From: Peter Hurley <peter@hurleysoftware.com>
Date: Sun, 10 Jan 2016 22:39:35 +0000 (-0800)
Subject: serial: 8250: Wait for irq to complete before shutdown
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=611e0d83a83724340d4bf0eed610af01401b2ff4;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

serial: 8250: Wait for irq to complete before shutdown

After masking all interrupts, wait for the irq handler to complete
before continuing shutdown.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 9ef77a52c4f2..57b3a80b4359 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2088,8 +2088,12 @@ void serial8250_do_shutdown(struct uart_port *port)
 	/*
 	 * Disable interrupts from this port
 	 */
+	spin_lock_irqsave(&port->lock, flags);
 	up->ier = 0;
 	serial_port_out(port, UART_IER, 0);
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	synchronize_irq(port->irq);
 
 	if (up->dma)
 		serial8250_release_dma(up);