From 17d3adac4b9f1fe4458faba8fa467d13cf1ceac1 Mon Sep 17 00:00:00 2001
From: Adam Greig <adam@adamgreig.com>
Date: Fri, 18 Apr 2025 17:19:21 +0100
Subject: [PATCH] STM32: Fix CAN transmit on bxcan targets

---
 embassy-stm32/src/can/bxcan/registers.rs | 4 ++--
 embassy-stm32/src/can/fd/peripheral.rs   | 2 +-
 embassy-stm32/src/can/frame.rs           | 5 +++++
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/embassy-stm32/src/can/bxcan/registers.rs b/embassy-stm32/src/can/bxcan/registers.rs
index c5467dfe8..c295b0f50 100644
--- a/embassy-stm32/src/can/bxcan/registers.rs
+++ b/embassy-stm32/src/can/bxcan/registers.rs
@@ -299,9 +299,9 @@ impl Registers {
         mb.tdtr().write(|w| w.set_dlc(frame.header().len() as u8));
 
         mb.tdlr()
-            .write(|w| w.0 = u32::from_ne_bytes(unwrap!(frame.data()[0..4].try_into())));
+            .write(|w| w.0 = u32::from_ne_bytes(unwrap!(frame.raw_data()[0..4].try_into())));
         mb.tdhr()
-            .write(|w| w.0 = u32::from_ne_bytes(unwrap!(frame.data()[4..8].try_into())));
+            .write(|w| w.0 = u32::from_ne_bytes(unwrap!(frame.raw_data()[4..8].try_into())));
         let id: IdReg = frame.id().into();
         mb.tir().write(|w| {
             w.0 = id.0;
diff --git a/embassy-stm32/src/can/fd/peripheral.rs b/embassy-stm32/src/can/fd/peripheral.rs
index 014f31c87..4873ee444 100644
--- a/embassy-stm32/src/can/fd/peripheral.rs
+++ b/embassy-stm32/src/can/fd/peripheral.rs
@@ -75,7 +75,7 @@ impl Registers {
         let mailbox = self.tx_buffer_element(bufidx);
         mailbox.reset();
         put_tx_header(mailbox, header);
-        put_tx_data(mailbox, &buffer[..header.len() as usize]);
+        put_tx_data(mailbox, buffer);
 
         // Set <idx as Mailbox> as ready to transmit
         self.regs.txbar().modify(|w| w.set_ar(bufidx, true));
diff --git a/embassy-stm32/src/can/frame.rs b/embassy-stm32/src/can/frame.rs
index a1d773f2c..a4d5a9752 100644
--- a/embassy-stm32/src/can/frame.rs
+++ b/embassy-stm32/src/can/frame.rs
@@ -212,6 +212,11 @@ impl Frame {
         &self.data.raw()[..self.can_header.len as usize]
     }
 
+    /// Get reference to underlying 8-byte raw data buffer
+    pub(crate) fn raw_data(&self) -> &[u8] {
+        self.data.raw()
+    }
+
     /// Get mutable reference to data
     pub fn data_mut(&mut self) -> &mut [u8] {
         &mut self.data.raw_mut()[..self.can_header.len as usize]