shared_bus/blocking/spi: fix build and behaviour when "time" disabled

new behaviour: check for DelayUs presence in operations instead of
shortcircuiting

1 files changed, 10 insertions, 2 deletions

diff --git a/embassy-embedded-hal/src/shared_bus/blocking/spi.rs b/embassy-embedded-hal/src/shared_bus/blocking/spi.rs
index feb0f5b7d..2b67862ea 100644
--- a/embassy-embedded-hal/src/shared_bus/blocking/spi.rs
+++ b/embassy-embedded-hal/src/shared_bus/blocking/spi.rs
@@ -55,6 +55,10 @@ where
     CS: OutputPin,
 {
     fn transaction(&mut self, operations: &mut [Operation<'_, u8>]) -> Result<(), Self::Error> {
+        if cfg!(not(feature = "time")) && operations.iter().any(|op| matches!(op, Operation::DelayUs(_))) {
+            return Err(SpiDeviceError::DelayUsNotSupported);
+        }
+
         self.bus.lock(|bus| {
             let mut bus = bus.borrow_mut();
             self.cs.set_low().map_err(SpiDeviceError::Cs)?;
@@ -65,7 +69,7 @@ where
                 Operation::Transfer(read, write) => bus.transfer(read, write),
                 Operation::TransferInPlace(buf) => bus.transfer_in_place(buf),
                 #[cfg(not(feature = "time"))]
-                Operation::DelayUs(_) => Err(SpiDeviceError::DelayUsNotSupported),
+                Operation::DelayUs(_) => unreachable!(),
                 #[cfg(feature = "time")]
                 Operation::DelayUs(us) => {
                     embassy_time::block_for(embassy_time::Duration::from_micros(*us as _));
@@ -161,6 +165,10 @@ where
     CS: OutputPin,
 {
     fn transaction(&mut self, operations: &mut [Operation<'_, u8>]) -> Result<(), Self::Error> {
+        if cfg!(not(feature = "time")) && operations.iter().any(|op| matches!(op, Operation::DelayUs(_))) {
+            return Err(SpiDeviceError::DelayUsNotSupported);
+        }
+
         self.bus.lock(|bus| {
             let mut bus = bus.borrow_mut();
             bus.set_config(&self.config).map_err(|_| SpiDeviceError::Config)?;
@@ -172,7 +180,7 @@ where
                 Operation::Transfer(read, write) => bus.transfer(read, write),
                 Operation::TransferInPlace(buf) => bus.transfer_in_place(buf),
                 #[cfg(not(feature = "time"))]
-                Operation::DelayUs(_) => Err(SpiDeviceError::DelayUsNotSupported),
+                Operation::DelayUs(_) => unreachable!(),
                 #[cfg(feature = "time")]
                 Operation::DelayUs(us) => {
                     embassy_time::block_for(embassy_time::Duration::from_micros(*us as _));