Re: [PATCH 3/9] ax88179_178a: Add support for AX88179A MMD access
From: Maxime Chevallier
Date: Wed Jul 01 2026 - 05:54:16 EST
Hi,
On 7/1/26 07:42, Birger Koblitz wrote:
> The AX88179A uses a much simpler Clause-45 MMD access interface,
> make use of this interface and abstract MMD read/write operations
> for the AX88179 and AX88179A architecture by introducing
> ax_read_mmd() and ax_write_mmd(), which in turn call the chips'
> respective implementation.
>
> Make use of the MMD read/write functions in the link-speed and EEE
> configuration settings via ethtool in order to support the
> AX179A-based chips. The AX88279 supports EEE only at 1000MBit speed,
> the other chips require full duplex.
Please split this into smaller patches, one for the mmd accessor conversion,
one for eee, one for the new chip support, etc.
>
> Signed-off-by: Birger Koblitz <mail@xxxxxxxxxxxxxxxxx>
[...]
> @@ -866,34 +924,63 @@ static int ax88179_set_link_ksettings(struct net_device *net,
> const struct ethtool_link_ksettings *cmd)
> {
> struct usbnet *dev = netdev_priv(net);
> + struct ax88179_data *data;
> + int v;
> +
> + data = dev->driver_priv;
> +
> + /* mii_ethtool_set_link_ksettings handles unknown bits in MII_ADVERTISE
> + * transparently, so for the 2.5GBit link speed of the AX_VERSION_AX88279
> + * we just set up ADVERTISE_RESV before calling mii_ethtool_set_link_ksettings
> + * at least for speeds < 2500
> + */
ADVERTISE_RESV isn't an unknown bit, it's been added in 802.3 as ADVERTISE_XNP
for Extended Next Page, see :
commit e7a62edd34b1 ("net: phy: qcom: at803x: Use the correct bit to disable extended next page")
we shoudln't use ADVERTISE_RESV anymore in-kernel (there are a few callsites left).
As this seems to be a vendor-specific behaviour for that bit, please add a
local #define for it in this driver, to make it clear that this is a device-specific
value.
Thanks,
Maxime