watchdog: Convert GPL 2.0 notice to SPDX identifier

Convert the boilerplate to SPDX license identifier. While at it, also
move SPDX identifier for drivers/watchdog/rtd119x_wdt.c to the top of
file (as in other files).

Cc: Ray Lehtiniemi <rayl@mail.com>,
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Deepak Saxena <dsaxena@plexity.net>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Jonas Jensen <jonas.jensen@gmail.com>
Cc: Sylver Bruneau <sylver.bruneau@googlemail.com>
Cc: Denis Turischev <denis@compulab.co.il>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Ray Lehtiniemi <rayl@mail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lkml.kernel.org/r/20230517072140.1086660-2-bagasdotme@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: ts4800_wdt: Fix refcount leak in ts4800_wdt_probe

of_parse_phandle() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
Add missing of_node_put() in some error paths.

Fixes: bf9006399939 ("watchdog: ts4800: add driver for TS-4800 watchdog")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220511114203.47420-1-linmq006@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: ts4800_wdt: drop warning after registering device

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>

watchdog: ts4800_wdt: Convert to use device managed functions and other improvements

Use device managed functions to simplify error handling, reduce
source code size, improve readability, and reduce the likelyhood of bugs.
Other improvements as listed below.

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

- Drop assignments to otherwise unused variables
- Drop empty remove function
- Introduce local variable 'struct device *dev' and use it instead of
dereferencing it repeatedly
- Use devm_watchdog_register_driver() to register watchdog device

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

watchdog: ts4800: release syscon device node in ts4800_wdt_probe()

Put syscon device node when it is not needed anymore.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
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>

watchdog: ts4800: add driver for TS-4800 watchdog

This watchdog is instantiated in a FPGA that is memory mapped. It is
made of only one register, called the feed register. Writing to this
register will re-arm the watchdog for a given time (and enable it if it
was disable). It can be disabled by writing a special value into it.

It is part of a syscon block, and the watchdog register offset in this
block varies from board to board. This offset is passed in the syscon
property after the phandle to the syscon node.

Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>