machine/usb: refactoring descriptors into subpackage for modularity

Signed-off-by: deadprogram <ron@hybridgroup.com>

src/machine/usb/descriptor/interface.go

@@ -0,0 +1,49 @@
+package descriptor
+
+const (
+	interfaceTypeLen = 9
+)
+
+type InterfaceType struct {
+	data []byte
+}
+
+func (d InterfaceType) Bytes() []byte {
+	return d.data
+}
+
+func (d InterfaceType) Length(v uint8) {
+	d.data[0] = byte(v)
+}
+
+func (d InterfaceType) Type(v uint8) {
+	d.data[1] = byte(v)
+}
+
+func (d InterfaceType) InterfaceNumber(v uint8) {
+	d.data[2] = byte(v)
+}
+
+func (d InterfaceType) AlternateSetting(v uint8) {
+	d.data[3] = byte(v)
+}
+
+func (d InterfaceType) NumEndpoints(v uint8) {
+	d.data[4] = byte(v)
+}
+
+func (d InterfaceType) InterfaceClass(v uint8) {
+	d.data[5] = byte(v)
+}
+
+func (d InterfaceType) InterfaceSubClass(v uint8) {
+	d.data[6] = byte(v)
+}
+
+func (d InterfaceType) InterfaceProtocol(v uint8) {
+	d.data[7] = byte(v)
+}
+
+func (d InterfaceType) Interface(v uint8) {
+	d.data[8] = byte(v)
+}