clean code

dma_gpio2/src/bin/main.rs

@@ -25,25 +25,6 @@ pub const TIM6_UP_REQ: Request = 4; // Table 137: tim6_upd_dma, strana 687 STM32
 
 static TX_RING: StaticCell<[u32; TX_RING_BYTES]> = StaticCell::new();
 
-use core::future::poll_fn;
-use core::task::Poll;
-
-async fn wait_for_space<'a, W: embassy_stm32::dma::word::Word>(
-    ring: &mut embassy_stm32::dma::WritableRingBuffer<'a, W>,
-    min_free: usize,
-) {
-    poll_fn(|cx| {
-        let used = ring.len().unwrap_or(0);
-        let cap = ring.capacity();
-        if cap - used > min_free {
-            Poll::Ready(())
-        } else {
-            ring.set_waker(cx.waker());
-            Poll::Pending
-        }
-    }).await
-}
-
 #[embassy_executor::main]
 async fn main(spawner: Spawner) {
     let p = embassy_stm32::init(Default::default());
@@ -87,10 +68,6 @@ async fn main(spawner: Spawner) {
         info!("tick end");
 
         let used = encode_uart_frames(TX_PIN_BIT, b"Hello marshmallow\r\n", &mut frame_buf).await;
-
-        // Wait for DMA to free space, async style
-        wait_for_space(&mut tx_ring, used / 2).await;
-
         if let Err(e) = tx_ring.write_exact(&frame_buf[..used]).await {
             warn!("DMA ring write error: {:?}", e);
         } else {