FAILED: patch "[PATCH] serial: lantiq: add missing interrupt ack" failed to apply to 4.14-stable tree

The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.14.y
git checkout FETCH_HEAD
git cherry-pick -x 306320034e8fbe7ee1cc4f5269c55658b4612048
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2023061830-rubbed-stubble-2775@gregkh' --subject-prefix 'PATCH 4.14.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 306320034e8fbe7ee1cc4f5269c55658b4612048 Mon Sep 17 00:00:00 2001
From: Bernhard Seibold <[email protected]>
Date: Fri, 2 Jun 2023 15:30:29 +0200
Subject: [PATCH] serial: lantiq: add missing interrupt ack
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Currently, the error interrupt is never acknowledged, so once active it will stay active indefinitely, causing the handler to be called in an infinite loop.

Message-ID: <[email protected]>

index a58e9277dfad..f1387f1024db 100644
@@ -250,6 +250,7 @@ lqasc_err_int(int irq, void *_port)
 	struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
 
 	spin_lock_irqsave(&ltq_port->lock, flags);
+	__raw_writel(ASC_IRNCR_EIR, port->membase + LTQ_ASC_IRNCR);
 	/* clear any pending interrupts */
 	asc_update_bits(0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE |
 		ASCWHBSTATE_CLRROE, port->membase + LTQ_ASC_WHBSTATE);

commit 306320034e8fbe7ee1cc4f5269c55658b4612048 upstream.

Currently, the error interrupt is never acknowledged, so once active it will stay active indefinitely, causing the handler to be called in an infinite loop.

Message-ID: <[email protected]>

---
 drivers/tty/serial/lantiq.c | 2 ++
 1 file changed, 2 insertions(+)

index 22df94f107e5..345d8b3d4319 100644
@@ -1,3 +1,4 @@
+
 /*
  *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
  *

@@ -263,6 +264,7 @@ lqasc_err_int(int irq, void *_port)
 	unsigned long flags;
 	struct uart_port *port = (struct uart_port *)_port;
 	spin_lock_irqsave(&ltq_asc_lock, flags);
+	__raw_writel(ASC_IRNCR_EIR, port->membase + LTQ_ASC_IRNCR);
 	/* clear any pending interrupts */
 	ltq_w32_mask(0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE |
 		ASCWHBSTATE_CLRROE, port->membase + LTQ_ASC_WHBSTATE);

2.41.0

commit 306320034e8fbe7ee1cc4f5269c55658b4612048 upstream.

Currently, the error interrupt is never acknowledged, so once active it will stay active indefinitely, causing the handler to be called in an infinite loop.

Message-ID: <[email protected]>

---
 drivers/tty/serial/lantiq.c | 2 ++
 1 file changed, 2 insertions(+)

index 22df94f107e5..195b85176914 100644
@@ -1,3 +1,4 @@
+
 /*
  *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
  *

@@ -263,6 +264,7 @@ lqasc_err_int(int irq, void *_port)
 	unsigned long flags;
 	struct uart_port *port = (struct uart_port *)_port;
 	spin_lock_irqsave(&ltq_asc_lock, flags);
+	ltq_w32(ASC_IRNCR_EIR, port->membase + LTQ_ASC_IRNCR);
 	/* clear any pending interrupts */
 	ltq_w32_mask(0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE |
 		ASCWHBSTATE_CLRROE, port->membase + LTQ_ASC_WHBSTATE);

2.41.0

Thanks! Sorry, it was a bit too late at night.