[PATCH 8/9] arm64: dts: allwinner: pinebook: Fix backlight regulator

Samuel Holland samuel at sholland.org
Sun Jan 19 08:31:03 PST 2020


The output from the backlight regulator is labeled as "VBKLT" in the
schematic. Using the equation and resistor values from the schematic,
the output is approximately 18V, not 3.3V. Since the regulator in use
(SS6640STR) is a boost regulator powered by PS (battery or AC input),
which are both >3.3V, the output could not be 3.3V anyway.

Signed-off-by: Samuel Holland <samuel at sholland.org>
---
 .../dts/allwinner/sun50i-a64-pinebook.dts     | 20 +++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts b/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts
index 3e762f93671a..96434fdeb5c0 100644
--- a/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts
+++ b/arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts
@@ -21,22 +21,13 @@
 		ethernet0 = &rtl8723cs;
 	};
 
-	vdd_bl: regulator at 0 {
-		compatible = "regulator-fixed";
-		regulator-name = "bl-3v3";
-		regulator-min-microvolt = <3300000>;
-		regulator-max-microvolt = <3300000>;
-		gpio = <&pio 7 6 GPIO_ACTIVE_HIGH>; /* PH6 */
-		enable-active-high;
-	};
-
 	backlight: backlight {
 		compatible = "pwm-backlight";
 		pwms = <&pwm 0 50000 0>;
 		brightness-levels = <0 5 10 15 20 30 40 55 70 85 100>;
 		default-brightness-level = <2>;
 		enable-gpios = <&pio 3 23 GPIO_ACTIVE_HIGH>; /* PD23 */
-		power-supply = <&vdd_bl>;
+		power-supply = <&reg_vbklt>;
 	};
 
 	chosen {
@@ -57,6 +48,15 @@
 		};
 	};
 
+	reg_vbklt: vbklt {
+		compatible = "regulator-fixed";
+		regulator-name = "vbklt";
+		regulator-min-microvolt = <18000000>;
+		regulator-max-microvolt = <18000000>;
+		gpio = <&pio 7 6 GPIO_ACTIVE_HIGH>; /* PH6 */
+		enable-active-high;
+	};
+
 	wifi_pwrseq: wifi_pwrseq {
 		compatible = "mmc-pwrseq-simple";
 		reset-gpios = <&r_pio 0 2 GPIO_ACTIVE_LOW>; /* PL2 */
-- 
2.23.0




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