diff mbox series

[v11,3/4] net: dsa: mv88e6xxx: Change serdes lane parameter type from u8 type to int

Message ID cc16a07f381973b0f4c987090bc307c8f854181d.1607488953.git.pavana.sharma@digi.com
State Superseded
Headers show
Series Add support for mv88e6393x family of Marvell | expand

Commit Message

Pavana Sharma Dec. 9, 2020, 5:05 a.m. UTC 
Returning 0 is no more an error case with MV88E6393 family
which has serdes lane numbers 0, 9 or 10.
So with this change .serdes_get_lane will return lane number
or -errno (-ENODEV or -EOPNOTSUPP).

Signed-off-by: Pavana Sharma <pavana.sharma@digi.com>
---
 drivers/net/dsa/mv88e6xxx/chip.c   | 28 ++++++------
 drivers/net/dsa/mv88e6xxx/chip.h   | 16 +++----
 drivers/net/dsa/mv88e6xxx/port.c   |  8 ++--
 drivers/net/dsa/mv88e6xxx/serdes.c | 72 +++++++++++++++---------------
 drivers/net/dsa/mv88e6xxx/serdes.h | 54 +++++++++++-----------
 5 files changed, 89 insertions(+), 89 deletions(-)

Comments

Andrew Lunn Dec. 9, 2020, 11:24 p.m. UTC | #1 
>On Wed, Dec 09, 2020 at 03:05:17PM +1000, Pavana Sharma wrote:
> Returning 0 is no more an error case with MV88E6393 family
> which has serdes lane numbers 0, 9 or 10.
> So with this change .serdes_get_lane will return lane number
> or -errno (-ENODEV or -EOPNOTSUPP).
> 
> Signed-off-by: Pavana Sharma <pavana.sharma@digi.com>

I see here you did actually act on my comment. Thanks.

But i also said:

> Other than that:
> 
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>

Please add such tags to new versions of the patches. It then makes it
easier for everybody to know the review state of the patches, which
have been reviewed and deemed O.K, and which need more review.

     Thanks
	Andrew
diff mbox series

Patch

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 34cca0a4b31c..367f69bd4c82 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -485,12 +485,12 @@  static int mv88e6xxx_serdes_pcs_get_state(struct dsa_switch *ds, int port,
 					  struct phylink_link_state *state)
 {
 	struct mv88e6xxx_chip *chip = ds->priv;
-	u8 lane;
+	int lane;
 	int err;
 
 	mv88e6xxx_reg_lock(chip);
 	lane = mv88e6xxx_serdes_get_lane(chip, port);
-	if (lane && chip->info->ops->serdes_pcs_get_state)
+	if (lane >= 0 && chip->info->ops->serdes_pcs_get_state)
 		err = chip->info->ops->serdes_pcs_get_state(chip, port, lane,
 							    state);
 	else
@@ -506,11 +506,11 @@  static int mv88e6xxx_serdes_pcs_config(struct mv88e6xxx_chip *chip, int port,
 				       const unsigned long *advertise)
 {
 	const struct mv88e6xxx_ops *ops = chip->info->ops;
-	u8 lane;
+	int lane;
 
 	if (ops->serdes_pcs_config) {
 		lane = mv88e6xxx_serdes_get_lane(chip, port);
-		if (lane)
+		if (lane >= 0)
 			return ops->serdes_pcs_config(chip, port, lane, mode,
 						      interface, advertise);
 	}
@@ -523,14 +523,14 @@  static void mv88e6xxx_serdes_pcs_an_restart(struct dsa_switch *ds, int port)
 	struct mv88e6xxx_chip *chip = ds->priv;
 	const struct mv88e6xxx_ops *ops;
 	int err = 0;
-	u8 lane;
+	int lane;
 
 	ops = chip->info->ops;
 
 	if (ops->serdes_pcs_an_restart) {
 		mv88e6xxx_reg_lock(chip);
 		lane = mv88e6xxx_serdes_get_lane(chip, port);
-		if (lane)
+		if (lane >= 0)
 			err = ops->serdes_pcs_an_restart(chip, port, lane);
 		mv88e6xxx_reg_unlock(chip);
 
@@ -544,11 +544,11 @@  static int mv88e6xxx_serdes_pcs_link_up(struct mv88e6xxx_chip *chip, int port,
 					int speed, int duplex)
 {
 	const struct mv88e6xxx_ops *ops = chip->info->ops;
-	u8 lane;
+	int lane;
 
 	if (!phylink_autoneg_inband(mode) && ops->serdes_pcs_link_up) {
 		lane = mv88e6xxx_serdes_get_lane(chip, port);
-		if (lane)
+		if (lane >= 0)
 			return ops->serdes_pcs_link_up(chip, port, lane,
 						       speed, duplex);
 	}
@@ -2424,11 +2424,11 @@  static irqreturn_t mv88e6xxx_serdes_irq_thread_fn(int irq, void *dev_id)
 	struct mv88e6xxx_chip *chip = mvp->chip;
 	irqreturn_t ret = IRQ_NONE;
 	int port = mvp->port;
-	u8 lane;
+	int lane;
 
 	mv88e6xxx_reg_lock(chip);
 	lane = mv88e6xxx_serdes_get_lane(chip, port);
-	if (lane)
+	if (lane >= 0)
 		ret = mv88e6xxx_serdes_irq_status(chip, port, lane);
 	mv88e6xxx_reg_unlock(chip);
 
@@ -2436,7 +2436,7 @@  static irqreturn_t mv88e6xxx_serdes_irq_thread_fn(int irq, void *dev_id)
 }
 
 static int mv88e6xxx_serdes_irq_request(struct mv88e6xxx_chip *chip, int port,
-					u8 lane)
+					int lane)
 {
 	struct mv88e6xxx_port *dev_id = &chip->ports[port];
 	unsigned int irq;
@@ -2465,7 +2465,7 @@  static int mv88e6xxx_serdes_irq_request(struct mv88e6xxx_chip *chip, int port,
 }
 
 static int mv88e6xxx_serdes_irq_free(struct mv88e6xxx_chip *chip, int port,
-				     u8 lane)
+				     int lane)
 {
 	struct mv88e6xxx_port *dev_id = &chip->ports[port];
 	unsigned int irq = dev_id->serdes_irq;
@@ -2490,11 +2490,11 @@  static int mv88e6xxx_serdes_irq_free(struct mv88e6xxx_chip *chip, int port,
 static int mv88e6xxx_serdes_power(struct mv88e6xxx_chip *chip, int port,
 				  bool on)
 {
-	u8 lane;
+	int lane;
 	int err;
 
 	lane = mv88e6xxx_serdes_get_lane(chip, port);
-	if (!lane)
+	if (lane < 0)
 		return 0;
 
 	if (on) {
diff --git a/drivers/net/dsa/mv88e6xxx/chip.h b/drivers/net/dsa/mv88e6xxx/chip.h
index 81c244fc0419..d81f586d67e8 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.h
+++ b/drivers/net/dsa/mv88e6xxx/chip.h
@@ -506,30 +506,30 @@  struct mv88e6xxx_ops {
 	int (*mgmt_rsvd2cpu)(struct mv88e6xxx_chip *chip);
 
 	/* Power on/off a SERDES interface */
-	int (*serdes_power)(struct mv88e6xxx_chip *chip, int port, u8 lane,
+	int (*serdes_power)(struct mv88e6xxx_chip *chip, int port, int lane,
 			    bool up);
 
 	/* SERDES lane mapping */
-	u8 (*serdes_get_lane)(struct mv88e6xxx_chip *chip, int port);
+	int (*serdes_get_lane)(struct mv88e6xxx_chip *chip, int port);
 
 	int (*serdes_pcs_get_state)(struct mv88e6xxx_chip *chip, int port,
-				    u8 lane, struct phylink_link_state *state);
+				    int lane, struct phylink_link_state *state);
 	int (*serdes_pcs_config)(struct mv88e6xxx_chip *chip, int port,
-				 u8 lane, unsigned int mode,
+				 int lane, unsigned int mode,
 				 phy_interface_t interface,
 				 const unsigned long *advertise);
 	int (*serdes_pcs_an_restart)(struct mv88e6xxx_chip *chip, int port,
-				     u8 lane);
+				     int lane);
 	int (*serdes_pcs_link_up)(struct mv88e6xxx_chip *chip, int port,
-				  u8 lane, int speed, int duplex);
+				  int lane, int speed, int duplex);
 
 	/* SERDES interrupt handling */
 	unsigned int (*serdes_irq_mapping)(struct mv88e6xxx_chip *chip,
 					   int port);
-	int (*serdes_irq_enable)(struct mv88e6xxx_chip *chip, int port, u8 lane,
+	int (*serdes_irq_enable)(struct mv88e6xxx_chip *chip, int port, int lane,
 				 bool enable);
 	irqreturn_t (*serdes_irq_status)(struct mv88e6xxx_chip *chip, int port,
-					 u8 lane);
+					 int lane);
 
 	/* Statistics from the SERDES interface */
 	int (*serdes_get_sset_count)(struct mv88e6xxx_chip *chip, int port);
diff --git a/drivers/net/dsa/mv88e6xxx/port.c b/drivers/net/dsa/mv88e6xxx/port.c
index 8128dc607cf4..8c4114d0eb4e 100644
--- a/drivers/net/dsa/mv88e6xxx/port.c
+++ b/drivers/net/dsa/mv88e6xxx/port.c
@@ -393,8 +393,8 @@  phy_interface_t mv88e6390x_port_max_speed_mode(int port)
 static int mv88e6xxx_port_set_cmode(struct mv88e6xxx_chip *chip, int port,
 				    phy_interface_t mode, bool force)
 {
-	u8 lane;
 	u16 cmode;
+	int lane;
 	u16 reg;
 	int err;
 
@@ -430,7 +430,7 @@  static int mv88e6xxx_port_set_cmode(struct mv88e6xxx_chip *chip, int port,
 		return 0;
 
 	lane = mv88e6xxx_serdes_get_lane(chip, port);
-	if (lane) {
+	if (lane >= 0) {
 		if (chip->ports[port].serdes_irq) {
 			err = mv88e6xxx_serdes_irq_disable(chip, port, lane);
 			if (err)
@@ -459,8 +459,8 @@  static int mv88e6xxx_port_set_cmode(struct mv88e6xxx_chip *chip, int port,
 		chip->ports[port].cmode = cmode;
 
 		lane = mv88e6xxx_serdes_get_lane(chip, port);
-		if (!lane)
-			return -ENODEV;
+		if (lane < 0)
+			return lane;
 
 		err = mv88e6xxx_serdes_power_up(chip, port, lane);
 		if (err)
diff --git a/drivers/net/dsa/mv88e6xxx/serdes.c b/drivers/net/dsa/mv88e6xxx/serdes.c
index 9c07b4f3d345..058cce01c01e 100644
--- a/drivers/net/dsa/mv88e6xxx/serdes.c
+++ b/drivers/net/dsa/mv88e6xxx/serdes.c
@@ -95,7 +95,7 @@  static int mv88e6xxx_serdes_pcs_get_state(struct mv88e6xxx_chip *chip,
 	return 0;
 }
 
-int mv88e6352_serdes_power(struct mv88e6xxx_chip *chip, int port, u8 lane,
+int mv88e6352_serdes_power(struct mv88e6xxx_chip *chip, int port, int lane,
 			   bool up)
 {
 	u16 val, new_val;
@@ -117,7 +117,7 @@  int mv88e6352_serdes_power(struct mv88e6xxx_chip *chip, int port, u8 lane,
 }
 
 int mv88e6352_serdes_pcs_config(struct mv88e6xxx_chip *chip, int port,
-				u8 lane, unsigned int mode,
+				int lane, unsigned int mode,
 				phy_interface_t interface,
 				const unsigned long *advertise)
 {
@@ -166,7 +166,7 @@  int mv88e6352_serdes_pcs_config(struct mv88e6xxx_chip *chip, int port,
 }
 
 int mv88e6352_serdes_pcs_get_state(struct mv88e6xxx_chip *chip, int port,
-				   u8 lane, struct phylink_link_state *state)
+				   int lane, struct phylink_link_state *state)
 {
 	u16 lpa, status;
 	int err;
@@ -187,7 +187,7 @@  int mv88e6352_serdes_pcs_get_state(struct mv88e6xxx_chip *chip, int port,
 }
 
 int mv88e6352_serdes_pcs_an_restart(struct mv88e6xxx_chip *chip, int port,
-				    u8 lane)
+				    int lane)
 {
 	u16 bmcr;
 	int err;
@@ -200,7 +200,7 @@  int mv88e6352_serdes_pcs_an_restart(struct mv88e6xxx_chip *chip, int port,
 }
 
 int mv88e6352_serdes_pcs_link_up(struct mv88e6xxx_chip *chip, int port,
-				 u8 lane, int speed, int duplex)
+				 int lane, int speed, int duplex)
 {
 	u16 val, bmcr;
 	int err;
@@ -230,10 +230,10 @@  int mv88e6352_serdes_pcs_link_up(struct mv88e6xxx_chip *chip, int port,
 	return mv88e6352_serdes_write(chip, MII_BMCR, bmcr);
 }
 
-u8 mv88e6352_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
+int mv88e6352_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
 {
 	u8 cmode = chip->ports[port].cmode;
-	u8 lane = 0;
+	int lane = -ENODEV;
 
 	if ((cmode == MV88E6XXX_PORT_STS_CMODE_100BASEX) ||
 	    (cmode == MV88E6XXX_PORT_STS_CMODE_1000BASEX) ||
@@ -245,7 +245,7 @@  u8 mv88e6352_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
 
 static bool mv88e6352_port_has_serdes(struct mv88e6xxx_chip *chip, int port)
 {
-	if (mv88e6xxx_serdes_get_lane(chip, port))
+	if (mv88e6xxx_serdes_get_lane(chip, port) >= 0)
 		return true;
 
 	return false;
@@ -354,7 +354,7 @@  static void mv88e6352_serdes_irq_link(struct mv88e6xxx_chip *chip, int port)
 }
 
 irqreturn_t mv88e6352_serdes_irq_status(struct mv88e6xxx_chip *chip, int port,
-					u8 lane)
+					int lane)
 {
 	irqreturn_t ret = IRQ_NONE;
 	u16 status;
@@ -372,7 +372,7 @@  irqreturn_t mv88e6352_serdes_irq_status(struct mv88e6xxx_chip *chip, int port,
 	return ret;
 }
 
-int mv88e6352_serdes_irq_enable(struct mv88e6xxx_chip *chip, int port, u8 lane,
+int mv88e6352_serdes_irq_enable(struct mv88e6xxx_chip *chip, int port, int lane,
 				bool enable)
 {
 	u16 val = 0;
@@ -411,10 +411,10 @@  void mv88e6352_serdes_get_regs(struct mv88e6xxx_chip *chip, int port, void *_p)
 	}
 }
 
-u8 mv88e6341_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
+int mv88e6341_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
 {
 	u8 cmode = chip->ports[port].cmode;
-	u8 lane = 0;
+	int lane = -ENODEV;
 
 	switch (port) {
 	case 5:
@@ -428,10 +428,10 @@  u8 mv88e6341_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
 	return lane;
 }
 
-u8 mv88e6390_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
+int mv88e6390_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
 {
 	u8 cmode = chip->ports[port].cmode;
-	u8 lane = 0;
+	int lane = -ENODEV;
 
 	switch (port) {
 	case 9:
@@ -451,12 +451,12 @@  u8 mv88e6390_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
 	return lane;
 }
 
-u8 mv88e6390x_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
+int mv88e6390x_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
 {
 	u8 cmode_port = chip->ports[port].cmode;
 	u8 cmode_port10 = chip->ports[10].cmode;
 	u8 cmode_port9 = chip->ports[9].cmode;
-	u8 lane = 0;
+	int lane = -ENODEV;
 
 	switch (port) {
 	case 2:
@@ -527,7 +527,7 @@  u8 mv88e6390x_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
 }
 
 /* Set power up/down for 10GBASE-R and 10GBASE-X4/X2 */
-static int mv88e6390_serdes_power_10g(struct mv88e6xxx_chip *chip, u8 lane,
+static int mv88e6390_serdes_power_10g(struct mv88e6xxx_chip *chip, int lane,
 				      bool up)
 {
 	u16 val, new_val;
@@ -554,7 +554,7 @@  static int mv88e6390_serdes_power_10g(struct mv88e6xxx_chip *chip, u8 lane,
 }
 
 /* Set power up/down for SGMII and 1000Base-X */
-static int mv88e6390_serdes_power_sgmii(struct mv88e6xxx_chip *chip, u8 lane,
+static int mv88e6390_serdes_power_sgmii(struct mv88e6xxx_chip *chip, int lane,
 					bool up)
 {
 	u16 val, new_val;
@@ -590,7 +590,7 @@  static struct mv88e6390_serdes_hw_stat mv88e6390_serdes_hw_stats[] = {
 
 int mv88e6390_serdes_get_sset_count(struct mv88e6xxx_chip *chip, int port)
 {
-	if (mv88e6390_serdes_get_lane(chip, port) == 0)
+	if (mv88e6390_serdes_get_lane(chip, port) < 0)
 		return 0;
 
 	return ARRAY_SIZE(mv88e6390_serdes_hw_stats);
@@ -602,7 +602,7 @@  int mv88e6390_serdes_get_strings(struct mv88e6xxx_chip *chip,
 	struct mv88e6390_serdes_hw_stat *stat;
 	int i;
 
-	if (mv88e6390_serdes_get_lane(chip, port) == 0)
+	if (mv88e6390_serdes_get_lane(chip, port) < 0)
 		return 0;
 
 	for (i = 0; i < ARRAY_SIZE(mv88e6390_serdes_hw_stats); i++) {
@@ -639,7 +639,7 @@  int mv88e6390_serdes_get_stats(struct mv88e6xxx_chip *chip, int port,
 	int i;
 
 	lane = mv88e6390_serdes_get_lane(chip, port);
-	if (lane == 0)
+	if (lane < 0)
 		return 0;
 
 	for (i = 0; i < ARRAY_SIZE(mv88e6390_serdes_hw_stats); i++) {
@@ -650,7 +650,7 @@  int mv88e6390_serdes_get_stats(struct mv88e6xxx_chip *chip, int port,
 	return ARRAY_SIZE(mv88e6390_serdes_hw_stats);
 }
 
-static int mv88e6390_serdes_enable_checker(struct mv88e6xxx_chip *chip, u8 lane)
+static int mv88e6390_serdes_enable_checker(struct mv88e6xxx_chip *chip, int lane)
 {
 	u16 reg;
 	int err;
@@ -665,7 +665,7 @@  static int mv88e6390_serdes_enable_checker(struct mv88e6xxx_chip *chip, u8 lane)
 				      MV88E6390_PG_CONTROL, reg);
 }
 
-int mv88e6390_serdes_power(struct mv88e6xxx_chip *chip, int port, u8 lane,
+int mv88e6390_serdes_power(struct mv88e6xxx_chip *chip, int port, int lane,
 			   bool up)
 {
 	u8 cmode = chip->ports[port].cmode;
@@ -690,7 +690,7 @@  int mv88e6390_serdes_power(struct mv88e6xxx_chip *chip, int port, u8 lane,
 }
 
 int mv88e6390_serdes_pcs_config(struct mv88e6xxx_chip *chip, int port,
-				u8 lane, unsigned int mode,
+				int lane, unsigned int mode,
 				phy_interface_t interface,
 				const unsigned long *advertise)
 {
@@ -749,7 +749,7 @@  int mv88e6390_serdes_pcs_config(struct mv88e6xxx_chip *chip, int port,
 }
 
 static int mv88e6390_serdes_pcs_get_state_sgmii(struct mv88e6xxx_chip *chip,
-	int port, u8 lane, struct phylink_link_state *state)
+	int port, int lane, struct phylink_link_state *state)
 {
 	u16 lpa, status;
 	int err;
@@ -772,7 +772,7 @@  static int mv88e6390_serdes_pcs_get_state_sgmii(struct mv88e6xxx_chip *chip,
 }
 
 static int mv88e6390_serdes_pcs_get_state_10g(struct mv88e6xxx_chip *chip,
-	int port, u8 lane, struct phylink_link_state *state)
+	int port, int lane, struct phylink_link_state *state)
 {
 	u16 status;
 	int err;
@@ -792,7 +792,7 @@  static int mv88e6390_serdes_pcs_get_state_10g(struct mv88e6xxx_chip *chip,
 }
 
 int mv88e6390_serdes_pcs_get_state(struct mv88e6xxx_chip *chip, int port,
-				   u8 lane, struct phylink_link_state *state)
+				   int lane, struct phylink_link_state *state)
 {
 	switch (state->interface) {
 	case PHY_INTERFACE_MODE_SGMII:
@@ -811,7 +811,7 @@  int mv88e6390_serdes_pcs_get_state(struct mv88e6xxx_chip *chip, int port,
 }
 
 int mv88e6390_serdes_pcs_an_restart(struct mv88e6xxx_chip *chip, int port,
-				    u8 lane)
+				    int lane)
 {
 	u16 bmcr;
 	int err;
@@ -827,7 +827,7 @@  int mv88e6390_serdes_pcs_an_restart(struct mv88e6xxx_chip *chip, int port,
 }
 
 int mv88e6390_serdes_pcs_link_up(struct mv88e6xxx_chip *chip, int port,
-				 u8 lane, int speed, int duplex)
+				 int lane, int speed, int duplex)
 {
 	u16 val, bmcr;
 	int err;
@@ -861,7 +861,7 @@  int mv88e6390_serdes_pcs_link_up(struct mv88e6xxx_chip *chip, int port,
 }
 
 static void mv88e6390_serdes_irq_link_sgmii(struct mv88e6xxx_chip *chip,
-					    int port, u8 lane)
+					    int port, int lane)
 {
 	u16 bmsr;
 	int err;
@@ -878,7 +878,7 @@  static void mv88e6390_serdes_irq_link_sgmii(struct mv88e6xxx_chip *chip,
 }
 
 static int mv88e6390_serdes_irq_enable_sgmii(struct mv88e6xxx_chip *chip,
-					     u8 lane, bool enable)
+					     int lane, bool enable)
 {
 	u16 val = 0;
 
@@ -890,7 +890,7 @@  static int mv88e6390_serdes_irq_enable_sgmii(struct mv88e6xxx_chip *chip,
 				      MV88E6390_SGMII_INT_ENABLE, val);
 }
 
-int mv88e6390_serdes_irq_enable(struct mv88e6xxx_chip *chip, int port, u8 lane,
+int mv88e6390_serdes_irq_enable(struct mv88e6xxx_chip *chip, int port, int lane,
 				bool enable)
 {
 	u8 cmode = chip->ports[port].cmode;
@@ -906,7 +906,7 @@  int mv88e6390_serdes_irq_enable(struct mv88e6xxx_chip *chip, int port, u8 lane,
 }
 
 static int mv88e6390_serdes_irq_status_sgmii(struct mv88e6xxx_chip *chip,
-					     u8 lane, u16 *status)
+					     int lane, u16 *status)
 {
 	int err;
 
@@ -917,7 +917,7 @@  static int mv88e6390_serdes_irq_status_sgmii(struct mv88e6xxx_chip *chip,
 }
 
 irqreturn_t mv88e6390_serdes_irq_status(struct mv88e6xxx_chip *chip, int port,
-					u8 lane)
+					int lane)
 {
 	u8 cmode = chip->ports[port].cmode;
 	irqreturn_t ret = IRQ_NONE;
@@ -976,7 +976,7 @@  static const u16 mv88e6390_serdes_regs[] = {
 
 int mv88e6390_serdes_get_regs_len(struct mv88e6xxx_chip *chip, int port)
 {
-	if (mv88e6xxx_serdes_get_lane(chip, port) == 0)
+	if (mv88e6xxx_serdes_get_lane(chip, port) < 0)
 		return 0;
 
 	return ARRAY_SIZE(mv88e6390_serdes_regs) * sizeof(u16);
@@ -990,7 +990,7 @@  void mv88e6390_serdes_get_regs(struct mv88e6xxx_chip *chip, int port, void *_p)
 	int i;
 
 	lane = mv88e6xxx_serdes_get_lane(chip, port);
-	if (lane == 0)
+	if (lane < 0)
 		return;
 
 	for (i = 0 ; i < ARRAY_SIZE(mv88e6390_serdes_regs); i++) {
diff --git a/drivers/net/dsa/mv88e6xxx/serdes.h b/drivers/net/dsa/mv88e6xxx/serdes.h
index 14315f26228a..ed3181e82da9 100644
--- a/drivers/net/dsa/mv88e6xxx/serdes.h
+++ b/drivers/net/dsa/mv88e6xxx/serdes.h
@@ -73,46 +73,46 @@ 
 #define MV88E6390_PG_CONTROL		0xf010
 #define MV88E6390_PG_CONTROL_ENABLE_PC		BIT(0)
 
-u8 mv88e6341_serdes_get_lane(struct mv88e6xxx_chip *chip, int port);
-u8 mv88e6352_serdes_get_lane(struct mv88e6xxx_chip *chip, int port);
-u8 mv88e6390_serdes_get_lane(struct mv88e6xxx_chip *chip, int port);
-u8 mv88e6390x_serdes_get_lane(struct mv88e6xxx_chip *chip, int port);
+int mv88e6341_serdes_get_lane(struct mv88e6xxx_chip *chip, int port);
+int mv88e6352_serdes_get_lane(struct mv88e6xxx_chip *chip, int port);
+int mv88e6390_serdes_get_lane(struct mv88e6xxx_chip *chip, int port);
+int mv88e6390x_serdes_get_lane(struct mv88e6xxx_chip *chip, int port);
 int mv88e6352_serdes_pcs_config(struct mv88e6xxx_chip *chip, int port,
-				u8 lane, unsigned int mode,
+				int lane, unsigned int mode,
 				phy_interface_t interface,
 				const unsigned long *advertise);
 int mv88e6390_serdes_pcs_config(struct mv88e6xxx_chip *chip, int port,
-				u8 lane, unsigned int mode,
+				int lane, unsigned int mode,
 				phy_interface_t interface,
 				const unsigned long *advertise);
 int mv88e6352_serdes_pcs_get_state(struct mv88e6xxx_chip *chip, int port,
-				   u8 lane, struct phylink_link_state *state);
+				   int lane, struct phylink_link_state *state);
 int mv88e6390_serdes_pcs_get_state(struct mv88e6xxx_chip *chip, int port,
-				   u8 lane, struct phylink_link_state *state);
+				   int lane, struct phylink_link_state *state);
 int mv88e6352_serdes_pcs_an_restart(struct mv88e6xxx_chip *chip, int port,
-				    u8 lane);
+				    int lane);
 int mv88e6390_serdes_pcs_an_restart(struct mv88e6xxx_chip *chip, int port,
-				    u8 lane);
+				    int lane);
 int mv88e6352_serdes_pcs_link_up(struct mv88e6xxx_chip *chip, int port,
-				 u8 lane, int speed, int duplex);
+				 int lane, int speed, int duplex);
 int mv88e6390_serdes_pcs_link_up(struct mv88e6xxx_chip *chip, int port,
-				 u8 lane, int speed, int duplex);
+				 int lane, int speed, int duplex);
 unsigned int mv88e6352_serdes_irq_mapping(struct mv88e6xxx_chip *chip,
 					  int port);
 unsigned int mv88e6390_serdes_irq_mapping(struct mv88e6xxx_chip *chip,
 					  int port);
-int mv88e6352_serdes_power(struct mv88e6xxx_chip *chip, int port, u8 lane,
+int mv88e6352_serdes_power(struct mv88e6xxx_chip *chip, int port, int lane,
 			   bool on);
-int mv88e6390_serdes_power(struct mv88e6xxx_chip *chip, int port, u8 lane,
+int mv88e6390_serdes_power(struct mv88e6xxx_chip *chip, int port, int lane,
 			   bool on);
-int mv88e6352_serdes_irq_enable(struct mv88e6xxx_chip *chip, int port, u8 lane,
+int mv88e6352_serdes_irq_enable(struct mv88e6xxx_chip *chip, int port, int lane,
 				bool enable);
-int mv88e6390_serdes_irq_enable(struct mv88e6xxx_chip *chip, int port, u8 lane,
+int mv88e6390_serdes_irq_enable(struct mv88e6xxx_chip *chip, int port, int lane,
 				bool enable);
 irqreturn_t mv88e6352_serdes_irq_status(struct mv88e6xxx_chip *chip, int port,
-					u8 lane);
+					int lane);
 irqreturn_t mv88e6390_serdes_irq_status(struct mv88e6xxx_chip *chip, int port,
-					u8 lane);
+					int lane);
 int mv88e6352_serdes_get_sset_count(struct mv88e6xxx_chip *chip, int port);
 int mv88e6352_serdes_get_strings(struct mv88e6xxx_chip *chip,
 				 int port, uint8_t *data);
@@ -129,18 +129,18 @@  void mv88e6352_serdes_get_regs(struct mv88e6xxx_chip *chip, int port, void *_p);
 int mv88e6390_serdes_get_regs_len(struct mv88e6xxx_chip *chip, int port);
 void mv88e6390_serdes_get_regs(struct mv88e6xxx_chip *chip, int port, void *_p);
 
-/* Return the (first) SERDES lane address a port is using, 0 otherwise. */
-static inline u8 mv88e6xxx_serdes_get_lane(struct mv88e6xxx_chip *chip,
-					   int port)
+/* Return the (first) SERDES lane address a port is using, -errno otherwise. */
+static inline int mv88e6xxx_serdes_get_lane(struct mv88e6xxx_chip *chip,
+						int port)
 {
 	if (!chip->info->ops->serdes_get_lane)
-		return 0;
+		return -EOPNOTSUPP;
 
 	return chip->info->ops->serdes_get_lane(chip, port);
 }
 
 static inline int mv88e6xxx_serdes_power_up(struct mv88e6xxx_chip *chip,
-					    int port, u8 lane)
+					    int port, int lane)
 {
 	if (!chip->info->ops->serdes_power)
 		return -EOPNOTSUPP;
@@ -149,7 +149,7 @@  static inline int mv88e6xxx_serdes_power_up(struct mv88e6xxx_chip *chip,
 }
 
 static inline int mv88e6xxx_serdes_power_down(struct mv88e6xxx_chip *chip,
-					      int port, u8 lane)
+					      int port, int lane)
 {
 	if (!chip->info->ops->serdes_power)
 		return -EOPNOTSUPP;
@@ -167,7 +167,7 @@  mv88e6xxx_serdes_irq_mapping(struct mv88e6xxx_chip *chip, int port)
 }
 
 static inline int mv88e6xxx_serdes_irq_enable(struct mv88e6xxx_chip *chip,
-					      int port, u8 lane)
+					      int port, int lane)
 {
 	if (!chip->info->ops->serdes_irq_enable)
 		return -EOPNOTSUPP;
@@ -176,7 +176,7 @@  static inline int mv88e6xxx_serdes_irq_enable(struct mv88e6xxx_chip *chip,
 }
 
 static inline int mv88e6xxx_serdes_irq_disable(struct mv88e6xxx_chip *chip,
-					       int port, u8 lane)
+					       int port, int lane)
 {
 	if (!chip->info->ops->serdes_irq_enable)
 		return -EOPNOTSUPP;
@@ -185,7 +185,7 @@  static inline int mv88e6xxx_serdes_irq_disable(struct mv88e6xxx_chip *chip,
 }
 
 static inline irqreturn_t
-mv88e6xxx_serdes_irq_status(struct mv88e6xxx_chip *chip, int port, u8 lane)
+mv88e6xxx_serdes_irq_status(struct mv88e6xxx_chip *chip, int port, int lane)
 {
 	if (!chip->info->ops->serdes_irq_status)
 		return IRQ_NONE;