From 3ee82c6e41f3d2212647ce0bc5a05a0f69097824 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Mon, 11 Apr 2022 10:19:57 +0200
Subject: [PATCH] serial: imx: fix overrun interrupts in DMA mode
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Git-commit: 3ee82c6e41f3d2212647ce0bc5a05a0f69097824
Patch-mainline: v5.18-rc5
References: git-fixes
Commit 76821e222c18 ("serial: imx: ensure that RX irqs are off if RX is
off") accidentally enabled overrun interrupts unconditionally when
deferring DMA enable until after the receiver has been enabled during
startup.
Fix this by using the DMA-initialised instead of DMA-enabled flag to
determine whether overrun interrupts should be enabled.
Note that overrun interrupts are already accounted for in
imx_uart_clear_rx_errors() when using DMA since commit 41d98b5da92f
("serial: imx-serial - update RX error counters when DMA is used").
Fixes: 76821e222c18 ("serial: imx: ensure that RX irqs are off if RX is off")
Cc: stable@vger.kernel.org # 4.17
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20220411081957.7846-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/tty/serial/imx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index fd38e6ed4fda..a2100be8d554 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1448,7 +1448,7 @@ static int imx_uart_startup(struct uart_port *port)
imx_uart_writel(sport, ucr1, UCR1);
ucr4 = imx_uart_readl(sport, UCR4) & ~(UCR4_OREN | UCR4_INVR);
- if (!sport->dma_is_enabled)
+ if (!dma_is_inited)
ucr4 |= UCR4_OREN;
if (sport->inverted_rx)
ucr4 |= UCR4_INVR;
--
2.31.1