Re: [RFC Patch net-next v2 12/15] net: dsa: microchip: ksz9477: separate phylink mode from switch register

[Vladimir Oltean <olteanv@gmail.com>]

On Mon, May 30, 2022 at 04:12:54PM +0530, Arun Ramadoss wrote:
> As per 'commit 3506b2f42dff ("net: dsa: microchip: call
> phy_remove_link_mode during probe")' phy_remove_link_mode is added in
> the switch_register function after dsa_switch_register. In order to have
> the common switch register function, moving this phy init after
> dsa_register_switch using the new ksz_dev_ops.dsa_init hook.
> 
> Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
> ---
>  drivers/net/dsa/microchip/ksz9477.c    | 49 ++++++++++++++------------
>  drivers/net/dsa/microchip/ksz_common.c |  5 ++-
>  drivers/net/dsa/microchip/ksz_common.h |  1 +
>  3 files changed, 31 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/net/dsa/microchip/ksz9477.c b/drivers/net/dsa/microchip/ksz9477.c
> index ecce99b77ef6..c87ce0e2afd8 100644
> --- a/drivers/net/dsa/microchip/ksz9477.c
> +++ b/drivers/net/dsa/microchip/ksz9477.c
> @@ -1349,6 +1349,30 @@ static void ksz9477_switch_exit(struct ksz_device *dev)
>  	ksz9477_reset_switch(dev);
>  }
>  
> +static int ksz9477_dsa_init(struct ksz_device *dev)
> +{
> +	struct phy_device *phydev;
> +	int i;
> +
> +	for (i = 0; i < dev->phy_port_cnt; ++i) {
> +		if (!dsa_is_user_port(dev->ds, i))
> +			continue;

I understand this is just code movement, but this is more efficient:

	struct dsa_switch *ds = dev->ds;
	struct dsa_port *dp;

	dsa_switch_for_each_user_port(dp, ds) {
		...
	}

> +
> +		phydev = dsa_to_port(dev->ds, i)->slave->phydev;
> +
> +		/* The MAC actually cannot run in 1000 half-duplex mode. */
> +		phy_remove_link_mode(phydev,
> +				     ETHTOOL_LINK_MODE_1000baseT_Half_BIT);
> +
> +		/* PHY does not support gigabit. */
> +		if (!(dev->features & GBIT_SUPPORT))
> +			phy_remove_link_mode(phydev,
> +					     ETHTOOL_LINK_MODE_1000baseT_Full_BIT);
> +	}

I wonder why the driver did not just remove these from the supported
mask in the phylink validation procedure in the first place?
Adding these link mode fixups to a dev_ops callback named "dsa_init"
does not sound quite right.

> +
> +	return 0;
> +}
> +
>  static const struct ksz_dev_ops ksz9477_dev_ops = {
>  	.setup = ksz9477_setup,
>  	.get_port_addr = ksz9477_get_port_addr,
> @@ -1377,35 +1401,14 @@ static const struct ksz_dev_ops ksz9477_dev_ops = {
>  	.change_mtu = ksz9477_change_mtu,
>  	.max_mtu = ksz9477_max_mtu,
>  	.shutdown = ksz9477_reset_switch,
> +	.dsa_init = ksz9477_dsa_init,
>  	.init = ksz9477_switch_init,
>  	.exit = ksz9477_switch_exit,
>  };
>  
>  int ksz9477_switch_register(struct ksz_device *dev)
>  {
> -	int ret, i;
> -	struct phy_device *phydev;
> -
> -	ret = ksz_switch_register(dev, &ksz9477_dev_ops);
> -	if (ret)
> -		return ret;
> -
> -	for (i = 0; i < dev->phy_port_cnt; ++i) {
> -		if (!dsa_is_user_port(dev->ds, i))
> -			continue;
> -
> -		phydev = dsa_to_port(dev->ds, i)->slave->phydev;
> -
> -		/* The MAC actually cannot run in 1000 half-duplex mode. */
> -		phy_remove_link_mode(phydev,
> -				     ETHTOOL_LINK_MODE_1000baseT_Half_BIT);
> -
> -		/* PHY does not support gigabit. */
> -		if (!(dev->features & GBIT_SUPPORT))
> -			phy_remove_link_mode(phydev,
> -					     ETHTOOL_LINK_MODE_1000baseT_Full_BIT);
> -	}
> -	return ret;
> +	return ksz_switch_register(dev, &ksz9477_dev_ops);
>  }
>  EXPORT_SYMBOL(ksz9477_switch_register);
>  
> diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
> index ace5cf0ad5a8..f40d64858d35 100644
> --- a/drivers/net/dsa/microchip/ksz_common.c
> +++ b/drivers/net/dsa/microchip/ksz_common.c
> @@ -1253,7 +1253,10 @@ int ksz_switch_register(struct ksz_device *dev,
>  	/* Start the MIB timer. */
>  	schedule_delayed_work(&dev->mib_read, 0);
>  
> -	return 0;
> +	if (dev->dev_ops->dsa_init)
> +		ret = dev->dev_ops->dsa_init(dev);
> +
> +	return ret;
>  }
>  EXPORT_SYMBOL(ksz_switch_register);
>  
> diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
> index 872d378ac45c..23962f47df46 100644
> --- a/drivers/net/dsa/microchip/ksz_common.h
> +++ b/drivers/net/dsa/microchip/ksz_common.h
> @@ -213,6 +213,7 @@ struct ksz_dev_ops {
>  	void (*freeze_mib)(struct ksz_device *dev, int port, bool freeze);
>  	void (*port_init_cnt)(struct ksz_device *dev, int port);
>  	int (*shutdown)(struct ksz_device *dev);
> +	int (*dsa_init)(struct ksz_device *dev);
>  	int (*init)(struct ksz_device *dev);
>  	void (*exit)(struct ksz_device *dev);
>  };
> -- 
> 2.36.1
>