Usage of GPIO matrix keypad

[enginlee]

Hi,

I am trying to use Linux GPIO matrix keypad driver with my custom NUC980 board.
CONFIG_KEYBOARD_MATRIX has been enabled.
But I don't know how to configure row & column GPIOs.
I followed this document: https://www.kernel.org/doc/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt
Here is my device tree:
matrix_keypad: matrix-keypad@0 { compatible = "gpio-matrix-keypad"; col-gpios = < &gpio 0x46 GPIO_ACTIVE_LOW /* PC6~PC10 as output */ &gpio 0x47 GPIO_ACTIVE_LOW &gpio 0x48 GPIO_ACTIVE_LOW &gpio 0x49 GPIO_ACTIVE_LOW &gpio 0x4A GPIO_ACTIVE_LOW >; row-gpios = < &gpio 0xA0 GPIO_ACTIVE_LOW /* PF0~PF3 as input */ &gpio 0xA1 GPIO_ACTIVE_LOW &gpio 0xA2 GPIO_ACTIVE_LOW &gpio 0xA3 GPIO_ACTIVE_LOW >;
But I got an error when compile DTS file:
syntax error FATAL ERROR: Unable to parse input tree
How do I reference NUC980 GPIOs in device tree?

Thanks,

-Engin

[yachen]

dts compiler should report the line that contains syntax error?

[enginlee]

Yes, there is an error for parsing "&gpio"
Error: arch/arm/boot/dts/nuc980-climax-ddr64m-nor32m-kp.dts:442.17-18 syntax error FATAL ERROR: Unable to parse input tree scripts/Makefile.lib:293: recipe for target 'arch/arm/boot/dts/nuc980-climax-ddr64m-nor32m-kp.dtb' failed
Please check the attachment for the full DTS file
keypad_dts.txt

Thank you

[yachen]

The problem is not caused by &gpio. It's because of the undefined GPIO_ACTIVE_LOW.

[enginlee]

Yes, you are right.
After adding #include <dt-bindings/gpio/gpio.h> in the front of DTS file, it is working now.
Thank you.