1*4882a593Smuzhiyun.. SPDX-License-Identifier: GPL-2.0 2*4882a593Smuzhiyun 3*4882a593Smuzhiyun============================================== 4*4882a593SmuzhiyunNetdev private dataroom for 6lowpan interfaces 5*4882a593Smuzhiyun============================================== 6*4882a593Smuzhiyun 7*4882a593SmuzhiyunAll 6lowpan able net devices, means all interfaces with ARPHRD_6LOWPAN, 8*4882a593Smuzhiyunmust have "struct lowpan_priv" placed at beginning of netdev_priv. 9*4882a593Smuzhiyun 10*4882a593SmuzhiyunThe priv_size of each interface should be calculate by:: 11*4882a593Smuzhiyun 12*4882a593Smuzhiyun dev->priv_size = LOWPAN_PRIV_SIZE(LL_6LOWPAN_PRIV_DATA); 13*4882a593Smuzhiyun 14*4882a593SmuzhiyunWhere LL_PRIV_6LOWPAN_DATA is sizeof linklayer 6lowpan private data struct. 15*4882a593SmuzhiyunTo access the LL_PRIV_6LOWPAN_DATA structure you can cast:: 16*4882a593Smuzhiyun 17*4882a593Smuzhiyun lowpan_priv(dev)-priv; 18*4882a593Smuzhiyun 19*4882a593Smuzhiyunto your LL_6LOWPAN_PRIV_DATA structure. 20*4882a593Smuzhiyun 21*4882a593SmuzhiyunBefore registering the lowpan netdev interface you must run:: 22*4882a593Smuzhiyun 23*4882a593Smuzhiyun lowpan_netdev_setup(dev, LOWPAN_LLTYPE_FOOBAR); 24*4882a593Smuzhiyun 25*4882a593Smuzhiyunwheres LOWPAN_LLTYPE_FOOBAR is a define for your 6LoWPAN linklayer type of 26*4882a593Smuzhiyunenum lowpan_lltypes. 27*4882a593Smuzhiyun 28*4882a593SmuzhiyunExample to evaluate the private usually you can do:: 29*4882a593Smuzhiyun 30*4882a593Smuzhiyun static inline struct lowpan_priv_foobar * 31*4882a593Smuzhiyun lowpan_foobar_priv(struct net_device *dev) 32*4882a593Smuzhiyun { 33*4882a593Smuzhiyun return (struct lowpan_priv_foobar *)lowpan_priv(dev)->priv; 34*4882a593Smuzhiyun } 35*4882a593Smuzhiyun 36*4882a593Smuzhiyun switch (dev->type) { 37*4882a593Smuzhiyun case ARPHRD_6LOWPAN: 38*4882a593Smuzhiyun lowpan_priv = lowpan_priv(dev); 39*4882a593Smuzhiyun /* do great stuff which is ARPHRD_6LOWPAN related */ 40*4882a593Smuzhiyun switch (lowpan_priv->lltype) { 41*4882a593Smuzhiyun case LOWPAN_LLTYPE_FOOBAR: 42*4882a593Smuzhiyun /* do 802.15.4 6LoWPAN handling here */ 43*4882a593Smuzhiyun lowpan_foobar_priv(dev)->bar = foo; 44*4882a593Smuzhiyun break; 45*4882a593Smuzhiyun ... 46*4882a593Smuzhiyun } 47*4882a593Smuzhiyun break; 48*4882a593Smuzhiyun ... 49*4882a593Smuzhiyun } 50*4882a593Smuzhiyun 51*4882a593SmuzhiyunIn case of generic 6lowpan branch ("net/6lowpan") you can remove the check 52*4882a593Smuzhiyunon ARPHRD_6LOWPAN, because you can be sure that these function are called 53*4882a593Smuzhiyunby ARPHRD_6LOWPAN interfaces. 54