[PATCH net-next v7 07/17] net: macb: refuse set_ringparam on EMAC

EMAC has never supported changing ring sizes: RX is hardcoded to 9 and
TX is the tiniest ring buffer you can imagine.

Make sure the operation fails early rather than silently succeed and
storing values in bp->configured_{rx,tx}_ring_size that are never read
in the EMAC case.

Signed-off-by: Théo Lebrun <[email protected]>
---
 drivers/net/ethernet/cadence/macb_main.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index af351d30adab..1476bce77f34 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -3687,6 +3687,9 @@ static int macb_set_ringparam(struct net_device *netdev,
 	u32 new_rx_size, new_tx_size;
 	unsigned int reset = 0;
 
+	if (bp->caps & MACB_CAPS_MACB_IS_EMAC)
+		return -EOPNOTSUPP;
+
 	if ((ring->rx_mini_pending) || (ring->rx_jumbo_pending))
 		return -EINVAL;
 

-- 
2.55.0