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 4E85DC433EF for ; Thu, 14 Jul 2022 15:56:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239411AbiGNP4j (ORCPT ); Thu, 14 Jul 2022 11:56:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57542 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240022AbiGNP4g (ORCPT ); Thu, 14 Jul 2022 11:56:36 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E61B8491C4 for ; Thu, 14 Jul 2022 08:56:35 -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 983B6B8272B for ; Thu, 14 Jul 2022 15:56:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C8D0CC34114; Thu, 14 Jul 2022 15:56:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1657814193; bh=PJFNyZBFKDLq33IWYE/QhjrUyUhV0/nbYTzlILvgK1Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nTHNHSJq16w4Jg341ogjqBmfqlpYshvG5hrqa75jENUq8GvOnMaYQb5EHfW5XH37X mEwqivMA44myF8tbyt+eS3aHp2hWo46e6r93kJzEeWcnQgYIqXP5HuNq2eHX4FzYCb AWrOkmao8pR6WFNcDb01TgRen4hmpFdazGoNyMdg= Date: Thu, 14 Jul 2022 17:56:30 +0200 From: Greg KH To: Shenwei Wang Cc: "linux-serial@vger.kernel.org" Subject: Re: [EXT] Re: [PATCH V1 1/1] serial: fsl_lpuart: zero out parity bit in CS7 mode Message-ID: References: <20220708195800.325933-1-shenwei.wang@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On Thu, Jul 14, 2022 at 03:50:24PM +0000, Shenwei Wang wrote: > > > > -----Original Message----- > > From: Greg KH > > Sent: Thursday, July 14, 2022 10:31 AM > > To: Shenwei Wang > > Cc: linux-serial@vger.kernel.org > > Subject: Re: [EXT] Re: [PATCH V1 1/1] serial: fsl_lpuart: zero out parity bit in CS7 > > mode > > > > Caution: EXT Email > > > > On Thu, Jul 14, 2022 at 03:26:30PM +0000, Shenwei Wang wrote: > > > > > > > > > > -----Original Message----- > > > > From: Greg KH > > > > Sent: Thursday, July 14, 2022 10:24 AM > > > > To: Shenwei Wang > > > > Cc: linux-serial@vger.kernel.org > > > > Subject: Re: [EXT] Re: [PATCH V1 1/1] serial: fsl_lpuart: zero out > > > > parity bit in CS7 mode > > > > > > > > Caution: EXT Email > > > > > > > > On Thu, Jul 14, 2022 at 03:11:35PM +0000, Shenwei Wang wrote: > > > > > > > > > > > > > > > > -----Original Message----- > > > > > > From: Greg KH > > > > > > Sent: Thursday, July 14, 2022 9:31 AM > > > > > > To: Shenwei Wang > > > > > > Cc: linux-serial@vger.kernel.org > > > > > > Subject: [EXT] Re: [PATCH V1 1/1] serial: fsl_lpuart: zero out > > > > > > parity bit in CS7 mode > > > > > > > > > > > > Caution: EXT Email > > > > > > > > > > > > On Fri, Jul 08, 2022 at 02:58:00PM -0500, shenwei.wang@nxp.com wrote: > > > > > > > The LPUART hardware doesn't zero out the parity bit on the > > > > > > > received characters. This behavior won't impact the use cases > > > > > > > of > > > > > > > CS8 because the parity bit is the 9th bit which is not > > > > > > > currently used by > > > > software. > > > > > > > But the parity bit for CS7 must be zeroed out by software in > > > > > > > order to get the correct raw data. > > > > > > > > > > > > > > Signed-off-by: Shenwei Wang > > > > > > > > > > > > What commit id does this fix? > > > > > > > > > > The issue should have been there since the driver was written. As > > > > > the CS7 > > > > mode was rarely used, we didn't notice the problem in the driver before. > > > > > > > > So should this be backported to older stable kernels? > > > > > > > > > > Yes, that would be great. > > > > Great, properly label it as such when you resend this. > > This is my first time to handle this kind of label. Can you let me know how to label it for older stable kernels? Please read: https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html It should explain it fully, if not, please let me know. thanks, greg k-h