diff --git a/embedded-hal/CHANGELOG.md b/embedded-hal/CHANGELOG.md
index 9d3ac625b..00c663582 100644
--- a/embedded-hal/CHANGELOG.md
+++ b/embedded-hal/CHANGELOG.md
@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ## [Unreleased]
 
 - gpio: remove `ToggleableOutputPin`, move `toggle()` to `StatefulOutputPin`.
+- gpio: *don't* require `&mut self` in `InputPin` and `StatefulOutputPin`.
 
 ## [v1.0.0-rc.3] - 2023-12-14
 
diff --git a/embedded-hal/src/digital.rs b/embedded-hal/src/digital.rs
index afcf03963..ef2fe1784 100644
--- a/embedded-hal/src/digital.rs
+++ b/embedded-hal/src/digital.rs
@@ -169,12 +169,12 @@ pub trait StatefulOutputPin: OutputPin {
     /// Is the pin in drive high mode?
     ///
     /// *NOTE* this does *not* read the electrical state of the pin.
-    fn is_set_high(&mut self) -> Result<bool, Self::Error>;
+    fn is_set_high(&self) -> Result<bool, Self::Error>;
 
     /// Is the pin in drive low mode?
     ///
     /// *NOTE* this does *not* read the electrical state of the pin.
-    fn is_set_low(&mut self) -> Result<bool, Self::Error>;
+    fn is_set_low(&self) -> Result<bool, Self::Error>;
 
     /// Toggle pin output.
     fn toggle(&mut self) -> Result<(), Self::Error> {
@@ -185,12 +185,12 @@ pub trait StatefulOutputPin: OutputPin {
 
 impl<T: StatefulOutputPin + ?Sized> StatefulOutputPin for &mut T {
     #[inline]
-    fn is_set_high(&mut self) -> Result<bool, Self::Error> {
+    fn is_set_high(&self) -> Result<bool, Self::Error> {
         T::is_set_high(self)
     }
 
     #[inline]
-    fn is_set_low(&mut self) -> Result<bool, Self::Error> {
+    fn is_set_low(&self) -> Result<bool, Self::Error> {
         T::is_set_low(self)
     }
 
@@ -203,20 +203,20 @@ impl<T: StatefulOutputPin + ?Sized> StatefulOutputPin for &mut T {
 /// Single digital input pin.
 pub trait InputPin: ErrorType {
     /// Is the input pin high?
-    fn is_high(&mut self) -> Result<bool, Self::Error>;
+    fn is_high(&self) -> Result<bool, Self::Error>;
 
     /// Is the input pin low?
-    fn is_low(&mut self) -> Result<bool, Self::Error>;
+    fn is_low(&self) -> Result<bool, Self::Error>;
 }
 
-impl<T: InputPin + ?Sized> InputPin for &mut T {
+impl<T: InputPin + ?Sized> InputPin for &T {
     #[inline]
-    fn is_high(&mut self) -> Result<bool, Self::Error> {
+    fn is_high(&self) -> Result<bool, Self::Error> {
         T::is_high(self)
     }
 
     #[inline]
-    fn is_low(&mut self) -> Result<bool, Self::Error> {
+    fn is_low(&self) -> Result<bool, Self::Error> {
         T::is_low(self)
     }
 }