refactor(cdc): integrate cdc package with usb.Controller

Author: mikesmitty

src/machine/machine_atsamd21_usb.go

@@ -378,7 +378,7 @@ func sendUSBPacket(ep uint32, data []byte, maxsize uint16) {
 	usbEndpointDescriptors[ep].DeviceDescBank[1].PCKSIZE.SetBits((uint32(l) & usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask) << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
 }
 
-func ReceiveUSBControlPacket() ([cdcLineInfoSize]byte, error) {
+func (dev *USBDevice) ReceiveUSBControlPacket() ([cdcLineInfoSize]byte, error) {
 	var b [cdcLineInfoSize]byte
 
 	// Wait until OUT transfer is ready.

src/machine/machine_atsamd51_usb.go

@@ -381,7 +381,7 @@ func sendUSBPacket(ep uint32, data []byte, maxsize uint16) {
 	usbEndpointDescriptors[ep].DeviceDescBank[1].PCKSIZE.SetBits((uint32(l) & usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask) << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
 }
 
-func ReceiveUSBControlPacket() ([cdcLineInfoSize]byte, error) {
+func (dev *USBDevice) ReceiveUSBControlPacket() ([cdcLineInfoSize]byte, error) {
 	var b [cdcLineInfoSize]byte
 
 	// Wait until OUT transfer is ready.

src/machine/machine_nrf52840_usb.go

@@ -372,7 +372,7 @@ func handleUSBSetAddress(setup usb.Setup) bool {
 	return true
 }
 
-func ReceiveUSBControlPacket() ([cdcLineInfoSize]byte, error) {
+func (dev *USBDevice) ReceiveUSBControlPacket() ([cdcLineInfoSize]byte, error) {
 	var b [cdcLineInfoSize]byte
 
 	nrf.USBD.TASKS_EP0RCVOUT.Set(1)

src/machine/machine_rp2_usb.go

@@ -104,7 +104,7 @@ func sendUSBPacket(ep uint32, data []byte, maxsize uint16) {
 	sendViaEPIn(ep, data, count)
 }
 
-func ReceiveUSBControlPacket() ([cdcLineInfoSize]byte, error) {
+func (dev *USBDevice) ReceiveUSBControlPacket() ([cdcLineInfoSize]byte, error) {
 	var b [cdcLineInfoSize]byte
 	ep := 0
 

src/machine/usb.go

@@ -19,19 +19,24 @@ var (
 	USBCDC Serialer
 )
 
-func initUSB() {
-	enableUSBCDC()
-	USBDev.Configure(UARTConfig{})
-
+func init() {
 	usb.DefaultController = USBDev
 }
 
+func initUSB() {
+	USBDev.Enable()
+}
+
 // Using go:linkname here because there's a circular dependency between the
 // machine package and the machine/usb/cdc package.
 //
 //go:linkname enableUSBCDC machine/usb/cdc.EnableUSBCDC
 func enableUSBCDC()
 
+func ReceiveUSBControlPacket() ([7]byte, error) {
+	return USBDev.ReceiveUSBControlPacket()
+}
+
 type Serialer interface {
 	WriteByte(c byte) error
 	Write(data []byte) (n int, err error)
@@ -287,6 +292,15 @@ func handleStandardSetup(setup usb.Setup) bool {
 	}
 }
 
+func (d *USBDevice) Enable() {
+	if d.initcomplete {
+		return
+	}
+	enableUSBCDC()
+	d.Configure(UARTConfig{})
+	d.initcomplete = true
+}
+
 func (d *USBDevice) IsInitEndpointComplete() bool {
 	return d.InitEndpointComplete
 }

src/machine/usb/cdc/cdc.go

@@ -1,5 +1,7 @@
 package cdc
 
+import "machine/usb"
+
 const (
 	cdcEndpointACM = 1
 	cdcEndpointOut = 2
@@ -12,6 +14,7 @@ func New() *USBCDC {
 		USB = &USBCDC{
 			rxBuffer: NewRxRingBuffer(),
 			txBuffer: NewTxRingBuffer(),
+			dev:      usb.DefaultController,
 		}
 	}
 	return USB

src/machine/usb/cdc/usbcdc.go

@@ -70,6 +70,7 @@ type USBCDC struct {
 	rxBuffer *rxRingBuffer
 	txBuffer *txRingBuffer
 	waitTxc  bool
+	dev      usb.Controller
 }
 
 var (
@@ -88,7 +89,7 @@ func (usbcdc *USBCDC) Configure(config machine.UARTConfig) error {
 func (usbcdc *USBCDC) Flush() {
 	mask := interrupt.Disable()
 	if b, ok := usbcdc.txBuffer.Get(); ok {
-		machine.SendUSBInPacket(cdcEndpointIn, b)
+		usbcdc.dev.SendUSBInPacket(cdcEndpointIn, b)
 	} else {
 		usbcdc.waitTxc = false
 	}
@@ -123,15 +124,15 @@ func (usbcdc *USBCDC) RTS() bool {
 	return (usbLineInfo.lineState & usb_CDC_LINESTATE_RTS) > 0
 }
 
-func cdcCallbackRx(b []byte) {
+func (usbcdc *USBCDC) Rx(b []byte) {
 	for i := range b {
-		USB.Receive(b[i])
+		usbcdc.Receive(b[i])
 	}
 }
 
 var cdcSetupBuff [cdcLineInfoSize]byte
 
-func cdcSetup(setup usb.Setup) bool {
+func (usbcdc *USBCDC) Setup(setup usb.Setup) bool {
 	if setup.BmRequestType == usb_REQUEST_DEVICETOHOST_CLASS_INTERFACE {
 		if setup.BRequest == usb_CDC_GET_LINE_CODING {
 			cdcSetupBuff[0] = byte(usbLineInfo.dwDTERate)
@@ -142,14 +143,14 @@ func cdcSetup(setup usb.Setup) bool {
 			cdcSetupBuff[5] = byte(usbLineInfo.bParityType)
 			cdcSetupBuff[6] = byte(usbLineInfo.bDataBits)
 
-			machine.SendUSBInPacket(0, cdcSetupBuff[:])
+			usbcdc.dev.SendUSBInPacket(0, cdcSetupBuff[:])
 			return true
 		}
 	}
 
 	if setup.BmRequestType == usb_REQUEST_HOSTTODEVICE_CLASS_INTERFACE {
 		if setup.BRequest == usb_CDC_SET_LINE_CODING {
-			b, err := machine.ReceiveUSBControlPacket()
+			b, err := usbcdc.dev.ReceiveUSBControlPacket()
 			if err != nil {
 				return false
 			}
@@ -171,21 +172,22 @@ func cdcSetup(setup usb.Setup) bool {
 			} else {
 				// TODO: cancel any reset
 			}
-			machine.SendZlp()
+			usbcdc.dev.SendZlp()
 		}
 
 		if setup.BRequest == usb_CDC_SEND_BREAK {
 			// TODO: something with this value?
 			// breakValue = ((uint16_t)setup.wValueH << 8) | setup.wValueL;
 			// return false;
-			machine.SendZlp()
+			usbcdc.dev.SendZlp()
 		}
 		return true
 	}
 	return false
 }
 
 func EnableUSBCDC() {
-	machine.USBCDC = New()
-	machine.EnableCDC(USB.Flush, cdcCallbackRx, cdcSetup)
+	c := New()
+	machine.USBCDC = c
+	machine.EnableCDC(c.Flush, c.Rx, c.Setup)
 }

src/machine/usb/device.go

@@ -6,6 +6,7 @@ import (
 
 // Controller abstracts the USB interactions to allow for testing without hardware.
 type Controller interface {
+	Enable()
 	ConfigureUSBEndpoint(desc descriptor.Descriptor, epSettings []EndpointConfig, setup []SetupConfig)
 	SendUSBInPacket(ep uint32, data []byte) bool
 	AckUsbOutTransfer(ep uint32)
@@ -15,6 +16,7 @@ type Controller interface {
 	SetStallEPOut(ep uint32)
 	ClearStallEPIn(ep uint32)
 	ClearStallEPOut(ep uint32)
+	ReceiveUSBControlPacket() ([7]byte, error)
 }
 
 var DefaultController Controller

src/machine/usb/msc/mock_usb_device.go

@@ -54,3 +54,10 @@ func (m *MockUSBDevice) ClearStallEPIn(ep uint32) {
 func (m *MockUSBDevice) ClearStallEPOut(ep uint32) {
 	m.StallOut = false
 }
+
+func (m *MockUSBDevice) Enable() {
+}
+
+func (m *MockUSBDevice) ReceiveUSBControlPacket() ([7]byte, error) {
+	return [7]byte{}, nil
+}

src/machine/usb/msc/msc.go

@@ -80,6 +80,7 @@ func newMSC(dev BlockDevice, usbCtrl usb.Controller) *msc {
 		maxPacketSize: uint32(maxPacketSize),
 		usb:           usbCtrl,
 	}
+	m.usb.Enable()
 	m.RegisterBlockDevice(dev)
 
 	// Set default inquiry data fields