usbnet: smsc95xx: Don't reset PHY behind PHY driver's back

smsc95xx_reset() resets the PHY behind the PHY driver's back, which
seems like a bad idea generally.  Remove that portion of the function.

We're about to use PHY interrupts instead of polling to detect link
changes on SMSC LAN95xx chips.  Because smsc95xx_reset() is called from
usbnet_open(), PHY interrupt settings are lost whenever the net_device
is brought up.

There are two other callers of smsc95xx_reset(), namely smsc95xx_bind()
and smsc95xx_reset_resume(), and both may indeed benefit from a PHY
reset.  However they already perform one through their calls to
phy_connect_direct() and phy_init_hw().

Tested-by: Oleksij Rempel <o.rempel@pengutronix.de> # LAN9514/9512/9500
Tested-by: Ferry Toth <fntoth@gmail.com> # LAN9514
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Martyn Welch <martyn.welch@collabora.com>
Cc: Gabriel Hojda <ghojda@yo2urs.ro>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/usb/smsc95xx.c

@@ -887,24 +887,6 @@ static int smsc95xx_reset(struct usbnet *dev)
 		return ret;
 	}
 
-	ret = smsc95xx_write_reg(dev, PM_CTRL, PM_CTL_PHY_RST_);
-	if (ret < 0)
-		return ret;
-
-	timeout = 0;
-	do {
-		msleep(10);
-		ret = smsc95xx_read_reg(dev, PM_CTRL, &read_buf);
-		if (ret < 0)
-			return ret;
-		timeout++;
-	} while ((read_buf & PM_CTL_PHY_RST_) && (timeout < 100));
-
-	if (timeout >= 100) {
-		netdev_warn(dev->net, "timeout waiting for PHY Reset\n");
-		return ret;
-	}
-
 	ret = smsc95xx_set_mac_address(dev);
 	if (ret < 0)
 		return ret;