watchdog: mlx_wdt: fix all kernel-doc warnings

Correct kernel-doc warnings as reported by kernel test robot:

mlx_wdt.c:56: warning: Function parameter or member 'wdt_type' not described in 'mlxreg_wdt'
mlx_wdt.c:56: warning: Excess struct member 'device' description in 'mlxreg_wdt'
mlx_wdt.c:56: warning: Excess struct member 'timeout' description in 'mlxreg_wdt'
mlx_wdt.c:56: warning: Excess struct member 'wd_type' description in 'mlxreg_wdt'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202312171701.xNkzdgdi-lkp@intel.com/
Cc: Michael Shych <michaelsh@nvidia.com>
Cc: Wim Van Sebroeck <wim@linux-watchdog.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-watchdog@vger.kernel.org
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20231218062659.26916-1-rdunlap@infradead.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: mlx-wdt: Parameter desctiption warning fix

Add parameter desription to fix warning.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202310241044.lvqeOGli-lkp@intel.com
Signed-off-by: Michael Shych <michaelsh@nvidia.com>
Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20231026082558.12142-1-michaelsh@nvidia.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: mlx-wdt: Use regmap_write_bits()

Use the regmap_write_bits() macro instead of regmap_update_bits_base().
No functional change.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210907092732.31815-1-p.zabel@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: mlx-wdt: support new watchdog type with longer timeout period

New programmable logic device can have watchdog type 3 implementation.
It's same as Type 2 with extended maximum timeout period.
Maximum timeout is up-to 65535 sec.
Type 3 HW watchdog implementation can exist on all Mellanox systems.
It is differentiated by WD capability bit.

Signed-off-by: Michael Shych <michaelsh@mellanox.com>
Reviewed-by: Vadim Pasternak <vadimp@mellanox.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200504141427.17685-4-michaelsh@mellanox.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: mlx_wdt: Use 'dev' instead of dereferencing it repeatedly

Introduce local variable 'struct device *dev' and use it instead of
dereferencing it repeatedly.

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

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: mlx-wdt: introduce a watchdog driver for Mellanox systems.

Introduce watchdog driver for a various range of Mellanox Ethernet and
Infiniband switch systems.

Watchdog driver for Mellanox watchdog devices, implemented in
programmable logic device.

Main and auxiliary watchdog devices can exist on the same system.
There are several actions that can be defined in the watchdog:
system reset, start fans on full speed and increase a counter.
The last 2 actions are performed without a system reset.
Actions without reset are provided for auxiliary watchdog devices,
which is optional.
Access to HW registers is performed through generic
regmap interface.

There are 2 types of HW watchdog implementations.
Type 1: actual HW timeout can be defined as power of 2 msec.
e.g. timeout 20 sec will be rounded up to 32768 msec.;
maximum timeout period is 32 sec (32768 msec.);
get time-left isn't supported
Type 2: actual HW timeout is defined in sec. and it's the same as
user-defined timeout;
maximum timeout is 255 sec;
get time-left is supported;

Watchdog driver is probed from the common mlx_platform driver.

Signed-off-by: Michael Shych <michaelsh@mellanox.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@linux-watchdog.org>