r8152: fix the sw rx checksum is unavailable

Fix the hw rx checksum is always enabled, and the user couldn't switch
it to sw rx checksum.

Note that the RTL_VER_01 only support sw rx checksum only. Besides,
the hw rx checksum for RTL_VER_02 is disabled after
commit b9a321b4 ("r8152: Fix broken RX checksums."). Re-enable it.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/usb/r8152.c

@@ -1730,7 +1730,7 @@ static u8 r8152_rx_csum(struct r8152 *tp, struct rx_desc *rx_desc)
 	u8 checksum = CHECKSUM_NONE;
 	u32 opts2, opts3;
 
-	if (tp->version == RTL_VER_01 || tp->version == RTL_VER_02)
+	if (!(tp->netdev->features & NETIF_F_RXCSUM))
 		goto return_result;
 
 	opts2 = le32_to_cpu(rx_desc->opts2);
@@ -4356,6 +4356,11 @@ static int rtl8152_probe(struct usb_interface *intf,
 				NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
 				NETIF_F_IPV6_CSUM | NETIF_F_TSO6;
 
+	if (tp->version == RTL_VER_01) {
+		netdev->features &= ~NETIF_F_RXCSUM;
+		netdev->hw_features &= ~NETIF_F_RXCSUM;
+	}
+
 	netdev->ethtool_ops = &ops;
 	netif_set_gso_max_size(netdev, RTL_LIMITED_TSO_SIZE);