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2017-07-03watchdog: uniphier: add UniPhier watchdog driverKeiji Hayashibara
Add a watchdog driver for Socionext UniPhier series SoC. Note that the timeout value for this device must be a power of 2 because of the specification. Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2017-05-19iTCO_wdt: all versions count down twicePaolo Bonzini
The ICH9 is listed as having TCO v2, and indeed the behavior in the datasheet corresponds to v2 (for example the NO_REBOOT flag is accessible via the 16KiB-aligned Root Complex Base Address). However, the TCO counts twice just like in v1; the documentation of the SECOND_TO_STS bit says: "ICH9 sets this bit to 1 to indicate that the TIMEOUT bit had been (or is currently) set and a second timeout occurred before the TCO_RLD register was written. If this bit is set and the NO_REBOOT config bit is 0, then the ICH9 will reboot the system after the second timeout. The same can be found in the BayTrail (Atom E3800) datasheet, and even HOWTOs around the Internet say that it will reboot after _twice_ the specified heartbeat. I did not find the Apollo Lake datasheet, but because v4/v5 has a SECOND_TO_STS bit just like the previous version I'm enabling this for Apollo Lake as well. Cc: linux-watchdog@vger.kernel.org Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2017-02-24watchdog: Introduce watchdog_stop_on_unregister helperGuenter Roeck
Many watchdog drivers explicitly stop the watchdog when unregistering it. While it is unclear if this is actually needed (the whatdog should not be running at that time if it can be stopped), introduce a helper to explicitly stop the watchdog in the watchdog core when unregistering it. This helps reducing driver code size while retaining functionality. Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-02-24watchdog: nic7018_wdt: Add NIC7018 watchdog driverHui Chun Ong
Add support for the watchdog timer on PXI Embedded Controller. Signed-off-by: Hui Chun Ong <hui.chun.ong@ni.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-10-24docs: fix locations of several documents that got movedMauro Carvalho Chehab
The previous patch renamed several files that are cross-referenced along the Kernel documentation. Adjust the links to point to the right places. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-10-14Merge tag 'linux-kselftest-4.9-rc1-update' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kselftest updates from Shuah Khan: "This update consists of: - Fixes and improvements to existing tests - Moving code from Documentation to selftests, samples, and tools: * Moves dnotify_test, prctl, ptp, vDSO, ia64, watchdog, and networking tests from Documentation to selftests. * Moves mic/mpssd, misc-devices/mei, timers, watchdog, auxdisplay, and blackfin examples from Documentation to samples. * Moves accounting, laptops/dslm, and pcmcia/crc32hash tools from Documentation to tools. * Deletes BUILD_DOCSRC and its dependencies" * tag 'linux-kselftest-4.9-rc1-update' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (21 commits) selftests/futex: Check ANSI terminal color support Doc: update 00-INDEX files to reflect the runnable code move samples: move blackfin gptimers-example from Documentation tools: move pcmcia crc32hash tool from Documentation tools: move laptops dslm tool from Documentation tools: move accounting tool from Documentation samples: move auxdisplay example code from Documentation samples: move watchdog example code from Documentation samples: move timers example code from Documentation samples: move misc-devices/mei example code from Documentation samples: move mic/mpssd example code from Documentation selftests: Move networking/timestamping from Documentation selftests: move watchdog tests from Documentation/watchdog selftests: move ia64 tests from Documentation/ia64 selftests: move vDSO tests from Documentation/vDSO selftests: move ptp tests from Documentation/ptp selftests: move prctl tests from Documentation/prctl selftests: move dnotify_test from Documentation/filesystems selftests/timers: Add missing error code assignment before test selftests/zram: replace ZRAM_LZ4_COMPRESS ...
2016-10-08watchdog: add watchdog pretimeout governor frameworkVladimir Zapolskiy
The change adds a simple watchdog pretimeout framework infrastructure, its purpose is to allow users to select a desired handling of watchdog pretimeout events, which may be generated by some watchdog devices. A user selects a default watchdog pretimeout governor during compilation stage. Watchdogs with WDIOF_PRETIMEOUT capability now have one more device attribute in sysfs, pretimeout_governor attribute is intended to display the selected watchdog pretimeout governor. The framework has no impact at runtime on watchdog devices with no WDIOF_PRETIMEOUT capability set. Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-09-24watchdog: add pretimeout support to the coreWolfram Sang
Since the watchdog framework centrializes the IOCTL interfaces of device drivers now, SETPRETIMEOUT and GETPRETIMEOUT need to be added in the common code. Signed-off-by: Robin Gong <b38343@freescale.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> [vzapolskiy: added conditional pretimeout sysfs attribute visibility] Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-09-23samples: move watchdog example code from DocumentationShuah Khan
Move watchdog examples to samples and remove it from Documentation Makefile. Create a new Makefile to build watchdog. It can be built from top level directory or from watchdog directory: Run make -C samples/watchdog or cd samples/watchdog; make Acked-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2016-09-20selftests: move watchdog tests from Documentation/watchdogShuah Khan
Remove watchdog-test from Makefile to move the test to selftests. Add Makefile and .gitignore for watchdog-test. watchdog-test will not be run as part of selftests suite and will not be included in install targets. It can be built separately for now. Acked-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2016-07-25Documentation/watchdog: check return value for magic closeArnd Bergmann
A recent commit added a write to the watchdog test code for doing the "magic close", but that caused a compile-time warning: Documentation/watchdog/src/watchdog-test.c: In function ‘main’: Documentation/watchdog/src/watchdog-test.c:94:5: warning: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Wunused-result] This changes the code to print a runtime warning if the write fails. Fixes: 5a2d3de19602 ("Documentation/watchdog: add support for magic close to watchdog-test") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Timur Tabi <timur@codeaurora.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-07-19watchdog: Implement status function in watchdog coreGuenter Roeck
Up to now, the watchdog status function called a driver function, which was supposed to return the watchdog status. All but one driver using the watchdog core did not implement this function, and the driver implementing it did not implement it correctly (the function is supposed to return WDIOF_ flags). At the same time, at least some of the status information can be provided by the watchdog core. Provide the available status bits directly from the watchdog driver core. Call the driver status function if it exists to get the boot status, but always provide WDIOF_MAGICCLOSE and WDIOF_KEEPALIVEPING internally. This patch makes the 'status' sysfs attribute always available. This attribute is now displayed as hex number with 0x prepended to be easier to decode. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-07-17Documentation/watchdog: add support for magic close to watchdog-testTimur Tabi
Some drivers have the WDIOF_MAGICCLOSE set, which means that applications need to write 'V' to the watchdog device before closing, otherwise the driver won't stop the watchdog timer. Signed-off-by: Timur Tabi <timur@codeaurora.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-07-17Documentation/watchdog: use stdout instead of stderr in watchdog-testTimur Tabi
The watchdog-test utility outputs all messages to stderr, even those that are not error messages. Output to stdout instead. Instead of flushing the output after every write, just disabled the output buffer. Also display a dot for every ping of the watchdog, so that the user knows that it's working. Signed-off-by: Timur Tabi <timur@codeaurora.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-07-17watchdog: Improve description of min_hw_heartbeat_msGuenter Roeck
The description of min_hw_heartbeat_ms is misleading and needs some improvements. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-07-17watchdog: hpwdt: remove email address from docBrian Boylston
Remove Tom's email address from the documentation Signed-off-by: Brian Boylston <brian.boylston@hpe.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-05-14Documentation: Add ebc-c384_wdt watchdog-parameters.txt entryWilliam Breathitt Gray
The WinSystems EBC-C384 watchdog timer driver supports two module parameters: timeout and nowayout. These parameters should be documented in the watchdog-parameters.txt file. Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-05-14watchdog: hpwdt: Adjust documentation to match latest kernel module parameters.Nigel Croxon
Adjust documentation to match latest kernel module parameters. Signed-off-by: Nigel Croxon <nigel.croxon@hpe.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-03-19Merge git://www.linux-watchdog.org/linux-watchdogLinus Torvalds
Pull watchdog updates from Wim Van Sebroeck: - new drivers for: NI 903x/913x watchdog driver, WinSystems EBC-C384 watchdog timer and ARM SBSA watchdog driver - Support for NCT6102D devices - Improvements of the generic watchdog framework (improve restart handler, make set_timeout optional, introduce infrastructure triggered keepalives, ... - improvements on the pnx4008 watchdog driver - several smaller fixes and improvements * git://www.linux-watchdog.org/linux-watchdog: (28 commits) watchdog: Ensure that wdd is not dereferenced if NULL watchdog: imx2: Convert to use infrastructure triggered keepalives watchdog: dw_wdt: Convert to use watchdog infrastructure watchdog: Add support for minimum time between heartbeats watchdog: Make stop function optional watchdog: Introduce WDOG_HW_RUNNING flag watchdog: Introduce hardware maximum heartbeat in watchdog core watchdog: Make set_timeout function optional arm: lpc32xx: remove restart handler arm: lpc32xx: phy3250 remove restart hook watchdog: pnx4008: restart: support "cmd" from userspace watchdog: pnx4008: add support for soft reset watchdog: pnx4008: add restart handler watchdog: pnx4008: update logging during power-on watchdog: tangox_wdt: test clock rate to avoid division by 0 watchdog: atlas7_wdt: test clock rate to avoid division by 0 watchdog: s3c2410_wdt: Add max and min timeout values Watchdog: introduce ARM SBSA watchdog driver Documentation: add sbsa-gwdt driver documentation watchdog: Add watchdog timer support for the WinSystems EBC-C384 ...
2016-03-16watchdog: Add support for minimum time between heartbeatsGuenter Roeck
Some watchdogs require a minimum time between heartbeats. Examples are the watchdogs in DA9062 and AT91SAM9x. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-03-16watchdog: Make stop function optionalGuenter Roeck
Not all hardware watchdogs can be stopped. The driver for such watchdogs would typically only set the WATCHDOG_HW_RUNNING flag in its stop function. Make the stop function optional and set WATCHDOG_HW_RUNNING in the watchdog core if it is not provided. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-03-16watchdog: Introduce WDOG_HW_RUNNING flagGuenter Roeck
The WDOG_HW_RUNNING flag is expected to be set by watchdog drivers if the hardware watchdog is running. If the flag is set, the watchdog subsystem will ping the watchdog even if the watchdog device is closed. The watchdog driver stop function is now optional and may be omitted if the watchdog can not be stopped. If stopping the watchdog is not possible but the driver implements a stop function, it is responsible to set the WDOG_HW_RUNNING flag in its stop function. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-03-16watchdog: Introduce hardware maximum heartbeat in watchdog coreGuenter Roeck
Introduce an optional hardware maximum heartbeat in the watchdog core. The hardware maximum heartbeat can be lower than the maximum timeout. Drivers can set the maximum hardware heartbeat value in the watchdog data structure. If the configured timeout exceeds the maximum hardware heartbeat, the watchdog core enables a timer function to assist sending keepalive requests to the watchdog driver. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-03-16watchdog: Make set_timeout function optionalGuenter Roeck
For some watchdogs, the watchdog driver handles timeout changes without explicitly setting any registers. In this situation, the watchdog driver might only set the 'timeout' variable but do nothing else. This can as well be handled by the infrastructure, so make the set_timeout callback optional. If WDIOF_SETTIMEOUT is configured but the .set_timeout callback is not available, update the timeout variable in the infrastructure code. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-03-04Documentation: add sbsa-gwdt driver documentationFu Wei
The sbsa-gwdt.txt documentation in devicetree/bindings/watchdog is for introducing SBSA(Server Base System Architecture) Generic Watchdog device node info into FDT. Also add sbsa-gwdt introduction in watchdog-parameters.txt Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Fu Wei <fu.wei@linaro.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-03-01watchdog: ni903x_wdt: Add NI 903x/913x watchdog driverKyle Roeschley
Add support for the watchdog timer on NI cRIO-903x and cDAQ-913x real- time controllers. Signed-off-by: Jeff Westfahl <jeff.westfahl@ni.com> Signed-off-by: Kyle Roeschley <kyle.roeschley@ni.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-01-31Add sun4v_wdt watchdog driverwim.coekaerts@oracle.com
This driver adds sparc hypervisor watchdog support. The default timeout is 60 seconds and the range is between 1 and 31536000 seconds. Both watchdog-resolution and watchdog-max-timeout MD properties settings are supported. Signed-off-by: Wim Coekaerts <wim.coekaerts@oracle.com> Reviewed-by: Julian Calaby <julian.calaby@gmail.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-11watchdog: Drop pointer to watchdog device from struct watchdog_deviceGuenter Roeck
The lifetime of the watchdog device pointer is different from the lifetime of its character device. Remove it entirely to avoid race conditions. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-01-11watchdog: Add support for creating driver specific sysfs attributesGuenter Roeck
The Zodiac watchdog driver attaches additional sysfs attributes to the watchdog device. This has a number of problems: The watchdog device lifetime differs from the driver lifetime, and the device structure should therefore not be accessed from drivers. Also, creating sysfs attributes after driver registration results in a potential race condition if user space expects the attributes to exist but they don't exist yet. Add support for creating driver specific sysfs attributes to the watchdog core to solve the problems. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-12-29watchdog: Separate and maintain variables based on variable lifetimeGuenter Roeck
All variables required by the watchdog core to manage a watchdog are currently stored in struct watchdog_device. The lifetime of those variables is determined by the watchdog driver. However, the lifetime of variables used by the watchdog core differs from the lifetime of struct watchdog_device. To remedy this situation, watchdog drivers can implement ref and unref callbacks, to be used by the watchdog core to lock struct watchdog_device in memory. While this solves the immediate problem, it depends on watchdog drivers to actually implement the ref/unref callbacks. This is error prone, often not implemented in the first place, or not implemented correctly. To solve the problem without requiring driver support, split the variables in struct watchdog_device into two data structures - one for variables associated with the watchdog driver, one for variables associated with the watchdog core. With this approach, the watchdog core can keep track of its variable lifetime and no longer depends on ref/unref callbacks in the driver. As a side effect, some of the variables originally in struct watchdog_driver are now private to the watchdog core and no longer visible in watchdog drivers. As a side effect of the changes made, an ioctl will now always fail with -ENODEV after a watchdog device was unregistered with the character device still open. Previously, it would only fail with -ENODEV in some situations. Also, ioctl operations are now atomic from driver perspective. With this change, it is now guaranteed that the driver will not unregister a watchdog between a timeout change and the subsequent ping. The 'ref' and 'unref' callbacks in struct watchdog_driver are no longer used and marked as deprecated. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-12-13watchdog: core: add reboot notifier supportDamien Riegel
Many watchdog drivers register a reboot notifier in order to stop the watchdog on system reboot. Thus we can factorize this code in the watchdog core. For that purpose, a new notifier block is added in watchdog_device for internal use only, as well as a new watchdog_stop_on_reboot helper function. If this helper is called, watchdog core registers the related notifier block and will stop the watchdog when SYS_HALT or SYS_DOWN is received. Since this operation can be critical on some platforms, abort the device registration if the reboot notifier registration fails. Suggested-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com> Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-12-13watchdog: core: add restart handler supportDamien Riegel
Many watchdog drivers implement the same code to register a restart handler. This patch provides a generic way to set such a function. The patch adds a new restart watchdog operation. If a restart priority greater than 0 is needed, the driver can call watchdog_set_restart_priority to set it. Suggested-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-09-09Documentation/watchdog: add timeout and ping rate control to watchdog-test.cTimur Tabi
The watchdog test program is much more useful if it can configure the timeout value and ping rate. This will allow you to test actual timeouts. Adds the -t parameter to set the timeout value (in seconds), and -p to set the ping rate (number of seconds between pings). Signed-off-by: Timur Tabi <timur@codeaurora.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-07-01watchdog: omap_wdt: early_enable module parameterLars Poeschel
Add a early_enable module parameter to the omap_wdt that starts the watchdog on module insertion. The default value is 0 which does not start the watchdog - which also does not change the behavior if the parameter is not given. Signed-off-by: Lars Poeschel <poeschel@lemonage.de> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-06-29watchdog: watchdog_core: Add watchdog registration deferral mechanismJean-Baptiste Theou
Currently, watchdog subsystem require the misc subsystem to register a watchdog. This may not be the case in case of an early registration of a watchdog, which can be required when the watchdog cannot be disabled. This patch introduces a deferral mechanism to remove this requirement. Signed-off-by: Jean-Baptiste Theou <jtheou@adeneo-embedded.us> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-06-22watchdog: docs: omap_wdt also understands nowayoutLars Poeschel
The omap_wdt kernel driver also understands the nowayout module parameter. This updates the watchdog-parameters.txt to reflect this fact. Signed-off-by: Lars Poeschel <poeschel@lemonage.de> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-09-26Documentation: use subdir-y to avoid unnecessary built-in.o filesPeter Foley
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>
2014-08-05Documentation: fix two typos in watchdog-api.txtSangjung Woo
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>
2014-03-31watchdog: it87_wdt: Work around non-working CIR interruptsMarc van der Wal
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>
2014-03-31watchdog: Add tegra watchdogAndrew Chew
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>
2013-07-11watchdog: delete mpcore_wdt driverViresh Kumar
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>
2013-03-01watchdog: core: dt: add support for the timeout-sec dt propertyFabio Porcedda
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>
2012-08-29watchdog: fix watchdog-test.c build warningRandy Dunlap
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>
2012-05-30Watchdog: DA9052/53 PMIC watchdog supportAshish Jangam
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>
2012-05-30watchdog: Add support for dynamically allocated watchdog_device structsHans de Goede
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>
2012-05-30watchdog: Add Locking supportHans de Goede
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>
2012-05-30watchdog: create all the proper device filesAlan Cox
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>
2012-05-30watchdog: Add multiple device supportAlan Cox
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>
2012-05-23Documentation/watchdog: Fix the file descriptor leak when no cmdline arg givenDevendra Naga
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>
2012-05-23Documentation/watchdog: close the fd when cmdline arg givenDevendra Naga
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>