From 39469654db20a14915a7fb33ca2ec67547011ece Mon Sep 17 00:00:00 2001
From: Ben Dooks <ben.dooks@codethink.co.uk>
Date: Wed, 18 Nov 2015 14:41:19 +0000
Subject: ARM: meson: serial: check for tx-irq enabled in irq code

Ensure that if the interrupt handler is entered then only try and do tx
work if the tx irq is enabled.

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Tested-by: Carlo Caione <carlo@endlessm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 6c36526..b12a37b 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -237,8 +237,10 @@ static irqreturn_t meson_uart_interrupt(int irq, void *dev_id)
 	if (!(readl(port->membase + AML_UART_STATUS) & AML_UART_RX_EMPTY))
 		meson_receive_chars(port);
 
-	if (!(readl(port->membase + AML_UART_STATUS) & AML_UART_TX_FULL))
-		meson_uart_start_tx(port);
+	if (!(readl(port->membase + AML_UART_STATUS) & AML_UART_TX_FULL)) {
+		if (readl(port->membase + AML_UART_CONTROL) & AML_UART_TX_INT_EN)
+			meson_uart_start_tx(port);
+	}
 
 	spin_unlock(&port->lock);
 
-- 
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