4 files changed, 125 insertions, 382 deletions

diff --git a/embassy-stm32/src/spi/mod.rs b/embassy-stm32/src/spi/mod.rs
index f39fc746d..d3d78e2a8 100644
--- a/embassy-stm32/src/spi/mod.rs
+++ b/embassy-stm32/src/spi/mod.rs
@@ -1,6 +1,7 @@
 #![macro_use]
 
 use crate::dma;
+use crate::dma::NoDma;
 use crate::gpio::sealed::{AFType, Pin};
 use crate::gpio::{AnyPin, NoPin, OptionalPin};
 use crate::pac::spi::{regs, vals};
@@ -9,6 +10,7 @@ use crate::rcc::RccPeripheral;
 use crate::time::Hertz;
 use core::future::Future;
 use core::marker::PhantomData;
+use core::ptr;
 use embassy::util::Unborrow;
 use embassy_hal_common::unborrow;
 use embassy_traits::spi as traits;
@@ -403,11 +405,121 @@ fn check_error_flags(sr: regs::Sr) -> Result<(), Error> {
     Ok(())
 }
 
+fn spin_until_tx_ready(regs: &'static crate::pac::spi::Spi) -> Result<(), Error> {
+    loop {
+        let sr = unsafe { regs.sr().read() };
+
+        check_error_flags(sr)?;
+
+        #[cfg(not(spi_v3))]
+        if sr.txe() {
+            return Ok(());
+        }
+        #[cfg(spi_v3)]
+        if sr.txp() {
+            return Ok(());
+        }
+    }
+}
+
+fn spin_until_rx_ready(regs: &'static crate::pac::spi::Spi) -> Result<(), Error> {
+    loop {
+        let sr = unsafe { regs.sr().read() };
+
+        check_error_flags(sr)?;
+
+        #[cfg(not(spi_v3))]
+        if sr.rxne() {
+            return Ok(());
+        }
+        #[cfg(spi_v3)]
+        if sr.rxp() {
+            return Ok(());
+        }
+    }
+}
+
 trait Word {}
 
 impl Word for u8 {}
 impl Word for u16 {}
 
+fn transfer_word<W: Word>(regs: &'static crate::pac::spi::Spi, tx_word: W) -> Result<W, Error> {
+    spin_until_tx_ready(regs)?;
+
+    unsafe {
+        ptr::write_volatile(regs.tx_ptr(), tx_word);
+
+        #[cfg(spi_v3)]
+        regs.cr1().modify(|reg| reg.set_cstart(true));
+    }
+
+    spin_until_rx_ready(regs)?;
+
+    let rx_word = unsafe { ptr::read_volatile(regs.rx_ptr()) };
+    return Ok(rx_word);
+}
+
+impl<'d, T: Instance> embedded_hal::blocking::spi::Write<u8> for Spi<'d, T, NoDma, NoDma> {
+    type Error = Error;
+
+    fn write(&mut self, words: &[u8]) -> Result<(), Self::Error> {
+        self.set_word_size(WordSize::EightBit);
+        let regs = T::regs();
+
+        for word in words.iter() {
+            let _ = transfer_word(regs, *word)?;
+        }
+
+        Ok(())
+    }
+}
+
+impl<'d, T: Instance> embedded_hal::blocking::spi::Transfer<u8> for Spi<'d, T, NoDma, NoDma> {
+    type Error = Error;
+
+    fn transfer<'w>(&mut self, words: &'w mut [u8]) -> Result<&'w [u8], Self::Error> {
+        self.set_word_size(WordSize::EightBit);
+        let regs = T::regs();
+
+        for word in words.iter_mut() {
+            *word = transfer_word(regs, *word)?;
+        }
+
+        Ok(words)
+    }
+}
+
+impl<'d, T: Instance> embedded_hal::blocking::spi::Write<u16> for Spi<'d, T, NoDma, NoDma> {
+    type Error = Error;
+
+    fn write(&mut self, words: &[u16]) -> Result<(), Self::Error> {
+        self.set_word_size(WordSize::SixteenBit);
+        let regs = T::regs();
+
+        for word in words.iter() {
+            let _ = transfer_word(regs, *word)?;
+        }
+
+        Ok(())
+    }
+}
+
+impl<'d, T: Instance> embedded_hal::blocking::spi::Transfer<u16> for Spi<'d, T, NoDma, NoDma> {
+    type Error = Error;
+
+    fn transfer<'w>(&mut self, words: &'w mut [u16]) -> Result<&'w [u16], Self::Error> {
+        self.set_word_size(WordSize::SixteenBit);
+        let regs = T::regs();
+
+        for word in words.iter_mut() {
+            *word = transfer_word(regs, *word)?;
+        }
+
+        Ok(words)
+    }
+}
+
 impl<'d, T: Instance, Tx, Rx> traits::Spi<u8> for Spi<'d, T, Tx, Rx> {
     type Error = Error;
 }
diff --git a/embassy-stm32/src/spi/v1.rs b/embassy-stm32/src/spi/v1.rs
index efe7e468c..92449ea80 100644
--- a/embassy-stm32/src/spi/v1.rs
+++ b/embassy-stm32/src/spi/v1.rs
@@ -1,15 +1,10 @@
 #![macro_use]
 
-use crate::dma::NoDma;
-use crate::spi::{
-    check_error_flags, Error, Instance, RegsExt, RxDmaChannel, TxDmaChannel, WordSize,
-};
-use core::ptr;
 pub use embedded_hal::blocking;
 pub use embedded_hal::spi::{Mode, Phase, Polarity, MODE_0, MODE_1, MODE_2, MODE_3};
 use futures::future::join3;
 
-use super::Spi;
+use super::*;
 
 impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
     pub(super) async fn write_dma_u8(&mut self, write: &[u8]) -> Result<(), Error>
@@ -155,99 +150,3 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
         }
     }
 }
-
-impl<'d, T: Instance> embedded_hal::blocking::spi::Write<u8> for Spi<'d, T, NoDma, NoDma> {
-    type Error = Error;
-
-    fn write(&mut self, words: &[u8]) -> Result<(), Self::Error> {
-        self.set_word_size(WordSize::EightBit);
-        let regs = T::regs();
-
-        for word in words.iter() {
-            write_word(regs, *word)?;
-            let _: u8 = read_word(regs)?;
-        }
-
-        Ok(())
-    }
-}
-
-impl<'d, T: Instance> embedded_hal::blocking::spi::Transfer<u8> for Spi<'d, T, NoDma, NoDma> {
-    type Error = Error;
-
-    fn transfer<'w>(&mut self, words: &'w mut [u8]) -> Result<&'w [u8], Self::Error> {
-        self.set_word_size(WordSize::EightBit);
-        let regs = T::regs();
-
-        for word in words.iter_mut() {
-            write_word(regs, *word)?;
-            *word = read_word(regs)?;
-        }
-
-        Ok(words)
-    }
-}
-
-impl<'d, T: Instance> embedded_hal::blocking::spi::Write<u16> for Spi<'d, T, NoDma, NoDma> {
-    type Error = Error;
-
-    fn write(&mut self, words: &[u16]) -> Result<(), Self::Error> {
-        self.set_word_size(WordSize::SixteenBit);
-        let regs = T::regs();
-
-        for word in words.iter() {
-            write_word(regs, *word)?;
-            let _: u8 = read_word(regs)?;
-        }
-
-        Ok(())
-    }
-}
-
-impl<'d, T: Instance> embedded_hal::blocking::spi::Transfer<u16> for Spi<'d, T, NoDma, NoDma> {
-    type Error = Error;
-
-    fn transfer<'w>(&mut self, words: &'w mut [u16]) -> Result<&'w [u16], Self::Error> {
-        self.set_word_size(WordSize::SixteenBit);
-        let regs = T::regs();
-
-        for word in words.iter_mut() {
-            write_word(regs, *word)?;
-            *word = read_word(regs)?;
-        }
-
-        Ok(words)
-    }
-}
-
-use super::Word;
-
-fn write_word<W: Word>(regs: &'static crate::pac::spi::Spi, word: W) -> Result<(), Error> {
-    loop {
-        let sr = unsafe { regs.sr().read() };
-
-        check_error_flags(sr)?;
-
-        if sr.txe() {
-            unsafe {
-                ptr::write_volatile(regs.tx_ptr(), word);
-            }
-            return Ok(());
-        }
-    }
-}
-
-/// Read a single word blocking. Assumes word size have already been set.
-fn read_word<W: Word>(regs: &'static crate::pac::spi::Spi) -> Result<W, Error> {
-    loop {
-        let sr = unsafe { regs.sr().read() };
-
-        check_error_flags(sr)?;
-
-        if sr.rxne() {
-            unsafe {
-                return Ok(ptr::read_volatile(regs.rx_ptr()));
-            }
-        }
-    }
-}
diff --git a/embassy-stm32/src/spi/v2.rs b/embassy-stm32/src/spi/v2.rs
index e905a1b9c..de78676c2 100644
--- a/embassy-stm32/src/spi/v2.rs
+++ b/embassy-stm32/src/spi/v2.rs
@@ -1,14 +1,9 @@
 #![macro_use]
 
-use crate::dma::NoDma;
-use crate::spi::{
-    check_error_flags, Error, Instance, RegsExt, RxDmaChannel, TxDmaChannel, WordSize,
-};
-use core::ptr;
 pub use embedded_hal::spi::{Mode, Phase, Polarity, MODE_0, MODE_1, MODE_2, MODE_3};
 use futures::future::{join, join3};
 
-use super::Spi;
+use super::*;
 
 impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
     pub(super) async fn write_dma_u8(&mut self, write: &[u8]) -> Result<(), Error>
@@ -100,7 +95,11 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
         Ok(())
     }
 
-    pub(super) async fn read_write_dma_u8(&mut self, read: &mut [u8], write: &[u8]) -> Result<(), Error>
+    pub(super) async fn read_write_dma_u8(
+        &mut self,
+        read: &mut [u8],
+        write: &[u8],
+    ) -> Result<(), Error>
     where
         Tx: TxDmaChannel<T>,
         Rx: RxDmaChannel<T>,
@@ -170,100 +169,3 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
         }
     }
 }
-
-use super::Word;
-
-/// Write a single word blocking. Assumes word size have already been set.
-fn write_word<W: Word>(regs: &'static crate::pac::spi::Spi, word: W) -> Result<(), Error> {
-    loop {
-        let sr = unsafe { regs.sr().read() };
-
-        check_error_flags(sr)?;
-
-        if sr.txe() {
-            unsafe {
-                ptr::write_volatile(regs.tx_ptr(), word);
-            }
-            return Ok(());
-        }
-    }
-}
-
-/// Read a single word blocking. Assumes word size have already been set.
-fn read_word<W: Word>(regs: &'static crate::pac::spi::Spi) -> Result<W, Error> {
-    loop {
-        let sr = unsafe { regs.sr().read() };
-
-        check_error_flags(sr)?;
-
-        if sr.rxne() {
-            unsafe {
-                return Ok(ptr::read_volatile(regs.rx_ptr()));
-            }
-        }
-    }
-}
-
-impl<'d, T: Instance, Rx> embedded_hal::blocking::spi::Write<u8> for Spi<'d, T, NoDma, Rx> {
-    type Error = Error;
-
-    fn write(&mut self, words: &[u8]) -> Result<(), Self::Error> {
-        self.set_word_size(WordSize::EightBit);
-        let regs = T::regs();
-
-        for word in words.iter() {
-            write_word(regs, *word)?;
-            let _: u8 = read_word(regs)?;
-        }
-
-        Ok(())
-    }
-}
-
-impl<'d, T: Instance> embedded_hal::blocking::spi::Transfer<u8> for Spi<'d, T, NoDma, NoDma> {
-    type Error = Error;
-
-    fn transfer<'w>(&mut self, words: &'w mut [u8]) -> Result<&'w [u8], Self::Error> {
-        self.set_word_size(WordSize::EightBit);
-        let regs = T::regs();
-
-        for word in words.iter_mut() {
-            write_word(regs, *word)?;
-            *word = read_word(regs)?;
-        }
-
-        Ok(words)
-    }
-}
-
-impl<'d, T: Instance, Rx> embedded_hal::blocking::spi::Write<u16> for Spi<'d, T, NoDma, Rx> {
-    type Error = Error;
-
-    fn write(&mut self, words: &[u16]) -> Result<(), Self::Error> {
-        self.set_word_size(WordSize::SixteenBit);
-        let regs = T::regs();
-
-        for word in words.iter() {
-            write_word(regs, *word)?;
-            let _: u16 = read_word(regs)?;
-        }
-
-        Ok(())
-    }
-}
-
-impl<'d, T: Instance> embedded_hal::blocking::spi::Transfer<u16> for Spi<'d, T, NoDma, NoDma> {
-    type Error = Error;
-
-    fn transfer<'w>(&mut self, words: &'w mut [u16]) -> Result<&'w [u16], Self::Error> {
-        self.set_word_size(WordSize::SixteenBit);
-        let regs = T::regs();
-
-        for word in words.iter_mut() {
-            write_word(regs, *word)?;
-            *word = read_word(regs)?;
-        }
-
-        Ok(words)
-    }
-}
diff --git a/embassy-stm32/src/spi/v3.rs b/embassy-stm32/src/spi/v3.rs
index cbe2861e0..ef0f23063 100644
--- a/embassy-stm32/src/spi/v3.rs
+++ b/embassy-stm32/src/spi/v3.rs
@@ -1,15 +1,9 @@
 #![macro_use]
 
-use crate::dma::NoDma;
-use crate::spi::{
-    check_error_flags, Error, Instance, RegsExt, RxDmaChannel, TxDmaChannel, WordSize,
-};
-use core::ptr;
 pub use embedded_hal::spi::{Mode, Phase, Polarity, MODE_0, MODE_1, MODE_2, MODE_3};
-
 use futures::future::join3;
 
-use super::Spi;
+use super::*;
 
 impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
     pub(super) async fn write_dma_u8(&mut self, write: &[u8]) -> Result<(), Error>
@@ -105,7 +99,11 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
         Ok(())
     }
 
-    pub(super) async fn read_write_dma_u8(&mut self, read: &mut [u8], write: &[u8]) -> Result<(), Error>
+    pub(super) async fn read_write_dma_u8(
+        &mut self,
+        read: &mut [u8],
+        write: &[u8],
+    ) -> Result<(), Error>
     where
         Tx: TxDmaChannel<T>,
         Rx: RxDmaChannel<T>,
@@ -173,171 +171,3 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
         }
     }
 }
-
-impl<'d, T: Instance> embedded_hal::blocking::spi::Write<u8> for Spi<'d, T, NoDma, NoDma> {
-    type Error = Error;
-
-    fn write(&mut self, words: &[u8]) -> Result<(), Self::Error> {
-        self.set_word_size(WordSize::EightBit);
-        let regs = T::regs();
-
-        for word in words.iter() {
-            while unsafe { !regs.sr().read().txp() } {
-                // spin
-            }
-            unsafe {
-                ptr::write_volatile(regs.tx_ptr(), *word);
-                regs.cr1().modify(|reg| reg.set_cstart(true));
-            }
-            loop {
-                let sr = unsafe { regs.sr().read() };
-                if sr.tifre() {
-                    return Err(Error::Framing);
-                }
-                if sr.ovr() {
-                    return Err(Error::Overrun);
-                }
-                if sr.crce() {
-                    return Err(Error::Crc);
-                }
-                if !sr.txp() {
-                    // loop waiting for TXE
-                    continue;
-                }
-                break;
-            }
-            unsafe {
-                // discard read to prevent pverrun.
-                let _: u8 = ptr::read_volatile(T::regs().rx_ptr());
-            }
-        }
-
-        while unsafe { !regs.sr().read().txc() } {
-            // spin
-        }
-
-        Ok(())
-    }
-}
-
-impl<'d, T: Instance> embedded_hal::blocking::spi::Transfer<u8> for Spi<'d, T, NoDma, NoDma> {
-    type Error = Error;
-
-    fn transfer<'w>(&mut self, words: &'w mut [u8]) -> Result<&'w [u8], Self::Error> {
-        self.set_word_size(WordSize::EightBit);
-        let regs = T::regs();
-
-        for word in words.iter_mut() {
-            unsafe {
-                regs.cr1().modify(|reg| {
-                    reg.set_ssi(false);
-                });
-            }
-            while unsafe { !regs.sr().read().txp() } {
-                // spin
-            }
-            unsafe {
-                ptr::write_volatile(T::regs().tx_ptr(), *word);
-                regs.cr1().modify(|reg| reg.set_cstart(true));
-            }
-            loop {
-                let sr = unsafe { regs.sr().read() };
-
-                if sr.rxp() {
-                    break;
-                }
-
-                check_error_flags(sr)?;
-            }
-            unsafe {
-                *word = ptr::read_volatile(T::regs().rx_ptr());
-            }
-            let sr = unsafe { regs.sr().read() };
-            check_error_flags(sr)?;
-        }
-
-        Ok(words)
-    }
-}
-
-impl<'d, T: Instance> embedded_hal::blocking::spi::Write<u16> for Spi<'d, T, NoDma, NoDma> {
-    type Error = Error;
-
-    fn write(&mut self, words: &[u16]) -> Result<(), Self::Error> {
-        self.set_word_size(WordSize::SixteenBit);
-        let regs = T::regs();
-
-        for word in words.iter() {
-            while unsafe { !regs.sr().read().txp() } {
-                // spin
-            }
-            unsafe {
-                let txdr = regs.txdr().ptr() as *mut u16;
-                ptr::write_volatile(txdr, *word);
-                regs.cr1().modify(|reg| reg.set_cstart(true));
-            }
-            loop {
-                let sr = unsafe { regs.sr().read() };
-
-                check_error_flags(sr)?;
-
-                if !sr.txp() {
-                    // loop waiting for TXE
-                    continue;
-                }
-                break;
-            }
-
-            unsafe {
-                let rxdr = regs.rxdr().ptr() as *const u8;
-                // discard read to prevent pverrun.
-                let _ = ptr::read_volatile(rxdr);
-            }
-        }
-
-        while unsafe { !regs.sr().read().txc() } {
-            // spin
-        }
-
-        Ok(())
-    }
-}
-
-impl<'d, T: Instance> embedded_hal::blocking::spi::Transfer<u16> for Spi<'d, T, NoDma, NoDma> {
-    type Error = Error;
-
-    fn transfer<'w>(&mut self, words: &'w mut [u16]) -> Result<&'w [u16], Self::Error> {
-        self.set_word_size(WordSize::SixteenBit);
-        let regs = T::regs();
-
-        for word in words.iter_mut() {
-            while unsafe { !regs.sr().read().txp() } {
-                // spin
-            }
-            unsafe {
-                let txdr = regs.txdr().ptr() as *mut u16;
-                ptr::write_volatile(txdr, *word);
-                regs.cr1().modify(|reg| reg.set_cstart(true));
-            }
-
-            loop {
-                let sr = unsafe { regs.sr().read() };
-
-                if sr.rxp() {
-                    break;
-                }
-
-                check_error_flags(sr)?;
-            }
-
-            unsafe {
-                let rxdr = regs.rxdr().ptr() as *const u16;
-                *word = ptr::read_volatile(rxdr);
-            }
-            let sr = unsafe { regs.sr().read() };
-            check_error_flags(sr)?;
-        }
-
-        Ok(words)
-    }
-}