machine/usb: refactoring descriptors into subpackage for modularity

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

src/machine/usb/descriptor/descriptor.go

@@ -0,0 +1,63 @@
+package descriptor
+
+import (
+	"runtime/volatile"
+)
+
+const (
+	TypeDevice                = 0x1
+	TypeConfiguration         = 0x2
+	TypeString                = 0x3
+	TypeInterface             = 0x4
+	TypeEndpoint              = 0x5
+	TypeDeviceQualifier       = 0x6
+	TypeInterfaceAssociation  = 0xb
+	TypeClassHID              = 0x21
+	TypeHIDReport             = 0x22
+	TypeClassSpecific         = 0x24
+	TypeClassSpecificEndpoint = 0x25
+)
+
+// DeviceDescBank is the USB device endpoint .
+type DeviceDescBank struct {
+	ADDR      volatile.Register32
+	PCKSIZE   volatile.Register32
+	EXTREG    volatile.Register16
+	STATUS_BK volatile.Register8
+	_reserved [5]volatile.Register8
+}
+
+type Device struct {
+	DeviceDescBank [2]DeviceDescBank
+}
+
+type Descriptor struct {
+	Device        []byte
+	Configuration []byte
+	HID           map[uint16][]byte
+}
+
+func (d *Descriptor) Configure(idVendor, idProduct uint16) {
+	dev := DeviceType{d.Device}
+	dev.VendorID(idVendor)
+	dev.ProductID(idProduct)
+
+	conf := ConfigurationType{d.Configuration}
+	conf.TotalLength(uint16(len(d.Configuration)))
+}
+
+func appendSlices[T any](slices [][]T) []T {
+	var size, pos int
+
+	for _, s := range slices {
+		size += len(s)
+	}
+
+	result := make([]T, size)
+
+	for _, s := range slices {
+		pos += copy(result[pos:], s)
+	}
+
+	return result
+}