From 0fd5d79efa4a35c5b0944f7dc42b440d56af4b04 Mon Sep 17 00:00:00 2001 From: Chris Packham Date: Tue, 24 Nov 2020 17:34:40 +1300 Subject: net: dsa: mv88e6xxx: Handle error in serdes_get_regs If the underlying read operation failed we would end up writing stale data to the supplied buffer. This would end up with the last successfully read value repeating. Fix this by only writing the data when we know the read was good. This will mean that failed values will return 0xffff. Signed-off-by: Chris Packham Reviewed-by: Andrew Lunn Signed-off-by: Jakub Kicinski --- drivers/net/dsa/mv88e6xxx/serdes.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) (limited to 'drivers/net/dsa/mv88e6xxx/serdes.c') diff --git a/drivers/net/dsa/mv88e6xxx/serdes.c b/drivers/net/dsa/mv88e6xxx/serdes.c index e60e8f0d0225..3195936dc5be 100644 --- a/drivers/net/dsa/mv88e6xxx/serdes.c +++ b/drivers/net/dsa/mv88e6xxx/serdes.c @@ -400,14 +400,16 @@ void mv88e6352_serdes_get_regs(struct mv88e6xxx_chip *chip, int port, void *_p) { u16 *p = _p; u16 reg; + int err; int i; if (!mv88e6352_port_has_serdes(chip, port)) return; for (i = 0 ; i < 32; i++) { - mv88e6352_serdes_read(chip, i, ®); - p[i] = reg; + err = mv88e6352_serdes_read(chip, i, ®); + if (!err) + p[i] = reg; } } @@ -1096,6 +1098,7 @@ void mv88e6390_serdes_get_regs(struct mv88e6xxx_chip *chip, int port, void *_p) u16 *p = _p; int lane; u16 reg; + int err; int i; lane = mv88e6xxx_serdes_get_lane(chip, port); @@ -1103,8 +1106,9 @@ void mv88e6390_serdes_get_regs(struct mv88e6xxx_chip *chip, int port, void *_p) return; for (i = 0 ; i < ARRAY_SIZE(mv88e6390_serdes_regs); i++) { - mv88e6390_serdes_read(chip, lane, MDIO_MMD_PHYXS, - mv88e6390_serdes_regs[i], ®); - p[i] = reg; + err = mv88e6390_serdes_read(chip, lane, MDIO_MMD_PHYXS, + mv88e6390_serdes_regs[i], ®); + if (!err) + p[i] = reg; } } -- cgit