Add a driver for the hardware watchdogs in NVIDIA Tegra SoCs (Tegra30 and
later).  This driver will configure one watchdog timer that will reset the
system in the case of a watchdog timeout.

This driver binds to the nvidia,tegra30-timer device node and gets its
register base from there.
Signed-off-by: NAndrew Chew <achew@nvidia.com>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Tested-by: NStephen Warren <swarren@nvidia.com>
Reviewed-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Interrupt request doesn't use the right API: The TWD watchdog uses a per-cpu
interrupt (usually interrupt #30), and the GIC configuration should flag it as
such. With this setup, request_irq() should fail, and the right API is
request_percpu_irq(), together with enable_percpu_irq()/disable_percpu_irq().

Nothing ensures the userspace ioctl() will end-up kicking the watchdog on the
right CPU.

There are no users of this driver since a long time and it makes more sense to
get rid of it as nobody is looking to fix it.

In case somebody wakes up after this has been removed and needs it, please
revert this driver and pick these updates (These were never pushed to mainline):

http://comments.gmane.org/gmane.linux.ports.arm.kernel/245998Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Add support for watchdog drivers to initialize/set the timeout field
of the watchdog_device structure. The timeout field is initialised
either with the module timeout parameter value (if valid) or with the
timeout-sec dt property (if valid). If both are invalid the initial
value is unchanged.
Signed-off-by: NFabio Porcedda <fabio.porcedda@gmail.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Fix compiler warning by making the function static:

Documentation/watchdog/src/watchdog-test.c:34:6: warning: no previous prototype for 'term'
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

This driver adds support for the watchdog functionality provided by
the Dialog Semiconductor DA9052 PMIC chip.

Tested on samsung smdkv6410 and i.mx53 QS boards.
Signed-off-by: NAnthony Olech <Anthony.Olech@diasemi.com>
Signed-off-by: NAshish Jangam <ashish.jangam@kpitcummins.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

If a driver's watchdog_device struct is part of a dynamically allocated
struct (which it often will be), merely locking the module is not enough,
even with a drivers module locked, the driver can be unbound from the device,
examples:
1) The root user can unbind it through sysfd
2) The i2c bus master driver being unloaded for an i2c watchdog

I will gladly admit that these are corner cases, but we still need to handle
them correctly.

The fix for this consists of 2 parts:
1) Add ref / unref operations, so that the driver can refcount the struct
   holding the watchdog_device struct and delay freeing it until any
   open filehandles referring to it are closed
2) Most driver operations will do IO on the device and the driver should not
   do any IO on the device after it has been unbound. Rather then letting each
   driver deal with this internally, it is better to ensure at the watchdog
   core level that no operations (other then unref) will get called after
   the driver has called watchdog_unregister_device(). This actually is the
   bulk of this patch.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

This patch fixes some potential multithreading issues, despite only
allowing one process to open the /dev/watchdog device, we can still get
called multiple times at the same time, since a program could be using thread,
or could share the fd after a fork.

This causes 2 potential problems:
1) watchdog_start / open do an unlocked test_n_set / test_n_clear,
   if these 2 race, the watchdog could be stopped while the active
   bit indicates it is running or visa versa.

2) Most watchdog_dev drivers probably assume that only one
   watchdog-op will get called at a time, this is not necessary
   true atm.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Create the watchdog class and it's associated devices.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

We keep the old /dev/watchdog interface file for the first watchdog via
miscdev. This is basically a cut and paste of the relevant interface code
from the rtc driver layer tweaked for watchdog.

Revised to fix problems noted by Hans de Goede
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

we start a infinite loop when user gives ./watchdog-test, and when user
ctrl + c's the program, we just exit immeadiately with out closing the
filedescriptor of the watchdog device. a signal handler is used to
do the job of closing the filedescriptor and exiting the program.
Signed-off-by: NDevendra Naga <devendra.aaru@gmail.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

in the watchdog test code, the ioctl is performed on the watchdog device
and just doing exit(0) so we leak a filedescripor.
Signed-off-by: NDevendra Naga <devendra.aaru@gmail.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Signed-off-by: NDevendra Naga <devendra.aaru@gmail.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

This patch adds support for WDIOC_GETTIMELEFT IOCTL in watchdog core. So, there
is another function pointer added to struct watchdog_ops, which can be passed by
drivers to support this IOCTL.

Related documentation is updated too.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

When a set_timeout operation succeeds this does not necessarily mean that
the exact timeout requested has been achieved, because the watchdog does not
necessarily have a 1 second resolution. So rather then have the core set
the timeout member of the watchdog_device struct to the exact requested
value, instead the driver should set it to the actually achieved timeout value.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

The 00-index file in the watchdog directory is, like many others,
outdated (conversion-howto is missing) and doesn't contain worthwhile
additional information. As it seems to be a maintenance burden without
much gain, simply remove it.
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Correct spelling "retruns" to "returns" in
Documentations/watchdog/watchdog-kernel-api.txt
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

nowayout is also handled by the watchdog core. Describe how this needs
to be addressed in the conversion guide.
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Add the convert_drivers_to_kernel_api.txt to the 00-INDEX file.
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Add two nowayout helpers for the Watchdog Timer Driver Kernel API.
And apply this to the already converted drivers.
Note: s3c2410_wdt lost the nowayout feature during the conversion.
Reviewed-by: NWolfram Sang <w.sang@pengutronix.de>
Acked-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Add min_timeout (minimum timeout) and max_timeout
values so that the framework can check if the new
timeout value is between the minimum and maximum
timeout values. If both values are 0, then the
framework will leave the check for the watchdog
device driver itself.
Signed-off-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>

Add support for extra ioctl calls by adding a
ioctl watchdog operation. This operation will be
called before we do our own handling of ioctl
commands. This way we can override the internal
ioctl command handling and we can also add
extra ioctl commands. The ioctl watchdog operation
should return the appropriate error codes or
-ENOIOCTLCMD if the ioctl command should be handled
through the internal ioctl handling of the framework.
Signed-off-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>

Add support for the nowayout feature to the
WatchDog Timer Driver Core framework.
This feature prevents the watchdog timer from being
stopped.
Signed-off-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>

Add support for the Magic Close feature to the
WatchDog Timer Driver Core framework.
Signed-off-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>

This part add's the WDIOC_SETTIMEOUT and WDIOC_GETTIMEOUT ioctl
functionality to the WatchDog Timer Driver Core framework.
Signed-off-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>

This part add's the WDIOC_SETOPTIONS ioctl functionality
to the WatchDog Timer Driver Core framework.
Signed-off-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>

This part add's the WDIOC_KEEPALIVE ioctl functionality to the
WatchDog Timer Driver Core framework. Please note that the
WDIOF_KEEPALIVEPING bit has to be set in the watchdog_info
options field.
Signed-off-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>

This part add's the basic ioctl functionality to the
WatchDog Timer Driver Core framework. The supported
ioctl call's are:
	WDIOC_GETSUPPORT
	WDIOC_GETSTATUS
	WDIOC_GETBOOTSTATUS
Signed-off-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>

The WatchDog Timer Driver Core is a framework
that contains the common code for all watchdog-driver's.
It also introduces a watchdog device structure and the
operations that go with it.

This is the introduction of this framework. This part
supports the minimal watchdog userspace API (or with
other words: the functionality to use /dev/watchdog's
open, release and write functionality as defined in
the simplest watchdog API). Extra functionality will
follow in the next set of patches.
Signed-off-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Add an entry for imx2_wdt in watchdog-parameters.txt
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Move the limited watchdog driver help from kernel-parameters.txt
to Documentation/watchdog/watchdog-parameters.txt and add info to it
for all watchdog drivers except the ones that have driver-specific
files already.

Correct minor comments and MODULE_PARM_DESC() text in 2 places.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

In the watchdog-test program and watchdog-api.txt, pass the values to
the WDIOC_SETOPTIONS ioctl as a pointer to an integer containing the
values intead of directly in the third ioctl argument. The actual
watchdog drivers in drivers/watchdog don't read the options directly
from the argument but use get_user and copy_from_user.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

Don't terminate the watchdog daemon when fsync() fails because no
watchdog driver actually implements the fsync() syscall.
Signed-off-by: NGiel van Schijndel <me@mortis.eu>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Fix up -Wmissing-prototypes in compileable userspace code, mainly under
Documentation/.
Signed-off-by: NLadinu Chandrasinghe <ladinu.pub@gmail.com>
Signed-off-by: NTrevor Keith <tsrk@tsrk.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a priority option so that the user can choose if we do the NMI
first or last.
Signed-off-by: NThomas Mingarelli <thomas.mingarelli@hp.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Add NMI sourcing functionality (Can only be active if nmi_watchdog is
inactive).
Signed-off-by: NThomas Mingarelli <thomas.mingarelli@hp.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently source files in the Documentation/ sub-dir can easily bit-rot
since they are not generally buildable, either because they are hidden in
text files or because there are no Makefile rules for them.  This needs to
be fixed so that the source files remain usable and good examples of code
instead of bad examples.

Add the ability to build source files that are in the Documentation/ dir.
Add to Kconfig as "BUILD_DOCSRC" config symbol.

Use "CONFIG_BUILD_DOCSRC=1 make ..." to build objects from the
Documentation/ sources.  Or enable BUILD_DOCSRC in the *config system.
However, this symbol depends on HEADERS_CHECK since the header files need
to be installed (for userspace builds).

Built (using cross-tools) for x86-64, i386, alpha, ia64, sparc32,
sparc64, powerpc, sh, m68k, & mips.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Reviewed-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It was not clear what the difference is/was between the 
nowayout feature and the Magic Close feature.
Signed-off-by: N"Andrew Dyer" <amdyer@gmail.com>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>