Move the setting of alternate functions for PWM pins to the PWM code …

…where it belongs, rather than GPIO code.
Jon-Bright · Feb 21, 2021 · 3e49afc · 3e49afc
1 parent a3350ab
commit 3e49afc
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Showing 3 changed files with 12 additions and 12 deletions.
diff --git a/pixarray/ws281x.go b/pixarray/ws281x.go
@@ -49,12 +49,12 @@ func NewWS281x(numPixels int, numColors int, order int, freq uint, dma int, pins
  rp.FreeDMABuf(wa.pixDMA) // Ignore error
  return nil, fmt.Errorf("couldn't init registers: %v", err)
  }
- err = rp.InitGPIO(pins)
+ err = rp.InitGPIO()
  if err != nil {
  rp.FreeDMABuf(wa.pixDMA) // Ignore error
  return nil, fmt.Errorf("couldn't init GPIO: %v", err)
  }
- err = rp.InitPWM(freq, wa.pixDMA, bytes)
+ err = rp.InitPWM(freq, wa.pixDMA, bytes, pins)
  if err != nil {
  rp.FreeDMABuf(wa.pixDMA) // Ignore error
  return nil, fmt.Errorf("couldn't init PWM: %v", err)

diff --git a/rpi/gpio.go b/rpi/gpio.go
@@ -48,7 +48,7 @@ func (rp *RPi) gpioFunctionSet(pin int, alt int) error {
  return nil
 }
 
-func (rp *RPi) InitGPIO(pins []int) error {
+func (rp *RPi) InitGPIO() error {
  var (
  bufOffs uintptr
  err error
@@ -59,13 +59,5 @@ func (rp *RPi) InitGPIO(pins []int) error {
  }
  log.Printf("Got gpioBuf[%d], offset %d\n", len(rp.gpioBuf), bufOffs)
  rp.gpio = (*gpioT)(unsafe.Pointer(&rp.gpioBuf[bufOffs]))
-
- for channel, pin := range pins {
- alt, ok := pwmPinToAlt[pwmPin{channel, pin}]
- if !ok {
- return fmt.Errorf("invalid pin %d for PWM channel %d", pin, channel)
- }
- rp.gpioFunctionSet(pin, alt)
- }
  return nil
 }
diff --git a/rpi/pwm.go b/rpi/pwm.go
@@ -62,12 +62,20 @@ func rpiDmaTiPerMap(val uint32) uint32 {
  return (val & 0x1f) << 16
 }
 
-func (rp *RPi) InitPWM(freq uint, buf *DMABuf, bytes uint) error {
+func (rp *RPi) InitPWM(freq uint, buf *DMABuf, bytes uint, pins []int) error {
  oscFreq := uint32(OSC_FREQ)
  if rp.hw.hwType == RPI_HWVER_TYPE_PI4 {
  oscFreq = OSC_FREQ_PI4
  }
 
+ for channel, pin := range pins {
+ alt, ok := pwmPinToAlt[pwmPin{channel, pin}]
+ if !ok {
+ return fmt.Errorf("invalid pin %d for PWM channel %d", pin, channel)
+ }
+ rp.gpioFunctionSet(pin, alt)
+ }
+
  if rp.pwmBuf == nil {
  var (
  bufOffs uintptr