From patchwork Wed May 4 16:43:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 569873 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 559CAC433F5 for ; Wed, 4 May 2022 16:54:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354206AbiEDQ6Z (ORCPT ); Wed, 4 May 2022 12:58:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52440 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354074AbiEDQ5O (ORCPT ); Wed, 4 May 2022 12:57:14 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D38149FA9; Wed, 4 May 2022 09:50:01 -0700 (PDT) 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 dfw.source.kernel.org (Postfix) with ESMTPS id D89546174C; Wed, 4 May 2022 16:50:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 31740C385A4; Wed, 4 May 2022 16:50:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1651683000; bh=x7xIzJvo8hUwDLxm/wNRMDrcSJap708f1jPagQ0MR4I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hqJ1ntUxvk3VMYjhF1Ymb13QAoVjZr20j8GSOEBMAZT4xheqnNd40cFghLMh6U2G9 nlspqSOP4QYUaFTQeOcDBRZcgGNVPYqq7RB2wcKGMyF+zvt5oZZ8YSZLz0ccuqXm3u 0NPmxaj49Xay0pgdxfvvvTh2hQ4KWX9TbEoczUBQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Maciej W. Rozycki" , Andy Shevchenko Subject: [PATCH 5.10 029/129] serial: 8250: Also set sticky MCR bits in console restoration Date: Wed, 4 May 2022 18:43:41 +0200 Message-Id: <20220504153023.590688263@linuxfoundation.org> X-Mailer: git-send-email 2.36.0 In-Reply-To: <20220504153021.299025455@linuxfoundation.org> References: <20220504153021.299025455@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Maciej W. Rozycki commit 6e6eebdf5e2455f089ccd000754a0deaeb79af82 upstream. Sticky MCR bits are lost in console restoration if console suspending has been disabled. This currently affects the AFE bit, which works in combination with RTS which we set, so we want to make sure the UART retains control of its FIFO where previously requested. Also specific drivers may need other bits in the future. Signed-off-by: Maciej W. Rozycki Fixes: 4516d50aabed ("serial: 8250: Use canary to restart console after suspend") Cc: stable@vger.kernel.org # v4.0+ Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181518490.9383@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_port.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -3311,7 +3311,7 @@ static void serial8250_console_restore(s serial8250_set_divisor(port, baud, quot, frac); serial_port_out(port, UART_LCR, up->lcr); - serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS); + serial8250_out_MCR(up, up->mcr | UART_MCR_DTR | UART_MCR_RTS); } /*