From d27d1447e49bc6ffa92f787f7bc5c2eea29ba7d2 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.com>
Date: Wed, 30 Sep 2020 12:08:08 +0100
Subject: [PATCH] overlays: Add fsm-demo overlay

fsm-demo demonstrates the usage of the gpio-fsm driver. It is
designed to be used with a set of "traffic light" LEDs on GPIOs
7, 8 and 25.

Signed-off-by: Phil Elwell <phil@raspberrypi.com>
---
 arch/arm/boot/dts/overlays/Makefile           |   1 +
 arch/arm/boot/dts/overlays/README             |   8 ++
 .../boot/dts/overlays/fsm-demo-overlay.dts    | 104 ++++++++++++++++++
 3 files changed, 113 insertions(+)
 create mode 100644 arch/arm/boot/dts/overlays/fsm-demo-overlay.dts

--- a/arch/arm/boot/dts/overlays/Makefile
+++ b/arch/arm/boot/dts/overlays/Makefile
@@ -44,6 +44,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
 	enc28j60-spi2.dtbo \
 	exc3000.dtbo \
 	fe-pi-audio.dtbo \
+	fsm-demo.dtbo \
 	goodix.dtbo \
 	googlevoicehat-soundcard.dtbo \
 	gpio-fan.dtbo \
--- a/arch/arm/boot/dts/overlays/README
+++ b/arch/arm/boot/dts/overlays/README
@@ -767,6 +767,14 @@ Load:   dtoverlay=fe-pi-audio
 Params: <None>
 
 
+Name:   fsm-demo
+Info:   A demonstration of the gpio-fsm driver. The GPIOs are chosen to work
+        nicely with a "traffic-light" display of red, amber and green LEDs on
+        GPIOs 7, 8 and 25 respectively.
+Load:   dtoverlay=fsm-demo,<param>=<val>
+Params: fsm_debug               Enable debug logging (default off)
+
+
 Name:   goodix
 Info:   Enables I2C connected Goodix gt9271 multiple touch controller using
         GPIOs 4 and 17 (pins 7 and 11 on GPIO header) for interrupt and reset.
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/fsm-demo-overlay.dts
@@ -0,0 +1,104 @@
+// Demo overlay for the gpio-fsm driver
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/gpio/gpio-fsm.h>
+
+#define BUTTON1 GF_IP(0)
+#define BUTTON2 GF_SW(0)
+#define RED   GF_OP(0) // GPIO7
+#define AMBER GF_OP(1) // GPIO8
+#define GREEN GF_OP(2) // GPIO25
+
+/{
+	compatible = "brcm,bcm2835";
+
+	fragment@0 {
+		target-path = "/";
+		__overlay__ {
+			fsm_demo: fsm-demo {
+				compatible = "rpi,gpio-fsm";
+
+				debug = <0>;
+				gpio-controller;
+				#gpio-cells = <2>;
+				num-soft-gpios = <1>;
+				gpio-line-names = "button2";
+				input-gpios  = <&gpio 6 1>;  // BUTTON1 (active-low)
+				output-gpios = <&gpio 7 0>,  // RED
+					       <&gpio 8 0>,  // AMBER
+					       <&gpio 25 0>; // GREEN
+				shutdown-timeout-ms = <2000>;
+
+				start {
+					start_state;
+					set = <RED 1>, <AMBER 0>, <GREEN 0>;
+					start2 = <GF_DELAY 250>;
+				};
+
+				start2 {
+					set = <RED 0>, <AMBER 1>;
+					go = <GF_DELAY 250>;
+				};
+
+				go {
+					set = <RED 0>, <AMBER 0>, <GREEN 1>;
+					ready_wait = <BUTTON1 0>;
+					shutdown1 = <GF_SHUTDOWN 0>;
+				};
+
+				ready_wait {
+					// Clear the soft GPIO
+					set = <BUTTON2 0>;
+					ready = <GF_DELAY 1000>;
+					shutdown1 = <GF_SHUTDOWN 0>;
+				};
+
+				ready {
+					stopping = <BUTTON1 1>, <BUTTON2 1>;
+					shutdown1 = <GF_SHUTDOWN 0>;
+				};
+
+				stopping {
+					set = <GREEN 0>, <AMBER 1>;
+					stopped = <GF_DELAY 1000>;
+				};
+
+				stopped {
+					set = <AMBER 0>, <RED 1>;
+					get_set = <GF_DELAY 3000>;
+					shutdown1 = <GF_SHUTDOWN 0>;
+				};
+
+				get_set {
+					set = <AMBER 1>;
+					go = <GF_DELAY 1000>;
+				};
+
+				shutdown1 {
+					set = <RED 0>, <AMBER 0>, <GREEN 1>;
+					shutdown2 = <GF_SHUTDOWN 250>;
+				};
+
+				shutdown2 {
+					set = <AMBER 1>, <GREEN 0>;
+					shutdown3 = <GF_SHUTDOWN 250>;
+				};
+
+				shutdown3 {
+					set = <RED 1>, <AMBER 0>;
+					shutdown4 = <GF_SHUTDOWN 250>;
+				};
+
+				shutdown4 {
+					shutdown_state;
+					set = <RED 0>;
+				};
+			};
+	       };
+        };
+
+	__overrides__ {
+		fsm_debug = <&fsm_demo>,"debug:0";
+	};
+};