[PATCH net v2] net: phy: realtek: Clear MDIO_AN_10GBT_CTRL_ADV10G bit

[PATCH net v2] net: phy: realtek: Clear MDIO_AN_10GBT_CTRL_ADV10G bit

[Jan Klos]

On RTL8127A connected to a link partner that advertises 10000baseT
speed cannot be changed to anything other than 10000baseT as 10GbE
is always advertised regardless of any setting. Fix this by
clearing MDIO_AN_10GBT_CTRL_ADV10G bit in rtl822x_config_aneg()'s
call to phy_modify_mmd_changed().

Fixes: 83d962316128 ("net: phy: realtek: add RTL8127-internal PHY")
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Jan Klos <honza.klos@gmail.com>
---
v2: Patch formalities (rebase, tree name, tags, ccs)

 drivers/net/phy/realtek/realtek_main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/realtek/realtek_main.c b/drivers/net/phy/realtek/realtek_main.c
index 27268811f564..b65d0f5fa1a0 100644
--- a/drivers/net/phy/realtek/realtek_main.c
+++ b/drivers/net/phy/realtek/realtek_main.c
@@ -1802,7 +1802,8 @@ static int rtl822x_config_aneg(struct phy_device *phydev)
 		ret = phy_modify_mmd_changed(phydev, MDIO_MMD_VEND2,
 					     RTL_MDIO_AN_10GBT_CTRL,
 					     MDIO_AN_10GBT_CTRL_ADV2_5G |
-					     MDIO_AN_10GBT_CTRL_ADV5G, adv);
+					     MDIO_AN_10GBT_CTRL_ADV5G |
+					     MDIO_AN_10GBT_CTRL_ADV10G, adv);
 		if (ret < 0)
 			return ret;
 	}
-- 
2.54.0

AW: [PATCH net v2] net: phy: realtek: Clear MDIO_AN_10GBT_CTRL_ADV10G bit

[Markus Stockhausen]

> Von: Jan Klos <honza.klos@gmail.com> 
> Gesendet: Samstag, 20. Juni 2026 03:20
> Betreff: [PATCH net v2] net: phy: realtek: Clear MDIO_AN_10GBT_CTRL_ADV10G
bit
>
> On RTL8127A connected to a link partner that advertises 10000baseT
> speed cannot be changed to anything other than 10000baseT as 10GbE
> is always advertised regardless of any setting. Fix this by
> clearing MDIO_AN_10GBT_CTRL_ADV10G bit in rtl822x_config_aneg()'s
> call to phy_modify_mmd_changed().

As you are enhancing the mask, shouldn't this be "... by respecting ..."?

Markus

Re: [PATCH net v2] net: phy: realtek: Clear MDIO_AN_10GBT_CTRL_ADV10G bit

[Jan Klos]

On Sat, 20 Jun 2026 at 08:45, Markus Stockhausen
<markus.stockhausen@gmx.de> wrote:
>
> > Von: Jan Klos <honza.klos@gmail.com>
> > Gesendet: Samstag, 20. Juni 2026 03:20
> > Betreff: [PATCH net v2] net: phy: realtek: Clear MDIO_AN_10GBT_CTRL_ADV10G
> bit
> >
> > On RTL8127A connected to a link partner that advertises 10000baseT
> > speed cannot be changed to anything other than 10000baseT as 10GbE
> > is always advertised regardless of any setting. Fix this by
> > clearing MDIO_AN_10GBT_CTRL_ADV10G bit in rtl822x_config_aneg()'s
> > call to phy_modify_mmd_changed().
>
> As you are enhancing the mask, shouldn't this be "... by respecting ..."?
>
> Markus
>

I don't think so, in (__)phy_modify_mmd_changed() the mask is really used to
clear MMD register bits from old register value before setting new bits in set:
* @mask: bit mask of bits to clear
* @set: new value of bits set in mask to write to @regnum
*
* Unlocked helper function which allows a MMD register to be modified as
* new register value = (old register value & ~mask) | set