clocksource/drivers/stm32-lp: Drop of_match_ptr for ID table

The driver can match only via the DT table so the table should be always
used and the of_match_ptr does not have any sense (this also allows ACPI
matching via PRP0001, even though it might not be relevant here).

drivers/clocksource/timer-stm32-lp.c:203:34: error: ‘stm32_clkevent_lp_of_match’ defined but not used [-Werror=unused-const-variable=]

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230311173803.263446-1-krzysztof.kozlowski@linaro.org

clocksource/drivers/timer-stm32-lp: Mark driver as non-removable

The comment in the remove callback suggests that the driver is not
supposed to be unbound. However returning an error code in the remove
callback doesn't accomplish that. Instead set the suppress_bind_attrs
property (which makes it impossible to unbind the driver via sysfs).
The only remaining way to unbind an stm32-lp device would be module
unloading, but that doesn't apply here, as the driver cannot be built as
a module.

Also drop the useless remove callback.

[dlezcano] : Fixed up the wrong function removed

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230313075430.2730803-3-u.kleine-koenig@pengutronix.de

clocksource: remove MODULE_LICENSE in non-modules

Since commit 8b41fc4454e ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations
are used to identify modules. As a consequence, uses of the macro
in non-modules will cause modprobe to misidentify their containing
object file as a module when it is not (false positives), and modprobe
might succeed rather than failing with a suitable error message.

So remove it in the files in this commit, none of which can be built as
modules.

Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: linux-modules@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Hitomi Hasegawa <hasegawa-hitomi@fujitsu.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: linux-stm32@st-md-mailman.stormreply.com
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

clocksource: Add Low Power STM32 timers driver

Implement clock event driver using low power STM32 timers.
Low power timer counters running even when CPUs are stopped.
It could be used as clock event broadcaster to wake up CPUs but not like
a clocksource because each it rise an interrupt the counter restart from 0.

Low power timers have a 16 bits counter and a prescaler which allow to
divide the clock per power of 2 to up 128 to target a 32KHz rate.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Pascal Paillet <p.paillet@st.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>