diff --git a/drivers/spi/ich.c b/drivers/spi/ich.c
index ef1ce1d..8865df5 100644
--- a/drivers/spi/ich.c
+++ b/drivers/spi/ich.c
@@ -147,6 +147,11 @@
 		return NULL;
 	}
 
+	/*
+	 * Yes this controller can only write a small number of bytes at
+	 * once! The limit is typically 64 bytes.
+	 */
+	ich->slave.max_write_size = ctlr.databytes;
 	ich->speed = max_hz;
 
 	return &ich->slave;