From 54ada5bae113dbff1f5b76fac2676734f6ddd8eb Mon Sep 17 00:00:00 2001
From: Bob McWhirter <bmcwhirt@redhat.com>
Date: Wed, 30 Jun 2021 14:58:28 -0400
Subject: [PATCH] Stub in the DMA bits that aren't yet there.

---
 embassy-stm32/src/dma/mod.rs      |  2 ++
 embassy-stm32/src/lib.rs          |  2 +-
 embassy-stm32/src/usart/v3.rs     |  3 ++-
 examples/stm32l4/src/bin/usart.rs | 10 +++++++++-
 4 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/embassy-stm32/src/dma/mod.rs b/embassy-stm32/src/dma/mod.rs
index 371741ff..466cfa03 100644
--- a/embassy-stm32/src/dma/mod.rs
+++ b/embassy-stm32/src/dma/mod.rs
@@ -1,9 +1,11 @@
 #![macro_use]
 
+#[cfg(dma)]
 #[cfg_attr(dma_v1, path = "v1.rs")]
 #[cfg_attr(dma_v2, path = "v2.rs")]
 mod _version;
 
+#[cfg(dma)]
 #[allow(unused)]
 pub use _version::*;
 
diff --git a/embassy-stm32/src/lib.rs b/embassy-stm32/src/lib.rs
index 9ba7bbe4..76a6ecd8 100644
--- a/embassy-stm32/src/lib.rs
+++ b/embassy-stm32/src/lib.rs
@@ -26,7 +26,7 @@ pub mod adc;
 pub mod clock;
 #[cfg(dac)]
 pub mod dac;
-#[cfg(dma)]
+#[cfg(any(dma, dmamux))]
 pub mod dma;
 #[cfg(all(eth, feature = "net"))]
 pub mod eth;
diff --git a/embassy-stm32/src/usart/v3.rs b/embassy-stm32/src/usart/v3.rs
index 32850c9c..c45af004 100644
--- a/embassy-stm32/src/usart/v3.rs
+++ b/embassy-stm32/src/usart/v3.rs
@@ -21,7 +21,8 @@ impl<'d, T: Instance> Uart<'d, T> {
     ) -> Self {
         unborrow!(inner, rx, tx);
 
-        T::enable();
+        // Uncomment once we find all of the H7's UART clocks.
+        //T::enable();
         let pclk_freq = T::frequency();
 
         // TODO: better calculation, including error checking and OVER8 if possible.
diff --git a/examples/stm32l4/src/bin/usart.rs b/examples/stm32l4/src/bin/usart.rs
index 6b2b1381..5b6d9eaa 100644
--- a/examples/stm32l4/src/bin/usart.rs
+++ b/examples/stm32l4/src/bin/usart.rs
@@ -58,7 +58,10 @@ fn main() -> ! {
         w.dbg_stop().set_bit()
     });
 
-    pp.RCC.ahb1enr.modify(|_, w| w.dma1en().set_bit());
+    pp.RCC.ahb1enr.modify(|_, w| {
+        w.dma1en().set_bit();
+        w
+    });
 
     pp.RCC.ahb2enr.modify(|_, w| {
         w.gpioaen().set_bit();
@@ -70,6 +73,11 @@ fn main() -> ! {
         w
     });
 
+    pp.RCC.apb1enr1.modify(|_, w| {
+        w.uart4en().set_bit();
+        w
+    });
+
     pp.RCC.apb2enr.modify(|_, w| {
         w.syscfgen().set_bit();
         w