net: thunderbolt: Allow reading link settings

In order to use Thunderbolt networking as part of bonding device it
needs to support ->get_link_ksettings() ethtool operation, so that the
bonding driver can read the link speed and the related attributes. Add
support for this to the driver.

Signed-off-by: Ian MacDonald <ian@netstatz.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://patch.msgid.link/20260115115646.328898-5-mika.westerberg@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/thunderbolt/main.c b/drivers/net/thunderbolt/main.c
index 57b226afeb844a2725a8a23bfa24439211e6b403..7aae5d915a1ebc1c6ef6f686df3514cab796c009 100644 (file)
--- a/drivers/net/thunderbolt/main.c
+++ b/drivers/net/thunderbolt/main.c
@@ -10,6 +10,7 @@
  */
 
 #include <linux/atomic.h>
+#include <linux/ethtool.h>
 #include <linux/highmem.h>
 #include <linux/if_vlan.h>
 #include <linux/jhash.h>
@@ -1265,6 +1266,53 @@ static const struct net_device_ops tbnet_netdev_ops = {
        .ndo_get_stats64 = tbnet_get_stats64,
 };
 
+static int tbnet_get_link_ksettings(struct net_device *dev,
+                                   struct ethtool_link_ksettings *cmd)
+{
+       const struct tbnet *net = netdev_priv(dev);
+       const struct tb_xdomain *xd = net->xd;
+       int speed;
+
+       ethtool_link_ksettings_zero_link_mode(cmd, supported);
+       ethtool_link_ksettings_zero_link_mode(cmd, advertising);
+
+       /* Figure out the current link speed and width */
+       switch (xd->link_speed) {
+       case 40:
+               speed = SPEED_80000;
+               break;
+
+       case 20:
+               if (xd->link_width == 2)
+                       speed = SPEED_40000;
+               else
+                       speed = SPEED_20000;
+               break;
+
+       case 10:
+               if (xd->link_width == 2) {
+                       speed = SPEED_20000;
+                       break;
+               }
+               fallthrough;
+
+       default:
+               speed = SPEED_10000;
+               break;
+       }
+
+       cmd->base.speed = speed;
+       cmd->base.duplex = DUPLEX_FULL;
+       cmd->base.autoneg = AUTONEG_DISABLE;
+       cmd->base.port = PORT_OTHER;
+
+       return 0;
+}
+
+static const struct ethtool_ops tbnet_ethtool_ops = {
+       .get_link_ksettings = tbnet_get_link_ksettings,
+};
+
 static void tbnet_generate_mac(struct net_device *dev)
 {
        const struct tbnet *net = netdev_priv(dev);
@@ -1315,6 +1363,7 @@ static int tbnet_probe(struct tb_service *svc, const struct tb_service_id *id)
 
        strcpy(dev->name, "thunderbolt%d");
        dev->netdev_ops = &tbnet_netdev_ops;
+       dev->ethtool_ops = &tbnet_ethtool_ops;
 
        /* ThunderboltIP takes advantage of TSO packets but instead of
         * segmenting them we just split the packet into Thunderbolt