Remove features that enable atomic-polyfill flags

embedded-hal-bus/Cargo.toml

@@ -17,23 +17,17 @@ version = "0.2.0"
 [features]
 # Enable shared bus implementations using `std::sync::Mutex`, and implement `std::error::Error` for `DeviceError`
 std = []
-# Enable shared bus implementations that require Atomic CAS operations
-atomic-device = []
+# Use `portable-atomic` to enable `atomic-device` on devices without native atomic CAS
+#
+# `portable-atomic` emulates atomic CAS functionality, allowing `embedded-hal-bus` to use `atomic-device` on hardware
+# that does not natively support atomic CAS. If you enable this, you must also add `portable-atomic` to your crate with
+# a feature flag such as `unsafe-assume-single-core` or `critical-section` to choose how atomic CAS is implemented.
+# See https://docs.rs/portable-atomic/1.7.0/portable_atomic/#optional-features for more info.
+portable-atomic = []
 # Enable `embedded-hal-async` support.
 async = ["dep:embedded-hal-async"]
 # Derive `defmt::Format` from `defmt` 0.3 for enums and structs. See https://github.com/knurling-rs/defmt for more info
 defmt-03 = ["dep:defmt-03", "embedded-hal/defmt-03", "embedded-hal-async?/defmt-03"]
-# Enable critical-section feature in portable-atomic.
-#
-# `portable-atomic` emulates atomic CAS functionality, allowing `embedded-hal-bus` to use `atomic-device` on hardware that does not natively support atomic CAS.
-# This feature requires a critical-section implementation, which is most often provided by your arch crate (cortex-m / riscv / msp430 / avr-device / etc) when the `critical-section-single-core` feature is enabled.
-# A list of critical-section impls is available [in the critical section docs](https://github.com/rust-embedded/critical-section?tab=readme-ov-file#usage-in-no-std-binaries)
-portable-atomic-critical-section = ["atomic-device", "portable-atomic/critical-section"]
-# Enable unsafe-assume-single-core feature of portable-atomic.
-# 
-# `portable-atomic` emulates atomic CAS functionality, allowing `embedded-hal-bus` to use `atomic-device` on hardware that does not natively support atomic CAS.
-#  This feature is only safe on single core systems
-portable-atomic-unsafe-assume-single-core = ["atomic-device", "portable-atomic/unsafe-assume-single-core"]
 
 [dependencies]
 embedded-hal = { version = "1.0.0", path = "../embedded-hal" }

embedded-hal-bus/README.md

@@ -31,17 +31,13 @@ provides mechanisms to obtain multiple `I2c` instances out of a single `I2c` ins
 ## Optional Cargo features
 
 - **`async`**: enable `embedded-hal-async` support.
-- **`atomic-device`**: enable shared bus implementations that require Atomic CAS operations.
 - **`defmt-03`**: Derive `defmt::Format` from `defmt` 0.3 for enums and structs.
-- **`portable-atomic-critical-section`**: Enable critical-section feature in portable-atomic.
+- **`portable-atomic`**: Use `portable-atomic` to enable `atomic-device` on devices without native atomic CAS
 
-  `portable-atomic` emulates atomic CAS functionality, allowing `embedded-hal-bus` to use `atomic-device` on hardware that does not natively support atomic CAS.
-  This feature requires a critical-section implementation, which is most often provided by your arch crate (cortex-m / riscv / msp430 / avr-device / etc) when the `critical-section-single-core` feature is enabled.
-  A list of critical-section impls is available [in the critical section docs](https://github.com/rust-embedded/critical-section?tab=readme-ov-file#usage-in-no-std-binaries)
-- **`portable-atomic-unsafe-assume-single-core`**: Enable unsafe-assume-single-core feature of portable-atomic.
-
-  `portable-atomic` emulates atomic CAS functionality, allowing `embedded-hal-bus` to use `atomic-device` on hardware that does not natively support atomic CAS.
-  This feature is only safe on single core systems
+  `portable-atomic` emulates atomic CAS functionality, allowing `embedded-hal-bus` to use `atomic-device` on hardware
+  that does not natively support atomic CAS. If you enable this, you must also add `portable-atomic` to your crate with
+  a feature flag such as `unsafe-assume-single-core` or `critical-section` to choose how atomic CAS is implemented.
+  See https://docs.rs/portable-atomic/1.7.0/portable_atomic/#optional-features for more info.
 - **`std`**: enable shared bus implementations using `std::sync::Mutex`, and implement
   `std::error::Error` for `DeviceError`.
 

embedded-hal-bus/src/i2c/mod.rs

@@ -8,7 +8,7 @@ mod mutex;
 pub use mutex::*;
 mod critical_section;
 pub use self::critical_section::*;
-#[cfg(any(feature = "atomic-device", target_has_atomic = "8"))]
+#[cfg(any(feature = "portable-atomic", target_has_atomic = "8"))]
 mod atomic;
-#[cfg(any(feature = "atomic-device", target_has_atomic = "8"))]
+#[cfg(any(feature = "portable-atomic", target_has_atomic = "8"))]
 pub use atomic::*;

embedded-hal-bus/src/spi/mod.rs

@@ -11,11 +11,11 @@ pub use refcell::*;
 mod mutex;
 #[cfg(feature = "std")]
 pub use mutex::*;
-#[cfg(any(feature = "atomic-device", target_has_atomic = "8"))]
+#[cfg(any(feature = "portable-atomic", target_has_atomic = "8"))]
 mod atomic;
 mod critical_section;
 mod shared;
-#[cfg(any(feature = "atomic-device", target_has_atomic = "8"))]
+#[cfg(any(feature = "portable-atomic", target_has_atomic = "8"))]
 pub use atomic::*;
 
 pub use self::critical_section::*;

embedded-hal-bus/src/util.rs

@@ -3,7 +3,7 @@
 #[allow(unused_imports)]
 use core::cell::UnsafeCell;
 
-#[cfg(any(feature = "atomic-device", target_has_atomic = "8"))]
+#[cfg(any(feature = "portable-atomic", target_has_atomic = "8"))]
 /// Cell type used by [`spi::AtomicDevice`](crate::spi::AtomicDevice) and [`i2c::AtomicDevice`](crate::i2c::AtomicDevice).
 ///
 /// To use `AtomicDevice`, you must wrap the bus with this struct, and then
@@ -12,12 +12,12 @@ pub struct AtomicCell<BUS> {
     pub(crate) bus: UnsafeCell<BUS>,
     pub(crate) busy: portable_atomic::AtomicBool,
 }
-#[cfg(any(feature = "atomic-device", target_has_atomic = "8"))]
+#[cfg(any(feature = "portable-atomic", target_has_atomic = "8"))]
 unsafe impl<BUS: Send> Send for AtomicCell<BUS> {}
-#[cfg(any(feature = "atomic-device", target_has_atomic = "8"))]
+#[cfg(any(feature = "portable-atomic", target_has_atomic = "8"))]
 unsafe impl<BUS: Send> Sync for AtomicCell<BUS> {}
 
-#[cfg(any(feature = "atomic-device", target_has_atomic = "8"))]
+#[cfg(any(feature = "portable-atomic", target_has_atomic = "8"))]
 impl<BUS> AtomicCell<BUS> {
     /// Create a new `AtomicCell`
     pub fn new(bus: BUS) -> Self {