watchdog: starfive: check watchdog status before enabling in system resume

System resume will start and enable watchdog regardless of whether the
watchdog is enabled/disabled during a system suspend.
Add a check to the watchdog status and only start and enable the
watchdog if the watchdog status is running/active.

Signed-off-by: Sia Jee Heng <jeeheng.sia@starfivetech.com>
Signed-off-by: Ji Sheng Teoh <jisheng.teoh@starfivetech.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240130055118.1917086-1-jisheng.teoh@starfivetech.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: starfive: Check pm_runtime_enabled() before decrementing usage counter

In the probe function, pm_runtime_put_sync() will fail on platform with
runtime PM disabled.
Check if runtime PM is enabled before calling pm_runtime_put_sync() to
fix it.

Fixes: db728ea9c7be ("drivers: watchdog: Add StarFive Watchdog driver")
Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
Signed-off-by: Ley Foon Tan <leyfoon.tan@starfivetech.com>
Signed-off-by: Ji Sheng Teoh <jisheng.teoh@starfivetech.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240119082722.1133024-1-jisheng.teoh@starfivetech.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: starfive: add lock annotations to fix context imbalances

Add the necessary __acquires() and __releases() to the functions
that take and release the wdt lock to avoid the following sparse
warnings:

drivers/watchdog/starfive-wdt.c:204:13: warning: context imbalance in 'starfive_wdt_unlock' - wrong count at exit
drivers/watchdog/starfive-wdt.c:212:9: warning: context imbalance in 'starfive_wdt_lock' - unexpected unlock

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20231122085118.177589-1-ben.dooks@codethink.co.uk
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: starfive-wdt: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20231106154807.3866712-5-u.kleine-koenig@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: starfive: Remove #ifdef guards for PM related functions

Use the new PM macros for the suspend and resume functions to be
automatically dropped by the compiler when CONFIG_PM or
CONFIG_PM_SLEEP are disabled, without having to use #ifdef guards.

This has the advantage of always compiling these functions in,
independently of any Kconfig option. Thanks to that, bugs and other
regressions are subsequently easier to catch.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230706082928.10869-1-paul@crapouillou.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: Explicitly include correct DT includes

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it was merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230726233302.3812749-1-robh@kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: starfive: Fix the warning of starfive_wdt_match

Drop the function of of_match_ptr() to fix the warning of unused variable
'starfive_wdt_match'.

Fixes: db728ea9c7be ("drivers: watchdog: Add StarFive Watchdog driver")
Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230427074400.55380-1-xingyu.wu@starfivetech.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: starfive: Fix the probe return error if PM and early_enable are both disabled

When the starfive watchdog driver uses 'pm_runtime_put_sync()' as probe
return value at last and 'early_enable' is disabled, it could return the
error '-ENOSYS' if the CONFIG_PM is disabled, but the driver should works
normally.

Drop the 'return' and keep the 'pm_runtime_put_sync()', but do not use it
as the return value.

Fixes: db728ea9c7be ("drivers: watchdog: Add StarFive Watchdog driver")
Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230426031216.37981-1-xingyu.wu@starfivetech.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

drivers: watchdog: Add StarFive Watchdog driver

Add watchdog driver for the StarFive JH7100 and JH7110 SoC.

Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230314132437.121534-3-xingyu.wu@starfivetech.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>