Portabylity E-Ink panel waveform for newer kernel with EPDC-support

[denis-shipovsky]

Hello,

We develop custom board based on VAR-SOM-MX7 module with imx7dsabresd processor and schematic reference V5 development kit from E-INK .

We use large 32"-42" e-inc displays EC312TT2, ED312TT2, ED420TE1T1 and have appropriate firmware files.

Currently we use Linux imx7dsabresd 3.14.52-1.1.1_ga+gdb1bcba, as it has all required patches and instructions to apply them. Patch provides also some precompiled library - "libfw.a". But as mentioned in sect.10.3.4.2 Using a Custom Waveform: "waveform file is loaded by the EPDC driver using the Linux firmware APIs". I don't know is "libfw.a" patched.

Tell me please about right way to switch to newer yocto version. E-ink says thay do not provide support for newer version. We have try to run latest yocto bsp from Varisite, but image is drawn incorrectly.

On this forum get information about waveform files. This files provide display producer. And there is some script, which convert them to firmware (*.fw) files. Are this files linux-kernel version dependent?

[Stepan]

Denis good afternoon! We now have a similar task to yours, and we have problems, could you contact me, maybe you have already encountered this problem. Please email me ignis.stepan@gmail.com

[denis-shipovsky]

Hello, Stepan!

We continue using old kernel 3.14.

It mostly satisfy us, except we need newer python3.8.

We have try to patch latest kernel 5.4, but fail. There was no any more time to play with it.

But if have any success, please inform.

[Stepan]

Thanks for the answer! And you didn't happen to figure out the disclosure or signal format that is sold to the display from the V5 board. We are making our own controller and have not been able to get the format V5 sends to the display.

[nxf63675]

Hi @denis-shipovsky,

As for your questions, these files are not depending on the version of the software, but not all the versions are compatible with the newer Linux versions, one can find a porting Linux guide on the documentation of each BSP distribution that is available on the next link:

https://www.nxp.com/design/software/embedded-software/i-mx-software/embedded-linux-for-i-mx-applicat...

Regards,

Israel.

[denis-shipovsky]

Hi,

Thanks for reply!

I have searched BSP distribution pages by "epdc" or "fw". There is no resultes.

Then I choose latest version with "i.MX 7Dual SABRESD​" support - "Linux 5.4.70_2.3.0​"

I have downloaded documentation for release and found i.MX_Porting_Guide.pdf. There is no search result for "epdc" too.

As you mention these files are not depending on the version of the software.

Is "Linux 5.4.70_2.3.0​" good starting point for testing EPDC driver with our displays?

[nxf63675 · Accepted solution]

Hi @denis-shipovsky,

As the Linux version that you selected is a good way to start and is stable, the main issue is that you are using a very old BSP, and the changes between these versions are so many, so first I would try older BSP's likes Linux 4.14.XX and then if you do not see problems update to a new one, if you insist to use a newer version you can look for the changes between versions at the Linux release notes.

Regards,

Israel.