[PATCH] serial: imx: Enable RTSD only when needed

* [PATCH] serial: imx: Enable RTSD only when needed
@ 2017-04-12 13:30 Romain Perier
  2017-04-12 13:38 ` Fabio Estevam
  0 siblings, 1 reply; 3+ messages in thread
From: Romain Perier @ 2017-04-12 13:30 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Romain Perier, linux-arm-kernel, linux-serial, Nandor Han

From: Nandor Han <nandor.han@ge.com>

Currently, this IRQ is always enabled. Some devices might mux these pins
to other I/Os, like I2C. This could lead to spurious interrupts.

This commit makes this IRQ optional, by using the field have_rtscts.

Signed-off-by: Nandor Han <nandor.han@ge.com>
Signed-off-by: Romain Perier <romain.perier@collabora.com>
---
 drivers/tty/serial/imx.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index e3e152cb..6dd674f 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1294,7 +1294,9 @@ static int imx_startup(struct uart_port *port)
 		imx_enable_dma(sport);
 
 	temp = readl(sport->port.membase + UCR1);
-	temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN;
+	temp |= UCR1_RRDYEN | UCR1_UARTEN;
+	if (sport->have_rtscts)
+			temp |= UCR1_RTSDEN;
 
 	writel(temp, sport->port.membase + UCR1);
 
-- 
2.9.3

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