net: dsa: mv88e6xxx: Save power by disabling SerDes trasmitter and receiver

Save power on 88E6393X by disabling SerDes receiver and transmitter
after SerDes is SerDes is disabled.

Signed-off-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org # de776d0d316f ("net: dsa: mv88e6xxx: add support for mv88e6393x family")
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/dsa/mv88e6xxx/serdes.c b/drivers/net/dsa/mv88e6xxx/serdes.c
index 3a62445..ceb63d7 100644 (file)
--- a/drivers/net/dsa/mv88e6xxx/serdes.c
+++ b/drivers/net/dsa/mv88e6xxx/serdes.c
@@ -1271,6 +1271,28 @@ void mv88e6390_serdes_get_regs(struct mv88e6xxx_chip *chip, int port, void *_p)
        }
 }
 
+static int mv88e6393x_serdes_power_lane(struct mv88e6xxx_chip *chip, int lane,
+                                       bool on)
+{
+       u16 reg;
+       int err;
+
+       err = mv88e6390_serdes_read(chip, lane, MDIO_MMD_PHYXS,
+                                   MV88E6393X_SERDES_CTRL1, &reg);
+       if (err)
+               return err;
+
+       if (on)
+               reg &= ~(MV88E6393X_SERDES_CTRL1_TX_PDOWN |
+                        MV88E6393X_SERDES_CTRL1_RX_PDOWN);
+       else
+               reg |= MV88E6393X_SERDES_CTRL1_TX_PDOWN |
+                      MV88E6393X_SERDES_CTRL1_RX_PDOWN;
+
+       return mv88e6390_serdes_write(chip, lane, MDIO_MMD_PHYXS,
+                                     MV88E6393X_SERDES_CTRL1, reg);
+}
+
 static int mv88e6393x_serdes_erratum_4_6(struct mv88e6xxx_chip *chip, int lane)
 {
        u16 reg;
@@ -1297,7 +1319,11 @@ static int mv88e6393x_serdes_erratum_4_6(struct mv88e6xxx_chip *chip, int lane)
        if (err)
                return err;
 
-       return mv88e6390_serdes_power_sgmii(chip, lane, false);
+       err = mv88e6390_serdes_power_sgmii(chip, lane, false);
+       if (err)
+               return err;
+
+       return mv88e6393x_serdes_power_lane(chip, lane, false);
 }
 
 int mv88e6393x_serdes_setup_errata(struct mv88e6xxx_chip *chip)
@@ -1362,17 +1388,29 @@ int mv88e6393x_serdes_power(struct mv88e6xxx_chip *chip, int port, int lane,
                err = mv88e6393x_serdes_erratum_4_8(chip, lane);
                if (err)
                        return err;
+
+               err = mv88e6393x_serdes_power_lane(chip, lane, true);
+               if (err)
+                       return err;
        }
 
        switch (cmode) {
        case MV88E6XXX_PORT_STS_CMODE_SGMII:
        case MV88E6XXX_PORT_STS_CMODE_1000BASEX:
        case MV88E6XXX_PORT_STS_CMODE_2500BASEX:
-               return mv88e6390_serdes_power_sgmii(chip, lane, on);
+               err = mv88e6390_serdes_power_sgmii(chip, lane, on);
+               break;
        case MV88E6393X_PORT_STS_CMODE_5GBASER:
        case MV88E6393X_PORT_STS_CMODE_10GBASER:
-               return mv88e6390_serdes_power_10g(chip, lane, on);
+               err = mv88e6390_serdes_power_10g(chip, lane, on);
+               break;
        }
 
-       return 0;
+       if (err)
+               return err;
+
+       if (!on)
+               err = mv88e6393x_serdes_power_lane(chip, lane, false);
+
+       return err;
 }

diff --git a/drivers/net/dsa/mv88e6xxx/serdes.h b/drivers/net/dsa/mv88e6xxx/serdes.h
index cbb3ba3..e9292c8 100644 (file)
--- a/drivers/net/dsa/mv88e6xxx/serdes.h
+++ b/drivers/net/dsa/mv88e6xxx/serdes.h
@@ -93,6 +93,9 @@
 #define MV88E6393X_SERDES_POC_PCS_MASK         0x0007
 #define MV88E6393X_SERDES_POC_RESET            BIT(15)
 #define MV88E6393X_SERDES_POC_PDOWN            BIT(5)
+#define MV88E6393X_SERDES_CTRL1                        0xf003
+#define MV88E6393X_SERDES_CTRL1_TX_PDOWN       BIT(9)
+#define MV88E6393X_SERDES_CTRL1_RX_PDOWN       BIT(8)
 
 #define MV88E6393X_ERRATA_4_8_REG              0xF074
 #define MV88E6393X_ERRATA_4_8_BIT              BIT(14)