Device Tree Overlay file for GPS Cape

BBB-WACAN-GPS-00A2.dts

/*
 * Copyright (C) 2016 Shane Short <[email protected]>
 * Hardware design by Brenton Hewitt <[email protected]>
 *
 * Combined GPS (with PPS) and Dallas 1W sensor bus cape.
 */
/dts-v1/;
/plugin/;

#include <dt-bindings/board/am335x-bbw-bbb-base.h>
#include <dt-bindings/gpio/gpio.h>
#include <dt-bindings/pinctrl/am33xx.h>

/ {
  compatible = "ti,beaglebone", "ti,beaglebone-black", "ti,beaglebone-green";

  /* identification */
  part-number = "BBB-WACAN-GPS";
  version = "00A2";

	/* state the resources this cape uses */
	exclusive-use =
		"P8.8",          /* GPS PPS Signal */
		"P9.11",         /* UART4_rxd */
		"P9.13",         /* UART4_txd */
		"P9.22",         /* Dallas 1W Bus

   /* the hardware ip uses */
   "uart4",
   "gpio2_3";

	/*
	 * Helper to show loaded overlays under: /proc/device-tree/chosen/overlays/
	 */
	fragment@0 {
		target-path="/";
		__overlay__ {

			chosen {
				overlays {
					BBB-WACAN-GPS-00A2 = __TIMESTAMP__;
				};
			};
		};
	};

	/*
	 * Free up the pins used by the cape from the pinmux helpers.
	 */
	fragment@1 {
		target = <&ocp>;
		__overlay__ {
			P9_12_pinmux { status = "disabled"; };
		};
	};

	fragment@2 {
		target = <&am33xx_pinmux>;
		__overlay__ {

			dallas_w1_pins: pinmux_dallas_w1_pins {
				pinctrl-single,pins = < 
					BONE_P9_22 (INPUT_EN | PULL_UP | MUX_MODE7)
				>;
			};

      bb_uart4_pins: pinmux_bb_uart4_pins {
        pinctrl-single,pins = <
          BONE_P9_13 (PIN_OUTPUT | MUX_MODE6)
          BONE_P9_11 (PIN_INPUT  | MUX_MODE6)
        >;
      };

      /* GPS 1 PPS Input */
      gps_pps_pins: pinmux_gps_pps_pins {
        pinctrl-single,pins = < BONE_P8_08 (PIN_INPUT | MUX_MODE7) >;
      };

		};
	};

  fragment@3 {
    target-path="/";
    __overlay__ {

      onewire {
        status = "okay";
        pinctrl-names = "default";
        pinctrl-0 = <&dallas_w1_pins>;

        compatible = "w1-gpio";
        gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>;
      };
    };
  };
  

  fragment@4 {
    target = <&uart4>;
    __overlay__ {
       status = "okay";
       pinctrl-names = "default";
       pinctrl-0 = <&bb_uart4_pins>;
    };
  };

  fragment@5 {
    target = <&ocp>;
     __overlay__ {
      pps {
        compatible = "pps-gpio";
        status = "okay";
        pinctrl-names = "default";
        pinctrl-0 = <&gps_pps_pins>;
        gpios = <&gpio2 3 0 >;
        assert-rising-edge;
      };
    };
  };
};