1/*
2 * PTP 1588 clock support - support for timestamping in PHY devices
3 *
4 * Copyright (C) 2010 OMICRON electronics GmbH
5 *
6 *  This program is free software; you can redistribute it and/or modify
7 *  it under the terms of the GNU General Public License as published by
8 *  the Free Software Foundation; either version 2 of the License, or
9 *  (at your option) any later version.
10 *
11 *  This program is distributed in the hope that it will be useful,
12 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 *  GNU General Public License for more details.
15 *
16 *  You should have received a copy of the GNU General Public License
17 *  along with this program; if not, write to the Free Software
18 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20#include <linux/errqueue.h>
21#include <linux/phy.h>
22#include <linux/ptp_classify.h>
23#include <linux/skbuff.h>
24#include <linux/export.h>
25
26static unsigned int classify(const struct sk_buff *skb)
27{
28	if (likely(skb->dev && skb->dev->phydev &&
29		   skb->dev->phydev->drv))
30		return ptp_classify_raw(skb);
31	else
32		return PTP_CLASS_NONE;
33}
34
35void skb_clone_tx_timestamp(struct sk_buff *skb)
36{
37	struct phy_device *phydev;
38	struct sk_buff *clone;
39	unsigned int type;
40
41	if (!skb->sk)
42		return;
43
44	type = classify(skb);
45	if (type == PTP_CLASS_NONE)
46		return;
47
48	phydev = skb->dev->phydev;
49	if (likely(phydev->drv->txtstamp)) {
50		clone = skb_clone_sk(skb);
51		if (!clone)
52			return;
53		phydev->drv->txtstamp(phydev, clone, type);
54	}
55}
56EXPORT_SYMBOL_GPL(skb_clone_tx_timestamp);
57
58bool skb_defer_rx_timestamp(struct sk_buff *skb)
59{
60	struct phy_device *phydev;
61	unsigned int type;
62
63	if (!skb->dev || !skb->dev->phydev || !skb->dev->phydev->drv)
64		return false;
65
66	if (skb_headroom(skb) < ETH_HLEN)
67		return false;
68
69	__skb_push(skb, ETH_HLEN);
70
71	type = ptp_classify_raw(skb);
72
73	__skb_pull(skb, ETH_HLEN);
74
75	if (type == PTP_CLASS_NONE)
76		return false;
77
78	phydev = skb->dev->phydev;
79	if (likely(phydev->drv->rxtstamp))
80		return phydev->drv->rxtstamp(phydev, skb, type);
81
82	return false;
83}
84EXPORT_SYMBOL_GPL(skb_defer_rx_timestamp);
85