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| author | David S. Miller <davem@davemloft.net> | 2013-12-05 19:45:14 -0500 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-12-05 19:45:14 -0500 |
| commit | 426e1fa31e0d8e982891e801c80b84b74f209f10 (patch) | |
| tree | bc53409418ffa918fb3f175639bc5c9245c4219f /Documentation/networking/timestamping.txt | |
| parent | e1ca87bb1b64b044163e686ff3bb71405156c561 (diff) | |
| parent | a4bcc795e9cc84902b86edbfbb755ecb38d11f91 (diff) | |
Merge branch 'siocghwtstamp' of git://git.kernel.org/pub/scm/linux/kernel/git/bwh/sfc-next
Ben Hutchings says:
====================
SIOCGHWTSTAMP ioctl
1. Add the SIOCGHWTSTAMP ioctl and update the timestamping
documentation.
2. Implement SIOCGHWTSTAMP in most drivers that support SIOCSHWTSTAMP.
3. Add a test program to exercise SIOC{G,S}HWTSTAMP.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'Documentation/networking/timestamping.txt')
| -rw-r--r-- | Documentation/networking/timestamping.txt | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt index 98097d8cb910..661d3c316a17 100644 --- a/Documentation/networking/timestamping.txt +++ b/Documentation/networking/timestamping.txt @@ -85,7 +85,7 @@ Filled in if SOF_TIMESTAMPING_SYS_HARDWARE is set. Requires support by the network device and will be empty without that support. -SIOCSHWTSTAMP: +SIOCSHWTSTAMP, SIOCGHWTSTAMP: Hardware time stamping must also be initialized for each device driver that is expected to do hardware time stamping. The parameter is defined in @@ -115,6 +115,10 @@ Only a processes with admin rights may change the configuration. User space is responsible to ensure that multiple processes don't interfere with each other and that the settings are reset. +Any process can read the actual configuration by passing this +structure to ioctl(SIOCGHWTSTAMP) in the same way. However, this has +not been implemented in all drivers. + /* possible values for hwtstamp_config->tx_type */ enum { /* @@ -157,7 +161,8 @@ DEVICE IMPLEMENTATION A driver which supports hardware time stamping must support the SIOCSHWTSTAMP ioctl and update the supplied struct hwtstamp_config with -the actual values as described in the section on SIOCSHWTSTAMP. +the actual values as described in the section on SIOCSHWTSTAMP. It +should also support SIOCGHWTSTAMP. Time stamps for received packets must be stored in the skb. To get a pointer to the shared time stamp structure of the skb call skb_hwtstamps(). Then |