stm32/i2c: WIP async i2cv1

STM32 I2C: expose async API without needing "time" feature.

cyw43/src/control.rs

@@ -1,4 +1,5 @@
 use core::cmp::{max, min};
+use core::iter::zip;
 
 use embassy_net_driver_channel as ch;
 use embassy_net_driver_channel::driver::{HardwareAddress, LinkState};
@@ -16,6 +17,12 @@ pub struct Error {
     pub status: u32,
 }
 
+#[derive(Debug)]
+pub enum AddMulticastAddressError {
+    NotMulticast,
+    NoFreeSlots,
+}
+
 pub struct Control<'a> {
     state_ch: ch::StateRunner<'a>,
     events: &'a Events,
@@ -316,6 +323,54 @@ impl<'a> Control<'a> {
         self.set_iovar_u32x2("bss", 0, 1).await; // bss = BSS_UP
     }
 
+    /// Add specified address to the list of hardware addresses the device
+    /// listens on. The address must be a Group address (I/G bit set). Up
+    /// to 10 addresses are supported by the firmware. Returns the number of
+    /// address slots filled after adding, or an error.
+    pub async fn add_multicast_address(&mut self, address: [u8; 6]) -> Result<usize, AddMulticastAddressError> {
+        // The firmware seems to ignore non-multicast addresses, so let's
+        // prevent the user from adding them and wasting space.
+        if address[0] & 0x01 != 1 {
+            return Err(AddMulticastAddressError::NotMulticast);
+        }
+
+        let mut buf = [0; 64];
+        self.get_iovar("mcast_list", &mut buf).await;
+
+        let n = u32::from_le_bytes(buf[..4].try_into().unwrap()) as usize;
+        let (used, free) = buf[4..].split_at_mut(n * 6);
+
+        if used.chunks(6).any(|a| a == address) {
+            return Ok(n);
+        }
+
+        if free.len() < 6 {
+            return Err(AddMulticastAddressError::NoFreeSlots);
+        }
+
+        free[..6].copy_from_slice(&address);
+        let n = n + 1;
+        buf[..4].copy_from_slice(&(n as u32).to_le_bytes());
+
+        self.set_iovar_v::<80>("mcast_list", &buf).await;
+        Ok(n)
+    }
+
+    /// Retrieve the list of configured multicast hardware addresses.
+    pub async fn list_mulistcast_addresses(&mut self, result: &mut [[u8; 6]; 10]) -> usize {
+        let mut buf = [0; 64];
+        self.get_iovar("mcast_list", &mut buf).await;
+
+        let n = u32::from_le_bytes(buf[..4].try_into().unwrap()) as usize;
+        let used = &buf[4..][..n * 6];
+
+        for (addr, output) in zip(used.chunks(6), result.iter_mut()) {
+            output.copy_from_slice(addr)
+        }
+
+        n
+    }
+
     async fn set_iovar_u32x2(&mut self, name: &str, val1: u32, val2: u32) {
         let mut buf = [0; 8];
         buf[0..4].copy_from_slice(&val1.to_le_bytes());

cyw43/src/lib.rs

@@ -27,7 +27,7 @@ use ioctl::IoctlState;
 
 use crate::bus::Bus;
 pub use crate::bus::SpiBusCyw43;
-pub use crate::control::{Control, Error as ControlError, Scanner};
+pub use crate::control::{AddMulticastAddressError, Control, Error as ControlError, Scanner};
 pub use crate::runner::Runner;
 pub use crate::structs::BssInfo;
 

embassy-executor/src/raw/mod.rs

@@ -11,7 +11,8 @@
 #[cfg_attr(not(target_has_atomic = "ptr"), path = "run_queue_critical_section.rs")]
 mod run_queue;
 
-#[cfg_attr(target_has_atomic = "8", path = "state_atomics.rs")]
+#[cfg_attr(all(cortex_m, target_has_atomic = "8"), path = "state_atomics_arm.rs")]
+#[cfg_attr(all(not(cortex_m), target_has_atomic = "8"), path = "state_atomics.rs")]
 #[cfg_attr(not(target_has_atomic = "8"), path = "state_critical_section.rs")]
 mod state;
 

embassy-executor/src/raw/state_atomics_arm.rs

@@ -0,0 +1,103 @@
+use core::arch::asm;
+use core::sync::atomic::{compiler_fence, AtomicBool, AtomicU32, Ordering};
+
+// Must be kept in sync with the layout of `State`!
+pub(crate) const STATE_SPAWNED: u32 = 1 << 0;
+pub(crate) const STATE_RUN_QUEUED: u32 = 1 << 8;
+
+#[repr(C, align(4))]
+pub(crate) struct State {
+    /// Task is spawned (has a future)
+    spawned: AtomicBool,
+    /// Task is in the executor run queue
+    run_queued: AtomicBool,
+    /// Task is in the executor timer queue
+    timer_queued: AtomicBool,
+    pad: AtomicBool,
+}
+
+impl State {
+    pub const fn new() -> State {
+        Self {
+            spawned: AtomicBool::new(false),
+            run_queued: AtomicBool::new(false),
+            timer_queued: AtomicBool::new(false),
+            pad: AtomicBool::new(false),
+        }
+    }
+
+    fn as_u32(&self) -> &AtomicU32 {
+        unsafe { &*(self as *const _ as *const AtomicU32) }
+    }
+
+    /// If task is idle, mark it as spawned + run_queued and return true.
+    #[inline(always)]
+    pub fn spawn(&self) -> bool {
+        compiler_fence(Ordering::Release);
+        let r = self
+            .as_u32()
+            .compare_exchange(
+                0,
+                STATE_SPAWNED | STATE_RUN_QUEUED,
+                Ordering::Relaxed,
+                Ordering::Relaxed,
+            )
+            .is_ok();
+        compiler_fence(Ordering::Acquire);
+        r
+    }
+
+    /// Unmark the task as spawned.
+    #[inline(always)]
+    pub fn despawn(&self) {
+        compiler_fence(Ordering::Release);
+        self.spawned.store(false, Ordering::Relaxed);
+    }
+
+    /// Mark the task as run-queued if it's spawned and isn't already run-queued. Return true on success.
+    #[inline(always)]
+    pub fn run_enqueue(&self) -> bool {
+        unsafe {
+            loop {
+                let state: u32;
+                asm!("ldrex {}, [{}]", out(reg) state, in(reg) self, options(nostack));
+
+                if (state & STATE_RUN_QUEUED != 0) || (state & STATE_SPAWNED == 0) {
+                    asm!("clrex", options(nomem, nostack));
+                    return false;
+                }
+
+                let outcome: usize;
+                let new_state = state | STATE_RUN_QUEUED;
+                asm!("strex {}, {}, [{}]", out(reg) outcome, in(reg) new_state, in(reg) self, options(nostack));
+                if outcome == 0 {
+                    return true;
+                }
+            }
+        }
+    }
+
+    /// Unmark the task as run-queued. Return whether the task is spawned.
+    #[inline(always)]
+    pub fn run_dequeue(&self) -> bool {
+        compiler_fence(Ordering::Release);
+
+        let r = self.spawned.load(Ordering::Relaxed);
+        self.run_queued.store(false, Ordering::Relaxed);
+        r
+    }
+
+    /// Mark the task as timer-queued. Return whether it was newly queued (i.e. not queued before)
+    #[cfg(feature = "integrated-timers")]
+    #[inline(always)]
+    pub fn timer_enqueue(&self) -> bool {
+        !self.timer_queued.swap(true, Ordering::Relaxed)
+    }
+
+    /// Unmark the task as timer-queued.
+    #[cfg(feature = "integrated-timers")]
+    #[inline(always)]
+    pub fn timer_dequeue(&self) {
+        self.timer_queued.store(false, Ordering::Relaxed);
+    }
+}

embassy-stm32/Cargo.toml

@@ -58,7 +58,7 @@ rand_core = "0.6.3"
 sdio-host = "0.5.0"
 embedded-sdmmc = { git = "https://github.com/embassy-rs/embedded-sdmmc-rs", rev = "a4f293d3a6f72158385f79c98634cb8a14d0d2fc", optional = true }
 critical-section = "1.1"
-stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-fbb8f77326dd066aa6c0d66b3b46e76a569dda8b" }
+stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-f6d1ffc1a25f208b5cd6b1024bff246592da1949" }
 vcell = "0.1.3"
 bxcan = "0.7.0"
 nb = "1.0.0"
@@ -76,7 +76,7 @@ critical-section = { version = "1.1", features = ["std"] }
 [build-dependencies]
 proc-macro2 = "1.0.36"
 quote = "1.0.15"
-stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-fbb8f77326dd066aa6c0d66b3b46e76a569dda8b", default-features = false, features = ["metadata"]}
+stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-f6d1ffc1a25f208b5cd6b1024bff246592da1949", default-features = false, features = ["metadata"]}
 
 
 [features]

embassy-stm32/build.rs

@@ -1137,6 +1137,23 @@ fn main() {
         }
     }
 
+    // ========
+    // Write peripheral_interrupts module.
+    let mut mt = TokenStream::new();
+    for p in METADATA.peripherals {
+        let mut pt = TokenStream::new();
+
+        for irq in p.interrupts {
+            let iname = format_ident!("{}", irq.interrupt);
+            let sname = format_ident!("{}", irq.signal);
+            pt.extend(quote!(pub type #sname = crate::interrupt::typelevel::#iname;));
+        }
+
+        let pname = format_ident!("{}", p.name);
+        mt.extend(quote!(pub mod #pname { #pt }));
+    }
+    g.extend(quote!(#[allow(non_camel_case_types)] pub mod peripheral_interrupts { #mt }));
+
     // ========
     // Write foreach_foo! macrotables
 
@@ -1295,6 +1312,9 @@ fn main() {
 
     let mut m = String::new();
 
+    // DO NOT ADD more macros like these.
+    // These turned to be a bad idea!
+    // Instead, make build.rs generate the final code.
     make_table(&mut m, "foreach_flash_region", &flash_regions_table);
     make_table(&mut m, "foreach_interrupt", &interrupts_table);
     make_table(&mut m, "foreach_peripheral", &peripherals_table);

embassy-stm32/src/i2c/mod.rs

@@ -1,11 +1,14 @@
 #![macro_use]
 
+use core::marker::PhantomData;
+
 use crate::interrupt;
 
 #[cfg_attr(i2c_v1, path = "v1.rs")]
 #[cfg_attr(i2c_v2, path = "v2.rs")]
 mod _version;
 pub use _version::*;
+use embassy_sync::waitqueue::AtomicWaker;
 
 use crate::peripherals;
 
@@ -23,6 +26,20 @@ pub enum Error {
 
 pub(crate) mod sealed {
     use super::*;
+
+    pub struct State {
+        #[allow(unused)]
+        pub waker: AtomicWaker,
+    }
+
+    impl State {
+        pub const fn new() -> Self {
+            Self {
+                waker: AtomicWaker::new(),
+            }
+        }
+    }
+
     pub trait Instance: crate::rcc::RccPeripheral {
         fn regs() -> crate::pac::i2c::I2c;
         fn state() -> &'static State;
@@ -30,7 +47,8 @@ pub(crate) mod sealed {
 }
 
 pub trait Instance: sealed::Instance + 'static {
-    type Interrupt: interrupt::typelevel::Interrupt;
+    type EventInterrupt: interrupt::typelevel::Interrupt;
+    type ErrorInterrupt: interrupt::typelevel::Interrupt;
 }
 
 pin_trait!(SclPin, Instance);
@@ -38,21 +56,148 @@ pin_trait!(SdaPin, Instance);
 dma_trait!(RxDma, Instance);
 dma_trait!(TxDma, Instance);
 
-foreach_interrupt!(
-    ($inst:ident, i2c, $block:ident, EV, $irq:ident) => {
+/// Interrupt handler.
+pub struct EventInterruptHandler<T: Instance> {
+    _phantom: PhantomData<T>,
+}
+
+impl<T: Instance> interrupt::typelevel::Handler<T::EventInterrupt> for EventInterruptHandler<T> {
+    unsafe fn on_interrupt() {
+        _version::on_interrupt::<T>()
+    }
+}
+
+pub struct ErrorInterruptHandler<T: Instance> {
+    _phantom: PhantomData<T>,
+}
+
+impl<T: Instance> interrupt::typelevel::Handler<T::ErrorInterrupt> for ErrorInterruptHandler<T> {
+    unsafe fn on_interrupt() {
+        _version::on_interrupt::<T>()
+    }
+}
+
+foreach_peripheral!(
+    (i2c, $inst:ident) => {
         impl sealed::Instance for peripherals::$inst {
             fn regs() -> crate::pac::i2c::I2c {
                 crate::pac::$inst
             }
 
-            fn state() -> &'static State {
-                static STATE: State = State::new();
+            fn state() -> &'static sealed::State {
+                static STATE: sealed::State = sealed::State::new();
                 &STATE
             }
         }
 
         impl Instance for peripherals::$inst {
-            type Interrupt = crate::interrupt::typelevel::$irq;
+            type EventInterrupt = crate::_generated::peripheral_interrupts::$inst::EV;
+            type ErrorInterrupt = crate::_generated::peripheral_interrupts::$inst::ER;
         }
     };
 );
+
+mod eh02 {
+    use super::*;
+
+    impl<'d, T: Instance> embedded_hal_02::blocking::i2c::Read for I2c<'d, T> {
+        type Error = Error;
+
+        fn read(&mut self, address: u8, buffer: &mut [u8]) -> Result<(), Self::Error> {
+            self.blocking_read(address, buffer)
+        }
+    }
+
+    impl<'d, T: Instance> embedded_hal_02::blocking::i2c::Write for I2c<'d, T> {
+        type Error = Error;
+
+        fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Self::Error> {
+            self.blocking_write(address, write)
+        }
+    }
+
+    impl<'d, T: Instance> embedded_hal_02::blocking::i2c::WriteRead for I2c<'d, T> {
+        type Error = Error;
+
+        fn write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Self::Error> {
+            self.blocking_write_read(address, write, read)
+        }
+    }
+}
+
+#[cfg(feature = "unstable-traits")]
+mod eh1 {
+    use super::*;
+    use crate::dma::NoDma;
+
+    impl embedded_hal_1::i2c::Error for Error {
+        fn kind(&self) -> embedded_hal_1::i2c::ErrorKind {
+            match *self {
+                Self::Bus => embedded_hal_1::i2c::ErrorKind::Bus,
+                Self::Arbitration => embedded_hal_1::i2c::ErrorKind::ArbitrationLoss,
+                Self::Nack => {
+                    embedded_hal_1::i2c::ErrorKind::NoAcknowledge(embedded_hal_1::i2c::NoAcknowledgeSource::Unknown)
+                }
+                Self::Timeout => embedded_hal_1::i2c::ErrorKind::Other,
+                Self::Crc => embedded_hal_1::i2c::ErrorKind::Other,
+                Self::Overrun => embedded_hal_1::i2c::ErrorKind::Overrun,
+                Self::ZeroLengthTransfer => embedded_hal_1::i2c::ErrorKind::Other,
+            }
+        }
+    }
+
+    impl<'d, T: Instance, TXDMA, RXDMA> embedded_hal_1::i2c::ErrorType for I2c<'d, T, TXDMA, RXDMA> {
+        type Error = Error;
+    }
+
+    impl<'d, T: Instance> embedded_hal_1::i2c::I2c for I2c<'d, T, NoDma, NoDma> {
+        fn read(&mut self, address: u8, read: &mut [u8]) -> Result<(), Self::Error> {
+            self.blocking_read(address, read)
+        }
+
+        fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Self::Error> {
+            self.blocking_write(address, write)
+        }
+
+        fn write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Self::Error> {
+            self.blocking_write_read(address, write, read)
+        }
+
+        fn transaction(
+            &mut self,
+            _address: u8,
+            _operations: &mut [embedded_hal_1::i2c::Operation<'_>],
+        ) -> Result<(), Self::Error> {
+            todo!();
+        }
+    }
+}
+
+#[cfg(all(feature = "unstable-traits", feature = "nightly", feature = "time"))]
+mod eha {
+    use super::*;
+
+    impl<'d, T: Instance, TXDMA: TxDma<T>, RXDMA: RxDma<T>> embedded_hal_async::i2c::I2c for I2c<'d, T, TXDMA, RXDMA> {
+        async fn read(&mut self, address: u8, read: &mut [u8]) -> Result<(), Self::Error> {
+            self.read(address, read).await
+        }
+
+        async fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Self::Error> {
+            self.write(address, write).await
+        }
+
+        async fn write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Self::Error> {
+            self.write_read(address, write, read).await
+        }
+
+        async fn transaction(
+            &mut self,
+            address: u8,
+            operations: &mut [embedded_hal_1::i2c::Operation<'_>],
+        ) -> Result<(), Self::Error> {
+            let _ = address;
+            let _ = operations;
+            todo!()
+        }
+    }
+}

embassy-stm32/src/i2c/v1.rs

@@ -1,23 +1,33 @@
+use core::future::poll_fn;
 use core::marker::PhantomData;
+use core::task::Poll;
 
 use embassy_embedded_hal::SetConfig;
+use embassy_futures::select::{select, Either};
+use embassy_hal_internal::drop::OnDrop;
 use embassy_hal_internal::{into_ref, PeripheralRef};
 
-use crate::dma::NoDma;
+use super::*;
+use crate::dma::{NoDma, Transfer};
 use crate::gpio::sealed::AFType;
 use crate::gpio::Pull;
-use crate::i2c::{Error, Instance, SclPin, SdaPin};
+use crate::interrupt::typelevel::Interrupt;
 use crate::pac::i2c;
 use crate::time::Hertz;
 use crate::{interrupt, Peripheral};
 
-/// Interrupt handler.
-pub struct InterruptHandler<T: Instance> {
-    _phantom: PhantomData<T>,
-}
-
-impl<T: Instance> interrupt::typelevel::Handler<T::Interrupt> for InterruptHandler<T> {
-    unsafe fn on_interrupt() {}
+pub unsafe fn on_interrupt<T: Instance>() {
+    let regs = T::regs();
+    // i2c v2 only woke the task on transfer complete interrupts. v1 uses interrupts for a bunch of
+    // other stuff, so we wake the task on every interrupt.
+    T::state().waker.wake();
+    critical_section::with(|_| {
+        // Clear event interrupt flag.
+        regs.cr2().modify(|w| {
+            w.set_itevten(false);
+            w.set_iterren(false);
+        });
+    });
 }
 
 #[non_exhaustive]
@@ -27,14 +37,6 @@ pub struct Config {
     pub scl_pullup: bool,
 }
 
-pub struct State {}
-
-impl State {
-    pub(crate) const fn new() -> Self {
-        Self {}
-    }
-}
-
 pub struct I2c<'d, T: Instance, TXDMA = NoDma, RXDMA = NoDma> {
     phantom: PhantomData<&'d mut T>,
     #[allow(dead_code)]
@@ -48,7 +50,9 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         _peri: impl Peripheral<P = T> + 'd,
         scl: impl Peripheral<P = impl SclPin<T>> + 'd,
         sda: impl Peripheral<P = impl SdaPin<T>> + 'd,
-        _irq: impl interrupt::typelevel::Binding<T::Interrupt, InterruptHandler<T>> + 'd,
+        _irq: impl interrupt::typelevel::Binding<T::EventInterrupt, EventInterruptHandler<T>>
+            + interrupt::typelevel::Binding<T::ErrorInterrupt, ErrorInterruptHandler<T>>
+            + 'd,
         tx_dma: impl Peripheral<P = TXDMA> + 'd,
         rx_dma: impl Peripheral<P = RXDMA> + 'd,
         freq: Hertz,
@@ -98,6 +102,9 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             reg.set_pe(true);
         });
 
+        unsafe { T::EventInterrupt::enable() };
+        unsafe { T::ErrorInterrupt::enable() };
+
         Self {
             phantom: PhantomData,
             tx_dma,
@@ -105,40 +112,58 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         }
     }
 
-    fn check_and_clear_error_flags(&self) -> Result<i2c::regs::Sr1, Error> {
+    fn check_and_clear_error_flags() -> Result<i2c::regs::Sr1, Error> {
         // Note that flags should only be cleared once they have been registered. If flags are
         // cleared otherwise, there may be an inherent race condition and flags may be missed.
         let sr1 = T::regs().sr1().read();
 
         if sr1.timeout() {
-            T::regs().sr1().modify(|reg| reg.set_timeout(false));
+            T::regs().sr1().write(|reg| {
+                reg.0 = !0;
+                reg.set_timeout(false);
+            });
             return Err(Error::Timeout);
         }
 
         if sr1.pecerr() {
-            T::regs().sr1().modify(|reg| reg.set_pecerr(false));
+            T::regs().sr1().write(|reg| {
+                reg.0 = !0;
+                reg.set_pecerr(false);
+            });
             return Err(Error::Crc);
         }
 
         if sr1.ovr() {
-            T::regs().sr1().modify(|reg| reg.set_ovr(false));
+            T::regs().sr1().write(|reg| {
+                reg.0 = !0;
+                reg.set_ovr(false);
+            });
             return Err(Error::Overrun);
         }
 
         if sr1.af() {
-            T::regs().sr1().modify(|reg| reg.set_af(false));
+            T::regs().sr1().write(|reg| {
+                reg.0 = !0;
+                reg.set_af(false);
+            });
             return Err(Error::Nack);
         }
 
         if sr1.arlo() {
-            T::regs().sr1().modify(|reg| reg.set_arlo(false));
+            T::regs().sr1().write(|reg| {
+                reg.0 = !0;
+                reg.set_arlo(false);
+            });
             return Err(Error::Arbitration);
         }
 
         // The errata indicates that BERR may be incorrectly detected. It recommends ignoring and
         // clearing the BERR bit instead.
         if sr1.berr() {
-            T::regs().sr1().modify(|reg| reg.set_berr(false));
+            T::regs().sr1().write(|reg| {
+                reg.0 = !0;
+                reg.set_berr(false);
+            });
         }
 
         Ok(sr1)
@@ -157,13 +182,13 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         });
 
         // Wait until START condition was generated
-        while !self.check_and_clear_error_flags()?.start() {
+        while !Self::check_and_clear_error_flags()?.start() {
             check_timeout()?;
         }
 
         // Also wait until signalled we're master and everything is waiting for us
         while {
-            self.check_and_clear_error_flags()?;
+            Self::check_and_clear_error_flags()?;
 
             let sr2 = T::regs().sr2().read();
             !sr2.msl() && !sr2.busy()
@@ -177,7 +202,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         // Wait until address was sent
         // Wait for the address to be acknowledged
         // Check for any I2C errors. If a NACK occurs, the ADDR bit will never be set.
-        while !self.check_and_clear_error_flags()?.addr() {
+        while !Self::check_and_clear_error_flags()?.addr() {
             check_timeout()?;
         }
 
@@ -197,7 +222,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         // Wait until we're ready for sending
         while {
             // Check for any I2C errors. If a NACK occurs, the ADDR bit will never be set.
-            !self.check_and_clear_error_flags()?.txe()
+            !Self::check_and_clear_error_flags()?.txe()
         } {
             check_timeout()?;
         }
@@ -208,7 +233,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         // Wait until byte is transferred
         while {
             // Check for any potential error conditions.
-            !self.check_and_clear_error_flags()?.btf()
+            !Self::check_and_clear_error_flags()?.btf()
         } {
             check_timeout()?;
         }
@@ -219,7 +244,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
     fn recv_byte(&self, check_timeout: impl Fn() -> Result<(), Error>) -> Result<u8, Error> {
         while {
             // Check for any potential error conditions.
-            self.check_and_clear_error_flags()?;
+            Self::check_and_clear_error_flags()?;
 
             !T::regs().sr1().read().rxne()
         } {
@@ -244,7 +269,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             });
 
             // Wait until START condition was generated
-            while !self.check_and_clear_error_flags()?.start() {
+            while !Self::check_and_clear_error_flags()?.start() {
                 check_timeout()?;
             }
 
@@ -261,7 +286,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
 
             // Wait until address was sent
             // Wait for the address to be acknowledged
-            while !self.check_and_clear_error_flags()?.addr() {
+            while !Self::check_and_clear_error_flags()?.addr() {
                 check_timeout()?;
             }
 
@@ -336,6 +361,322 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
     pub fn blocking_write_read(&mut self, addr: u8, write: &[u8], read: &mut [u8]) -> Result<(), Error> {
         self.blocking_write_read_timeout(addr, write, read, || Ok(()))
     }
+
+    // Async
+
+    #[inline] // pretty sure this should always be inlined
+    fn enable_interrupts() -> () {
+        T::regs().cr2().modify(|w| {
+            w.set_iterren(true);
+            w.set_itevten(true);
+        });
+    }
+
+    pub async fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Error>
+    where
+        TXDMA: crate::i2c::TxDma<T>,
+    {
+        let dma_transfer = unsafe {
+            let regs = T::regs();
+            regs.cr2().modify(|w| {
+                // DMA mode can be enabled for transmission by setting the DMAEN bit in the I2C_CR2 register.
+                w.set_dmaen(true);
+                w.set_itbufen(false);
+            });
+            // Set the I2C_DR register address in the DMA_SxPAR register. The data will be moved to this address from the memory after each TxE event.
+            let dst = regs.dr().as_ptr() as *mut u8;
+
+            let ch = &mut self.tx_dma;
+            let request = ch.request();
+            Transfer::new_write(ch, request, write, dst, Default::default())
+        };
+
+        let on_drop = OnDrop::new(|| {
+            let regs = T::regs();
+            regs.cr2().modify(|w| {
+                w.set_dmaen(false);
+                w.set_iterren(false);
+                w.set_itevten(false);
+            })
+        });
+
+        Self::enable_interrupts();
+
+        // Send a START condition
+        T::regs().cr1().modify(|reg| {
+            reg.set_start(true);
+        });
+
+        let state = T::state();
+
+        // Wait until START condition was generated
+        poll_fn(|cx| {
+            state.waker.register(cx.waker());
+
+            match Self::check_and_clear_error_flags() {
+                Err(e) => Poll::Ready(Err(e)),
+                Ok(sr1) => {
+                    if sr1.start() {
+                        Poll::Ready(Ok(()))
+                    } else {
+                        Poll::Pending
+                    }
+                }
+            }
+        })
+        .await?;
+
+        // Also wait until signalled we're master and everything is waiting for us
+        Self::enable_interrupts();
+        poll_fn(|cx| {
+            state.waker.register(cx.waker());
+
+            match Self::check_and_clear_error_flags() {
+                Err(e) => Poll::Ready(Err(e)),
+                Ok(_) => {
+                    let sr2 = T::regs().sr2().read();
+                    if !sr2.msl() && !sr2.busy() {
+                        Poll::Pending
+                    } else {
+                        Poll::Ready(Ok(()))
+                    }
+                }
+            }
+        })
+        .await?;
+
+        // Set up current address, we're trying to talk to
+        T::regs().dr().write(|reg| reg.set_dr(address << 1));
+        Self::enable_interrupts();
+
+        poll_fn(|cx| {
+            state.waker.register(cx.waker());
+            match Self::check_and_clear_error_flags() {
+                Err(e) => Poll::Ready(Err(e)),
+                Ok(sr1) => {
+                    if sr1.addr() {
+                        // Clear the ADDR condition by reading SR2.
+                        T::regs().sr2().read();
+                        Poll::Ready(Ok(()))
+                    } else {
+                        Poll::Pending
+                    }
+                }
+            }
+        })
+        .await?;
+
+        Self::enable_interrupts();
+        let poll_error = poll_fn(|cx| {
+            state.waker.register(cx.waker());
+
+            match Self::check_and_clear_error_flags() {
+                // Unclear why the Err turbofish is necessary here? The compiler didn’t require it in the other
+                // identical poll_fn check_and_clear matches.
+                Err(e) => Poll::Ready(Err::<T, Error>(e)),
+                Ok(_) => Poll::Pending,
+            }
+        });
+
+        // Wait for either the DMA transfer to successfully finish, or an I2C error to occur.
+        match select(dma_transfer, poll_error).await {
+            Either::Second(Err(e)) => Err(e),
+            _ => Ok(()),
+        }?;
+
+        // The I2C transfer itself will take longer than the DMA transfer, so wait for that to finish too.
+
+        // 18.3.8 “Master transmitter: In the interrupt routine after the EOT interrupt, disable DMA
+        // requests then wait for a BTF event before programming the Stop condition.”
+
+        // TODO: If this has to be done “in the interrupt routine after the EOT interrupt”, where to put it?
+        T::regs().cr2().modify(|w| {
+            w.set_dmaen(false);
+        });
+
+        Self::enable_interrupts();
+        poll_fn(|cx| {
+            state.waker.register(cx.waker());
+
+            match Self::check_and_clear_error_flags() {
+                Err(e) => Poll::Ready(Err(e)),
+                Ok(sr1) => {
+                    if sr1.btf() {
+                        T::regs().cr1().modify(|w| {
+                            w.set_stop(true);
+                        });
+                        Poll::Ready(Ok(()))
+                    } else {
+                        Poll::Pending
+                    }
+                }
+            }
+        })
+        .await?;
+        // Wait for STOP condition to transmit.
+        Self::enable_interrupts();
+        poll_fn(|cx| {
+            state.waker.register(cx.waker());
+
+            if T::regs().cr1().read().stop() {
+                Poll::Pending
+            } else {
+                Poll::Ready(Ok(()))
+            }
+        })
+        .await?;
+
+        drop(on_drop);
+
+        // Fallthrough is success
+        Ok(())
+    }
+
+    pub async fn read(&mut self, address: u8, buffer: &mut [u8]) -> Result<(), Error>
+    where
+        RXDMA: crate::i2c::RxDma<T>,
+    {
+        let state = T::state();
+        let buffer_len = buffer.len();
+
+        let dma_transfer = unsafe {
+            let regs = T::regs();
+            regs.cr2().modify(|w| {
+                // DMA mode can be enabled for transmission by setting the DMAEN bit in the I2C_CR2 register.
+                w.set_itbufen(false);
+                w.set_dmaen(true);
+            });
+            // Set the I2C_DR register address in the DMA_SxPAR register. The data will be moved to this address from the memory after each TxE event.
+            let src = regs.dr().as_ptr() as *mut u8;
+
+            let ch = &mut self.rx_dma;
+            let request = ch.request();
+            Transfer::new_read(ch, request, src, buffer, Default::default())
+        };
+
+        let on_drop = OnDrop::new(|| {
+            let regs = T::regs();
+            regs.cr2().modify(|w| {
+                w.set_dmaen(false);
+                w.set_iterren(false);
+                w.set_itevten(false);
+            })
+        });
+
+        Self::enable_interrupts();
+
+        // Send a START condition and set ACK bit
+        T::regs().cr1().modify(|reg| {
+            reg.set_start(true);
+            reg.set_ack(true);
+        });
+
+        // Wait until START condition was generated
+        poll_fn(|cx| {
+            state.waker.register(cx.waker());
+
+            match Self::check_and_clear_error_flags() {
+                Err(e) => Poll::Ready(Err(e)),
+                Ok(sr1) => {
+                    if sr1.start() {
+                        Poll::Ready(Ok(()))
+                    } else {
+                        Poll::Pending
+                    }
+                }
+            }
+        })
+        .await?;
+
+        // Also wait until signalled we're master and everything is waiting for us
+        Self::enable_interrupts();
+        poll_fn(|cx| {
+            state.waker.register(cx.waker());
+
+            // blocking read didn’t have a check_and_clear call here, but blocking write did so
+            // I’m adding it here in case that was an oversight.
+            match Self::check_and_clear_error_flags() {
+                Err(e) => Poll::Ready(Err(e)),
+                Ok(_) => {
+                    let sr2 = T::regs().sr2().read();
+                    if !sr2.msl() && !sr2.busy() {
+                        Poll::Pending
+                    } else {
+                        Poll::Ready(Ok(()))
+                    }
+                }
+            }
+        })
+        .await?;
+
+        // Set up current address, we're trying to talk to
+        T::regs().dr().write(|reg| reg.set_dr((address << 1) + 1));
+
+        // Wait for the address to be acknowledged
+
+        Self::enable_interrupts();
+        poll_fn(|cx| {
+            state.waker.register(cx.waker());
+
+            match Self::check_and_clear_error_flags() {
+                Err(e) => Poll::Ready(Err(e)),
+                Ok(sr1) => {
+                    if sr1.addr() {
+                        // 18.3.8: When a single byte must be received: the NACK must be programmed during EV6
+                        // event, i.e. program ACK=0 when ADDR=1, before clearing ADDR flag. Then the
+                        // user can program the STOP condition either after clearing ADDR flag, or in the
+                        // DMA Transfer Complete interrupt routine.
+                        if buffer_len == 1 {
+                            T::regs().cr1().modify(|w| {
+                                w.set_ack(false);
+                            });
+                        }
+                        Poll::Ready(Ok(()))
+                    } else {
+                        Poll::Pending
+                    }
+                }
+            }
+        })
+        .await?;
+
+        // Clear condition by reading SR2
+        T::regs().sr2().read();
+
+        // Wait for bytes to be received, or an error to occur.
+        Self::enable_interrupts();
+        let poll_error = poll_fn(|cx| {
+            state.waker.register(cx.waker());
+
+            match Self::check_and_clear_error_flags() {
+                Err(e) => Poll::Ready(Err::<T, Error>(e)),
+                _ => Poll::Pending,
+            }
+        });
+
+        match select(dma_transfer, poll_error).await {
+            Either::Second(Err(e)) => Err(e),
+            _ => Ok(()),
+        };
+
+        // v1 blocking waits for STOP to be written, the manual says to write the STOP bit yourself.
+        // what to do…
+        // Wait for the STOP to be sent.
+        // while T::regs().cr1().read().stop() {
+        //     check_timeout()?;
+        // }
+
+        // Fallthrough is success
+        Ok(())
+    }
+
+    pub async fn write_read(&mut self, _address: u8, _write: &[u8], _read: &mut [u8]) -> Result<(), Error>
+    where
+        RXDMA: crate::i2c::RxDma<T>,
+        TXDMA: crate::i2c::TxDma<T>,
+    {
+        todo!()
+    }
 }
 
 impl<'d, T: Instance, TXDMA, RXDMA> Drop for I2c<'d, T, TXDMA, RXDMA> {
@@ -344,77 +685,6 @@ impl<'d, T: Instance, TXDMA, RXDMA> Drop for I2c<'d, T, TXDMA, RXDMA> {
     }
 }
 
-impl<'d, T: Instance> embedded_hal_02::blocking::i2c::Read for I2c<'d, T> {
-    type Error = Error;
-
-    fn read(&mut self, addr: u8, read: &mut [u8]) -> Result<(), Self::Error> {
-        self.blocking_read(addr, read)
-    }
-}
-
-impl<'d, T: Instance> embedded_hal_02::blocking::i2c::Write for I2c<'d, T> {
-    type Error = Error;
-
-    fn write(&mut self, addr: u8, write: &[u8]) -> Result<(), Self::Error> {
-        self.blocking_write(addr, write)
-    }
-}
-
-impl<'d, T: Instance> embedded_hal_02::blocking::i2c::WriteRead for I2c<'d, T> {
-    type Error = Error;
-
-    fn write_read(&mut self, addr: u8, write: &[u8], read: &mut [u8]) -> Result<(), Self::Error> {
-        self.blocking_write_read(addr, write, read)
-    }
-}
-
-#[cfg(feature = "unstable-traits")]
-mod eh1 {
-    use super::*;
-
-    impl embedded_hal_1::i2c::Error for Error {
-        fn kind(&self) -> embedded_hal_1::i2c::ErrorKind {
-            match *self {
-                Self::Bus => embedded_hal_1::i2c::ErrorKind::Bus,
-                Self::Arbitration => embedded_hal_1::i2c::ErrorKind::ArbitrationLoss,
-                Self::Nack => {
-                    embedded_hal_1::i2c::ErrorKind::NoAcknowledge(embedded_hal_1::i2c::NoAcknowledgeSource::Unknown)
-                }
-                Self::Timeout => embedded_hal_1::i2c::ErrorKind::Other,
-                Self::Crc => embedded_hal_1::i2c::ErrorKind::Other,
-                Self::Overrun => embedded_hal_1::i2c::ErrorKind::Overrun,
-                Self::ZeroLengthTransfer => embedded_hal_1::i2c::ErrorKind::Other,
-            }
-        }
-    }
-
-    impl<'d, T: Instance> embedded_hal_1::i2c::ErrorType for I2c<'d, T> {
-        type Error = Error;
-    }
-
-    impl<'d, T: Instance> embedded_hal_1::i2c::I2c for I2c<'d, T> {
-        fn read(&mut self, address: u8, read: &mut [u8]) -> Result<(), Self::Error> {
-            self.blocking_read(address, read)
-        }
-
-        fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Self::Error> {
-            self.blocking_write(address, write)
-        }
-
-        fn write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Self::Error> {
-            self.blocking_write_read(address, write, read)
-        }
-
-        fn transaction(
-            &mut self,
-            _address: u8,
-            _operations: &mut [embedded_hal_1::i2c::Operation<'_>],
-        ) -> Result<(), Self::Error> {
-            todo!();
-        }
-    }
-}
-
 enum Mode {
     Fast,
     Standard,

embassy-stm32/src/i2c/v2.rs

@@ -1,48 +1,51 @@
 use core::cmp;
-#[cfg(feature = "time")]
 use core::future::poll_fn;
-use core::marker::PhantomData;
-#[cfg(feature = "time")]
 use core::task::Poll;
 
 use embassy_embedded_hal::SetConfig;
-#[cfg(feature = "time")]
 use embassy_hal_internal::drop::OnDrop;
 use embassy_hal_internal::{into_ref, PeripheralRef};
-use embassy_sync::waitqueue::AtomicWaker;
 #[cfg(feature = "time")]
 use embassy_time::{Duration, Instant};
 
-use crate::dma::NoDma;
-#[cfg(feature = "time")]
-use crate::dma::Transfer;
+use super::*;
+use crate::dma::{NoDma, Transfer};
 use crate::gpio::sealed::AFType;
 use crate::gpio::Pull;
-use crate::i2c::{Error, Instance, SclPin, SdaPin};
 use crate::interrupt::typelevel::Interrupt;
 use crate::pac::i2c;
 use crate::time::Hertz;
 use crate::{interrupt, Peripheral};
 
-/// Interrupt handler.
-pub struct InterruptHandler<T: Instance> {
-    _phantom: PhantomData<T>,
+#[cfg(feature = "time")]
+fn timeout_fn(timeout: Duration) -> impl Fn() -> Result<(), Error> {
+    let deadline = Instant::now() + timeout;
+    move || {
+        if Instant::now() > deadline {
+            Err(Error::Timeout)
+        } else {
+            Ok(())
+        }
+    }
 }
 
-impl<T: Instance> interrupt::typelevel::Handler<T::Interrupt> for InterruptHandler<T> {
-    unsafe fn on_interrupt() {
-        let regs = T::regs();
-        let isr = regs.isr().read();
+#[cfg(not(feature = "time"))]
+pub fn no_timeout_fn() -> impl Fn() -> Result<(), Error> {
+    move || Ok(())
+}
 
-        if isr.tcr() || isr.tc() {
-            T::state().waker.wake();
-        }
-        // The flag can only be cleared by writting to nbytes, we won't do that here, so disable
-        // the interrupt
-        critical_section::with(|_| {
-            regs.cr1().modify(|w| w.set_tcie(false));
-        });
+pub unsafe fn on_interrupt<T: Instance>() {
+    let regs = T::regs();
+    let isr = regs.isr().read();
+
+    if isr.tcr() || isr.tc() {
+        T::state().waker.wake();
     }
+    // The flag can only be cleared by writting to nbytes, we won't do that here, so disable
+    // the interrupt
+    critical_section::with(|_| {
+        regs.cr1().modify(|w| w.set_tcie(false));
+    });
 }
 
 #[non_exhaustive]
@@ -65,18 +68,6 @@ impl Default for Config {
     }
 }
 
-pub struct State {
-    waker: AtomicWaker,
-}
-
-impl State {
-    pub(crate) const fn new() -> Self {
-        Self {
-            waker: AtomicWaker::new(),
-        }
-    }
-}
-
 pub struct I2c<'d, T: Instance, TXDMA = NoDma, RXDMA = NoDma> {
     _peri: PeripheralRef<'d, T>,
     #[allow(dead_code)]
@@ -92,7 +83,9 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         peri: impl Peripheral<P = T> + 'd,
         scl: impl Peripheral<P = impl SclPin<T>> + 'd,
         sda: impl Peripheral<P = impl SdaPin<T>> + 'd,
-        _irq: impl interrupt::typelevel::Binding<T::Interrupt, InterruptHandler<T>> + 'd,
+        _irq: impl interrupt::typelevel::Binding<T::EventInterrupt, EventInterruptHandler<T>>
+            + interrupt::typelevel::Binding<T::ErrorInterrupt, ErrorInterruptHandler<T>>
+            + 'd,
         tx_dma: impl Peripheral<P = TXDMA> + 'd,
         rx_dma: impl Peripheral<P = RXDMA> + 'd,
         freq: Hertz,
@@ -138,8 +131,8 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             reg.set_pe(true);
         });
 
-        T::Interrupt::unpend();
-        unsafe { T::Interrupt::enable() };
+        unsafe { T::EventInterrupt::enable() };
+        unsafe { T::ErrorInterrupt::enable() };
 
         Self {
             _peri: peri,
@@ -260,21 +253,12 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
     }
 
     fn flush_txdr(&self) {
-        //if $i2c.isr.read().txis().bit_is_set() {
-        //$i2c.txdr.write(|w| w.txdata().bits(0));
-        //}
-
         if T::regs().isr().read().txis() {
             T::regs().txdr().write(|w| w.set_txdata(0));
         }
         if !T::regs().isr().read().txe() {
             T::regs().isr().modify(|w| w.set_txe(true))
         }
-
-        // If TXDR is not flagged as empty, write 1 to flush it
-        //if $i2c.isr.read().txe().is_not_empty() {
-        //$i2c.isr.write(|w| w.txe().set_bit());
-        //}
     }
 
     fn wait_txe(&self, check_timeout: impl Fn() -> Result<(), Error>) -> Result<(), Error> {
@@ -437,7 +421,6 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         result
     }
 
-    #[cfg(feature = "time")]
     async fn write_dma_internal(
         &mut self,
         address: u8,
@@ -528,7 +511,6 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         Ok(())
     }
 
-    #[cfg(feature = "time")]
     async fn read_dma_internal(
         &mut self,
         address: u8,
@@ -610,42 +592,38 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
 
     // =========================
     //  Async public API
-
     #[cfg(feature = "time")]
     pub async fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Error>
-    where
-        TXDMA: crate::i2c::TxDma<T>,
-    {
-        self.write_timeout(address, write, self.timeout).await
-    }
-
-    #[cfg(feature = "time")]
-    pub async fn write_timeout(&mut self, address: u8, write: &[u8], timeout: Duration) -> Result<(), Error>
     where
         TXDMA: crate::i2c::TxDma<T>,
     {
         if write.is_empty() {
-            self.write_internal(address, write, true, timeout_fn(timeout))
+            self.write_internal(address, write, true, timeout_fn(self.timeout))
         } else {
             embassy_time::with_timeout(
-                timeout,
-                self.write_dma_internal(address, write, true, true, timeout_fn(timeout)),
+                self.timeout,
+                self.write_dma_internal(address, write, true, true, timeout_fn(self.timeout)),
             )
             .await
             .unwrap_or(Err(Error::Timeout))
         }
     }
 
-    #[cfg(feature = "time")]
-    pub async fn write_vectored(&mut self, address: u8, write: &[&[u8]]) -> Result<(), Error>
+    #[cfg(not(feature = "time"))]
+    pub async fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Error>
     where
         TXDMA: crate::i2c::TxDma<T>,
     {
-        self.write_vectored_timeout(address, write, self.timeout).await
+        if write.is_empty() {
+            self.write_internal(address, write, true, no_timeout_fn())
+        } else {
+            self.write_dma_internal(address, write, true, true, no_timeout_fn())
+                .await
+        }
     }
 
     #[cfg(feature = "time")]
-    pub async fn write_vectored_timeout(&mut self, address: u8, write: &[&[u8]], timeout: Duration) -> Result<(), Error>
+    pub async fn write_vectored(&mut self, address: u8, write: &[&[u8]]) -> Result<(), Error>
     where
         TXDMA: crate::i2c::TxDma<T>,
     {
@@ -661,8 +639,8 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             let is_last = next.is_none();
 
             embassy_time::with_timeout(
-                timeout,
-                self.write_dma_internal(address, c, first, is_last, timeout_fn(timeout)),
+                self.timeout,
+                self.write_dma_internal(address, c, first, is_last, timeout_fn(self.timeout)),
             )
             .await
             .unwrap_or(Err(Error::Timeout))?;
@@ -672,66 +650,79 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         Ok(())
     }
 
+    #[cfg(not(feature = "time"))]
+    pub async fn write_vectored(&mut self, address: u8, write: &[&[u8]]) -> Result<(), Error>
+    where
+        TXDMA: crate::i2c::TxDma<T>,
+    {
+        if write.is_empty() {
+            return Err(Error::ZeroLengthTransfer);
+        }
+        let mut iter = write.iter();
+
+        let mut first = true;
+        let mut current = iter.next();
+        while let Some(c) = current {
+            let next = iter.next();
+            let is_last = next.is_none();
+
+            self.write_dma_internal(address, c, first, is_last, no_timeout_fn())
+                .await?;
+            first = false;
+            current = next;
+        }
+        Ok(())
+    }
+
     #[cfg(feature = "time")]
     pub async fn read(&mut self, address: u8, buffer: &mut [u8]) -> Result<(), Error>
     where
         RXDMA: crate::i2c::RxDma<T>,
     {
-        self.read_timeout(address, buffer, self.timeout).await
+        if buffer.is_empty() {
+            self.read_internal(address, buffer, false, timeout_fn(self.timeout))
+        } else {
+            embassy_time::with_timeout(
+                self.timeout,
+                self.read_dma_internal(address, buffer, false, timeout_fn(self.timeout)),
+            )
+            .await
+            .unwrap_or(Err(Error::Timeout))
+        }
     }
 
-    #[cfg(feature = "time")]
-    pub async fn read_timeout(&mut self, address: u8, buffer: &mut [u8], timeout: Duration) -> Result<(), Error>
+    #[cfg(not(feature = "time"))]
+    pub async fn read(&mut self, address: u8, buffer: &mut [u8]) -> Result<(), Error>
     where
         RXDMA: crate::i2c::RxDma<T>,
     {
         if buffer.is_empty() {
-            self.read_internal(address, buffer, false, timeout_fn(timeout))
+            self.read_internal(address, buffer, false, no_timeout_fn())
         } else {
-            embassy_time::with_timeout(
-                timeout,
-                self.read_dma_internal(address, buffer, false, timeout_fn(timeout)),
-            )
-            .await
-            .unwrap_or(Err(Error::Timeout))
+            self.read_dma_internal(address, buffer, false, no_timeout_fn()).await
         }
     }
 
     #[cfg(feature = "time")]
     pub async fn write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Error>
-    where
-        TXDMA: super::TxDma<T>,
-        RXDMA: super::RxDma<T>,
-    {
-        self.write_read_timeout(address, write, read, self.timeout).await
-    }
-
-    #[cfg(feature = "time")]
-    pub async fn write_read_timeout(
-        &mut self,
-        address: u8,
-        write: &[u8],
-        read: &mut [u8],
-        timeout: Duration,
-    ) -> Result<(), Error>
     where
         TXDMA: super::TxDma<T>,
         RXDMA: super::RxDma<T>,
     {
         let start_instant = Instant::now();
-        let check_timeout = timeout_fn(timeout);
+        let check_timeout = timeout_fn(self.timeout);
         if write.is_empty() {
             self.write_internal(address, write, false, &check_timeout)?;
         } else {
             embassy_time::with_timeout(
-                timeout,
+                self.timeout,
                 self.write_dma_internal(address, write, true, true, &check_timeout),
             )
             .await
             .unwrap_or(Err(Error::Timeout))?;
         }
 
-        let time_left_until_timeout = timeout - Instant::now().duration_since(start_instant);
+        let time_left_until_timeout = self.timeout - Instant::now().duration_since(start_instant);
 
         if read.is_empty() {
             self.read_internal(address, read, true, &check_timeout)?;
@@ -747,6 +738,28 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         Ok(())
     }
 
+    #[cfg(not(feature = "time"))]
+    pub async fn write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Error>
+    where
+        TXDMA: super::TxDma<T>,
+        RXDMA: super::RxDma<T>,
+    {
+        let no_timeout = no_timeout_fn();
+        if write.is_empty() {
+            self.write_internal(address, write, false, &no_timeout)?;
+        } else {
+            self.write_dma_internal(address, write, true, true, &no_timeout).await?;
+        }
+
+        if read.is_empty() {
+            self.read_internal(address, read, true, &no_timeout)?;
+        } else {
+            self.read_dma_internal(address, read, true, &no_timeout).await?;
+        }
+
+        Ok(())
+    }
+
     // =========================
     //  Blocking public API
 
@@ -955,35 +968,6 @@ impl<'d, T: Instance, TXDMA, RXDMA> Drop for I2c<'d, T, TXDMA, RXDMA> {
     }
 }
 
-#[cfg(feature = "time")]
-mod eh02 {
-    use super::*;
-
-    impl<'d, T: Instance> embedded_hal_02::blocking::i2c::Read for I2c<'d, T> {
-        type Error = Error;
-
-        fn read(&mut self, address: u8, buffer: &mut [u8]) -> Result<(), Self::Error> {
-            self.blocking_read(address, buffer)
-        }
-    }
-
-    impl<'d, T: Instance> embedded_hal_02::blocking::i2c::Write for I2c<'d, T> {
-        type Error = Error;
-
-        fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Self::Error> {
-            self.blocking_write(address, write)
-        }
-    }
-
-    impl<'d, T: Instance> embedded_hal_02::blocking::i2c::WriteRead for I2c<'d, T> {
-        type Error = Error;
-
-        fn write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Self::Error> {
-            self.blocking_write_read(address, write, read)
-        }
-    }
-}
-
 /// I2C Stop Configuration
 ///
 /// Peripheral options for generating the STOP condition
@@ -1108,83 +1092,6 @@ impl Timings {
     }
 }
 
-#[cfg(feature = "unstable-traits")]
-mod eh1 {
-    use super::*;
-
-    impl embedded_hal_1::i2c::Error for Error {
-        fn kind(&self) -> embedded_hal_1::i2c::ErrorKind {
-            match *self {
-                Self::Bus => embedded_hal_1::i2c::ErrorKind::Bus,
-                Self::Arbitration => embedded_hal_1::i2c::ErrorKind::ArbitrationLoss,
-                Self::Nack => {
-                    embedded_hal_1::i2c::ErrorKind::NoAcknowledge(embedded_hal_1::i2c::NoAcknowledgeSource::Unknown)
-                }
-                Self::Timeout => embedded_hal_1::i2c::ErrorKind::Other,
-                Self::Crc => embedded_hal_1::i2c::ErrorKind::Other,
-                Self::Overrun => embedded_hal_1::i2c::ErrorKind::Overrun,
-                Self::ZeroLengthTransfer => embedded_hal_1::i2c::ErrorKind::Other,
-            }
-        }
-    }
-
-    impl<'d, T: Instance, TXDMA, RXDMA> embedded_hal_1::i2c::ErrorType for I2c<'d, T, TXDMA, RXDMA> {
-        type Error = Error;
-    }
-
-    impl<'d, T: Instance> embedded_hal_1::i2c::I2c for I2c<'d, T, NoDma, NoDma> {
-        fn read(&mut self, address: u8, read: &mut [u8]) -> Result<(), Self::Error> {
-            self.blocking_read(address, read)
-        }
-
-        fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Self::Error> {
-            self.blocking_write(address, write)
-        }
-
-        fn write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Self::Error> {
-            self.blocking_write_read(address, write, read)
-        }
-
-        fn transaction(
-            &mut self,
-            _address: u8,
-            _operations: &mut [embedded_hal_1::i2c::Operation<'_>],
-        ) -> Result<(), Self::Error> {
-            todo!();
-        }
-    }
-}
-
-#[cfg(all(feature = "unstable-traits", feature = "nightly", feature = "time"))]
-mod eha {
-    use super::super::{RxDma, TxDma};
-    use super::*;
-
-    impl<'d, T: Instance, TXDMA: TxDma<T>, RXDMA: RxDma<T>> embedded_hal_async::i2c::I2c for I2c<'d, T, TXDMA, RXDMA> {
-        async fn read(&mut self, address: u8, read: &mut [u8]) -> Result<(), Self::Error> {
-            self.read(address, read).await
-        }
-
-        async fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Self::Error> {
-            self.write(address, write).await
-        }
-
-        async fn write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Self::Error> {
-            self.write_read(address, write, read).await
-        }
-
-        async fn transaction(
-            &mut self,
-            address: u8,
-            operations: &mut [embedded_hal_1::i2c::Operation<'_>],
-        ) -> Result<(), Self::Error> {
-            let _ = address;
-            let _ = operations;
-            todo!()
-        }
-    }
-}
-
 impl<'d, T: Instance> SetConfig for I2c<'d, T> {
     type Config = Hertz;
     type ConfigError = ();
@@ -1201,15 +1108,3 @@ impl<'d, T: Instance> SetConfig for I2c<'d, T> {
         Ok(())
     }
 }
-
-#[cfg(feature = "time")]
-fn timeout_fn(timeout: Duration) -> impl Fn() -> Result<(), Error> {
-    let deadline = Instant::now() + timeout;
-    move || {
-        if Instant::now() > deadline {
-            Err(Error::Timeout)
-        } else {
-            Ok(())
-        }
-    }
-}

examples/stm32f4/src/bin/i2c.rs

@@ -14,7 +14,8 @@ const ADDRESS: u8 = 0x5F;
 const WHOAMI: u8 = 0x0F;
 
 bind_interrupts!(struct Irqs {
-    I2C2_EV => i2c::InterruptHandler<peripherals::I2C2>;
+    I2C2_EV => i2c::EventInterruptHandler<peripherals::I2C2>;
+    I2C2_ER => i2c::ErrorInterruptHandler<peripherals::I2C2>;
 });
 
 #[embassy_executor::main]

examples/stm32h5/src/bin/i2c.rs

@@ -13,7 +13,8 @@ const ADDRESS: u8 = 0x5F;
 const WHOAMI: u8 = 0x0F;
 
 bind_interrupts!(struct Irqs {
-    I2C2_EV => i2c::InterruptHandler<peripherals::I2C2>;
+    I2C2_EV => i2c::EventInterruptHandler<peripherals::I2C2>;
+    I2C2_ER => i2c::ErrorInterruptHandler<peripherals::I2C2>;
 });
 
 #[embassy_executor::main]

examples/stm32h7/src/bin/camera.rs

@@ -19,7 +19,8 @@ const HEIGHT: usize = 100;
 static mut FRAME: [u32; WIDTH * HEIGHT / 2] = [0u32; WIDTH * HEIGHT / 2];
 
 bind_interrupts!(struct Irqs {
-    I2C1_EV => i2c::InterruptHandler<peripherals::I2C1>;
+    I2C1_EV => i2c::EventInterruptHandler<peripherals::I2C1>;
+    I2C1_ER => i2c::ErrorInterruptHandler<peripherals::I2C1>;
     DCMI => dcmi::InterruptHandler<peripherals::DCMI>;
 });
 

examples/stm32h7/src/bin/i2c.rs

@@ -13,7 +13,8 @@ const ADDRESS: u8 = 0x5F;
 const WHOAMI: u8 = 0x0F;
 
 bind_interrupts!(struct Irqs {
-    I2C2_EV => i2c::InterruptHandler<peripherals::I2C2>;
+    I2C2_EV => i2c::EventInterruptHandler<peripherals::I2C2>;
+    I2C2_ER => i2c::ErrorInterruptHandler<peripherals::I2C2>;
 });
 
 #[embassy_executor::main]

examples/stm32l4/src/bin/i2c.rs

@@ -14,7 +14,8 @@ const ADDRESS: u8 = 0x5F;
 const WHOAMI: u8 = 0x0F;
 
 bind_interrupts!(struct Irqs {
-    I2C2_EV => i2c::InterruptHandler<peripherals::I2C2>;
+    I2C2_EV => i2c::EventInterruptHandler<peripherals::I2C2>;
+    I2C2_ER => i2c::ErrorInterruptHandler<peripherals::I2C2>;
 });
 
 #[embassy_executor::main]

examples/stm32l4/src/bin/i2c_blocking_async.rs

@@ -16,7 +16,8 @@ const ADDRESS: u8 = 0x5F;
 const WHOAMI: u8 = 0x0F;
 
 bind_interrupts!(struct Irqs {
-    I2C2_EV => i2c::InterruptHandler<peripherals::I2C2>;
+    I2C2_EV => i2c::EventInterruptHandler<peripherals::I2C2>;
+    I2C2_ER => i2c::ErrorInterruptHandler<peripherals::I2C2>;
 });
 
 #[embassy_executor::main]

examples/stm32l4/src/bin/i2c_dma.rs

@@ -13,7 +13,8 @@ const ADDRESS: u8 = 0x5F;
 const WHOAMI: u8 = 0x0F;
 
 bind_interrupts!(struct Irqs {
-    I2C2_EV => i2c::InterruptHandler<peripherals::I2C2>;
+    I2C2_EV => i2c::EventInterruptHandler<peripherals::I2C2>;
+    I2C2_ER => i2c::ErrorInterruptHandler<peripherals::I2C2>;
 });
 
 #[embassy_executor::main]

examples/stm32l4/src/bin/spe_adin1110_http_server.rs

@@ -40,7 +40,8 @@ use static_cell::make_static;
 use {embassy_stm32 as hal, panic_probe as _};
 
 bind_interrupts!(struct Irqs {
-    I2C3_EV => i2c::InterruptHandler<peripherals::I2C3>;
+    I2C3_EV => i2c::EventInterruptHandler<peripherals::I2C3>;
+    I2C3_ER => i2c::ErrorInterruptHandler<peripherals::I2C3>;
     RNG => rng::InterruptHandler<peripherals::RNG>;
 });