feat(usb_host): esp sleep modes verification

[peter-marcisovsky]

Description

Verification of using light sleep and deep sleep in combination with USB Host application.

Light sleep

• Using CONFIG_ESP_SLEEP_EVENT_CALLBACKS
• Register enter and exit light sleep events
• Calling root port suspend/resume upon enter/exit light sleep to effectively suspend the peripheral and the connected device
• Connected device enters suspended state during the light sleep
• Connected device must not undergo a reset during light sleep

Light sleep log, with light sleep callbacks enabeld

Root port enters suspended mode before entering light sleep

Light sleep log, with light sleep callbacks disabled

Missing suspend/resume sequence from host. Host just stops sending SOFs without any "reason". This pattern only appears on HS port.

Deep sleep

• Connected device shall be disconnected upon entering deep sleep and connected back after exiting deep sleep
• RAM is unpowered during deep sleep and any information about the connected device (cached descriptors, device state.. ) is lost during deep sleep
• Currently, HNP cap is enabled before entering deep sleep in sleep_usb.c to prevent current leakage.

Testing

• usb_sleep_modes target tests
  • light sleep verification
  • deep sleep verification

TODO

• test the feature on all targets (also H4)

Limitations

• Light sleep: a device must be present in order to call root port suspend in a light sleep callback
  • Known "issue" from the original suspend/resume implementation before HCLK clock gating was introduced
  • Will be fixed in a separate PR

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Checklist

Before submitting a Pull Request, please ensure the following:

• 🚨 This PR does not introduce breaking changes.
• All CI checks (GH Actions) pass.
• Documentation is updated as needed.
• Tests are updated or added as necessary.
• Code is well-commented, especially in complex areas.
• Git history is clean — commits are squashed to the minimum necessary.