Merge tag 'docs-5.3' of git://git.lwn.net/linux

Pull Documentation updates from Jonathan Corbet:
 "It's been a relatively busy cycle for docs:

   - A fair pile of RST conversions, many from Mauro. These create more
     than the usual number of simple but annoying merge conflicts with
     other trees, unfortunately. He has a lot more of these waiting on
     the wings that, I think, will go to you directly later on.

   - A new document on how to use merges and rebases in kernel repos,
     and one on Spectre vulnerabilities.

   - Various improvements to the build system, including automatic
     markup of function() references because some people, for reasons I
     will never understand, were of the opinion that
     :c:func:``function()`` is unattractive and not fun to type.

   - We now recommend using sphinx 1.7, but still support back to 1.4.

   - Lots of smaller improvements, warning fixes, typo fixes, etc"

* tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits)
  docs: automarkup.py: ignore exceptions when seeking for xrefs
  docs: Move binderfs to admin-guide
  Disable Sphinx SmartyPants in HTML output
  doc: RCU callback locks need only _bh, not necessarily _irq
  docs: format kernel-parameters -- as code
  Doc : doc-guide : Fix a typo
  platform: x86: get rid of a non-existent document
  Add the RCU docs to the core-api manual
  Documentation: RCU: Add TOC tree hooks
  Documentation: RCU: Rename txt files to rst
  Documentation: RCU: Convert RCU UP systems to reST
  Documentation: RCU: Convert RCU linked list to reST
  Documentation: RCU: Convert RCU basic concepts to reST
  docs: filesystems: Remove uneeded .rst extension on toctables
  scripts/sphinx-pre-install: fix out-of-tree build
  docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/
  Documentation: PGP: update for newer HW devices
  Documentation: Add section about CPU vulnerabilities for Spectre
  Documentation: platform: Delete x86-laptop-drivers.txt
  docs: Note that :c:func: should no longer be used
  ...

1 files changed, 63 insertions, 0 deletions

diff --git a/Documentation/watchdog/wdt.rst b/Documentation/watchdog/wdt.rst
new file mode 100644
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+============================================================
+WDT Watchdog Timer Interfaces For The Linux Operating System
+============================================================
+
+Last Reviewed: 10/05/2007
+
+Alan Cox <alan@lxorguk.ukuu.org.uk>
+
+	- ICS	WDT501-P
+	- ICS	WDT501-P (no fan tachometer)
+	- ICS	WDT500-P
+
+All the interfaces provide /dev/watchdog, which when open must be written
+to within a timeout or the machine will reboot. Each write delays the reboot
+time another timeout. In the case of the software watchdog the ability to
+reboot will depend on the state of the machines and interrupts. The hardware
+boards physically pull the machine down off their own onboard timers and
+will reboot from almost anything.
+
+A second temperature monitoring interface is available on the WDT501P cards.
+This provides /dev/temperature. This is the machine internal temperature in
+degrees Fahrenheit. Each read returns a single byte giving the temperature.
+
+The third interface logs kernel messages on additional alert events.
+
+The ICS ISA-bus wdt card cannot be safely probed for. Instead you need to
+pass IO address and IRQ boot parameters.  E.g.::
+
+	wdt.io=0x240 wdt.irq=11
+
+Other "wdt" driver parameters are:
+
+	===========	======================================================
+	heartbeat	Watchdog heartbeat in seconds (default 60)
+	nowayout	Watchdog cannot be stopped once started (kernel
+			build parameter)
+	tachometer	WDT501-P Fan Tachometer support (0=disable, default=0)
+	type		WDT501-P Card type (500 or 501, default=500)
+	===========	======================================================
+
+Features
+--------
+
+================   =======	   =======
+		   WDT501P	   WDT500P
+================   =======	   =======
+Reboot Timer	   X               X
+External Reboot	   X	           X
+I/O Port Monitor   o		   o
+Temperature	   X		   o
+Fan Speed          X		   o
+Power Under	   X               o
+Power Over         X               o
+Overheat           X               o
+================   =======	   =======
+
+The external event interfaces on the WDT boards are not currently supported.
+Minor numbers are however allocated for it.
+
+
+Example Watchdog Driver:
+
+	see samples/watchdog/watchdog-simple.c