ASoC: nau8822: add speaker Bridge Tied Output

Merge series from Francesco Dolcini <francesco@dolcini.it>:

Add support for BTL (Bridge Tied Load) configuration to NAU8822 audio codec,
since this requires adding a new property to the binding convert it from
txt to yaml first.

Documentation/devicetree/bindings/sound/nau8822.txt

-NAU8822 audio CODEC
-
-This device supports I2C only.
-
-Required properties:
-
-  - compatible : "nuvoton,nau8822"
-
-  - reg : the I2C address of the device.
-
-Example:
-
-codec: nau8822@1a {
-	compatible = "nuvoton,nau8822";
-	reg = <0x1a>;
-};

Documentation/devicetree/bindings/sound/nuvoton,nau8822.yaml

+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/sound/nuvoton,nau8822.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NAU8822 audio CODEC
+
+description: |
+  24 bit stereo audio codec with speaker driver.
+  This device supports I2C/SPI.
+
+maintainers:
+  - David Lin <CTLIN0@nuvoton.com>
+
+properties:
+  compatible:
+    enum:
+      - nuvoton,nau8822
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        codec@1a {
+            compatible = "nuvoton,nau8822";
+            reg = <0x1a>;
+        };
+    };

sound/soc/codecs/nau8822.c

@@ -1056,6 +1056,7 @@ static const int update_reg[] = {
 static int nau8822_probe(struct snd_soc_component *component)
 {
 	int i;
+	struct device_node *of_node = component->dev->of_node;
 
 	/*
 	 * Set the update bit in all registers, that have one. This way all
@@ -1066,6 +1067,14 @@ static int nau8822_probe(struct snd_soc_component *component)
 		snd_soc_component_update_bits(component,
 			update_reg[i], 0x100, 0x100);
 
+	/* Check property to configure the two loudspeaker outputs as
+	 * a single Bridge Tied Load output
+	 */
+	if (of_property_read_bool(of_node, "nuvoton,spk-btl"))
+		snd_soc_component_update_bits(component,
+					      NAU8822_REG_RIGHT_SPEAKER_CONTROL,
+					      NAU8822_RSUBBYP, NAU8822_RSUBBYP);
+
 	return 0;
 }
 

sound/soc/codecs/nau8822.h

@@ -187,6 +187,15 @@
 /* NAU8822_REG_PLL_K3 (0x27) */
 #define NAU8822_PLLK3_MASK			0x1FF
 
+/* NAU8822_REG_RIGHT_SPEAKER_CONTROL (0x2B) */
+#define NAU8822_RMIXMUT				0x20
+#define NAU8822_RSUBBYP				0x10
+
+#define NAU8822_RAUXRSUBG_SFT			1
+#define NAU8822_RAUXRSUBG_MASK			0x0E
+
+#define NAU8822_RAUXSMUT			0x01
+
 /* System Clock Source */
 enum {
 	NAU8822_CLK_MCLK,