simplify package structure

gpio.go

@@ -0,0 +1,89 @@
+package embd
+
+type Direction int
+
+const (
+	In Direction = iota
+	Out
+)
+
+const (
+	Low int = iota
+	High
+)
+
+type DigitalPin interface {
+	Write(val int) error
+	Read() (int, error)
+
+	SetDirection(dir Direction) error
+	ActiveLow(b bool) error
+
+	PullUp() error
+	PullDown() error
+
+	Close() error
+}
+
+type GPIO interface {
+	DigitalPin(key interface{}) (DigitalPin, error)
+
+	Close() error
+}
+
+var gpioInstance GPIO
+
+func InitGPIO() error {
+	desc, err := DescribeHost()
+	if err != nil {
+		return err
+	}
+
+	gpioInstance = desc.GPIO()
+
+	return nil
+}
+
+func CloseGPIO() error {
+	return gpioInstance.Close()
+}
+
+func NewDigitalPin(key interface{}) (DigitalPin, error) {
+	return gpioInstance.DigitalPin(key)
+}
+
+func DigitalWrite(key interface{}, val int) error {
+	pin, err := NewDigitalPin(key)
+	if err != nil {
+		return err
+	}
+
+	return pin.Write(val)
+}
+
+func DigitalRead(key interface{}) (int, error) {
+	pin, err := NewDigitalPin(key)
+	if err != nil {
+		return 0, err
+	}
+
+	return pin.Read()
+}
+
+func SetDirection(key interface{}, dir Direction) error {
+	pin, err := NewDigitalPin(key)
+	if err != nil {
+		return err
+	}
+
+	return pin.SetDirection(dir)
+}
+
+func ActiveLow(key interface{}, b bool) error {
+	pin, err := NewDigitalPin(key)
+	if err != nil {
+		return err
+	}
+
+	return pin.ActiveLow(b)
+}