diff --git a/components/driver/include/driver/sdio_slave.h b/components/driver/include/driver/sdio_slave.h
index 66b3bc5e2..a54b824c9 100644
--- a/components/driver/include/driver/sdio_slave.h
+++ b/components/driver/include/driver/sdio_slave.h
@@ -197,12 +197,12 @@ uint8_t* sdio_slave_recv_get_buf( sdio_slave_buf_handle_t handle, size_t *len_o)
 esp_err_t sdio_slave_send_queue(uint8_t* addr, size_t len, void* arg, TickType_t wait);
 
 /** Return the ownership of a finished transaction.
- * @param arg_o Argument of the finished transaction.
+ * @param out_arg Argument of the finished transaction. Set to NULL if unused.
  * @param wait Time to wait if there's no finished sending transaction.
  *
  * @return ESP_ERR_TIMEOUT if no transaction finished, or ESP_OK if succeed.
  */
-esp_err_t sdio_slave_send_get_finished(void** arg_o, TickType_t wait);
+esp_err_t sdio_slave_send_get_finished(void** out_arg, TickType_t wait);
 
 /** Start a new sending transfer, and wait for it (blocked) to be finished.
  *
diff --git a/components/driver/sdio_slave.c b/components/driver/sdio_slave.c
index c58c74bd2..5dd870937 100644
--- a/components/driver/sdio_slave.c
+++ b/components/driver/sdio_slave.c
@@ -952,9 +952,11 @@ esp_err_t sdio_slave_send_queue(uint8_t* addr, size_t len, void* arg, TickType_t
     return ESP_OK;
 }
 
-esp_err_t sdio_slave_send_get_finished(void** arg, TickType_t wait)
+esp_err_t sdio_slave_send_get_finished(void** out_arg, TickType_t wait)
 {
-    portBASE_TYPE err = xQueueReceive( context.ret_queue, arg, wait );
+    void* arg = NULL;
+    portBASE_TYPE err = xQueueReceive(context.ret_queue, &arg, wait);
+    if (out_arg) *out_arg = arg;
     if ( err != pdTRUE ) return ESP_ERR_TIMEOUT;
     return ESP_OK;
 }