Re: [PATCH net v1 1/1] net: dsa: microchip: make sure drive strength configuration is not lost by soft reset

[Arun.Ramadoss]

Hi Oleksij,

On Mon, 2024-03-04 at 14:56 +0100, Oleksij Rempel wrote:
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> 
> This driver has two separate reset sequence in different places:
> - gpio/HW reset on start of ksz_switch_register()
> - SW reset on start of ksz_setup()
> 
> The second one will overwrite drive strength configuration made in
> the
> ksz_switch_register().
> 
> To fix it, move ksz_parse_drive_strength() from ksz_switch_register()
> to
> ksz_setup().
> 
> Fixes: d67d7247f641 ("net: dsa: microchip: Add drive strength
> configuration")
> Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
> ---
>  drivers/net/dsa/microchip/ksz_common.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/dsa/microchip/ksz_common.c
> b/drivers/net/dsa/microchip/ksz_common.c
> index d58cc685478b1..83a5936506059 100644
> --- a/drivers/net/dsa/microchip/ksz_common.c
> +++ b/drivers/net/dsa/microchip/ksz_common.c
> @@ -2260,6 +2260,8 @@ static int ksz_pirq_setup(struct ksz_device
> *dev, u8 p)
>         return ksz_irq_common_setup(dev, pirq);
>  }
> 
> +static int ksz_parse_drive_strength(struct ksz_device *dev);
> +

IMO: move the ksz_parse_drive_strength( ) here instead of prototype
alone. Since the function is used in only one place and it will be
logical to follow. 

>  static int ksz_setup(struct dsa_switch *ds)
>  {
>         struct ksz_device *dev = ds->priv;
> @@ -2281,6 +2283,10 @@ static int ksz_setup(struct dsa_switch *ds)
>                 return ret;
>         }
> 
> +       ret = ksz_parse_drive_strength(dev);
> +       if (ret)
> +               return ret;
> +
>         /* set broadcast storm protection 10% rate */
>         regmap_update_bits(ksz_regmap_16(dev),
> regs[S_BROADCAST_CTRL],
>                            BROADCAST_STORM_RATE,
> @@ -4345,10 +4351,6 @@ int ksz_switch_register(struct ksz_device
> *dev)
>         for (port_num = 0; port_num < dev->info->port_cnt;
> ++port_num)
>                 dev->ports[port_num].interface =
> PHY_INTERFACE_MODE_NA;
>         if (dev->dev->of_node) {
> -               ret = ksz_parse_drive_strength(dev);
> -               if (ret)
> -                       return ret;
> -
>                 ret = of_get_phy_mode(dev->dev->of_node, &interface);
>                 if (ret == 0)
>                         dev->compat_interface = interface;
> --
> 2.39.2
>