From: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx> It extends the protocol to receive the adapter CAN communication errors and forward them to the netdev upper levels. Link: https://lore.kernel.org/all/20220628163137.413025-12-dario.binacchi@xxxxxxxxxxxxxxxxxxxx Signed-off-by: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> --- drivers/net/can/slcan/slcan-core.c | 140 ++++++++++++++++++++++++++++- 1 file changed, 139 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/slcan/slcan-core.c b/drivers/net/can/slcan/slcan-core.c index c1fd1e934d93..4269b2267be2 100644 --- a/drivers/net/can/slcan/slcan-core.c +++ b/drivers/net/can/slcan/slcan-core.c @@ -175,7 +175,7 @@ int slcan_enable_err_rst_on_open(struct net_device *ndev, bool on) ************************************************************************/ /* Send one completely decapsulated can_frame to the network layer */ -static void slc_bump(struct slcan *sl) +static void slc_bump_frame(struct slcan *sl) { struct sk_buff *skb; struct can_frame *cf; @@ -254,6 +254,144 @@ static void slc_bump(struct slcan *sl) dev_kfree_skb(skb); } +/* An error frame can contain more than one type of error. + * + * Examples: + * + * e1a : len 1, errors: ACK error + * e3bcO: len 3, errors: Bit0 error, CRC error, Tx overrun error + */ +static void slc_bump_err(struct slcan *sl) +{ + struct net_device *dev = sl->dev; + struct sk_buff *skb; + struct can_frame *cf; + char *cmd = sl->rbuff; + bool rx_errors = false, tx_errors = false, rx_over_errors = false; + int i, len; + + /* get len from sanitized ASCII value */ + len = cmd[1]; + if (len >= '0' && len < '9') + len -= '0'; + else + return; + + if ((len + SLC_CMD_LEN + 1) > sl->rcount) + return; + + skb = alloc_can_err_skb(dev, &cf); + + if (skb) + cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; + + cmd += SLC_CMD_LEN + 1; + for (i = 0; i < len; i++, cmd++) { + switch (*cmd) { + case 'a': + netdev_dbg(dev, "ACK error\n"); + tx_errors = true; + if (skb) { + cf->can_id |= CAN_ERR_ACK; + cf->data[3] = CAN_ERR_PROT_LOC_ACK; + } + + break; + case 'b': + netdev_dbg(dev, "Bit0 error\n"); + tx_errors = true; + if (skb) + cf->data[2] |= CAN_ERR_PROT_BIT0; + + break; + case 'B': + netdev_dbg(dev, "Bit1 error\n"); + tx_errors = true; + if (skb) + cf->data[2] |= CAN_ERR_PROT_BIT1; + + break; + case 'c': + netdev_dbg(dev, "CRC error\n"); + rx_errors = true; + if (skb) { + cf->data[2] |= CAN_ERR_PROT_BIT; + cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ; + } + + break; + case 'f': + netdev_dbg(dev, "Form Error\n"); + rx_errors = true; + if (skb) + cf->data[2] |= CAN_ERR_PROT_FORM; + + break; + case 'o': + netdev_dbg(dev, "Rx overrun error\n"); + rx_over_errors = true; + rx_errors = true; + if (skb) { + cf->can_id |= CAN_ERR_CRTL; + cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; + } + + break; + case 'O': + netdev_dbg(dev, "Tx overrun error\n"); + tx_errors = true; + if (skb) { + cf->can_id |= CAN_ERR_CRTL; + cf->data[1] = CAN_ERR_CRTL_TX_OVERFLOW; + } + + break; + case 's': + netdev_dbg(dev, "Stuff error\n"); + rx_errors = true; + if (skb) + cf->data[2] |= CAN_ERR_PROT_STUFF; + + break; + default: + if (skb) + dev_kfree_skb(skb); + + return; + } + } + + if (rx_errors) + dev->stats.rx_errors++; + + if (rx_over_errors) + dev->stats.rx_over_errors++; + + if (tx_errors) + dev->stats.tx_errors++; + + if (skb) + netif_rx(skb); +} + +static void slc_bump(struct slcan *sl) +{ + switch (sl->rbuff[0]) { + case 'r': + fallthrough; + case 't': + fallthrough; + case 'R': + fallthrough; + case 'T': + return slc_bump_frame(sl); + case 'e': + return slc_bump_err(sl); + default: + return; + } +} + /* parse tty input stream */ static void slcan_unesc(struct slcan *sl, unsigned char s) { -- 2.35.1
