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

From: Gerhard Engleder
Date: Wed Mar 12 2025 - 16:44:38 EST


On 12.03.25 18:23, Dimitri Fedrau via B4 Relay wrote:
From: Dimitri Fedrau <dimitri.fedrau@xxxxxxxxxxxx>

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@xxxxxxxxxxxx>
---
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@xxxxxxxxxxxxxxxxxxxxx>

Gerhard