It extends the protocol to receive the adapter CAN state changes
(warning, busoff, etc.) and forward them to the netdev upper levels.
Signed-off-by: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx>
---
Changes in v2:
- Continue error handling even if no skb can be allocated.
drivers/net/can/slcan/slcan-core.c | 66 ++++++++++++++++++++++++++++++
1 file changed, 66 insertions(+)
diff --git a/drivers/net/can/slcan/slcan-core.c b/drivers/net/can/slcan/slcan-core.c
index aba42e284274..22a261f2477c 100644
--- a/drivers/net/can/slcan/slcan-core.c
+++ b/drivers/net/can/slcan/slcan-core.c
@@ -78,6 +78,9 @@ 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
struct slcan {
struct can_priv can;
@@ -170,6 +173,67 @@ int slcan_enable_err_rst_on_open(struct net_device *ndev, bool on)
* STANDARD SLCAN DECAPSULATION *
************************************************************************/
+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;
+
+ if (*cmd != 's')
+ return;
+
+ cmd += SLC_CMD_LEN;
+ switch (*cmd) {
+ 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 'f':
+ state = CAN_STATE_BUS_OFF;
+ break;
+ default:
+ return;
+ }
+
+ if (state == sl->can.state)
+ return;
+
+ cmd += SLC_STATE_BE_RXCNT_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;
+ }
+
+ tx_state = txerr >= rxerr ? state : 0;
+ rx_state = txerr <= rxerr ? state : 0;
+ can_change_state(dev, skb ? cf : NULL, tx_state, rx_state);
+
+ if (state == CAN_STATE_BUS_OFF)
+ can_bus_off(dev);
+
+ if (skb)
+ netif_rx(skb);
+}
+
static void slc_bump_err(struct slcan *sl)
{
struct net_device *dev = sl->dev;
@@ -372,6 +436,8 @@ 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;
}
--
2.32.0
