1 files changed, 86 insertions, 0 deletions

diff --git a/drivers/net/phy/adin.c b/drivers/net/phy/adin.c
index 5622a393e7cf..131b577a17e5 100644
--- a/drivers/net/phy/adin.c
+++ b/drivers/net/phy/adin.c
@@ -24,6 +24,17 @@
 #define   ADIN1300_AUTO_MDI_EN                  BIT(10)
 #define   ADIN1300_MAN_MDIX_EN                  BIT(9)
 
+#define ADIN1300_PHY_CTRL2                      0x0016
+#define   ADIN1300_DOWNSPEED_AN_100_EN          BIT(11)
+#define   ADIN1300_DOWNSPEED_AN_10_EN           BIT(10)
+#define   ADIN1300_GROUP_MDIO_EN                BIT(6)
+#define   ADIN1300_DOWNSPEEDS_EN        \
+        (ADIN1300_DOWNSPEED_AN_100_EN | ADIN1300_DOWNSPEED_AN_10_EN)
+
+#define ADIN1300_PHY_CTRL3                      0x0017
+#define   ADIN1300_LINKING_EN                   BIT(13)
+#define   ADIN1300_DOWNSPEED_RETRIES_MSK        GENMASK(12, 10)
+
 #define ADIN1300_INT_MASK_REG                   0x0018
 #define   ADIN1300_INT_MDIO_SYNC_EN             BIT(9)
 #define   ADIN1300_INT_ANEG_STAT_CHNG_EN        BIT(8)
@@ -243,6 +254,73 @@ static int adin_config_rmii_mode(struct phy_device *phydev)
                              ADIN1300_GE_RMII_CFG_REG, reg);
 }
 
+static int adin_get_downshift(struct phy_device *phydev, u8 *data)
+{
+        int val, cnt, enable;
+
+        val = phy_read(phydev, ADIN1300_PHY_CTRL2);
+        if (val < 0)
+                return val;
+
+        cnt = phy_read(phydev, ADIN1300_PHY_CTRL3);
+        if (cnt < 0)
+                return cnt;
+
+        enable = FIELD_GET(ADIN1300_DOWNSPEEDS_EN, val);
+        cnt = FIELD_GET(ADIN1300_DOWNSPEED_RETRIES_MSK, cnt);
+
+        *data = (enable && cnt) ? cnt : DOWNSHIFT_DEV_DISABLE;
+
+        return 0;
+}
+
+static int adin_set_downshift(struct phy_device *phydev, u8 cnt)
+{
+        u16 val;
+        int rc;
+
+        if (cnt == DOWNSHIFT_DEV_DISABLE)
+                return phy_clear_bits(phydev, ADIN1300_PHY_CTRL2,
+                                      ADIN1300_DOWNSPEEDS_EN);
+
+        if (cnt > 7)
+                return -E2BIG;
+
+        val = FIELD_PREP(ADIN1300_DOWNSPEED_RETRIES_MSK, cnt);
+        val |= ADIN1300_LINKING_EN;
+
+        rc = phy_modify(phydev, ADIN1300_PHY_CTRL3,
+                        ADIN1300_LINKING_EN | ADIN1300_DOWNSPEED_RETRIES_MSK,
+                        val);
+        if (rc < 0)
+                return rc;
+
+        return phy_set_bits(phydev, ADIN1300_PHY_CTRL2,
+                            ADIN1300_DOWNSPEEDS_EN);
+}
+
+static int adin_get_tunable(struct phy_device *phydev,
+                            struct ethtool_tunable *tuna, void *data)
+{
+        switch (tuna->id) {
+        case ETHTOOL_PHY_DOWNSHIFT:
+                return adin_get_downshift(phydev, data);
+        default:
+                return -EOPNOTSUPP;
+        }
+}
+
+static int adin_set_tunable(struct phy_device *phydev,
+                            struct ethtool_tunable *tuna, const void *data)
+{
+        switch (tuna->id) {
+        case ETHTOOL_PHY_DOWNSHIFT:
+                return adin_set_downshift(phydev, *(const u8 *)data);
+        default:
+                return -EOPNOTSUPP;
+        }
+}
+
 static int adin_config_init(struct phy_device *phydev)
 {
         int rc;
@@ -261,6 +339,10 @@ static int adin_config_init(struct phy_device *phydev)
         if (rc < 0)
                 return rc;
 
+        rc = adin_set_downshift(phydev, 4);
+        if (rc < 0)
+                return rc;
+
         phydev_dbg(phydev, "PHY is using mode '%s'\n",
                    phy_modes(phydev->interface));
 
@@ -474,6 +556,8 @@ static struct phy_driver adin_driver[] = {
                 .soft_reset     = adin_soft_reset,
                 .config_aneg    = adin_config_aneg,
                 .read_status    = adin_read_status,
+                .get_tunable    = adin_get_tunable,
+                .set_tunable    = adin_set_tunable,
                 .ack_interrupt  = adin_phy_ack_intr,
                 .config_intr    = adin_phy_config_intr,
                 .resume         = genphy_resume,
@@ -488,6 +572,8 @@ static struct phy_driver adin_driver[] = {
                 .soft_reset     = adin_soft_reset,
                 .config_aneg    = adin_config_aneg,
                 .read_status    = adin_read_status,
+                .get_tunable    = adin_get_tunable,
+                .set_tunable    = adin_set_tunable,
                 .ack_interrupt  = adin_phy_ack_intr,
                 .config_intr    = adin_phy_config_intr,
                 .resume         = genphy_resume,