diff --git a/drivers/timer/nrf_rtc_timer.c b/drivers/timer/nrf_rtc_timer.c
index 35946154cd9..38b31671e44 100644
--- a/drivers/timer/nrf_rtc_timer.c
+++ b/drivers/timer/nrf_rtc_timer.c
@@ -51,27 +51,27 @@ static uint32_t counter_sub(uint32_t a, uint32_t b)
 	return (a - b) & COUNTER_MAX;
 }
 
-static void set_comparator(uint32_t chan, uint32_t cyc)
+static void set_comparator(int32_t chan, uint32_t cyc)
 {
 	nrf_rtc_cc_set(RTC, chan, cyc & COUNTER_MAX);
 }
 
-static uint32_t get_comparator(uint32_t chan)
+static uint32_t get_comparator(int32_t chan)
 {
 	return nrf_rtc_cc_get(RTC, chan);
 }
 
-static void event_clear(uint32_t chan)
+static void event_clear(int32_t chan)
 {
 	nrf_rtc_event_clear(RTC, RTC_CHANNEL_EVENT_ADDR(chan));
 }
 
-static void event_enable(uint32_t chan)
+static void event_enable(int32_t chan)
 {
 	nrf_rtc_event_enable(RTC, RTC_CHANNEL_INT_MASK(chan));
 }
 
-static void event_disable(uint32_t chan)
+static void event_disable(int32_t chan)
 {
 	nrf_rtc_event_disable(RTC, RTC_CHANNEL_INT_MASK(chan));
 }
@@ -86,13 +86,13 @@ uint32_t z_nrf_rtc_timer_read(void)
 	return nrf_rtc_counter_get(RTC);
 }
 
-uint32_t z_nrf_rtc_timer_compare_evt_address_get(uint32_t chan)
+uint32_t z_nrf_rtc_timer_compare_evt_address_get(int32_t chan)
 {
 	__ASSERT_NO_MSG(chan < CHAN_COUNT);
 	return nrf_rtc_event_address_get(RTC, nrf_rtc_compare_event_get(chan));
 }
 
-bool z_nrf_rtc_timer_compare_int_lock(uint32_t chan)
+bool z_nrf_rtc_timer_compare_int_lock(int32_t chan)
 {
 	__ASSERT_NO_MSG(chan && chan < CHAN_COUNT);
 
@@ -103,7 +103,7 @@ bool z_nrf_rtc_timer_compare_int_lock(uint32_t chan)
 	return prev & BIT(chan);
 }
 
-void z_nrf_rtc_timer_compare_int_unlock(uint32_t chan, bool key)
+void z_nrf_rtc_timer_compare_int_unlock(int32_t chan, bool key)
 {
 	__ASSERT_NO_MSG(chan && chan < CHAN_COUNT);
 
@@ -113,7 +113,7 @@ void z_nrf_rtc_timer_compare_int_unlock(uint32_t chan, bool key)
 	}
 }
 
-uint32_t z_nrf_rtc_timer_compare_read(uint32_t chan)
+uint32_t z_nrf_rtc_timer_compare_read(int32_t chan)
 {
 	__ASSERT_NO_MSG(chan < CHAN_COUNT);
 
@@ -154,7 +154,7 @@ int z_nrf_rtc_timer_get_ticks(k_timeout_t t)
  * less than COUNTER_HALF_SPAN from now. It detects late setting and also
  * handle +1 cycle case.
  */
-static void set_absolute_alarm(uint32_t chan, uint32_t abs_val)
+static void set_absolute_alarm(int32_t chan, uint32_t abs_val)
 {
 	uint32_t now;
 	uint32_t now2;
@@ -203,7 +203,7 @@ static void set_absolute_alarm(uint32_t chan, uint32_t abs_val)
 		 (counter_sub(cc_val, now2 + 2) > COUNTER_HALF_SPAN));
 }
 
-static void compare_set(uint32_t chan, uint32_t cc_value,
+static void compare_set(int32_t chan, uint32_t cc_value,
 			z_nrf_rtc_timer_compare_handler_t handler,
 			void *user_data)
 {
@@ -213,7 +213,7 @@ static void compare_set(uint32_t chan, uint32_t cc_value,
 	set_absolute_alarm(chan, cc_value);
 }
 
-void z_nrf_rtc_timer_compare_set(uint32_t chan, uint32_t cc_value,
+void z_nrf_rtc_timer_compare_set(int32_t chan, uint32_t cc_value,
 			      z_nrf_rtc_timer_compare_handler_t handler,
 			      void *user_data)
 {
@@ -226,7 +226,7 @@ void z_nrf_rtc_timer_compare_set(uint32_t chan, uint32_t cc_value,
 	z_nrf_rtc_timer_compare_int_unlock(chan, key);
 }
 
-static void sys_clock_timeout_handler(uint32_t chan,
+static void sys_clock_timeout_handler(int32_t chan,
 				      uint32_t cc_value,
 				      void *user_data)
 {
@@ -258,7 +258,7 @@ void rtc_nrf_isr(const void *arg)
 {
 	ARG_UNUSED(arg);
 
-	for (uint32_t chan = 0; chan < CHAN_COUNT; chan++) {
+	for (int32_t chan = 0; chan < CHAN_COUNT; chan++) {
 		if (nrf_rtc_int_enable_check(RTC, RTC_CHANNEL_INT_MASK(chan)) &&
 		    nrf_rtc_event_check(RTC, RTC_CHANNEL_EVENT_ADDR(chan))) {
 			uint32_t cc_val;
@@ -277,9 +277,9 @@ void rtc_nrf_isr(const void *arg)
 	}
 }
 
-int z_nrf_rtc_timer_chan_alloc(void)
+int32_t z_nrf_rtc_timer_chan_alloc(void)
 {
-	int chan;
+	int32_t chan;
 	atomic_val_t prev;
 	do {
 		chan = alloc_mask ? 31 - __builtin_clz(alloc_mask) : -1;
@@ -292,7 +292,7 @@ int z_nrf_rtc_timer_chan_alloc(void)
 	return chan;
 }
 
-void z_nrf_rtc_timer_chan_free(uint32_t chan)
+void z_nrf_rtc_timer_chan_free(int32_t chan)
 {
 	__ASSERT_NO_MSG(chan && chan < CHAN_COUNT);
 
@@ -311,7 +311,7 @@ int sys_clock_driver_init(const struct device *dev)
 
 	/* TODO: replace with counter driver to access RTC */
 	nrf_rtc_prescaler_set(RTC, 0);
-	for (uint32_t chan = 0; chan < CHAN_COUNT; chan++) {
+	for (int32_t chan = 0; chan < CHAN_COUNT; chan++) {
 		nrf_rtc_int_enable(RTC, RTC_CHANNEL_INT_MASK(chan));
 	}
 
diff --git a/include/drivers/timer/nrf_rtc_timer.h b/include/drivers/timer/nrf_rtc_timer.h
index 321289c4907..f4b502edffc 100644
--- a/include/drivers/timer/nrf_rtc_timer.h
+++ b/include/drivers/timer/nrf_rtc_timer.h
@@ -11,7 +11,7 @@
 extern "C" {
 #endif
 
-typedef void (*z_nrf_rtc_timer_compare_handler_t)(uint32_t id,
+typedef void (*z_nrf_rtc_timer_compare_handler_t)(int32_t id,
 						uint32_t cc_value,
 						void *user_data);
 
@@ -22,13 +22,13 @@ typedef void (*z_nrf_rtc_timer_compare_handler_t)(uint32_t id,
  * @retval Non-negative indicates allocated channel ID.
  * @retval -ENOMEM if channel cannot be allocated.
  */
-int z_nrf_rtc_timer_chan_alloc(void);
+int32_t z_nrf_rtc_timer_chan_alloc(void);
 
 /** @brief Free RTC compare channel.
  *
  * @param chan Previously allocated channel ID.
  */
-void z_nrf_rtc_timer_chan_free(uint32_t chan);
+void z_nrf_rtc_timer_chan_free(int32_t chan);
 
 /** @brief Read current RTC counter value.
  *
@@ -44,7 +44,7 @@ uint32_t z_nrf_rtc_timer_read(void);
  *
  * @return Register address.
  */
-uint32_t z_nrf_rtc_timer_compare_evt_address_get(uint32_t chan);
+uint32_t z_nrf_rtc_timer_compare_evt_address_get(int32_t chan);
 
 /** @brief Safely disable compare event interrupt.
  *
@@ -54,7 +54,7 @@ uint32_t z_nrf_rtc_timer_compare_evt_address_get(uint32_t chan);
  *
  * @return key passed to @ref z_nrf_rtc_timer_compare_int_unlock.
  */
-bool z_nrf_rtc_timer_compare_int_lock(uint32_t chan);
+bool z_nrf_rtc_timer_compare_int_lock(int32_t chan);
 
 /** @brief Safely enable compare event interrupt.
  *
@@ -64,7 +64,7 @@ bool z_nrf_rtc_timer_compare_int_lock(uint32_t chan);
  *
  * @param key Key returned by @ref z_nrf_rtc_timer_compare_int_lock.
  */
-void z_nrf_rtc_timer_compare_int_unlock(uint32_t chan, bool key);
+void z_nrf_rtc_timer_compare_int_unlock(int32_t chan, bool key);
 
 /** @brief Read compare register value.
  *
@@ -72,7 +72,7 @@ void z_nrf_rtc_timer_compare_int_unlock(uint32_t chan, bool key);
  *
  * @return Value set in the compare register.
  */
-uint32_t z_nrf_rtc_timer_compare_read(uint32_t chan);
+uint32_t z_nrf_rtc_timer_compare_read(int32_t chan);
 
 /** @brief  Try to set compare channel to given value.
  *
@@ -95,7 +95,7 @@ uint32_t z_nrf_rtc_timer_compare_read(uint32_t chan);
  *
  * @param user_data Data passed to the handler.
  */
-void z_nrf_rtc_timer_compare_set(uint32_t chan, uint32_t cc_value,
+void z_nrf_rtc_timer_compare_set(int32_t chan, uint32_t cc_value,
 			       z_nrf_rtc_timer_compare_handler_t handler,
 			       void *user_data);
 
diff --git a/modules/hal_nordic/nrf_802154/sl_opensource/platform/nrf_802154_lp_timer_zephyr.c b/modules/hal_nordic/nrf_802154/sl_opensource/platform/nrf_802154_lp_timer_zephyr.c
index 2d862d63bfb..11d430a1195 100644
--- a/modules/hal_nordic/nrf_802154/sl_opensource/platform/nrf_802154_lp_timer_zephyr.c
+++ b/modules/hal_nordic/nrf_802154/sl_opensource/platform/nrf_802154_lp_timer_zephyr.c
@@ -17,10 +17,10 @@
 
 static volatile bool m_clock_ready;
 static bool m_is_running;
-static uint32_t m_rtc_channel;
+static int32_t m_rtc_channel;
 static bool m_in_critical_section;
 
-void rtc_irq_handler(uint32_t id, uint32_t cc_value, void *user_data)
+void rtc_irq_handler(int32_t id, uint32_t cc_value, void *user_data)
 {
 	(void)cc_value;
 	(void)user_data;
@@ -81,11 +81,8 @@ void nrf_802154_lp_timer_init(void)
 		/* Intentionally empty */
 	}
 
-	int32_t chan = z_nrf_rtc_timer_chan_alloc();
-
-	if (chan >= 0) {
-		m_rtc_channel = (uint32_t)chan;
-	} else   {
+	m_rtc_channel = z_nrf_rtc_timer_chan_alloc();
+	if (m_rtc_channel < 0) {
 		assert(false);
 		return;
 	}