Move random utils to another trait.

embassy-stm32/src/rng.rs

@@ -126,7 +126,9 @@ impl<T: Instance> traits::rng::Rng for Random<T> {
             Ok(())
         }
     }
+}
 
+impl<T: Instance> traits::rng::Random for Random<T> {
     #[rustfmt::skip]
     type NextFuture<'a> where Self: 'a = impl Future<Output=Result<u32, Self::Error>> + 'a;
 

embassy-traits/src/rng.rs

@@ -5,7 +5,7 @@ pub trait Rng {
     type Error;
 
     #[rustfmt::skip]
-    type RngFuture<'a>: Future<Output = Result<(), Self::Error>> + 'a
+    type RngFuture<'a>: Future<Output = Result<(), Self::Error> > + 'a
     where
     Self: 'a;
 
@@ -15,9 +15,11 @@ pub trait Rng {
     /// filling the buffer. Upon completion, the buffer will be completely
     /// filled or an error will have been reported.
     fn fill_bytes<'a>(&'a mut self, dest: &'a mut [u8]) -> Self::RngFuture<'a>;
+}
 
+pub trait Random: Rng {
     #[rustfmt::skip]
-    type NextFuture<'a>: Future<Output = Result<u32, Self::Error>> + 'a
+    type NextFuture<'a>: Future<Output = Result<u32, <Self as Rng>::Error>> + 'a
     where
         Self: 'a;
 

examples/stm32h7/src/bin/rng.rs

@@ -13,7 +13,7 @@ use embassy_stm32::Peripherals;
 use embedded_hal::digital::v2::OutputPin;
 use example_common::*;
 use embassy_stm32::rng::Random;
-use embassy::traits::rng::Rng;
+use embassy::traits::rng::Random as _;
 
 #[embassy::main]
 async fn main(_spawner: Spawner, p: Peripherals) {