Re: [PATCH net-next] net: phy: call phy_init_hw() in phy resume path

[Russell King (Oracle)]

On Fri, Apr 10, 2026 at 03:29:01PM +0100, Biju wrote:
> From: Ovidiu Panait <ovidiu.panait.rb@xxxxxxxxxxx>
> 
> When mac_managed_pm flag is set, mdio_bus_phy_resume() is skipped, so
> phy_init_hw(), which performs soft_reset and config_init, is not called
> during resume.
> 
> This is inconsistent with the non-mac_managed_pm path, where
> mdio_bus_phy_resume() calls phy_init_hw() before phy_resume() on every
> resume.
> 
> To align both paths, add a phy_init_hw() call at the top of
> __phy_resume(), before invoking the driver's resume callback. This
> guarantees the PHY undergoes soft reset and re-initialization regardless
> of whether PM is managed by the MAC or the MDIO bus.
> 
> Signed-off-by: Ovidiu Panait <ovidiu.panait.rb@xxxxxxxxxxx>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> ---
>  drivers/net/phy/phy_device.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index 0edff47478c2..8255f4208d66 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -2008,6 +2008,10 @@ int __phy_resume(struct phy_device *phydev)
>  	if (!phydrv || !phydrv->resume)
>  		return 0;
>  
> +	ret = phy_init_hw(phydev);
> +	if (ret)
> +		return ret;

Do we want to do this even when phydrv->resume is NULL?

Apart from that, looks fine to me - it seems some paths call
phy_init_hw() can be called with or without phydev->lock held, and
this one will call it with the lock held which seems to be okay.

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