netdev - [PATCH net v2] net: phy: smsc: fix printing too many logs

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Message-Id: <20200617183400.19386-1-zhengdejin5@gmail.com>
Date:   Thu, 18 Jun 2020 02:34:00 +0800
From:   Dejin Zheng <zhengdejin5@...il.com>
To:     andrew@...n.ch, f.fainelli@...il.com, hkallweit1@...il.com,
        linux@...linux.org.uk, davem@...emloft.net, kuba@...nel.org,
        netdev@...r.kernel.org
Cc:     linux-kernel@...r.kernel.org, Dejin Zheng <zhengdejin5@...il.com>,
        Kevin Groeneveld <kgroeneveld@...il.com>
Subject: [PATCH net v2] net: phy: smsc: fix printing too many logs

Commit 7ae7ad2f11ef47 ("net: phy: smsc: use phy_read_poll_timeout()
to simplify the code") will print a lot of logs as follows when Ethernet
cable is not connected:

[    4.473105] SMSC LAN8710/LAN8720 2188000.ethernet-1:00: lan87xx_read_status failed: -110

The commit will change the original behavior in smsc driver.
It does not has any error message whether it is timeout or
phy_read() fails, but this commit will changed it and print some
error messages by phy_read_poll_timeout() when it is timeout or
phy_read() fails. so use the read_poll_timeout() function to replace
phy_read_poll_timeout() for fix this issue. the read_poll_timeout()
function does not print any log when it goes wrong.

the original codes is that:

	/* Wait max 640 ms to detect energy */
	for (i = 0; i < 64; i++) {
	        /* Sleep to allow link test pulses to be sent */
	        msleep(10);
	        rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
	        if (rc < 0)
	                return rc;
	        if (rc & MII_LAN83C185_ENERGYON)
	                break;
	}

the commit 7ae7ad2f11ef47 ("net: phy: smsc: use phy_read_poll_timeout()
to simplify the code") modify it as this:

	phy_read_poll_timeout(phydev, MII_LAN83C185_CTRL_STATUS,
	                      rc & MII_LAN83C185_ENERGYON, 10000,
	                      640000, true);
	if (rc < 0)
	        return rc;

the phy_read_poll_timeout() will print a error log by phydev_err()
when timeout or rc < 0. read_poll_timeout() just return timeout
error and does not print any error log.

 #define phy_read_poll_timeout(phydev, regnum, val, cond, sleep_us, \
                                timeout_us, sleep_before_read) \
({ \
        int __ret = read_poll_timeout(phy_read, val, (cond) || val < 0, \
                sleep_us, timeout_us, sleep_before_read, phydev, regnum); \
        if (val <  0) \
                __ret = val; \
        if (__ret) \
                phydev_err(phydev, "%s failed: %d\n", __func__, __ret); \
        __ret; \
})

So use read_poll_timeout() to replace phy_read_poll_timeout() for
be consistent with the original code and fix this issue.

Fixes: 7ae7ad2f11ef47 ("net: phy: smsc: use phy_read_poll_timeout() to simplify the code")
Reported-by: Kevin Groeneveld <kgroeneveld@...il.com>
Signed-off-by: Dejin Zheng <zhengdejin5@...il.com>
---
v1 -> v2:
	- add more commit message spell out why has this commit
	  and how to modify it.

 drivers/net/phy/smsc.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c
index 93da7d3d0954..36c5a57917b8 100644
--- a/drivers/net/phy/smsc.c
+++ b/drivers/net/phy/smsc.c
@@ -123,9 +123,10 @@ static int lan87xx_read_status(struct phy_device *phydev)
 			return rc;
 
 		/* Wait max 640 ms to detect energy */
-		phy_read_poll_timeout(phydev, MII_LAN83C185_CTRL_STATUS, rc,
-				      rc & MII_LAN83C185_ENERGYON, 10000,
-				      640000, true);
+		read_poll_timeout(phy_read, rc,
+				  rc & MII_LAN83C185_ENERGYON || rc < 0,
+				  10000, 640000, true, phydev,
+				  MII_LAN83C185_CTRL_STATUS);
 		if (rc < 0)
 			return rc;
 
-- 
2.25.0