[PATCH] ALSA: hda: dt-bindings: cix: add hda dma memory-region

[joakim.zhang@cixtech.com]

From: Joakim Zhang <joakim.zhang@cixtech.com>

Document the reserved memory region used for IPBLOQ HDA DMA buffers,
since the memory accessed by HDA DMA has certain limitations.

The property is optional: the controller driver falls back to system
memory when it is absent, but the limited region should be used when
the platform provides one.

Signed-off-by: Joakim Zhang <joakim.zhang@cixtech.com>
---
 .../devicetree/bindings/sound/cix,sky1-ipbloq-hda.yaml    | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/sound/cix,sky1-ipbloq-hda.yaml b/Documentation/devicetree/bindings/sound/cix,sky1-ipbloq-hda.yaml
index 02ac5f1aa926..045e1a517f6f 100644
--- a/Documentation/devicetree/bindings/sound/cix,sky1-ipbloq-hda.yaml
+++ b/Documentation/devicetree/bindings/sound/cix,sky1-ipbloq-hda.yaml
@@ -36,6 +36,13 @@ properties:
   resets:
     maxItems: 1
 
+  memory-region:
+    maxItems: 1
+    description: |
+      Reserved memory region used for HDA DMA buffers. The property is
+      optional; the controller driver falls back to system memory when
+      it is absent.
+
 required:
   - compatible
   - reg
@@ -59,4 +66,5 @@ examples:
         clock-names = "ipg", "per";
         resets = <&audss_rst 14>;
         model = "CIX SKY1 EVB HDA";
+        memory-region = <&audio_alsa_hda>;
     };
-- 
2.50.1