net: dsa: mv88e6xxx: error handling for serdes_power functions

commit 0416e7af2369b0d12a28dea8d30b104df9a6953d upstream.

Added default case to handle undefined cmode scenario in
mv88e6393x_serdes_power() and mv88e6393x_serdes_power() methods.

Addresses-Coverity: 1494644 ("Uninitialized scalar variable")
Fixes: 21635d9203e1c (net: dsa: mv88e6xxx: Fix application of erratum 4.8 for 88E6393X)
Reviewed-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Ameer Hamza <amhamza.mgc@gmail.com>
Link: https://lore.kernel.org/r/20211209041552.9810-1-amhamza.mgc@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/dsa/mv88e6xxx/serdes.c b/drivers/net/dsa/mv88e6xxx/serdes.c
index 55273013bfb55c5b59a72b6b7fdaff0c1c508915..2b05ead515cdcbe756ec4d34d67e823912174e49 100644 (file)
--- a/drivers/net/dsa/mv88e6xxx/serdes.c
+++ b/drivers/net/dsa/mv88e6xxx/serdes.c
@@ -830,7 +830,7 @@ int mv88e6390_serdes_power(struct mv88e6xxx_chip *chip, int port, int lane,
                           bool up)
 {
        u8 cmode = chip->ports[port].cmode;
-       int err = 0;
+       int err;
 
        switch (cmode) {
        case MV88E6XXX_PORT_STS_CMODE_SGMII:
@@ -842,6 +842,9 @@ int mv88e6390_serdes_power(struct mv88e6xxx_chip *chip, int port, int lane,
        case MV88E6XXX_PORT_STS_CMODE_RXAUI:
                err = mv88e6390_serdes_power_10g(chip, lane, up);
                break;
+       default:
+               err = -EINVAL;
+               break;
        }
 
        if (!err && up)
@@ -1541,6 +1544,9 @@ int mv88e6393x_serdes_power(struct mv88e6xxx_chip *chip, int port, int lane,
        case MV88E6393X_PORT_STS_CMODE_10GBASER:
                err = mv88e6390_serdes_power_10g(chip, lane, on);
                break;
+       default:
+               err = -EINVAL;
+               break;
        }
 
        if (err)