HAOS 18.1 regression: Official Raspberry Pi Touch Display 2 touchscreen no longer works (Goodix probe fails with I2C error -5)

[BfnTurin]

Describe the issue you are experiencing

HAOS 18.1 regression: Official Raspberry Pi Touch Display 2 touchscreen no longer works (Goodix probe fails with I2C error -5)

Checklist

• I have searched for existing issues.
• This issue is reproducible.
• The issue did not occur on HAOS 18.0.

Environment

• Home Assistant OS: 18.1
• Previous working version: 18.0
• Board: Raspberry Pi 4 (64-bit)
• Display: Official Raspberry Pi Touch Display 2 (DSI)
• Installation type: Home Assistant OS
• Update method: OTA update via Settings → System → Updates

Description

After upgrading Home Assistant OS from 18.0 to 18.1, the touchscreen on the official Raspberry Pi Touch Display 2 stops working completely.

The display itself continues to function normally:

• The DSI display initializes correctly.
• Home Assistant boots normally.
• HAOS Kiosk launches successfully.
• Only the touchscreen input is lost.

Rolling back to HAOS 18.0 immediately restores touchscreen functionality without making any hardware or configuration changes.

Steps to reproduce

1. Start with HAOS 18.0 on a Raspberry Pi 4 using the official Raspberry Pi Touch Display 2.
2. Verify that the touchscreen works.
3. Update Home Assistant OS to 18.1 using Settings → System → Updates.
4. Reboot.

Expected behavior

The touchscreen should continue to function after upgrading.

Actual behavior

The display works normally, but touch input is completely unavailable.

No touchscreen input device is created.

Diagnostics

ha os info

board: rpi4-64
boot: B
boot_slots:
  A:
    state: inactive
    status: good
    version: "18.0"
  B:
    state: booted
    status: good
    version: "18.1"
data_disk: INTENSO-SSD-1642508005001923
update_available: false
version: "18.1"
version_latest: "18.1"

Input devices (/proc/bus/input/devices)

Only HDMI input devices are present:

I: Bus=001e Vendor=0000 Product=0000 Version=0001
N: Name="vc4-hdmi-0"

I: Bus=0000 Vendor=0000 Product=0000 Version=0000
N: Name="vc4-hdmi-0 HDMI Jack"

I: Bus=001e Vendor=0000 Product=0000 Version=0001
N: Name="vc4-hdmi-1"

I: Bus=0000 Vendor=0000 Product=0000 Version=0000
N: Name="vc4-hdmi-1 HDMI Jack"

No Goodix touchscreen input device is created.

Kernel log

Goodix-TS 10-005d: supply VDDIO not found, using dummy regulator
Goodix-TS 10-005d: Error reading 1 bytes from 0x8140: -5
Goodix-TS 10-005d: Error reading 1 bytes from 0x8140: -5
Goodix-TS 10-005d: I2C communication failure: -5
Goodix-TS 10-005d: probe with driver Goodix-TS failed with error -5

ili9881c-dsi fe700000.dsi.0: supply power not found, using dummy regulator
vc4-drm gpu: bound fe700000.dsi

The display initializes successfully, but the Goodix touchscreen probe fails with an I²C communication error (-5), preventing creation of the touchscreen input device.

Additional observations

• The issue is reproducible.
• Rolling back to HAOS 18.0 immediately restores touchscreen functionality.
• No hardware changes were made.
• This appears to be a regression introduced in HAOS 18.1 (or its kernel/device tree changes).

Please let me know if additional diagnostics or testing would be helpful.

What operating system image do you use?

rpi4-64 (Raspberry Pi 4/400 64-bit OS)

What version of Home Assistant Operating System is installed?

18.1

Did the problem occur after upgrading the Operating System?

Yes

Hardware details

Raspberry Pi 4 GB with official Raspberry Pi Touch Display 2.

Steps to reproduce the issue

1. Start with HAOS 18.0 on a Raspberry Pi 4 using the official Raspberry Pi Touch Display 2.
2. Verify that the touchscreen works.
3. Update Home Assistant OS to 18.1 using Settings → System → Updates.
4. Reboot.

Anything in the Supervisor logs that might be useful for us?

/

Anything in the Host logs that might be useful for us?

/

System information

No response

Additional information

No response

[agners]

I've proposed a fix for this to the Raspberry Pi kernel: raspberrypi/linux#7482

Root cause analysis: on the Touch Display 2 the Goodix touch controller's reset is sequenced by the display's microcontroller rather than by SoC GPIOs. In that configuration the goodix driver has no reset retry path, so if its initial I2C test runs before the controller is out of reset, the probe fails permanently with -EIO — which side wins this race depends on probe ordering and can shift between kernel builds (18.0 vs 18.1). The patch makes the driver defer probing in this case so it is retried once the display stack is up.

We are also considering carrying this patch in the next HAOS release. Note that the fix is untested on real hardware so far — if anyone affected is set up to build/test a patched kernel, feedback on the linked PR would be very welcome.