matrix4x3: client should ensure rpio is initialised before using

interface/keypad/matrix4x3/matrix4x3.go

@@ -78,7 +78,7 @@ type Matrix4x3 interface {
 	PressedKey() (Key, error)
 
 	// Close.
-	Close() error
+	Close()
 }
 
 type matrix4x3 struct {
@@ -127,10 +127,6 @@ func (d *matrix4x3) setup() (err error) {
 	d.mu.Lock()
 	defer d.mu.Unlock()
 
-	if err = rpio.Open(); err != nil {
-		return
-	}
-
 	for i := 0; i < rows; i++ {
 		d.rpioRowPins[i].Input()
 		d.rpioRowPins[i].PullUp()
@@ -210,12 +206,8 @@ func (d *matrix4x3) Run() {
 }
 
 // Close.
-func (d *matrix4x3) Close() (err error) {
+func (d *matrix4x3) Close() {
 	if d.quit != nil {
 		d.quit <- true
 	}
-
-	rpio.Close()
-
-	return
 }

samples/keypad/matrix4x3.go

@@ -5,12 +5,16 @@ import (
 	"time"
 
 	"github.com/kid0m4n/go-rpi/interface/keypad/matrix4x3"
+	"github.com/stianeikeland/go-rpio"
 )
 
 func main() {
 	rowPins := []int{4, 17, 27, 22}
 	colPins := []int{23, 24, 25}
 
+	rpio.Open()
+	defer rpio.Close()
+
 	keypad := matrix4x3.New(rowPins, colPins)
 
 	for {