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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 5BFD4C43A1D for ; Thu, 12 Jul 2018 14:59:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ED0DF20843 for ; Thu, 12 Jul 2018 14:59:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ED0DF20843 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732673AbeGLPJR (ORCPT ); Thu, 12 Jul 2018 11:09:17 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:50676 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732373AbeGLPJR (ORCPT ); Thu, 12 Jul 2018 11:09:17 -0400 Received: from localhost (LFbn-1-12247-202.w90-92.abo.wanadoo.fr [90.92.61.202]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id D365BD4F; Thu, 12 Jul 2018 14:59:20 +0000 (UTC) Date: Thu, 12 Jul 2018 16:59:18 +0200 From: Greg KH To: Ludovic Desroches Cc: linux-serial@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, jslaby@suse.com, arnd@arndb.de, richard.genoud@gmail.com, nicolas.ferre@microchip.com, alexandre.belloni@bootlin.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] tty/serial: atmel: manage shutdown in case of RS485 or ISO7816 mode Message-ID: <20180712145918.GC22502@kroah.com> References: <20180711131638.12622-1-ludovic.desroches@microchip.com> <20180711131638.12622-4-ludovic.desroches@microchip.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180711131638.12622-4-ludovic.desroches@microchip.com> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 11, 2018 at 03:16:38PM +0200, Ludovic Desroches wrote: > From: Nicolas Ferre > > In atmel_shutdown() we call atmel_stop_rx() and atmel_stop_tx() functions. > Prevent the rx restart that is implemented in RS485 or ISO7816 modes when > calling atmel_stop_tx() by using the atomic information tasklet_shutdown > that is already in place for this purpose. > > Signed-off-by: Nicolas Ferre No signed-off-by from you? > --- > drivers/tty/serial/atmel_serial.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c > index 0118b219f3a8..e4f877e1f3c6 100644 > --- a/drivers/tty/serial/atmel_serial.c > +++ b/drivers/tty/serial/atmel_serial.c > @@ -617,7 +617,9 @@ static void atmel_stop_tx(struct uart_port *port) > if (((port->rs485.flags & SER_RS485_ENABLED) && > !(port->rs485.flags & SER_RS485_RX_DURING_TX)) || > port->iso7816.flags & SER_ISO7816_ENABLED) > - atmel_start_rx(port); > + if (!atomic_read(&atmel_port->tasklet_shutdown)) > + atmel_start_rx(port); Is this really ok? No locking needed? What happens if that value is set right after this? thanks, greg k-h