cxgb4: Enhance driver to update FW, when FW is too old

t4_check_fw_version() can return several error codes (-EINVAL, -EBUSY,
-EAGAIN). The present code sets the adapter state to UNINIT only if its
an EFAULT. In all the error cases set the adapter to uninitialized state.

In t4_check_fw_version() if call to t4_get_fw_version() fails, repeat the
operation a few times before returning failure.
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c

@@ -3698,7 +3698,7 @@ static int adap_init0(struct adapter *adap)
 	t4_get_tp_version(adap, &adap->params.tp_vers);
 	ret = t4_check_fw_version(adap);
 	/* If firmware is too old (not supported by driver) force an update. */
-	if (ret == -EFAULT)
+	if (ret)
 		state = DEV_STATE_UNINIT;
 	if ((adap->flags & MASTER_PF) && state != DEV_STATE_INIT) {
 		struct fw_info *fw_info;

drivers/net/ethernet/chelsio/cxgb4/t4_hw.c

@@ -2981,11 +2981,15 @@ int t4_get_exprom_version(struct adapter *adap, u32 *vers)
  */
 int t4_check_fw_version(struct adapter *adap)
 {
-	int ret, major, minor, micro;
+	int i, ret, major, minor, micro;
 	int exp_major, exp_minor, exp_micro;
 	unsigned int chip_version = CHELSIO_CHIP_VERSION(adap->params.chip);
 
 	ret = t4_get_fw_version(adap, &adap->params.fw_vers);
+	/* Try multiple times before returning error */
+	for (i = 0; (ret == -EBUSY || ret == -EAGAIN) && i < 3; i++)
+		ret = t4_get_fw_version(adap, &adap->params.fw_vers);
+
 	if (ret)
 		return ret;