On Mon, 21 Nov 2022 15:18:32 -0300
Fabio Estevam [off-list ref] wrote:

[Adding Angus and David]

Thanks. This was apparently necessary ;-)

On Mon, Nov 21, 2022 at 3:12 PM Quentin Schulz [off-list ref] wrote:

quoted

From: Quentin Schulz <redacted>

The reset line is active low for the Goodix touchscreen controller so
let's fix the polarity in the Device Tree node.

Signed-off-by: Quentin Schulz <redacted>
---
 arch/arm64/boot/dts/freescale/imx8mm-prt8mm.dts         | 2 +-
 arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8mm-prt8mm.dts b/arch/arm64/boot/dts/freescale/imx8mm-prt8mm.dts
index 9fbbbb556c0b3..df7e5ae9698e1 100644
--- a/arch/arm64/boot/dts/freescale/imx8mm-prt8mm.dts
+++ b/arch/arm64/boot/dts/freescale/imx8mm-prt8mm.dts

@@ -107,7 +107,7 @@ touchscreeen@5d {
                interrupt-parent = <&gpio1>;
                interrupts = <8 IRQ_TYPE_NONE>;
                irq-gpios = <&gpio1 8 GPIO_ACTIVE_HIGH>;
-               reset-gpios = <&gpio1 9 GPIO_ACTIVE_HIGH>;
+               reset-gpios = <&gpio1 9 GPIO_ACTIVE_LOW>;

NACK!

The PRT8MM has an inverter in the reset line. The reason for that is that the
reset line needs to be inactive when the driving side is unpowered.
The DT was correct, this change will break it.

quoted

        };

        temp-sense@70 {

diff --git a/arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts b/arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts
index 6445c6b90b5bb..b038300812b1e 100644
--- a/arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts
+++ b/arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts

@@ -542,7 +542,7 @@ touchscreen@5d {
                pinctrl-0 = <&pinctrl_ts>;
                interrupt-parent = <&gpio3>;
                interrupts = <0 IRQ_TYPE_LEVEL_LOW>;
-               reset-gpios = <&gpio1 5 GPIO_ACTIVE_HIGH>;
+               reset-gpios = <&gpio1 5 GPIO_ACTIVE_LOW>;
                irq-gpios = <&gpio3 0 GPIO_ACTIVE_HIGH>;
                touchscreen-size-x = <720>;
                touchscreen-size-y = <1440>;

--

b4 0.10.1  

Best regards,

-- 
David Jander
Protonic Holland.

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