Commit Graph

57 Commits

Author SHA1 Message Date
Peter Foley df68a01014 Documentation: use subdir-y to avoid unnecessary built-in.o files
Change the Documentation makefiles from obj-m to subdir-y
to avoid generating unnecessary built-in.o files since nothing
in Documentation/ is ever linked in to vmlinux.

Signed-off-by: Peter Foley <pefoley2@pefoley.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-09-26 11:02:55 +02:00
Sangjung Woo 5be876cf7e Documentation: fix two typos in watchdog-api.txt
This patch changes 'go of' to 'go off' and 'pretimout' to
'pretimeout'.

Signed-off-by: Sangjung Woo <sangjung.woo@samsung.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-08-05 22:43:21 +02:00
Marc van der Wal 0bcd0b6a47 watchdog: it87_wdt: Work around non-working CIR interrupts
On some hardware platforms, the it87_wdt watchdog resets the machine
despite the watchdog daemon running and writing to /dev/watchdog.

This is due to Consumer IR buffer underrun interrupts being used as
triggers to reset the timer.  On some buggy hardware implementations
such as the iEi AFL-12A-N270 single-board computer, this method does
not work.

However, resetting the timer by writing its original timeout value in
its configuration register over and over again suppresses the unwanted
reboots.

Add a module option (nocir), 0 by default in order not to break existing
setups.  Setting it to 1 enables the workaround.

Fixes bug #42801 <https://bugzilla.kernel.org/show_bug.cgi?id=42801>.
Tested primarily on Linux 3.5.7, applies cleanly on Linux 3.13.5.

Signed-off-by: Marc van der Wal <x0r+kernel@x0r.fr>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:33:55 +02:00
Andrew Chew c33a15974c watchdog: Add tegra watchdog
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: Andrew Chew <achew@nvidia.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-03-31 13:30:29 +02:00
Viresh Kumar 6e63a3a294 watchdog: delete mpcore_wdt driver
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/245998

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2013-07-11 21:47:58 +02:00
Fabio Porcedda 3048253ed9 watchdog: core: dt: add support for the timeout-sec dt property
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: Fabio Porcedda <fabio.porcedda@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2013-03-01 12:48:36 +01:00
Randy Dunlap 4b1c2f41c2 watchdog: fix watchdog-test.c build warning
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: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-08-29 17:12:58 +02:00
Ashish Jangam 664a0d7862 Watchdog: DA9052/53 PMIC watchdog support
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: Anthony Olech <Anthony.Olech@diasemi.com>
Signed-off-by: Ashish Jangam <ashish.jangam@kpitcummins.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30 07:56:12 +02:00
Hans de Goede e907df3272 watchdog: Add support for dynamically allocated watchdog_device structs
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: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30 07:55:31 +02:00
Hans de Goede f4e9c82f64 watchdog: Add Locking support
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: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30 07:55:23 +02:00
Alan Cox d6b469d915 watchdog: create all the proper device files
Create the watchdog class and it's associated devices.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30 07:54:46 +02:00
Alan Cox 45f5fed30a watchdog: Add multiple device support
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: Alan Cox <alan@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30 07:54:25 +02:00
Devendra Naga cad19fa664 Documentation/watchdog: Fix the file descriptor leak when no cmdline arg given
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: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-23 16:27:48 +02:00
Devendra Naga 3c2a6186c1 Documentation/watchdog: close the fd when cmdline arg given
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: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-23 16:27:40 +02:00
Devendra Naga 2deca73655 Documentation/watchdog: Fix a small typo
Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-23 16:27:00 +02:00
Viresh Kumar fd7b673c92 watchdog: Add support for WDIOC_GETTIMELEFT IOCTL in watchdog core
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: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-03-27 20:15:37 +02:00
Hans de Goede b10f7c12e0 watchdog: watchdog_dev: Let the driver update the timeout field on set_timeout success
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: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-03-27 20:07:43 +02:00
Wolfram Sang 5ba927e8ca watchdog: documentation: remove index-file
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: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-03-27 19:57:26 +02:00
Masanari Iida e19865219d Documentation: Fix typo in watchdog-kernel-api.txt
Correct spelling "retruns" to "returns" in
Documentations/watchdog/watchdog-kernel-api.txt

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-02-21 11:40:34 +01:00
Wolfram Sang 02861cca4b watchdog: documentation: describe nowayout in coversion-guide
nowayout is also handled by the watchdog core. Describe how this needs
to be addressed in the conversion guide.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-01-06 15:26:14 +01:00
Wim Van Sebroeck 9d36bc8cd8 watchdog: documentation: update index file
Add the convert_drivers_to_kernel_api.txt to the 00-INDEX file.

Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-01-06 15:25:47 +01:00
Wim Van Sebroeck ff0b3cd4a4 watchdog: add nowayout helpers to Watchdog Timer Driver Kernel API
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: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-01-06 15:22:04 +01:00
Wolfram Sang 74cd4c6739 Documentation: watchdog: add guide how to convert drivers to new framework
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2011-11-05 21:25:16 +01:00
Wim Van Sebroeck 3f43f68e29 watchdog: WatchDog Timer Driver Core - Add minimum and max timeout
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: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
2011-07-28 08:01:18 +00:00
Wim Van Sebroeck 78d88fc012 watchdog: WatchDog Timer Driver Core - Add ioctl call
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: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
2011-07-28 08:01:16 +00:00