machine/usb/hid: add MediaKey support (#3436)

machine/usb/hid: add MediaKey support

src/machine/usb/descriptor.go

@@ -67,7 +67,7 @@ var DescriptorCDCHID = Descriptor{
 		0x07, 0x05, 0x02, 0x02, 0x40, 0x00, 0x00,
 		0x07, 0x05, 0x83, 0x02, 0x40, 0x00, 0x00,
 		0x09, 0x04, 0x02, 0x00, 0x01, 0x03, 0x00, 0x00, 0x00,
-		0x09, 0x21, 0x01, 0x01, 0x00, 0x01, 0x22, 0x65, 0x00,
+		0x09, 0x21, 0x01, 0x01, 0x00, 0x01, 0x22, 0x7E, 0x00,
 		0x07, 0x05, 0x84, 0x03, 0x40, 0x00, 0x01,
 	},
 	HID: map[uint16][]byte{
@@ -80,6 +80,19 @@ var DescriptorCDCHID = Descriptor{
 			0x03, 0x15, 0x00, 0x25, 0x01, 0x95, 0x03, 0x75, 0x01, 0x81, 0x02, 0x95, 0x01, 0x75, 0x05, 0x81,
 			0x03, 0x05, 0x01, 0x09, 0x30, 0x09, 0x31, 0x09, 0x38, 0x15, 0x81, 0x25, 0x7f, 0x75, 0x08, 0x95,
 			0x03, 0x81, 0x06, 0xc0, 0xc0,
+
+			0x05, 0x0C, //       Usage Page (Consumer)
+			0x09, 0x01, //       Usage (Consumer Control)
+			0xA1, 0x01, //       Collection (Application)
+			0x85, 0x03, //         Report ID (3)
+			0x15, 0x00, //         Logical Minimum (0)
+			0x26, 0xFF, 0x1F, //   Logical Maximum (8191)
+			0x19, 0x00, //         Usage Minimum (Unassigned)
+			0x2A, 0xFF, 0x1F, //   Usage Maximum (0x1FFF)
+			0x75, 0x10, //         Report Size (16)
+			0x95, 0x01, //         Report Count (1)
+			0x81, 0x00, //         Input (Data,Array,Abs,No Wrap,Linear,Preferred State,No Null Position)
+			0xC0, //             End       Collection
 		},
 	},
 }

src/machine/usb/hid/keyboard/keyboard.go

@@ -238,7 +238,9 @@ func (kb *keyboard) sendKey(consumer bool, b []byte) bool {
 
 func (kb *keyboard) keyboardSendKeys(consumer bool) bool {
 	var b [9]byte
-	b[0] = 0x02
+
+	if !consumer {
+		b[0] = 0x02 // REPORT_ID
 		b[1] = kb.mod
 		b[2] = 0x02
 		b[3] = kb.key[0]
@@ -248,6 +250,14 @@ func (kb *keyboard) keyboardSendKeys(consumer bool) bool {
 		b[7] = kb.key[4]
 		b[8] = kb.key[5]
 		return kb.sendKey(consumer, b[:])
+
+	} else {
+		b[0] = 0x03 // REPORT_ID
+		b[1] = uint8(kb.con[0])
+		b[2] = uint8((kb.con[0] & 0x0300) >> 8)
+
+		return kb.sendKey(consumer, b[:3])
+	}
 }
 
 // Down transmits a key-down event for the given Keycode.

src/machine/usb/hid/keyboard/keycode.go

@@ -77,6 +77,7 @@ const (
 	KeyModifierRightAlt   Keycode = 0x40 | 0xE000
 	KeyModifierRightGUI   Keycode = 0x80 | 0xE000
 
+	// KeySystemXXX is not supported now
 	KeySystemPowerDown Keycode = 0x81 | 0xE200
 	KeySystemSleep     Keycode = 0x82 | 0xE200
 	KeySystemWakeUp    Keycode = 0x83 | 0xE200