[PATCH v1 1/1] serial: 8250_port: Drop duplicate NULL check

[Andy Shevchenko]

serial8250_release_dma() is NULL-aware, no need to check this in the caller.
While at it, make sure DMA won't be used again, by NULLifying the pointer.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
 drivers/tty/serial/8250/8250_port.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 21fdf84f118f..c40d750d5a4b 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2366,8 +2366,8 @@ void serial8250_do_shutdown(struct uart_port *port)
 
 	synchronize_irq(port->irq);
 
-	if (up->dma)
-		serial8250_release_dma(up);
+	serial8250_release_dma(up);
+	up->dma = NULL;
 
 	scoped_guard(uart_port_lock_irqsave, port) {
 		if (port->flags & UPF_FOURPORT) {
-- 
2.50.1