net: dsa: sja1105: propagate exact error code from sja1105_dynamic_config_poll_valid()

Currently, sja1105_dynamic_config_wait_complete() returns either 0 or
-ETIMEDOUT, because it just looks at the read_poll_timeout() return code.

There will be future changes which move some more checks to
sja1105_dynamic_config_poll_valid(). It is important that we propagate
their exact return code (-ENOENT, -EINVAL), because callers of
sja1105_dynamic_config_read() depend on them.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: vladimiroltean

drivers/net/dsa/sja1105/sja1105_dynamic_config.c

@@ -1211,13 +1211,14 @@ sja1105_dynamic_config_wait_complete(struct sja1105_private *priv,
 				     struct sja1105_dyn_cmd *cmd,
 				     const struct sja1105_dynamic_table_ops *ops)
 {
-	int rc;
-
-	return read_poll_timeout(sja1105_dynamic_config_poll_valid,
-				 rc, rc != -EAGAIN,
-				 SJA1105_DYNAMIC_CONFIG_SLEEP_US,
-				 SJA1105_DYNAMIC_CONFIG_TIMEOUT_US,
-				 false, priv, cmd, ops);
+	int err, rc;
+
+	err = read_poll_timeout(sja1105_dynamic_config_poll_valid,
+				rc, rc != -EAGAIN,
+				SJA1105_DYNAMIC_CONFIG_SLEEP_US,
+				SJA1105_DYNAMIC_CONFIG_TIMEOUT_US,
+				false, priv, cmd, ops);
+	return err < 0 ? err : rc;
 }
 
 /* Provides read access to the settings through the dynamic interface