From: Daniel Thompson <daniel.thompson@linaro.org>
To: Enric Balletbo Serra <eballetbo@gmail.com>
Cc: Enric Balletbo i Serra <enric.balletbo@collabora.com>,
Doug Anderson <dianders@google.com>, Pavel Machek <pavel@ucw.cz>,
Rob Herring <robh+dt@kernel.org>,
Jingoo Han <jingoohan1@gmail.com>,
Richard Purdie <rpurdie@rpsys.net>,
Jacek Anaszewski <jacek.anaszewski@gmail.com>,
Brian Norris <briannorris@google.com>,
Guenter Roeck <groeck@google.com>,
Lee Jones <lee.jones@linaro.org>,
Alexandru Stan <amstan@google.com>,
linux-leds@vger.kernel.org,
"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
linux-kernel <linux-kernel@vger.kernel.org>,
kernel@collabora.com
Subject: Re: [PATCH v3 0/4] backlight: pwm_bl: support linear interpolation and brightness to human eye
Date: Tue, 20 Mar 2018 19:22:12 +0800 [thread overview]
Message-ID: <20180320112212.2mwthxug3pu7uqgg@holly.lan> (raw)
In-Reply-To: <CAFqH_52bXq76TnQLfnD0mohgr0d5iAcrHBcPefwnRB8gdbaYFQ@mail.gmail.com>
On Mon, Mar 19, 2018 at 05:04:31PM +0100, Enric Balletbo Serra wrote:
> Hi Daniel,
>
> Gentle ping for this series, there is any possibility you have a
> chance to review it? Let me know if you want I change something.
I haven't got it in my TODO backlog... which means either I mistakenly
deleted it when it went through originally or that I deliberately deleted
it because I thought a v4 was coming along soon.
I could go diving through the archives if I need to but were there other
pending changes for this patchset?
Daniel.
>
> Thanks,
> Enric
>
> 2018-02-08 12:30 GMT+01:00 Enric Balletbo i Serra
> <enric.balletbo@collabora.com>:
> > Dear all,
> >
> > This series is a third patchset integrating the requested changes.
> >
> > The first and second patch what tries to solve is the problem of
> > granularity for high resolution PWMs. The idea is simple interpolate
> > between 2 brightness values so we can have a high PWM duty cycle (a
> > 16 bits PWM is up to 65535 possible steps) without having to list
> > out every possible value in the dts. I think that this patch is
> > required to not break backward compability, to be more flexible and
> > also extend the functionality to be able to use high resolution PWM
> > with enough steps to have a good UI experience in userspace.
> >
> > The thirth and fourth patch is a bit more ambicious, the idea is let
> > decide the driver the brightness-levels required in function of the PWM
> > resolution. To do this create a brightness-levels table filled with the
> > CIE 1931 algorithm values to convert brightness to PWM duty cycle.
> >
> > More detailed info is available in the commit message of every patch.
> >
> > Both functionalities were tested on a Samsung Chromebook Plus (that has
> > a 16 bits PWM) and a SL50 device (with a 8 bits PWM)
> >
> > Waiting for your feedback.
> >
> > Best regards,
> >
> > Enric Balletbo i Serra (4):
> > backlight: pwm_bl: linear interpolation between brightness-levels
> > dt-bindings: pwm-backlight: add a num-interpolation-steps property.
> > backlight: pwm_bl: compute brightness of LED linearly to human eye.
> > dt-bindings: pwm-backlight: move brightness-levels to optional.
> >
> > .../bindings/leds/backlight/pwm-backlight.txt | 34 ++-
> > drivers/video/backlight/pwm_bl.c | 232 +++++++++++++++++++--
> > 2 files changed, 246 insertions(+), 20 deletions(-)
> >
> > --
> > 2.15.1
> >
next prev parent reply other threads:[~2018-03-20 11:22 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-08 11:30 [PATCH v3 0/4] backlight: pwm_bl: support linear interpolation and brightness to human eye Enric Balletbo i Serra
2018-02-08 11:30 ` [PATCH v3 1/4] backlight: pwm_bl: linear interpolation between brightness-levels Enric Balletbo i Serra
2018-04-06 15:46 ` Daniel Thompson
2018-02-08 11:30 ` [PATCH v3 2/4] dt-bindings: pwm-backlight: add a num-interpolation-steps property Enric Balletbo i Serra
2018-02-18 22:49 ` Rob Herring
2018-02-08 11:30 ` [PATCH v3 3/4] backlight: pwm_bl: compute brightness of LED linearly to human eye Enric Balletbo i Serra
2018-04-06 15:51 ` Daniel Thompson
2019-06-07 22:19 ` Matthias Kaehlcke
2019-06-08 21:02 ` Pavel Machek
2019-06-10 10:00 ` Enric Balletbo i Serra
2019-06-10 20:39 ` Matthias Kaehlcke
2019-06-10 21:02 ` Enric Balletbo i Serra
2019-06-10 21:54 ` Matthias Kaehlcke
2019-06-10 20:52 ` Matthias Kaehlcke
2019-06-11 10:49 ` Daniel Thompson
2019-06-11 16:55 ` Brian Norris
2019-06-11 22:30 ` Matthias Kaehlcke
2019-06-12 9:54 ` Pavel Machek
2019-06-12 11:03 ` Daniel Thompson
2019-06-12 19:26 ` Matthias Kaehlcke
2019-06-12 19:47 ` Daniel Thompson
2019-06-12 21:59 ` Matthias Kaehlcke
2019-06-17 13:01 ` Pavel Machek
2019-06-17 20:03 ` Matthias Kaehlcke
2018-02-08 11:30 ` [PATCH v3 4/4] dt-bindings: pwm-backlight: move brightness-levels to optional Enric Balletbo i Serra
2018-03-19 16:04 ` [PATCH v3 0/4] backlight: pwm_bl: support linear interpolation and brightness to human eye Enric Balletbo Serra
2018-03-20 11:22 ` Daniel Thompson [this message]
2018-03-20 12:13 ` Enric Balletbo Serra
2018-04-06 15:54 ` Daniel Thompson
2018-04-09 8:17 ` Lee Jones
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