From mboxrd@z Thu Jan 1 00:00:00 1970 From: Biwen Li Subject: [v6,3/3] arm64: dts: fsl-ls208xa-rdb: fix an errata E-00013 Date: Fri, 29 Nov 2019 17:22:22 +0800 Message-ID: <20191129092222.2706-3-biwen.li@nxp.com> References: <20191129092222.2706-1-biwen.li@nxp.com> Return-path: In-Reply-To: <20191129092222.2706-1-biwen.li@nxp.com> Sender: linux-kernel-owner@vger.kernel.org To: peda@axentia.se, leoyang.li@nxp.com, robh+dt@kernel.org, mark.rutland@arm.com Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Biwen Li List-Id: linux-i2c@vger.kernel.org Specify a channel zero in idle state to avoid enterring tri-stated state for PCA9547. About E-00013: - Description: I2C1 and I2C3 buses are missing pull-up. - Impact: When the PCA954x device is tri-stated, the I2C bus will float. This makes the I2C bus and its associated downstream devices inaccessible. - Hardware fix: Populate resistors R189 and R190 for I2C1 and resistors R228 and R229 for I2C3. - Software fix: Remove the tri-state option from the PCA954x driver(PCA954x always on enable status, specify a channel zero in dts to fix the errata E-00013). Signed-off-by: Biwen Li --- Change in v6: - none Change in v5: - specify a channel zero when pca9547 in idle state. arch/arm64/boot/dts/freescale/fsl-ls208xa-rdb.dtsi | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/boot/dts/freescale/fsl-ls208xa-rdb.dtsi b/arch/arm64/boot/dts/freescale/fsl-ls208xa-rdb.dtsi index 6fd7f63085c9..412f1bc0db5f 100644 --- a/arch/arm64/boot/dts/freescale/fsl-ls208xa-rdb.dtsi +++ b/arch/arm64/boot/dts/freescale/fsl-ls208xa-rdb.dtsi @@ -49,6 +49,7 @@ reg = <0x75>; #address-cells = <1>; #size-cells = <0>; + idle-state = <0>; i2c@1 { #address-cells = <1>; #size-cells = <0>; -- 2.17.1