feat: automatic CAN filter configuration

inc/rtcan.h

@@ -215,6 +215,16 @@ typedef struct
  */
  atomic_bool rx_ready;
 
+ /**
+ * @brief Current subscriber number
+ */
+ uint32_t subscriber_number;
+
+ /**
+ * @brief Table that holds 4 consecutive can_ids for filter bank configuration
+ */
+ uint32_t can_ids[4];
+
 } rtcan_handle_t;
 
 /*

src/rtcan.c

@@ -15,6 +15,8 @@
  * thread constants
  */
 #define RTCAN_THREAD_STACK_SIZE 1024 // TODO: this needs to be profiled
+#define NUM_FILTERS 28
+#define NUM_IDS_PER_FILTER 4
 
 /*
  * useful macros
@@ -58,6 +60,12 @@ rtcan_status_t rtcan_init(rtcan_handle_t* rtcan_h,
  rtcan_h->err = RTCAN_ERROR_NONE;
  atomic_store(&rtcan_h->rx_ready, true);
 
+ rtcan_h->subscriber_number = 0;
+ for(int i = 0; i <4 ; i++)
+ {
+ rtcan_h->can_ids[i] = 0;
+ }
+
  // threads
  void* stack_ptr = NULL;
 
@@ -179,26 +187,6 @@ rtcan_status_t rtcan_init(rtcan_handle_t* rtcan_h,
  ADD_ERROR_IF(tx_status != TX_SUCCESS, RTCAN_ERROR_INTERNAL, rtcan_h);
  }
 
- // TODO: configure CAN filters
- if (no_errors(rtcan_h))
- {
- CAN_FilterTypeDef filter;
- filter.FilterActivation = ENABLE;
- filter.FilterFIFOAssignment = CAN_FILTER_FIFO0;
- filter.FilterIdHigh = 0x0000 << 5U;
- filter.FilterIdLow = 0x0000 << 5U;
- filter.FilterMaskIdHigh = 0x0000 << 5U;
- filter.FilterMaskIdLow = 0x0000 << 5U;
- filter.FilterMode = CAN_FILTERMODE_IDMASK;
- filter.FilterScale = CAN_FILTERSCALE_16BIT;
- filter.FilterBank = 0;
-
- HAL_StatusTypeDef hal_status = HAL_CAN_ConfigFilter(rtcan_h->hcan, 
- &filter);
-
- ADD_ERROR_IF(hal_status != HAL_OK, RTCAN_ERROR_INIT, rtcan_h);
- }
-
  return create_status(rtcan_h);
 }
 
@@ -209,6 +197,7 @@ rtcan_status_t rtcan_init(rtcan_handle_t* rtcan_h,
  */
 rtcan_status_t rtcan_start(rtcan_handle_t* rtcan_h)
 {
+
  TX_THREAD* threads[2] = {&rtcan_h->tx_thread, &rtcan_h->rx_thread};
 
  for (uint32_t i = 0; i < 2; i++)
@@ -566,6 +555,51 @@ rtcan_status_t rtcan_subscribe(rtcan_handle_t* rtcan_h,
  }
  }
 
+ /* Add subscriber's CAN ID to CAN filter ID List */
+
+ int bank_number = rtcan_h->subscriber_number / NUM_IDS_PER_FILTER + 1; // Calculate the current filter bank number
+
+ /* We need to store 4 consecutive can_ids to setup filter bank. 
+ Otherwise, it overwrites the previous filter configuration deleting previous can_ids */
+
+ int k = rtcan_h->subscriber_number % NUM_IDS_PER_FILTER ; //Calculate index of element in can_ids table
+ rtcan_h->can_ids[k] = can_id;
+
+ rtcan_h->subscriber_number++; // Increment subscriber counter
+ ADD_ERROR_IF(bank_number > NUM_FILTERS, RTCAN_ERROR_INIT, rtcan_h);
+
+ if (no_errors(rtcan_h))
+ {
+ CAN_FilterTypeDef filter;
+ filter.FilterActivation = ENABLE;
+ filter.FilterMode = CAN_FILTERMODE_IDLIST;
+ filter.FilterScale = CAN_FILTERSCALE_16BIT; 
+
+ /* Configure Filter IDs for each filter bank */
+
+ filter.FilterIdHigh = rtcan_h->can_ids[0] << 5U;
+ filter.FilterIdLow = rtcan_h->can_ids[1] << 5U;
+ filter.FilterMaskIdHigh = rtcan_h->can_ids[2] << 5U;
+ filter.FilterMaskIdLow = rtcan_h->can_ids[3] << 5U;
+ filter.FilterBank = bank_number;
+
+ /* Alternate between FIFO0 and FIFO1 to share the load evenly */
+ if(bank_number % 2)
+ {
+ filter.FilterFIFOAssignment = CAN_FILTER_FIFO1; 
+ }
+ else 
+ {
+ filter.FilterFIFOAssignment = CAN_FILTER_FIFO0; 
+ }
+
+ HAL_StatusTypeDef hal_status = HAL_CAN_ConfigFilter(rtcan_h->hcan, 
+ &filter);
+
+ ADD_ERROR_IF(hal_status != HAL_OK, RTCAN_ERROR_INIT, rtcan_h);
+
+ }
+
  return create_status(rtcan_h);
 }