Re: [PATCH] pinctrl: nomadik: Fix pull direction debug info

[Andrew Halaney <ajhalaney@gmail.com>]

On Thu, Aug 13, 2020 at 10:06:55AM +0200, Linus Walleij wrote:
> Patch applied. It's clearly better like this. A plain bug.
Thanks!

> Do you think we can fix it properly by reading both the
> DATS and DATC registers  to do the inverse of what
> __nmk_gpio_set_pull() does and give a proper readout
> of pull up/down?
Sadly I don't think this will work. Both the DATS and DATC registers
return the contents of the DAT register on a read, so we'd be back
to where we are without the patch I posted. To me it seems like this
pin controller just doesn't support any method to probe the hardware
for the current pull state. I had considered seeing if this state
was stored in software anywhere, but decided against it since there's
a good chance a bootloader setup some pin configurations as well,
and that would cause the output to not match up with
the actual hardware state.

> Out of curiosity: what hardware are you testing this on?
I have access to an Accordo5 (sta1295 - not upstreamed).

Thanks,
Andrew