Commit Graph

14 Commits

Author SHA1 Message Date
Rasmus Villemoes bc137dfdbe watchdog: gpio_wdt: set WDOG_HW_RUNNING in gpio_wdt_stop
The first patch above (https://patchwork.kernel.org/patch/9970181/)
makes the oops go away, but it just papers over the problem. The real
problem is that the watchdog core clears WDOG_HW_RUNNING in
watchdog_stop, and the gpio driver fails to set it in its stop
function when it doesn't actually stop it. This means that the core
doesn't know that it now has responsibility for petting the device, in
turn causing the device to reset the system (I hadn't noticed this
because the board I'm working on has that reset logic disabled).

How about this (other drivers may of course have the same problem, I
haven't checked). One might say that ->stop should return an error
when the device can't be stopped, but OTOH this brings parity between
a device without a ->stop method and a GPIO wd that has always-running
set. IOW, I think ->stop should only return an error when an actual
attempt to stop the hardware failed.

From: Rasmus Villemoes <rasmus.villemoes@prevas.dk>

The watchdog framework clears WDOG_HW_RUNNING before calling
->stop. If the driver is unable to stop the device, it is supposed to
set that bit again so that the watchdog core takes care of sending
heart-beats while the device is not open from user-space. Update the
gpio_wdt driver to honour that contract (and get rid of the redundant
clearing of WDOG_HW_RUNNING).

Fixes: 3c10bbde10 ("watchdog: core: Clear WDOG_HW_RUNNING before calling the stop function")
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
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>
2017-12-28 20:45:36 +01:00
Linus Walleij a2363f9d2f watchdog: gpio: Convert to use GPIO descriptors
This converts the GPIO watchdog driver to use GPIO descriptors
instead of relying on the old method to read out GPIO numbers
from the device tree and then using those with the old GPIO
API.

The descriptor API keeps track of whether the line is active
low so we can remove all active low handling and rely on the
GPIO descriptor to deal with this for us.

Signed-off-by: Linus Walleij <linus.walleij@linaro.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>
2017-12-28 20:44:57 +01:00
Linus Walleij d0d0677e8f watchdog: gpio: Add some local helper variables
This add "dev" and "np" variables to make the probe() function
a bit easier to read.

Signed-off-by: Linus Walleij <linus.walleij@linaro.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>
2017-12-28 20:44:56 +01:00
Guenter Roeck 03bca15833 watchdog: gpio: Convert to use infrastructure triggered keepalives
The watchdog infrastructure now supports handling watchdog keepalive
if the watchdog is running while the watchdog device is closed.
The infrastructure now also supports generating additional heartbeats
if the maximum hardware timeout is smaller than or close to the
configured timeout. Convert the driver to use this infrastructure.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2017-06-05 20:39:27 +02:00
Wei Yongjun 1ac0656343 watchdog: gpio_wdt: Fix missing platform_set_drvdata() in gpio_wdt_probe()
Add missing platform_set_drvdata() in gpio_wdt_probe(), otherwise
calling platform_get_drvdata() in remove returns NULL.

This is detected by Coccinelle semantic patch.

Signed-off-by: Wei Yongjun <weiyj.lk@gmail.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>
2016-07-27 10:47:43 +02:00
Guenter Roeck 8a7b76be69 watchdog: gpio: Do not use device pointer from struct watchdog_device
The device pointer in struct watchdog_device has a different lifetime
than the driver code and should not be used in drivers. Use the pointer
to the parent device instead.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-12-28 23:04:05 +01:00
Damien Riegel 28e805b44d watchdog: gpio_wdt: use core reboot notifier
Get rid of the custom reboot notifier block registration and use the one
provided by the watchdog core.

Note that this watchdog used to stop unconditionnaly on SYS_HALT and
SYS_POWER_OFF. The core function now calls ops->stop on SYS_HALT and
SYS_DOWN. To prevent the watchdog from being stopped on reboot, the
"always-running" property must be set, otherwise it will now be stopped.

Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirlinux.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>
2015-12-13 15:56:02 +01:00
Pratyush Anand 6551881c86 Watchdog: Fix parent of watchdog_devices
/sys/class/watchdog/watchdogn/device/modalias can help to identify the
driver/module for a given watchdog node. However, many wdt devices do not
set their parent and so, we do not see an entry for device in sysfs for
such devices.

This patch fixes parent of watchdog_device so that
/sys/class/watchdog/watchdogn/device is populated.

Exceptions: booke, diag288, octeon, softdog and w83627hf -- They do not
have any parent. Not sure, how we can identify driver for these devices.

Signed-off-by: Pratyush Anand <panand@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Maxime Coquelin <maxime.coquelin@st.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-09-09 21:39:22 +02:00
Uwe Kleine-König 4f2d0b2d1b watchdog: gpio-wdt: ping already at startup for always running devices
During probe for an always-running watchdog a timer is setup to
constantly ping the watchdog while the device is not open. The gpio to
ping the watchdog is setup to inactive.

For a watchdog with hw_algo = "toggle" this results in a ping depending
on the initial state of the gpio, for hw_algo = "level" no ping is
generated.

Make sure that the first automatic ping is sent immediately and not only
when the timer expires the first time. This makes the machine survive in
case more than half of the watchdog timeout is already elapsed. (Which
is very probable for the chip I'm faced with that has a timeout of one
second.)

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-09-09 21:35:37 +02:00
Uwe Kleine-König 0a0a542f6b watchdog: gpio-wdt: be more strict about hw_algo matching
strncmp(algo, "toggle", 6) doesn't compare the trailing '\0' byte, so
using

	hw_algo = "toggleboggle"

is recognized the same way as

	hw_algo = "toggle"

. While this doesn't introduce any problems for a device tree that
sticks to the documented settings it's still ugly.

Fix this by using strcmp to only match on "toggle" and "level".

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-09-09 21:35:14 +02:00
Jean-Baptiste Theou 5e53c8ed81 watchdog: gpio_wdt: Add option for early registration
In some situation, mainly when it's not possible to disable a
watchdog, you may want the watchdog driver to be started as soon
as possible.

Adding GPIO_WATCHDOG_ARCH_INITCALL to raise initcall from
module_init to arch_initcall.

This patch require watchdog registration deferral mechanism

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>
2015-06-29 11:51:08 +02:00
Mike Looijmans ba804a9510 watchdog: gpio_wdt: Add "always_running" feature to GPIO watchdog
On some chips, like the TPS386000, the trigger cannot be disabled
and the CPU must keep toggling the line at all times. Add a switch
"always_running" to keep toggling the GPIO line regardless of the
state of the soft part of the watchdog. The "armed" member keeps
track of whether a timeout must also cause a reset.

Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-02-17 21:33:22 +01:00
Wolfram Sang fa21a580de watchdog: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:21:56 +02:00
Alexander Shiyan 25134eafb0 watchdog: GPIO-controlled watchdog
This patch adds a watchdog driver for devices controlled through GPIO,
(Analog Devices ADM706, Maxim MAX823, National NE555 etc).

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-01-28 21:21:02 +01:00