BBB RevD (and Industrial) IT66122 issues

Koan · March 5, 2026, 8:01am

I definitely agree if you submit the code upstream.
My name is Marco Cavallini, my email m.cavallini AT koansoftware.com

Good luck!

tKL · March 5, 2026, 3:59pm

Hi @Konstantin ,

Would you be able to share with me your ite driver?

I was trying to implement the 01_ite.patch you shared by adjusting it, but without success so far.

Thanks in advance

Koan · March 5, 2026, 4:21pm

Hi @tkl the patch provided in a message above by @Konstantin applies perfectly with the latest meta-ti/meta-ti-bsp kernel here

Konstantin · March 6, 2026, 2:54pm

Yes I can, I will attach my ite-it66122.c to this post completely.
This one is directly from a vanilla 6.12.57 I tested this out with and with that one I did the first test runs.
@Koan stands correct, my patches I posted earlier are pulled from my yocto layer which utilises the meta-ti kernel. But this file here is from vanilla 6.12.57 I created the yocto modification with.
This should … compile and run!

ite-it66121.c (62.9 KB)

tKL · March 9, 2026, 2:07pm

Thanks guys for your support! Appreciate it!

I was able to compile and adjust the driver. It works now without this annoying purple line on the left side of the screen, even the graphics still not 100%. I’m in contact with Seeed Technology Co., Ltd (manufacturer of this PCB), and they promised me to push beagle board to solve this in an appropriate way.

Thanks again!

RobertCNelson · March 13, 2026, 1:50pm

@tKL laughs, those emails to Seeed just go in a loop with the rest of us here! Can you share with everyone what LCD Pavel you are using… Please be a orderable link.

Found it, https://www.digikey.com/en/products/detail/matrix-orbital/HTT70A-TPC-BLM-B0-H5-CH-V5/7932528. I’ll add it my order test list

Regards,

tKL · March 15, 2026, 6:00am

@RobertCNelson

Exactly, that’s the link for the LCD panel I’m using.

RobertCNelson · March 15, 2026, 3:46pm

and ordered! fingers crossed i should get it monday..

Edit, no dice today, working from home tomorrow, fingers crossed i can grab it wednesday.

Regards,

Konstantin · April 7, 2026, 3:20pm

Well, now I am confused.
I am still trying to figure out how to find a minimal set of the codechange which helps our display, to prepare something sending to upstream.

But the initial code is from @Harshkumar so he needs to agree to this being put upstream or thinking about that, or am I confused now?

As said, I have a low time budget on doing this, but still I am trying to find out and prepare an upstream commit.

Regards, Konsti

Harshkumar · April 7, 2026, 3:57pm

Hi @RobertCNelson @Konstantin

I did fix purple line for YTS700tlbf-21-100c from Anders through my original fix.

I remember that someone from TI was refactoring ITE driver in Dec 2025 and which is mentioned in this thread.

@Konstantin and I had shared the working patch and driver files in this thread so at least my understanding is, TI and BBB.org engineering team work together and find the best minimal solution with their refactored driver by taking reference of our changes.
Also verify with shared LCD parts before upstream.

@Konstantin It would be great if you can share your LCD part as well.

Thanks

RobertCNelson · April 7, 2026, 4:02pm

A huge tilcdc refactor went into 7.0-rcX, right now display is ‘completely’ broken for IT66121 and IT66122

voodoo@BBB-ECO:~$ dmesg | grep -E "drm|it66121"
[    0.101101] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0
[    0.101231] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with /connector-hdmi
[    0.101896] /ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121
[    0.972886] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0
[    0.973013] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with /connector-hdmi
[    0.973580] /ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121
[    1.203726] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0
[    1.203851] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with /connector-hdmi
[    1.205797] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0
[    1.205904] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with /connector-hdmi
[    1.208259] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0
[    1.208377] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with /connector-hdmi
[    1.254697] /connector-hdmi: Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121
[    1.255064] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0
[    1.255161] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with /connector-hdmi
[    1.359171] /ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121
[    1.363879] /ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121
[    1.365248] /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0
[    1.365504] /ocp/interconnect@48000000/segment@300000/target-module@e000/lcdc@0:
Fixed dependency cycle(s) with
/ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121
[   23.494981] systemd[1]: Starting modprobe@drm.service - Load Kernel
Module drm...
[   26.634750] systemd[1]: modprobe@drm.service: Deactivated successfully.
[   26.718840] systemd[1]: Finished modprobe@drm.service - Load Kernel
Module drm.
[   47.935588] it66121 2-004d: supply vcn33 not found, using dummy regulator
[   48.060121] it66121 2-004d: supply vcn18 not found, using dummy regulator
[   48.067153] it66121 2-004d: supply vrf12 not found, using dummy regulator
[   48.290284] it66121 2-004d: IT66121 revision 1 probed
[   48.988756] [drm:drm_bridge_attach [drm]] *ERROR* failed to attach
bridge /ocp/interconnect@48000000/segment@100000/target-module@9c000/i2c@0/it66121
to encoder None-36: -22

So still stay with v6.18.x/v6.19.x (and earlier) with current hacks, till mainline (v7.0-rcX) has drm_bridge_attach working again..

Regards,