From f5d5f53914d46dfccdd21399e44f8af71a8f345a Mon Sep 17 00:00:00 2001
From: Kevin O'Connor <kevin@koconnor.net>
Date: Sat, 11 Jun 2022 18:19:53 -0400
Subject: [PATCH] stm32: Add support for disabling the canbus filter

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
---
 src/Kconfig       |  3 +++
 src/stm32/can.c   | 20 +++++++++++++-------
 src/stm32/fdcan.c |  2 ++
 3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/src/Kconfig b/src/Kconfig
index eba05243..79cb4182 100644
--- a/src/Kconfig
+++ b/src/Kconfig
@@ -83,6 +83,9 @@ config CANSERIAL
 config CANBUS_FREQUENCY
     int "CAN bus speed" if LOW_LEVEL_OPTIONS && CANSERIAL
     default 500000
+config CANBUS_FILTER
+    bool
+    default y if CANSERIAL
 
 # Support setting gpio state at startup
 config INITIAL_PINS
diff --git a/src/stm32/can.c b/src/stm32/can.c
index 9cd72209..6e50cea9 100644
--- a/src/stm32/can.c
+++ b/src/stm32/can.c
@@ -136,13 +136,19 @@ canbus_set_filter(uint32_t id)
     /* Initialisation mode for the filter */
     SOC_CAN->FA1R = 0;
 
-    uint32_t mask = CAN_TI0R_STID | CAN_TI0R_IDE | CAN_TI0R_RTR;
-    SOC_CAN->sFilterRegister[0].FR1 = CANBUS_ID_ADMIN << CAN_RI0R_STID_Pos;
-    SOC_CAN->sFilterRegister[0].FR2 = mask;
-    SOC_CAN->sFilterRegister[1].FR1 = (id + 1) << CAN_RI0R_STID_Pos;
-    SOC_CAN->sFilterRegister[1].FR2 = mask;
-    SOC_CAN->sFilterRegister[2].FR1 = id << CAN_RI0R_STID_Pos;
-    SOC_CAN->sFilterRegister[2].FR2 = mask;
+    if (CONFIG_CANBUS_FILTER) {
+        uint32_t mask = CAN_TI0R_STID | CAN_TI0R_IDE | CAN_TI0R_RTR;
+        SOC_CAN->sFilterRegister[0].FR1 = CANBUS_ID_ADMIN << CAN_RI0R_STID_Pos;
+        SOC_CAN->sFilterRegister[0].FR2 = mask;
+        SOC_CAN->sFilterRegister[1].FR1 = (id + 1) << CAN_RI0R_STID_Pos;
+        SOC_CAN->sFilterRegister[1].FR2 = mask;
+        SOC_CAN->sFilterRegister[2].FR1 = id << CAN_RI0R_STID_Pos;
+        SOC_CAN->sFilterRegister[2].FR2 = mask;
+    } else {
+        SOC_CAN->sFilterRegister[0].FR1 = 0;
+        SOC_CAN->sFilterRegister[0].FR2 = 0;
+        id = 0;
+    }
 
     /* 32-bit scale for the filter */
     SOC_CAN->FS1R = (1<<0) | (1<<1) | (1<<2);
diff --git a/src/stm32/fdcan.c b/src/stm32/fdcan.c
index cf2cc276..3af9ffa8 100755
--- a/src/stm32/fdcan.c
+++ b/src/stm32/fdcan.c
@@ -113,6 +113,8 @@ can_filter(uint32_t index, uint32_t id)
 void
 canbus_set_filter(uint32_t id)
 {
+    if (!CONFIG_CANBUS_FILTER)
+        return;
     /* Request initialisation */
     SOC_CAN->CCCR |= FDCAN_CCCR_INIT;
     /* Wait the acknowledge */