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[PATCH 2/2] arm64: dts: set the default i2c pin drive strength to 16mA

From Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Newsgroups linux.kernel
Subject [PATCH 2/2] arm64: dts: set the default i2c pin drive strength to 16mA
Date 2015-12-11 19:20 +0100
Message-ID <qEAsq-81R-23@gated-at.bofh.it> (permalink)
References <qEAsq-81R-13@gated-at.bofh.it>
Organization linux.* mail to news gateway

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2mA drive strength is not enough when we connect multiple i2c devices
on the bus with different pull up resistors.

This issue was detected when multiple i2c devices connected on the other side
of level shifters on Linaro sensor board. Maxing up to 16mA made i2c much stable.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 arch/arm64/boot/dts/qcom/msm8916-pins.dtsi | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/msm8916-pins.dtsi b/arch/arm64/boot/dts/qcom/msm8916-pins.dtsi
index 49ec55a..1991af7 100644
--- a/arch/arm64/boot/dts/qcom/msm8916-pins.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8916-pins.dtsi
@@ -272,7 +272,7 @@
 		};
 		pinconf {
 			pins = "gpio6", "gpio7";
-			drive-strength = <2>;
+			drive-strength = <16>;
 			bias-disable = <0>;
 		};
 	};
@@ -296,7 +296,7 @@
 		};
 		pinconf {
 			pins = "gpio14", "gpio15";
-			drive-strength = <2>;
+			drive-strength = <16>;
 			bias-disable = <0>;
 		};
 	};
@@ -320,7 +320,7 @@
 		};
 		pinconf {
 			pins = "gpio22", "gpio23";
-			drive-strength = <2>;
+			drive-strength = <16>;
 			bias-disable = <0>;
 		};
 	};
-- 
1.9.1

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[PATCH 0/2] arm64: dts: qcom: few i2c fixes Srinivas Kandagatla <srinivas.kandagatla@linaro.org> - 2015-12-11 19:20 +0100
  [PATCH 1/2] arm64: dts: fix the i2c aliasing to match to schematics. Srinivas Kandagatla <srinivas.kandagatla@linaro.org> - 2015-12-11 19:20 +0100
  [PATCH 2/2] arm64: dts: set the default i2c pin drive strength to 16mA Srinivas Kandagatla <srinivas.kandagatla@linaro.org> - 2015-12-11 19:20 +0100

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