On Thu, 9 May 2024, Christoph Fritz wrote:
> The CAN Broadcast Manager now has the capability to dispatch CANFD
> frames marked with the id LINBUS_RXOFFLOAD_ID.
>
> Introduce functionality to interpret these specific frames, enabling the
> configuration of RX offloading within the LIN driver.
>
> Signed-off-by: Christoph Fritz <christoph.fritz@xxxxxxxxx>
> ---
> drivers/net/can/lin.c | 29 +++++++++++++++++++++++++++++
> 1 file changed, 29 insertions(+)
>
> diff --git a/drivers/net/can/lin.c b/drivers/net/can/lin.c
> index a22768c17e3f8..f77abd7d7d21c 100644
> --- a/drivers/net/can/lin.c
> +++ b/drivers/net/can/lin.c
> @@ -185,6 +185,27 @@ static const struct attribute_group lin_sysfs_group = {
> .attrs = lin_sysfs_attrs,
> };
>
> +static int lin_setup_rxoffload(struct lin_device *ldev,
> + struct canfd_frame *cfd)
> +{
> + struct lin_responder_answer answ;
> +
> + if (!(cfd->flags & CANFD_FDF))
> + return -EINVAL;
> +
> + BUILD_BUG_ON(sizeof(answ) > sizeof(cfd->data));
> + memcpy(&answ, cfd->data, sizeof(answ));
> +
> + answ.lf.checksum_mode = (cfd->can_id & LIN_ENHANCED_CKSUM_FLAG) ?
> + LINBUS_ENHANCED : LINBUS_CLASSIC;
> +
> + if (answ.lf.lin_id > LIN_ID_MASK ||
> + answ.event_associated_id > LIN_ID_MASK)
> + return -EINVAL;
These can be reverse so that error check occur before the checksum_mode
assignment? It would feel more natural that way.
...Even better, if the error check could be done before the memcpy().
--
i.
> + return ldev->ldev_ops->update_responder_answer(ldev, &answ);
> +}
> +
> static void lin_tx_work_handler(struct work_struct *ws)
> {
> struct lin_device *ldev = container_of(ws, struct lin_device,
> @@ -197,6 +218,14 @@ static void lin_tx_work_handler(struct work_struct *ws)
> ldev->tx_busy = true;
>
> cfd = (struct canfd_frame *)ldev->tx_skb->data;
> +
> + if (cfd->can_id & LIN_RXOFFLOAD_DATA_FLAG) {
> + ret = lin_setup_rxoffload(ldev, cfd);
> + if (ret < 0)
> + netdev_err(ndev, "setting up rx failed %d\n", ret);
> + goto lin_tx_out;
> + }
> +
> lf.checksum_mode = (cfd->can_id & LIN_ENHANCED_CKSUM_FLAG) ?
> LINBUS_ENHANCED : LINBUS_CLASSIC;
> lf.lin_id = cfd->can_id & LIN_ID_MASK;
>
