ravb: Add gstrings_stats and gstrings_size to struct ravb_hw_info

The device stats strings for R-Car and RZ/G2L are different.

R-Car provides 30 device stats, whereas RZ/G2L provides only 15. In
addition, RZ/G2L has stats "rx_queue_0_csum_offload_errors" instead of
"rx_queue_0_missed_errors".

Add structure variables gstrings_stats and gstrings_size to struct
ravb_hw_info, so that subsequent SoCs can be added without any code
changes in the ravb_get_strings function.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Sergei Shtylyov <sergei.shtylyov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/renesas/ravb.h

@@ -989,6 +989,8 @@ enum ravb_chip_id {
 };
 
 struct ravb_hw_info {
+	const char (*gstrings_stats)[ETH_GSTRING_LEN];
+	size_t gstrings_size;
 	enum ravb_chip_id chip_id;
 	int stats_len;
 	size_t max_rx_len;

drivers/net/ethernet/renesas/ravb_main.c

@@ -1177,9 +1177,12 @@ static void ravb_get_ethtool_stats(struct net_device *ndev,
 
 static void ravb_get_strings(struct net_device *ndev, u32 stringset, u8 *data)
 {
+	struct ravb_private *priv = netdev_priv(ndev);
+	const struct ravb_hw_info *info = priv->info;
+
 	switch (stringset) {
 	case ETH_SS_STATS:
-		memcpy(data, ravb_gstrings_stats, sizeof(ravb_gstrings_stats));
+		memcpy(data, info->gstrings_stats, info->gstrings_size);
 		break;
 	}
 }
@@ -1926,12 +1929,16 @@ static int ravb_mdio_release(struct ravb_private *priv)
 }
 
 static const struct ravb_hw_info ravb_gen3_hw_info = {
+	.gstrings_stats = ravb_gstrings_stats,
+	.gstrings_size = sizeof(ravb_gstrings_stats),
 	.chip_id = RCAR_GEN3,
 	.stats_len = ARRAY_SIZE(ravb_gstrings_stats),
 	.max_rx_len = RX_BUF_SZ + RAVB_ALIGN - 1,
 };
 
 static const struct ravb_hw_info ravb_gen2_hw_info = {
+	.gstrings_stats = ravb_gstrings_stats,
+	.gstrings_size = sizeof(ravb_gstrings_stats),
 	.chip_id = RCAR_GEN2,
 	.stats_len = ARRAY_SIZE(ravb_gstrings_stats),
 	.max_rx_len = RX_BUF_SZ + RAVB_ALIGN - 1,