From: Antoine Tenart <antoine.tenart@bootlin.com>
Date: Wed, 19 Sep 2018 11:27:03 +0200
Subject: net: mvpp2: do not update the queue mode while probing
Patch-mainline: v4.20-rc1
Git-commit: fd4a1056884e191948550a674072ba78b19f420b
References: bsc#1119113 FATE#326472

This patch updates the probing function so that the queue mode isn't
updated while probing, as the driver would silently end up using a
configuration not wanted by the user. The patch adds an extra check to
validate the chosen queue mode instead, and the driver will fail to
probe if the configuration is invalid.

Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c |   17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -4244,6 +4244,10 @@ static bool mvpp2_port_has_irqs(struct m
 	char name[5];
 	int i;
 
+	/* ACPI */
+	if (!port_node)
+		return true;
+
 	if (priv->hw_version == MVPP21)
 		return false;
 
@@ -4638,16 +4642,13 @@ static int mvpp2_port_probe(struct platf
 	int phy_mode;
 	int err, i, cpu;
 
-	if (port_node) {
-		has_tx_irqs = mvpp2_port_has_irqs(priv, port_node, &flags);
-	} else {
-		has_tx_irqs = true;
-		queue_mode = MVPP2_QDIST_MULTI_MODE;
+	has_tx_irqs = mvpp2_port_has_irqs(priv, port_node, &flags);
+	if (!has_tx_irqs && queue_mode == MVPP2_QDIST_MULTI_MODE) {
+		dev_err(&pdev->dev,
+			"not enough IRQs to support multi queue mode\n");
+		return -EINVAL;
 	}
 
-	if (!has_tx_irqs)
-		queue_mode = MVPP2_QDIST_SINGLE_MODE;
-
 	ntxqs = MVPP2_MAX_TXQ;
 	if (priv->hw_version == MVPP22 && queue_mode == MVPP2_QDIST_MULTI_MODE)
 		nrxqs = MVPP2_DEFAULT_RXQ * num_possible_cpus();