Re: [PATCH v2 2/5] dt-bindings: display: Add the Ingenic X1600 LCD controller

[Olivier Louvignes]

Hi Nikolaus,

On Thu, Nov 05, 2026 at 11:27:12AM +0100, H. Nikolaus Schaller wrote:
> The manual for the x1600 is a bit ambiguous, but the x2000 and x2600
> documentation identifies this block as the "DPU (Display Processing Unit)
> Display Controller" (located at base address 0x13050000 on all three SoC).
[...]
> Please update the compatible string to "ingenic,x1600-dpu" (with "ingenic,dpu"
> as the fallback) and rename the file to ingenic-dpu.c to reflect that this is
> a scalable DPU driver not limited to "LCD".

Agreed on the name, v3 uses ingenic,x1600-dpu. The X1600 manual says
DPU too in its register and clock names, and when I checked the driver
against the X2000 manual it came out as the X2000's DPU without the
composer.

No ingenic,dpu fallback though: writing-bindings.rst asks for SoC
compatibles rather than family names, so an X2000 would be
ingenic,x2000-dpu, with the X1600's as its fallback if its registers
allow.

The driver keeps its file name for now. It only drives what the X1600
has and what I can test (parallel RGB from one plane), so the split
between the core and the interfaces, and the X2600's rotation, is better
shaped by whoever adds the X2000 with a board to test it on.

> However, this approach triggered a kernel lockup during boot
> right after successfully running lg35583_get_modes().

I can't reproduce it here, the R1 comes up with its panel at every boot
(with v3 again today). With nothing on the pins I don't know yet where
it would hang. If you get a log of it (the last lines with
initcall_debug) I'll have a look.

v3: https://lore.kernel.org/r/20261106112000.1612-1-olivier@xxxxxxxxx

Thanks for the review,
Olivier