Merge tag 'docs-4.5' of git://git.lwn.net/linux

Pull documentation updates from Jon Corbet:
 "A relatively boring cycle in the docs tree.  There's a few kernel-doc
  fixes and various document tweaks.

  One patch reaches out of the documentation subtree to fix a comment in
  init/do_mounts_rd.c.  There didn't seem to be anybody more appropriate
  to take that one, so I accepted it"

* tag 'docs-4.5' of git://git.lwn.net/linux: (29 commits)
  thermal: add description for integral_cutoff unit
  Documentation: update libhugetlbfs site url
  Documentation: Explain pci=conf1,conf2 more verbosely
  DMA-API: fix confusing sentence in Documentation/DMA-API.txt
  Documentation: translations: update linux cross reference link
  Documentation: fix typo in CodingStyle
  init, Documentation: Remove ramdisk_blocksize mentions
  Documentation-getdelays: Apply a recommendation from "checkpatch.pl" in main()
  Documentation: HOWTO: update versions from 3.x to 4.x
  Documentation: remove outdated references from translations
  Doc: treewide: Fix grammar "a" to "an"
  Documentation: cpu-hotplug: Fix sysfs mount instructions
  can-doc: Add hint about getting timestamps
  Fix CFQ I/O scheduler parameter name in documentation
  Documentation: arm: remove dead links from Marvell Berlin docs
  Documentation: HOWTO: update code cross reference link
  Doc: Docbook/iio: Fix typo in iio.tmpl
  DocBook: make index.html generation less verbose by default
  DocBook: Cleanup: remove an unused $(call) line
  DocBook: Add a help message for DOCBOOKS env var
  ...

1 files changed, 9 insertions, 0 deletions

diff --git a/Documentation/networking/can.txt b/Documentation/networking/can.txt
index 05fd83b..6ab619f 100644
--- a/Documentation/networking/can.txt
+++ b/Documentation/networking/can.txt
@@ -372,6 +372,15 @@ solution for a couple of reasons:
     nbytes = sendto(s, &frame, sizeof(struct can_frame),
                     0, (struct sockaddr*)&addr, sizeof(addr));
 
+  An accurate timestamp can be obtained with an ioctl(2) call after reading
+  a message from the socket:
+
+    struct timeval tv;
+    ioctl(s, SIOCGSTAMP, &tv);
+
+  The timestamp has a resolution of one microsecond and is set automatically
+  at the reception of a CAN frame.
+
   Remark about CAN FD (flexible data rate) support:
 
   Generally the handling of CAN FD is very similar to the formerly described