xref: /linux/net/core/timestamping.c (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
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 
26 static 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 
35 void 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 }
56 EXPORT_SYMBOL_GPL(skb_clone_tx_timestamp);
57 
58 bool skb_defer_rx_timestamp(struct sk_buff *skb)
59 {
60 	struct phy_device *phydev;
61 	unsigned int type;
62 
63 	if (skb_headroom(skb) < ETH_HLEN)
64 		return false;
65 	__skb_push(skb, ETH_HLEN);
66 
67 	type = classify(skb);
68 
69 	__skb_pull(skb, ETH_HLEN);
70 
71 	if (type == PTP_CLASS_NONE)
72 		return false;
73 
74 	phydev = skb->dev->phydev;
75 	if (likely(phydev->drv->rxtstamp))
76 		return phydev->drv->rxtstamp(phydev, skb, type);
77 
78 	return false;
79 }
80 EXPORT_SYMBOL_GPL(skb_defer_rx_timestamp);
81