[PATCH 3/4] ARM: dts: imx6qdl-tqma6: Fix the SPI chipselect polarity

The conversion of the spi-imx driver to use GPIO descriptors
in commit 8cdcd8aeee28 ("spi: imx/fsl-lpspi: Convert to GPIO descriptors")
helped to detect the following SPI chipselect polarity mismatch on an
imx6q-sabresd for example:
    
[    4.854337] m25p80@0 enforce active low on chipselect handle
   
Prior to the above commit, the chipselect polarity passed via cs-gpios
property was ignored and considered active-low.
    
The reason for such mismatch 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: Fabio Estevam <festevam@gmail.com>
---
 arch/arm/boot/dts/imx6qdl-tqma6.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/imx6qdl-tqma6.dtsi b/arch/arm/boot/dts/imx6qdl-tqma6.dtsi
index b18b83ac6aee..51a3a5392c95 100644
--- a/arch/arm/boot/dts/imx6qdl-tqma6.dtsi
+++ b/arch/arm/boot/dts/imx6qdl-tqma6.dtsi

@@ -20,7 +20,7 @@ reg_3p3v: regulator-3p3v {
 &ecspi1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_ecspi1>;
-	cs-gpios = <&gpio3 19 GPIO_ACTIVE_HIGH>;
+	cs-gpios = <&gpio3 19 GPIO_ACTIVE_LOW>;
 	status = "okay";
 
 	m25p80: flash@0 {

-- 
2.25.1


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