On Friday, June 2, 2023 2:42:38 P.M. EDT Andrew Lunn wrote: > On Fri, Jun 02, 2023 at 02:26:58PM -0400, Detlev Casanova wrote: > > Ethern PHYs can have external an clock that needs to be activated before > > probing the PHY. > > `Ethernet PHYs can have an external clock.` > > We need to be careful with 'activated before probing the PHY'. phylib > itself will not activate the clock. You must be putting the IDs into > the compatible string, so the correct driver is loaded, and its probe > function is called. The probe itself enables the clock, so it is not > before probe, but during probe. > > I'm picky about this because we have issues with enumerating the MDIO > bus to find PHYs. Some boards needs the PHY taking out of reset, > regulators enabled, clocks enabled etc, before the PHY will respond on > the bus. It is hard for the core to do this, before the probe. So we > recommend putting IDs in the compatible, so the driver probe function > to do any additional setup needed. That makes sense, In my head, "probing" == calling phy_write/read() functions. But I get how this could be confused with the _probe() function. (And I just realised that there are typos) What about "Ethernet PHYs can have an external clock that needs to be activated before communicating with the PHY" ? > > Signed-off-by: Detlev Casanova <detlev.casanova@xxxxxxxxxxxxx> > > --- > > > > Documentation/devicetree/bindings/net/ethernet-phy.yaml | 6 ++++++ > > 1 file changed, 6 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml > > b/Documentation/devicetree/bindings/net/ethernet-phy.yaml index > > 4f574532ee13..c1241c8a3b77 100644 > > --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml > > +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml > > > > @@ -93,6 +93,12 @@ properties: > > the turn around line low at end of the control phase of the > > MDIO transaction. > > > > + clocks: > > + maxItems: 1 > > + description: > > + External clock connected to the PHY. If not specified it is assumed > > + that the PHY uses a fixed crystal or an internal oscillator. > > This text is good. Detlev
