Re: [PATCH] net: phy: dp83822: fix transmit amplitude if CONFIG_OF_MDIO not defined

[Gerhard Engleder <gerhard@engleder-embedded.com>]

On 12.03.25 18:23, Dimitri Fedrau via B4 Relay wrote:
> From: Dimitri Fedrau <dimitri.fedrau@liebherr.com>
> 
> When CONFIG_OF_MDIO is not defined the index for selecting the transmit
> amplitude voltage for 100BASE-TX is set to 0, but it should be -1, if there
> is no need to modify the transmit amplitude voltage. Add a flag to make
> sure there is a need to modify it.
> 
> Fixes: 4f3735e82d8a ("net: phy: dp83822: Add support for changing the transmit amplitude voltage")
> Signed-off-by: Dimitri Fedrau <dimitri.fedrau@liebherr.com>
> ---
>   drivers/net/phy/dp83822.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/phy/dp83822.c b/drivers/net/phy/dp83822.c
> index 3662f3905d5ade8ad933608fcaeabb714a588418..d69000cb0ceff28e8288ba24e0af1c960ea9cc97 100644
> --- a/drivers/net/phy/dp83822.c
> +++ b/drivers/net/phy/dp83822.c
> @@ -201,6 +201,7 @@ struct dp83822_private {
>   	bool set_gpio2_clk_out;
>   	u32 gpio2_clk_out;
>   	bool led_pin_enable[DP83822_MAX_LED_PINS];
> +	bool tx_amplitude_100base_tx_modify;
>   	int tx_amplitude_100base_tx_index;
>   };

You could instead init tx_amplitude_100base_tx_index in
dp8382x_probe() to -1.

But functional it should be ok.

Reviewed-by: Gerhard Engleder <gerhard@engleder-embedded.com>

Gerhard