drivers: audio: dmic: Add Apollo510 PDM driver for DMIC.

Add PDM driver for DMIC.
This driver is compatible with samples/audio/dmic application.

Signed-off-by: Lewis Lee <llee@ambiq.com>

Author: boostjw

boards/ambiq/apollo510_evb/apollo510_evb-pinctrl.dtsi

@@ -265,6 +265,13 @@
 		};
 	};
 
+	pdm0_default: pdm0_default {
+		group0 {
+			pinmux = <PDM0_CLK_P50>,
+				 <PDM0_DATA_P51>;
+		};
+	};
+
 	mspi0_default: mspi0_default {
 		group0 {
 			pinmux = <MSPI0_0_P64>,

boards/ambiq/apollo510_evb/apollo510_evb.dts

@@ -205,6 +205,12 @@ zephyr_udc0: &usb {
 	status = "okay";
 };
 
+&pdm0 {
+	pinctrl-0 = <&pdm0_default>;
+	pinctrl-names = "default";
+	status = "disabled";
+};
+
 &gpio0_31 {
 	status = "okay";
 };

boards/ambiq/apollo510_evb/apollo510_evb.yaml

@@ -19,6 +19,7 @@ supported:
   - hwinfo
   - clock_control
   - usbd
+  - pdm
   - mspi
 testing:
   ignore_tags:

drivers/audio/CMakeLists.txt

@@ -15,3 +15,4 @@ zephyr_library_sources_ifdef(CONFIG_AUDIO_CODEC_WM8962 wm8962.c)
 zephyr_library_sources_ifdef(CONFIG_AUDIO_CODEC_CS43L22 cs43l22.c)
 zephyr_library_sources_ifdef(CONFIG_AUDIO_CODEC_PCM1681 pcm1681.c)
 zephyr_library_sources_ifdef(CONFIG_AUDIO_CODEC_MAX98091 max98091.c)
+zephyr_library_sources_ifdef(CONFIG_AUDIO_DMIC_AMBIQ_PDM dmic_ambiq_pdm.c)

drivers/audio/Kconfig

@@ -66,6 +66,7 @@ source "subsys/logging/Kconfig.template.log_config"
 source "drivers/audio/Kconfig.mpxxdtyy"
 source "drivers/audio/Kconfig.dmic_pdm_nrfx"
 source "drivers/audio/Kconfig.dmic_mcux"
+source "drivers/audio/Kconfig.dmic_ambiq_pdm"
 
 endif # AUDIO_DMIC
 

drivers/audio/Kconfig.dmic_ambiq_pdm

@@ -0,0 +1,29 @@
+# Copyright (c) 2025 Ambiq Micro Inc.
+# SPDX-License-Identifier: Apache-2.0
+
+config AUDIO_DMIC_AMBIQ_PDM
+	bool "Ambiq PDM driver"
+	default y
+	depends on DT_HAS_AMBIQ_PDM_ENABLED
+	select AMBIQ_HAL
+	select AMBIQ_HAL_USE_PDM
+	select PINCTRL
+	help
+	  Enable support for Ambiq PDM driver for Apollo 5 MCU.
+
+if AUDIO_DMIC_AMBIQ_PDM
+
+config PDM_AMBIQ_HANDLE_CACHE
+	bool "Turn on cache handling in PDM driver"
+	default y
+	depends on CACHE_MANAGEMENT && DCACHE
+	help
+	  Disable this if cache has been handled in upper layers.
+
+config PDM_AMBIQ_BUFFER_ALIGNMENT
+	int "Set the PDM DMA TCB buffer alignment"
+	default DCACHE_LINE_SIZE if DCACHE
+	help
+	  PDM buffer should be 32bytes aligned when placed in cachable region.
+
+endif