From 5b588a4e07178388f3fcb8b77527f0219717ff10 Mon Sep 17 00:00:00 2001
From: Robin Mueller <robin.mueller.m@pm.me>
Date: Wed, 10 Dec 2025 12:20:54 +0100
Subject: [PATCH] improve async TX API for UART

---
 .../examples/embassy/src/bin/async-uart-tx.rs |  5 ++--
 .../examples/embassy/src/bin/async-uart-tx.rs |  5 ++--
 vorago-shared-hal/src/uart/tx_asynch.rs       | 24 +++++++++++++++++--
 3 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/va108xx/examples/embassy/src/bin/async-uart-tx.rs b/va108xx/examples/embassy/src/bin/async-uart-tx.rs
index 4b70584..7c28f8a 100644
--- a/va108xx/examples/embassy/src/bin/async-uart-tx.rs
+++ b/va108xx/examples/embassy/src/bin/async-uart-tx.rs
@@ -15,7 +15,6 @@ use embassy_example as _;
 
 use embassy_executor::Spawner;
 use embassy_time::{Duration, Instant, Ticker};
-use embedded_io_async::Write;
 use va108xx_hal::{
     gpio::{Output, PinState},
     pac::{self, interrupt},
@@ -70,8 +69,8 @@ async fn main(_spawner: Spawner) {
         led0.toggle();
         led1.toggle();
         led2.toggle();
-        let _written = async_tx
-            .write(STR_LIST[idx].as_bytes())
+        async_tx
+            .write_all(STR_LIST[idx].as_bytes())
             .await
             .expect("writing failed");
         idx += 1;
diff --git a/va416xx/examples/embassy/src/bin/async-uart-tx.rs b/va416xx/examples/embassy/src/bin/async-uart-tx.rs
index 124ee7c..075ca99 100644
--- a/va416xx/examples/embassy/src/bin/async-uart-tx.rs
+++ b/va416xx/examples/embassy/src/bin/async-uart-tx.rs
@@ -19,7 +19,6 @@ use defmt_rtt as _;
 use embassy_example::EXTCLK_FREQ;
 use embassy_executor::Spawner;
 use embassy_time::{Duration, Instant, Ticker};
-use embedded_io_async::Write;
 use va416xx_hal::{
     clock::ClockConfigurator,
     gpio::{Output, PinState},
@@ -69,8 +68,8 @@ async fn main(_spawner: Spawner) {
     loop {
         defmt::println!("Current time: {}", Instant::now().as_secs());
         led.toggle();
-        let _written = async_tx
-            .write(STR_LIST[idx].as_bytes())
+        async_tx
+            .write_all(STR_LIST[idx].as_bytes())
             .await
             .expect("writing failed");
         idx += 1;
diff --git a/vorago-shared-hal/src/uart/tx_asynch.rs b/vorago-shared-hal/src/uart/tx_asynch.rs
index 2cde8d2..4725779 100644
--- a/vorago-shared-hal/src/uart/tx_asynch.rs
+++ b/vorago-shared-hal/src/uart/tx_asynch.rs
@@ -177,6 +177,27 @@ impl TxAsync {
         Self(tx)
     }
 
+    /// Write a buffer asynchronously.
+    ///
+    /// This implementation is not side effect free, and a started future might have already
+    /// written part of the passed buffer.
+    pub async fn write(&mut self, buf: &[u8]) -> Result<usize, TxOverrunError> {
+        let fut = unsafe { TxFuture::new(&mut self.0, buf) };
+        fut.await
+    }
+
+    /// Write an entire buffer into this writer.
+    ///
+    /// This function calls `write()` in a loop until exactly `buf.len()` bytes have
+    /// been written, waiting if needed.
+    ///
+    /// This function is not side-effect-free on cancel (AKA "cancel-safe"), i.e. if you cancel (drop) a returned
+    /// future that hasn't completed yet, some bytes might have already been written.
+    pub async fn write_all(&mut self, buf: &[u8]) -> Result<(), TxOverrunError> {
+        let fut = <Self as embedded_io_async::Write>::write_all(self, buf);
+        fut.await
+    }
+
     pub fn release(self) -> Tx {
         self.0
     }
@@ -203,8 +224,7 @@ impl Write for TxAsync {
     /// This implementation is not side effect free, and a started future might have already
     /// written part of the passed buffer.
     async fn write(&mut self, buf: &[u8]) -> Result<usize, Self::Error> {
-        let fut = unsafe { TxFuture::new(&mut self.0, buf) };
-        fut.await
+        self.write(buf).await
     }
 
     async fn flush(&mut self) -> Result<(), Self::Error> {