Index: linux-2.6.25.3/drivers/i2c/i2c-core.c
===================================================================
--- linux-2.6.25.3.orig/drivers/i2c/i2c-core.c
+++ linux-2.6.25.3/drivers/i2c/i2c-core.c
@@ -1006,7 +1006,10 @@
 	if (addr < 0x03 || addr > 0x77) {
 		dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n",
 			 addr);
-		return -EINVAL;
+		/* however at least LM4857 (ab-)uses 0x7c,
+		 * thus need to specifically grant that */
+		if (addr != 0x7c)
+			return -EINVAL;
 	}
 
 	/* Skip if already in use */