Re: [PATCH] w5100: restore GPIO-based link detection

[Arthur Crépin Leblond]

On Tue, Aug 04, 2026 at 07:54:29PM +0200, Andrew Lunn wrote:
> On Tue, Aug 04, 2026 at 04:38:35PM +0200, Arthur Crépin Leblond wrote:
> > Commit dacf281771a9 ("w5100: remove unused gpio link detection")
> > dropped the link_gpio/link_irq handling on the grounds that no
> > devicetree user passed a "link" GPIO at the time.
> >
> > Signed-off-by: Arthur Crépin Leblond <arthur@xxxxxxxxxxxxx>
>
> Hi Arthur
>
> Do you understand the architecture of this device? What exactly is on
> the other end of this GPIO?
>
> https://wiznet.io/products/ethernet-chips/w5100
>
> suggests it has an integrated PHY. So why is a GPIO needed to report
> link?
>
> Thanks
> 	Andrew

Hi Andrew,

the W5100/W5500 exposes directly a LINKLED pin for the carrier status.
On my board (RPi), that pin is wired to a GPIO to detect changes on the host
directly via an interrupt.

Arthur