e1000e: additional error handling on PHY register accesses
PHY reads/writes via the MDIC register could potentially return results
from a previous PHY register access. If that happens, the offset in the
returned results will be that of the previous access and if that is
different from the expected offset, log a debug message and error out.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/e1000e/phy.c b/drivers/net/ethernet/intel/e1000e/phy.c
index 60dbf02..cbb310f 100644
--- a/drivers/net/ethernet/intel/e1000e/phy.c
+++ b/drivers/net/ethernet/intel/e1000e/phy.c
@@ -178,6 +178,12 @@
e_dbg("MDI Error\n");
return -E1000_ERR_PHY;
}
+ if (((mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT) != offset) {
+ e_dbg("MDI Read offset error - requested %d, returned %d\n",
+ offset,
+ (mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT);
+ return -E1000_ERR_PHY;
+ }
*data = (u16)mdic;
/* Allow some time after each MDIC transaction to avoid
@@ -236,6 +242,12 @@
e_dbg("MDI Error\n");
return -E1000_ERR_PHY;
}
+ if (((mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT) != offset) {
+ e_dbg("MDI Write offset error - requested %d, returned %d\n",
+ offset,
+ (mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT);
+ return -E1000_ERR_PHY;
+ }
/* Allow some time after each MDIC transaction to avoid
* reading duplicate data in the next MDIC transaction.