Hi All, I am playing around with the capabilities of the camkes-arm-vm project pn the Tegra TK1 and and wondering if someone else has come across this issue. It looks like GPIO functionality is not available in the buildroot. I can confirm the GPIO source is present and is being built: camkes-arm-vm/libs/libplatsupport/rc/plat/tk1/gpio.c camkes-arm-vm/libs/libplatsupport/plat_include/tk1/platsupport/plat/gpio.h [CC] src/plat/tk1/gpio.o The expected sysfs support is not present and looking and the relevant dmesg: # dmesg | grep gpio [ 0.057543] gpiochip_add: GPIOs 0..255 (tegra-gpio) failed to register [ 1.485061] input: gpio-keys as /devices/soc0/gpio-keys/input/input0 Any thoughts on what could be causing GPIO to the failing to register? Steven