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 6064DC433F5 for ; Thu, 5 May 2022 22:34:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1384641AbiEEWiI (ORCPT ); Thu, 5 May 2022 18:38:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1379812AbiEEWiE (ORCPT ); Thu, 5 May 2022 18:38:04 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E76A5F25E for ; Thu, 5 May 2022 15:34:20 -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 ams.source.kernel.org (Postfix) with ESMTPS id F08CBB830E9 for ; Thu, 5 May 2022 22:34:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A1A82C385A8; Thu, 5 May 2022 22:34:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1651790057; bh=RV/T1QDyrTmWfR84H6v00PamvPTZNJRt/x3LYKhdXLk=; h=Subject:To:From:Date:From; b=2o0h3FEihjt4i6fkF6Oa+N1xqlKZbHj47qpkrfrk/yGjgMkElSICU/wlTb0cZWDqv Bm0E8jNTXsL7eXJ5DoGQZ2iej8qzsspIQDV3/g+lVZMxYZ/5hpwvdlll06A4U9tcpB WoZTMR3vwI0O/zjA5tI+Oq9p1OyHTROveS6aOlNM= Subject: patch "serial: pch: don't overwrite xmit->buf[0] by x_char" added to tty-testing To: jslaby@suse.cz, gregkh@linuxfoundation.org, stable@vger.kernel.org From: Date: Thu, 05 May 2022 22:43:02 +0200 Message-ID: <165178338214670@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled serial: pch: don't overwrite xmit->buf[0] by x_char to my tty git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git in the tty-testing branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will be merged to the tty-next branch sometime soon, after it passes testing, and the merge window is open. If you have any questions about this process, please let me know. >From d9f3af4fbb1d955bbaf872d9e76502f6e3e803cb Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Tue, 3 May 2022 10:08:03 +0200 Subject: serial: pch: don't overwrite xmit->buf[0] by x_char When x_char is to be sent, the TX path overwrites whatever is in the circular buffer at offset 0 with x_char and sends it using pch_uart_hal_write(). I don't understand how this was supposed to work if xmit->buf[0] already contained some character. It must have been lost. Remove this whole pop_tx_x() concept and do the work directly in the callers. (Without printing anything using dev_dbg().) Cc: Fixes: 3c6a483275f4 (Serial: EG20T: add PCH_UART driver) Signed-off-by: Jiri Slaby Link: https://lore.kernel.org/r/20220503080808.28332-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/pch_uart.c | 27 +++++++-------------------- 1 file changed, 7 insertions(+), 20 deletions(-) diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c index f872613a5e83..6cb631487383 100644 --- a/drivers/tty/serial/pch_uart.c +++ b/drivers/tty/serial/pch_uart.c @@ -624,22 +624,6 @@ static int push_rx(struct eg20t_port *priv, const unsigned char *buf, return 0; } -static int pop_tx_x(struct eg20t_port *priv, unsigned char *buf) -{ - int ret = 0; - struct uart_port *port = &priv->port; - - if (port->x_char) { - dev_dbg(priv->port.dev, "%s:X character send %02x (%lu)\n", - __func__, port->x_char, jiffies); - buf[0] = port->x_char; - port->x_char = 0; - ret = 1; - } - - return ret; -} - static int dma_push_rx(struct eg20t_port *priv, int size) { int room; @@ -889,9 +873,10 @@ static unsigned int handle_tx(struct eg20t_port *priv) fifo_size = max(priv->fifo_size, 1); tx_empty = 1; - if (pop_tx_x(priv, xmit->buf)) { - pch_uart_hal_write(priv, xmit->buf, 1); + if (port->x_char) { + pch_uart_hal_write(priv, &port->x_char, 1); port->icount.tx++; + port->x_char = 0; tx_empty = 0; fifo_size--; } @@ -948,9 +933,11 @@ static unsigned int dma_handle_tx(struct eg20t_port *priv) } fifo_size = max(priv->fifo_size, 1); - if (pop_tx_x(priv, xmit->buf)) { - pch_uart_hal_write(priv, xmit->buf, 1); + + if (port->x_char) { + pch_uart_hal_write(priv, &port->x_char, 1); port->icount.tx++; + port->x_char = 0; fifo_size--; } -- 2.36.0