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=-6.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no 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 7DE0DC43461 for ; Mon, 14 Sep 2020 10:42:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2AC142076C for ; Mon, 14 Sep 2020 10:42:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=dh-electronics.com header.i=@dh-electronics.com header.b="tkjqpb1o" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726453AbgINKlx (ORCPT ); Mon, 14 Sep 2020 06:41:53 -0400 Received: from mx2.securetransport.de ([188.68.39.254]:47616 "EHLO mx2.securetransport.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726449AbgINKka (ORCPT ); Mon, 14 Sep 2020 06:40:30 -0400 X-Greylist: delayed 384 seconds by postgrey-1.27 at vger.kernel.org; Mon, 14 Sep 2020 06:40:26 EDT Received: from mail.dh-electronics.com (business-24-134-97-169.pool2.vodafone-ip.de [24.134.97.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx2.securetransport.de (Postfix) with ESMTPSA id 4025B5E879; Mon, 14 Sep 2020 12:33:17 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dh-electronics.com; s=dhelectronicscom; t=1600079597; bh=QqiALWQWqzk3v5Egngf7/oNah0zdhttVToTd3Q1YPvQ=; h=From:To:CC:Subject:Date:In-Reply-To:References:From; b=tkjqpb1o8Of4A2fKxnLJoTJGfj3Sgr2FaVttqYfn6gwrqcAPlozgl5MpScJ/8J7vb +F7vh1Z/4Il6S6ICqH668xixkwxizgft4T0+gSpEITbuEROGQiU/OVmSrGh4CX1Msm 9Twyh5t3llDHa3qPPhy+Doy49mMQ+1TU82yDjNz+uFmAzB/ZUPXs2zaaLjUYn0kIID BLbQDu3+iXvqwd+7hBQINr5Agq35uSPcJWt1VqkeB0r66OMlUsDVUomW1UhmeXDU4u 7usFuA7bMc7yy7Imb/9Ne2T4JGI69wb1suEW9Un+ec3f5fbFkiwzDElqHKVJclP0R0 O3NI5qCowHLqA== Received: from DHPWEX01.DH-ELECTRONICS.ORG (2001:470:76a7:2::30) by DHPWEX01.DH-ELECTRONICS.ORG (2001:470:76a7:2::30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.659.4; Mon, 14 Sep 2020 12:33:10 +0200 Received: from deb10-lzenz.dh-electronics.org (10.64.6.180) by DHPWEX01.DH-ELECTRONICS.ORG (10.64.2.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.659.4 via Frontend Transport; Mon, 14 Sep 2020 12:33:10 +0200 From: Ludwig Zenz To: CC: , , , , , , , , , Subject: [PATCH v2 2/5] spi: stm32: fix fifo threshold level in case of short transfer Date: Mon, 14 Sep 2020 12:33:00 +0200 Message-ID: <20200914103300.5832-1-lzenz@dh-electronics.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <1597043558-29668-3-git-send-email-alain.volmat@st.com> References: <1597043558-29668-3-git-send-email-alain.volmat@st.com> MIME-Version: 1.0 X-klartext: yes Content-Transfer-Encoding: 8bit Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > When transfer is shorter than half of the fifo, set the data packet size > up to transfer size instead of up to half of the fifo. > Check also that threshold is set at least to 1 data frame. Through a git-bisect we have identified this patch as problematic. We have an application that uses a SPI protocol with telegrams of length 2 to 16 bytes. Due to this patch we have errors in the data transfer of the MOSI direction. We use SPI in PIO mode. Please explain what this patch should improve or what exactly is changed in the behaviour. best regards, Ludwig Zenz