Re: [PATCH net-next v6 4/8] net: mdio: realtek-rtl9300: Configure hardware polling during probing

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] The `phy_poll` bitmap is declared and updated but never read, making it dead state-tracking code.
--

--- Patch [4]: [PATCH net-next v6 4/8] net: mdio: realtek-rtl9300: Configure hardware polling during probing ---
commit 36d18db7d9886e2eab892060b1cf7964f32514e4
Author: Markus Stockhausen <markus.stockhausen@gmx.de>

net: mdio: realtek-rtl9300: Configure hardware polling during probing

This commit toggles hardware polling for the Realtek Otto switches during
initialization and PHY attach/detach. This helps avoid conflicts with
probing and firmware loading sequences.

Link: https://lore.kernel.org/netdev/680696024a8648535ce6dee771fe4de67802e0e8.1769053496.git.daniel@makrotopia.org/

> diff --git a/drivers/net/mdio/mdio-realtek-rtl9300.c b/drivers/net/mdio/mdio-realtek-rtl9300.c
> index 3dee5bff41349..4b70aaeb8c3b3 100644
> --- a/drivers/net/mdio/mdio-realtek-rtl9300.c
> +++ b/drivers/net/mdio/mdio-realtek-rtl9300.c
[ ... ]
> @@ -200,6 +202,7 @@ struct otto_emdio_priv {
>  	const struct otto_emdio_info *info;
>  	struct regmap *regmap;
>  	struct mutex lock; /* protect HW access */
> +	DECLARE_BITMAP(phy_poll, MAX_PORTS);

[Severity: Low]
Is this phy_poll bitmap actually needed?

It looks like this field is updated when ports are attached and detached,
but it doesn't appear to be read anywhere in the driver. Could we remove it
entirely to simplify the state tracking?

[ ... ]
> @@ -582,6 +592,44 @@ static int otto_emdio_9310_setup_controller(struct otto_emdio_priv *priv)
>  	return 0;
>  }
>  
> +static int otto_emdio_notify_phy_attach(struct phy_device *phydev)
> +{
[ ... ]
> +	scoped_guard(mutex, &priv->lock) {
> +		ret = otto_emdio_set_port_polling(priv, port, true);
> +		if (!ret)
> +			__set_bit(port, priv->phy_poll);
> +	}

[Severity: Low]
If the bitmap is unread, can this __set_bit() update be dropped?

[ ... ]
> +static void otto_emdio_notify_phy_detach(struct phy_device *phydev)
> +{
[ ... ]
> +	scoped_guard(mutex, &priv->lock) {
> +		ret = otto_emdio_set_port_polling(priv, port, false);
> +		if (!ret)
> +			__clear_bit(port, priv->phy_poll);
> +	}

[Severity: Low]
Similarly, this __clear_bit() update could also be removed if the bitmap
is dead state-tracking code.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260724055611.1008577-1-markus.stockhausen@gmx.de?part=4