On 3/30/21 3:54 PM, Oleksij Rempel wrote:
> PHY loopback is needed for the ethernet controller self test support.
> This PHY was tested with the FEC sefltest.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> ---
>  drivers/net/phy/at803x.c | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
> index d7799beb811c..8679738cf2ab 100644
> --- a/drivers/net/phy/at803x.c
> +++ b/drivers/net/phy/at803x.c
> @@ -326,6 +326,30 @@ static int at803x_resume(struct phy_device *phydev)
>  	return phy_modify(phydev, MII_BMCR, BMCR_PDOWN | BMCR_ISOLATE, 0);
>  }
>  
> +static int at803x_loopback(struct phy_device *phydev, bool enable)
> +{
> +	int ret;
> +
> +	if (enable)
> +		ret = phy_clear_bits(phydev, MII_BMCR, BMCR_ANENABLE);
> +	else
> +		ret = phy_set_bits(phydev, MII_BMCR, BMCR_ANENABLE);
> +
> +	if (ret)
> +		return ret;
> +
> +	ret = genphy_loopback(phydev, enable);
> +
> +	/*
> +	 * Loop back needs some time to start transmitting packets in the loop.
> +	 * Documentation says nothing about it, so I take time which seems to
> +	 * work on AR8085.
> +	 */

/* Keep in mind the net multi line comment
 * style.
 */

Marc

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