[RFC PATCH v3 1/6] can: dev: add generic function can_update_bus_error_stats()

[Dario Binacchi]

The function aims to generalize the statistics update by centralizing
the related code, thus avoiding code duplication.

Signed-off-by: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx>

---

Changes in v3:
- Drop double assignement of "priv" variable.
- Check "dev" parameter is not NULL.

 drivers/net/can/dev/dev.c | 30 ++++++++++++++++++++++++++++++
 include/linux/can/dev.h   |  1 +
 2 files changed, 31 insertions(+)

diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c
index 6792c14fd7eb..4ad0698b0a74 100644
--- a/drivers/net/can/dev/dev.c
+++ b/drivers/net/can/dev/dev.c
@@ -16,6 +16,36 @@
 #include <linux/gpio/consumer.h>
 #include <linux/of.h>
 
+void can_update_bus_error_stats(struct net_device *dev, struct can_frame *cf)
+{
+	struct can_priv *priv;
+	bool rx_errors = false, tx_errors = false;
+
+	if (!dev || !cf || !(cf->can_id & (CAN_ERR_PROT | CAN_ERR_BUSERROR)))
+		return;
+
+	priv = netdev_priv(dev);
+	priv->can_stats.bus_error++;
+
+	if ((cf->can_id & CAN_ERR_ACK) && cf->data[3] == CAN_ERR_PROT_LOC_ACK)
+		tx_errors = true;
+	else if (cf->data[2] & (CAN_ERR_PROT_BIT1 | CAN_ERR_PROT_BIT0))
+		tx_errors = true;
+
+	if (cf->data[2] & (CAN_ERR_PROT_FORM | CAN_ERR_PROT_STUFF))
+		rx_errors = true;
+	else if ((cf->data[2] & CAN_ERR_PROT_BIT) &&
+		 (cf->data[3] == CAN_ERR_PROT_LOC_CRC_SEQ))
+		rx_errors = true;
+
+	if (rx_errors)
+		dev->stats.rx_errors++;
+
+	if (tx_errors)
+		dev->stats.tx_errors++;
+}
+EXPORT_SYMBOL_GPL(can_update_bus_error_stats);
+
 static void can_update_state_error_stats(struct net_device *dev,
 					 enum can_state new_state)
 {
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index 23492213ea35..0977656b366d 100644
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -201,6 +201,7 @@ void can_state_get_by_berr_counter(const struct net_device *dev,
 				   enum can_state *rx_state);
 void can_change_state(struct net_device *dev, struct can_frame *cf,
 		      enum can_state tx_state, enum can_state rx_state);
+void can_update_bus_error_stats(struct net_device *dev, struct can_frame *cf);
 
 #ifdef CONFIG_OF
 void of_can_transceiver(struct net_device *dev);
-- 
2.43.0