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* [PATCH 0/2] arm64: dts: qcom: few i2c fixes
@ 2015-12-11 18:11 Srinivas Kandagatla
  2015-12-11 18:12 ` [PATCH 1/2] arm64: dts: fix the i2c aliasing to match to schematics Srinivas Kandagatla
  2015-12-11 18:13 ` [PATCH 2/2] arm64: dts: set the default i2c pin drive strength to 16mA Srinivas Kandagatla
  0 siblings, 2 replies; 3+ messages in thread
From: Srinivas Kandagatla @ 2015-12-11 18:11 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Andy, 

Here are two i2c dt fixes which I have been using for long time on Landing team tree.

Can you please consider fixes for v4.5.

Thanks,
srini

Srinivas Kandagatla (2):
  arm64: dts: fix the i2c aliasing to match to schematics.
  arm64: dts: set the default i2c pin drive strength to 16mA

 arch/arm64/boot/dts/qcom/apq8016-sbc.dtsi  | 3 +++
 arch/arm64/boot/dts/qcom/msm8916-pins.dtsi | 6 +++---
 2 files changed, 6 insertions(+), 3 deletions(-)

-- 
1.9.1

^ permalink raw reply	[flat|nested] 3+ messages in thread

* [PATCH 1/2] arm64: dts: fix the i2c aliasing to match to schematics.
  2015-12-11 18:11 [PATCH 0/2] arm64: dts: qcom: few i2c fixes Srinivas Kandagatla
@ 2015-12-11 18:12 ` Srinivas Kandagatla
  2015-12-11 18:13 ` [PATCH 2/2] arm64: dts: set the default i2c pin drive strength to 16mA Srinivas Kandagatla
  1 sibling, 0 replies; 3+ messages in thread
From: Srinivas Kandagatla @ 2015-12-11 18:12 UTC (permalink / raw)
  To: linux-arm-kernel

This patch fixes the i2c bus number aliasing so that it matches with the
schematics bus naming.

Without this patch the user might would get bus numbers depending on
the order the devices are probed.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 arch/arm64/boot/dts/qcom/apq8016-sbc.dtsi | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/apq8016-sbc.dtsi b/arch/arm64/boot/dts/qcom/apq8016-sbc.dtsi
index 6b8abbe..6f19956 100644
--- a/arch/arm64/boot/dts/qcom/apq8016-sbc.dtsi
+++ b/arch/arm64/boot/dts/qcom/apq8016-sbc.dtsi
@@ -20,6 +20,9 @@
 	aliases {
 		serial0 = &blsp1_uart2;
 		serial1 = &blsp1_uart1;
+		i2c0	= &blsp_i2c2;
+		i2c1	= &blsp_i2c6;
+		i2c3	= &blsp_i2c4;
 	};
 
 	chosen {
-- 
1.9.1

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH 2/2] arm64: dts: set the default i2c pin drive strength to 16mA
  2015-12-11 18:11 [PATCH 0/2] arm64: dts: qcom: few i2c fixes Srinivas Kandagatla
  2015-12-11 18:12 ` [PATCH 1/2] arm64: dts: fix the i2c aliasing to match to schematics Srinivas Kandagatla
@ 2015-12-11 18:13 ` Srinivas Kandagatla
  1 sibling, 0 replies; 3+ messages in thread
From: Srinivas Kandagatla @ 2015-12-11 18:13 UTC (permalink / raw)
  To: linux-arm-kernel

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

^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2015-12-11 18:13 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2015-12-11 18:11 [PATCH 0/2] arm64: dts: qcom: few i2c fixes Srinivas Kandagatla
2015-12-11 18:12 ` [PATCH 1/2] arm64: dts: fix the i2c aliasing to match to schematics Srinivas Kandagatla
2015-12-11 18:13 ` [PATCH 2/2] arm64: dts: set the default i2c pin drive strength to 16mA Srinivas Kandagatla

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