From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Date: Wed, 28 Jan 2026 14:27:26 +0000 (+0100)
Subject: serial: 8250_port: Drop duplicate NULL check
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7885af04df6e4efd72910200c1bfc079d61202e4;p=thirdparty%2Fkernel%2Flinux.git

serial: 8250_port: Drop duplicate NULL check

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@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://patch.msgid.link/20260128142726.128175-1-andriy.shevchenko@linux.intel.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 cc94af2d578a..c05a6df8d6b4 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2364,8 +2364,8 @@ 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) {