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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 0E80EC28CBC for ; Wed, 6 May 2020 09:36:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D5EBC20838 for ; Wed, 6 May 2020 09:36:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="CKfE5oT2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728941AbgEFJgU (ORCPT ); Wed, 6 May 2020 05:36:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60576 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728640AbgEFJgU (ORCPT ); Wed, 6 May 2020 05:36:20 -0400 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D4175C061A0F for ; Wed, 6 May 2020 02:36:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:Content-Type:MIME-Version: Message-ID:Subject:To:From:Date:Reply-To:Cc:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=hqG1WbafwY2wTH670zLHTtxu7zyVtajux2PLVrtI/10=; b=CKfE5oT2vqWEKYdRCiY6PIUOA FWl8IEvOlgCVyxGNb/+cEVyhKbl3hdc0TVzopvwdvTezbILPRYHGlZfGQcfJ7fNYV6Z5xSJ/F/ogh uosVxfQ+Kjnibz1/6sPDGty0UToSKDeBoeldJE1G8Enfs/XJBD6ad8Entj3OOpx7FuEwzCk+pxW1a kzypJbwgrTa35Pj3/emtmLeeo85EYn3k0COAjx4wuyBArWHfdX2F8dbT2JI7Co513B/CMTOP6O9QC azNhgIcnFYvf84RcW4aKMmL8s2QMpQ3hm1zknL3yScQRAA3RVLf201LdEBMnuBGyYeRuRiVZMZsgZ Xg4c+y7Qg==; Received: from shell.armlinux.org.uk ([2002:4e20:1eda:1:5054:ff:fe00:4ec]:54410) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jWGTQ-0007nV-CU for linux-i2c@vger.kernel.org; Wed, 06 May 2020 10:36:16 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1jWGTP-00083f-M1; Wed, 06 May 2020 10:36:15 +0100 Date: Wed, 6 May 2020 10:36:15 +0100 From: Russell King - ARM Linux admin To: linux-i2c@vger.kernel.org Subject: [PATCH 0/2] Use master-abort for slave probes Message-ID: <20200506093615.GO1551@shell.armlinux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Hi, This series allows us to use the "master abort" feature when probing slaves rather than resetting the controller, which allows more graceful recovery to bus free state after sending the address byte. The i2c-pxa controller expects to send data after the address byte rather than a stop. Rather than resetting the bus (and thus forcing a bus-free state by releasing the SCL line) which may leave the bus in an indeterminant state, use the master-abort command instead. This patch series applies on top of the previous posted cleanup patches, although it may also apply to -rc. drivers/i2c/busses/i2c-pxa.c | 16 ++++------------ 1 file changed, 4 insertions(+), 12 deletions(-) -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 10.2Mbps down 587kbps up