netdev - [PATCH net-next] net: phy: improve get_phy

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Message-ID: <29affce3-f621-1c05-54bc-5fb87eeaa78f@gmail.com>
Date:   Wed, 16 Jan 2019 19:52:51 +0100
From:   Heiner Kallweit <hkallweit1@...il.com>
To:     Andrew Lunn <andrew@...n.ch>,
        Florian Fainelli <f.fainelli@...il.com>,
        David Miller <davem@...emloft.net>
Cc:     "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: [PATCH net-next] net: phy: improve get_phy_id

Only caller of get_phy_id() is get_phy_device(). There a PHY ID of
0xffffffff is translated back to -ENODEV. So we can avoid some
overhead by returning -ENODEV directly.

Signed-off-by: Heiner Kallweit <hkallweit1@...il.com>
---
 drivers/net/phy/phy_device.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index e61e9083f..b94095d74 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -755,15 +755,8 @@ static int get_phy_id(struct mii_bus *bus, int addr, u32 *phy_id,
 	/* Grab the bits from PHYIR1, and put them in the upper half */
 	phy_reg = mdiobus_read(bus, addr, MII_PHYSID1);
 	if (phy_reg < 0) {
-		/* if there is no device, return without an error so scanning
-		 * the bus works properly
-		 */
-		if (phy_reg == -EIO || phy_reg == -ENODEV) {
-			*phy_id = 0xffffffff;
-			return 0;
-		}
-
-		return -EIO;
+		/* returning -ENODEV doesn't stop bus scanning */
+		return (phy_reg == -EIO || phy_reg == -ENODEV) ? -ENODEV : -EIO;
 	}
 
 	*phy_id = (phy_reg & 0xffff) << 16;
-- 
2.20.1