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Comment by linuxkerneldev | Hacker News Reader

> no, we don't use Android, unlike pretty much everyone else.

Most companies making EPD products use the base OS provided by their SoC vendor. Based on your spec which says 1GHz ARM A9 , I'm guessing you're using the NXP (formerly Freescale, now Qualcomm) i.mx6 SoloLite since that's the only 1GHz ARM A9 with an EPDC controller on the market. Freescale gives you a Linux EPD and an Android EPD Linux BSP, both of which use the same epdc driver with pretty much the same latency which is definitely pretty high, much higher than 55ms for sure.

> EPD is designed by e ink based on our requirements, e. g. the size and high DPI

Are you claiming that E Ink manufactured a custom 10.3" panel just for you?

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Again, I can't discuss too many technical details. But yes, it's an i.MX6SL, I thought we mentioned that on the web page.

And there are actually several drivers for the EPDC available. Two from freescale for the imx6 and imx7 (though there are some other improvements in the _v2, apart from imx7 support). There's also another one written by lab126, but I'm not sure if they actually use it. there's also some minor variations in the drivers in the different kernel branches and trees from NXP. And then you have the u-boot drivers. And I think there might be one in the bare metal SDK, but I haven't looked. And then you have the 5bit waveform support, which is a whole other story (with iffy GPL implications for some vendors I won't name).

And the display was designed based on our requirements, but we don't have any kind of exclusivity on it. there's already other devices coming out with it (you can find them if you google the specs, especially the awkward resolution we got thanks to the limits of the technology and our DPI requirement).

> it's an i.MX6SL, I thought we mentioned that on the web page.

Your website only says: "Processor 1 GHz ARM A9 CPU"

> Two from freescale for the imx6 and imx7

Ok, but you are using imx6.

> There's also another one written by lab126

Nope. That's the same driver from Freescale. You can download the kindle source to verify. https://www.amazon.com/gp/help/customer/display.html?nodeId=...

> then you have the u-boot drivers.

u-boot just draws a splash screen.

> you have the 5bit waveform support, which is a whole other story (with iffy GPL implications for some vendors I won't name).

I don't understand what you're trying to communicate. Why would a EPD waveform have any GPL implications? An EPD waveform is not software, it is a set of timing values and that's it.

> the display was designed based on our requirements

I'm having difficulty understanding what that means. It sounded like you were saying E Ink designed a panel for you, but maybe what you're saying is just that E Ink had a panel that met your requirements.

there are two epdc drivers in the kindle gpl releases. the source for the lab126 one is only available in the tarballs you linked (named mxc_epdc_fb_lab126.c).

as for the waveforms, I'm talking about support for the REAGL (sic) waveforms. grep for it in the linux source in the tarballs you linked to.

and e ink did not have a panel that met our requirements, and designed a new one after we talked with them.

edit; just to be clear, we don't use the lab126 driver, it was just an example of there being more drivers for the imx6 generation epdc.

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