From: Fabian Godehardt <fg@emlix.com>
Date: Thu, 11 Jun 2009 13:38:38 +0000 (+0100)
Subject: imx: serial: be sure to stop xmit upon shutdown
X-Git-Tag: firefly_0821_release~13989^2~6
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=2e1463922a35584c863f71d4021e1e71f76eaed0;p=firefly-linux-kernel-4.4.55.git

imx: serial: be sure to stop xmit upon shutdown

needed to avoid continued transmission by hardware
while software already shuts down, which might
cause dangling characters to show up in hardware
queues when restarting the device.

Signed-off-by: Fabian Godehardt <fg@emlix.com>
Signed-off-by: Oskar Schirmer <os@emlix.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/drivers/serial/imx.c b/drivers/serial/imx.c
index 49f2e12ba58d..e6c2ba26dcbb 100644
--- a/drivers/serial/imx.c
+++ b/drivers/serial/imx.c
@@ -634,6 +634,10 @@ static void imx_shutdown(struct uart_port *port)
 	struct imx_port *sport = (struct imx_port *)port;
 	unsigned long temp;
 
+	temp = readl(sport->port.membase + UCR2);
+	temp &= ~(UCR2_TXEN);
+	writel(temp, sport->port.membase + UCR2);
+
 	/*
 	 * Stop our timer.
 	 */