Netfilter hook on the bridge not getting called

I am adding a hook function on a bridge.The question is: when in nf_hook_ops struct I use pf value like 7 (defined in PF_BRIDGE) then it DOESN'T work:

static struct nf_hook_ops nfho;nfho.hook = hook_func;nfho.owner = THIS_MODULE;nfho.hooknum = NF_IP_PRE_ROUTINGnfho.pf = PF_BRIDGE; // 7nfho.priority = INT_MAX;int rc = nf_register_hook(&nfho);

But if I use:

nfho.pf = 0x7000000;

Then it works without problems.

Linux version is 3.4.11 (Big-endian) and pf for this case should be int32 (not u_int8_t).

Does it depend on the Linux version? And how to detect which value to use (7 or 0x7000000)? Should I use something like htonl() or ntohl() for Big- and Little-endian machines?

Thank you in advance for any help!