Re: [PATCH net-next 4/9] net: dsa: microchip: remove setup_rgmii_delay() KSZ operation

[Paolo Abeni <pabeni@redhat.com>]

On 5/26/26 11:47 AM, Bastien Curutchet (Schneider Electric) wrote:
> setup_rgmii_delay() operation is only used once during the common phylink
> MAC configuration. Only the lan937x switch implements this
> setup_rgmii_delay().
> 
> Remove the setup_rgmii_delay operation from ksz_dev_ops.
> Implement a lan937x-specific phylink MAC configuration that does this
> RGMII delay setup.
> Export ksz_set_xmii since it's needed by the lan937x implementation.
> 
> Signed-off-by: Bastien Curutchet (Schneider Electric) <bastien.curutchet@bootlin.com>
> ---
>  drivers/net/dsa/microchip/ksz_common.c   |  6 +-----
>  drivers/net/dsa/microchip/ksz_common.h   |  2 +-
>  drivers/net/dsa/microchip/lan937x_main.c | 29 +++++++++++++++++++++++++++--
>  3 files changed, 29 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
> index 5fb151fbf4f3..d6511fcebcf2 100644
> --- a/drivers/net/dsa/microchip/ksz_common.c
> +++ b/drivers/net/dsa/microchip/ksz_common.c
> @@ -3127,8 +3127,7 @@ int ksz_set_mac_eee(struct dsa_switch *ds, int port,
>  	return 0;
>  }
>  
> -static void ksz_set_xmii(struct ksz_device *dev, int port,
> -			 phy_interface_t interface)
> +void ksz_set_xmii(struct ksz_device *dev, int port, phy_interface_t interface)
>  {
>  	const u8 *bitval = dev->info->xmii_ctrl1;
>  	struct ksz_port *p = &dev->ports[port];
> @@ -3233,9 +3232,6 @@ void ksz_phylink_mac_config(struct phylink_config *config,
>  	}
>  
>  	ksz_set_xmii(dev, port, state->interface);
> -
> -	if (dev->dev_ops->setup_rgmii_delay)
> -		dev->dev_ops->setup_rgmii_delay(dev, port);
>  }
>  
>  bool ksz_get_gbit(struct ksz_device *dev, int port)
> diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
> index 804912fdd2db..ab08c98ed257 100644
> --- a/drivers/net/dsa/microchip/ksz_common.h
> +++ b/drivers/net/dsa/microchip/ksz_common.h
> @@ -410,7 +410,6 @@ struct ksz_dev_ops {
>  			   u8 data);
>  	void (*freeze_mib)(struct ksz_device *dev, int port, bool freeze);
>  	void (*port_init_cnt)(struct ksz_device *dev, int port);
> -	void (*setup_rgmii_delay)(struct ksz_device *dev, int port);
>  	int (*tc_cbs_set_cinc)(struct ksz_device *dev, int port, u32 val);
>  	int (*init)(struct ksz_device *dev);
>  };
> @@ -468,6 +467,7 @@ void ksz_phylink_get_caps(struct dsa_switch *ds, int port,
>  void ksz_phylink_mac_disable_tx_lpi(struct phylink_config *config);
>  int ksz_phylink_mac_enable_tx_lpi(struct phylink_config *config,
>  				  u32 timer, bool tx_clock_stop);
> +void ksz_set_xmii(struct ksz_device *dev, int port, phy_interface_t interface);
>  void ksz_phylink_mac_config(struct phylink_config *config,
>  			    unsigned int mode,
>  			    const struct phylink_link_state *state);
> diff --git a/drivers/net/dsa/microchip/lan937x_main.c b/drivers/net/dsa/microchip/lan937x_main.c
> index 57e289637193..f8f220242f7a 100644
> --- a/drivers/net/dsa/microchip/lan937x_main.c
> +++ b/drivers/net/dsa/microchip/lan937x_main.c
> @@ -643,6 +643,32 @@ static void lan937x_setup_rgmii_delay(struct ksz_device *dev, int port)
>  	}
>  }
>  
> +static void lan937x_phylink_mac_config(struct phylink_config *config,
> +				       unsigned int mode,
> +				       const struct phylink_link_state *state)
> +{
> +	struct dsa_port *dp = dsa_phylink_to_port(config);
> +	struct ksz_device *dev = dp->ds->priv;
> +	int port = dp->index;
> +
> +	/* Internal PHYs */
> +	if (dev->info->internal_phy[port])
> +		return;
> +
> +	/* No need to configure XMII control register when using SGMII. */
> +	if (ksz_is_sgmii_port(dev, port))
> +		return;
> +
> +	if (phylink_autoneg_inband(mode)) {
> +		dev_err(dev->dev, "In-band AN not supported!\n");
> +		return;
> +	}
> +
> +	ksz_set_xmii(dev, port, state->interface);
> +
> +	lan937x_setup_rgmii_delay(dev, port);

I think you can avoid some code duplication with something alike the
following:

- factor out of ksz_phylink_mac_config() a  __ksz_phylink_mac_config(),
helper, with the latter doing all the work and returning true when
actually calling ksz_set_xmii()

- implement lan937x_phylink_mac_config() on top of
__ksz_phylink_mac_config():

	if (__ksz_phylink_mac_config())
		lan937x_setup_rgmii_delay(dev, port);

/P