From 014583aaa5dd10d4580aa24ec9b9f2ddb963559a Mon Sep 17 00:00:00 2001
From: Dario Nieuwenhuis <dirbaio@dirbaio.net>
Date: Mon, 14 Oct 2024 12:43:59 +0200
Subject: [PATCH] tests/stm32: add uart async and blocking flush test.

---
 tests/stm32/src/bin/usart.rs     |  7 +++++++
 tests/stm32/src/bin/usart_dma.rs | 17 +++++++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/tests/stm32/src/bin/usart.rs b/tests/stm32/src/bin/usart.rs
index 53da30fff..2f601ad0e 100644
--- a/tests/stm32/src/bin/usart.rs
+++ b/tests/stm32/src/bin/usart.rs
@@ -33,6 +33,13 @@ async fn main(_spawner: Spawner) {
         let mut buf = [0; 2];
         usart.blocking_read(&mut buf).unwrap();
         assert_eq!(buf, data);
+
+        // Test flush doesn't hang.
+        usart.blocking_write(&data).unwrap();
+        usart.blocking_flush().unwrap();
+
+        // Test flush doesn't hang if there's nothing to flush
+        usart.blocking_flush().unwrap();
     }
 
     // Test error handling with with an overflow error
diff --git a/tests/stm32/src/bin/usart_dma.rs b/tests/stm32/src/bin/usart_dma.rs
index 266b81809..a34498376 100644
--- a/tests/stm32/src/bin/usart_dma.rs
+++ b/tests/stm32/src/bin/usart_dma.rs
@@ -51,6 +51,23 @@ async fn main(_spawner: Spawner) {
         assert_eq!(tx_buf, rx_buf);
     }
 
+    // Test flush doesn't hang. Check multiple combinations of async+blocking.
+    tx.write(&tx_buf).await.unwrap();
+    tx.flush().await.unwrap();
+    tx.flush().await.unwrap();
+
+    tx.write(&tx_buf).await.unwrap();
+    tx.blocking_flush().unwrap();
+    tx.flush().await.unwrap();
+
+    tx.blocking_write(&tx_buf).unwrap();
+    tx.blocking_flush().unwrap();
+    tx.flush().await.unwrap();
+
+    tx.blocking_write(&tx_buf).unwrap();
+    tx.flush().await.unwrap();
+    tx.blocking_flush().unwrap();
+
     info!("Test OK");
     cortex_m::asm::bkpt();
 }