ASoC: apple: mca: Start new platform driver

Add ASoC platform driver for the MCA peripheral found on Apple M1 and
other chips.
Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Link: https://lore.kernel.org/r/20220824160715.95779-4-povik+lin@cutebit.orgSigned-off-by: Mark Brown <broonie@kernel.org>

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