diff --git a/[refs] b/[refs]
index cb1f043b196c..fbbf694d7547 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ddc80bd781590ef6eb8ce30a0f3ac88c5599e41c
+refs/heads/master: 2f4d4da8f82c2598b8713f4a01f360f3751d90be
diff --git a/trunk/drivers/serial/mpsc.c b/trunk/drivers/serial/mpsc.c
index d09f2097d5b0..00924feaf621 100644
--- a/trunk/drivers/serial/mpsc.c
+++ b/trunk/drivers/serial/mpsc.c
@@ -503,7 +503,8 @@ mpsc_sdma_intr_ack(struct mpsc_port_info *pi)
 
 	if (pi->mirror_regs)
 		pi->shared_regs->SDMA_INTR_CAUSE_m = 0;
-	writel(0, pi->shared_regs->sdma_intr_base + SDMA_INTR_CAUSE);
+	writeb(0x00, pi->shared_regs->sdma_intr_base + SDMA_INTR_CAUSE +
+	       pi->port.line);
 	return;
 }