x86: Add bindings for NHLT

Add devicetree bindings for the Intel Non-High-Definition-Audio Link Table
(NHLT).

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/include/dt-bindings/sound/nhlt.h b/include/dt-bindings/sound/nhlt.h
new file mode 100644
index 0000000..dad69c2
--- /dev/null
+++ b/include/dt-bindings/sound/nhlt.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2019 Google LLC
+ */
+
+#ifndef _DT_BINDINGS_SOUND_NHLT_H
+#define _DT_BINDINGS_SOUND_NHLT_H
+
+/* See Table 2-1. NHLT Endpoint Descriptor in the NHLT Specification (0.8.1) */
+#define NHLT_VID	0x8086
+#define NHLT_DID_DMIC	0xae20
+#define NHLT_DID_BT	0xae30
+#define NHLT_DID_SSP	0xae34
+
+/* Hardware links available to use for codecs */
+#define AUDIO_LINK_SSP0		0
+#define AUDIO_LINK_SSP1		1
+#define AUDIO_LINK_SSP2		2
+#define AUDIO_LINK_SSP3		3
+#define AUDIO_LINK_SSP4		4
+#define AUDIO_LINK_SSP5		5
+#define AUDIO_LINK_DMIC		6
+
+#endif /* _DT_BINDINGS_SOUND_NHLT_H */