LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Sherry Sun <sherry.sun@nxp.com>
To: gregkh@linuxfoundation.org, jirislaby@kernel.org
Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-imx@nxp.com
Subject: [PATCH] tty: serial: fsl_lpuart: check dma_tx_in_progress in tx dma callback
Date: Tue, 17 Aug 2021 18:02:03 +0800	[thread overview]
Message-ID: <20210817100203.21300-1-sherry.sun@nxp.com> (raw)

From: Fugang Duan <fugang.duan@nxp.com>

There have a corner case that tx DMA .callback() is coming after
.flush_buffer(), then .callback() should check dma_tx_in_progress
flag and return in directly.

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
---
 drivers/tty/serial/fsl_lpuart.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 460e428b7592..117e011aff5f 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -479,6 +479,10 @@ static void lpuart_dma_tx_complete(void *arg)
 	unsigned long flags;
 
 	spin_lock_irqsave(&sport->port.lock, flags);
+	if (!sport->dma_tx_in_progress) {
+		spin_unlock_irqrestore(&sport->port.lock, flags);
+		return;
+	}
 
 	dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
 		     DMA_TO_DEVICE);
-- 
2.17.1


                 reply	other threads:[~2021-08-17 10:04 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210817100203.21300-1-sherry.sun@nxp.com \
    --to=sherry.sun@nxp.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=jirislaby@kernel.org \
    --cc=linux-imx@nxp.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-serial@vger.kernel.org \
    --subject='Re: [PATCH] tty: serial: fsl_lpuart: check dma_tx_in_progress in tx dma callback' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).