tinygo/src/machine/usb.go
deadprogram b661882391 machine/usbcdc: remove remaining heap allocations for USB CDC implementations
Signed-off-by: deadprogram <ron@hybridgroup.com>
2021-04-23 23:37:24 +02:00

754 строки
22 КиБ
Go

// +build sam nrf52840
package machine
import (
"errors"
"runtime/volatile"
)
const deviceDescriptorSize = 18
var (
errUSBCDCBufferEmpty = errors.New("USB-CDC buffer empty")
errUSBCDCWriteByteTimeout = errors.New("USB-CDC write byte timeout")
errUSBCDCReadTimeout = errors.New("USB-CDC read timeout")
errUSBCDCBytesRead = errors.New("USB-CDC invalid number of bytes read")
)
// DeviceDescriptor implements the USB standard device descriptor.
//
// Table 9-8. Standard Device Descriptor
// bLength, bDescriptorType, bcdUSB, bDeviceClass, bDeviceSubClass, bDeviceProtocol, bMaxPacketSize0,
// idVendor, idProduct, bcdDevice, iManufacturer, iProduct, iSerialNumber, bNumConfigurations */
//
type DeviceDescriptor struct {
bLength uint8 // 18
bDescriptorType uint8 // 1 USB_DEVICE_DESCRIPTOR_TYPE
bcdUSB uint16 // 0x200
bDeviceClass uint8
bDeviceSubClass uint8
bDeviceProtocol uint8
bMaxPacketSize0 uint8 // Packet 0
idVendor uint16
idProduct uint16
bcdDevice uint16 // 0x100
iManufacturer uint8
iProduct uint8
iSerialNumber uint8
bNumConfigurations uint8
}
// NewDeviceDescriptor returns a USB DeviceDescriptor.
func NewDeviceDescriptor(class, subClass, proto, packetSize0 uint8, vid, pid, version uint16, im, ip, is, configs uint8) DeviceDescriptor {
return DeviceDescriptor{deviceDescriptorSize, 1, 0x200, class, subClass, proto, packetSize0, vid, pid, version, im, ip, is, configs}
}
// Bytes returns DeviceDescriptor data
func (d DeviceDescriptor) Bytes() [deviceDescriptorSize]byte {
var b [deviceDescriptorSize]byte
b[0] = byte(d.bLength)
b[1] = byte(d.bDescriptorType)
b[2] = byte(d.bcdUSB)
b[3] = byte(d.bcdUSB >> 8)
b[4] = byte(d.bDeviceClass)
b[5] = byte(d.bDeviceSubClass)
b[6] = byte(d.bDeviceProtocol)
b[7] = byte(d.bMaxPacketSize0)
b[8] = byte(d.idVendor)
b[9] = byte(d.idVendor >> 8)
b[10] = byte(d.idProduct)
b[11] = byte(d.idProduct >> 8)
b[12] = byte(d.bcdDevice)
b[13] = byte(d.bcdDevice >> 8)
b[14] = byte(d.iManufacturer)
b[15] = byte(d.iProduct)
b[16] = byte(d.iSerialNumber)
b[17] = byte(d.bNumConfigurations)
return b
}
const configDescriptorSize = 9
// ConfigDescriptor implements the standard USB configuration descriptor.
//
// Table 9-10. Standard Configuration Descriptor
// bLength, bDescriptorType, wTotalLength, bNumInterfaces, bConfigurationValue, iConfiguration
// bmAttributes, bMaxPower
//
type ConfigDescriptor struct {
bLength uint8 // 9
bDescriptorType uint8 // 2
wTotalLength uint16 // total length
bNumInterfaces uint8
bConfigurationValue uint8
iConfiguration uint8
bmAttributes uint8
bMaxPower uint8
}
// NewConfigDescriptor returns a new USB ConfigDescriptor.
func NewConfigDescriptor(totalLength uint16, interfaces uint8) ConfigDescriptor {
return ConfigDescriptor{configDescriptorSize, 2, totalLength, interfaces, 1, 0, usb_CONFIG_BUS_POWERED | usb_CONFIG_REMOTE_WAKEUP, 50}
}
// Bytes returns ConfigDescriptor data.
func (d ConfigDescriptor) Bytes() [configDescriptorSize]byte {
var b [configDescriptorSize]byte
b[0] = byte(d.bLength)
b[1] = byte(d.bDescriptorType)
b[2] = byte(d.wTotalLength)
b[3] = byte(d.wTotalLength >> 8)
b[4] = byte(d.bNumInterfaces)
b[5] = byte(d.bConfigurationValue)
b[6] = byte(d.iConfiguration)
b[7] = byte(d.bmAttributes)
b[8] = byte(d.bMaxPower)
return b
}
const interfaceDescriptorSize = 9
// InterfaceDescriptor implements the standard USB interface descriptor.
//
// Table 9-12. Standard Interface Descriptor
// bLength, bDescriptorType, bInterfaceNumber, bAlternateSetting, bNumEndpoints, bInterfaceClass,
// bInterfaceSubClass, bInterfaceProtocol, iInterface
//
type InterfaceDescriptor struct {
bLength uint8 // 9
bDescriptorType uint8 // 4
bInterfaceNumber uint8
bAlternateSetting uint8
bNumEndpoints uint8
bInterfaceClass uint8
bInterfaceSubClass uint8
bInterfaceProtocol uint8
iInterface uint8
}
// NewInterfaceDescriptor returns a new USB InterfaceDescriptor.
func NewInterfaceDescriptor(n, numEndpoints, class, subClass, protocol uint8) InterfaceDescriptor {
return InterfaceDescriptor{interfaceDescriptorSize, 4, n, 0, numEndpoints, class, subClass, protocol, 0}
}
// Bytes returns InterfaceDescriptor data.
func (d InterfaceDescriptor) Bytes() [interfaceDescriptorSize]byte {
var b [interfaceDescriptorSize]byte
b[0] = byte(d.bLength)
b[1] = byte(d.bDescriptorType)
b[2] = byte(d.bInterfaceNumber)
b[3] = byte(d.bAlternateSetting)
b[4] = byte(d.bNumEndpoints)
b[5] = byte(d.bInterfaceClass)
b[6] = byte(d.bInterfaceSubClass)
b[7] = byte(d.bInterfaceProtocol)
b[8] = byte(d.iInterface)
return b
}
const endpointDescriptorSize = 7
// EndpointDescriptor implements the standard USB endpoint descriptor.
//
// Table 9-13. Standard Endpoint Descriptor
// bLength, bDescriptorType, bEndpointAddress, bmAttributes, wMaxPacketSize, bInterval
//
type EndpointDescriptor struct {
bLength uint8 // 7
bDescriptorType uint8 // 5
bEndpointAddress uint8
bmAttributes uint8
wMaxPacketSize uint16
bInterval uint8
}
// NewEndpointDescriptor returns a new USB EndpointDescriptor.
func NewEndpointDescriptor(addr, attr uint8, packetSize uint16, interval uint8) EndpointDescriptor {
return EndpointDescriptor{endpointDescriptorSize, 5, addr, attr, packetSize, interval}
}
// Bytes returns EndpointDescriptor data.
func (d EndpointDescriptor) Bytes() [endpointDescriptorSize]byte {
var b [endpointDescriptorSize]byte
b[0] = byte(d.bLength)
b[1] = byte(d.bDescriptorType)
b[2] = byte(d.bEndpointAddress)
b[3] = byte(d.bmAttributes)
b[4] = byte(d.wMaxPacketSize)
b[5] = byte(d.wMaxPacketSize >> 8)
b[6] = byte(d.bInterval)
return b
}
const iadDescriptorSize = 8
// IADDescriptor is an Interface Association Descriptor, which is used
// to bind 2 interfaces together in CDC composite device.
//
// Standard Interface Association Descriptor:
// bLength, bDescriptorType, bFirstInterface, bInterfaceCount, bFunctionClass, bFunctionSubClass,
// bFunctionProtocol, iFunction
//
type IADDescriptor struct {
bLength uint8 // 8
bDescriptorType uint8 // 11
bFirstInterface uint8
bInterfaceCount uint8
bFunctionClass uint8
bFunctionSubClass uint8
bFunctionProtocol uint8
iFunction uint8
}
// NewIADDescriptor returns a new USB IADDescriptor.
func NewIADDescriptor(firstInterface, count, class, subClass, protocol uint8) IADDescriptor {
return IADDescriptor{iadDescriptorSize, 11, firstInterface, count, class, subClass, protocol, 0}
}
// Bytes returns IADDescriptor data.
func (d IADDescriptor) Bytes() [iadDescriptorSize]byte {
var b [iadDescriptorSize]byte
b[0] = byte(d.bLength)
b[1] = byte(d.bDescriptorType)
b[2] = byte(d.bFirstInterface)
b[3] = byte(d.bInterfaceCount)
b[4] = byte(d.bFunctionClass)
b[5] = byte(d.bFunctionSubClass)
b[6] = byte(d.bFunctionProtocol)
b[7] = byte(d.iFunction)
return b
}
const cdcCSInterfaceDescriptorSize = 5
// CDCCSInterfaceDescriptor is a CDC CS interface descriptor.
type CDCCSInterfaceDescriptor struct {
len uint8 // 5
dtype uint8 // 0x24
subtype uint8
d0 uint8
d1 uint8
}
// NewCDCCSInterfaceDescriptor returns a new USB CDCCSInterfaceDescriptor.
func NewCDCCSInterfaceDescriptor(subtype, d0, d1 uint8) CDCCSInterfaceDescriptor {
return CDCCSInterfaceDescriptor{cdcCSInterfaceDescriptorSize, 0x24, subtype, d0, d1}
}
// Bytes returns CDCCSInterfaceDescriptor data.
func (d CDCCSInterfaceDescriptor) Bytes() [cdcCSInterfaceDescriptorSize]byte {
var b [cdcCSInterfaceDescriptorSize]byte
b[0] = byte(d.len)
b[1] = byte(d.dtype)
b[2] = byte(d.subtype)
b[3] = byte(d.d0)
b[4] = byte(d.d1)
return b
}
const cmFunctionalDescriptorSize = 5
// CMFunctionalDescriptor is the functional descriptor general format.
type CMFunctionalDescriptor struct {
bFunctionLength uint8
bDescriptorType uint8 // 0x24
bDescriptorSubtype uint8 // 1
bmCapabilities uint8
bDataInterface uint8
}
// NewCMFunctionalDescriptor returns a new USB CMFunctionalDescriptor.
func NewCMFunctionalDescriptor(subtype, d0, d1 uint8) CMFunctionalDescriptor {
return CMFunctionalDescriptor{5, 0x24, subtype, d0, d1}
}
// Bytes returns the CMFunctionalDescriptor data.
func (d CMFunctionalDescriptor) Bytes() [cmFunctionalDescriptorSize]byte {
var b [cmFunctionalDescriptorSize]byte
b[0] = byte(d.bFunctionLength)
b[1] = byte(d.bDescriptorType)
b[2] = byte(d.bDescriptorSubtype)
b[3] = byte(d.bmCapabilities)
b[4] = byte(d.bDescriptorSubtype)
return b
}
const acmFunctionalDescriptorSize = 4
// ACMFunctionalDescriptor is a Abstract Control Model (ACM) USB descriptor.
type ACMFunctionalDescriptor struct {
len uint8
dtype uint8 // 0x24
subtype uint8 // 1
bmCapabilities uint8
}
// NewACMFunctionalDescriptor returns a new USB ACMFunctionalDescriptor.
func NewACMFunctionalDescriptor(subtype, d0 uint8) ACMFunctionalDescriptor {
return ACMFunctionalDescriptor{4, 0x24, subtype, d0}
}
// Bytes returns the ACMFunctionalDescriptor data.
func (d ACMFunctionalDescriptor) Bytes() [acmFunctionalDescriptorSize]byte {
var b [acmFunctionalDescriptorSize]byte
b[0] = byte(d.len)
b[1] = byte(d.dtype)
b[2] = byte(d.subtype)
b[3] = byte(d.bmCapabilities)
return b
}
// CDCDescriptor is the Communication Device Class (CDC) descriptor.
type CDCDescriptor struct {
// IAD
iad IADDescriptor // Only needed on compound device
// Control
cif InterfaceDescriptor
header CDCCSInterfaceDescriptor
// CDC control
controlManagement ACMFunctionalDescriptor // ACM
functionalDescriptor CDCCSInterfaceDescriptor // CDC_UNION
callManagement CMFunctionalDescriptor // Call Management
cifin EndpointDescriptor
// CDC Data
dif InterfaceDescriptor
in EndpointDescriptor
out EndpointDescriptor
}
func NewCDCDescriptor(i IADDescriptor, c InterfaceDescriptor,
h CDCCSInterfaceDescriptor,
cm ACMFunctionalDescriptor,
fd CDCCSInterfaceDescriptor,
callm CMFunctionalDescriptor,
ci EndpointDescriptor,
di InterfaceDescriptor,
outp EndpointDescriptor,
inp EndpointDescriptor) CDCDescriptor {
return CDCDescriptor{iad: i,
cif: c,
header: h,
controlManagement: cm,
functionalDescriptor: fd,
callManagement: callm,
cifin: ci,
dif: di,
in: inp,
out: outp}
}
const cdcSize = iadDescriptorSize +
interfaceDescriptorSize +
cdcCSInterfaceDescriptorSize +
acmFunctionalDescriptorSize +
cdcCSInterfaceDescriptorSize +
cmFunctionalDescriptorSize +
endpointDescriptorSize +
interfaceDescriptorSize +
endpointDescriptorSize +
endpointDescriptorSize
// Bytes returns CDCDescriptor data.
func (d CDCDescriptor) Bytes() [cdcSize]byte {
var b [cdcSize]byte
offset := 0
iad := d.iad.Bytes()
copy(b[offset:], iad[:])
offset += len(iad)
cif := d.cif.Bytes()
copy(b[offset:], cif[:])
offset += len(cif)
header := d.header.Bytes()
copy(b[offset:], header[:])
offset += len(header)
controlManagement := d.controlManagement.Bytes()
copy(b[offset:], controlManagement[:])
offset += len(controlManagement)
functionalDescriptor := d.functionalDescriptor.Bytes()
copy(b[offset:], functionalDescriptor[:])
offset += len(functionalDescriptor)
callManagement := d.callManagement.Bytes()
copy(b[offset:], callManagement[:])
offset += len(callManagement)
cifin := d.cifin.Bytes()
copy(b[offset:], cifin[:])
offset += len(cifin)
dif := d.dif.Bytes()
copy(b[offset:], dif[:])
offset += len(dif)
out := d.out.Bytes()
copy(b[offset:], out[:])
offset += len(out)
in := d.in.Bytes()
copy(b[offset:], in[:])
offset += len(in)
return b
}
// MSCDescriptor is not used yet.
type MSCDescriptor struct {
msc InterfaceDescriptor
in EndpointDescriptor
out EndpointDescriptor
}
const cdcLineInfoSize = 7
type cdcLineInfo struct {
dwDTERate uint32
bCharFormat uint8
bParityType uint8
bDataBits uint8
lineState uint8
}
// strToUTF16LEDescriptor converts a utf8 string into a string descriptor
// note: the following code only converts ascii characters to UTF16LE. In order
// to do a "proper" conversion, we would need to pull in the 'unicode/utf16'
// package, which at the time this was written added 512 bytes to the compiled
// binary.
func strToUTF16LEDescriptor(in string, out []byte) {
out[0] = byte(len(out))
out[1] = usb_STRING_DESCRIPTOR_TYPE
for i, rune := range in {
out[(i<<1)+2] = byte(rune)
out[(i<<1)+3] = 0
}
return
}
var (
// TODO: allow setting these
usb_STRING_LANGUAGE = [2]uint16{(3 << 8) | (2 + 2), 0x0409} // English
)
const (
usb_IMANUFACTURER = 1
usb_IPRODUCT = 2
usb_ISERIAL = 3
usb_ENDPOINT_TYPE_CONTROL = 0x00
usb_ENDPOINT_TYPE_ISOCHRONOUS = 0x01
usb_ENDPOINT_TYPE_BULK = 0x02
usb_ENDPOINT_TYPE_INTERRUPT = 0x03
usb_DEVICE_DESCRIPTOR_TYPE = 1
usb_CONFIGURATION_DESCRIPTOR_TYPE = 2
usb_STRING_DESCRIPTOR_TYPE = 3
usb_INTERFACE_DESCRIPTOR_TYPE = 4
usb_ENDPOINT_DESCRIPTOR_TYPE = 5
usb_DEVICE_QUALIFIER = 6
usb_OTHER_SPEED_CONFIGURATION = 7
usbEndpointOut = 0x00
usbEndpointIn = 0x80
usbEndpointPacketSize = 64 // 64 for Full Speed, EPT size max is 1024
usb_EPT_NUM = 7
// standard requests
usb_GET_STATUS = 0
usb_CLEAR_FEATURE = 1
usb_SET_FEATURE = 3
usb_SET_ADDRESS = 5
usb_GET_DESCRIPTOR = 6
usb_SET_DESCRIPTOR = 7
usb_GET_CONFIGURATION = 8
usb_SET_CONFIGURATION = 9
usb_GET_INTERFACE = 10
usb_SET_INTERFACE = 11
usb_DEVICE_CLASS_COMMUNICATIONS = 0x02
usb_DEVICE_CLASS_HUMAN_INTERFACE = 0x03
usb_DEVICE_CLASS_STORAGE = 0x08
usb_DEVICE_CLASS_VENDOR_SPECIFIC = 0xFF
usb_CONFIG_POWERED_MASK = 0x40
usb_CONFIG_BUS_POWERED = 0x80
usb_CONFIG_SELF_POWERED = 0xC0
usb_CONFIG_REMOTE_WAKEUP = 0x20
// CDC
usb_CDC_ACM_INTERFACE = 0 // CDC ACM
usb_CDC_DATA_INTERFACE = 1 // CDC Data
usb_CDC_FIRST_ENDPOINT = 1
usb_CDC_ENDPOINT_ACM = 1
usb_CDC_ENDPOINT_OUT = 2
usb_CDC_ENDPOINT_IN = 3
// bmRequestType
usb_REQUEST_HOSTTODEVICE = 0x00
usb_REQUEST_DEVICETOHOST = 0x80
usb_REQUEST_DIRECTION = 0x80
usb_REQUEST_STANDARD = 0x00
usb_REQUEST_CLASS = 0x20
usb_REQUEST_VENDOR = 0x40
usb_REQUEST_TYPE = 0x60
usb_REQUEST_DEVICE = 0x00
usb_REQUEST_INTERFACE = 0x01
usb_REQUEST_ENDPOINT = 0x02
usb_REQUEST_OTHER = 0x03
usb_REQUEST_RECIPIENT = 0x1F
usb_REQUEST_DEVICETOHOST_CLASS_INTERFACE = (usb_REQUEST_DEVICETOHOST | usb_REQUEST_CLASS | usb_REQUEST_INTERFACE)
usb_REQUEST_HOSTTODEVICE_CLASS_INTERFACE = (usb_REQUEST_HOSTTODEVICE | usb_REQUEST_CLASS | usb_REQUEST_INTERFACE)
usb_REQUEST_DEVICETOHOST_STANDARD_INTERFACE = (usb_REQUEST_DEVICETOHOST | usb_REQUEST_STANDARD | usb_REQUEST_INTERFACE)
// CDC Class requests
usb_CDC_SET_LINE_CODING = 0x20
usb_CDC_GET_LINE_CODING = 0x21
usb_CDC_SET_CONTROL_LINE_STATE = 0x22
usb_CDC_SEND_BREAK = 0x23
usb_CDC_V1_10 = 0x0110
usb_CDC_COMMUNICATION_INTERFACE_CLASS = 0x02
usb_CDC_CALL_MANAGEMENT = 0x01
usb_CDC_ABSTRACT_CONTROL_MODEL = 0x02
usb_CDC_HEADER = 0x00
usb_CDC_ABSTRACT_CONTROL_MANAGEMENT = 0x02
usb_CDC_UNION = 0x06
usb_CDC_CS_INTERFACE = 0x24
usb_CDC_CS_ENDPOINT = 0x25
usb_CDC_DATA_INTERFACE_CLASS = 0x0A
usb_CDC_LINESTATE_DTR = 0x01
usb_CDC_LINESTATE_RTS = 0x02
)
// usbDeviceDescBank is the USB device endpoint descriptor.
// typedef struct {
// __IO USB_DEVICE_ADDR_Type ADDR; /**< \brief Offset: 0x000 (R/W 32) DEVICE_DESC_BANK Endpoint Bank, Adress of Data Buffer */
// __IO USB_DEVICE_PCKSIZE_Type PCKSIZE; /**< \brief Offset: 0x004 (R/W 32) DEVICE_DESC_BANK Endpoint Bank, Packet Size */
// __IO USB_DEVICE_EXTREG_Type EXTREG; /**< \brief Offset: 0x008 (R/W 16) DEVICE_DESC_BANK Endpoint Bank, Extended */
// __IO USB_DEVICE_STATUS_BK_Type STATUS_BK; /**< \brief Offset: 0x00A (R/W 8) DEVICE_DESC_BANK Enpoint Bank, Status of Bank */
// RoReg8 Reserved1[0x5];
// } UsbDeviceDescBank;
type usbDeviceDescBank struct {
ADDR volatile.Register32
PCKSIZE volatile.Register32
EXTREG volatile.Register16
STATUS_BK volatile.Register8
_reserved [5]volatile.Register8
}
type usbDeviceDescriptor struct {
DeviceDescBank [2]usbDeviceDescBank
}
// typedef struct {
// union {
// uint8_t bmRequestType;
// struct {
// uint8_t direction : 5;
// uint8_t type : 2;
// uint8_t transferDirection : 1;
// };
// };
// uint8_t bRequest;
// uint8_t wValueL;
// uint8_t wValueH;
// uint16_t wIndex;
// uint16_t wLength;
// } USBSetup;
type usbSetup struct {
bmRequestType uint8
bRequest uint8
wValueL uint8
wValueH uint8
wIndex uint16
wLength uint16
}
func newUSBSetup(data []byte) usbSetup {
u := usbSetup{}
u.bmRequestType = uint8(data[0])
u.bRequest = uint8(data[1])
u.wValueL = uint8(data[2])
u.wValueH = uint8(data[3])
u.wIndex = uint16(data[4]) | (uint16(data[5]) << 8)
u.wLength = uint16(data[6]) | (uint16(data[7]) << 8)
return u
}
// USBCDC is the serial interface that works over the USB port.
// To implement the USBCDC interface for a board, you must declare a concrete type as follows:
//
// type USBCDC struct {
// Buffer *RingBuffer
// }
//
// You can also add additional members to this struct depending on your implementation,
// but the *RingBuffer is required.
// When you are declaring the USBCDC for your board, make sure that you also declare the
// RingBuffer using the NewRingBuffer() function:
//
// USBCDC{Buffer: NewRingBuffer()}
//
// Read from the RX buffer.
func (usbcdc USBCDC) Read(data []byte) (n int, err error) {
// check if RX buffer is empty
size := usbcdc.Buffered()
if size == 0 {
return 0, nil
}
// Make sure we do not read more from buffer than the data slice can hold.
if len(data) < size {
size = len(data)
}
// only read number of bytes used from buffer
for i := 0; i < size; i++ {
v, _ := usbcdc.ReadByte()
data[i] = v
}
return size, nil
}
// Write data to the USBCDC.
func (usbcdc USBCDC) Write(data []byte) (n int, err error) {
for _, v := range data {
usbcdc.WriteByte(v)
}
return len(data), nil
}
// ReadByte reads a single byte from the RX buffer.
// If there is no data in the buffer, returns an error.
func (usbcdc USBCDC) ReadByte() (byte, error) {
// check if RX buffer is empty
buf, ok := usbcdc.Buffer.Get()
if !ok {
return 0, errUSBCDCBufferEmpty
}
return buf, nil
}
// Buffered returns the number of bytes currently stored in the RX buffer.
func (usbcdc USBCDC) Buffered() int {
return int(usbcdc.Buffer.Used())
}
// Receive handles adding data to the UART's data buffer.
// Usually called by the IRQ handler for a machine.
func (usbcdc USBCDC) Receive(data byte) {
usbcdc.Buffer.Put(data)
}
// sendDescriptor creates and sends the various USB descriptor types that
// can be requested by the host.
func sendDescriptor(setup usbSetup) {
switch setup.wValueH {
case usb_CONFIGURATION_DESCRIPTOR_TYPE:
sendConfiguration(setup)
return
case usb_DEVICE_DESCRIPTOR_TYPE:
// composite descriptor
dd := NewDeviceDescriptor(0xef, 0x02, 0x01, 64, usb_VID, usb_PID, 0x100, usb_IMANUFACTURER, usb_IPRODUCT, usb_ISERIAL, 1)
l := deviceDescriptorSize
if setup.wLength < deviceDescriptorSize {
l = int(setup.wLength)
}
buf := dd.Bytes()
sendUSBPacket(0, buf[:l])
return
case usb_STRING_DESCRIPTOR_TYPE:
switch setup.wValueL {
case 0:
b := []byte{0x04, 0x03, 0x09, 0x04}
sendUSBPacket(0, b)
case usb_IPRODUCT:
b := make([]byte, (len(usb_STRING_PRODUCT)<<1)+2)
strToUTF16LEDescriptor(usb_STRING_PRODUCT, b)
sendUSBPacket(0, b)
case usb_IMANUFACTURER:
b := make([]byte, (len(usb_STRING_MANUFACTURER)<<1)+2)
strToUTF16LEDescriptor(usb_STRING_MANUFACTURER, b)
sendUSBPacket(0, b)
case usb_ISERIAL:
// TODO: allow returning a product serial number
sendZlp()
}
return
}
// do not know how to handle this message, so return zero
sendZlp()
return
}
// sendConfiguration creates and sends the configuration packet to the host.
func sendConfiguration(setup usbSetup) {
if setup.wLength == 9 {
sz := uint16(configDescriptorSize + cdcSize)
config := NewConfigDescriptor(sz, 2)
configBuf := config.Bytes()
sendUSBPacket(0, configBuf[:])
} else {
iad := NewIADDescriptor(0, 2, usb_CDC_COMMUNICATION_INTERFACE_CLASS, usb_CDC_ABSTRACT_CONTROL_MODEL, 0)
cif := NewInterfaceDescriptor(usb_CDC_ACM_INTERFACE, 1, usb_CDC_COMMUNICATION_INTERFACE_CLASS, usb_CDC_ABSTRACT_CONTROL_MODEL, 0)
header := NewCDCCSInterfaceDescriptor(usb_CDC_HEADER, usb_CDC_V1_10&0xFF, (usb_CDC_V1_10>>8)&0x0FF)
controlManagement := NewACMFunctionalDescriptor(usb_CDC_ABSTRACT_CONTROL_MANAGEMENT, 6)
functionalDescriptor := NewCDCCSInterfaceDescriptor(usb_CDC_UNION, usb_CDC_ACM_INTERFACE, usb_CDC_DATA_INTERFACE)
callManagement := NewCMFunctionalDescriptor(usb_CDC_CALL_MANAGEMENT, 1, 1)
cifin := NewEndpointDescriptor((usb_CDC_ENDPOINT_ACM | usbEndpointIn), usb_ENDPOINT_TYPE_INTERRUPT, 0x10, 0x10)
dif := NewInterfaceDescriptor(usb_CDC_DATA_INTERFACE, 2, usb_CDC_DATA_INTERFACE_CLASS, 0, 0)
out := NewEndpointDescriptor((usb_CDC_ENDPOINT_OUT | usbEndpointOut), usb_ENDPOINT_TYPE_BULK, usbEndpointPacketSize, 0)
in := NewEndpointDescriptor((usb_CDC_ENDPOINT_IN | usbEndpointIn), usb_ENDPOINT_TYPE_BULK, usbEndpointPacketSize, 0)
cdc := NewCDCDescriptor(iad,
cif,
header,
controlManagement,
functionalDescriptor,
callManagement,
cifin,
dif,
out,
in)
sz := uint16(configDescriptorSize + cdcSize)
config := NewConfigDescriptor(sz, 2)
configBuf := config.Bytes()
cdcBuf := cdc.Bytes()
var buf [configDescriptorSize + cdcSize]byte
copy(buf[0:], configBuf[:])
copy(buf[configDescriptorSize:], cdcBuf[:])
sendUSBPacket(0, buf[:])
}
}