nfc: tnep tag separate signalling layer for Bare Metal

include/nfc/tnep/tag.h

@@ -17,9 +17,6 @@
 #include <nfc/tnep/base.h>
 #include <zephyr/kernel.h>
 
-/** NFC TNEP library event count. */
-#define NFC_TNEP_EVENTS_NUMBER 2
-
 /** Maximum Service Waiting Time. */
 #define NFC_TNEP_TAG_MAX_WAIT_TIME 63
 
@@ -188,8 +185,8 @@ int nfc_tnep_tag_tx_msg_buffer_register(uint8_t *tx_buff,
 /**
  * @brief Start communication using TNEP.
  *
- * @param[out] events TNEP Tag Events.
- * @param[in] event_cnt Event count. This library needs 2 events.
+ * @note This function must be called after @ref nfc_tnep_tag_signalling_init.
+ *
  * @param[in] payload_set Function for setting NDEF data for NFC TNEP
  *                        Tag Device. This library use it internally
  *                        to set raw NDEF message to the Tag NDEF file.
@@ -199,8 +196,7 @@ int nfc_tnep_tag_tx_msg_buffer_register(uint8_t *tx_buff,
  * @retval 0 If the operation was successful.
  *           Otherwise, a (negative) error code is returned.
  */
-int nfc_tnep_tag_init(struct k_poll_event *events, uint8_t event_cnt,
-		      nfc_payload_set_t payload_set);
+int nfc_tnep_tag_init(nfc_payload_set_t payload_set);
 
 /**
  * @brief Create the Initial TNEP NDEF message.

include/nfc/tnep/tag_signalling.h

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2026 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#ifndef NFC_TNEP_TAG_SIGNALLING_H_
+#define NFC_TNEP_TAG_SIGNALLING_H_
+
+#include <stdbool.h>
+
+enum tnep_event {
+	TNEP_EVENT_DUMMY,
+	TNEP_EVENT_MSG_RX_NEW,
+	TNEP_EVENT_TAG_SELECTED,
+};
+
+/** @brief Raises a receive event.
+ *
+ * @param event Event to be raised.
+ */
+void nfc_tnep_tag_signalling_rx_event_raise(enum tnep_event event);
+
+/** @brief Raises a transmit event.
+ *
+ * @param event Event to be raised.
+ */
+void nfc_tnep_tag_signalling_tx_event_raise(enum tnep_event event);
+
+/** @brief Checks and clears receive event.
+ *
+ * @param event Pointer to store the raised event.
+ *              The value is valid only if the function returns @c true.
+ *
+ * @retval true  if a receive event was raised.
+ * @retval false if no receive event was raised.
+ */
+bool nfc_tnep_tag_signalling_rx_event_check_and_clear(enum tnep_event *event);
+
+/** @brief Checks and clears transmit event.
+ *
+ * @param event Pointer to store the raised event.
+ *              The value is valid only if the function returns @c true.
+ *
+ * @retval true  if a transmit event was raised.
+ * @retval false if no transmit event was raised.
+ */
+bool nfc_tnep_tag_signalling_tx_event_check_and_clear(enum tnep_event *event);
+
+#endif /* NFC_TNEP_TAG_SIGNALLING_H_ */

include/nfc/tnep/tag_signalling_zephyr.h

@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 2026 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#ifndef NFC_TNEP_TAG_SIGNALLING_ZEPHYR_H_
+#define NFC_TNEP_TAG_SIGNALLING_ZEPHYR_H_
+
+#include <stdint.h>
+#include <zephyr/kernel.h>
+
+/** NFC TNEP library event count. */
+#define NFC_TNEP_EVENTS_NUMBER 2
+
+/** @brief Initializes TNEP signalling using Zephyr primitives.
+ *
+ * @param[out] events     Pointer to array of k_poll_event structures.
+ * @param[in]  event_cnt  Number of events in the array.
+ *                        Must be @ref NFC_TNEP_EVENTS_NUMBER.
+ *
+ * @retval 0 If the operation was successful.
+ *           Otherwise, an (negative) error code is returned.
+ */
+int nfc_tnep_tag_signalling_init(struct k_poll_event *events, uint8_t event_cnt);
+
+#endif /* NFC_TNEP_TAG_SIGNALLING_ZEPHYR_H_ */

samples/bluetooth/peripheral_nfc_pairing/src/main.c

@@ -23,6 +23,7 @@
 #include <nfc/ndef/le_oob_rec_parser.h>
 
 #include <nfc/tnep/tag.h>
+#include <nfc/tnep/tag_signalling_zephyr.h>
 #include <nfc/tnep/ch.h>
 
 #include <zephyr/settings/settings.h>
@@ -656,8 +657,13 @@ static void nfc_init(void)
 		return;
 	}
 
-	err = nfc_tnep_tag_init(events, NFC_TNEP_EVENTS_NUMBER,
-				nfc_t4t_ndef_rwpayload_set);
+	err = nfc_tnep_tag_signalling_init(events, NFC_TNEP_EVENTS_NUMBER);
+	if (err) {
+		printk("Cannot initialize tnep signalling, err: %d\n", err);
+		return;
+	}
+
+	err = nfc_tnep_tag_init(nfc_t4t_ndef_rwpayload_set);
 	if (err) {
 		printk("Cannot initialize TNEP protocol, err: %d\n", err);
 		return;

samples/nfc/tnep_tag/src/main.c

@@ -12,6 +12,7 @@
 
 #include <nfc_t4t_lib.h>
 #include <nfc/tnep/tag.h>
+#include <nfc/tnep/tag_signalling_zephyr.h>
 #include <nfc/t4t/ndef_file.h>
 #include <nfc/ndef/msg.h>
 #include <nfc/ndef/text_rec.h>
@@ -209,8 +210,13 @@ int main(void)
 		return 0;
 	}
 
-	err = nfc_tnep_tag_init(events, ARRAY_SIZE(events),
-				nfc_t4t_ndef_rwpayload_set);
+	err = nfc_tnep_tag_signalling_init(events, ARRAY_SIZE(events));
+	if (err) {
+		printk("Cannot initialize tnep signalling, err: %d\n", err);
+		return 0;
+	}
+
+	err = nfc_tnep_tag_init(nfc_t4t_ndef_rwpayload_set);
 	if (err) {
 		printk("Cannot initialize TNEP protocol, err: %d\n", err);
 		return 0;

subsys/nfc/tnep/CMakeLists.txt

@@ -6,6 +6,7 @@
 
 zephyr_library()
 zephyr_library_sources_ifdef(CONFIG_NFC_TNEP_TAG tag.c)
+zephyr_library_sources_ifdef(CONFIG_NFC_TNEP_TAG_SIGNALLING_ZEPHYR tag_signalling_zephyr.c)
 zephyr_library_sources_ifdef(CONFIG_NFC_TNEP_POLLER poller.c)
 
 add_subdirectory_ifdef(CONFIG_NFC_TNEP_CH ch)

subsys/nfc/tnep/Kconfig

@@ -28,6 +28,15 @@ config NFC_TNEP_RX_MAX_RECORD_SIZE
 	help
 	  Set the maximum size of received NDEF Record
 
+choice NFC_TNEP_TAG_SIGNALLING
+	prompt "NFC TNEP Tag signalling method"
+
+config NFC_TNEP_TAG_SIGNALLING_ZEPHYR
+	bool "NFC TNEP Tag signalling using Zephyr primitives"
+	select POLL
+
+endchoice
+
 module = NFC_TNEP_TAG
 module-str = TNEP_TAG
 source "$(ZEPHYR_BASE)/subsys/logging/Kconfig.template.log_config"

subsys/nfc/tnep/tag.c

@@ -7,22 +7,14 @@
 #include <stdbool.h>
 #include <zephyr/kernel.h>
 #include <nfc/tnep/tag.h>
+#include <nfc/tnep/tag_signalling.h>
 #include <nfc/ndef/msg.h>
 #include <nfc/t4t/ndef_file.h>
 #include <nfc/ndef/msg_parser.h>
 #include <zephyr/logging/log.h>
 
 LOG_MODULE_REGISTER(nfc_tnep_tag, CONFIG_NFC_TNEP_TAG_LOG_LEVEL);
 
-#define TNEP_EVENT_RX_IDX 0
-#define TNEP_EVENT_TX_IDX 1
-
-enum tnep_event {
-	TNEP_EVENT_DUMMY,
-	TNEP_EVENT_MSG_RX_NEW,
-	TNEP_EVENT_TAG_SELECTED,
-};
-
 enum tnep_state_name {
 	TNEP_STATE_DISABLED,
 	TNEP_STATE_SERVICE_READY,
@@ -53,12 +45,6 @@ struct tnep_rx_buffer {
 	size_t len;
 };
 
-struct tnep_control {
-	struct k_poll_event *events;
-	struct k_poll_signal msg_rx;
-	struct k_poll_signal msg_tx;
-};
-
 struct tnep_tag {
 	struct nfc_ndef_msg_desc *msg;
 	struct tnep_buffer tx;
@@ -72,7 +58,6 @@ struct tnep_tag {
 	uint8_t *current_buff;
 };
 
-static struct tnep_control tnep_ctrl;
 static struct tnep_tag tnep;
 
 struct tnep_state {
@@ -501,11 +486,10 @@ void nfc_tnep_tag_rx_msg_indicate(const uint8_t *rx_buffer, size_t len)
 	tnep.rx.len = len;
 	tnep.rx.data = rx_buffer;
 
-	k_poll_signal_raise(&tnep_ctrl.msg_rx, TNEP_EVENT_MSG_RX_NEW);
+	nfc_tnep_tag_signalling_rx_event_raise(TNEP_EVENT_MSG_RX_NEW);
 }
 
-int nfc_tnep_tag_init(struct k_poll_event *events, uint8_t event_cnt,
-		      nfc_payload_set_t payload_set)
+int nfc_tnep_tag_init(nfc_payload_set_t payload_set)
 {
 	extern struct nfc_tnep_tag_service
 			_nfc_tnep_tag_service_list_start[];
@@ -514,21 +498,11 @@ int nfc_tnep_tag_init(struct k_poll_event *events, uint8_t event_cnt,
 
 	LOG_DBG("TNEP initialization");
 
-	if (!events) {
-		return -EINVAL;
-	}
-
 	if (!payload_set) {
 		LOG_ERR("No function for NFC payload set provided");
 		return -EINVAL;
 	}
 
-	if (event_cnt != NFC_TNEP_EVENTS_NUMBER) {
-		LOG_ERR("Invalid k_pool events count. Got %d events, required %d",
-			event_cnt, NFC_TNEP_EVENTS_NUMBER);
-		return -EINVAL;
-	}
-
 	if (!atomic_cas(&current_state, TNEP_STATE_DISABLED,
 			TNEP_STATE_DISABLED)) {
 		LOG_ERR("TNEP already running");
@@ -541,25 +515,11 @@ int nfc_tnep_tag_init(struct k_poll_event *events, uint8_t event_cnt,
 		return -EIO;
 	}
 
-	tnep_ctrl.events = events;
 	tnep.current_buff = tnep.tx.data;
 	tnep.data_set = payload_set;
 	tnep.svc_cnt = _nfc_tnep_tag_service_list_end -
 		       _nfc_tnep_tag_service_list_start;
 
-	LOG_DBG("k_pool signals initialization");
-
-	k_poll_signal_init(&tnep_ctrl.msg_rx);
-	k_poll_signal_init(&tnep_ctrl.msg_tx);
-
-	k_poll_event_init(&tnep_ctrl.events[TNEP_EVENT_RX_IDX],
-			  K_POLL_TYPE_SIGNAL, K_POLL_MODE_NOTIFY_ONLY,
-			  &tnep_ctrl.msg_rx);
-
-	k_poll_event_init(&tnep_ctrl.events[TNEP_EVENT_TX_IDX],
-			  K_POLL_TYPE_SIGNAL, K_POLL_MODE_NOTIFY_ONLY,
-			  &tnep_ctrl.msg_tx);
-
 	return 0;
 }
 
@@ -635,19 +595,16 @@ int nfc_tnep_initial_msg_encode(struct nfc_ndef_msg_desc *msg,
 
 void nfc_tnep_tag_process(void)
 {
-	/* Check for signals */
-	for (size_t i = 0; i < NFC_TNEP_EVENTS_NUMBER; i++) {
-		if (tnep_ctrl.events[i].state == K_POLL_STATE_SIGNALED) {
-			enum tnep_event event;
-
-			event = tnep_ctrl.events[i].signal->result;
+	enum tnep_event event = TNEP_EVENT_DUMMY;
 
-			k_poll_signal_reset(tnep_ctrl.events[i].signal);
-			tnep_ctrl.events[i].state = K_POLL_STATE_NOT_READY;
+	if (nfc_tnep_tag_signalling_rx_event_check_and_clear(&event)) {
+		/* Run TNEP State Machine - prepare response */
+		tnep_state_machine[atomic_get(&current_state)].process(event);
+	}
 
-			/* Run TNEP State Machine - prepare response */
-			tnep_state_machine[atomic_get(&current_state)].process(event);
-		}
+	if (nfc_tnep_tag_signalling_tx_event_check_and_clear(&event)) {
+		/* Run TNEP State Machine - prepare response */
+		tnep_state_machine[atomic_get(&current_state)].process(event);
 	}
 }
 
@@ -707,7 +664,7 @@ int nfc_tnep_tag_tx_msg_no_app_data(void)
 
 void nfc_tnep_tag_on_selected(void)
 {
-	k_poll_signal_raise(&tnep_ctrl.msg_tx, TNEP_EVENT_TAG_SELECTED);
+	nfc_tnep_tag_signalling_tx_event_raise(TNEP_EVENT_TAG_SELECTED);
 }
 
 size_t nfc_tnep_tag_svc_count_get(void)