ASoC: dt-bindings: wm8904: Add DMIC, GPIO, MIC and EQ support

Add two properties to select the IN1L/DMICDAT1 and IN2R/DMICDAT2
functionality:
- wlf,in1l-as-dmicdat1
- wlf,in1r-as-dmicdat2

Add a property to describe the GPIO configuration registers, that can be
used to set the four multifunction pins:
- wlf,gpio-cfg

Add a property to describe the mic bias control registers:
- wlf,micbias-cfg

Add two properties to describe the Dynamic Range Controller (DRC),
allowing multiple named configurations where each config sets the 4 DRC
registers (R40-R43):
- wlf,drc-cfg-regs
- wlf,drc-cfg-names

Add three properties to describe the equalizer (ReTune Mobile), allowing
multiple named configurations (associated with a samplerate) that set
the 24 (R134-R157) EQ registers:
- wlf,retune-mobile-cfg-regs
- wlf,retune-mobile-cfg-hz
- wlf,retune-mobile-cfg-rates

The set of names and configurations for DRC and ReTune Mobile are
specified by system integrators. The names are exposed directly to
userspace as options that can be selected at runtime.

Adding the DRC and ReTune Mobile data to the DT eases the transition
from pdata, which has handled them this way for over a decade. The
parameters filled in here are almost certainly specific tuning for the
hardware so it makes sense to ship them with the hardware description.

Datasheet: https://statics.cirrus.com/pubs/proDatasheet/WM8904_Rev4.1.pdf
Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20250319142059.46692-4-francesco@dolcini.it
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Ernest Van Hoecke

Documentation/devicetree/bindings/sound/wlf,wm8904.yaml

@@ -38,6 +38,82 @@ properties:
   DCVDD-supply: true
   MICVDD-supply: true
 
+  wlf,in1l-as-dmicdat1:
+    type: boolean
+    description:
+      Use IN1L/DMICDAT1 as DMICDAT1, enabling the DMIC input path.
+      Can be used separately or together with wlf,in1r-as-dmicdat2.
+
+  wlf,in1r-as-dmicdat2:
+    type: boolean
+    description:
+      Use IN1R/DMICDAT2 as DMICDAT2, enabling the DMIC input path.
+      Can be used separately or together with wlf,in1l-as-dmicdat1.
+
+  wlf,gpio-cfg:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    minItems: 4
+    maxItems: 4
+    description:
+      Default register values for R121/122/123/124 (GPIO Control).
+      If any entry has the value 0xFFFF, the related register won't be set.
+    default: [0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF]
+
+  wlf,micbias-cfg:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    minItems: 2
+    maxItems: 2
+    description:
+      Default register values for R6/R7 (Mic Bias Control).
+    default: [0, 0]
+
+  wlf,drc-cfg-names:
+    $ref: /schemas/types.yaml#/definitions/string-array
+    description:
+      List of strings for the available DRC modes.
+      If absent, DRC is disabled.
+
+  wlf,drc-cfg-regs:
+    $ref: /schemas/types.yaml#/definitions/uint16-matrix
+    description:
+      Sets of default register values for R40/41/42/43 (DRC).
+      Each set corresponds to a DRC mode, so the number of sets should equal
+      the length of wlf,drc-cfg-names.
+      If absent, DRC is disabled.
+    items:
+      minItems: 4
+      maxItems: 4
+
+  wlf,retune-mobile-cfg-names:
+    $ref: /schemas/types.yaml#/definitions/non-unique-string-array
+    description:
+      List of strings for the available retune modes.
+      If absent, retune is disabled.
+
+  wlf,retune-mobile-cfg-hz:
+    description:
+      The list must be the same length as wlf,retune-mobile-cfg-names.
+      If absent, retune is disabled.
+
+  wlf,retune-mobile-cfg-regs:
+    $ref: /schemas/types.yaml#/definitions/uint16-matrix
+    description:
+      Sets of default register values for R134/.../157 (EQ).
+      Each set corresponds to a retune mode, so the number of sets should equal
+      the length of wlf,retune-mobile-cfg-names.
+      If absent, retune is disabled.
+    items:
+      minItems: 24
+      maxItems: 24
+
+dependencies:
+  wlf,drc-cfg-names: [ 'wlf,drc-cfg-regs' ]
+  wlf,drc-cfg-regs: [ 'wlf,drc-cfg-names' ]
+
+  wlf,retune-mobile-cfg-names: [ 'wlf,retune-mobile-cfg-hz', 'wlf,retune-mobile-cfg-regs' ]
+  wlf,retune-mobile-cfg-regs: [ 'wlf,retune-mobile-cfg-names', 'wlf,retune-mobile-cfg-hz' ]
+  wlf,retune-mobile-cfg-hz: [ 'wlf,retune-mobile-cfg-names', 'wlf,retune-mobile-cfg-regs' ]
+
 required:
   - compatible
   - reg
@@ -70,5 +146,58 @@ examples:
             DBVDD-supply = <&reg_1p8v>;
             DCVDD-supply = <&reg_1p8v>;
             MICVDD-supply = <&reg_1p8v>;
+
+            wlf,drc-cfg-names = "default", "peaklimiter", "tradition", "soft",
+                                "music";
+            /*
+             * Config registers per name, respectively:
+             * KNEE_IP = 0,   KNEE_OP = 0,     HI_COMP = 1,   LO_COMP = 1
+             * KNEE_IP = -24, KNEE_OP = -6,    HI_COMP = 1/4, LO_COMP = 1
+             * KNEE_IP = -42, KNEE_OP = -3,    HI_COMP = 0,   LO_COMP = 1
+             * KNEE_IP = -45, KNEE_OP = -9,    HI_COMP = 1/8, LO_COMP = 1
+             * KNEE_IP = -30, KNEE_OP = -10.5, HI_COMP = 1/4, LO_COMP = 1
+             */
+            wlf,drc-cfg-regs = /bits/ 16 <0x01af 0x3248 0x0000 0x0000>,
+                               /bits/ 16 <0x04af 0x324b 0x0010 0x0408>,
+                               /bits/ 16 <0x04af 0x324b 0x0028 0x0704>,
+                               /bits/ 16 <0x04af 0x324b 0x0018 0x078c>,
+                               /bits/ 16 <0x04af 0x324b 0x0010 0x050e>;
+
+            /* GPIO1 = DMIC_CLK, don't touch others */
+            wlf,gpio-cfg = <0x0018>, <0xffff>, <0xffff>, <0xffff>;
+
+            /* Use IN1R as DMICDAT2, leave IN1L as an analog input path */
+            wlf,in1r-as-dmicdat2;
+
+            wlf,retune-mobile-cfg-names = "bassboost", "bassboost", "treble";
+            wlf,retune-mobile-cfg-hz = <48000>, <44100>, <48000>;
+            /*
+             * Config registers per name, respectively:
+             * EQ_ENA,  100 Hz,  300 Hz,  875 Hz, 2400 Hz, 6900 Hz
+             *      1,   +6 dB,   +3 dB,    0 dB,    0 dB,    0 dB
+             *      1,   +6 dB,   +3 dB,    0 dB,    0 dB,    0 dB
+             *      1,   -2 dB,   -2 dB,    0 dB,    0 dB,   +3 dB
+             * Each one uses the defaults for ReTune Mobile registers 140-157
+             */
+            wlf,retune-mobile-cfg-regs = /bits/ 16 <0x1 0x12 0xf 0xc 0xc 0xc
+                                                    0x0fca 0x0400 0x00d8 0x1eb5
+                                                    0xf145 0x0bd5 0x0075 0x1c58
+                                                    0xf3d3 0x0a54 0x0568 0x168e
+                                                    0xf829 0x07ad 0x1103 0x0564
+                                                    0x0559 0x4000>,
+
+                                         /bits/ 16 <0x1 0x12 0xf 0xc 0xc 0xc
+                                                    0x0fca 0x0400 0x00d8 0x1eb5
+                                                    0xf145 0x0bd5 0x0075 0x1c58
+                                                    0xf3d3 0x0a54 0x0568 0x168e
+                                                    0xf829 0x07ad 0x1103 0x0564
+                                                    0x0559 0x4000>,
+
+                                         /bits/ 16 <0x1 0xa 0xa 0xc 0xc 0xf
+                                                    0x0fca 0x0400 0x00d8 0x1eb5
+                                                    0xf145 0x0bd5 0x0075 0x1c58
+                                                    0xf3d3 0x0a54 0x0568 0x168e
+                                                    0xf829 0x07ad 0x1103 0x0564
+                                                    0x0559 0x4000>;
         };
     };