DM9000: Add platform flag for no attached EEPROM

Allow the platform data to specify to the DM9000 driver
that there is no posibility of an attached EEPROM on the
device, so default all reads to 0xff and ignore any
write operations.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

drivers/net/dm9000.c

@@ -405,6 +405,9 @@ static int dm9000_get_eeprom(struct net_device *dev,
 	if ((len & 1) != 0 || (offset & 1) != 0)
 		return -EINVAL;
 
+	if (dm->flags & DM9000_PLATF_NO_EEPROM)
+		return -ENOENT;
+
 	ee->magic = DM_EEPROM_MAGIC;
 
 	for (i = 0; i < len; i += 2)
@@ -426,6 +429,9 @@ static int dm9000_set_eeprom(struct net_device *dev,
 	if ((len & 1) != 0 || (offset & 1) != 0)
 		return -EINVAL;
 
+	if (dm->flags & DM9000_PLATF_NO_EEPROM)
+		return -ENOENT;
+
 	if (ee->magic != DM_EEPROM_MAGIC)
 		return -EINVAL;
 
@@ -1100,6 +1106,12 @@ dm9000_read_eeprom(board_info_t *db, int offset, u8 *to)
 {
 	unsigned long flags;
 
+	if (db->flags & DM9000_PLATF_NO_EEPROM) {
+		to[0] = 0xff;
+		to[1] = 0xff;
+		return;
+	}
+
 	mutex_lock(&db->addr_lock);
 
 	spin_lock_irqsave(&db->lock, flags);
@@ -1134,6 +1146,9 @@ dm9000_write_eeprom(board_info_t *db, int offset, u8 *data)
 {
 	unsigned long flags;
 
+	if (db->flags & DM9000_PLATF_NO_EEPROM)
+		return;
+
 	mutex_lock(&db->addr_lock);
 
 	spin_lock_irqsave(&db->lock, flags);

include/linux/dm9000.h

@@ -20,6 +20,7 @@
 #define DM9000_PLATF_16BITONLY	(0x0002)
 #define DM9000_PLATF_32BITONLY	(0x0004)
 #define DM9000_PLATF_EXT_PHY	(0x0008)
+#define DM9000_PLATF_NO_EEPROM	(0x0010)
 
 /* platfrom data for platfrom device structure's platfrom_data field */