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 X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 81CB8C4360F for ; Wed, 3 Apr 2019 14:02:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 514AC2148E for ; Wed, 3 Apr 2019 14:02:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554300163; bh=ovvFaVz/VNKNzFNVRKM+6+yAcjw8ST9hGcFAI0FvyPg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=2eyXvF+KxAe1UYcKmBLBKoN9H8N60amxBAdXKA+TzLOPKkrHX8VrI1FEIN/pg0v32 WbBwxMQ2qonQN8qa2P1fU1DPDfPuVLfWsKIHKzmNoJ1E5LaHsSBWcnjk/jdxi+xawV e1d5xBvfPU80HErq5VlHfZDAxFUKKPeL1cuDa1hw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726199AbfDCOCm (ORCPT ); Wed, 3 Apr 2019 10:02:42 -0400 Received: from mail.kernel.org ([198.145.29.99]:59240 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726193AbfDCOCm (ORCPT ); Wed, 3 Apr 2019 10:02:42 -0400 Received: from localhost (217-101-180-136.cable.dynamic.v4.ziggo.nl [217.101.180.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7FE8A2075E; Wed, 3 Apr 2019 14:02:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554300162; bh=ovvFaVz/VNKNzFNVRKM+6+yAcjw8ST9hGcFAI0FvyPg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=BYTaD4CAAmRLLx6/qVFNv8kPhg26jiXSWUlG/usVLDp3cM+WJcgz9R7EcbmfTXOI6 Gl/QqXfDtsOaOgaOJeTaAp3vQ6T7F0PyR9a5oVqAd2zhqWLaS+ECYcul06SiLbRkOG ixgg/r0UqtFz1cc6NmlelHGY45qfdZEBWwKw3M6o= Date: Wed, 3 Apr 2019 16:02:39 +0200 From: Greg Kroah-Hartman To: Razvan Stefanescu Cc: stable@vger.kernel.org, Nicolas Ferre Subject: Re: [PATCH for-4.19 2/2] tty/serial: atmel: RS485 HD w/DMA: enable RX after TX is stopped Message-ID: <20190403140239.GC8633@kroah.com> References: <20190402095250.11334-1-razvan.stefanescu@microchip.com> <20190402095250.11334-2-razvan.stefanescu@microchip.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190402095250.11334-2-razvan.stefanescu@microchip.com> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Tue, Apr 02, 2019 at 12:52:50PM +0300, Razvan Stefanescu wrote: > commit 69646d7a3689 ("tty/serial: atmel: RS485 HD w/DMA: enable RX after TX is stopped") upstream. > > In half-duplex operation, RX should be started after TX completes. > > If DMA is used, there is a case when the DMA transfer completes but the > TX FIFO is not emptied, so the RX cannot be restarted just yet. > > Use a boolean variable to store this state and rearm TX interrupt mask > to be signaled again that the transfer finished. In interrupt transmit > handler this variable is used to start RX. A warning message is generated > if RX is activated before TX fifo is cleared. > > Fixes: b389f173aaa1 ("tty/serial: atmel: RS485 half duplex w/DMA: enable > RX after TX is done") > Signed-off-by: Razvan Stefanescu > Acked-by: Richard Genoud > Cc: stable > Signed-off-by: Greg Kroah-Hartman > --- > drivers/tty/serial/atmel_serial.c | 24 +++++++++++++++++++++--- > 1 file changed, 21 insertions(+), 3 deletions(-) > Happen to have a version of this for 4.4.y and 4.9.y? I've queued both of these patches up now, thanks. greg k-h