Re: [PATCH net-next v3 00/10] macb usrio/tsu patches

Théo Lebrun
2026-03-12T10:09:55Z

Hello Conor,

On Tue Mar 10, 2026 at 6:17 PM CET, Conor Dooley wrote:
> At the very least, it'd be good of the soc vendor folks could check
> their platforms and see if their usrio stuff actually lines up with what
> the driver currently calls "macb_default_usrio". Ours didn't and it was
> a nasty surprise.
>
> Theo, you added eyeq5 recently. Does it genuinely have the same usrio
> bits as the at91 devices?

Sorry I missed your direct mention. After checking (because I completely
ignored this part of the code before), the User I/O feature is disabled
on EyeQ5 & EyeQ6H. It can be seen from DCFG1 BIT(9). It was invisible
because the USRIO register turns read-only when User I/O is disabled.

1. So I thought about adding runtime detection.

2. But then having eyeq5_config->usrio made no sense so I dropped it.

3. And then I thought that a config having usrio being NULL should
imply MACB_CAPS_USRIO_DISABLED to ensure we don't NULL dereference
the bp->usrio pointer.

#1 is useless for EyeQ combined with #2 and #3, but it should be useful
for the many compatibles that inherited the wrong default value of
at91_default_usrio.

I am sending those three patches as a reply, feel free to pick them up
if you consider them useful. They apply on top of your series and have
been tested on EyeQ5.

Thanks Conor,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering