Machine resets via da9062/da9063 PMICs are challenging since one needs
to use special i2c atomic transfers due to the fact interrupts are
disabled in such late system stages. This is the reason both PMICs don't
use regmap and have instead opted for i2c_smbus_write_byte_data() in
restart handlers.
However extensive testing revealed that even using atomic safe function
is not enough and occasional resets fail with error message "Failed to
shutdown (err = -11)". This is due to the fact that function
i2c_smbus_write_byte_data() in turn calls __i2c_lock_bus_helper()
which might fail with -EAGAIN when bus lock is already taken and cannot
be released anymore.
Thus replace i2c_smbus_write_byte_data() with unlocked flavor of
i2c_smbus_xfer() function to avoid above dead-lock scenario. At this
system stage we don't care about proper locking anymore and only want
proper machine reset to be carried out.
Signed-off-by: Primoz Fiser <primoz.fiser@norik.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20221216083645.2574077-1-primoz.fiser@norik.com
[groeck: Fixed continuation line alignment]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Proper machine resets via da9062/da9063 PMICs are very tricky as they
require special i2c atomic transfers when interrupts are not available
anymore. This is also a reason why both PMIC's restart handlers do not
use regmap but instead opt for i2c_smbus_write_byte_data() which does
i2c transfer in atomic manner. Under the hood, this function tries to
obtain i2c bus lock with call to i2c_adapter_trylock_bus() which will
return -EAGAIN (-11) if lock is not available.
Since commit 982bb70517 ("watchdog: reset last_hw_keepalive time at
start") occasional restart handler failures with "Failed to shutdown
(err = -11)" error messages were observed, indicating that some
process is holding the i2c bus lock. Investigation into the matter
uncovered that sometimes during reboot sequence watchdog ping is issued
late into poweroff/reboot phase which did not happen before mentioned
commit (usually the watchdog ping happened immediately as commit message
suggests). As of now, when watchdog ping usually happens late into
poweroff/reboot stage when interrupts are not available anymore, i2c bus
lock cannot be released anymore and pending restart handler in turn
fails.
Thus, to prevent such late watchdog pings from happening ahead of
pending machine restart and consequently locking up the i2c bus, check
for system_state in watchdog ping handler and consequently do not send
pings anymore in case system_state > SYSTEM_RUNNING.
Signed-off-by: Primoz Fiser <primoz.fiser@norik.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Link: https://lore.kernel.org/r/20210708082128.2832904-1-primoz.fiser@norik.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
There is actually no need to ping the watchdog before disabling it
during timeout change. Disabling the watchdog already takes care of
resetting the counter.
This fixes an issue during boot when the userspace watchdog handler takes
over and the watchdog is already running. Opening the watchdog in this case
leads to the first ping and directly after that without the required
heartbeat delay a second ping issued by the set_timeout call. Due to the
missing delay this resulted in a reset.
Signed-off-by: Stefan Riedmueller <s.riedmueller@phytec.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Link: https://lore.kernel.org/r/20200403130728.39260-3-s.riedmueller@phytec.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
During probe try to set the timeout from device tree and fall back to
either the pre-configured timeout set by e.g. the bootloader in case the
watchdog is already running or the default value.
If the watchdog is already running make sure to update the timeout and
tell the framework about the running state to make sure the watchdog is
handled correctly until user space takes over. Updating the timeout also
removes the need for an additional manual ping so we can remove that as
well.
Signed-off-by: Stefan Riedmueller <s.riedmueller@phytec.de>
Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200403130728.39260-1-s.riedmueller@phytec.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
This fixes commit f6c98b0838 ("watchdog: da9062: add power management
ops"). During discussion [1] we agreed that this should be configurable
because it is a device quirk if we can't use the hw watchdog auto
suspend function.
[1] https://lore.kernel.org/linux-watchdog/20191128171931.22563-1-m.felsch@pengutronix.de/
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Fixes: f6c98b0838 ("watchdog: da9062: add power management ops")
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Link: https://lore.kernel.org/r/20200207071518.5559-1-m.felsch@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
The da9062 hw has a minimum ping cool down phase of at least 200ms. The
driver takes that into account by setting the min_hw_heartbeat_ms to
300ms and the core guarantees that the hw limit is observed for the
ping() calls. But the core can't guarantee the required minimum ping
cool down phase if a stop() command is send immediately after the ping()
command. So it is not allowed to ping the watchdog within the stop()
command as the driver does. Remove the ping can be done without doubts
because the watchdog gets disabled anyway and a (re)start resets the
watchdog counter too.
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200120091729.16256-1-m.felsch@pengutronix.de
[groeck: Updated description]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
The restart handler is executed during the shutdown phase which is
atomic/irq-less. The i2c framework supports atomic transfers since
commit 63b96983a5 ("i2c: core: introduce callbacks for atomic
transfers") to address this use case. Using regmap within an atomic
context is allowed only if the regmap type is MMIO and the cache type
'flat' or no cache is used. Using the i2c_smbus_write_byte_data()
function can be done without additional tests because:
1) the DA9062 is an i2c-only device and
2) the i2c framework emulates the smbus protocol if the host adapter
does not support smbus_xfer by using the master_xfer.
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Stefan Lengfeld <contact@stefanchrist.eu>
Tested-by: Stefan Lengfeld <contact@stefanchrist.eu>
Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Link: https://lore.kernel.org/r/20200115162307.7336-1-m.felsch@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Disable the watchdog during suspend if it is enabled and re-enable it on
resume. So we can sleep without the interruptions.
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191128171931.22563-1-m.felsch@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
The core will print out details now.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Introduce local variable 'struct device *dev' and use it instead of
dereferencing it repeatedly. Also replace 'ret = func(); return ret;'
with 'return func();'.
The conversion was done automatically with coccinelle using the
following semantic patches. The semantic patches and the scripts
used to generate this commit log are available at
https://github.com/groeck/coccinelle-patches
Cc: Support Opensource <support.opensource@diasemi.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
The patch "watchdog: da9062: use protection delay mechanism from core"
(fb484262) removed the only user of j_time_stamp. This turned into some
leftover functions that are removed with this patch.
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
This patch removes the windows protection routine that got
now covered by the wdt core.
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
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>
The DA9062 watchdog occasionally enters error condition and resets the
system if the timeout is changed quickly after the timer was enabled.
The method of disabling and waiting for > 150 µs before setting the
new timeout is taken from the DA9052 driver.
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
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>
Register a restart handler for the da9062 watchdog. System restart is
triggered by sending the shutdown command to the PMIC.
As more-suitable restart handlers may exist, the priority of the
watchdog restart handler is set to 128.
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
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>
Use device managed functions to simplify error handling, reduce
source code size, improve readability, and reduce the likelyhood of bugs.
The conversion was done automatically with coccinelle using the
following semantic patches. The semantic patches and the scripts used
to generate this commit log are available at
https://github.com/groeck/coccinelle-patches
- Replace 'val = e; return val;' with 'return e;'
- Drop assignments to otherwise unused variables
- Drop remove function
- Drop dev_set_drvdata()
- Use devm_watchdog_register_driver() to register watchdog device
Acked-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The of_device_id match array is added to support "dlg,da9062-watchdog"
as a valid .compatible string. A MODULE_DEVICE_TABLE() macro is added.
This patch assumes the use of a DA9062 fallback compatible string for the
DTS to pick up the DA9062 device driver for use with the DA9061 watchdog
hardware
Copyright header is updated to add DA9061 in its description and the module
description macro is extended to include DA9061.
Kconfig is updated to reflect support for DA9061/62.
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
/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>
Add watchdog driver support for DA9062
Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Primoz Fiser