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# STM32 LPTIM configuration options

# Copyright (c) 2019 STMicroelectronics
# SPDX-License-Identifier: Apache-2.0

DT_CHOSEN_STDBY_TIMER := st,lptim-stdby-timer

menuconfig STM32_LPTIM_TIMER
	bool "STM32 Low Power Timer [EXPERIMENTAL]"
	default y
	depends on DT_HAS_ST_STM32_LPTIM_ENABLED
	depends on CLOCK_CONTROL && PM
	select TICKLESS_CAPABLE
	select EXPERIMENTAL
	help
	  This module implements a kernel device driver for the LowPower Timer
	  and provides the standard "system clock driver" interfaces.

if STM32_LPTIM_TIMER

choice STM32_LPTIM_CLOCK
	prompt "LPTIM clock value configuration"
	help
	  This option is deprecated and configuration of LPTIM domain clock
	  using devicetree should be preferred.

config STM32_LPTIM_CLOCK_LSI
	bool "LSI"
	help
	  Use LSI as LPTIM clock

config STM32_LPTIM_CLOCK_LSE
	bool "LSE"
	help
	  Use LSE as LPTIM clock

endchoice

config STM32_LPTIM_CLOCK
	int
	default 32768 if STM32_LPTIM_CLOCK_LSE
	default 32000 if STM32_LPTIM_CLOCK_LSI

config STM32_LPTIM_TIMEBASE
	hex "LPTIM AutoReload value"
	default 0xFFFF if STM32_LPTIM_CLOCK_LSE
	default 0xF9FF if STM32_LPTIM_CLOCK_LSI

config STM32_LPTIM_TICK_FREQ_RATIO_OVERRIDE
	bool "Override tick to freq ratio check"
	default y if ZTEST
	help
	  For LPTIM configuration, a specific tick freq is advised
	  depending on LPTIM input clock:
	  - LSI(32KHz): 4000 ticks/sec
	  - LSE(32678): 4096 ticks/sec
	  To prevent misconfigurations, a dedicated check is implemented
	  in the driver.
	  This options allows to override this check

config STM32_LPTIM_STDBY_TIMER
	bool "Use an additional timer while entering Standby mode"
	default $(dt_chosen_enabled,$(DT_CHOSEN_STDBY_TIMER))
	depends on COUNTER
	depends on TICKLESS_KERNEL
	select EXPERIMENTAL
	help
	  There are chips e.g. STM32WBAX family that use LPTIM as a system timer,
	  but LPTIM is not clocked in standby mode. These chips usually have
	  another timer that is not stopped, but it has lower frequency e.g.
	  RTC, thus it can't be used as a main system timer.

	  Use the Standby timer for timeout (wakeup) when the system is entering
	  Standby state.

	  The chosen Standby timer node has to support setting alarm from the
	  counter API.

endif # STM32_LPTIM_TIMER