On 6/27/22 3:34 PM, Jernej Škrabec wrote:

Dne nedelja, 26. junij 2022 ob 04:11:43 CEST je Samuel Holland napisal(a):

quoted

H6 requires I/O bias configuration on both of its PIO devices.
Previously it was only done for the main PIO.

The setting for Port L is at bit 0, so the bank calculation needs to
account for the pin base. Otherwise the wrong bit is used.

Fixes: cc62383fcebe ("pinctrl: sunxi: Support I/O bias voltage setting on
H6") Signed-off-by: Samuel Holland [off-list ref]

Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>

Did you noticed any improvement with this properly set? In theory, 3.3 V bias 
should always work, right?

I think it matters for inputs, which may not detect a high level state if the
bias (comparator reference) voltage is too high.

It looks like Orange Pi 3 has a 1.8 V supply for port M. I am not currently set
up to test the behavior with different bias settings, but I may do that if I get
the chance.

Regards,
Samuel