From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Authentication-Results: smtp.codeaurora.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=micronovasrl.com header.i=@micronovasrl.com header.b="RwZg/WS0" DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 38BF160263 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=micronovasrl.com Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932535AbeFFJuL (ORCPT + 25 others); Wed, 6 Jun 2018 05:50:11 -0400 Received: from mail.micronovasrl.com ([212.103.203.10]:55582 "EHLO mail.micronovasrl.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932378AbeFFJuH (ORCPT ); Wed, 6 Jun 2018 05:50:07 -0400 Authentication-Results: mail.micronovasrl.com (amavisd-new); dkim=pass reason="pass (just generated, assumed good)" header.d=micronovasrl.com From: Giulio Benetti Cc: matwey.kornilov@gmail.com, Giulio Benetti , Greg Kroah-Hartman , Jiri Slaby , Andy Shevchenko , Matthias Brugger , Kees Cook , Sean Young , Aaron Sierra , Tomas Melin , Sean Wang , Rafael Gago , Joel Stanley , linux-serial@vger.kernel.org (open list:SERIAL DRIVERS), linux-kernel@vger.kernel.org (open list) Subject: [PATCH 3/4] serial: 8250: Make em485_rts_after_send() set mctrl according to rts state. Date: Wed, 6 Jun 2018 11:49:38 +0200 Message-Id: <20180606094942.71190-2-giulio.benetti@micronovasrl.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180606094942.71190-1-giulio.benetti@micronovasrl.com> References: <20180606094942.71190-1-giulio.benetti@micronovasrl.com> To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When rs485 enabled and RTS_AFTER_SEND set on startup, need to preserve mctrl status, because later functions will call set_mctrl passing port->mctrl=0 overriding rts status, resulting in rts pin in transmission when idle. Make mctrl reflect rts pin state. Signed-off-by: Giulio Benetti --- drivers/tty/serial/8250/8250_port.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 95833cbc4338..c8c10b5ec6d6 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -562,10 +562,13 @@ static inline void serial8250_em485_rts_after_send(struct uart_8250_port *p) { unsigned char mcr = serial8250_in_MCR(p); - if (p->port.rs485.flags & SER_RS485_RTS_AFTER_SEND) + if (p->port.rs485.flags & SER_RS485_RTS_AFTER_SEND) { mcr |= UART_MCR_RTS; - else + p->port.mctrl |= TIOCM_RTS; + } else { mcr &= ~UART_MCR_RTS; + p->port.mctrl &= ~TIOCM_RTS; + } serial8250_out_MCR(p, mcr); } -- 2.17.1