Re: [net-next v1] net: stmmac: starfive: Add serdes PHY init/deinit function

[Paolo Abeni]

On 4/10/25 9:04 AM, Minda Chen wrote:
> To support SGMII interface, add internal serdes PHY powerup/
> powerdown function.
> 
> Signed-off-by: Minda Chen <minda.chen@xxxxxxxxxxxxxxxx>
> ---
>  .../ethernet/stmicro/stmmac/dwmac-starfive.c  | 33 +++++++++++++++++++
>  1 file changed, 33 insertions(+)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c
> index 2013d7477eb7..f5923f847100 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c
> @@ -9,6 +9,8 @@
>  
>  #include <linux/mod_devicetable.h>
>  #include <linux/platform_device.h>
> +#include <linux/phy.h>
> +#include <linux/phy/phy.h>
>  #include <linux/property.h>
>  #include <linux/mfd/syscon.h>
>  #include <linux/regmap.h>
> @@ -28,6 +30,7 @@ struct starfive_dwmac_data {
>  struct starfive_dwmac {
>  	struct device *dev;
>  	const struct starfive_dwmac_data *data;
> +	struct phy *serdes_phy;
>  };
>  
>  static int starfive_dwmac_set_mode(struct plat_stmmacenet_data *plat_dat)
> @@ -80,6 +83,26 @@ static int starfive_dwmac_set_mode(struct plat_stmmacenet_data *plat_dat)
>  	return 0;
>  }
>  
> +static int starfive_dwmac_serdes_powerup(struct net_device *ndev, void *priv)
> +{
> +	struct starfive_dwmac *dwmac = priv;
> +	int ret;
> +
> +	ret = phy_init(dwmac->serdes_phy);
> +	if (ret)
> +		return ret;

This is called also in case of PM suspend/resume. Do you need to keep
the init here, or should that moved at probe time only? Similar question
for phy_exit() below.

Thanks!

Paolo