net: can: xilinx_can: fix extended frame handling

Using IDR_SRR in RXFIFO_ID to test for the presence of data is only
valid for standard frames. For extended frames the bit is always 1 and
IDR_RTR should be used instead. This patch switches the check to use
CAN_RTR_FLAG which is correctly set when reading the ID.

The patch also changes the DW1/DW2 to be read unconditionally, since
this is necessary to remove the frame from the RXFIFO.

Signed-off-by: Jeppe Ledet-Pedersen <jlp@gomspace.com>
Acked-by: Kedareswara rao Appana <appanad@xilinx.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Jeppe Ledet-Pedersen 2015-04-29 17:05:01 +02:00 committed by Marc Kleine-Budde
parent e813bb2b95
commit 5793affe8c

View File

@ -509,10 +509,11 @@ static int xcan_rx(struct net_device *ndev)
cf->can_id |= CAN_RTR_FLAG;
}
if (!(id_xcan & XCAN_IDR_SRR_MASK)) {
data[0] = priv->read_reg(priv, XCAN_RXFIFO_DW1_OFFSET);
data[1] = priv->read_reg(priv, XCAN_RXFIFO_DW2_OFFSET);
/* DW1/DW2 must always be read to remove message from RXFIFO */
data[0] = priv->read_reg(priv, XCAN_RXFIFO_DW1_OFFSET);
data[1] = priv->read_reg(priv, XCAN_RXFIFO_DW2_OFFSET);
if (!(cf->can_id & CAN_RTR_FLAG)) {
/* Change Xilinx CAN data format to socketCAN data format */
if (cf->can_dlc > 0)
*(__be32 *)(cf->data) = cpu_to_be32(data[0]);