[E100]: Add module option to ignore bad EEPROM checksums.

Several people run into the situation where the E100
EEPROM contents are fine, but the checksum hasn't been
set properly.  This renders the device useless for
them even though it would function correctly.

The default is off, which retains the current behavior.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/e100.c b/drivers/net/e100.c
index 91ef5f2..ce850f1 100644
--- a/drivers/net/e100.c
+++ b/drivers/net/e100.c
@@ -173,8 +173,11 @@
 MODULE_VERSION(DRV_VERSION);
 
 static int debug = 3;
+static int eeprom_bad_csum_allow = 0;
 module_param(debug, int, 0);
+module_param(eeprom_bad_csum_allow, int, 0);
 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
+MODULE_PARM_DESC(eeprom_bad_csum_allow, "Allow bad eeprom checksums");
 #define DPRINTK(nlevel, klevel, fmt, args...) \
 	(void)((NETIF_MSG_##nlevel & nic->msg_enable) && \
 	printk(KERN_##klevel PFX "%s: %s: " fmt, nic->netdev->name, \
@@ -756,7 +759,8 @@
 	checksum = le16_to_cpu(0xBABA - checksum);
 	if(checksum != nic->eeprom[nic->eeprom_wc - 1]) {
 		DPRINTK(PROBE, ERR, "EEPROM corrupted\n");
-		return -EAGAIN;
+		if (!eeprom_bad_csum_allow)
+			return -EAGAIN;
 	}
 
 	return 0;