Subject: Re: [PATCH net-next] net: phy: marvell10g: add downshift tunable support

From: Andrew Lunn <[email-masked]>
Date: Fri, 17 Sep 2021 16:45:03 +0200

> +static int mv3310_set_downshift(struct phy_device *phydev, u8 ds)
> +{
> +	struct mv3310_priv *priv = dev_get_drvdata(&phydev->mdio.dev);
> +	u16 val;
> +	int err;
> +
> +	if (!priv->has_downshift)
> +		return -EOPNOTSUPP;
> +
> +	if (ds == DOWNSHIFT_DEV_DISABLE)
> +		return phy_clear_bits_mmd(phydev, MDIO_MMD_PCS, MV_PCS_DSC1,
> +					  MV_PCS_DSC1_ENABLE);
> +
> +	/* FIXME: The default is disabled, so should we disable? */
> +	if (ds == DOWNSHIFT_DEV_DEFAULT_COUNT)
> +		ds = 2;

Hi Russell

Rather than a FIXME, maybe just document that the hardware default is
disabled, which does not make too much sense, so default to 2 attempts?

      Andrew