drivers: audio: dmic: Add support for nRF PDM peripherals

Add a shim that allows using the nrfx PDM driver via the Zephyr API.
Add also missing devicetree nodes representing the PDM peripherals
in the nRF52 Series SoCs.
Extend the "nordic,nrf-pdm" binding with a new property that allows
specifying the clock source to be used by the PDM peripheral (so that
it is possible to use HFXO for better accuracy of the peripheral clock
or, in the nRF53 Series SoCs, to use the dedicated audio oscillator).

Signed-off-by: Andrzej Głąbek <[email protected]>

Author: anangl

CODEOWNERS

@@ -190,6 +190,7 @@
 /drivers/*/*andes*                        @cwshu @Teng-Shih-Wei
 /drivers/adc/                             @anangl
 /drivers/adc/adc_stm32.c                  @cybertale
+/drivers/audio/*nrfx*                     @anangl
 /drivers/bbram/*                          @yperess @sjg20 @jackrosenthal
 /drivers/bluetooth/                       @joerchan @jhedberg @Vudentz
 /drivers/cache/                           @carlocaione

drivers/audio/CMakeLists.txt

@@ -15,3 +15,4 @@ zephyr_library_sources_ifdef(CONFIG_AUDIO_INTEL_DMIC	decimation/pdm_decim_int32_
 zephyr_library_sources_ifdef(CONFIG_AUDIO_INTEL_DMIC	decimation/pdm_decim_table.c)
 zephyr_library_sources_ifdef(CONFIG_AUDIO_MPXXDTYY	mpxxdtyy.c)
 zephyr_library_sources_ifdef(CONFIG_AUDIO_MPXXDTYY	mpxxdtyy-i2s.c)
+zephyr_library_sources_ifdef(CONFIG_AUDIO_DMIC_NRFX_PDM	dmic_nrfx_pdm.c)

drivers/audio/Kconfig

@@ -52,6 +52,7 @@ source "subsys/logging/Kconfig.template.log_config"
 
 source "drivers/audio/Kconfig.intel_dmic"
 source "drivers/audio/Kconfig.mpxxdtyy"
+source "drivers/audio/Kconfig.dmic_pdm_nrfx"
 
 endif # AUDIO_DMIC
 

drivers/audio/Kconfig.dmic_pdm_nrfx

@@ -0,0 +1,13 @@
+# Copyright (c) 2021 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+# Workaround for not being able to have commas in macro arguments
+DT_COMPAT_NORDIC_NRF_PDM := nordic,nrf-pdm
+
+config AUDIO_DMIC_NRFX_PDM
+	bool "nRF PDM nrfx driver"
+	depends on $(dt_compat_enabled,$(DT_COMPAT_NORDIC_NRF_PDM))
+	default y
+	select NRFX_PDM
+	help
+	  Enable support for nrfx PDM driver for nRF MCU series.