Subject: Re: [PATCH net v4 1/2] phy: mscc: Use PHY_ID_MATCH_MODEL for VSC8584, VSC8582, VSC8575, VSC856X

From: "Russell King (Oracle)" <[email-masked]>
Date: Tue, 21 Oct 2025 10:09:00 +0100

On Fri, Oct 17, 2025 at 08:48:18AM +0200, Horatiu Vultur wrote:
> As the PHYs VSC8584, VSC8582, VSC8575 and VSC856X exists only as rev B,
> we can use PHY_ID_MATCH_MODEL to match exactly on revision B of the PHY.

I don't follow this. PHY_ID_MATCH_MODEL() uses a mask of bits 31:4,
omitting the revision field. So that is equivalent to a .phy_id_mask
of 0xfffffff0, which is what the code already uses.

> Because of this change then there is not need the check if it is a
> different revision than rev B in the function vsc8584_probe() as we
> already know that this will never happen.

Since bits 3:0 are masked out, this statement seems to be false.

> @@ -2587,9 +2576,8 @@ static struct phy_driver vsc85xx_driver[] = {
>  	.config_inband  = vsc85xx_config_inband,
>  },
>  {
> -	.phy_id		= PHY_ID_VSC856X,
> +	PHY_ID_MATCH_MODEL(PHY_ID_VSC856X),
>  	.name		= "Microsemi GE VSC856X SyncE",
> -	.phy_id_mask	= 0xfffffff0,
>  	/* PHY_GBIT_FEATURES */
>  	.soft_reset	= &genphy_soft_reset,
>  	.config_init    = &vsc8584_config_init,
> @@ -2667,9 +2655,8 @@ static struct phy_driver vsc85xx_driver[] = {
>  	.config_inband  = vsc85xx_config_inband,
>  },
>  {
> -	.phy_id		= PHY_ID_VSC8575,
> +	PHY_ID_MATCH_MODEL(PHY_ID_VSC8575),
>  	.name		= "Microsemi GE VSC8575 SyncE",
> -	.phy_id_mask	= 0xfffffff0,
>  	/* PHY_GBIT_FEATURES */
>  	.soft_reset	= &genphy_soft_reset,
>  	.config_init    = &vsc8584_config_init,
> @@ -2693,9 +2680,8 @@ static struct phy_driver vsc85xx_driver[] = {
>  	.config_inband  = vsc85xx_config_inband,
>  },
>  {
> -	.phy_id		= PHY_ID_VSC8582,
> +	PHY_ID_MATCH_MODEL(PHY_ID_VSC8582),
>  	.name		= "Microsemi GE VSC8582 SyncE",
> -	.phy_id_mask	= 0xfffffff0,
>  	/* PHY_GBIT_FEATURES */
>  	.soft_reset	= &genphy_soft_reset,
>  	.config_init    = &vsc8584_config_init,
> @@ -2719,9 +2705,8 @@ static struct phy_driver vsc85xx_driver[] = {
>  	.config_inband  = vsc85xx_config_inband,
>  },
>  {
> -	.phy_id		= PHY_ID_VSC8584,
> +	PHY_ID_MATCH_MODEL(PHY_ID_VSC8584),
>  	.name		= "Microsemi GE VSC8584 SyncE",
> -	.phy_id_mask	= 0xfffffff0,
>  	/* PHY_GBIT_FEATURES */
>  	.soft_reset	= &genphy_soft_reset,
>  	.config_init    = &vsc8584_config_init,

Due to what I've said above, the above part of the patch is a cleanup,
and functionally is a no-op.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!