Added two new constructors to ExclusiveDevice to allow for SPI devices that don't require a CS pin

embedded-hal-bus/Cargo.toml

@@ -37,6 +37,7 @@ embedded-hal-async = { version = "1.0.0", path = "../embedded-hal-async", option
 critical-section = { version = "1.0" }
 defmt-03 = { package = "defmt", version = "0.3", optional = true }
 portable-atomic = {version = "1.3", default-features = false, optional = true, features = ["require-cas"]}
+unwrap-infallible = "0.1.5"
 
 [package.metadata.docs.rs]
 features = ["std", "async"]

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

@@ -1,7 +1,7 @@
 //! SPI bus sharing mechanisms.
 
 use embedded_hal::delay::DelayNs;
-use embedded_hal::digital::OutputPin;
+use embedded_hal::digital::{NoPin, OutputPin};
 use embedded_hal::spi::{ErrorType, Operation, SpiBus, SpiDevice};
 #[cfg(feature = "async")]
 use embedded_hal_async::{
@@ -49,6 +49,15 @@ impl<BUS, CS, D> ExclusiveDevice<BUS, CS, D> {
     }
 }
 
+use unwrap_infallible::UnwrapInfallible;
+
+impl<BUS, D> ExclusiveDevice<BUS, NoPin, D> {
+    /// Create a new [`ExclusiveDevice`] without a Chip Select (CS) pin.
+    pub fn new_no_cs(bus: BUS, delay: D) -> Self {
+        ExclusiveDevice::new(bus, NoPin, delay).unwrap_infallible()
+    }
+}
+
 impl<BUS, CS> ExclusiveDevice<BUS, CS, super::NoDelay> {
     /// Create a new [`ExclusiveDevice`] without support for in-transaction delays.
     ///
@@ -83,6 +92,13 @@ impl<BUS, CS> ExclusiveDevice<BUS, CS, super::NoDelay> {
     }
 }
 
+impl<BUS> ExclusiveDevice<BUS, NoPin, super::NoDelay> {
+    /// Create a new [`ExclusiveDevice`] without a Chip Select (CS) pin.
+    pub fn new_no_cs_no_delay(bus: BUS) -> Self {
+        ExclusiveDevice::new_no_delay(bus, NoPin).unwrap_infallible()
+    }
+}
+
 impl<BUS, CS, D> ErrorType for ExclusiveDevice<BUS, CS, D>
 where
     BUS: ErrorType,

embedded-hal/src/digital.rs

@@ -222,3 +222,27 @@ impl<T: InputPin + ?Sized> InputPin for &mut T {
         T::is_low(self)
     }
 }
+
+use core::convert::Infallible;
+use ErrorType as NoPinErrorType;
+
+/// A dummy pin that does nothing.
+/// This can be used for devices that do not require a Chip Select (CS) pin.
+#[derive(Debug, Default, Copy, Clone)]
+pub struct NoPin;
+
+// Implement `ErrorType` for NoPin (Explicitly Using `digital::ErrorType`)
+impl NoPinErrorType for NoPin {
+    type Error = Infallible;
+}
+
+// Implement `OutputPin`
+impl OutputPin for NoPin {
+    fn set_low(&mut self) -> Result<(), Infallible> {
+        Ok(())
+    }
+
+    fn set_high(&mut self) -> Result<(), Infallible> {
+        Ok(())
+    }
+}