4 files changed, 7 insertions, 3 deletions

diff --git a/embassy-embedded-hal/Cargo.toml b/embassy-embedded-hal/Cargo.toml
index d2606d264..455786be9 100644
--- a/embassy-embedded-hal/Cargo.toml
+++ b/embassy-embedded-hal/Cargo.toml
@@ -15,4 +15,6 @@ embedded-hal-1 = { package = "embedded-hal", version = "1.0.0-alpha.8" }
 embedded-hal-async = { version = "0.1.0-alpha.1", optional = true }
 embedded-storage = "0.3.0"
 embedded-storage-async = { version = "0.3.0", optional = true }
-nb = "1.0.0"
\ No newline at end of file
+nb = "1.0.0"
+
+defmt = { version = "0.3", optional = true }
diff --git a/embassy-embedded-hal/src/shared_bus/mod.rs b/embassy-embedded-hal/src/shared_bus/mod.rs
index 76ee413d9..617d921e9 100644
--- a/embassy-embedded-hal/src/shared_bus/mod.rs
+++ b/embassy-embedded-hal/src/shared_bus/mod.rs
@@ -10,6 +10,7 @@ pub mod blocking;
 
 /// Error returned by I2C device implementations in this crate.
 #[derive(Copy, Clone, Eq, PartialEq, Debug)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum I2cDeviceError<BUS> {
     /// An operation on the inner I2C bus failed.
     I2c(BUS),
@@ -28,6 +29,7 @@ where
 
 /// Error returned by SPI device implementations in this crate.
 #[derive(Copy, Clone, Eq, PartialEq, Debug)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum SpiDeviceError<BUS, CS> {
     /// An operation on the inner SPI bus failed.
     Spi(BUS),
diff --git a/embassy-nrf/Cargo.toml b/embassy-nrf/Cargo.toml
index 3569a70c6..b2b6db1cd 100644
--- a/embassy-nrf/Cargo.toml
+++ b/embassy-nrf/Cargo.toml
@@ -18,7 +18,7 @@ flavors = [
 
 time = ["embassy/time"]
 
-defmt = ["dep:defmt", "embassy/defmt", "embassy-usb?/defmt", "embedded-io?/defmt"]
+defmt = ["dep:defmt", "embassy/defmt", "embassy-usb?/defmt", "embedded-io?/defmt", "embassy-embedded-hal/defmt"]
 
 # Enable nightly-only features
 nightly = ["embassy/nightly", "embedded-hal-1", "embedded-hal-async", "embassy-usb", "embedded-storage-async", "dep:embedded-io", "embassy-embedded-hal/nightly"]
diff --git a/embassy-stm32/Cargo.toml b/embassy-stm32/Cargo.toml
index a5c444fbb..e9c3fdf45 100644
--- a/embassy-stm32/Cargo.toml
+++ b/embassy-stm32/Cargo.toml
@@ -72,7 +72,7 @@ quote = "1.0.15"
 stm32-metapac = { version = "0.1.0", path = "../stm32-metapac", default-features = false, features = ["metadata"]}
 
 [features]
-defmt = ["dep:defmt", "bxcan/unstable-defmt", "embassy/defmt", "embedded-io?/defmt", "embassy-usb?/defmt"]
+defmt = ["dep:defmt", "bxcan/unstable-defmt", "embassy/defmt", "embassy-embedded-hal/defmt", "embedded-io?/defmt", "embassy-usb?/defmt"]
 sdmmc-rs = ["embedded-sdmmc"]
 net = ["embassy-net" ]
 memory-x = ["stm32-metapac/memory-x"]