[v6,3/3] arm64: dts: fsl-ls208xa-rdb: fix an errata E-00013

Biwen Li
2019-11-29T09:22:56Z

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 <biwen.li@nxp.com>
---
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