STM32WL ADC doesn't work with power management

[honestech74]

Describe the bug
If enabled CONFIG_ADC and CONFIG_PM, you can read just once using adc_read(), then Zephyr halts.

To Reproduce
Steps to reproduce the behavior:

1. add the nucleo_wl55jc.overlay to samples/drivers/adc/boards

/ {
	zephyr,user {
		io-channels = <&adc1 11>;
	};
};

&adc1 {
	pinctrl-0 = <&adc_in11_pa15>;
	status = "okay";
};

2. add configs to the sample project

CONFIG_PM=y

3. build and flash with nucleo_wl55jc board
4. see the log

Expected behavior
It should show the ADC reading every second.

Logs and console output
Before enabled CONFIG_PM, could see the ADC value every second.
After enabled CONFIG_PM, only could see the ADC value one time, then not running.

Environment (please complete the following information):

• Ubuntu 18.04
• Toolchain: 0.12.4
• Zephyr v2.6.99

[UPDATED]

• Zephyr commit SHA-1: 57690f5

[FRASTM]

There is only a AN5568 . Could the situation apply in this sample ?
"The STM32WL devices embed a multiple 12-bit/2.50 Msps ADC. This very fast and accurate converter can jeopardize the battery lifetime if left powered-up. As the ADC consumption is roughly proportional to the acquisition frequency (around 200 μA/Msps), from a consumption standpoint, the application can choose between the following solutions:
– Perform the acquisition at low speed to limit the maximum current.
– Perform the acquisition at the maximum speed to switch back to ultra-low-power mode quickly.
When the acquisition is performed slowly, the ADC consumption itself can go down to few tens of a μA, drastically limiting the maximum current. This may be mandatory when the power source provides a limited current. If the CPU has no other task to perform during that time, this slow acquisition increases the time spent by the system in Run, Sleep, LPRun or LPSleep mode, versus the time spent in Stop or Standby ultra-low-power mode."

Otherwise, even if the stm32wl is close to the stm32wb serie, the sequence to switch to HSI before entering Stop Mode is not mentioned for the stm32wlx. When testing, the samples/drivers/adc on nucleo_wb55rg with CONFIG_PM is correct.

[ABOSTM]

Zephyr v2.6.99 doesn't exist. Do you mean 1.6.99 ?
I tested on my side and it is working well:
board: nucleo_wl55jc
sha1 : 17d2e9d
I follow your To Reproduce steps

[FRASTM]

@honestech74 Can you confirm that you have the power.c for the ./soc/arm/st_stm32/stm32wl
--> the PR #36574 has introduced the power management for the stm32wl soc serie.

[honestech74]

Zephyr v2.6.99 doesn't exist. Do you mean 1.6.99 ?

@ABOSTM Sorry for the confusing version. I am in master branch and you can check the version from this file.
https://github.com/zephyrproject-rtos/zephyr/blob/main/VERSION#L1-L5
Also commit SHA1: 57690f5

Can you confirm that you have the power.c for the ./soc/arm/st_stm32/stm32wl

@FRASTM Sure, I have it and it works well for boards/stm32/power_mgmt/blinky

[honestech74]

Zephyr v2.6.99 doesn't exist. Do you mean 1.6.99 ?
I tested on my side and it is working well:
board: nucleo_wl55jc
sha1 : 17d2e9d
I follow your To Reproduce steps

@ABOSTM I have double checked on your commit sha, but couldn't get running.
If you followed Reproduce and got running, please check your SHA. I guess you are in another branch or miss CONFIG_PM?
I have another issue on I2C with CONFIG_PM.

[EDIT] it's my git HEAD for checking.

$ git rev-parse --short HEAD
17d2e9d084

[ABOSTM]

@honestech74 ,
Let me change a bit the status of my tests:
After flashing the board (west flash with openOCD), it is working fine, even after pressing reset button, it works
But if I unplug and replug the board (ST-link usb powered), then it fails, ADC reading: xxx Displayed only once in console.

[honestech74]

@ABOSTM
You are right, I can see it's running when flash using stm32cubeprogrammer with openocd, but stopped after unplug and replug.
Even if it's running, getting 1.2mA power consumption and there are high peaks every a second(there is k_msleep(1000) in sample) Is it reasonable? I guess it might be about a few hundreds of uA in average.

I'd like to use J-Link so tested with it until now. It's stopped after show one ADC log.
I never saw this difference between programmers, I can't trust the result when using stm32cubeprogrammer.

[honestech74]

@ABOSTM Can you test it using J-Link? It seems like there is something wrong in ADC driver. I've tested ADC without CONFIG_PM but stopped SoC using LL library and init the clock after wake up. But it's not running after wake up.