Shoud I set PM_DEVICE_ACTION_SUSPEND on I2C0 before sys_poweroff() ?

RE: Shoud I set PM_DEVICE_ACTION_SUSPEND on I2C0 before sys_poweroff() ?

JY wu — Mon, 07 Oct 2024 05:44:28 GMT

Hi, sorry for replying late.

My work around is :

remove CONFIG_PM_DEVICE_RUNTIME_EXCLUSIVE and CONFIG_PM_DEVICE_RUNTIME

As you said, this work around has trade off is to give up "automatic power management".

But, at this time, we have no better solutions.

RE: Shoud I set PM_DEVICE_ACTION_SUSPEND on I2C0 before sys_poweroff() ?

jeffryoliver — Mon, 07 Oct 2024 03:51:30 GMT

@ basket random: I agree with you

RE: Shoud I set PM_DEVICE_ACTION_SUSPEND on I2C0 before sys_poweroff() ?

Kazi Afroza Sultana — Tue, 20 Aug 2024 14:23:57 GMT

Hello,

So, your problem is solved in this way?

Usually CONFIG_PM_DEVICE_RUNTIME should be enabled when you use I2C device.

If both CONFIG_PM_DEVICE_RUNTIME and CONFIG_PM_DEVICE_RUNTIME_EXCLUSIVE are off, it means that the automatic power management handled by these configurations is not active. I think because of your application type this would work.

RE: Shoud I set PM_DEVICE_ACTION_SUSPEND on I2C0 before sys_poweroff() ?

JY wu — Sun, 11 Aug 2024 19:56:23 GMT

Hi~

Thanks for your efforts.

I tried to set CONFIG_PM_DEVICE_RUNTIME_EXCLUSIVE=n when CONFIG_PM_DEVICE_RUNTIME=y.

But still get ""Could not suspend I2C (-120)" when set I2C to PM_DEVICE_STATE_SUSPEND.

So I have to turn off CONFIG_PM_DEVICE_RUNTIME.

After set CONFIG_PM_DEVICE_RUNTIME=n , I get a yellow under line warning on CONFIG_PM_DEVICE_RUNTIME_EXCLUSIVE.

It says CONFIG_PM_DEVICE_RUNTIME_EXCLUSIVE is associated with CONFIG_PM_DEVICE_RUNTIME.

Finally, I remove CONFIG_PM_DEVICE_RUNTIME_EXCLUSIVE=n and CONFIG_PM_DEVICE_RUNTIME=n .

Now I can put I2C to PM_DEVICE_STATE_SUSPEND after remove CONFIG_PM_DEVICE_RUNTIME_EXCLUSIVE and CONFIG_PM_DEVICE_RUNTIME.

RE: Shoud I set PM_DEVICE_ACTION_SUSPEND on I2C0 before sys_poweroff() ?

Kazi Afroza Sultana — Fri, 09 Aug 2024 15:10:34 GMT

Hello,

''But I still don't know remove CONFIG_PM_DEVICE_RUNTIME has any portential disadvantage?''

This could potentially lead to conflicts if not managed properly.

If you want to use PM_DEVICE_ACTION_SUSPEND, you have to set CONFIG_PM_DEVICE_RUNTIME_EXCLUSIVE as ''n''. It is enabled by default when CONFIG_PM_DEVICE_RUNTIME is enabled. You have disabled CONFIG_PM_DEVICE_RUNTIME. So, I think it's ok.

you can read Device Runtime Power Management (nordicsemi.com) this documentation.

RE: Shoud I set PM_DEVICE_ACTION_SUSPEND on I2C0 before sys_poweroff() ?

JY wu — Wed, 31 Jul 2024 14:29:23 GMT

Hi~

Yes, I had add CONFIG_PM_DEVICE=y in prj.conf,

At first, I add these lines:

CONFIG_PM_DEVICE=y

CONFIG_PM_DEVICE_RUNTIME=y

CONFIG_POWEROFF=y

Since "CONFIG_PM_DEVICE_RUNTIME=y" conflicts with PM_DEVICE_ACTION_SUSPEND, I remove it.

There are two relative setting left now:

CONFIG_PM_DEVICE=y

CONFIG_POWEROFF=y

After remove "CONFIG_PM_DEVICE_RUNTIME", I2c can be.SUSPEND successfully.

But I still don't know remove CONFIG_PM_DEVICE_RUNTIME has any portential disadvantage?

RE: Shoud I set PM_DEVICE_ACTION_SUSPEND on I2C0 before sys_poweroff() ?

Kazi Afroza Sultana — Wed, 31 Jul 2024 13:59:20 GMT

Hello,

It is recommended to suspend the I2C device before calling sys_poweroff().

Did you add CONFIG_PM_DEVICE=y in prj.conf file?

TWI shares registers and other resources with other peripherals that have the same ID as TWI.

Therefore, you must disable all peripherals that have the same ID as TWI before TWI can be configured and used. Disabling a peripheral that has the same ID as TWI will not reset any of the registers that are shared with TWI. It is therefore important to configure all relevant TWI registers explicitly to secure that it operates correctly.

You can check if SDA and SCL pins of I2C are not used for other peripherals.

RE: Shoud I set PM_DEVICE_ACTION_SUSPEND on I2C0 before sys_poweroff() ?

JY wu — Wed, 31 Jul 2024 07:06:03 GMT

Hi!

Thanks for your suggestion.

We copy paste your code , but build failed.

Error Message : undefined reference to `pm_device_state_set'

Mabye we need another include file, so we add

#include <zephyr/pm/pm.h>

but not works, still get error message undefined reference to `pm_device_state_set' when build code.

VS code IDE intellisense list all functions starts with "pm_device_state", but only "pm_device_state_get" found, no "pm_device_state_set".

And we find out that, set

CONFIG_PM_DEVICE_RUNTIME=y

makes rc always return -120 in the following code.

int rc = pm_device_action_run(i2c_dev, PM_DEVICE_ACTION_SUSPEND);

After change "CONFIG_PM_DEVICE_RUNTIME=n " to "n", then return value rc become 0, and PM_DEVICE_ACTION_SUSPEND successed.

Does set "CONFIG_PM_DEVICE_RUNTIME" to "n" has any disadvantage ?

RE: Shoud I set PM_DEVICE_ACTION_SUSPEND on I2C0 before sys_poweroff() ?

jeffryoliver — Wed, 31 Jul 2024 03:28:50 GMT

Hello, I think the error code -120 you are receiving when trying to suspend the I2C device indicates that the suspend action failed. This might be due to various reasons such as incorrect configuration or conflicts with other operations.
While some peripherals might be automatically handled during system shutdown, it's still recommended to properly manage the power state of peripherals like I2C to ensure data integrity and proper power management.

I think you should test both scenarios - with and without explicitly suspending I2C - to see if there are any differences in power consumption or behavior during system shutdown.
Code Modification:

c
const struct device *const i2c_dev = DEVICE_DT_GET(DT_NODELABEL(i2c0));

int rc = pm_device_state_set(i2c_dev, PM_DEVICE_STATE_SUSPEND);

if (rc < 0) {
printf("Could not suspend I2C (%d)\n", rc);
return 0;
}

sys_poweroff();

By explicitly suspending the I2C device before calling sys_poweroff(), you ensure that the I2C peripheral is properly handled before system shutdown. This aligns with best practices for power management and can help avoid potential issues related to data integrity or power consumption.