On 22/03/2020 19.03, Robert Barrows wrote:
Thank you for all the direction Oliver, I think I am on the correct path,
but now have can_send returning with a "-1" (ERESTART). I used raw_sendmsg
as a template for this and cut out (hopefully) unneeded code, but I am
concerned I cut out something I needed. Would you mind taking another look?
Thanks.
int SendCanTime(struct timespec *tsCurrentTime) {
struct sk_buff *skb;
struct can_frame *frame = kmalloc(sizeof (struct can_frame), GFP_KERNEL);
struct net_device *dev;
int err = 0;
int thetime = tsCurrentTime->tv_sec;
// Set up can frame
frame->can_id = 0x00050F93 | CAN_EFF_FLAG;
frame->can_dlc = 6;
frame->data[0] = 0x00;
frame->data[1] = 0x02;
memcpy(frame->data+2, &thetime, sizeof(int));
// Find the netdevice named can0
read_lock(&dev_base_lock);
dev = first_net_device(&init_net);
while (!strcmp(dev->name, "can0")) {
printk(KERN_INFO "found [%s]\n", dev->name);
dev = next_net_device(dev);
}
read_unlock(&dev_base_lock);
What does this return when you don't have can0 in the system??
You should use
__dev_get_by_name()
here.
https://elixir.bootlin.com/linux/latest/source/net/core/dev.c#L762
And check for success :-)
if (!dev)
return -ENXIO;
// Create skb
skb = alloc_can_skb(dev, &frame);
if (!skb)
goto put_dev;
skb->dev = dev;
err = can_send(skb, 0);
dev_put(dev);
if (err)
goto send_failed;
return 0;
//kfree_skb(skb);
put_dev:
dev_put(dev);
send_failed:
return err;
}
^
