From 32f7e55f1e8714aa24dffd33b8d5791d0959940d Mon Sep 17 00:00:00 2001
From: Florian Jung <flo@windfis.ch>
Date: Sat, 15 May 2021 00:41:23 +0200
Subject: [PATCH 1/5] Add DMA RX and RX/TX support to SPI

Implements #200
---
 CHANGELOG.md |   4 +-
 src/dma.rs   |  68 +++++++++++++++-
 src/spi.rs   | 216 +++++++++++++++++++++++++++++++++++++++++++++++++--
 3 files changed, 278 insertions(+), 10 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4c38547a..4013636e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,7 +14,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Support for CAN peripherals with the `bxcan` crate
 - Add DAC, UART4, UART5 clock in RCC for the f103 high density line
 - `start_raw` function and `arr`, `bsc` getters for more fine grained
-  control over the timer.
+  control over the timer
+- Added RxTxDma support support to the DMA infrastructure
+- Added DMA receive support for `SPI`
 
 ### Fixed
 - Fix > 2 byte i2c reads
diff --git a/src/dma.rs b/src/dma.rs
index b999fc28..dd9e8579 100644
--- a/src/dma.rs
+++ b/src/dma.rs
@@ -128,7 +128,7 @@ macro_rules! dma {
 
                 use crate::pac::{$DMAX, dma1};
 
-                use crate::dma::{CircBuffer, DmaExt, Error, Event, Half, Transfer, W, RxDma, TxDma, TransferPayload};
+                use crate::dma::{CircBuffer, DmaExt, Error, Event, Half, Transfer, W, RxDma, TxDma, RxTxDma, TransferPayload};
                 use crate::rcc::{AHB, Enable};
 
                 #[allow(clippy::manual_non_exhaustive)]
@@ -371,6 +371,45 @@ macro_rules! dma {
                         }
                     }
 
+                    impl<BUFFER, PAYLOAD, MODE, TXC> Transfer<MODE, BUFFER, RxTxDma<PAYLOAD, $CX, TXC>>
+                    where
+                        RxTxDma<PAYLOAD, $CX, TXC>: TransferPayload,
+                    {
+                        pub fn is_done(&self) -> bool {
+                            !self.payload.rxchannel.in_progress()
+                        }
+
+                        pub fn wait(mut self) -> (BUFFER, RxTxDma<PAYLOAD, $CX, TXC>) {
+                            while !self.is_done() {}
+
+                            atomic::compiler_fence(Ordering::Acquire);
+
+                            self.payload.stop();
+
+                            // we need a read here to make the Acquire fence effective
+                            // we do *not* need this if `dma.stop` does a RMW operation
+                            unsafe { ptr::read_volatile(&0); }
+
+                            // we need a fence here for the same reason we need one in `Transfer.wait`
+                            atomic::compiler_fence(Ordering::Acquire);
+
+                            // `Transfer` needs to have a `Drop` implementation, because we accept
+                            // managed buffers that can free their memory on drop. Because of that
+                            // we can't move out of the `Transfer`'s fields, so we use `ptr::read`
+                            // and `mem::forget`.
+                            //
+                            // NOTE(unsafe) There is no panic branch between getting the resources
+                            // and forgetting `self`.
+                            unsafe {
+                                let buffer = ptr::read(&self.buffer);
+                                let payload = ptr::read(&self.payload);
+                                mem::forget(self);
+                                (buffer, payload)
+                            }
+                        }
+                    }
+
+
                     impl<BUFFER, PAYLOAD> Transfer<W, BUFFER, RxDma<PAYLOAD, $CX>>
                     where
                         RxDma<PAYLOAD, $CX>: TransferPayload,
@@ -387,6 +426,23 @@ macro_rules! dma {
                             &slice[..(capacity - pending)]
                         }
                     }
+
+                    impl<RXBUFFER, TXBUFFER, PAYLOAD, TXC> Transfer<W, (RXBUFFER, TXBUFFER), RxTxDma<PAYLOAD, $CX, TXC>>
+                    where
+                        RxTxDma<PAYLOAD, $CX, TXC>: TransferPayload,
+                    {
+                        pub fn peek<T>(&self) -> &[T]
+                        where
+                            RXBUFFER: AsRef<[T]>,
+                        {
+                            let pending = self.payload.rxchannel.get_ndtr() as usize;
+
+                            let slice = self.buffer.0.as_ref();
+                            let capacity = slice.len();
+
+                            &slice[..(capacity - pending)]
+                        }
+                    }
                 )+
 
                 impl DmaExt for $DMAX {
@@ -532,3 +588,13 @@ where
 {
     fn write(self, buffer: B) -> Transfer<R, B, Self>;
 }
+
+/// Trait for DMA simultaneously reading and writing within one synchronous operation. Panics if both buffers are not of equal length.
+pub trait ReadWriteDma<RXB, TXB, TS>: Transmit
+where
+    RXB: StaticWriteBuffer<Word = TS>,
+    TXB: StaticReadBuffer<Word = TS>,
+    Self: core::marker::Sized + TransferPayload,
+{
+    fn read_write(self, rx_buffer: RXB, tx_buffer: TXB) -> Transfer<W, (RXB, TXB), Self>;
+}
diff --git a/src/spi.rs b/src/spi.rs
index e08cfbba..1f7f042b 100644
--- a/src/spi.rs
+++ b/src/spi.rs
@@ -42,10 +42,10 @@ use crate::pac::SPI3;
 use crate::pac::{SPI1, SPI2};
 
 use crate::afio::MAPR;
-use crate::dma::dma1::{C3, C5};
+use crate::dma::dma1;
 #[cfg(feature = "connectivity")]
-use crate::dma::dma2::C2;
-use crate::dma::{Transfer, TransferPayload, Transmit, TxDma, R};
+use crate::dma::dma2;
+use crate::dma::{Receive, RxDma, RxTxDma, Transfer, TransferPayload, Transmit, TxDma, R, W};
 use crate::gpio::gpioa::{PA5, PA6, PA7};
 use crate::gpio::gpiob::{PB13, PB14, PB15, PB3, PB4, PB5};
 #[cfg(feature = "connectivity")]
@@ -55,7 +55,7 @@ use crate::rcc::{Clocks, Enable, GetBusFreq, Reset, APB1, APB2};
 use crate::time::Hertz;
 
 use core::sync::atomic::{self, Ordering};
-use embedded_dma::StaticReadBuffer;
+use embedded_dma::{StaticReadBuffer, StaticWriteBuffer};
 
 /// SPI error
 #[derive(Debug)]
@@ -551,19 +551,53 @@ pub struct SpiPayload<SPI, REMAP, PINS> {
 }
 
 pub type SpiTxDma<SPI, REMAP, PINS, CHANNEL> = TxDma<SpiPayload<SPI, REMAP, PINS>, CHANNEL>;
+pub type SpiRxDma<SPI, REMAP, PINS, CHANNEL> = RxDma<SpiPayload<SPI, REMAP, PINS>, CHANNEL>;
+pub type SpiRxTxDma<SPI, REMAP, PINS, RXCHANNEL, TXCHANNEL> =
+    RxTxDma<SpiPayload<SPI, REMAP, PINS>, RXCHANNEL, TXCHANNEL>;
 
 macro_rules! spi_dma {
-    ($SPIi:ident, $TCi:ident) => {
+    ($SPIi:ident, $RCi:ty, $TCi:ty) => {
         impl<REMAP, PINS> Transmit for SpiTxDma<$SPIi, REMAP, PINS, $TCi> {
             type TxChannel = $TCi;
             type ReceivedWord = u8;
         }
 
+        impl<REMAP, PINS> Receive for SpiRxDma<$SPIi, REMAP, PINS, $RCi> {
+            type RxChannel = $RCi;
+            type TransmittedWord = u8;
+        }
+
+        impl<REMAP, PINS> Transmit for SpiRxTxDma<$SPIi, REMAP, PINS, $RCi, $TCi> {
+            type TxChannel = $TCi;
+            type ReceivedWord = u8;
+        }
+
+        impl<REMAP, PINS> Receive for SpiRxTxDma<$SPIi, REMAP, PINS, $RCi, $TCi> {
+            type RxChannel = $RCi;
+            type TransmittedWord = u8;
+        }
+
         impl<REMAP, PINS> Spi<$SPIi, REMAP, PINS, u8> {
             pub fn with_tx_dma(self, channel: $TCi) -> SpiTxDma<$SPIi, REMAP, PINS, $TCi> {
                 let payload = SpiPayload { spi: self };
                 SpiTxDma { payload, channel }
             }
+            pub fn with_rx_dma(self, channel: $RCi) -> SpiRxDma<$SPIi, REMAP, PINS, $RCi> {
+                let payload = SpiPayload { spi: self };
+                SpiRxDma { payload, channel }
+            }
+            pub fn with_rx_tx_dma(
+                self,
+                rxchannel: $RCi,
+                txchannel: $TCi,
+            ) -> SpiRxTxDma<$SPIi, REMAP, PINS, $RCi, $TCi> {
+                let payload = SpiPayload { spi: self };
+                SpiRxTxDma {
+                    payload,
+                    rxchannel,
+                    txchannel,
+                }
+            }
         }
 
         impl<REMAP, PINS> TransferPayload for SpiTxDma<$SPIi, REMAP, PINS, $TCi> {
@@ -585,6 +619,89 @@ macro_rules! spi_dma {
             }
         }
 
+        impl<REMAP, PINS> TransferPayload for SpiRxDma<$SPIi, REMAP, PINS, $RCi> {
+            fn start(&mut self) {
+                self.payload
+                    .spi
+                    .spi
+                    .cr2
+                    .modify(|_, w| w.rxdmaen().set_bit());
+                self.channel.start();
+            }
+            fn stop(&mut self) {
+                self.payload
+                    .spi
+                    .spi
+                    .cr2
+                    .modify(|_, w| w.rxdmaen().clear_bit());
+                self.channel.stop();
+            }
+        }
+
+        impl<REMAP, PINS> TransferPayload for SpiRxTxDma<$SPIi, REMAP, PINS, $RCi, $TCi> {
+            fn start(&mut self) {
+                self.payload
+                    .spi
+                    .spi
+                    .cr2
+                    .modify(|_, w| w.rxdmaen().set_bit().txdmaen().set_bit());
+                self.rxchannel.start();
+                self.txchannel.start();
+            }
+            fn stop(&mut self) {
+                self.payload
+                    .spi
+                    .spi
+                    .cr2
+                    .modify(|_, w| w.txdmaen().clear_bit().rxdmaen().clear_bit());
+                self.txchannel.stop();
+                self.rxchannel.stop();
+            }
+        }
+
+        impl<B, REMAP, PIN> crate::dma::ReadDma<B, u8> for SpiRxDma<$SPIi, REMAP, PIN, $RCi>
+        where
+            B: StaticWriteBuffer<Word = u8>,
+        {
+            fn read(mut self, mut buffer: B) -> Transfer<W, B, Self> {
+                // NOTE(unsafe) We own the buffer now and we won't call other `&mut` on it
+                // until the end of the transfer.
+                let (ptr, len) = unsafe { buffer.static_write_buffer() };
+                self.channel.set_peripheral_address(
+                    unsafe { &(*$SPIi::ptr()).dr as *const _ as u32 },
+                    false,
+                );
+                self.channel.set_memory_address(ptr as u32, true);
+                self.channel.set_transfer_length(len);
+
+                atomic::compiler_fence(Ordering::Release);
+                self.channel.ch().cr.modify(|_, w| {
+                    w
+                        // memory to memory mode disabled
+                        .mem2mem()
+                        .clear_bit()
+                        // medium channel priority level
+                        .pl()
+                        .medium()
+                        // 8-bit memory size
+                        .msize()
+                        .bits8()
+                        // 8-bit peripheral size
+                        .psize()
+                        .bits8()
+                        // circular mode disabled
+                        .circ()
+                        .clear_bit()
+                        // write to memory
+                        .dir()
+                        .clear_bit()
+                });
+                self.start();
+
+                Transfer::w(buffer, self)
+            }
+        }
+
         impl<B, REMAP, PIN> crate::dma::WriteDma<B, u8> for SpiTxDma<$SPIi, REMAP, PIN, $TCi>
         where
             B: StaticReadBuffer<Word = u8>,
@@ -627,10 +744,93 @@ macro_rules! spi_dma {
                 Transfer::r(buffer, self)
             }
         }
+
+        impl<RXB, TXB, REMAP, PIN> crate::dma::ReadWriteDma<RXB, TXB, u8>
+            for SpiRxTxDma<$SPIi, REMAP, PIN, $RCi, $TCi>
+        where
+            RXB: StaticWriteBuffer<Word = u8>,
+            TXB: StaticReadBuffer<Word = u8>,
+        {
+            fn read_write(
+                mut self,
+                mut rxbuffer: RXB,
+                txbuffer: TXB,
+            ) -> Transfer<W, (RXB, TXB), Self> {
+                // NOTE(unsafe) We own the buffer now and we won't call other `&mut` on it
+                // until the end of the transfer.
+                let (rxptr, rxlen) = unsafe { rxbuffer.static_write_buffer() };
+                let (txptr, txlen) = unsafe { txbuffer.static_read_buffer() };
+
+                if rxlen != txlen {
+                    panic!("receive and send buffer lengths do not match!");
+                }
+
+                self.rxchannel.set_peripheral_address(
+                    unsafe { &(*$SPIi::ptr()).dr as *const _ as u32 },
+                    false,
+                );
+                self.rxchannel.set_memory_address(rxptr as u32, true);
+                self.rxchannel.set_transfer_length(rxlen);
+
+                self.txchannel.set_peripheral_address(
+                    unsafe { &(*$SPIi::ptr()).dr as *const _ as u32 },
+                    false,
+                );
+                self.txchannel.set_memory_address(txptr as u32, true);
+                self.txchannel.set_transfer_length(txlen);
+
+                atomic::compiler_fence(Ordering::Release);
+                self.rxchannel.ch().cr.modify(|_, w| {
+                    w
+                        // memory to memory mode disabled
+                        .mem2mem()
+                        .clear_bit()
+                        // medium channel priority level
+                        .pl()
+                        .medium()
+                        // 8-bit memory size
+                        .msize()
+                        .bits8()
+                        // 8-bit peripheral size
+                        .psize()
+                        .bits8()
+                        // circular mode disabled
+                        .circ()
+                        .clear_bit()
+                        // write to memory
+                        .dir()
+                        .clear_bit()
+                });
+                self.txchannel.ch().cr.modify(|_, w| {
+                    w
+                        // memory to memory mode disabled
+                        .mem2mem()
+                        .clear_bit()
+                        // medium channel priority level
+                        .pl()
+                        .medium()
+                        // 8-bit memory size
+                        .msize()
+                        .bits8()
+                        // 8-bit peripheral size
+                        .psize()
+                        .bits8()
+                        // circular mode disabled
+                        .circ()
+                        .clear_bit()
+                        // read from memory
+                        .dir()
+                        .set_bit()
+                });
+                self.start();
+
+                Transfer::w((rxbuffer, txbuffer), self)
+            }
+        }
     };
 }
 
-spi_dma!(SPI1, C3);
-spi_dma!(SPI2, C5);
+spi_dma!(SPI1, dma1::C2, dma1::C3);
+spi_dma!(SPI2, dma1::C4, dma1::C5);
 #[cfg(feature = "connectivity")]
-spi_dma!(SPI3, C2);
+spi_dma!(SPI3, dma2::C1, dma2::C2);

From 7138771b6bb7b658f91a47a1635d27cf9745bdd8 Mon Sep 17 00:00:00 2001
From: Florian Jung <flo@windfis.ch>
Date: Thu, 20 May 2021 23:57:11 +0200
Subject: [PATCH 2/5] Move SPI DMA enable to with_tx_dma and add release
 function

As per https://github.com/stm32-rs/stm32f1xx-hal/issues/334#issuecomment-843724427
---
 CHANGELOG.md |  2 ++
 src/spi.rs   | 65 +++++++++++++++++++++++++++++-----------------------
 2 files changed, 38 insertions(+), 29 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4013636e..240a6dd6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
   control over the timer
 - Added RxTxDma support support to the DMA infrastructure
 - Added DMA receive support for `SPI`
+- Added `release` functions to SPI DMA
 
 ### Fixed
 - Fix > 2 byte i2c reads
@@ -26,6 +27,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Changed
 - Use `cortex-m-rtic` instead of `cortex-m-rtfm` in the examples
+- Enable SPI DMA in `with_tx_dma`, not in `SpiTxDma::start`
 
 ## [v0.7.0]- 2020-10-17
 
diff --git a/src/spi.rs b/src/spi.rs
index 1f7f042b..c522b44b 100644
--- a/src/spi.rs
+++ b/src/spi.rs
@@ -579,10 +579,12 @@ macro_rules! spi_dma {
 
         impl<REMAP, PINS> Spi<$SPIi, REMAP, PINS, u8> {
             pub fn with_tx_dma(self, channel: $TCi) -> SpiTxDma<$SPIi, REMAP, PINS, $TCi> {
+                self.spi.cr2.modify(|_, w| w.txdmaen().set_bit());
                 let payload = SpiPayload { spi: self };
                 SpiTxDma { payload, channel }
             }
             pub fn with_rx_dma(self, channel: $RCi) -> SpiRxDma<$SPIi, REMAP, PINS, $RCi> {
+                self.spi.cr2.modify(|_, w| w.rxdmaen().set_bit());
                 let payload = SpiPayload { spi: self };
                 SpiRxDma { payload, channel }
             }
@@ -591,6 +593,9 @@ macro_rules! spi_dma {
                 rxchannel: $RCi,
                 txchannel: $TCi,
             ) -> SpiRxTxDma<$SPIi, REMAP, PINS, $RCi, $TCi> {
+                self.spi
+                    .cr2
+                    .modify(|_, w| w.rxdmaen().set_bit().txdmaen().set_bit());
                 let payload = SpiPayload { spi: self };
                 SpiRxTxDma {
                     payload,
@@ -600,60 +605,62 @@ macro_rules! spi_dma {
             }
         }
 
-        impl<REMAP, PINS> TransferPayload for SpiTxDma<$SPIi, REMAP, PINS, $TCi> {
-            fn start(&mut self) {
-                self.payload
+        impl<REMAP, PINS> SpiTxDma<$SPIi, REMAP, PINS, $TCi> {
+            pub fn release(self) -> (Spi<$SPIi, REMAP, PINS, u8>, $TCi) {
+                let SpiTxDma { payload, channel } = self;
+                payload.spi.spi.cr2.modify(|_, w| w.txdmaen().clear_bit());
+                (payload.spi, channel)
+            }
+        }
+
+        impl<REMAP, PINS> SpiRxDma<$SPIi, REMAP, PINS, $RCi> {
+            pub fn release(self) -> (Spi<$SPIi, REMAP, PINS, u8>, $RCi) {
+                let SpiRxDma { payload, channel } = self;
+                payload.spi.spi.cr2.modify(|_, w| w.rxdmaen().clear_bit());
+                (payload.spi, channel)
+            }
+        }
+
+        impl<REMAP, PINS> SpiRxTxDma<$SPIi, REMAP, PINS, $RCi, $TCi> {
+            pub fn release(self) -> (Spi<$SPIi, REMAP, PINS, u8>, $RCi, $TCi) {
+                let SpiRxTxDma {
+                    payload,
+                    rxchannel,
+                    txchannel,
+                } = self;
+                payload
                     .spi
                     .spi
                     .cr2
-                    .modify(|_, w| w.txdmaen().set_bit());
+                    .modify(|_, w| w.rxdmaen().clear_bit().txdmaen().clear_bit());
+                (payload.spi, rxchannel, txchannel)
+            }
+        }
+
+        impl<REMAP, PINS> TransferPayload for SpiTxDma<$SPIi, REMAP, PINS, $TCi> {
+            fn start(&mut self) {
                 self.channel.start();
             }
             fn stop(&mut self) {
-                self.payload
-                    .spi
-                    .spi
-                    .cr2
-                    .modify(|_, w| w.txdmaen().clear_bit());
                 self.channel.stop();
             }
         }
 
         impl<REMAP, PINS> TransferPayload for SpiRxDma<$SPIi, REMAP, PINS, $RCi> {
             fn start(&mut self) {
-                self.payload
-                    .spi
-                    .spi
-                    .cr2
-                    .modify(|_, w| w.rxdmaen().set_bit());
                 self.channel.start();
             }
             fn stop(&mut self) {
-                self.payload
-                    .spi
-                    .spi
-                    .cr2
-                    .modify(|_, w| w.rxdmaen().clear_bit());
                 self.channel.stop();
             }
         }
 
         impl<REMAP, PINS> TransferPayload for SpiRxTxDma<$SPIi, REMAP, PINS, $RCi, $TCi> {
             fn start(&mut self) {
-                self.payload
-                    .spi
-                    .spi
-                    .cr2
-                    .modify(|_, w| w.rxdmaen().set_bit().txdmaen().set_bit());
                 self.rxchannel.start();
                 self.txchannel.start();
             }
             fn stop(&mut self) {
-                self.payload
-                    .spi
-                    .spi
-                    .cr2
-                    .modify(|_, w| w.txdmaen().clear_bit().rxdmaen().clear_bit());
                 self.txchannel.stop();
                 self.rxchannel.stop();
             }

From e6796e07056fa898cfc73f46d38363a794ced4cd Mon Sep 17 00:00:00 2001
From: Florian Jung <flo@windfis.ch>
Date: Sat, 22 May 2021 18:30:33 +0200
Subject: [PATCH 3/5] Add dma::ReadWriteDma to the prelude

---
 src/prelude.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/prelude.rs b/src/prelude.rs
index ff349473..05c353e1 100644
--- a/src/prelude.rs
+++ b/src/prelude.rs
@@ -4,6 +4,7 @@ pub use crate::crc::CrcExt as _stm32_hal_crc_CrcExt;
 pub use crate::dma::CircReadDma as _stm32_hal_dma_CircReadDma;
 pub use crate::dma::DmaExt as _stm32_hal_dma_DmaExt;
 pub use crate::dma::ReadDma as _stm32_hal_dma_ReadDma;
+pub use crate::dma::ReadWriteDma as _stm32_hal_dma_ReadWriteDma;
 pub use crate::dma::WriteDma as _stm32_hal_dma_WriteDma;
 pub use crate::flash::FlashExt as _stm32_hal_flash_FlashExt;
 pub use crate::gpio::GpioExt as _stm32_hal_gpio_GpioExt;

From 866dafa461896c4f8d5312a344c18e933d82dcca Mon Sep 17 00:00:00 2001
From: Florian Jung <flo@windfis.ch>
Date: Mon, 24 May 2021 21:53:13 +0200
Subject: [PATCH 4/5] Remove SpiPayload wrapper

---
 src/spi.rs | 36 +++++++++++++++++-------------------
 1 file changed, 17 insertions(+), 19 deletions(-)

diff --git a/src/spi.rs b/src/spi.rs
index c522b44b..ca0cdceb 100644
--- a/src/spi.rs
+++ b/src/spi.rs
@@ -546,14 +546,10 @@ where
 
 // DMA
 
-pub struct SpiPayload<SPI, REMAP, PINS> {
-    spi: Spi<SPI, REMAP, PINS, u8>,
-}
-
-pub type SpiTxDma<SPI, REMAP, PINS, CHANNEL> = TxDma<SpiPayload<SPI, REMAP, PINS>, CHANNEL>;
-pub type SpiRxDma<SPI, REMAP, PINS, CHANNEL> = RxDma<SpiPayload<SPI, REMAP, PINS>, CHANNEL>;
+pub type SpiTxDma<SPI, REMAP, PINS, CHANNEL> = TxDma<Spi<SPI, REMAP, PINS, u8>, CHANNEL>;
+pub type SpiRxDma<SPI, REMAP, PINS, CHANNEL> = RxDma<Spi<SPI, REMAP, PINS, u8>, CHANNEL>;
 pub type SpiRxTxDma<SPI, REMAP, PINS, RXCHANNEL, TXCHANNEL> =
-    RxTxDma<SpiPayload<SPI, REMAP, PINS>, RXCHANNEL, TXCHANNEL>;
+    RxTxDma<Spi<SPI, REMAP, PINS, u8>, RXCHANNEL, TXCHANNEL>;
 
 macro_rules! spi_dma {
     ($SPIi:ident, $RCi:ty, $TCi:ty) => {
@@ -580,13 +576,17 @@ macro_rules! spi_dma {
         impl<REMAP, PINS> Spi<$SPIi, REMAP, PINS, u8> {
             pub fn with_tx_dma(self, channel: $TCi) -> SpiTxDma<$SPIi, REMAP, PINS, $TCi> {
                 self.spi.cr2.modify(|_, w| w.txdmaen().set_bit());
-                let payload = SpiPayload { spi: self };
-                SpiTxDma { payload, channel }
+                SpiTxDma {
+                    payload: self,
+                    channel,
+                }
             }
             pub fn with_rx_dma(self, channel: $RCi) -> SpiRxDma<$SPIi, REMAP, PINS, $RCi> {
                 self.spi.cr2.modify(|_, w| w.rxdmaen().set_bit());
-                let payload = SpiPayload { spi: self };
-                SpiRxDma { payload, channel }
+                SpiRxDma {
+                    payload: self,
+                    channel,
+                }
             }
             pub fn with_rx_tx_dma(
                 self,
@@ -596,9 +596,8 @@ macro_rules! spi_dma {
                 self.spi
                     .cr2
                     .modify(|_, w| w.rxdmaen().set_bit().txdmaen().set_bit());
-                let payload = SpiPayload { spi: self };
                 SpiRxTxDma {
-                    payload,
+                    payload: self,
                     rxchannel,
                     txchannel,
                 }
@@ -608,16 +607,16 @@ macro_rules! spi_dma {
         impl<REMAP, PINS> SpiTxDma<$SPIi, REMAP, PINS, $TCi> {
             pub fn release(self) -> (Spi<$SPIi, REMAP, PINS, u8>, $TCi) {
                 let SpiTxDma { payload, channel } = self;
-                payload.spi.spi.cr2.modify(|_, w| w.txdmaen().clear_bit());
-                (payload.spi, channel)
+                payload.spi.cr2.modify(|_, w| w.txdmaen().clear_bit());
+                (payload, channel)
             }
         }
 
         impl<REMAP, PINS> SpiRxDma<$SPIi, REMAP, PINS, $RCi> {
             pub fn release(self) -> (Spi<$SPIi, REMAP, PINS, u8>, $RCi) {
                 let SpiRxDma { payload, channel } = self;
-                payload.spi.spi.cr2.modify(|_, w| w.rxdmaen().clear_bit());
-                (payload.spi, channel)
+                payload.spi.cr2.modify(|_, w| w.rxdmaen().clear_bit());
+                (payload, channel)
             }
         }
 
@@ -629,11 +628,10 @@ macro_rules! spi_dma {
                     txchannel,
                 } = self;
                 payload
-                    .spi
                     .spi
                     .cr2
                     .modify(|_, w| w.rxdmaen().clear_bit().txdmaen().clear_bit());
-                (payload.spi, rxchannel, txchannel)
+                (payload, rxchannel, txchannel)
             }
         }
 

From eb83bd4a3ff733747ee14d5603d394511a629f87 Mon Sep 17 00:00:00 2001
From: Florian Jung <flo@windfis.ch>
Date: Tue, 25 May 2021 14:01:41 +0200
Subject: [PATCH 5/5] Add Spi1TxDma etc. type aliases

---
 src/spi.rs | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/spi.rs b/src/spi.rs
index ca0cdceb..42c29348 100644
--- a/src/spi.rs
+++ b/src/spi.rs
@@ -552,7 +552,11 @@ pub type SpiRxTxDma<SPI, REMAP, PINS, RXCHANNEL, TXCHANNEL> =
     RxTxDma<Spi<SPI, REMAP, PINS, u8>, RXCHANNEL, TXCHANNEL>;
 
 macro_rules! spi_dma {
-    ($SPIi:ident, $RCi:ty, $TCi:ty) => {
+    ($SPIi:ident, $RCi:ty, $TCi:ty, $rxdma:ident, $txdma:ident, $rxtxdma:ident) => {
+        pub type $rxdma<REMAP, PINS> = SpiRxDma<$SPIi, REMAP, PINS, $RCi>;
+        pub type $txdma<REMAP, PINS> = SpiTxDma<$SPIi, REMAP, PINS, $TCi>;
+        pub type $rxtxdma<REMAP, PINS> = SpiRxTxDma<$SPIi, REMAP, PINS, $RCi, $TCi>;
+
         impl<REMAP, PINS> Transmit for SpiTxDma<$SPIi, REMAP, PINS, $TCi> {
             type TxChannel = $TCi;
             type ReceivedWord = u8;
@@ -835,7 +839,7 @@ macro_rules! spi_dma {
     };
 }
 
-spi_dma!(SPI1, dma1::C2, dma1::C3);
-spi_dma!(SPI2, dma1::C4, dma1::C5);
+spi_dma!(SPI1, dma1::C2, dma1::C3, Spi1RxDma, Spi1TxDma, Spi1RxTxDma);
+spi_dma!(SPI2, dma1::C4, dma1::C5, Spi2RxDma, Spi2TxDma, Spi2RxTxDma);
 #[cfg(feature = "connectivity")]
-spi_dma!(SPI3, dma2::C1, dma2::C2);
+spi_dma!(SPI3, dma2::C1, dma2::C2, Spi3RxDma, Spi3TxDma, Spi3RxTxDma);