diff --git a/drivers/net/can/cc770/cc770.c b/drivers/net/can/cc770/cc770.c index 9fed163262e0..2743d82d4424 100644 --- a/drivers/net/can/cc770/cc770.c +++ b/drivers/net/can/cc770/cc770.c @@ -390,37 +390,23 @@ static int cc770_get_berr_counter(const struct net_device *dev, return 0; } -static netdev_tx_t cc770_start_xmit(struct sk_buff *skb, struct net_device *dev) +static void cc770_tx(struct net_device *dev, int mo) { struct cc770_priv *priv = netdev_priv(dev); - struct net_device_stats *stats = &dev->stats; - struct can_frame *cf = (struct can_frame *)skb->data; - unsigned int mo = obj2msgobj(CC770_OBJ_TX); + struct can_frame *cf = (struct can_frame *)priv->tx_skb->data; u8 dlc, rtr; u32 id; int i; - if (can_dropped_invalid_skb(dev, skb)) - return NETDEV_TX_OK; - - if ((cc770_read_reg(priv, - msgobj[mo].ctrl1) & TXRQST_UNC) == TXRQST_SET) { - netdev_err(dev, "TX register is still occupied!\n"); - return NETDEV_TX_BUSY; - } - - netif_stop_queue(dev); - dlc = cf->can_dlc; id = cf->can_id; - if (cf->can_id & CAN_RTR_FLAG) - rtr = 0; - else - rtr = MSGCFG_DIR; + rtr = cf->can_id & CAN_RTR_FLAG ? 0 : MSGCFG_DIR; + + cc770_write_reg(priv, msgobj[mo].ctrl0, + MSGVAL_RES | TXIE_RES | RXIE_RES | INTPND_RES); cc770_write_reg(priv, msgobj[mo].ctrl1, RMTPND_RES | TXRQST_RES | CPUUPD_SET | NEWDAT_RES); - cc770_write_reg(priv, msgobj[mo].ctrl0, - MSGVAL_SET | TXIE_SET | RXIE_RES | INTPND_RES); + if (id & CAN_EFF_FLAG) { id &= CAN_EFF_MASK; cc770_write_reg(priv, msgobj[mo].config, @@ -439,13 +425,30 @@ static netdev_tx_t cc770_start_xmit(struct sk_buff *skb, struct net_device *dev) for (i = 0; i < dlc; i++) cc770_write_reg(priv, msgobj[mo].data[i], cf->data[i]); - /* Store echo skb before starting the transfer */ - can_put_echo_skb(skb, dev, 0); - cc770_write_reg(priv, msgobj[mo].ctrl1, - RMTPND_RES | TXRQST_SET | CPUUPD_RES | NEWDAT_UNC); + RMTPND_UNC | TXRQST_SET | CPUUPD_RES | NEWDAT_UNC); + cc770_write_reg(priv, msgobj[mo].ctrl0, + MSGVAL_SET | TXIE_SET | RXIE_SET | INTPND_UNC); +} - stats->tx_bytes += dlc; +static netdev_tx_t cc770_start_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct cc770_priv *priv = netdev_priv(dev); + unsigned int mo = obj2msgobj(CC770_OBJ_TX); + + if (can_dropped_invalid_skb(dev, skb)) + return NETDEV_TX_OK; + + netif_stop_queue(dev); + + if ((cc770_read_reg(priv, + msgobj[mo].ctrl1) & TXRQST_UNC) == TXRQST_SET) { + netdev_err(dev, "TX register is still occupied!\n"); + return NETDEV_TX_BUSY; + } + + priv->tx_skb = skb; + cc770_tx(dev, mo); return NETDEV_TX_OK; } @@ -671,13 +674,47 @@ static void cc770_tx_interrupt(struct net_device *dev, unsigned int o) struct cc770_priv *priv = netdev_priv(dev); struct net_device_stats *stats = &dev->stats; unsigned int mo = obj2msgobj(o); + struct can_frame *cf; + u8 ctrl1; + + ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1); - /* Nothing more to send, switch off interrupts */ cc770_write_reg(priv, msgobj[mo].ctrl0, MSGVAL_RES | TXIE_RES | RXIE_RES | INTPND_RES); + cc770_write_reg(priv, msgobj[mo].ctrl1, + RMTPND_RES | TXRQST_RES | MSGLST_RES | NEWDAT_RES); - stats->tx_packets++; + if (unlikely(!priv->tx_skb)) { + netdev_err(dev, "missing tx skb in tx interrupt\n"); + return; + } + + if (unlikely(ctrl1 & MSGLST_SET)) { + stats->rx_over_errors++; + stats->rx_errors++; + } + + /* When the CC770 is sending an RTR message and it receives a regular + * message that matches the id of the RTR message, it will overwrite the + * outgoing message in the TX register. When this happens we must + * process the received message and try to transmit the outgoing skb + * again. + */ + if (unlikely(ctrl1 & NEWDAT_SET)) { + cc770_rx(dev, mo, ctrl1); + cc770_tx(dev, mo); + return; + } + + can_put_echo_skb(priv->tx_skb, dev, 0); can_get_echo_skb(dev, 0); + + cf = (struct can_frame *)priv->tx_skb->data; + stats->tx_bytes += cf->can_dlc; + stats->tx_packets++; + + priv->tx_skb = NULL; + netif_wake_queue(dev); } @@ -789,6 +826,7 @@ struct net_device *alloc_cc770dev(int sizeof_priv) priv->can.do_set_bittiming = cc770_set_bittiming; priv->can.do_set_mode = cc770_set_mode; priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES; + priv->tx_skb = NULL; memcpy(priv->obj_flags, cc770_obj_flags, sizeof(cc770_obj_flags)); diff --git a/drivers/net/can/cc770/cc770.h b/drivers/net/can/cc770/cc770.h index a1739db98d91..95752e1d1283 100644 --- a/drivers/net/can/cc770/cc770.h +++ b/drivers/net/can/cc770/cc770.h @@ -193,6 +193,8 @@ struct cc770_priv { u8 cpu_interface; /* CPU interface register */ u8 clkout; /* Clock out register */ u8 bus_config; /* Bus conffiguration register */ + + struct sk_buff *tx_skb; }; struct net_device *alloc_cc770dev(int sizeof_priv);