AM69 DSI reference overlay

Hello!

I’m trying to create an AM69 device tree overlay for a DSI panel using the LVDS overlay ( aquila-am69_dsi-to-lvds_panel-cap-touch-10inch-lvds_overlay.dts) as a reference. However, using the LVDS overlay results in the following errors:

root@aquila-am69-12593326:~# dmesg | grep sn65
[    9.390854] sn65dsi83 3-002c: supply vcc not found, using dummy regulator
[    9.391228] sn65dsi83 3-002c: failed to attach dsi to host: -524
[    9.391233] sn65dsi83 3-002c: error -ENOTSUPP: failed to attach DSI host
[    9.391387] sn65dsi83: probe of 3-002c failed with error -524

Digging down, this error is due to the sn65dsi83 driver using DSI burst mode, which the bridge does not support. It seems there was an attempt to fix this, but for my case this doesn’t matter since the panel I need to implement doesn’t use an LVDS bridge.

Is there a different overlay I could use as a reference instead, one that has been verified to work with the AM69?

Thanks!

tdx-info in case it is relevant:

root@aquila-am69-12593326:~# tdx-info

Software summary
------------------------------------------------------------
Bootloader:               U-Boot
Kernel version:           6.6.58-7.1.0-gf874412b7190 #1 SMP PREEMPT Fri Dec  6 14:07:48 UTC 2024
Kernel command line:      root=PARTUUID=d435c6bc-02 ro rootwait console=tty1 console=ttyS2,115200
Distro name:              NAME="TDX Wayland with XWayland"
Distro version:           VERSION_ID=7.1.0-build.3
Distro variant:           -
Hostname:                 aquila-am69-12593326
------------------------------------------------------------

Hardware info
------------------------------------------------------------
HW model:                 Toradex Aquila AM69 on Aquila Development Board
Toradex version:          0088 V1.0A
Serial number:            12593326
Processor arch:           aarch64
------------------------------------------------------------

Hi, I’m the Toradex AI Assistant. The Toradex Support team will follow up with you shortly!

Did you like my answer?

:+1: :-1:


Hello!

Thank you for reaching out with your question. The errors you’re encountering suggest that the sn65dsi83 driver is attempting to use DSI burst mode, which is not supported by your current setup. This is likely why the LVDS overlay isn’t suitable for your DSI panel.

To resolve this, consider the following steps:

  1. Explore Existing Overlays: Check the Toradex Device Tree Overlays repository for overlays specifically designed for DSI panels without an LVDS bridge. These might serve as a better starting point for your configuration.

  2. Review Documentation: Ensure your DSI panel is compatible with the AM69 module by reviewing the relevant documentation. This can provide insights into any specific configurations or limitations.

  3. Modify or Create an Overlay: If no suitable overlay exists, you may need to modify an existing one or create a new overlay. Focus on configuring the DSI interface to avoid unsupported modes like burst mode.

  4. Consult Technical Resources: Review the datasheet for your DSI panel and any available driver documentation to understand the necessary settings and modes. This information will be crucial for correctly configuring the device tree.

By following these steps, you should be able to create a device tree overlay that works with your DSI panel on the AM69 module. If you encounter further issues, carefully review the error messages and configurations to identify any additional adjustments needed.

Best regards,
Toradex AI Assistant.

Please, also check if these links can help you solve your problem:

https://community.toradex.com/latest

Jitter when using DSI-> LVDS Adapter - #15 by alexkl.

Hi @matsjoyce-refeyn!

Welcome to Toradex Community! :partying_face:
Feel free to browse around :slight_smile:

You can indeed start from an existing device tree overlay to get some reference, but…

… the SN65DSI83 is a MIPI-DSI to LVDS converter. If you have a native MIPI-DSI display, this bridge/driver won’t help you.

As of now, there are some issues on Aquila AM69’s DSI interface.

So, for now, at least during development, it is recommended to use a Display Port display/monitor.

Best regards,

Thanks for the reply! I have tried doing a pure DSI overlay, but run into MISSING_HSYNC issues (likely what you are fixing), so I went back to try and start from a known good position.

Do you know roughly when DSI will be working, or if there is some notification I can subscribe to? So that I know when to restart testing on my end.

Hi @matsjoyce-refeyn !

That’s a fair question. Unfortunately, I can’t share a timeline right now.

I will update you via this thread when there is more information available. So, if you want, you can increase the “notification level” here:

Best regards,

Hi @matsjoyce-refeyn !

I was informed that DSI on Aquila AM69 is being worked on with high priority.

And, for now, we can’t share a timeline.

Best regards,

You can take a look at this overlay source. It’s for the Verdin AM62 module but can be used as a starting point.

https://git.toradex.com/cgit/device-tree-overlays.git/tree/overlays/verdin-am62_panel-cap-touch-10inch-dsi_overlay.dts?h=toradex_ti-linux-6.6.y

@henrique.tx Thank you for the update!