Re: [PATCH V5 1/1] can: Add support for esd CAN PCIe/402 card

[Andri Yngvason <andri.yngvason@marel.com>]

Quoting Thomas Körper (2015-03-16 12:15:13)
[...]
> +static void
> +handle_core_msg_errstatechange(struct acc_core *core,
> +                              const struct acc_bmmsg_errstatechange *msg)
> +{
> +       struct acc_net_priv *priv = netdev_priv(core->net_dev);
> +       struct net_device_stats *stats = &core->net_dev->stats;
> +       struct can_frame *cf;
> +       struct sk_buff *skb;
> +       int is_busoff;
> +       int is_passive;
> +       int is_warning;
> +       u8 txerr;
> +       u8 rxerr;
> +
> +       txerr = (u8)(msg->reg_status >> 8);
> +       rxerr = (u8)msg->reg_status;
> +       is_warning = (msg->reg_status & ACC_REG_STATUS_MASK_STATUS_ES) != 0;
> +       is_passive = (msg->reg_status & ACC_REG_STATUS_MASK_STATUS_EP) != 0;
> +       is_busoff = (msg->reg_status & ACC_REG_STATUS_MASK_STATUS_BS) != 0;
> +
> +       skb = alloc_can_err_skb(core->net_dev, &cf);
> +       if (skb) {
> +               if (is_busoff) {
> +                       priv->can.state = CAN_STATE_BUS_OFF;
> +                       /* bus-offs counted by can_bus_off() */
> +                       cf->can_id |= CAN_ERR_BUSOFF;
> +               } else if (is_passive) {
> +                       priv->can.state = CAN_STATE_ERROR_PASSIVE;
> +                       priv->can.can_stats.error_passive++;
> +                       cf->data[1] = (txerr > rxerr) ?
> +                                       CAN_ERR_CRTL_TX_PASSIVE :
> +                                       CAN_ERR_CRTL_RX_PASSIVE;
> +                       cf->can_id |= CAN_ERR_CRTL;
> +                       cf->data[6] = txerr;
> +                       cf->data[7] = rxerr;
> +               } else if (is_warning) {
> +                       priv->can.state = CAN_STATE_ERROR_WARNING;
> +                       priv->can.can_stats.error_warning++;
> +                       cf->data[1] = (txerr > rxerr) ?
> +                                       CAN_ERR_CRTL_TX_WARNING :
> +                                       CAN_ERR_CRTL_RX_WARNING;
> +                       cf->can_id |= CAN_ERR_CRTL;
> +                       cf->data[6] = txerr;
> +                       cf->data[7] = rxerr;
> +               } else {
> +                       priv->can.state = CAN_STATE_ERROR_ACTIVE;
> +                       /* restarts counted in dev.c */
>
There is now a back-to-error-active message available for use, so you can do
    cf->can_id = CAN_ERR_CRTL;
    cf->data[1] = CAN_ERROR_CRTL_ACTIVE.
However, you could shave off a few lines in this code by using
can_change_state().
>
> +               }
> +
> +               netif_rx(skb);
> +               stats->rx_packets++;
> +               stats->rx_bytes += cf->can_dlc;
> +       }
> +
> +       if (is_busoff) {
> +               acc_write32(core, ACC_CORE_OF_TX_ABORT_MASK, 0xffff);
> +               can_bus_off(core->net_dev);
> +       }
> +}
> +
[...]

can_change_state() is now used in mscan, flexcan, sja1000, kvaser and peak.
Those drivers should provide sufficent examples for you to learn how to use the
function.

Best regards,
Andri Yngvason