From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9D534C46467 for ; Mon, 16 Jan 2023 16:35:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233450AbjAPQf0 (ORCPT ); Mon, 16 Jan 2023 11:35:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48354 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233201AbjAPQee (ORCPT ); Mon, 16 Jan 2023 11:34:34 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E4DB222F9 for ; Mon, 16 Jan 2023 08:22:18 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id ED9ECB8105F for ; Mon, 16 Jan 2023 16:22:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4832EC433D2; Mon, 16 Jan 2023 16:22:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1673886135; bh=MBu6CtxMxILESpZ9aOISdMboZQllQPiDEDGb5CAHzkc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=chsq5XciY9NQ4s0oU48A8Sxzz28l+6WcLxHa5c+iJooxEuzHbpnHnuaLUuZ3d1Sc7 vqBqKGWXRbXKCMQMoGhnQNhD/ST410Kl572Y93jVQEpU6kZvpD6R9Fbq1YWU/E6wve a/Eq5g3uGumNVn4b7E4HP1FbhgFxgi9F/ZMvwRTg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, delisun , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , Sasha Levin Subject: [PATCH 5.4 286/658] serial: pl011: Do not clear RX FIFO & RX interrupt in unthrottle. Date: Mon, 16 Jan 2023 16:46:14 +0100 Message-Id: <20230116154922.674423349@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230116154909.645460653@linuxfoundation.org> References: <20230116154909.645460653@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: delisun [ Upstream commit 032d5a71ed378ffc6a2d41a187d8488a4f9fe415 ] Clearing the RX FIFO will cause data loss. Copy the pl011_enabl_interrupts implementation, and remove the clear interrupt and FIFO part of the code. Fixes: 211565b10099 ("serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottle") Signed-off-by: delisun Reviewed-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20221110020108.7700-1-delisun@pateo.com.cn Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/amba-pl011.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 44485689333e..86084090232d 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1771,8 +1771,17 @@ static void pl011_enable_interrupts(struct uart_amba_port *uap) static void pl011_unthrottle_rx(struct uart_port *port) { struct uart_amba_port *uap = container_of(port, struct uart_amba_port, port); + unsigned long flags; - pl011_enable_interrupts(uap); + spin_lock_irqsave(&uap->port.lock, flags); + + uap->im = UART011_RTIM; + if (!pl011_dma_rx_running(uap)) + uap->im |= UART011_RXIM; + + pl011_write(uap->im, uap, REG_IMSC); + + spin_unlock_irqrestore(&uap->port.lock, flags); } static int pl011_startup(struct uart_port *port) -- 2.35.1