[PATCH 15/24 for-2.6.25] DM9000: Ensure spinlock held whilst accessing EEPROM registers

[Ben Dooks]

Ensure we hold the spinlock whilst the registers and being
modified even though we hold the overall lock. This should
protect against an interrupt happening whilst we are using
the device.

Signed-off-by: Ben Dooks <[EMAIL PROTECTED]>

Index: linux-2.6.24-quilt3/drivers/net/dm9000.c
===================================================================
--- linux-2.6.24-quilt3.orig/drivers/net/dm9000.c
+++ linux-2.6.24-quilt3/drivers/net/dm9000.c
@@ -1076,17 +1076,29 @@ dm9000_rx(struct net_device *dev)
 static void
 dm9000_read_eeprom(board_info_t *db, int offset, u8 *to)
 {
+       unsigned long flags;
+
        mutex_lock(&db->addr_lock);
 
+       spin_lock_irqsave(&db->lock, flags);
+
        iow(db, DM9000_EPAR, offset);
        iow(db, DM9000_EPCR, EPCR_ERPRR);
+
+       spin_unlock_irqrestore(&db->lock, flags);
+
        mdelay(8);              /* according to the datasheet 200us should be 
enough,
                                   but it doesn't work */
+
+       spin_lock_irqsave(&db->lock, flags);
+
        iow(db, DM9000_EPCR, 0x0);
 
        to[0] = ior(db, DM9000_EPDRL);
        to[1] = ior(db, DM9000_EPDRH);
 
+       spin_unlock_irqrestore(&db->lock, flags);
+
        mutex_unlock(&db->addr_lock);
 }
 
@@ -1096,14 +1108,22 @@ dm9000_read_eeprom(board_info_t *db, int
 static void
 dm9000_write_eeprom(board_info_t *db, int offset, u8 *data)
 {
+       unsigned long flags;
+
        mutex_lock(&db->addr_lock);
 
+       spin_lock_irqsave(&db->lock, flags);
        iow(db, DM9000_EPAR, offset);
        iow(db, DM9000_EPDRH, data[1]);
        iow(db, DM9000_EPDRL, data[0]);
        iow(db, DM9000_EPCR, EPCR_WEP | EPCR_ERPRW);
+       spin_unlock_irqrestore(&db->lock, flags);
+
        mdelay(8);              /* same shit */
+
+       spin_lock_irqsave(&db->lock, flags);
        iow(db, DM9000_EPCR, 0);
+       spin_unlock_irqrestore(&db->lock, flags);
 
        mutex_unlock(&db->addr_lock);
 }

-- 
Ben ([EMAIL PROTECTED], http://www.fluff.org/)

  'a smiley only costs 4 bytes'
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