stepper-pinmux.dtsi

#include "bone/black.h"

// note: P9.41 and P9.42 both connect to two processor pins each, which
// cape-universal calls P9_41/42 and P9_91/92 respectively.
USES_PIN(P9_41);
USES_PIN(P9_91);
USES_PIN(P9_42);
USES_PIN(P9_92);

// create pinmux helper to switch between disabled and active states for
// pruout pins, to allow userspace to initialize R30 before changing the pinmux
/ {
    stepper-pinmux {
        compatible = "bone-pinmux-helper";
        pinctrl-names = "default", "active";
        pinctrl-0 = <&stepper_unused_pins>, <&stepper_disabled_pins>;
        pinctrl-1 = <&stepper_unused_pins>, <&stepper_active_pins>;
    };
};

&am33xx_pinmux {
    stepper_unused_pins: stepper-unused {
        pinctrl-single,pins = <
            PIN_NOPULL( P9_41a, 7 )
            PIN_NOPULL( P9_42a, 7 )
        >;
    };
    stepper_disabled_pins: stepper-disabled {
        pinctrl-single,pins = <
            PIN_PULLDN( P9_41b, 7 )
            PIN_PULLDN( P9_42b, 7 )
        >;
    };
    stepper_active_pins: stepper-active {
        pinctrl-single,pins = <
            PIN_PULLDN( P9_41b, 5 )  // pru 0 out 6
            PIN_PULLDN( P9_42b, 5 )  // pru 0 out 4
        >;
    };
};