2015-04-29 15:41:30

by Jeppe Ledet-Pedersen

[permalink] [raw]
Subject: [PATCH] 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 <[email protected]>
Acked-by: Kedareswara rao Appana <[email protected]>
---
drivers/net/can/xilinx_can.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/net/can/xilinx_can.c b/drivers/net/can/xilinx_can.c
index 6c67643..0b27769 100644
--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -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]);
--
2.1.0


2015-05-01 08:20:53

by Marc Kleine-Budde

[permalink] [raw]
Subject: Re: [PATCH] net: can: xilinx_can: fix extended frame handling

On 04/29/2015 05:05 PM, Jeppe Ledet-Pedersen wrote:
> 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 <[email protected]>
> Acked-by: Kedareswara rao Appana <[email protected]>

Applied to can. Added stable on Cc.

Thanks,
Marc

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