hwmon: (f71882fg) Acquire I/O regions while we're working with them

Acquire the I/O region for the Super I/O chip while we're working on it.
Signed-off-by: NGiel van Schijndel <me@mortis.eu>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

drivers/hwmon/f71882fg.c

@@ -2178,6 +2178,13 @@ static int __init f71882fg_find(int sioaddr, unsigned short *address,
 	int err = -ENODEV;
 	u16 devid;
 
+	/* Don't step on other drivers' I/O space by accident */
+	if (!request_region(sioaddr, 2, DRVNAME)) {
+		printk(KERN_ERR DRVNAME ": I/O address 0x%04x already in use\n",
+				(int)sioaddr);
+		return -EBUSY;
+	}
+
 	superio_enter(sioaddr);
 
 	devid = superio_inw(sioaddr, SIO_REG_MANID);
@@ -2232,6 +2239,7 @@ static int __init f71882fg_find(int sioaddr, unsigned short *address,
 		(int)superio_inb(sioaddr, SIO_REG_DEVREV));
 exit:
 	superio_exit(sioaddr);
+	release_region(sioaddr, 2);
 	return err;
 }