[nrf fromlist] drivers: audio: dmic_nrfx: allow use of ACLK for nRF54L20

drivers/audio/dmic_nrfx_pdm.c

@@ -18,14 +18,23 @@ LOG_MODULE_REGISTER(dmic_nrfx_pdm, CONFIG_AUDIO_DMIC_LOG_LEVEL);
 #if CONFIG_SOC_SERIES_NRF54HX
 #define DMIC_NRFX_CLOCK_FREQ MHZ(16)
 #define DMIC_NRFX_CLOCK_FACTOR 8192
+#define DMIC_NRFX_AUDIO_CLOCK_FREQ DT_PROP_OR(DT_NODELABEL(audiopll), frequency, 0)
 #else
 #define DMIC_NRFX_CLOCK_FREQ MHZ(32)
 #define DMIC_NRFX_CLOCK_FACTOR 4096
+#define DMIC_NRFX_AUDIO_CLOCK_FREQ \
+	COND_CODE_1(CONFIG_SOC_NRF54L20, \
+		(DT_PROP_OR(DT_NODELABEL(aclk), clock_frequency, 0)), \
+		(DT_PROP_OR(DT_NODELABEL(clock), hfclkaudio_frequency, 0)))
 #endif
 
 struct dmic_nrfx_pdm_drv_data {
 	const nrfx_pdm_t *pdm;
+#if CONFIG_CLOCK_CONTROL_NRF
 	struct onoff_manager *clk_mgr;
+#elif CONFIG_CLOCK_CONTROL_NRF2_AUDIOPLL
+	const struct device *audiopll_dev;
+#endif
 	struct onoff_client clk_cli;
 	struct k_mem_slab *mem_slab;
 	uint32_t block_size;
@@ -61,6 +70,35 @@ static void stop_pdm(struct dmic_nrfx_pdm_drv_data *drv_data)
 	nrfx_pdm_stop(drv_data->pdm);
 }
 
+static int request_clock(struct dmic_nrfx_pdm_drv_data *drv_data)
+{
+	if (!drv_data->request_clock) {
+		return 0;
+	}
+#if CONFIG_CLOCK_CONTROL_NRF
+	return onoff_request(drv_data->clk_mgr, &drv_data->clk_cli);
+#elif CONFIG_CLOCK_CONTROL_NRF2_AUDIOPLL
+	return nrf_clock_control_request(drv_data->audiopll_dev, NULL, &drv_data->clk_cli);
+#else
+	return 0;
+#endif
+}
+
+static int release_clock(struct dmic_nrfx_pdm_drv_data *drv_data)
+{
+	if (!drv_data->request_clock) {
+		return 0;
+	}
+
+#if CONFIG_CLOCK_CONTROL_NRF
+	return onoff_release(drv_data->clk_mgr);
+#elif CONFIG_CLOCK_CONTROL_NRF2_AUDIOPLL
+	return nrf_clock_control_release(drv_data->audiopll_dev, NULL);
+#else
+	return 0;
+#endif
+}
+
 static void event_handler(const struct device *dev, const nrfx_pdm_evt_t *evt)
 {
 	struct dmic_nrfx_pdm_drv_data *drv_data = dev->data;
@@ -119,8 +157,10 @@ static void event_handler(const struct device *dev, const nrfx_pdm_evt_t *evt)
 
 		if (drv_data->active) {
 			drv_data->active = false;
-			if (drv_data->request_clock) {
-				(void)onoff_release(drv_data->clk_mgr);
+			ret = release_clock(drv_data);
+			if (ret < 0) {
+				LOG_ERR("Failed to release clock: %d", ret);
+				return;
 			}
 		}
 	} else if (evt->buffer_released) {
@@ -191,9 +231,11 @@ static bool check_pdm_frequencies(const struct dmic_nrfx_pdm_drv_cfg *drv_cfg,
 {
 	uint32_t req_rate = pdm_cfg->streams[0].pcm_rate;
 	bool better_found = false;
-
+	const uint32_t src_freq =
+		(NRF_PDM_HAS_SELECTABLE_CLOCK && drv_cfg->clk_src == ACLK)
+		? DMIC_NRFX_AUDIO_CLOCK_FREQ
+		: DMIC_NRFX_CLOCK_FREQ;
 #if NRF_PDM_HAS_PRESCALER
-	uint32_t src_freq = 32 * 1000 * 1000UL;
 	uint32_t req_freq = req_rate * ratio;
 	uint32_t prescaler = src_freq / req_freq;
 	uint32_t act_freq = src_freq / prescaler;
@@ -224,24 +266,6 @@ static bool check_pdm_frequencies(const struct dmic_nrfx_pdm_drv_cfg *drv_cfg,
 	}
 #else
 	if (IS_ENABLED(CONFIG_SOC_SERIES_NRF53X) || IS_ENABLED(CONFIG_SOC_SERIES_NRF54HX)) {
-		const uint32_t src_freq =
-			(NRF_PDM_HAS_MCLKCONFIG && drv_cfg->clk_src == ACLK)
-			/* The DMIC_NRFX_PDM_DEVICE() macro contains build
-			 * assertions that make sure that the ACLK clock
-			 * source is only used when it is available and only
-			 * with the "hfclkaudio-frequency" property defined,
-			 * but the default value of 0 here needs to be used
-			 * to prevent compilation errors when the property is
-			 * not defined (this expression will be eventually
-			 * optimized away then).
-			 */
-			/* TODO : PS does not provide correct formula for nRF54H20 PDM_CLK.
-			 * Assume that master clock source frequency is 8 MHz. Remove once
-			 * correct formula is found.
-			 */
-			? DT_PROP_OR(DT_NODELABEL(clock), hfclkaudio_frequency,
-				     0)
-			: DMIC_NRFX_CLOCK_FREQ;
 		uint32_t req_freq = req_rate * ratio;
 		/* As specified in the nRF5340 PS:
 		 *
@@ -461,7 +485,7 @@ static int dmic_nrfx_pdm_configure(const struct device *dev,
 		nrfx_cfg.edge = NRF_PDM_EDGE_LEFTRISING;
 		channel->act_chan_map_lo = alt_map;
 	}
-#if NRF_PDM_HAS_MCLKCONFIG
+#if NRF_PDM_HAS_SELECTABLE_CLOCK
 	nrfx_cfg.mclksrc = drv_cfg->clk_src == ACLK
 			 ? NRF_PDM_MCLKSRC_ACLK
 			 : NRF_PDM_MCLKSRC_PCLK32M;
@@ -508,8 +532,10 @@ static int start_transfer(struct dmic_nrfx_pdm_drv_data *drv_data)
 	LOG_ERR("Failed to start PDM: 0x%08x", err);
 	ret =  -EIO;
 
-	if (drv_data->request_clock) {
-		(void)onoff_release(drv_data->clk_mgr);
+	ret = release_clock(drv_data);
+	if (ret < 0) {
+		LOG_ERR("Failed to release clock: %d", ret);
+		return ret;
 	}
 
 	drv_data->active = false;
@@ -529,7 +555,12 @@ static void clock_started_callback(struct onoff_manager *mgr,
 	 * the actual transfer in such case.
 	 */
 	if (!drv_data->active) {
-		(void)onoff_release(drv_data->clk_mgr);
+		int ret = release_clock(drv_data);
+
+		if (ret < 0) {
+			LOG_ERR("Failed to release clock: %d", ret);
+			return;
+		}
 	} else {
 		(void)start_transfer(drv_data);
 	}
@@ -548,7 +579,7 @@ static int trigger_start(const struct device *dev)
 	if (drv_data->request_clock) {
 		sys_notify_init_callback(&drv_data->clk_cli.notify,
 					 clock_started_callback);
-		ret = onoff_request(drv_data->clk_mgr, &drv_data->clk_cli);
+		ret = request_clock(drv_data);
 		if (ret < 0) {
 			drv_data->active = false;
 
@@ -624,12 +655,11 @@ static int dmic_nrfx_pdm_read(const struct device *dev,
 	return ret;
 }
 
-#if CONFIG_CLOCK_CONTROL_NRF
 static void init_clock_manager(const struct device *dev)
 {
-	struct dmic_nrfx_pdm_drv_data *drv_data = dev->data;
+#if CONFIG_CLOCK_CONTROL_NRF
 	clock_control_subsys_t subsys;
-
+	struct dmic_nrfx_pdm_drv_data *drv_data = dev->data;
 #if NRF_CLOCK_HAS_HFCLKAUDIO
 	const struct dmic_nrfx_pdm_drv_cfg *drv_cfg = dev->config;
 
@@ -643,8 +673,12 @@ static void init_clock_manager(const struct device *dev)
 
 	drv_data->clk_mgr = z_nrf_clock_control_get_onoff(subsys);
 	__ASSERT_NO_MSG(drv_data->clk_mgr != NULL);
-}
+#elif CONFIG_CLOCK_CONTROL_NRF2_AUDIOPLL
+	struct dmic_nrfx_pdm_drv_data *drv_data = dev->data;
+
+	drv_data->audiopll_dev = DEVICE_DT_GET(DT_NODELABEL(audiopll));
 #endif
+}
 
 static const struct _dmic_ops dmic_ops = {
 	.configure = dmic_nrfx_pdm_configure,
@@ -677,8 +711,7 @@ static const struct _dmic_ops dmic_ops = {
 		k_msgq_init(&dmic_nrfx_pdm_data##idx.mem_slab_queue,	     \
 			    (char *)mem_slab_msgs##idx, sizeof(void *),	     \
 			    ARRAY_SIZE(mem_slab_msgs##idx));		     \
-		IF_ENABLED(CONFIG_CLOCK_CONTROL_NRF,			     \
-			   (init_clock_manager(dev);))			     \
+		init_clock_manager(dev);				     \
 		return 0;						     \
 	}								     \
 	static void event_handler##idx(const nrfx_pdm_evt_t *evt)	     \
@@ -695,13 +728,20 @@ static const struct _dmic_ops dmic_ops = {
 		.clk_src = PDM_CLK_SRC(idx),				     \
 		.mem_reg = DMM_DEV_TO_REG(PDM(idx)),			     \
 	};								     \
-	BUILD_ASSERT(PDM_CLK_SRC(idx) != ACLK || NRF_PDM_HAS_MCLKCONFIG,     \
+	BUILD_ASSERT(PDM_CLK_SRC(idx) != ACLK ||			     \
+		     NRF_PDM_HAS_SELECTABLE_CLOCK,			     \
 		"Clock source ACLK is not available.");			     \
 	BUILD_ASSERT(PDM_CLK_SRC(idx) != ACLK ||			     \
 		     DT_NODE_HAS_PROP(DT_NODELABEL(clock),		     \
-				      hfclkaudio_frequency),		     \
+				      hfclkaudio_frequency) ||		     \
+		     DT_NODE_HAS_PROP(DT_NODELABEL(aclk),		     \
+				      clock_frequency) ||		     \
+		     DT_NODE_HAS_PROP(DT_NODELABEL(audiopll),		     \
+				      frequency),			     \
 		"Clock source ACLK requires the hfclkaudio-frequency "	     \
-		"property to be defined in the nordic,nrf-clock node.");     \
+		"property to be defined in the nordic,nrf-clock node "	     \
+		"or clock-frequency property to be defined in aclk node"     \
+		"or frequency property to be defined in audiopll node");     \
 	DEVICE_DT_DEFINE(PDM(idx), pdm_nrfx_init##idx, NULL,		     \
 			 &dmic_nrfx_pdm_data##idx, &dmic_nrfx_pdm_cfg##idx,  \
 			 POST_KERNEL, CONFIG_AUDIO_DMIC_INIT_PRIORITY,	     \

dts/bindings/clock/nordic,nrf-aclk.yaml

@@ -0,0 +1,14 @@
+# Copyright (c) 2025 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+description: Nordic Audio clock node
+
+compatible: "nordic,nrf-aclk"
+
+include: fixed-clock.yaml
+
+properties:
+  clock-frequency:
+    type: int
+    description: |
+      Frequency of the Audio clock in Hz.

dts/common/nordic/nrf54l20.dtsi

@@ -76,6 +76,12 @@
 			#clock-cells = <0>;
 			clock-frequency = <DT_FREQ_M(128)>;
 		};
+
+		aclk: aclk {
+			compatible = "nordic,nrf-aclk";
+			#clock-cells = <0>;
+			clock-frequency = <DT_FREQ_M(24)>;
+		};
 	};
 
 	soc {