ASoC platform driver for Apple MCA

Merge series from Martin Povišer <povik+lin@cutebit.org>:

sending what should be the final touches on Apple MCA driver. It most
likely goes without saying but please do not merge the DT additions
into the ASoC tree.

Documentation/devicetree/bindings/sound/apple,mca.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/sound/apple,mca.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple MCA I2S transceiver
+
+description: |
+  MCA is an I2S transceiver peripheral found on M1 and other Apple chips. It is
+  composed of a number of identical clusters which can operate independently
+  or in an interlinked fashion. Up to 6 clusters have been seen on an MCA.
+
+maintainers:
+  - Martin Povišer <povik+lin@cutebit.org>
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - apple,t6000-mca
+          - apple,t8103-mca
+      - const: apple,mca
+
+  reg:
+    items:
+      - description: Register region of the MCA clusters proper
+      - description: Register region of the DMA glue and its FIFOs
+
+  interrupts:
+    minItems: 4
+    maxItems: 6
+    description:
+      One interrupt per each cluster
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+  dmas:
+    minItems: 16
+    maxItems: 24
+    description:
+      DMA channels corresponding to the SERDES units in the peripheral. They are
+      listed in groups of four per cluster, and within the group they are given
+      as associated to the TXA, RXA, TXB, RXB units.
+
+  dma-names:
+    minItems: 16
+    items:
+      - const: tx0a
+      - const: rx0a
+      - const: tx0b
+      - const: rx0b
+      - const: tx1a
+      - const: rx1a
+      - const: tx1b
+      - const: rx1b
+      - const: tx2a
+      - const: rx2a
+      - const: tx2b
+      - const: rx2b
+      - const: tx3a
+      - const: rx3a
+      - const: tx3b
+      - const: rx3b
+      - const: tx4a
+      - const: rx4a
+      - const: tx4b
+      - const: rx4b
+      - const: tx5a
+      - const: rx5a
+      - const: tx5b
+      - const: rx5b
+    description: |
+      Names for the DMA channels: 'tx'/'rx', then cluster number, then 'a'/'b'
+      based on the associated SERDES unit.
+
+  clocks:
+    minItems: 4
+    maxItems: 6
+    description:
+      Clusters' input reference clock.
+
+  resets:
+    maxItems: 1
+
+  power-domains:
+    minItems: 5
+    maxItems: 7
+    description:
+      First a general power domain for register access, then the power
+      domains of individual clusters for their operation.
+
+  '#sound-dai-cells':
+    const: 1
+
+required:
+  - compatible
+  - reg
+  - dmas
+  - dma-names
+  - clocks
+  - power-domains
+  - '#sound-dai-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    mca: i2s@9b600000 {
+      compatible = "apple,t6000-mca", "apple,mca";
+      reg = <0x9b600000 0x10000>,
+            <0x9b200000 0x20000>;
+
+      clocks = <&nco 0>, <&nco 1>, <&nco 2>, <&nco 3>;
+      power-domains = <&ps_audio_p>, <&ps_mca0>, <&ps_mca1>,
+                      <&ps_mca2>, <&ps_mca3>;
+      dmas = <&admac 0>, <&admac 1>, <&admac 2>, <&admac 3>,
+             <&admac 4>, <&admac 5>, <&admac 6>, <&admac 7>,
+             <&admac 8>, <&admac 9>, <&admac 10>, <&admac 11>,
+             <&admac 12>, <&admac 13>, <&admac 14>, <&admac 15>;
+      dma-names = "tx0a", "rx0a", "tx0b", "rx0b",
+                  "tx1a", "rx1a", "tx1b", "rx1b",
+                  "tx2a", "rx2a", "tx2b", "rx2b",
+                  "tx3a", "rx3a", "tx3b", "rx3b";
+
+      #sound-dai-cells = <1>;
+    };

MAINTAINERS

@@ -1899,6 +1899,14 @@ F:	include/dt-bindings/pinctrl/apple.h
 F:	include/linux/apple-mailbox.h
 F:	include/linux/soc/apple/*
 
+ARM/APPLE MACHINE SOUND DRIVERS
+M:	Martin Povišer <povik+lin@cutebit.org>
+L:	asahi@lists.linux.dev
+L:	alsa-devel@alsa-project.org (moderated for non-subscribers)
+S:	Maintained
+F:	Documentation/devicetree/bindings/sound/apple,*
+F:	drivers/sound/apple/*
+
 ARM/ARTPEC MACHINE SUPPORT
 M:	Jesper Nilsson <jesper.nilsson@axis.com>
 M:	Lars Persson <lars.persson@axis.com>

sound/soc/Kconfig

@@ -68,6 +68,7 @@ config SND_SOC_ACPI
 # All the supported SoCs
 source "sound/soc/adi/Kconfig"
 source "sound/soc/amd/Kconfig"
+source "sound/soc/apple/Kconfig"
 source "sound/soc/atmel/Kconfig"
 source "sound/soc/au1x/Kconfig"
 source "sound/soc/bcm/Kconfig"

sound/soc/Makefile

@@ -34,6 +34,7 @@ obj-$(CONFIG_SND_SOC_ACPI) += snd-soc-acpi.o
 obj-$(CONFIG_SND_SOC)	+= snd-soc-core.o
 obj-$(CONFIG_SND_SOC)	+= codecs/
 obj-$(CONFIG_SND_SOC)	+= generic/
+obj-$(CONFIG_SND_SOC)	+= apple/
 obj-$(CONFIG_SND_SOC)	+= adi/
 obj-$(CONFIG_SND_SOC)	+= amd/
 obj-$(CONFIG_SND_SOC)	+= atmel/

sound/soc/apple/Kconfig

+config SND_SOC_APPLE_MCA
+	tristate "Apple Silicon MCA driver"
+	depends on ARCH_APPLE || COMPILE_TEST
+	select SND_DMAENGINE_PCM
+	select COMMON_CLK
+	default ARCH_APPLE
+	help
+	  This option enables an ASoC platform driver for MCA peripherals found
+	  on Apple Silicon SoCs.

sound/soc/apple/Makefile

+snd-soc-apple-mca-objs	:= mca.o
+
+obj-$(CONFIG_SND_SOC_APPLE_MCA)	+= snd-soc-apple-mca.o