power: reset: rmobile-reset: Make sysc_base2 local

The static global variable sysc_base2 is no longer used outside the
probe method and the reset handler, so it can be converted to a local
variable, and passed to the reset handler via its callback data.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/35f04935c48ae55dc562071e0a1d6fca65234a58.1708944642.git.geert+renesas@glider.be
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: reset: rmobile-reset: Map correct MMIO resource

The registers related to reset generation are located in the second
register block. However, the conversion to device life-cycle managed
ioremap function accidentally changed the mapping to the first register
block.

Fixes: 0867276eb12230a5 ("power: reset: rmobile-reset: Use devm_platform_ioremap_resource() helper")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/3b267fb1b303f63248934a1a77bee319e1c44879.1708458882.git.geert+renesas@glider.be
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: reset: rmobile-reset: Use devm_register_sys_off_handler(RESTART)

Use device life-cycle managed register function to simplify probe and
exit paths.

Signed-off-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20240212162831.67838-11-afd@ti.com
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: reset: rmobile-reset: Use devm_platform_ioremap_resource() helper

Use device life-cycle managed ioremap function to simplify probe and
exit paths.

Signed-off-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20240212162831.67838-10-afd@ti.com
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: reset: rmobile-reset: 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>
Link: https://lore.kernel.org/r/20231104211501.3676352-28-u.kleine-koenig@pengutronix.de
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: reset: convert to SPDX identifiers

This patch updates license to use SPDX-License-Identifier
instead of verbose license text.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

power: reset: Add reset driver for R-Mobile platforms

Add a reset driver for Renesas R-Mobile and SH-Mobile SoCs. It registers
a restart handler to trigger a soft power-on reset through the R-Mobile
System Controller.
The priority of this restart handler is 192, to allow a watchdog driver
to use priority 128.

Note that we do not use syscon-reboot, as the HPB (Peripheral Bus
Bridge) semaphore should be acquired on systems where both the ARM and
SH core are in use. The driver can be extended later to support this,
when needed.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sebastian Reichel <sre@kernel.org>