issue-17: gpio init functions and more

gpio/gpio.go

@@ -0,0 +1,96 @@
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+)
+
+const (
+	gpioExportFile = "/sys/class/gpio/export"
+
+	gpio27Dir = "/sys/class/gpio/gpio27"
+	gpio22Dir = "/sys/class/gpio/gpio22"
+
+	gpio27DirectionFile = gpio27Dir + "/direction"
+	gpio22DirectionFile = gpio22Dir + "/direction"
+
+	gpio27ValueFile = gpio27Dir + "/value"
+	gpio22ValueFile = gpio22Dir + "/value"
+)
+
+const (
+	// Hot
+	Hot = 22
+	// Cold
+	Cold = 27
+)
+
+// NinetyNineInputRules
+const NinetyNineInputRules = `SUBSYSTEM=="input", GROUP="input", MODE="0660"`
+
+// Toggle
+func Toggle(relay int, onOff string) error {
+	switch onOff {
+	case "0":
+		switch relay {
+		case 22:
+			if err := ioutil.WriteFile(gpio22ValueFile, []byte(onOff), 0644); err != nil {
+				log.Fatalln(err)
+			}
+			fmt.Println("relay off cold")
+		case 27:
+			if err := ioutil.WriteFile(gpio27ValueFile, []byte(onOff), 0644); err != nil {
+				log.Fatalln(err)
+			}
+			fmt.Println("relay off cold")
+		}
+	case "1":
+		switch relay {
+		case 22:
+			if err := ioutil.WriteFile(gpio22ValueFile, []byte(onOff), 0644); err != nil {
+				log.Fatalln(err)
+			}
+			fmt.Println("relay on cold")
+		case 27:
+			if err := ioutil.WriteFile(gpio27ValueFile, []byte(onOff), 0644); err != nil {
+				log.Fatalln(err)
+			}
+			fmt.Println("relay on cold")
+		}
+	}
+
+	return nil
+}
+
+func init() {
+	for _, i := range []string{"22", "27"} {
+		if err := ioutil.WriteFile(gpioExportFile, []byte(i), 0644); err != nil {
+			log.Fatalln(err)
+		}
+	}
+
+	for _, i := range []string{gpio22DirectionFile, gpio27DirectionFile} {
+		if err := ioutil.WriteFile(i, []byte("out"), 0644); err != nil {
+			log.Fatalln(err)
+		}
+	}
+
+	for _, i := range []string{gpio22Dir, gpio27Dir} {
+		if err := chmodr(i, 0777); err != nil {
+			log.Fatalln(err)
+		}
+	}
+}
+
+// chmodr
+func chmodr(path string, perms int) error {
+	return filepath.Walk(path, func(name string, info os.FileInfo, err error) error {
+		if err == nil {
+			err = os.Chmod(name, os.FileMode(perms))
+		}
+		return err
+	})
+}