Merge pull request #2304 from embassy-rs/stm32-docs

stm32/i2c: remove _timeout public API, share more code between v1/v2.

embassy-stm32/src/i2c/mod.rs

@@ -1,17 +1,23 @@
 #![macro_use]
 
-use core::marker::PhantomData;
-
-use crate::dma::NoDma;
-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;
+use core::future::Future;
+use core::marker::PhantomData;
+
+use embassy_hal_internal::{into_ref, Peripheral, PeripheralRef};
+use embassy_sync::waitqueue::AtomicWaker;
+#[cfg(feature = "time")]
+use embassy_time::{Duration, Instant};
+
+use crate::dma::NoDma;
+use crate::gpio::sealed::AFType;
+use crate::gpio::Pull;
+use crate::interrupt::typelevel::Interrupt;
+use crate::time::Hertz;
+use crate::{interrupt, peripherals};
 
 /// I2C error.
 #[derive(Debug, PartialEq, Eq)]
@@ -33,6 +39,148 @@ pub enum Error {
     ZeroLengthTransfer,
 }
 
+/// I2C config
+#[non_exhaustive]
+#[derive(Copy, Clone)]
+pub struct Config {
+    /// Enable internal pullup on SDA.
+    ///
+    /// Using external pullup resistors is recommended for I2C. If you do
+    /// have external pullups you should not enable this.
+    pub sda_pullup: bool,
+    /// Enable internal pullup on SCL.
+    ///
+    /// Using external pullup resistors is recommended for I2C. If you do
+    /// have external pullups you should not enable this.
+    pub scl_pullup: bool,
+    /// Timeout.
+    #[cfg(feature = "time")]
+    pub timeout: embassy_time::Duration,
+}
+
+impl Default for Config {
+    fn default() -> Self {
+        Self {
+            sda_pullup: false,
+            scl_pullup: false,
+            #[cfg(feature = "time")]
+            timeout: embassy_time::Duration::from_millis(1000),
+        }
+    }
+}
+
+/// I2C driver.
+pub struct I2c<'d, T: Instance, TXDMA = NoDma, RXDMA = NoDma> {
+    _peri: PeripheralRef<'d, T>,
+    #[allow(dead_code)]
+    tx_dma: PeripheralRef<'d, TXDMA>,
+    #[allow(dead_code)]
+    rx_dma: PeripheralRef<'d, RXDMA>,
+    #[cfg(feature = "time")]
+    timeout: Duration,
+}
+
+impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
+    /// Create a new I2C driver.
+    pub fn new(
+        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::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,
+        config: Config,
+    ) -> Self {
+        into_ref!(peri, scl, sda, tx_dma, rx_dma);
+
+        T::enable_and_reset();
+
+        scl.set_as_af_pull(
+            scl.af_num(),
+            AFType::OutputOpenDrain,
+            match config.scl_pullup {
+                true => Pull::Up,
+                false => Pull::None,
+            },
+        );
+        sda.set_as_af_pull(
+            sda.af_num(),
+            AFType::OutputOpenDrain,
+            match config.sda_pullup {
+                true => Pull::Up,
+                false => Pull::None,
+            },
+        );
+
+        unsafe { T::EventInterrupt::enable() };
+        unsafe { T::ErrorInterrupt::enable() };
+
+        let mut this = Self {
+            _peri: peri,
+            tx_dma,
+            rx_dma,
+            #[cfg(feature = "time")]
+            timeout: config.timeout,
+        };
+
+        this.init(freq, config);
+
+        this
+    }
+
+    fn timeout(&self) -> Timeout {
+        Timeout {
+            #[cfg(feature = "time")]
+            deadline: Instant::now() + self.timeout,
+        }
+    }
+}
+
+#[derive(Copy, Clone)]
+struct Timeout {
+    #[cfg(feature = "time")]
+    deadline: Instant,
+}
+
+#[allow(dead_code)]
+impl Timeout {
+    #[cfg(not(feature = "time"))]
+    #[inline]
+    fn check(self) -> Result<(), Error> {
+        Ok(())
+    }
+
+    #[cfg(feature = "time")]
+    #[inline]
+    fn check(self) -> Result<(), Error> {
+        if Instant::now() > self.deadline {
+            Err(Error::Timeout)
+        } else {
+            Ok(())
+        }
+    }
+
+    #[cfg(not(feature = "time"))]
+    #[inline]
+    fn with<R>(self, fut: impl Future<Output = Result<R, Error>>) -> impl Future<Output = Result<R, Error>> {
+        fut
+    }
+
+    #[cfg(feature = "time")]
+    #[inline]
+    fn with<R>(self, fut: impl Future<Output = Result<R, Error>>) -> impl Future<Output = Result<R, Error>> {
+        use futures::FutureExt;
+
+        embassy_futures::select::select(embassy_time::Timer::at(self.deadline), fut).map(|r| match r {
+            embassy_futures::select::Either::First(_) => Err(Error::Timeout),
+            embassy_futures::select::Either::Second(r) => r,
+        })
+    }
+}
+
 pub(crate) mod sealed {
     use super::*;
 

embassy-stm32/src/i2c/v1.rs

@@ -1,20 +1,14 @@
 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 super::*;
-use crate::dma::{NoDma, Transfer};
+use crate::dma::Transfer;
-use crate::gpio::sealed::AFType;
-use crate::gpio::Pull;
-use crate::interrupt::typelevel::Interrupt;
 use crate::pac::i2c;
 use crate::time::Hertz;
-use crate::{interrupt, Peripheral};
 
 pub unsafe fn on_interrupt<T: Instance>() {
     let regs = T::regs();
@@ -30,55 +24,8 @@ pub unsafe fn on_interrupt<T: Instance>() {
     });
 }
 
-#[non_exhaustive]
-#[derive(Copy, Clone, Default)]
-pub struct Config {
-    pub sda_pullup: bool,
-    pub scl_pullup: bool,
-}
-
-pub struct I2c<'d, T: Instance, TXDMA = NoDma, RXDMA = NoDma> {
-    phantom: PhantomData<&'d mut T>,
-    #[allow(dead_code)]
-    tx_dma: PeripheralRef<'d, TXDMA>,
-    #[allow(dead_code)]
-    rx_dma: PeripheralRef<'d, RXDMA>,
-}
-
 impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
-    pub fn new(
+    pub(crate) fn init(&mut self, freq: Hertz, _config: Config) {
-        _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::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,
-        config: Config,
-    ) -> Self {
-        into_ref!(scl, sda, tx_dma, rx_dma);
-
-        T::enable_and_reset();
-
-        scl.set_as_af_pull(
-            scl.af_num(),
-            AFType::OutputOpenDrain,
-            match config.scl_pullup {
-                true => Pull::Up,
-                false => Pull::None,
-            },
-        );
-        sda.set_as_af_pull(
-            sda.af_num(),
-            AFType::OutputOpenDrain,
-            match config.sda_pullup {
-                true => Pull::Up,
-                false => Pull::None,
-            },
-        );
-
         T::regs().cr1().modify(|reg| {
             reg.set_pe(false);
             //reg.set_anfoff(false);
@@ -101,15 +48,6 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         T::regs().cr1().modify(|reg| {
             reg.set_pe(true);
         });
-
-        unsafe { T::EventInterrupt::enable() };
-        unsafe { T::ErrorInterrupt::enable() };
-
-        Self {
-            phantom: PhantomData,
-            tx_dma,
-            rx_dma,
-        }
     }
 
     fn check_and_clear_error_flags() -> Result<i2c::regs::Sr1, Error> {
@@ -169,12 +107,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         Ok(sr1)
     }
 
-    fn write_bytes(
+    fn write_bytes(&mut self, addr: u8, bytes: &[u8], timeout: Timeout) -> Result<(), Error> {
-        &mut self,
-        addr: u8,
-        bytes: &[u8],
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
         // Send a START condition
 
         T::regs().cr1().modify(|reg| {
@@ -183,7 +116,7 @@ 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() {
-            check_timeout()?;
+            timeout.check()?;
         }
 
         // Also wait until signalled we're master and everything is waiting for us
@@ -193,7 +126,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             let sr2 = T::regs().sr2().read();
             !sr2.msl() && !sr2.busy()
         } {
-            check_timeout()?;
+            timeout.check()?;
         }
 
         // Set up current address, we're trying to talk to
@@ -203,7 +136,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         // 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() {
-            check_timeout()?;
+            timeout.check()?;
         }
 
         // Clear condition by reading SR2
@@ -211,20 +144,20 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
 
         // Send bytes
         for c in bytes {
-            self.send_byte(*c, &check_timeout)?;
+            self.send_byte(*c, timeout)?;
         }
 
         // Fallthrough is success
         Ok(())
     }
 
-    fn send_byte(&self, byte: u8, check_timeout: impl Fn() -> Result<(), Error>) -> Result<(), Error> {
+    fn send_byte(&self, byte: u8, timeout: Timeout) -> Result<(), Error> {
         // 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()
         } {
-            check_timeout()?;
+            timeout.check()?;
         }
 
         // Push out a byte of data
@@ -235,32 +168,27 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             // Check for any potential error conditions.
             !Self::check_and_clear_error_flags()?.btf()
         } {
-            check_timeout()?;
+            timeout.check()?;
         }
 
         Ok(())
     }
 
-    fn recv_byte(&self, check_timeout: impl Fn() -> Result<(), Error>) -> Result<u8, Error> {
+    fn recv_byte(&self, timeout: Timeout) -> Result<u8, Error> {
         while {
             // Check for any potential error conditions.
             Self::check_and_clear_error_flags()?;
 
             !T::regs().sr1().read().rxne()
         } {
-            check_timeout()?;
+            timeout.check()?;
         }
 
         let value = T::regs().dr().read().dr();
         Ok(value)
     }
 
-    pub fn blocking_read_timeout(
+    fn blocking_read_timeout(&mut self, addr: u8, buffer: &mut [u8], timeout: Timeout) -> Result<(), Error> {
-        &mut self,
-        addr: u8,
-        buffer: &mut [u8],
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
         if let Some((last, buffer)) = buffer.split_last_mut() {
             // Send a START condition and set ACK bit
             T::regs().cr1().modify(|reg| {
@@ -270,7 +198,7 @@ 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() {
-                check_timeout()?;
+                timeout.check()?;
             }
 
             // Also wait until signalled we're master and everything is waiting for us
@@ -278,7 +206,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
                 let sr2 = T::regs().sr2().read();
                 !sr2.msl() && !sr2.busy()
             } {
-                check_timeout()?;
+                timeout.check()?;
             }
 
             // Set up current address, we're trying to talk to
@@ -287,7 +215,7 @@ 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() {
-                check_timeout()?;
+                timeout.check()?;
             }
 
             // Clear condition by reading SR2
@@ -295,7 +223,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
 
             // Receive bytes into buffer
             for c in buffer {
-                *c = self.recv_byte(&check_timeout)?;
+                *c = self.recv_byte(timeout)?;
             }
 
             // Prepare to send NACK then STOP after next byte
@@ -305,11 +233,11 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             });
 
             // Receive last byte
-            *last = self.recv_byte(&check_timeout)?;
+            *last = self.recv_byte(timeout)?;
 
             // Wait for the STOP to be sent.
             while T::regs().cr1().read().stop() {
-                check_timeout()?;
+                timeout.check()?;
             }
 
             // Fallthrough is success
@@ -320,48 +248,33 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
     }
 
     pub fn blocking_read(&mut self, addr: u8, read: &mut [u8]) -> Result<(), Error> {
-        self.blocking_read_timeout(addr, read, || Ok(()))
+        self.blocking_read_timeout(addr, read, self.timeout())
     }
 
-    pub fn blocking_write_timeout(
+    pub fn blocking_write(&mut self, addr: u8, write: &[u8]) -> Result<(), Error> {
-        &mut self,
+        let timeout = self.timeout();
-        addr: u8,
+
-        write: &[u8],
+        self.write_bytes(addr, write, timeout)?;
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
-        self.write_bytes(addr, write, &check_timeout)?;
         // Send a STOP condition
         T::regs().cr1().modify(|reg| reg.set_stop(true));
         // Wait for STOP condition to transmit.
         while T::regs().cr1().read().stop() {
-            check_timeout()?;
+            timeout.check()?;
         }
 
         // Fallthrough is success
         Ok(())
     }
 
-    pub fn blocking_write(&mut self, addr: u8, write: &[u8]) -> Result<(), Error> {
+    pub fn blocking_write_read(&mut self, addr: u8, write: &[u8], read: &mut [u8]) -> Result<(), Error> {
-        self.blocking_write_timeout(addr, write, || Ok(()))
+        let timeout = self.timeout();
-    }
 
-    pub fn blocking_write_read_timeout(
+        self.write_bytes(addr, write, timeout)?;
-        &mut self,
+        self.blocking_read_timeout(addr, read, timeout)?;
-        addr: u8,
-        write: &[u8],
-        read: &mut [u8],
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
-        self.write_bytes(addr, write, &check_timeout)?;
-        self.blocking_read_timeout(addr, read, &check_timeout)?;
 
         Ok(())
     }
 
-    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

embassy-stm32/src/i2c/v2.rs

@@ -4,37 +4,13 @@ use core::task::Poll;
 
 use embassy_embedded_hal::SetConfig;
 use embassy_hal_internal::drop::OnDrop;
-use embassy_hal_internal::{into_ref, PeripheralRef};
-#[cfg(feature = "time")]
-use embassy_time::{Duration, Instant};
 
 use super::*;
-use crate::dma::{NoDma, Transfer};
+use crate::dma::Transfer;
-use crate::gpio::sealed::AFType;
-use crate::gpio::Pull;
-use crate::interrupt::typelevel::Interrupt;
 use crate::pac::i2c;
 use crate::time::Hertz;
-use crate::{interrupt, Peripheral};
 
-#[cfg(feature = "time")]
+pub(crate) unsafe fn on_interrupt<T: Instance>() {
-fn timeout_fn(timeout: Duration) -> impl Fn() -> Result<(), Error> {
-    let deadline = Instant::now() + timeout;
-    move || {
-        if Instant::now() > deadline {
-            Err(Error::Timeout)
-        } else {
-            Ok(())
-        }
-    }
-}
-
-#[cfg(not(feature = "time"))]
-pub fn no_timeout_fn() -> impl Fn() -> Result<(), Error> {
-    move || Ok(())
-}
-
-pub unsafe fn on_interrupt<T: Instance>() {
     let regs = T::regs();
     let isr = regs.isr().read();
 
@@ -48,70 +24,8 @@ pub unsafe fn on_interrupt<T: Instance>() {
     });
 }
 
-#[non_exhaustive]
-#[derive(Copy, Clone)]
-pub struct Config {
-    pub sda_pullup: bool,
-    pub scl_pullup: bool,
-    #[cfg(feature = "time")]
-    pub transaction_timeout: Duration,
-}
-
-impl Default for Config {
-    fn default() -> Self {
-        Self {
-            sda_pullup: false,
-            scl_pullup: false,
-            #[cfg(feature = "time")]
-            transaction_timeout: Duration::from_millis(100),
-        }
-    }
-}
-
-pub struct I2c<'d, T: Instance, TXDMA = NoDma, RXDMA = NoDma> {
-    _peri: PeripheralRef<'d, T>,
-    #[allow(dead_code)]
-    tx_dma: PeripheralRef<'d, TXDMA>,
-    #[allow(dead_code)]
-    rx_dma: PeripheralRef<'d, RXDMA>,
-    #[cfg(feature = "time")]
-    timeout: Duration,
-}
-
 impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
-    pub fn new(
+    pub(crate) fn init(&mut self, freq: Hertz, _config: Config) {
-        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::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,
-        config: Config,
-    ) -> Self {
-        into_ref!(peri, scl, sda, tx_dma, rx_dma);
-
-        T::enable_and_reset();
-
-        scl.set_as_af_pull(
-            scl.af_num(),
-            AFType::OutputOpenDrain,
-            match config.scl_pullup {
-                true => Pull::Up,
-                false => Pull::None,
-            },
-        );
-        sda.set_as_af_pull(
-            sda.af_num(),
-            AFType::OutputOpenDrain,
-            match config.sda_pullup {
-                true => Pull::Up,
-                false => Pull::None,
-            },
-        );
-
         T::regs().cr1().modify(|reg| {
             reg.set_pe(false);
             reg.set_anfoff(false);
@@ -130,17 +44,6 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         T::regs().cr1().modify(|reg| {
             reg.set_pe(true);
         });
-
-        unsafe { T::EventInterrupt::enable() };
-        unsafe { T::ErrorInterrupt::enable() };
-
-        Self {
-            _peri: peri,
-            tx_dma,
-            rx_dma,
-            #[cfg(feature = "time")]
-            timeout: config.transaction_timeout,
-        }
     }
 
     fn master_stop(&mut self) {
@@ -153,7 +56,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         stop: Stop,
         reload: bool,
         restart: bool,
-        check_timeout: impl Fn() -> Result<(), Error>,
+        timeout: Timeout,
     ) -> Result<(), Error> {
         assert!(length < 256);
 
@@ -162,7 +65,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             // automatically. This could be up to 50% of a bus
             // cycle (ie. up to 0.5/freq)
             while T::regs().cr2().read().start() {
-                check_timeout()?;
+                timeout.check()?;
             }
         }
 
@@ -189,20 +92,14 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         Ok(())
     }
 
-    fn master_write(
+    fn master_write(address: u8, length: usize, stop: Stop, reload: bool, timeout: Timeout) -> Result<(), Error> {
-        address: u8,
-        length: usize,
-        stop: Stop,
-        reload: bool,
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
         assert!(length < 256);
 
         // Wait for any previous address sequence to end
         // automatically. This could be up to 50% of a bus
         // cycle (ie. up to 0.5/freq)
         while T::regs().cr2().read().start() {
-            check_timeout()?;
+            timeout.check()?;
         }
 
         let reload = if reload {
@@ -227,15 +124,11 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         Ok(())
     }
 
-    fn master_continue(
+    fn master_continue(length: usize, reload: bool, timeout: Timeout) -> Result<(), Error> {
-        length: usize,
-        reload: bool,
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
         assert!(length < 256 && length > 0);
 
         while !T::regs().isr().read().tcr() {
-            check_timeout()?;
+            timeout.check()?;
         }
 
         let reload = if reload {
@@ -261,7 +154,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         }
     }
 
-    fn wait_txe(&self, check_timeout: impl Fn() -> Result<(), Error>) -> Result<(), Error> {
+    fn wait_txe(&self, timeout: Timeout) -> Result<(), Error> {
         loop {
             let isr = T::regs().isr().read();
             if isr.txe() {
@@ -278,11 +171,11 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
                 return Err(Error::Nack);
             }
 
-            check_timeout()?;
+            timeout.check()?;
         }
     }
 
-    fn wait_rxne(&self, check_timeout: impl Fn() -> Result<(), Error>) -> Result<(), Error> {
+    fn wait_rxne(&self, timeout: Timeout) -> Result<(), Error> {
         loop {
             let isr = T::regs().isr().read();
             if isr.rxne() {
@@ -299,11 +192,11 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
                 return Err(Error::Nack);
             }
 
-            check_timeout()?;
+            timeout.check()?;
         }
     }
 
-    fn wait_tc(&self, check_timeout: impl Fn() -> Result<(), Error>) -> Result<(), Error> {
+    fn wait_tc(&self, timeout: Timeout) -> Result<(), Error> {
         loop {
             let isr = T::regs().isr().read();
             if isr.tc() {
@@ -320,17 +213,11 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
                 return Err(Error::Nack);
             }
 
-            check_timeout()?;
+            timeout.check()?;
         }
     }
 
-    fn read_internal(
+    fn read_internal(&mut self, address: u8, read: &mut [u8], restart: bool, timeout: Timeout) -> Result<(), Error> {
-        &mut self,
-        address: u8,
-        read: &mut [u8],
-        restart: bool,
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
         let completed_chunks = read.len() / 255;
         let total_chunks = if completed_chunks * 255 == read.len() {
             completed_chunks
@@ -345,17 +232,17 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             Stop::Automatic,
             last_chunk_idx != 0,
             restart,
-            &check_timeout,
+            timeout,
         )?;
 
         for (number, chunk) in read.chunks_mut(255).enumerate() {
             if number != 0 {
-                Self::master_continue(chunk.len(), number != last_chunk_idx, &check_timeout)?;
+                Self::master_continue(chunk.len(), number != last_chunk_idx, timeout)?;
             }
 
             for byte in chunk {
                 // Wait until we have received something
-                self.wait_rxne(&check_timeout)?;
+                self.wait_rxne(timeout)?;
 
                 *byte = T::regs().rxdr().read().rxdata();
             }
@@ -363,13 +250,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         Ok(())
     }
 
-    fn write_internal(
+    fn write_internal(&mut self, address: u8, write: &[u8], send_stop: bool, timeout: Timeout) -> Result<(), Error> {
-        &mut self,
-        address: u8,
-        write: &[u8],
-        send_stop: bool,
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
         let completed_chunks = write.len() / 255;
         let total_chunks = if completed_chunks * 255 == write.len() {
             completed_chunks
@@ -386,7 +267,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             write.len().min(255),
             Stop::Software,
             last_chunk_idx != 0,
-            &check_timeout,
+            timeout,
         ) {
             if send_stop {
                 self.master_stop();
@@ -396,14 +277,14 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
 
         for (number, chunk) in write.chunks(255).enumerate() {
             if number != 0 {
-                Self::master_continue(chunk.len(), number != last_chunk_idx, &check_timeout)?;
+                Self::master_continue(chunk.len(), number != last_chunk_idx, timeout)?;
             }
 
             for byte in chunk {
                 // Wait until we are allowed to send data
                 // (START has been ACKed or last byte when
                 // through)
-                if let Err(err) = self.wait_txe(&check_timeout) {
+                if let Err(err) = self.wait_txe(timeout) {
                     if send_stop {
                         self.master_stop();
                     }
@@ -414,7 +295,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             }
         }
         // Wait until the write finishes
-        let result = self.wait_tc(&check_timeout);
+        let result = self.wait_tc(timeout);
         if send_stop {
             self.master_stop();
         }
@@ -427,7 +308,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         write: &[u8],
         first_slice: bool,
         last_slice: bool,
-        check_timeout: impl Fn() -> Result<(), Error>,
+        timeout: Timeout,
     ) -> Result<(), Error>
     where
         TXDMA: crate::i2c::TxDma<T>,
@@ -473,10 +354,10 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
                         total_len.min(255),
                         Stop::Software,
                         (total_len > 255) || !last_slice,
-                        &check_timeout,
+                        timeout,
                     )?;
                 } else {
-                    Self::master_continue(total_len.min(255), (total_len > 255) || !last_slice, &check_timeout)?;
+                    Self::master_continue(total_len.min(255), (total_len > 255) || !last_slice, timeout)?;
                     T::regs().cr1().modify(|w| w.set_tcie(true));
                 }
             } else if !(isr.tcr() || isr.tc()) {
@@ -487,7 +368,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             } else {
                 let last_piece = (remaining_len <= 255) && last_slice;
 
-                if let Err(e) = Self::master_continue(remaining_len.min(255), !last_piece, &check_timeout) {
+                if let Err(e) = Self::master_continue(remaining_len.min(255), !last_piece, timeout) {
                     return Poll::Ready(Err(e));
                 }
                 T::regs().cr1().modify(|w| w.set_tcie(true));
@@ -502,7 +383,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
 
         if last_slice {
             // This should be done already
-            self.wait_tc(&check_timeout)?;
+            self.wait_tc(timeout)?;
             self.master_stop();
         }
 
@@ -516,7 +397,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         address: u8,
         buffer: &mut [u8],
         restart: bool,
-        check_timeout: impl Fn() -> Result<(), Error>,
+        timeout: Timeout,
     ) -> Result<(), Error>
     where
         RXDMA: crate::i2c::RxDma<T>,
@@ -558,7 +439,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
                     Stop::Software,
                     total_len > 255,
                     restart,
-                    &check_timeout,
+                    timeout,
                 )?;
             } else if !(isr.tcr() || isr.tc()) {
                 // poll_fn was woken without an interrupt present
@@ -568,7 +449,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             } else {
                 let last_piece = remaining_len <= 255;
 
-                if let Err(e) = Self::master_continue(remaining_len.min(255), !last_piece, &check_timeout) {
+                if let Err(e) = Self::master_continue(remaining_len.min(255), !last_piece, timeout) {
                     return Poll::Ready(Err(e));
                 }
                 T::regs().cr1().modify(|w| w.set_tcie(true));
@@ -582,7 +463,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
         dma_transfer.await;
 
         // This should be done already
-        self.wait_tc(&check_timeout)?;
+        self.wait_tc(timeout)?;
         self.master_stop();
 
         drop(on_drop);
@@ -592,41 +473,31 @@ 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>,
-    {
-        if write.is_empty() {
-            self.write_internal(address, write, true, timeout_fn(self.timeout))
-        } else {
-            embassy_time::with_timeout(
-                self.timeout,
-                self.write_dma_internal(address, write, true, true, timeout_fn(self.timeout)),
-            )
-            .await
-            .unwrap_or(Err(Error::Timeout))
-        }
-    }
 
-    #[cfg(not(feature = "time"))]
+    /// Write.
     pub async fn write(&mut self, address: u8, write: &[u8]) -> Result<(), Error>
     where
         TXDMA: crate::i2c::TxDma<T>,
     {
+        let timeout = self.timeout();
         if write.is_empty() {
-            self.write_internal(address, write, true, no_timeout_fn())
+            self.write_internal(address, write, true, timeout)
         } else {
-            self.write_dma_internal(address, write, true, true, no_timeout_fn())
+            timeout
+                .with(self.write_dma_internal(address, write, true, true, timeout))
                 .await
         }
     }
 
-    #[cfg(feature = "time")]
+    /// Write multiple buffers.
+    ///
+    /// The buffers are concatenated in a single write transaction.
     pub async fn write_vectored(&mut self, address: u8, write: &[&[u8]]) -> Result<(), Error>
     where
         TXDMA: crate::i2c::TxDma<T>,
     {
+        let timeout = self.timeout();
+
         if write.is_empty() {
             return Err(Error::ZeroLengthTransfer);
         }
@@ -638,123 +509,49 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             let next = iter.next();
             let is_last = next.is_none();
 
-            embassy_time::with_timeout(
+            let fut = self.write_dma_internal(address, c, first, is_last, timeout);
-                self.timeout,
+            timeout.with(fut).await?;
-                self.write_dma_internal(address, c, first, is_last, timeout_fn(self.timeout)),
-            )
-            .await
-            .unwrap_or(Err(Error::Timeout))?;
             first = false;
             current = next;
         }
         Ok(())
     }
 
-    #[cfg(not(feature = "time"))]
+    /// Read.
-    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>,
     {
+        let timeout = self.timeout();
+
         if buffer.is_empty() {
-            self.read_internal(address, buffer, false, timeout_fn(self.timeout))
+            self.read_internal(address, buffer, false, timeout)
         } else {
-            embassy_time::with_timeout(
+            let fut = self.read_dma_internal(address, buffer, false, timeout);
-                self.timeout,
+            timeout.with(fut).await
-                self.read_dma_internal(address, buffer, false, timeout_fn(self.timeout)),
-            )
-            .await
-            .unwrap_or(Err(Error::Timeout))
         }
     }
 
-    #[cfg(not(feature = "time"))]
+    /// Write, restart, read.
-    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, no_timeout_fn())
-        } else {
-            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>,
     {
-        let start_instant = Instant::now();
+        let timeout = self.timeout();
-        let check_timeout = timeout_fn(self.timeout);
+
         if write.is_empty() {
-            self.write_internal(address, write, false, &check_timeout)?;
+            self.write_internal(address, write, false, timeout)?;
         } else {
-            embassy_time::with_timeout(
+            let fut = self.write_dma_internal(address, write, true, true, timeout);
-                self.timeout,
+            timeout.with(fut).await?;
-                self.write_dma_internal(address, write, true, true, &check_timeout),
-            )
-            .await
-            .unwrap_or(Err(Error::Timeout))?;
-        }
-
-        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)?;
-        } else {
-            embassy_time::with_timeout(
-                time_left_until_timeout,
-                self.read_dma_internal(address, read, true, &check_timeout),
-            )
-            .await
-            .unwrap_or(Err(Error::Timeout))?;
-        }
-
-        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)?;
+            self.read_internal(address, read, true, timeout)?;
         } else {
-            self.read_dma_internal(address, read, true, &no_timeout).await?;
+            let fut = self.read_dma_internal(address, read, true, timeout);
+            timeout.with(fut).await?;
         }
 
         Ok(())
@@ -763,105 +560,35 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
     // =========================
     //  Blocking public API
 
-    #[cfg(feature = "time")]
+    /// Blocking read.
-    pub fn blocking_read_timeout(&mut self, address: u8, read: &mut [u8], timeout: Duration) -> Result<(), Error> {
-        self.read_internal(address, read, false, timeout_fn(timeout))
-        // Automatic Stop
-    }
-
-    #[cfg(not(feature = "time"))]
-    pub fn blocking_read_timeout(
-        &mut self,
-        address: u8,
-        read: &mut [u8],
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
-        self.read_internal(address, read, false, check_timeout)
-        // Automatic Stop
-    }
-
-    #[cfg(feature = "time")]
     pub fn blocking_read(&mut self, address: u8, read: &mut [u8]) -> Result<(), Error> {
-        self.blocking_read_timeout(address, read, self.timeout)
+        self.read_internal(address, read, false, self.timeout())
-    }
-
-    #[cfg(not(feature = "time"))]
-    pub fn blocking_read(&mut self, address: u8, read: &mut [u8]) -> Result<(), Error> {
-        self.blocking_read_timeout(address, read, || Ok(()))
-    }
-
-    #[cfg(feature = "time")]
-    pub fn blocking_write_timeout(&mut self, address: u8, write: &[u8], timeout: Duration) -> Result<(), Error> {
-        self.write_internal(address, write, true, timeout_fn(timeout))
-    }
-
-    #[cfg(not(feature = "time"))]
-    pub fn blocking_write_timeout(
-        &mut self,
-        address: u8,
-        write: &[u8],
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
-        self.write_internal(address, write, true, check_timeout)
-    }
-
-    #[cfg(feature = "time")]
-    pub fn blocking_write(&mut self, address: u8, write: &[u8]) -> Result<(), Error> {
-        self.blocking_write_timeout(address, write, self.timeout)
-    }
-
-    #[cfg(not(feature = "time"))]
-    pub fn blocking_write(&mut self, address: u8, write: &[u8]) -> Result<(), Error> {
-        self.blocking_write_timeout(address, write, || Ok(()))
-    }
-
-    #[cfg(feature = "time")]
-    pub fn blocking_write_read_timeout(
-        &mut self,
-        address: u8,
-        write: &[u8],
-        read: &mut [u8],
-        timeout: Duration,
-    ) -> Result<(), Error> {
-        let check_timeout = timeout_fn(timeout);
-        self.write_internal(address, write, false, &check_timeout)?;
-        self.read_internal(address, read, true, &check_timeout)
         // Automatic Stop
     }
 
-    #[cfg(not(feature = "time"))]
+    /// Blocking write.
-    pub fn blocking_write_read_timeout(
+    pub fn blocking_write(&mut self, address: u8, write: &[u8]) -> Result<(), Error> {
-        &mut self,
+        self.write_internal(address, write, true, self.timeout())
-        address: u8,
+    }
-        write: &[u8],
+
-        read: &mut [u8],
+    /// Blocking write, restart, read.
-        check_timeout: impl Fn() -> Result<(), Error>,
+    pub fn blocking_write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Error> {
-    ) -> Result<(), Error> {
+        let timeout = self.timeout();
-        self.write_internal(address, write, false, &check_timeout)?;
+        self.write_internal(address, write, false, timeout)?;
-        self.read_internal(address, read, true, &check_timeout)
+        self.read_internal(address, read, true, timeout)
         // Automatic Stop
     }
 
-    #[cfg(feature = "time")]
+    /// Blocking write multiple buffers.
-    pub fn blocking_write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Error> {
+    ///
-        self.blocking_write_read_timeout(address, write, read, self.timeout)
+    /// The buffers are concatenated in a single write transaction.
-    }
+    pub fn blocking_write_vectored(&mut self, address: u8, write: &[&[u8]]) -> Result<(), Error> {
-
-    #[cfg(not(feature = "time"))]
-    pub fn blocking_write_read(&mut self, address: u8, write: &[u8], read: &mut [u8]) -> Result<(), Error> {
-        self.blocking_write_read_timeout(address, write, read, || Ok(()))
-    }
-
-    fn blocking_write_vectored_with_timeout(
-        &mut self,
-        address: u8,
-        write: &[&[u8]],
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
         if write.is_empty() {
             return Err(Error::ZeroLengthTransfer);
         }
 
+        let timeout = self.timeout();
+
         let first_length = write[0].len();
         let last_slice_index = write.len() - 1;
 
@@ -870,7 +597,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             first_length.min(255),
             Stop::Software,
             (first_length > 255) || (last_slice_index != 0),
-            &check_timeout,
+            timeout,
         ) {
             self.master_stop();
             return Err(err);
@@ -890,7 +617,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
                 if let Err(err) = Self::master_continue(
                     slice_len.min(255),
                     (idx != last_slice_index) || (slice_len > 255),
-                    &check_timeout,
+                    timeout,
                 ) {
                     self.master_stop();
                     return Err(err);
@@ -902,7 +629,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
                     if let Err(err) = Self::master_continue(
                         chunk.len(),
                         (number != last_chunk_idx) || (idx != last_slice_index),
-                        &check_timeout,
+                        timeout,
                     ) {
                         self.master_stop();
                         return Err(err);
@@ -913,7 +640,7 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
                     // Wait until we are allowed to send data
                     // (START has been ACKed or last byte when
                     // through)
-                    if let Err(err) = self.wait_txe(&check_timeout) {
+                    if let Err(err) = self.wait_txe(timeout) {
                         self.master_stop();
                         return Err(err);
                     }
@@ -925,41 +652,10 @@ impl<'d, T: Instance, TXDMA, RXDMA> I2c<'d, T, TXDMA, RXDMA> {
             }
         }
         // Wait until the write finishes
-        let result = self.wait_tc(&check_timeout);
+        let result = self.wait_tc(timeout);
         self.master_stop();
         result
     }
-
-    #[cfg(feature = "time")]
-    pub fn blocking_write_vectored_timeout(
-        &mut self,
-        address: u8,
-        write: &[&[u8]],
-        timeout: Duration,
-    ) -> Result<(), Error> {
-        let check_timeout = timeout_fn(timeout);
-        self.blocking_write_vectored_with_timeout(address, write, check_timeout)
-    }
-
-    #[cfg(not(feature = "time"))]
-    pub fn blocking_write_vectored_timeout(
-        &mut self,
-        address: u8,
-        write: &[&[u8]],
-        check_timeout: impl Fn() -> Result<(), Error>,
-    ) -> Result<(), Error> {
-        self.blocking_write_vectored_with_timeout(address, write, check_timeout)
-    }
-
-    #[cfg(feature = "time")]
-    pub fn blocking_write_vectored(&mut self, address: u8, write: &[&[u8]]) -> Result<(), Error> {
-        self.blocking_write_vectored_timeout(address, write, self.timeout)
-    }
-
-    #[cfg(not(feature = "time"))]
-    pub fn blocking_write_vectored(&mut self, address: u8, write: &[&[u8]]) -> Result<(), Error> {
-        self.blocking_write_vectored_timeout(address, write, || Ok(()))
-    }
 }
 
 impl<'d, T: Instance, TXDMA, RXDMA> Drop for I2c<'d, T, TXDMA, RXDMA> {