From 56cd05a7c9a1bbd621e74b305fef5ef55915b948 Mon Sep 17 00:00:00 2001
From: Henri Chataing <henrichataing@google.com>
Date: Thu, 23 Apr 2026 09:57:43 +0000
Subject: [PATCH] Add printf traces for LL HCI failure points (#54)

---
 rust/src/ffi.rs          | 10 ++++++----
 rust/src/llcp/manager.rs |  5 ++++-
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/rust/src/ffi.rs b/rust/src/ffi.rs
index 95a7cfe..7c70aa1 100644
--- a/rust/src/ffi.rs
+++ b/rust/src/ffi.rs
@@ -324,10 +324,12 @@ pub unsafe extern "C" fn link_layer_ingest_hci(
     let ll = Rc::get_mut(&mut ll).unwrap();
     let data = unsafe { slice::from_raw_parts(data, len) };
 
-    if let Ok(packet) = hci::Command::decode_full(data) {
-        ll.ingest_hci(packet).is_ok()
-    } else {
-        false
+    match hci::Command::decode_full(data) {
+        Ok(packet) => ll.ingest_hci(packet).is_ok(),
+        Err(err) => {
+            println!("failed to decode LL HCI command: {}", err);
+            false
+        }
     }
 }
 
diff --git a/rust/src/llcp/manager.rs b/rust/src/llcp/manager.rs
index d5ef9b3..f35f2d6 100644
--- a/rust/src/llcp/manager.rs
+++ b/rust/src/llcp/manager.rs
@@ -98,7 +98,10 @@ impl LinkLayer {
             Ok(LeRemoveIsoDataPath(packet)) => self.iso.hci_le_remove_iso_data_path(packet),
             Ok(LeCreateBig(packet)) => self.iso.hci_le_create_big(packet),
             Ok(LeTerminateBig(packet)) => self.iso.hci_le_terminate_big(packet),
-            _ => Err(LinkLayerError::UnhandledHciPacket)?,
+            _ => {
+                println!("Unhandled LL HCI command {:?}", packet.op_code);
+                Err(LinkLayerError::UnhandledHciPacket)?
+            }
         };
         Ok(())
     }