Re: [PATCH net v2] net: dsa: microchip: fix probe of I2C-connected KSZ8563

[Arun.Ramadoss]

On Fri, 2023-01-20 at 12:09 +0100, Ahmad Fatoum wrote:
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> Starting with commit eee16b147121 ("net: dsa: microchip: perform the
> compatibility check for dev probed"), the KSZ switch driver now bails
> out if it thinks the DT compatible doesn't match the actual chip ID
> read back from the hardware:
> 
>   ksz9477-switch 1-005f: Device tree specifies chip KSZ9893 but found
>   KSZ8563, please fix it!
> 
> For the KSZ8563, which used ksz_switch_chips[KSZ9893], this was fine
> at first, because it indeed shares the same chip id as the KSZ9893.
> 
> Commit b44908095612 ("net: dsa: microchip: add separate struct
> ksz_chip_data for KSZ8563 chip") started differentiating KSZ9893
> compatible chips by consulting the 0x1F register. The resulting
> breakage
> was fixed for the SPI driver in the same commit by introducing the
> appropriate ksz_switch_chips[KSZ8563], but not for the I2C driver.
> 
> Fix this for I2C-connected KSZ8563 now to get it probing again.
> 
> Fixes: b44908095612 ("net: dsa: microchip: add separate struct
> ksz_chip_data for KSZ8563 chip").
> Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
> Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>

Acked-by: Arun Ramadoss<arun.ramadoss@xxxxxxxxxxxxx>

> ---
> v1 -> v2:
>   - rewrote commit message and Fixes: to point at correct
>     culprit commit introducing regression (Arun)
>   - included Andrew's Reviewed-by
> ---
>  drivers/net/dsa/microchip/ksz9477_i2c.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/dsa/microchip/ksz9477_i2c.c
> b/drivers/net/dsa/microchip/ksz9477_i2c.c
> index c1a633ca1e6d..e315f669ec06 100644
> --- a/drivers/net/dsa/microchip/ksz9477_i2c.c
> +++ b/drivers/net/dsa/microchip/ksz9477_i2c.c
> @@ -104,7 +104,7 @@ static const struct of_device_id ksz9477_dt_ids[]
> = {
>         },
>         {
>                 .compatible = "microchip,ksz8563",
> -               .data = &ksz_switch_chips[KSZ9893]
> +               .data = &ksz_switch_chips[KSZ8563]
>         },
>         {
>                 .compatible = "microchip,ksz9567",
> --
> 2.30.2
>