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: rtd119x: Use devm_clk_get_enabled() helper

The devm_clk_get_enabled() helper:
- calls devm_clk_get()
- calls clk_prepare_enable() and registers what is needed in order to
call clk_disable_unprepare() when needed, as a managed resource.

This simplifies the code and avoids the need of a dedicated function used
with devm_add_action_or_reset().

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/14b521b821279bc5111dc80b55d0936c5767c737.1672418470.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: rtd119x: drop unused module.h include

The Kconfig for this driver is:

config RTD119X_WATCHDOG
bool "Realtek RTD118x/RTD129x watchdog support"

...and hence it doesn't need to include module.h for anything.
There are no other signs of unused modular infrastructure.

Cc: Wim Van Sebroeck <wim@linux-watchdog.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-watchdog@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.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>

watchdog: rtd119x_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 unnecessary braces around conditional return statements
- Drop empty remove function
- Use devm_add_action_or_reset() for calls to clk_disable_unprepare
- Replace 'of_clk_get(np, 0)' with 'devm_clk_get(dev, NULL)'
- 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: rtd119x_wdt: Fix remove function

The driver registers the watchdog with devm_watchdog_register_device() but
still calls watchdog_unregister_device() on remove. Since clocks have to
be stopped when removing the driver, after the watchdog device has been
unregistered, we can not drop the call to watchdog_unregister_device().
Use watchdog_register_device() to register the watchdog.

Fixes: 2bdf6acbfead7 ("watchdog: Add Realtek RTD1295")
Cc: Andreas Färber <afaerber@suse.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: Convert to use devm_platform_ioremap_resource

Use devm_platform_ioremap_resource to reduce source code size,
improve readability, and reduce the likelyhood of bugs.

The conversion was done automatically with coccinelle using the
following semantic patch.

@r@
identifier res, pdev;
expression a;
expression index;
expression e;
@@

<+...
- res = platform_get_resource(pdev, IORESOURCE_MEM, index);
- a = devm_ioremap_resource(e, res);
+ a = devm_platform_ioremap_resource(pdev, index);
...+>

@depends on r@
identifier r.res;
@@
- struct resource *res;
... when != res

@@
identifier res, pdev;
expression index;
expression a;
@@
- struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, index);
- a = devm_ioremap_resource(&pdev->dev, res);
+ a = devm_platform_ioremap_resource(pdev, index);

Cc: Joel Stanley <joel@jms.id.au>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: Keguang Zhang <keguang.zhang@gmail.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Avi Fishman <avifishman70@gmail.com>
Cc: Nancy Yuen <yuenn@google.com>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Sylvain Lemieux <slemieux.tyco@gmail.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Barry Song <baohua@kernel.org>
Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Marc Gonzalez <marc.w.gonzalez@free.fr>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Tested-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Acked-by: Michal Simek <michal.simek@xilinx.com> (cadence/xilinx wdts)
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

watchdog: Add Realtek RTD1295

Add a watchdog driver for the Realtek RTD1295 SoC.

Based on QNAP's arch/arm/mach-rtk119x/driver/rtk_watchdog.c code and
mach-rtk119x/driver/dc2vo/fpga/include/iso_reg.h register defines.

Signed-off-by: Andreas Färber <afaerber@suse.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>