Revert kernel patch causing USB 3 and PCIe breakage on ODROID-M1/M1S

[sairon]

Revert the patch changing phy reset behavior, requiring also changes in the device tree that are missing in the stable backport. The issue was reported to the regressions mailing list and hopefully future patch release should contain a proper fix.

The patch is added to the patches-rockchip directory, potentially affecting Green as well, although the broken peripherals are not used there.

Fixes #3837, fixes #3841

Summary by CodeRabbit

• Revert
  • Reverted a previous PHY reset patch for Rockchip naneng-combphy driver
  • Addresses regressions in USB3 and PCIe functionality on ODROID-M1 and ODROID-M1S devices

[coderabbitai]

📝 Walkthrough

Walkthrough

The pull request involves reverting a previous patch in the Rockchip naneng-combphy driver for Linux. The change modifies how the PHY reset control is obtained, switching from devm_reset_control_get(dev, "phy") to devm_reset_control_array_get_exclusive(dev). This reversion aims to address regressions in USB3 and PCIe functionality on ODROID-M1 and ODROID-M1S devices that occurred after a previous fix was applied.

Changes

File	Change Summary
buildroot-external/patches-rockchip/linux/0004-Revert-phy-rockchip-naneng-combphy-fix-phy-reset.patch	Reverts previous PHY reset control implementation
drivers/phy/rockchip/phy-rockchip-naneng-combphy.c	Modified PHY reset control method from devm_reset_control_get() to devm_reset_control_array_get_exclusive()

Assessment against linked issues

Objective	Addressed	Explanation
Resolve SATA M2 drive unavailability [#3837]	❓	Potential impact on storage functionality unclear
Fix USB 3 ports not working [#3841]	✅	Directly addresses USB3 functionality regression

The patch appears to primarily target the USB3 port functionality issue, with potential secondary benefits for overall device connectivity. The reversion of the previous PHY reset control implementation suggests an attempt to restore previous stable behavior for the ODROID-M1 and M1S devices.

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📜 Recent review details

Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between fbd5c2c and 8d42bef.

📒 Files selected for processing (1)

• buildroot-external/patches-rockchip/linux/0004-Revert-phy-rockchip-naneng-combphy-fix-phy-reset.patch (1 hunks)

🔇 Additional comments (3)

buildroot-external/patches-rockchip/linux/0004-Revert-phy-rockchip-naneng-combphy-fix-phy-reset.patch (3)

1-19: Well-structured commit message with clear rationale.

The commit message follows kernel patch guidelines and properly documents:

• The reason for the revert (USB3/PCIe regression)
• Affected devices (ODROID-M1/M1S)
• Link to regression report
• Clear indication this is temporary until upstream fix

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30-31: LGTM! Error handling remains robust.

The error handling is maintained with proper error checking and a descriptive error message.

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28-29: Verify device tree compatibility after reset control API change.

The change from devm_reset_control_get(dev, "phy") to devm_reset_control_array_get_exclusive(dev) reverts to using all available resets instead of a specific named reset. This restores compatibility with existing device trees that don't have the "phy" reset explicitly defined.

Run the following script to verify the device tree compatibility:

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