/*
 * File: mhi_proto.c
 *
 * Copyright (C) 2011 Renesas Mobile Corporation. All rights reserved.
 *
 * Author: Petri Mattila <petri.to.mattila@renesasmobile.com>
 *
 * Modem-Host Interface (MHI) Protocol Family
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/if_mhi.h>
#include <linux/mhi.h>
#include <linux/l2mux.h>

#include <net/af_mhi.h>
#include <net/mhi/sock.h>
#include <net/mhi/dgram.h>
#include <net/mhi/raw.h>

#ifdef CONFIG_MHI_DEBUG
# define DPRINTK(...)    printk(KERN_DEBUG "AF_MHI: " __VA_ARGS__)
#else
# define DPRINTK(...)
#endif


/* Supported L2 protocols */
static __u8 mhi_protocols[MHI_L3_NPROTO] __read_mostly = { 0, };


/*** Functions ***/

int
mhi_protocol_registered(int protocol)
{
	if (protocol >= 0 && protocol < MHI_L3_NPROTO)
		return mhi_protocols[protocol];
	if (protocol == MHI_L3_ANY)
		return 1;

	return 0;
}
EXPORT_SYMBOL(mhi_protocol_registered);

int
mhi_register_protocol(int protocol)
{
	DPRINTK("mhi_register_protocol: %d\n", protocol);

	if (protocol < 0 || protocol >= MHI_L3_NPROTO)
		return -EINVAL;

	mhi_protocols[protocol] = 1;

	return 0;
}
EXPORT_SYMBOL(mhi_register_protocol);

int
mhi_unregister_protocol(int protocol)
{
	DPRINTK("mhi_unregister_protocol: %d\n", protocol);

	if (protocol < 0 || protocol >= MHI_L3_NPROTO)
		return -EINVAL;

	mhi_protocols[protocol] = 0;

	return 0;
}
EXPORT_SYMBOL(mhi_unregister_protocol);


int
mhi_skb_send(
	struct sk_buff		*skb,
	struct net_device	*dev,
	u8			 proto)
{
	int err = 0;

	DPRINTK("mhi_skb_send: proto:%d skb_len:%d\n", proto, skb->len);

	skb->protocol = htons(ETH_P_MHI);
	skb->dev = dev;

	if (skb->pkt_type == PACKET_LOOPBACK) {
		skb_orphan(skb);
		netif_rx_ni(skb);
	} else {

		if ((proto == MHI_L3_XFILE) ||
			(proto == MHI_L3_LOW_PRIO_TEST)) {
			skb->priority = 1; /* Low prio */
		} else if ((proto == MHI_L3_AUDIO) ||
				(proto == MHI_L3_TEST_PRIO) ||
				(proto == MHI_L3_HIGH_PRIO_TEST)) {
			skb->priority = 6;	/* high prio */
		} else {
			skb->priority = 0;	/* medium prio */
		}
		err = dev_queue_xmit(skb);
	}

	return err;
}

int
mhi_skb_recv(
	struct sk_buff		*skb,
	struct net_device	*dev,
	struct packet_type	*type,
	struct net_device	*orig_dev)
{
	struct l2muxhdr		*l2hdr;

	u8     l3pid;
	u32    l3len;
	int    err;

	l2hdr = l2mux_hdr(skb);

	l3pid = l2mux_get_proto(l2hdr);
	l3len = l2mux_get_length(l2hdr);

	DPRINTK("mhi_skb_recv: skb_len:%d l3pid:%d l3len:%d\n",
				skb->len, l3pid, l3len);

	err = mhi_sock_rcv_multicast(skb, l3pid, l3len);

	return err;
}


static struct packet_type mhi_packet_type __read_mostly = {
	.type = cpu_to_be16(ETH_P_MHI),
	.func = mhi_skb_recv,
};


static int __init mhi_proto_init(void)
{
	int err;

	DPRINTK("mhi_proto_init\n");

	err = mhi_sock_init();
	if (err) {
		printk(KERN_ALERT "MHI socket layer registration failed\n");
		goto err0;
	}

	err = mhi_dgram_proto_init();
	if (err) {
		printk(KERN_ALERT "MHI DGRAM protocol layer reg failed\n");
		goto err1;
	}

	err = mhi_raw_proto_init();
	if (err) {
		printk(KERN_ALERT "MHI RAW protocol layer reg failed\n");
		goto err2;
	}

	dev_add_pack(&mhi_packet_type);

	return 0;

err2:
	mhi_dgram_proto_exit();
err1:
	mhi_sock_exit();
err0:
	return err;
}

static void __exit mhi_proto_exit(void)
{
	DPRINTK("mhi_proto_exit\n");

	dev_remove_pack(&mhi_packet_type);

	mhi_dgram_proto_exit();
	mhi_raw_proto_exit();
	mhi_sock_exit();
}

module_init(mhi_proto_init);
module_exit(mhi_proto_exit);

MODULE_ALIAS_NETPROTO(PF_MHI);

MODULE_AUTHOR("Petri Mattila <petri.to.mattila@renesasmobile.com>");
MODULE_DESCRIPTION("MHI Protocol Family for Linux");
MODULE_LICENSE("GPL");