[mirror_ubuntu-bionic-kernel.git] / Documentation / networking / 6lowpan.txt


Netdev private dataroom for 6lowpan interfaces:

All 6lowpan able net devices, means all interfaces with ARPHRD_6LOWPAN,
must have "struct lowpan_priv" placed at beginning of netdev_priv.

The priv_size of each interface should be calculate by:

 dev->priv_size = LOWPAN_PRIV_SIZE(LL_6LOWPAN_PRIV_DATA);

Where LL_PRIV_6LOWPAN_DATA is sizeof linklayer 6lowpan private data struct.
To access the LL_PRIV_6LOWPAN_DATA structure you can cast:

 lowpan_priv(dev)-priv;

to your LL_6LOWPAN_PRIV_DATA structure.

Before registering the lowpan netdev interface you must run:

 lowpan_netdev_setup(dev, LOWPAN_LLTYPE_FOOBAR);

wheres LOWPAN_LLTYPE_FOOBAR is a define for your 6LoWPAN linklayer type of
enum lowpan_lltypes.

Example to evaluate the private usually you can do:

static inline sturct lowpan_priv_foobar *
lowpan_foobar_priv(struct net_device *dev)
{
	return (sturct lowpan_priv_foobar *)lowpan_priv(dev)->priv;
}

switch (dev->type) {
case ARPHRD_6LOWPAN:
	lowpan_priv = lowpan_priv(dev);
	/* do great stuff which is ARPHRD_6LOWPAN related */
	switch (lowpan_priv->lltype) {
	case LOWPAN_LLTYPE_FOOBAR:
		/* do 802.15.4 6LoWPAN handling here */
		lowpan_foobar_priv(dev)->bar = foo;
		break;
	...
	}
	break;
...
}

In case of generic 6lowpan branch ("net/6lowpan") you can remove the check
on ARPHRD_6LOWPAN, because you can be sure that these function are called
by ARPHRD_6LOWPAN interfaces.
Commit	Line	Data
ea9eb698 AA	1
	2	Netdev private dataroom for 6lowpan interfaces:
	3
	4	All 6lowpan able net devices, means all interfaces with ARPHRD_6LOWPAN,
	5	must have "struct lowpan_priv" placed at beginning of netdev_priv.
	6
	7	The priv_size of each interface should be calculate by:
	8
	9	dev->priv_size = LOWPAN_PRIV_SIZE(LL_6LOWPAN_PRIV_DATA);
	10
	11	Where LL_PRIV_6LOWPAN_DATA is sizeof linklayer 6lowpan private data struct.
	12	To access the LL_PRIV_6LOWPAN_DATA structure you can cast:
	13
	14	lowpan_priv(dev)-priv;
	15
	16	to your LL_6LOWPAN_PRIV_DATA structure.
	17
	18	Before registering the lowpan netdev interface you must run:
	19
	20	lowpan_netdev_setup(dev, LOWPAN_LLTYPE_FOOBAR);
	21
	22	wheres LOWPAN_LLTYPE_FOOBAR is a define for your 6LoWPAN linklayer type of
	23	enum lowpan_lltypes.
	24
	25	Example to evaluate the private usually you can do:
	26
	27	static inline sturct lowpan_priv_foobar *
	28	lowpan_foobar_priv(struct net_device *dev)
	29	{
	30	return (sturct lowpan_priv_foobar *)lowpan_priv(dev)->priv;
	31	}
	32
	33	switch (dev->type) {
	34	case ARPHRD_6LOWPAN:
	35	lowpan_priv = lowpan_priv(dev);
	36	/* do great stuff which is ARPHRD_6LOWPAN related */
	37	switch (lowpan_priv->lltype) {
	38	case LOWPAN_LLTYPE_FOOBAR:
	39	/* do 802.15.4 6LoWPAN handling here */
	40	lowpan_foobar_priv(dev)->bar = foo;
	41	break;
	42	...
	43	}
	44	break;
	45	...
	46	}
	47
	48	In case of generic 6lowpan branch ("net/6lowpan") you can remove the check
	49	on ARPHRD_6LOWPAN, because you can be sure that these function are called
	50	by ARPHRD_6LOWPAN interfaces.