firewire: Set correct buffer lengths for dualbuffer DMA descriptor.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c
index b5a1545..76ac70a 100644
--- a/drivers/firewire/fw-ohci.c
+++ b/drivers/firewire/fw-ohci.c
@@ -1583,10 +1583,7 @@
 					  descriptor_branch_always);
 		db->first_size = cpu_to_le16(ctx->base.header_size);
 		db->first_req_count = cpu_to_le16(p->header_length);
-		db->second_req_count = cpu_to_le16(p->payload_length);
-		db->first_res_count = cpu_to_le16(db->first_req_count);
-		db->second_res_count = cpu_to_le16(db->second_req_count);
-
+		db->first_res_count = db->first_req_count;
 		db->first_buffer = cpu_to_le32(d_bus + sizeof *db);
 		
 		if (offset + rest < PAGE_SIZE)
@@ -1594,6 +1591,8 @@
 		else
 			length = PAGE_SIZE - offset;
 
+		db->second_req_count = cpu_to_le16(length);
+		db->second_res_count = db->second_req_count;
 		page_bus = page_private(buffer->pages[page]);
 		db->second_buffer = cpu_to_le32(page_bus + offset);