2 files changed, 44 insertions, 2 deletions

diff --git a/embassy-hal-internal/Cargo.toml b/embassy-hal-internal/Cargo.toml
index b4c52ccfa..11dcc2466 100644
--- a/embassy-hal-internal/Cargo.toml
+++ b/embassy-hal-internal/Cargo.toml
@@ -14,6 +14,9 @@ categories = [
 
 [features]
 
+defmt = ["dep:defmt"]
+log = ["dep:log"]
+
 # Define the number of NVIC priority bits.
 prio-bits-0 = []
 prio-bits-1 = []
diff --git a/embassy-hal-internal/src/atomic_ring_buffer.rs b/embassy-hal-internal/src/atomic_ring_buffer.rs
index 00b7a1249..8c3889b85 100644
--- a/embassy-hal-internal/src/atomic_ring_buffer.rs
+++ b/embassy-hal-internal/src/atomic_ring_buffer.rs
@@ -133,6 +133,18 @@ impl RingBuffer {
         self.len.load(Ordering::Relaxed)
     }
 
+    /// Return number of items available to read.
+    pub fn available(&self) -> usize {
+        let end = self.end.load(Ordering::Relaxed);
+        let len = self.len.load(Ordering::Relaxed);
+        let start = self.start.load(Ordering::Relaxed);
+        if end >= start {
+            end - start
+        } else {
+            2 * len - start + end
+        }
+    }
+
     /// Check if buffer is full.
     pub fn is_full(&self) -> bool {
         let len = self.len.load(Ordering::Relaxed);
@@ -142,6 +154,11 @@ impl RingBuffer {
         self.wrap(start + len) == end
     }
 
+    /// Check if buffer is at least half full.
+    pub fn is_half_full(&self) -> bool {
+        self.available() >= self.len.load(Ordering::Relaxed) / 2
+    }
+
     /// Check if buffer is empty.
     pub fn is_empty(&self) -> bool {
         let start = self.start.load(Ordering::Relaxed);
@@ -394,6 +411,7 @@ mod tests {
             rb.init(b.as_mut_ptr(), 4);
 
             assert_eq!(rb.is_empty(), true);
+            assert_eq!(rb.is_half_full(), false);
             assert_eq!(rb.is_full(), false);
 
             rb.writer().push(|buf| {
@@ -406,6 +424,7 @@ mod tests {
             });
 
             assert_eq!(rb.is_empty(), false);
+            assert_eq!(rb.is_half_full(), true);
             assert_eq!(rb.is_full(), true);
 
             rb.writer().push(|buf| {
@@ -415,6 +434,7 @@ mod tests {
             });
 
             assert_eq!(rb.is_empty(), false);
+            assert_eq!(rb.is_half_full(), true);
             assert_eq!(rb.is_full(), true);
 
             rb.reader().pop(|buf| {
@@ -424,6 +444,7 @@ mod tests {
             });
 
             assert_eq!(rb.is_empty(), false);
+            assert_eq!(rb.is_half_full(), true);
             assert_eq!(rb.is_full(), false);
 
             rb.reader().pop(|buf| {
@@ -432,6 +453,7 @@ mod tests {
             });
 
             assert_eq!(rb.is_empty(), false);
+            assert_eq!(rb.is_half_full(), true);
             assert_eq!(rb.is_full(), false);
 
             rb.reader().pop(|buf| {
@@ -447,6 +469,7 @@ mod tests {
             });
 
             assert_eq!(rb.is_empty(), true);
+            assert_eq!(rb.is_half_full(), false);
             assert_eq!(rb.is_full(), false);
 
             rb.reader().pop(|buf| {
@@ -460,14 +483,28 @@ mod tests {
                 1
             });
 
+            assert_eq!(rb.is_empty(), false);
+            assert_eq!(rb.is_half_full(), false);
+            assert_eq!(rb.is_full(), false);
+
             rb.writer().push(|buf| {
                 assert_eq!(3, buf.len());
                 buf[0] = 11;
-                buf[1] = 12;
-                2
+                1
+            });
+
+            assert_eq!(rb.is_empty(), false);
+            assert_eq!(rb.is_half_full(), true);
+            assert_eq!(rb.is_full(), false);
+
+            rb.writer().push(|buf| {
+                assert_eq!(2, buf.len());
+                buf[0] = 12;
+                1
             });
 
             assert_eq!(rb.is_empty(), false);
+            assert_eq!(rb.is_half_full(), true);
             assert_eq!(rb.is_full(), false);
 
             rb.writer().push(|buf| {
@@ -477,6 +514,7 @@ mod tests {
             });
 
             assert_eq!(rb.is_empty(), false);
+            assert_eq!(rb.is_half_full(), true);
             assert_eq!(rb.is_full(), true);
         }
     }
@@ -490,6 +528,7 @@ mod tests {
             rb.init(b.as_mut_ptr(), b.len());
 
             assert_eq!(rb.is_empty(), true);
+            assert_eq!(rb.is_half_full(), true);
             assert_eq!(rb.is_full(), true);
 
             rb.writer().push(|buf| {