feature: modify i2s interface/implementation to better match specific…

…ation

Signed-off-by: deadprogram <[email protected]>

src/examples/i2s/i2s.go

@@ -13,11 +13,11 @@ func main() {
 		Stereo:      true,
 	})
 
-	data := make([]uint32, 64)
+	data := make([]uint16, 64)
 
 	for {
 		// get the next group of samples
-		machine.I2S0.Read(data)
+		machine.I2S0.ReadMono(data)
 
 		println("data", data[0], data[1], data[2], data[4], "...")
 	}

src/machine/board_arduino_mkr1000.go

@@ -74,8 +74,9 @@ const (
 // I2S pins
 const (
 	I2S_SCK_PIN Pin = PA10
-	I2S_SD_PIN  Pin = PA07
-	I2S_WS_PIN      = NoPin // TODO: figure out what this is on Arduino Nano 33.
+	I2S_SDO_PIN Pin = PA07
+	I2S_SDI_PIN     = NoPin
+	I2S_WS_PIN      = NoPin // TODO: figure out what this is on Arduino MKR1000
 )
 
 // USB CDC identifiers

src/machine/board_arduino_mkrwifi1010.go

@@ -74,7 +74,8 @@ const (
 // I2S pins
 const (
 	I2S_SCK_PIN Pin = PA10
-	I2S_SD_PIN  Pin = PA07
+	I2S_SDO_PIN Pin = PA07
+	I2S_SDI_PIN     = NoPin
 	I2S_WS_PIN      = NoPin // TODO: figure out what this is on Arduino MKR WiFi 1010.
 )
 

src/machine/board_arduino_nano33.go

@@ -118,7 +118,8 @@ const (
 // I2S pins
 const (
 	I2S_SCK_PIN Pin = PA10
-	I2S_SD_PIN  Pin = PA08
+	I2S_SDO_PIN Pin = PA08
+	I2S_SDI_PIN     = NoPin
 	I2S_WS_PIN      = NoPin // TODO: figure out what this is on Arduino Nano 33.
 )
 

src/machine/board_arduino_zero.go

@@ -69,7 +69,8 @@ const (
 // I2S pins - might not be exposed
 const (
 	I2S_SCK_PIN Pin = PA10
-	I2S_SD_PIN  Pin = PA07
+	I2S_SDO_PIN Pin = PA07
+	I2S_SDI_PIN     = NoPin
 	I2S_WS_PIN  Pin = PA11
 )
 

src/machine/board_circuitplay_express.go

@@ -102,7 +102,8 @@ var SPI0 = sercomSPIM3
 // I2S pins
 const (
 	I2S_SCK_PIN = PA10
-	I2S_SD_PIN  = PA08
+	I2S_SDO_PIN = PA08
+	I2S_SDI_PIN = NoPin
 	I2S_WS_PIN  = NoPin // no WS, instead uses SCK to sync
 )
 

src/machine/board_feather-m0-express.go

@@ -81,7 +81,8 @@ var SPI0 = sercomSPIM4
 // I2S pins
 const (
 	I2S_SCK_PIN = PA10
-	I2S_SD_PIN  = PA07
+	I2S_SDO_PIN = PA07
+	I2S_SDI_PIN = NoPin
 	I2S_WS_PIN  = NoPin // TODO: figure out what this is on Feather M0 Express.
 )
 

src/machine/board_feather-m0.go

@@ -76,7 +76,8 @@ var SPI0 = sercomSPIM4
 // I2S pins
 const (
 	I2S_SCK_PIN = PA10
-	I2S_SD_PIN  = PA08
+	I2S_SDO_PIN = PA08
+	I2S_SDI_PIN = NoPin
 	I2S_WS_PIN  = NoPin // TODO: figure out what this is on Feather M0.
 )
 

src/machine/board_gemma-m0.go

@@ -76,7 +76,8 @@ var (
 // I2S (not connected, needed for atsamd21).
 const (
 	I2S_SCK_PIN = NoPin
-	I2S_SD_PIN  = NoPin
+	I2S_SDO_PIN = NoPin
+	I2S_SDI_PIN = NoPin
 	I2S_WS_PIN  = NoPin
 )
 

src/machine/board_grandcentral-m4.go

@@ -224,7 +224,8 @@ const (
 
 	I2S_SCK_PIN = I2S0_SCK_PIN // default pins
 	I2S_WS_PIN  = I2S0_FS_PIN  //
-	I2S_SD_PIN  = I2S0_SDO_PIN //
+	I2S_SDO_PIN = I2S0_SDO_PIN
+	I2S_SDI_PIN = NoPin
 )
 
 // SD card pins

src/machine/board_itsybitsy-m0.go

@@ -89,7 +89,8 @@ var SPI1 = sercomSPIM5
 // I2S pins
 const (
 	I2S_SCK_PIN = PA10
-	I2S_SD_PIN  = PA08
+	I2S_SDO_PIN = PA08
+	I2S_SDI_PIN = NoPin
 	I2S_WS_PIN  = NoPin // TODO: figure out what this is on ItsyBitsy M0.
 )
 

src/machine/board_p1am-100.go

@@ -123,7 +123,8 @@ var (
 // I2S pins
 const (
 	I2S_SCK_PIN Pin = D2
-	I2S_SD_PIN  Pin = A6
+	I2S_SDO_PIN Pin = A6
+	I2S_SDI_PIN     = NoPin
 	I2S_WS_PIN      = D3
 )
 

src/machine/board_qtpy.go

@@ -81,7 +81,8 @@ var (
 // I2S pins
 const (
 	I2S_SCK_PIN = PA10
-	I2S_SD_PIN  = PA08
+	I2S_SDO_PIN = PA08
+	I2S_SDI_PIN = NoPin // TODO: figure out what this is on QT Py M0.
 	I2S_WS_PIN  = NoPin // TODO: figure out what this is on QT Py M0.
 )
 

src/machine/board_trinket.go

@@ -67,7 +67,8 @@ var (
 // I2S pins
 const (
 	I2S_SCK_PIN = PA10
-	I2S_SD_PIN  = PA08
+	I2S_SDO_PIN = PA08
+	I2S_SDI_PIN = NoPin // TODO: figure out what this is on Trinket M0.
 	I2S_WS_PIN  = NoPin // TODO: figure out what this is on Trinket M0.
 )
 

src/machine/board_wioterminal.go

@@ -376,6 +376,14 @@ var (
 	I2C1 = sercomI2CM3
 )
 
+// I2S pins
+const (
+	I2S_SCK_PIN = BCM18
+	I2S_SDO_PIN = BCM21
+	I2S_SDI_PIN = BCM20
+	I2S_WS_PIN  = BCM19
+)
+
 // SPI pins
 const (
 	SPI0_SCK_PIN = SCK // SCK:  SERCOM5/PAD[1]

src/machine/board_xiao.go

@@ -82,7 +82,8 @@ var SPI0 = sercomSPIM0
 // I2S pins
 const (
 	I2S_SCK_PIN = PA10
-	I2S_SD_PIN  = PA08
+	I2S_SDO_PIN = PA08
+	I2S_SDI_PIN = NoPin // TODO: figure out what this is on Xiao
 	I2S_WS_PIN  = NoPin // TODO: figure out what this is on Xiao
 )
 

src/machine/i2s.go

@@ -1,4 +1,4 @@
-//go:build sam
+//go:build sam && atsamd21
 
 // This is the definition for I2S bus functions.
 // Actual implementations if available for any given hardware
@@ -9,6 +9,22 @@
 
 package machine
 
+import "errors"
+
+// If you are getting a compile error on this line please check to see you've
+// correctly implemented the methods on the I2S type. They must match
+// the interface method signatures type to type perfectly.
+// If not implementing the I2S type please remove your target from the build tags
+// at the top of this file.
+var _ interface {
+	SetSampleFrequency(freq uint32) error
+	ReadMono(b []uint16) (int, error)
+	ReadStereo(b []uint32) (int, error)
+	WriteMono(b []uint16) (int, error)
+	WriteStereo(b []uint32) (int, error)
+	Enable(enabled bool)
+} = (*I2S)(nil)
+
 type I2SMode uint8
 type I2SStandard uint8
 type I2SClockSource uint8
@@ -18,6 +34,7 @@ const (
 	I2SModeSource I2SMode = iota
 	I2SModeReceiver
 	I2SModePDM
+	I2SModeSourceReceiver
 )
 
 const (
@@ -39,11 +56,20 @@ const (
 	I2SDataFormat32bit                 = 32
 )
 
+var (
+	ErrInvalidSampleFrequency = errors.New("i2s: invalid sample frequency")
+)
+
 // All fields are optional and may not be required or used on a particular platform.
 type I2SConfig struct {
-	SCK             Pin
-	WS              Pin
-	SD              Pin
+	// clock
+	SCK Pin
+	// word select
+	WS Pin
+	// data out
+	SDO Pin
+	// data in
+	SDI             Pin
 	Mode            I2SMode
 	Standard        I2SStandard
 	ClockSource     I2SClockSource