Commit 6c418328 authored by Fabio Estevam's avatar Fabio Estevam Committed by Shawn Guo
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ARM: dts: imx7d-sdb: Fix the SPI chipselect polarity 



The following warning is seen when the SPI GPIO driver probes:

gpio-expander@0 enforce active low on chipselect handle

The reason for this warning is clearly explained in the comments inside
drivers/gpio/gpiolib-of.c:

* SPI children have active low chip selects
* by default. This can be specified negatively
* by just omitting "spi-cs-high" in the
* device node, or actively by tagging on
* GPIO_ACTIVE_LOW as flag in the device
* tree. If the line is simultaneously
* tagged as active low in the device tree
* and has the "spi-cs-high" set, we get a
* conflict and the "spi-cs-high" flag will
* take precedence.

To properly represent the SPI chipselect polarity, change it to active-low
when the "spi-cs-high" property is absent.

Signed-off-by: default avatarFabio Estevam <festevam@gmail.com>
Signed-off-by: default avatarShawn Guo <shawnguo@kernel.org>
parent e40d0706

arch/arm/boot/dts/imx7d-sdb.dts

+1 −1
Original line number Diff line number Diff line
@@ -45,7 +45,7 @@ 
		pinctrl-0 = <&pinctrl_spi4>;

		gpio-sck = <&gpio1 13 GPIO_ACTIVE_HIGH>;

		gpio-mosi = <&gpio1 9 GPIO_ACTIVE_HIGH>;

		cs-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH>;

		cs-gpios = <&gpio1 12 GPIO_ACTIVE_LOW>;

		num-chipselects = <1>;

		#address-cells = <1>;

		#size-cells = <0>;