00 ` [PATCH v2 1/2] backlight: pwm_bl: Configure pwm only once per backlight toggle Uwe Kleine-König
2023-01-20 17:07 ` Lee Jones [this message]
2023-01-20 12:00 ` [PATCH v2 2/2] backlight: pwm_bl: Don't rely on a disabled PWM emiting inactive state Uwe Kleine-König
2023-01-20 15:04 ` Daniel Thompson
2023-01-20 17:07 ` Lee Jones
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=Y8rKOozBnOGg2Sxg@google.com \
--to=lee@kernel.org \
--cc=daniel.thompson@linaro.org \
--cc=deller@gmx.de \
--cc=dri-devel@lists.freedesktop.org \
--cc=jingoohan1@gmail.com \
--cc=kernel@pengutronix.de \
--cc=linux-fbdev@vger.kernel.org \
--cc=linux-pwm@vger.kernel.org \
--cc=thierry.reding@gmail.com \
--cc=u.kleine-koenig@pengutronix.de \
/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).