[PATCH v4 1/2] net: mtk_eth_soc: fix return value of MDIO operations

[Daniel Golle]

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.

Fixes: 656e705243fd0 ("net-next: mediatek: add support for MT7623 ethernet")
Signed-off-by: Daniel Golle <daniel at makrotopia.org>
---
v4: clean-up return values and types, split into two commits
v3: return -1 instead of 0xffff on error in _mtk_mdio_write
v2: use MII_DEVADDR_C45_SHIFT and MII_REGADDR_C45_MASK to extract
    device id and register address. Unify read and write functions to
    have identical types and parameter names where possible as we are
    anyway already replacing both function bodies.

 drivers/net/ethernet/mediatek/mtk_eth_soc.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index bcb91b01e69f5..0bf8d0a3b1781 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -94,11 +94,11 @@ 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;
 
@@ -108,17 +108,17 @@ static u32 _mtk_mdio_write(struct mtk_eth *eth, u32 phy_addr,
 		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, int phy_addr, int 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) |
@@ -126,7 +126,7 @@ 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;
+		return -EBUSY;
 
 	d = mtk_r32(eth, MTK_PHY_IAC) & 0xffff;
 
-- 
2.34.1