power management : build failure on stm32u083_dk board

[djiatsaf-st]

Describe the bug

There is a build failure on STM32U0 boards for power management samples.

This issue was introduced with the addition of PM support on STM32U0 boards through this PR: #88963.

The build error suggests using devicetree instead of the deprecated Kconfig option.

Regression

• This is a regression.

Steps to reproduce

1. Go to zephyr workspace
2. run with west:
   west build -p -b stm32u083c_dk/stm32u083xx samples/boards/st/power_mgmt/blinky -T sample.boards.stm32.power_mgmt.blinky
3. or run with twister :
   ./scripts/twister -p stm32u083c_dk -T samples/boards/st/power_mgmt/blinky/
4. see log output

Relevant log output

/zephyrproject/zephyr/drivers/timer/stm32_lptim_timer.c:34:2: error: #warning Kconfig for LPTIM source clock (LSI/LSE) is deprecated, use device tree. [-Werror=cpp]
   34 | #warning Kconfig for LPTIM source clock (LSI/LSE) is deprecated, use device tree.
      |  ^~~~~~~

Impact

Annoyance – Minor irritation; no significant impact on usability or functionality.

Environment

• OS: Linux ubuntu

• Toolchain: Zephyr SDK 0.17.O

• Zephyr version: v4.1.99

Additional Context

No response

[mickael868]

Before the PR #88963, CONFIG_PM was silently ignored.

Now that the PR declares select HAS_PM, PM is looking for stm32_lp_tick_source but is is not defined. I think that the fix is to add something similar to this in boards/st/stm32u083c_dk/stm32u083c_dk.dts:

stm32_lp_tick_source: &lptim2 {
  clocks = <&rcc STM32_CLOCK(APB1, 30U)>,
           <&rcc STM32_SRC_LSI LPTIM2_SEL(1)>;
  status = "okay";
};

I don't have this board and I prefer not to add code I can't test.