[PATCH v7 1/2] net: ethernet: mtk_eth_soc: fix return value of MDIO ops

[Daniel Golle <daniel@makrotopia.org>]

Instead of returning -1 (-EPERM) when MDIO bus is stuck busy
while writing or 0xffff if it happens while reading, return the
appropriate -EBUSY. Also fix return type to int instead of u32
and remove an unneeded variable.

Fixes: 656e705243fd0 ("net-next: mediatek: add support for MT7623 ethernet")
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
v7: remove unneeded variable
v6: further clean up functions and more cleanly separate patches
v5: fix wrong variable name in first patch covered by follow-up patch
v4: clean-up return values and types, split into two commits

 drivers/net/ethernet/mediatek/mtk_eth_soc.c | 22 +++++++++------------
 1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index bcb91b01e69f5..72b3ae7b5ff8d 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -94,31 +94,29 @@ static int mtk_mdio_busy_wait(struct mtk_eth *eth)
 	return -1;
 }
 
-static u32 _mtk_mdio_write(struct mtk_eth *eth, u32 phy_addr,
-			   u32 phy_register, u32 write_data)
+static int _mtk_mdio_write(struct mtk_eth *eth, u32 phy_addr, u32 phy_reg,
+			   u32 write_data)
 {
 	if (mtk_mdio_busy_wait(eth))
-		return -1;
+		return -EBUSY;
 
 	write_data &= 0xffff;
 
 	mtk_w32(eth, PHY_IAC_ACCESS | PHY_IAC_START | PHY_IAC_WRITE |
-		(phy_register << PHY_IAC_REG_SHIFT) |
+		(phy_reg << PHY_IAC_REG_SHIFT) |
 		(phy_addr << PHY_IAC_ADDR_SHIFT) | write_data,
 		MTK_PHY_IAC);
 
 	if (mtk_mdio_busy_wait(eth))
-		return -1;
+		return -EBUSY;
 
 	return 0;
 }
 
-static u32 _mtk_mdio_read(struct mtk_eth *eth, int phy_addr, int phy_reg)
+static int _mtk_mdio_read(struct mtk_eth *eth, u32 phy_addr, u32 phy_reg)
 {
-	u32 d;
-
 	if (mtk_mdio_busy_wait(eth))
-		return 0xffff;
+		return -EBUSY;
 
 	mtk_w32(eth, PHY_IAC_ACCESS | PHY_IAC_START | PHY_IAC_READ |
 		(phy_reg << PHY_IAC_REG_SHIFT) |
@@ -126,11 +124,9 @@ static u32 _mtk_mdio_read(struct mtk_eth *eth, int phy_addr, int phy_reg)
 		MTK_PHY_IAC);
 
 	if (mtk_mdio_busy_wait(eth))
-		return 0xffff;
-
-	d = mtk_r32(eth, MTK_PHY_IAC) & 0xffff;
+		return -EBUSY;
 
-	return d;
+	return mtk_r32(eth, MTK_PHY_IAC) & 0xffff;
 }
 
 static int mtk_mdio_write(struct mii_bus *bus, int phy_addr,
-- 
2.34.1