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From:   Alexandru Stan <amstan@chromium.org>
To:     Heiko Stuebner <heiko@sntech.de>, Rob Herring <robh+dt@kernel.org>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Thierry Reding <thierry.reding@gmail.com>,
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        <u.kleine-koenig@pengutronix.de>, Lee Jones <lee.jones@linaro.org>,
        Daniel Thompson <daniel.thompson@linaro.org>,
        Jingoo Han <jingoohan1@gmail.com>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc:     Douglas Anderson <dianders@chromium.org>,
        Matthias Kaehlcke <mka@chromium.org>,
        Enric Balletbo i Serra <enric.balletbo@collabora.com>,
        Alexandru Stan <amstan@chromium.org>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org
Subject: [PATCH v3 1/3] ARM: dts: rockchip: veyron: Remove 0 point from brightness-levels
Date:   Wed, 21 Oct 2020 22:04:43 -0700
Message-Id: <20201021220404.v3.1.I96b8d872ec51171f19274e43e96cadc092881271@changeid>
In-Reply-To: <20201022050445.930403-1-amstan@chromium.org>
References: <20201022050445.930403-1-amstan@chromium.org>
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The extra 0 only adds one point in the userspace visible range,
so this change is almost a noop with the current driver behavior.

We don't need the 0% point, userspace seems to handle this just fine
because it uses the bl_power property to turn off the display.

Furthermore after adding "backlight: pwm_bl: Fix interpolation" patch,
the backlight interpolation will work a little differently. So we need
to preemptively remove the 0-3 segment since otherwise we would have a
252 long interpolation that would slowly go between 0 and 3, looking
really bad in userspace. So it's almost a noop/cleanup now, but it will
be required in the future.

Signed-off-by: Alexandru Stan <amstan@chromium.org>
---

 arch/arm/boot/dts/rk3288-veyron-jaq.dts    | 2 +-
 arch/arm/boot/dts/rk3288-veyron-minnie.dts | 2 +-
 arch/arm/boot/dts/rk3288-veyron-tiger.dts  | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm/boot/dts/rk3288-veyron-jaq.dts b/arch/arm/boot/dts/rk3288-veyron-jaq.dts
index af77ab20586d..4a148cf1defc 100644
--- a/arch/arm/boot/dts/rk3288-veyron-jaq.dts
+++ b/arch/arm/boot/dts/rk3288-veyron-jaq.dts
@@ -20,7 +20,7 @@ / {
 
 &backlight {
 	/* Jaq panel PWM must be >= 3%, so start non-zero brightness at 8 */
-	brightness-levels = <0 8 255>;
+	brightness-levels = <8 255>;
 	num-interpolated-steps = <247>;
 };
 
diff --git a/arch/arm/boot/dts/rk3288-veyron-minnie.dts b/arch/arm/boot/dts/rk3288-veyron-minnie.dts
index f8b69e0a16a0..82fc6fba9999 100644
--- a/arch/arm/boot/dts/rk3288-veyron-minnie.dts
+++ b/arch/arm/boot/dts/rk3288-veyron-minnie.dts
@@ -39,7 +39,7 @@ volum_up {
 
 &backlight {
 	/* Minnie panel PWM must be >= 1%, so start non-zero brightness at 3 */
-	brightness-levels = <0 3 255>;
+	brightness-levels = <3 255>;
 	num-interpolated-steps = <252>;
 };
 
diff --git a/arch/arm/boot/dts/rk3288-veyron-tiger.dts b/arch/arm/boot/dts/rk3288-veyron-tiger.dts
index 069f0c2c1fdf..52a84cbe7a90 100644
--- a/arch/arm/boot/dts/rk3288-veyron-tiger.dts
+++ b/arch/arm/boot/dts/rk3288-veyron-tiger.dts
@@ -23,7 +23,7 @@ / {
 
 &backlight {
 	/* Tiger panel PWM must be >= 1%, so start non-zero brightness at 3 */
-	brightness-levels = <0 3 255>;
+	brightness-levels = <3 255>;
 	num-interpolated-steps = <252>;
 };
 
-- 
2.28.0