[PATCH/RFC 2/3] ethernet: add a PHY reset GPIO DT binding to sh_eth

Guennadi Liakhovetski g.liakhovetski at gmx.de
Mon Jul 8 06:49:47 EDT 2013


Hi Jason

Sorry for resuming an old thread, but I'd like to get this solved 
eventually.

On Fri, 25 Jan 2013, Jason Gunthorpe wrote:

> On Fri, Jan 25, 2013 at 11:34:55AM +0100, Guennadi Liakhovetski wrote:
> 
> > > Is there no need to reset the phy at runtime ?
> > 
> > No idea, I'm not developing the driver, I'm just porting one specific 
> > feature from one API to another with no functional changes (apart from 
> > postponing setting the GPIO).
> 
> Generally Linux relies on resetting the phy via the inband MDIO method,
> which is what Linux does. It is pretty much never required to reset
> via the hard pin - but you do need to generate a robust reset edge on
> the reset pin once after power up.

This all sounds good. So, is there a preferred way to do that? Where in 
the ethernet framework would you propose to hook up such a reset edge 
generation?

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/



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