diff --git a/src/rp2_common/pico_async_context/async_context_freertos.c b/src/rp2_common/pico_async_context/async_context_freertos.c
index f6b1a5a1a..6bc7c460f 100644
--- a/src/rp2_common/pico_async_context/async_context_freertos.c
+++ b/src/rp2_common/pico_async_context/async_context_freertos.c
@@ -226,7 +226,7 @@ static void handle_sync_func_call(async_context_t *context, async_when_pending_w
     xSemaphoreGive(call->sem);
 }
 
-uint32_t async_context_freertos_execute_sync(async_context_t *self_base, uint32_t (*func)(void *param), void *param) {
+static uint32_t async_context_freertos_execute_sync(async_context_t *self_base, uint32_t (*func)(void *param), void *param) {
     async_context_freertos_t *self = (async_context_freertos_t*)self_base;
     hard_assert(xSemaphoreGetMutexHolder(self->lock_mutex) != xTaskGetCurrentTaskHandle());
     sync_func_call_t call = {0};
diff --git a/src/rp2_common/pico_async_context/async_context_poll.c b/src/rp2_common/pico_async_context/async_context_poll.c
index 47991b40d..c82152a2c 100644
--- a/src/rp2_common/pico_async_context/async_context_poll.c
+++ b/src/rp2_common/pico_async_context/async_context_poll.c
@@ -51,7 +51,7 @@ static void async_context_poll_lock_check(async_context_t *self_base) {
     }
 }
 
-uint32_t async_context_poll_execute_sync(__unused async_context_t *context, uint32_t (*func)(void *param), void *param) {
+static uint32_t async_context_poll_execute_sync(__unused async_context_t *context, uint32_t (*func)(void *param), void *param) {
     return func(param);
 }
 
diff --git a/src/rp2_common/pico_async_context/async_context_threadsafe_background.c b/src/rp2_common/pico_async_context/async_context_threadsafe_background.c
index 16571eba0..dd5efa029 100644
--- a/src/rp2_common/pico_async_context/async_context_threadsafe_background.c
+++ b/src/rp2_common/pico_async_context/async_context_threadsafe_background.c
@@ -135,7 +135,7 @@ static void lock_release(async_context_threadsafe_background_t *self) {
 #endif
 }
 
-uint32_t async_context_threadsafe_background_execute_sync(async_context_t *self_base, uint32_t (*func)(void *param), void *param) {
+static uint32_t async_context_threadsafe_background_execute_sync(async_context_t *self_base, uint32_t (*func)(void *param), void *param) {
     async_context_threadsafe_background_t *self = (async_context_threadsafe_background_t*)self_base;
 #if ASYNC_CONTEXT_THREADSAFE_BACKGROUND_MULTI_CORE
     if (self_base->core_num != get_core_num()) {