net: phy: Allow loopback speed selection for PHY drivers

PHY drivers support loopback mode, but it is not possible to select the
speed of the loopback mode. The speed is chosen by the set_loopback()
operation of the PHY driver. Same is valid for genphy_loopback().

There are PHYs that support loopback with different speeds. Extend
set_loopback() to make loopback speed selection possible.

Signed-off-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20250312203010.47429-2-gerhard@engleder-embedded.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

7 files changed, 39 insertions, 14 deletions

diff --git a/drivers/net/phy/adin1100.c b/drivers/net/phy/adin1100.c
index 6bb469429b9d..bd7a47a903ac 100644
--- a/drivers/net/phy/adin1100.c
+++ b/drivers/net/phy/adin1100.c
@@ -215,8 +215,11 @@ static int adin_resume(struct phy_device *phydev)
 	return adin_set_powerdown_mode(phydev, false);
 }
 
-static int adin_set_loopback(struct phy_device *phydev, bool enable)
+static int adin_set_loopback(struct phy_device *phydev, bool enable, int speed)
 {
+	if (enable && speed)
+		return -EOPNOTSUPP;
+
 	if (enable)
 		return phy_set_bits_mmd(phydev, MDIO_MMD_PCS, MDIO_PCS_10T1L_CTRL,
 					BMCR_LOOPBACK);
diff --git a/drivers/net/phy/dp83867.c b/drivers/net/phy/dp83867.c
index c1451df430ac..063266cafe9c 100644
--- a/drivers/net/phy/dp83867.c
+++ b/drivers/net/phy/dp83867.c
@@ -1009,8 +1009,11 @@ static void dp83867_link_change_notify(struct phy_device *phydev)
 	}
 }
 
-static int dp83867_loopback(struct phy_device *phydev, bool enable)
+static int dp83867_loopback(struct phy_device *phydev, bool enable, int speed)
 {
+	if (enable && speed)
+		return -EOPNOTSUPP;
+
 	return phy_modify(phydev, MII_BMCR, BMCR_LOOPBACK,
 			  enable ? BMCR_LOOPBACK : 0);
 }
diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
index dd254e36ca8a..f2ad675537d1 100644
--- a/drivers/net/phy/marvell.c
+++ b/drivers/net/phy/marvell.c
@@ -2131,13 +2131,19 @@ static void marvell_get_stats_simple(struct phy_device *phydev,
 		data[i] = marvell_get_stat_simple(phydev, i);
 }
 
-static int m88e1510_loopback(struct phy_device *phydev, bool enable)
+static int m88e1510_loopback(struct phy_device *phydev, bool enable, int speed)
 {
 	int err;
 
 	if (enable) {
 		u16 bmcr_ctl, mscr2_ctl = 0;
 
+		if (speed == SPEED_10 || speed == SPEED_100 ||
+		    speed == SPEED_1000)
+			phydev->speed = speed;
+		else if (speed)
+			return -EINVAL;
+
 		bmcr_ctl = mii_bmcr_encode_fixed(phydev->speed, phydev->duplex);
 
 		err = phy_write(phydev, MII_BMCR, bmcr_ctl);
diff --git a/drivers/net/phy/mxl-gpy.c b/drivers/net/phy/mxl-gpy.c
index 94d9cb727121..a6cca8d43253 100644
--- a/drivers/net/phy/mxl-gpy.c
+++ b/drivers/net/phy/mxl-gpy.c
@@ -813,7 +813,7 @@ static void gpy_get_wol(struct phy_device *phydev,
 	wol->wolopts = priv->wolopts;
 }
 
-static int gpy_loopback(struct phy_device *phydev, bool enable)
+static int gpy_loopback(struct phy_device *phydev, bool enable, int speed)
 {
 	struct gpy_priv *priv = phydev->priv;
 	u16 set = 0;
@@ -822,6 +822,9 @@ static int gpy_loopback(struct phy_device *phydev, bool enable)
 	if (enable) {
 		u64 now = get_jiffies_64();
 
+		if (speed)
+			return -EOPNOTSUPP;
+
 		/* wait until 3 seconds from last disable */
 		if (time_before64(now, priv->lb_dis_to))
 			msleep(jiffies64_to_msecs(priv->lb_dis_to - now));
@@ -845,15 +848,15 @@ static int gpy_loopback(struct phy_device *phydev, bool enable)
 	return 0;
 }
 
-static int gpy115_loopback(struct phy_device *phydev, bool enable)
+static int gpy115_loopback(struct phy_device *phydev, bool enable, int speed)
 {
 	struct gpy_priv *priv = phydev->priv;
 
 	if (enable)
-		return gpy_loopback(phydev, enable);
+		return gpy_loopback(phydev, enable, speed);
 
 	if (priv->fw_minor > 0x76)
-		return gpy_loopback(phydev, 0);
+		return gpy_loopback(phydev, 0, 0);
 
 	return genphy_soft_reset(phydev);
 }
diff --git a/drivers/net/phy/phy-c45.c b/drivers/net/phy/phy-c45.c
index 0bcbdce38107..8a0ffc3174ec 100644
--- a/drivers/net/phy/phy-c45.c
+++ b/drivers/net/phy/phy-c45.c
@@ -1228,8 +1228,11 @@ int gen10g_config_aneg(struct phy_device *phydev)
 }
 EXPORT_SYMBOL_GPL(gen10g_config_aneg);
 
-int genphy_c45_loopback(struct phy_device *phydev, bool enable)
+int genphy_c45_loopback(struct phy_device *phydev, bool enable, int speed)
 {
+	if (enable && speed)
+		return -EOPNOTSUPP;
+
 	return phy_modify_mmd(phydev, MDIO_MMD_PCS, MDIO_CTRL1,
 			      MDIO_PCS_CTRL1_LOOPBACK,
 			      enable ? MDIO_PCS_CTRL1_LOOPBACK : 0);
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 3f734e847e8e..09864c9635ac 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1838,9 +1838,9 @@ int phy_loopback(struct phy_device *phydev, bool enable)
 	}
 
 	if (phydev->drv->set_loopback)
-		ret = phydev->drv->set_loopback(phydev, enable);
+		ret = phydev->drv->set_loopback(phydev, enable, 0);
 	else
-		ret = genphy_loopback(phydev, enable);
+		ret = genphy_loopback(phydev, enable, 0);
 
 	if (ret)
 		goto out;
@@ -2610,12 +2610,18 @@ int genphy_resume(struct phy_device *phydev)
 }
 EXPORT_SYMBOL(genphy_resume);
 
-int genphy_loopback(struct phy_device *phydev, bool enable)
+int genphy_loopback(struct phy_device *phydev, bool enable, int speed)
 {
 	if (enable) {
 		u16 ctl = BMCR_LOOPBACK;
 		int ret, val;
 
+		if (speed == SPEED_10 || speed == SPEED_100 ||
+		    speed == SPEED_1000)
+			phydev->speed = speed;
+		else if (speed)
+			return -EINVAL;
+
 		ctl |= mii_bmcr_encode_fixed(phydev->speed, phydev->duplex);
 
 		phy_modify(phydev, MII_BMCR, ~0, ctl);
diff --git a/drivers/net/phy/xilinx_gmii2rgmii.c b/drivers/net/phy/xilinx_gmii2rgmii.c
index 7c51daecf18e..2024d8ef36d9 100644
--- a/drivers/net/phy/xilinx_gmii2rgmii.c
+++ b/drivers/net/phy/xilinx_gmii2rgmii.c
@@ -64,15 +64,16 @@ static int xgmiitorgmii_read_status(struct phy_device *phydev)
 	return 0;
 }
 
-static int xgmiitorgmii_set_loopback(struct phy_device *phydev, bool enable)
+static int xgmiitorgmii_set_loopback(struct phy_device *phydev, bool enable,
+				     int speed)
 {
 	struct gmii2rgmii *priv = mdiodev_get_drvdata(&phydev->mdio);
 	int err;
 
 	if (priv->phy_drv->set_loopback)
-		err = priv->phy_drv->set_loopback(phydev, enable);
+		err = priv->phy_drv->set_loopback(phydev, enable, speed);
 	else
-		err = genphy_loopback(phydev, enable);
+		err = genphy_loopback(phydev, enable, speed);
 	if (err < 0)
 		return err;