[PATCH] net: stmmac: Support gpio high-level reset for devices requiring it

Andrew Lunn andrew at lunn.ch
Wed Jul 9 05:54:19 PDT 2025


On Wed, Jul 09, 2025 at 09:57:50AM +0800, lizhe wrote:
> Hi, Andrew
> 
> Thx,
> 
> 
> i conducted an experiment, and no matter whether i configured it as 
> 
> GPIO_ACTIVE_LOW or GPIO_ACTIVE_HIGH in the dts, the resulting
> 
> GPIO pin state was 0, indicating a low level.

You need to keep digging and understand why.

Scatter some printk() in the gpio core code. Does it recognise the
option in DT? Is GPIO_ACTIVE_LOW, FLAG_ACTIVE_LOW being set?

Put some prints into the actual GPIO driver, what is passed to it.

There is something interesting in gpio.txt:

Most controllers are specifying a generic flag bitfield in the last cell, so
for these, use the macros defined in
include/dt-bindings/gpio/gpio.h whenever possible:

It says 'Most'. Is the GPIO controller you are using not actually
doing this?

	Andrew



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