| Message ID | 20201022012516.18720-4-chris.packham@alliedtelesis.co.nz |
|---|---|
| State | Deferred |
| Delegated to: | David Miller |
| Headers | show |
| Series | net: dsa: mv88e6xxx: serdes link without phy | expand |
| Context | Check | Description |
|---|---|---|
| jkicinski/cover_letter | success | Link |
| jkicinski/fixes_present | success | Link |
| jkicinski/patch_count | success | Link |
| jkicinski/tree_selection | success | Guessed tree name to be net-next |
| jkicinski/subject_prefix | warning | Target tree name not specified in the subject |
| jkicinski/source_inline | success | Was 0 now: 0 |
| jkicinski/verify_signedoff | success | Link |
| jkicinski/module_param | success | Was 0 now: 0 |
| jkicinski/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| jkicinski/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| jkicinski/verify_fixes | success | Link |
| jkicinski/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 37 lines checked |
| jkicinski/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| jkicinski/header_inline | success | Link |
| jkicinski/stable | success | Stable not CCed |
On Thu, Oct 22, 2020 at 02:25:14PM +1300, Chris Packham wrote: > 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 <chris.packham@alliedtelesis.co.nz> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Andrew
diff --git a/drivers/net/dsa/mv88e6xxx/serdes.c b/drivers/net/dsa/mv88e6xxx/serdes.c index d4f40a739b17..ec9ca7210bb0 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; } } @@ -1049,6 +1051,7 @@ 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); @@ -1056,8 +1059,9 @@ 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; } }
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 <chris.packham@alliedtelesis.co.nz> --- Changes in v4: - new drivers/net/dsa/mv88e6xxx/serdes.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-)