[patch] usbnet: add timestamping support

In order to make USB-to-Ethernet-adapters (depending on usbnet) support
time stamping, the "skb_defer_rx_timestamp" and "skb_tx_timestamp"
function calls are added.

I considered to put these calls between #ifdef's to make them dependent
on CONFIG_NETWORK_PHY_TIMESTAMPING. I decided not to do so because except
the check whether the current packet is a PTP packet (and this check
should be fast) no overhead occurs. But let me know your opinion about
that one.

Looking forward to your comments,
Michael

Signed-off-by: Michael Riesch <redacted>
---
 drivers/net/usb/usbnet.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index ce395fe..cdb9588 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c

@@ -238,6 +238,10 @@ void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
         netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
                   skb->len + sizeof (struct ethhdr), skb->protocol);
         memset (skb->cb, 0, sizeof (struct skb_data));
+
+        if (skb_defer_rx_timestamp(skb))
+                return;
+
         status = netif_rx (skb);
         if (status != NET_RX_SUCCESS)
                 netif_dbg(dev, rx_err, dev->net,

@@ -1053,6 +1057,8 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
         unsigned long                flags;
         int retval;

+        skb_tx_timestamp(skb);
+
         // some devices want funky USB-level framing, for
         // win32 driver (usually) and/or hardware quirks
         if (info->tx_fixup) {

-- 
1.7.0.4

Quoting Michael Riesch [off-list ref]:

I considered to put these calls between #ifdef's to make them dependent
on CONFIG_NETWORK_PHY_TIMESTAMPING. I decided not to do so because except
the check whether the current packet is a PTP packet (and this check
should be fast) no overhead occurs. But let me know your opinion about
that one.

Come to think of it the #ifdef's are definitely unnecessary because these
functions are no-ops with CONFIG_NETWORK_PHY_TIMESTAMPING not set.

Regards,
Michael

From: Michael Riesch <redacted>
Date: Wed, 21 Sep 2011 12:11:51 +0200

Patch is severly corrupted by your email client.

Correct this (see Documentation/email-clients.txt), send a test patch
to yourself, and only resubmit this change when you can successfully
apply a patch you send to youself.

On Wed, 2011-09-28 at 03:20 -0400, David Miller wrote:

Patch is severly corrupted by your email client.

Correct this (see Documentation/email-clients.txt), send a test patch
to yourself, and only resubmit this change when you can successfully
apply a patch you send to youself.

Sorry about that. I switched to git-send-email and tested it. I hope it
works now.

Regards, Michael