Merge tag 'docs-4.15' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A relatively calm cycle for the docs tree again.

  - The old driver statement has been added to the kernel docs.

  - We have a couple of new helper scripts. find-unused-docs.sh from
    Sayli Karnic will point out kerneldoc comments that are not actually
    used in the documentation. Jani Nikula's
    documentation-file-ref-check finds references to non-existing files.

  - A new ftrace document from Steve Rostedt.

  - Vinod Koul converted the dmaengine docs to RST

  Beyond that, it's mostly simple fixes.

  This set reaches outside of Documentation/ a bit more than most. In
  all cases, the changes are to comment docs, mostly from Randy, in
  places where there didn't seem to be anybody better to take them"

* tag 'docs-4.15' of git://git.lwn.net/linux: (52 commits)
  documentation: fb: update list of available compiled-in fonts
  MAINTAINERS: update DMAengine documentation location
  dmaengine: doc: ReSTize pxa_dma doc
  dmaengine: doc: ReSTize dmatest doc
  dmaengine: doc: ReSTize client API doc
  dmaengine: doc: ReSTize provider doc
  dmaengine: doc: Add ReST style dmaengine document
  ftrace/docs: Add documentation on how to use ftrace from within the kernel
  bug-hunting.rst: Fix an example and a typo in a Sphinx tag
  scripts: Add a script to find unused documentation
  samples: Convert timers to use timer_setup()
  documentation: kernel-api: add more info on bitmap functions
  Documentation: fix selftests related file refs
  Documentation: fix ref to power basic-pm-debugging
  Documentation: fix ref to trace stm content
  Documentation: fix ref to coccinelle content
  Documentation: fix ref to workqueue content
  Documentation: fix ref to sphinx/kerneldoc.py
  Documentation: fix locking rt-mutex doc refs
  docs: dev-tools: correct Coccinelle version number
  ...

1 files changed, 14 insertions, 0 deletions

diff --git a/include/asm-generic/div64.h b/include/asm-generic/div64.h
index d2013064dc69..dc9726fdac8f 100644
--- a/include/asm-generic/div64.h
+++ b/include/asm-generic/div64.h
@@ -26,6 +26,20 @@
 
 #if BITS_PER_LONG == 64
 
+/**
+ * do_div - returns 2 values: calculate remainder and update new dividend
+ * @n: pointer to uint64_t dividend (will be updated)
+ * @base: uint32_t divisor
+ *
+ * Summary:
+ * ``uint32_t remainder = *n % base;``
+ * ``*n = *n / base;``
+ *
+ * Return: (uint32_t)remainder
+ *
+ * NOTE: macro parameter @n is evaluated multiple times,
+ * beware of side effects!
+ */
 # define do_div(n,base) ({					\
 	uint32_t __base = (base);				\
 	uint32_t __rem;						\