can: netlink support for bus-error reporting and counters

This patch makes the bus-error reporting configurable and allows to
retrieve the CAN TX and RX bus error counters via netlink interface.
I have added support for the SJA1000. The TX and RX bus error counters
are also copied to the data fields 6..7 of error messages when state
changes are reported.

Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index f08f1202ff003cbe4f1854e2e2ebea44779118dd..904aa369f80e13c0d02a664fa23aee2019246b8d 100644 (file)
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -574,6 +574,7 @@ static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
        [IFLA_CAN_BITTIMING_CONST]
                                = { .len = sizeof(struct can_bittiming_const) },
        [IFLA_CAN_CLOCK]        = { .len = sizeof(struct can_clock) },
+       [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) },
 };
 
 static int can_changelink(struct net_device *dev,
@@ -649,6 +650,8 @@ static size_t can_get_size(const struct net_device *dev)
        size += nla_total_size(sizeof(u32));  /* IFLA_CAN_RESTART_MS */
        size += sizeof(struct can_bittiming); /* IFLA_CAN_BITTIMING */
        size += sizeof(struct can_clock);     /* IFLA_CAN_CLOCK */
+       if (priv->do_get_berr_counter)        /* IFLA_CAN_BERR_COUNTER */
+               size += sizeof(struct can_berr_counter);
        if (priv->bittiming_const)            /* IFLA_CAN_BITTIMING_CONST */
                size += sizeof(struct can_bittiming_const);
 
@@ -659,6 +662,7 @@ static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
 {
        struct can_priv *priv = netdev_priv(dev);
        struct can_ctrlmode cm = {.flags = priv->ctrlmode};
+       struct can_berr_counter bec;
        enum can_state state = priv->state;
 
        if (priv->do_get_state)
@@ -669,6 +673,8 @@ static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
        NLA_PUT(skb, IFLA_CAN_BITTIMING,
                sizeof(priv->bittiming), &priv->bittiming);
        NLA_PUT(skb, IFLA_CAN_CLOCK, sizeof(cm), &priv->clock);
+       if (priv->do_get_berr_counter && !priv->do_get_berr_counter(dev, &bec))
+               NLA_PUT(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec);
        if (priv->bittiming_const)
                NLA_PUT(skb, IFLA_CAN_BITTIMING_CONST,
                        sizeof(*priv->bittiming_const), priv->bittiming_const);

diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c
index ace103a44833378aef5d8b5027bb4a1db79ce19f..145b1a731a53aa99f9c8c902df96bf8453c59796 100644 (file)
--- a/drivers/net/can/sja1000/sja1000.c
+++ b/drivers/net/can/sja1000/sja1000.c
@@ -130,8 +130,12 @@ static void set_normal_mode(struct net_device *dev)
                /* check reset bit */
                if ((status & MOD_RM) == 0) {
                        priv->can.state = CAN_STATE_ERROR_ACTIVE;
-                       /* enable all interrupts */
-                       priv->write_reg(priv, REG_IER, IRQ_ALL);
+                       /* enable interrupts */
+                       if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
+                               priv->write_reg(priv, REG_IER, IRQ_ALL);
+                       else
+                               priv->write_reg(priv, REG_IER,
+                                               IRQ_ALL & ~IRQ_BEI);
                        return;
                }
 
@@ -203,6 +207,17 @@ static int sja1000_set_bittiming(struct net_device *dev)
        return 0;
 }
 
+static int sja1000_get_berr_counter(const struct net_device *dev,
+                                   struct can_berr_counter *bec)
+{
+       struct sja1000_priv *priv = netdev_priv(dev);
+
+       bec->txerr = priv->read_reg(priv, REG_TXERR);
+       bec->rxerr = priv->read_reg(priv, REG_RXERR);
+
+       return 0;
+}
+
 /*
  * initialize SJA1000 chip:
  *   - reset chip
@@ -437,6 +452,8 @@ static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
                                CAN_ERR_CRTL_TX_PASSIVE :
                                CAN_ERR_CRTL_RX_PASSIVE;
                }
+               cf->data[6] = txerr;
+               cf->data[7] = rxerr;
        }
 
        priv->can.state = state;
@@ -567,7 +584,9 @@ struct net_device *alloc_sja1000dev(int sizeof_priv)
        priv->can.bittiming_const = &sja1000_bittiming_const;
        priv->can.do_set_bittiming = sja1000_set_bittiming;
        priv->can.do_set_mode = sja1000_set_mode;
-       priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
+       priv->can.do_get_berr_counter = sja1000_get_berr_counter;
+       priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES |
+               CAN_CTRLMODE_BERR_REPORTING;
 
        if (sizeof_priv)
                priv->priv = (void *)priv + sizeof(struct sja1000_priv);

diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index c8c660a79f907657af7349fd78d0eb21099a88a0..6e5a7f00223d28afc366d189fa2e9df1ad261cf1 100644 (file)
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -47,6 +47,8 @@ struct can_priv {
        int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
        int (*do_get_state)(const struct net_device *dev,
                            enum can_state *state);
+       int (*do_get_berr_counter)(const struct net_device *dev,
+                                  struct can_berr_counter *bec);
 
        unsigned int echo_skb_max;
        struct sk_buff **echo_skb;

diff --git a/include/linux/can/netlink.h b/include/linux/can/netlink.h
index c818335fbb132e6d2d7a82fd6638702c305a5f22..3250de935e1a95522c48c4f48e9f753dc37fc72e 100644 (file)
--- a/include/linux/can/netlink.h
+++ b/include/linux/can/netlink.h
@@ -69,6 +69,14 @@ enum can_state {
        CAN_STATE_MAX
 };
 
+/*
+ * CAN bus error counters
+ */
+struct can_berr_counter {
+       __u16 txerr;
+       __u16 rxerr;
+};
+
 /*
  * CAN controller mode
  */
@@ -77,10 +85,11 @@ struct can_ctrlmode {
        __u32 flags;
 };
 
-#define CAN_CTRLMODE_LOOPBACK  0x1     /* Loopback mode */
-#define CAN_CTRLMODE_LISTENONLY        0x2     /* Listen-only mode */
-#define CAN_CTRLMODE_3_SAMPLES 0x4     /* Triple sampling mode */
-#define CAN_CTRLMODE_ONE_SHOT  0x8     /* One-Shot mode */
+#define CAN_CTRLMODE_LOOPBACK          0x01    /* Loopback mode */
+#define CAN_CTRLMODE_LISTENONLY                0x02    /* Listen-only mode */
+#define CAN_CTRLMODE_3_SAMPLES         0x04    /* Triple sampling mode */
+#define CAN_CTRLMODE_ONE_SHOT          0x08    /* One-Shot mode */
+#define CAN_CTRLMODE_BERR_REPORTING    0x10    /* Bus-error reporting */
 
 /*
  * CAN device statistics
@@ -106,6 +115,7 @@ enum {
        IFLA_CAN_CTRLMODE,
        IFLA_CAN_RESTART_MS,
        IFLA_CAN_RESTART,
+       IFLA_CAN_BERR_COUNTER,
        __IFLA_CAN_MAX
 };