piglow: various readability improvements

goiot · Jun 24, 2016 · aa02a85 · aa02a85
1 parent d12108a
commit aa02a85
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Showing 4 changed files with 74 additions and 185 deletions.
diff --git a/piglow/examples_test.go → piglow/example_test.go b/piglow/examples_test.go → piglow/example_test.go
@@ -8,9 +8,14 @@ import (
 )
 
 func Example() {
-	p, _ := piglow.Open(&i2c.Devfs{Dev: "/dev/i2c-1", Addr: piglow.Address})
+	p, err := piglow.Open(&i2c.Devfs{Dev: "/dev/i2c-1", Addr: piglow.Address})
+	if err != nil {
+		panic(err)
+	}
 
-	p.Setup()
+	if err := p.Setup(); err != nil {
+		panic(err)
+	}
 
 	brightness := 0
 	for i := 0; i < 10; i++ {

diff --git a/piglow/examples/strobe.go b/piglow/examples/strobe.go
@@ -1,9 +1,6 @@
 package main
 
 import (
-	"os"
-	"os/signal"
-	"syscall"
 	"time"
 
 	"github.com/goiot/devices/piglow"
@@ -16,42 +13,24 @@ func main() {
 		panic(err)
 	}
 
-	// catch signals and terminate the app
-	sigc := make(chan os.Signal, 1)
-	signal.Notify(sigc,
-		syscall.SIGHUP,
-		syscall.SIGINT,
-		syscall.SIGTERM,
-		syscall.SIGQUIT)
+	defer func() {
+		p.Shutdown()
+		p.Close()
+	}()
 
-	if err := p.Setup(); err != nil {
-		panic(err)
+	time.Sleep(50 * time.Millisecond)
+	for i := 1; i <= 18; i++ {
+		if err := p.SetLEDBrightness(i, 1); err != nil {
+			panic(err)
+		}
+		time.Sleep(10 * time.Millisecond)
 	}
 
-	for {
-		select {
-		case <-sigc:
-			p.Shutdown()
-			p.Close()
-			return
-		default:
-			time.Sleep(50 * time.Millisecond)
-
-			for i := 1; i <= 18; i++ {
-				if err := p.SetLEDBrightness(i, 1); err != nil {
-					panic(err)
-				}
-				time.Sleep(10 * time.Millisecond)
-			}
-
-			time.Sleep(50 * time.Millisecond)
-
-			for i := 18; i > 0; i-- {
-				if err := p.SetLEDBrightness(i, 0); err != nil {
-					panic(err)
-				}
-				time.Sleep(10 * time.Millisecond)
-			}
+	time.Sleep(50 * time.Millisecond)
+	for i := 18; i > 0; i-- {
+		if err := p.SetLEDBrightness(i, 0); err != nil {
+			panic(err)
 		}
+		time.Sleep(10 * time.Millisecond)
 	}
 }
diff --git a/piglow/piglow.go b/piglow/piglow.go
@@ -17,11 +17,7 @@ type PiGlow struct {
 
 // Reset resets the internal registers
 func (p *PiGlow) Reset() error {
-	if err := p.conn.Write([]byte{0x17, 0xFF}); err != nil {
-		return err
-	}
-
-	return nil
+	return p.conn.Write([]byte{0x17, 0xFF})
 }
 
 // Shutdown sets the software shutdown mode of the PiGlow
@@ -40,23 +36,18 @@ func (p *PiGlow) Setup() error {
 	if err := p.Reset(); err != nil {
 		return err
 	}
-
 	if err := p.Enable(); err != nil {
 		return err
 	}
-
 	if err := p.SetLEDControlRegister(1, 0xFF); err != nil {
 		return err
 	}
-
 	if err := p.SetLEDControlRegister(2, 0xFF); err != nil {
 		return err
 	}
-
 	if err := p.SetLEDControlRegister(3, 0xFF); err != nil {
 		return err
 	}
-
 	return nil
 }
 
@@ -68,8 +59,8 @@ func Open(o driver.Opener) (*PiGlow, error) {
 	if err != nil {
 		return nil, err
 	}
-
-	return &PiGlow{conn: conn}, nil
+	g := &PiGlow{conn: conn}
+	return g, nil
 }
 
 // Close frees the underlying resources. It must be called once
@@ -83,19 +74,15 @@ func (p *PiGlow) Green(level int) error {
 	if err := p.conn.Write([]byte{0x04, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x06, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x0E, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x16, 0xFF}); err != nil {
 		return err
 	}
-
 	return nil
 }
 
@@ -104,19 +91,15 @@ func (p *PiGlow) Blue(level int) error {
 	if err := p.conn.Write([]byte{0x05, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x0C, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x0F, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x16, 0xFF}); err != nil {
 		return err
 	}
-
 	return nil
 }
 
@@ -125,19 +108,15 @@ func (p *PiGlow) Yellow(level int) error {
 	if err := p.conn.Write([]byte{0x03, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x09, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x10, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x16, 0xFF}); err != nil {
 		return err
 	}
-
 	return nil
 }
 
@@ -146,19 +125,15 @@ func (p *PiGlow) Orange(level int) error {
 	if err := p.conn.Write([]byte{0x02, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x08, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x11, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x16, 0xFF}); err != nil {
 		return err
 	}
-
 	return nil
 }
 
@@ -167,19 +142,15 @@ func (p *PiGlow) White(level int) error {
 	if err := p.conn.Write([]byte{0x0A, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x0B, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x0D, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x16, 0xFF}); err != nil {
 		return err
 	}
-
 	return nil
 }
 
@@ -188,20 +159,13 @@ func (p *PiGlow) Red(level int) error {
 	if err := p.conn.Write([]byte{0x01, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x07, byte(level)}); err != nil {
 		return err
 	}
-
 	if err := p.conn.Write([]byte{0x12, byte(level)}); err != nil {
 		return err
 	}
-
-	if err := p.conn.Write([]byte{0x16, 0xFF}); err != nil {
-		return err
-	}
-
-	return nil
+	return p.conn.Write([]byte{0x16, 0xFF})
 }
 
 // SetLEDControlRegister sets the control register 1-3 to the bitmask enables.
@@ -228,25 +192,15 @@ func (p *PiGlow) SetLEDControlRegister(register, enables int) error {
 	if err := p.conn.Write([]byte{address, byte(enables)}); err != nil {
 		return err
 	}
-
-	if err := p.conn.Write([]byte{0x16, 0xFF}); err != nil {
-		return err
-	}
-
-	return nil
+	return p.conn.Write([]byte{0x16, 0xFF})
 }
 
 // SetLEDBrightness sets the led 1-18 to the level 0-255.
 func (p *PiGlow) SetLEDBrightness(led, level int) error {
 	if err := p.conn.Write([]byte{byte(led), byte(level)}); err != nil {
 		return err
 	}
-
-	if err := p.conn.Write([]byte{0x16, 0xFF}); err != nil {
-		return err
-	}
-
-	return nil
+	return p.conn.Write([]byte{0x16, 0xFF})
 }
 
 // SetBrightness sets all the LEDs to the level 0-255.
@@ -256,10 +210,5 @@ func (p *PiGlow) SetBrightness(level int) error {
 			return err
 		}
 	}
-
-	if err := p.conn.Write([]byte{0x16, 0xFF}); err != nil {
-		return err
-	}
-
-	return nil
+	return p.conn.Write([]byte{0x16, 0xFF})
 }