Hi,

I don't know if someone is still maintaining the Hynix CCAN driver in
SocketCAN SVN, but I will appreciate if any one of the developers here, can
help me out.

For the past 1 week, I have worked on developing a CCAN driver for my client
on linux 2.6.27, which takes most of the clues from the Hynix CCAN driver in
SocketCAN trunk. I have since made changes to align my driver with the new
`sja1000` like implementation.

Similar to Hynix, my SOC has 2 CAN IPs and I intend to use the same driver
to handle both the IPs.

Gud news is that when I use CAN-IP1 as a Tx (and send frames using
`cansend`) and CAN-IP2 as a Rx (and receive frames using `candump`), if I
transmit only a single CAN Frame, I am successfully able to see proper Rx at
CAN-IP2.

Now, the only issue remains that when send multiple CAN frames using the
`cansend` utility (a older version picked up from
`http://www.pengutronix.de/software/socket-can/download/canutils/v3.0/`), my
`candump` complaints that it has received a REMOTE REQUEST, whereas I do
have not used `-r` option with cansend to send remote frames.

When I look at Hynix driver in SVN, I see the following check:

*drivers/can/ccan.c*

static int ccan_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct ccan_priv *priv = netdev_priv(dev);
        struct can_frame *frame = (struct can_frame *)skb->data;

        spin_lock_irq(&priv->can.irq_lock);

        ccan_write_object(dev, 0, frame, priv->tx_object);
#ifdef CCAN_DEBUG
        priv->bufstat[priv->tx_object]++;
#endif
        priv->tx_object++;
        if (priv->tx_object > 5)
                netif_stop_queue(dev);

..
}

Now, what is the significance of stopping the `netif_queue` when the
priv->tx_object becomes 5.
This must be a limitation seen by the developer of this driver in the CCAN
IP in Hynix.

This may help me in understanding the issue I am having with my CCAN.

Thanks,
Bhupesh 

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