Re: [PATCH net-next] net: phy: Handle PHY reset during initial PHY ID read

[Andrew Lunn <andrew@lunn.ch>]

On Mon, Mar 02, 2026 at 10:44:57PM +0800, Chen-Yu Tsai wrote:
> The mdio device core handles reset GPIOs and controls for PHYs and
> MDIOs after the MDIO or PHY device is created. However this does not
> cover the initial PHY ID read _before_ the PHY device is created, since
> the PHY ID is needed for the PHY device. This causes PHY devices that
> have reset GPIOs or controls to not work after a reboot if the GPIO
> is left in the reset state; neither will it work if the reset GPIO is
> by default (for example, missing a pull-up) in the reset state.
> 
> One possible workaround is to place the reset GPIO or control property
> under the MDIO bus instead of under the PHY. However the common PHY
> device tree bindings already allow a reset for the PHY, so we should
> make some effort to support this.

Please either:

1) Add the ID to the DT

2) Work on driver/base, and add generic power on sequencing code which
can handle reset GPIOs, reset controllers, regulators, clocks etc. A
solution which works for PCIe, USB, SATA, and other enumerable
devices.  And then modify phylib to use this generic code.

    Andrew

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