net: ks8851: Use 16-bit read of RXFC register

The RXFC register is the only one being read using 8-bit accessors.
To make it easier to support the 16-bit accesses used by the parallel
bus variant of KS8851, use 16-bit accessor to read RXFC register as
well as neighboring RXFCTR register.

Remove ks8851_rdreg8() as it is not used anywhere anymore.

There should be no functional change.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Petr Stetiar <ynezz@true.cz>
Cc: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/micrel/ks8851.c

@@ -236,21 +236,6 @@ static void ks8851_rdreg(struct ks8851_net *ks, unsigned op,
 		memcpy(rxb, trx + 2, rxl);
 }
 
-/**
- * ks8851_rdreg8 - read 8 bit register from device
- * @ks: The chip information
- * @reg: The register address
- *
- * Read a 8bit register from the chip, returning the result
-*/
-static unsigned ks8851_rdreg8(struct ks8851_net *ks, unsigned reg)
-{
-	u8 rxb[1];
-
-	ks8851_rdreg(ks, MK_OP(1 << (reg & 3), reg), rxb, 1);
-	return rxb[0];
-}
-
 /**
  * ks8851_rdreg16 - read 16 bit register from device
  * @ks: The chip information
@@ -470,7 +455,7 @@ static void ks8851_rx_pkts(struct ks8851_net *ks)
 	unsigned rxstat;
 	u8 *rxpkt;
 
-	rxfc = ks8851_rdreg8(ks, KS_RXFC);
+	rxfc = (ks8851_rdreg16(ks, KS_RXFCTR) >> 8) & 0xff;
 
 	netif_dbg(ks, rx_status, ks->netdev,
 		  "%s: %d packets\n", __func__, rxfc);