stm32/dma: add ChannelAndRequest helper.

2 files changed, 63 insertions, 0 deletions

diff --git a/embassy-stm32/src/dma/mod.rs b/embassy-stm32/src/dma/mod.rs
index 7e3681469..8766d0a60 100644
--- a/embassy-stm32/src/dma/mod.rs
+++ b/embassy-stm32/src/dma/mod.rs
@@ -16,6 +16,9 @@ mod dmamux;
 #[cfg(dmamux)]
 pub use dmamux::*;
 
+mod util;
+pub(crate) use util::*;
+
 pub(crate) mod ringbuffer;
 pub mod word;
 
diff --git a/embassy-stm32/src/dma/util.rs b/embassy-stm32/src/dma/util.rs
new file mode 100644
index 000000000..962ea2501
--- /dev/null
+++ b/embassy-stm32/src/dma/util.rs
@@ -0,0 +1,60 @@
+use embassy_hal_internal::PeripheralRef;
+
+use super::word::Word;
+use super::{AnyChannel, Request, Transfer, TransferOptions};
+
+/// Convenience wrapper, contains a channel and a request number.
+///
+/// Commonly used in peripheral drivers that own DMA channels.
+pub(crate) struct ChannelAndRequest<'d> {
+    pub channel: PeripheralRef<'d, AnyChannel>,
+    pub request: Request,
+}
+
+impl<'d> ChannelAndRequest<'d> {
+    pub unsafe fn read<'a, W: Word>(
+        &'a mut self,
+        peri_addr: *mut W,
+        buf: &'a mut [W],
+        options: TransferOptions,
+    ) -> Transfer<'a> {
+        Transfer::new_read(&mut self.channel, self.request, peri_addr, buf, options)
+    }
+
+    pub unsafe fn read_raw<'a, W: Word>(
+        &'a mut self,
+        peri_addr: *mut W,
+        buf: *mut [W],
+        options: TransferOptions,
+    ) -> Transfer<'a> {
+        Transfer::new_read_raw(&mut self.channel, self.request, peri_addr, buf, options)
+    }
+
+    pub unsafe fn write<'a, W: Word>(
+        &'a mut self,
+        buf: &'a [W],
+        peri_addr: *mut W,
+        options: TransferOptions,
+    ) -> Transfer<'a> {
+        Transfer::new_write(&mut self.channel, self.request, buf, peri_addr, options)
+    }
+
+    pub unsafe fn write_raw<'a, W: Word>(
+        &'a mut self,
+        buf: *const [W],
+        peri_addr: *mut W,
+        options: TransferOptions,
+    ) -> Transfer<'a> {
+        Transfer::new_write_raw(&mut self.channel, self.request, buf, peri_addr, options)
+    }
+
+    pub unsafe fn write_repeated<'a, W: Word>(
+        &'a mut self,
+        repeated: &'a W,
+        count: usize,
+        peri_addr: *mut W,
+        options: TransferOptions,
+    ) -> Transfer<'a> {
+        Transfer::new_write_repeated(&mut self.channel, self.request, repeated, count, peri_addr, options)
+    }
+}