From: Huang Shijie <b32955@freescale.com>
Date: Mon, 5 Dec 2011 10:53:47 +0000 (+0800)
Subject: ENGR00169433 IMX/UART : fix a bug in UART RX
X-Git-Tag: v3.0.35-fsl_4.1.0~1975
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d2967703c47bdcc9fa58b9895d7dcab1c31f74ec;p=karo-tx-linux.git

ENGR00169433 IMX/UART : fix a bug in UART RX

The origin code did not check the running situation.
It will cause a NULL pointer issue.

This patch fixes it.

Signed-off-by: Huang Shijie <b32955@freescale.com>
---

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index b9e169417c7b..f31fa1e16ca7 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -741,7 +741,9 @@ static void dma_rx_work(struct work_struct *w)
 		tty_flip_buffer_push(tty);
 		sport->rx_bytes = 0;
 	}
-	start_rx_dma(sport);
+
+	if (sport->dma_is_rxing)
+		start_rx_dma(sport);
 }
 
 /*