Re: [PATCH] net: phy: turn carrier off on phy attach

From: David Miller
Date: Mon Jan 11 2016 - 17:17:30 EST


From: Sjoerd Simons <sjoerd.simons@xxxxxxxxxxxxxxx>
Date: Sat, 9 Jan 2016 19:44:05 +0100

> The operstate of a networking device initially IF_OPER_UNKNOWN aka
> "unknown", updated on carrier state changes (with carrier state being on
> by default). This means it will stay unknown unless the carrier state
> goes to off at some point, which is not the case if the phy is already
> up/connected at startup.
>
> Explicitly turn off the carrier on phy attach, leaving the phy state
> machine to turn the carrier on when it has done the initial negotiation.
>
> Signed-off-by: Sjoerd Simons <sjoerd.simons@xxxxxxxxxxxxxxx>

Florian or Andrew, please review this.

Thanks.

>
> ---
>
> drivers/net/phy/phy_device.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index 0bfbaba..a30ce1a 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -668,6 +668,11 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev,
>
> phydev->state = PHY_READY;
>
> + /* Signal to the core network layer the phy supports
> + * carrier detection
> + */
> + netif_carrier_off(phydev->attached_dev);
> +
> /* Do initial configuration here, now that
> * we have certain key parameters
> * (dev_flags and interface)
> --
> 2.7.0.rc3
>