From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Oeser <netdev@axxeo.de>
Subject: Re: [RFC][PATCH 1/1] net: support for hardware timestamping
Date: Wed, 30 Jul 2008 11:34:49 +0200
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Cc: Octavian Purdila <opurdila@ixiacom.com>,
	Stephen Hemminger <shemminger@vyatta.com>,
	netdev@vger.kernel.org
To: Patrick Ohly <patrick.ohly@intel.com>
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Hi Patrick,

Patrick Ohly schrieb:
> Perhaps the parameter of the new
> SO_TXTIMESTAMP can be a multi-value? 0 = no TX time stamps, 1 = TX time
> stamp in hardware if possible with software as fallback, 2 = only
> hardware TX time stamps. Either that, or use the same new socket flag as
> for RX time stamps.

Perhaps we can make it a bitmask (please choose a good prefix instead of XXX):

enum {
	XXX_SOFTWARE_TX_TIMESTAMP = (1 << 0),
	XXX_SOFTWARE_RX_TIMESTAMP = (1 << 1),
	XXX_DRIVER_TX_TIMESTAMP	  = (1 << 2),
	XXX_DRIVER_RX_TIMESTAMP	  = (1 << 3),
};

That way we can express everything required so far and have some bits left 
to define precision, system time correlation and more.


Best Regards

Ingo Oeser