[PATCH 5.15 023/110] smsc95xx: Ignore -ENODEV errors when device is unplugged

Greg Kroah-Hartman
2022-03-14T12:12:20Z

From: Fabio Estevam <festevam@denx.de>

[ Upstream commit c70c453abcbf3ecbaadd4c3236a5119b8da365cf ]

According to Documentation/driver-api/usb/URB.rst when a device
is unplugged usb_submit_urb() returns -ENODEV.

This error code propagates all the way up to usbnet_read_cmd() and
usbnet_write_cmd() calls inside the smsc95xx.c driver during
Ethernet cable unplug, unbind or reboot.

This causes the following errors to be shown on reboot, for example:

ci_hdrc ci_hdrc.1: remove, state 1
usb usb2: USB disconnect, device number 1
usb 2-1: USB disconnect, device number 2
usb 2-1.1: USB disconnect, device number 3
smsc95xx 2-1.1:1.0 eth1: unregister 'smsc95xx' usb-ci_hdrc.1-1.1, smsc95xx USB 2.0 Ethernet
smsc95xx 2-1.1:1.0 eth1: Failed to read reg index 0x00000114: -19
smsc95xx 2-1.1:1.0 eth1: Error reading MII_ACCESS
smsc95xx 2-1.1:1.0 eth1: __smsc95xx_mdio_read: MII is busy
smsc95xx 2-1.1:1.0 eth1: Failed to read reg index 0x00000114: -19
smsc95xx 2-1.1:1.0 eth1: Error reading MII_ACCESS
smsc95xx 2-1.1:1.0 eth1: __smsc95xx_mdio_read: MII is busy
smsc95xx 2-1.1:1.0 eth1: hardware isn't capable of remote wakeup
usb 2-1.4: USB disconnect, device number 4
ci_hdrc ci_hdrc.1: USB bus 2 deregistered
ci_hdrc ci_hdrc.0: remove, state 4
usb usb1: USB disconnect, device number 1
ci_hdrc ci_hdrc.0: USB bus 1 deregistered
imx2-wdt 30280000.watchdog: Device shutdown: Expect reboot!
reboot: Restarting system

Ignore the -ENODEV errors inside __smsc95xx_mdio_read() and
__smsc95xx_phy_wait_not_busy() and do not print error messages
when -ENODEV is returned.

Fixes: a049a30fc27c ("net: usb: Correct PHY handling of smsc95xx")
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/usb/smsc95xx.c | 28 ++++++++++++++++++++--------
1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c
index 026e7487c45b..eb0d325e92b7 100644
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -84,9 +84,10 @@ static int __must_check __smsc95xx_read_reg(struct usbnet *dev, u32 index,
ret = fn(dev, USB_VENDOR_REQUEST_READ_REGISTER, USB_DIR_IN
| USB_TYPE_VENDOR | USB_RECIP_DEVICE,
0, index, &buf, 4);
- if (unlikely(ret < 0)) {
- netdev_warn(dev->net, "Failed to read reg index 0x%08x: %d\n",
- index, ret);
+ if (ret < 0) {
+ if (ret != -ENODEV)
+ netdev_warn(dev->net, "Failed to read reg index 0x%08x: %d\n",
+ index, ret);
return ret;
}

@@ -116,7 +117,7 @@ static int __must_check __smsc95xx_write_reg(struct usbnet *dev, u32 index,
ret = fn(dev, USB_VENDOR_REQUEST_WRITE_REGISTER, USB_DIR_OUT
| USB_TYPE_VENDOR | USB_RECIP_DEVICE,
0, index, &buf, 4);
- if (unlikely(ret < 0))
+ if (ret < 0 && ret != -ENODEV)
netdev_warn(dev->net, "Failed to write reg index 0x%08x: %d\n",
index, ret);

@@ -159,6 +160,9 @@ static int __must_check __smsc95xx_phy_wait_not_busy(struct usbnet *dev,
do {
ret = __smsc95xx_read_reg(dev, MII_ADDR, &val, in_pm);
if (ret < 0) {
+ /* Ignore -ENODEV error during disconnect() */
+ if (ret == -ENODEV)
+ return 0;
netdev_warn(dev->net, "Error reading MII_ACCESS\n");
return ret;
}
@@ -194,7 +198,8 @@ static int __smsc95xx_mdio_read(struct usbnet *dev, int phy_id, int idx,
addr = mii_address_cmd(phy_id, idx, MII_READ_ | MII_BUSY_);
ret = __smsc95xx_write_reg(dev, MII_ADDR, addr, in_pm);
if (ret < 0) {
- netdev_warn(dev->net, "Error writing MII_ADDR\n");
+ if (ret != -ENODEV)
+ netdev_warn(dev->net, "Error writing MII_ADDR\n");
goto done;
}

@@ -206,7 +211,8 @@ static int __smsc95xx_mdio_read(struct usbnet *dev, int phy_id, int idx,

ret = __smsc95xx_read_reg(dev, MII_DATA, &val, in_pm);
if (ret < 0) {
- netdev_warn(dev->net, "Error reading MII_DATA\n");
+ if (ret != -ENODEV)
+ netdev_warn(dev->net, "Error reading MII_DATA\n");
goto done;
}

@@ -214,6 +220,10 @@ static int __smsc95xx_mdio_read(struct usbnet *dev, int phy_id, int idx,

done:
mutex_unlock(&dev->phy_mutex);
+
+ /* Ignore -ENODEV error during disconnect() */
+ if (ret == -ENODEV)
+ return 0;
return ret;
}

@@ -235,7 +245,8 @@ static void __smsc95xx_mdio_write(struct usbnet *dev, int phy_id,
val = regval;
ret = __smsc95xx_write_reg(dev, MII_DATA, val, in_pm);
if (ret < 0) {
- netdev_warn(dev->net, "Error writing MII_DATA\n");
+ if (ret != -ENODEV)
+ netdev_warn(dev->net, "Error writing MII_DATA\n");
goto done;
}

@@ -243,7 +254,8 @@ static void __smsc95xx_mdio_write(struct usbnet *dev, int phy_id,
addr = mii_address_cmd(phy_id, idx, MII_WRITE_ | MII_BUSY_);
ret = __smsc95xx_write_reg(dev, MII_ADDR, addr, in_pm);
if (ret < 0) {
- netdev_warn(dev->net, "Error writing MII_ADDR\n");
+ if (ret != -ENODEV)
+ netdev_warn(dev->net, "Error writing MII_ADDR\n");
goto done;
}

--
2.34.1