ryzen_smu prevents full suspend on Ryzen AI 9 HX 370 (high battery drain)

[clsv]

Hi,

My system:
Laptop: ASUS Zephyrus G14 (2025)
CPU: AMD Ryzen AI 9 HX 370 w/ Radeon 890M
OS: Linux

I noticed abnormal battery drain while the laptop is in suspend mode. The system appears to enter suspend, but battery usage is much higher than expected.

Using amd-debug-tools, I investigated the suspend state and found that the laptop does not fully transition into a proper low-power sleep state.

After some trial and error, I found that if I unload the ryzen_smu kernel module before suspend, the laptop sleeps correctly and the battery drain stops.

Reproducible behavior:

ryzen_smu loaded
Suspend laptop
Significant battery drain during suspend

Workaround:

sudo modprobe -r ryzen_smu
Suspend once
After resume, the issue is gone
ryzen_smu can be loaded again, and future suspends still work normally

I use a systemd sleep hook:
/lib/systemd/system-sleep/ryzen_smu.sh

#!/bin/bash

case "$1" in
    pre)
        modprobe -r ryzen_smu
        ;;
    post)
        modprobe ryzen_smu
        ;;
esac

This suggests the module may be preventing the platform from reaching deeper suspend states on this hardware generation.

[amkillam]

Interesting. Had you used the driver at all?

There are RSMU commands that can disable usage of power states, for example, in favor of manual frequency and voltage settings. If you used the driver to set your CPU frequency or voltage, or used another application which would do so otherwise (e.g. ryzenadj), that would be an obvious cause. Otherwise this would need investigation.

[amkillam]

Interesting. Had you used the driver at all?

There are RSMU commands that can disable usage of power states, for example, in favor of manual frequency and voltage settings. If you used the driver to set your CPU frequency or voltage, or used another application which would do so otherwise (e.g. ryzenadj), that would be an obvious cause. Otherwise this would need investigation.

Though this wouldn't explain why module unload resolved the issue.

[clsv]

Though this wouldn't explain why module unload resolved the issue.

I am using ryzenadj with your kernel module, and I have Secure Boot enabled

[jetlego]

I encountered this issue as well on a Ryzen 7640u system. I get Did not reach hardware sleep state anytime when running amd-s2idle test with the module loaded at boot.

Running amd-s2idle test after a modprobe -r ryzen_smu does result in the device reaching hardware sleep. Oddly enough, if I wait some time and then run modprobe ryzen_smu to load the module again, amd-s2idle test reports that hardware sleep was reached again. Here's the amd-s2idle report after reloading the module: After second modprobe.txt

Some additional context from a framework community support thread: https://community.frame.work/t/fw13-7640u-not-reaching-hardware-sleep-state/82600/8

[jcdutton]

To support suspend / resume. You only need to add the suspend / resume callbacks to the kernel driver.