Hello,
I have a display problem with a BeagleY-AI and two small 1024×600 HDMI touchscreens.
Problem
The image initially appears correctly. After approximately 2–5 seconds:
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The image starts fading toward black.
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Parts of previous images remain visible.
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The retained images appear stacked over the current image.
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Sometimes the display also shimmers or blinks rapidly.
This happens even when displaying a simple static test pattern directly through DRM/KMS. Therefore, it is not caused by my Qt/QML application.
Hardware
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Board: BeagleY-AI
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SoC: TI AM67A/J722S
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HDMI transmitter: ITE IT66122
Linux reports:IT66121 revision 0 -
Display resolution: 1024×600
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Touch controller: WaveShare WS170120, USB
0EEF:0005 -
Two separate small displays show the same problem.
Important comparison tests
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Small screen connected to a laptop:
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Image remains correct after more than 10 minutes.
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No fading or retained-image problem.
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BeagleY-AI connected to a large 1080p monitor:
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Image remains stable.
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The fading problem does not appear.
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Small screen connected to another board without the external ITE HDMI transmitter:
- Image remains stable.
Software tested
Original system: Kernel: 6.1.83-ti-arm64-r72. I also tested another installed kernel: 6.1.83-ti-arm64-r74.
I then built a separate diagnostic kernel: This kernel includes the newer upstream-style TI DSS DPI clock-edge configuration using ti,dpi-io-ctrl.
Live register verification showed:
DPI0_CLK_CTRL = 0x00000100.
But the problem still occurred.
I also tested:
Different HDMI/DVI transmitter configurations
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A higher ITE analog-front-end/output-strength configuration
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Different DPI sampling-edge configurations
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Native and non-native display modes
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Static color test patterns
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Different SD-card images and kernels
None of these tests removed the fading.