From: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx> It extends the protocol to receive the adapter CAN state changes (warning, busoff, etc.) and forward them to the netdev upper levels. Link: https://lore.kernel.org/all/20220628163137.413025-13-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 | 74 +++++++++++++++++++++++++++++- 1 file changed, 73 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/slcan/slcan-core.c b/drivers/net/can/slcan/slcan-core.c index 4269b2267be2..54d29a410ad5 100644 --- a/drivers/net/can/slcan/slcan-core.c +++ b/drivers/net/can/slcan/slcan-core.c @@ -78,7 +78,11 @@ MODULE_PARM_DESC(maxdev, "Maximum number of slcan interfaces"); #define SLC_CMD_LEN 1 #define SLC_SFF_ID_LEN 3 #define SLC_EFF_ID_LEN 8 - +#define SLC_STATE_LEN 1 +#define SLC_STATE_BE_RXCNT_LEN 3 +#define SLC_STATE_BE_TXCNT_LEN 3 +#define SLC_STATE_FRAME_LEN (1 + SLC_CMD_LEN + SLC_STATE_BE_RXCNT_LEN + \ + SLC_STATE_BE_TXCNT_LEN) struct slcan { struct can_priv can; int magic; @@ -254,6 +258,72 @@ static void slc_bump_frame(struct slcan *sl) dev_kfree_skb(skb); } +/* A change state frame must contain state info and receive and transmit + * error counters. + * + * Examples: + * + * sb256256 : state bus-off: rx counter 256, tx counter 256 + * sa057033 : state active, rx counter 57, tx counter 33 + */ +static void slc_bump_state(struct slcan *sl) +{ + struct net_device *dev = sl->dev; + struct sk_buff *skb; + struct can_frame *cf; + char *cmd = sl->rbuff; + u32 rxerr, txerr; + enum can_state state, rx_state, tx_state; + + switch (cmd[1]) { + case 'a': + state = CAN_STATE_ERROR_ACTIVE; + break; + case 'w': + state = CAN_STATE_ERROR_WARNING; + break; + case 'p': + state = CAN_STATE_ERROR_PASSIVE; + break; + case 'b': + state = CAN_STATE_BUS_OFF; + break; + default: + return; + } + + if (state == sl->can.state || sl->rcount < SLC_STATE_FRAME_LEN) + return; + + cmd += SLC_STATE_BE_RXCNT_LEN + SLC_CMD_LEN + 1; + cmd[SLC_STATE_BE_TXCNT_LEN] = 0; + if (kstrtou32(cmd, 10, &txerr)) + return; + + *cmd = 0; + cmd -= SLC_STATE_BE_RXCNT_LEN; + if (kstrtou32(cmd, 10, &rxerr)) + return; + + skb = alloc_can_err_skb(dev, &cf); + if (skb) { + cf->data[6] = txerr; + cf->data[7] = rxerr; + } else { + cf = NULL; + } + + tx_state = txerr >= rxerr ? state : 0; + rx_state = txerr <= rxerr ? state : 0; + can_change_state(dev, cf, tx_state, rx_state); + + if (state == CAN_STATE_BUS_OFF) + can_bus_off(dev); + + if (skb) + netif_rx(skb); +} + /* An error frame can contain more than one type of error. * * Examples: @@ -387,6 +457,8 @@ static void slc_bump(struct slcan *sl) return slc_bump_frame(sl); case 'e': return slc_bump_err(sl); + case 's': + return slc_bump_state(sl); default: return; } -- 2.35.1
