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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 044E3C04AAF for ; Tue, 21 May 2019 08:33:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CE91B216B7 for ; Tue, 21 May 2019 08:33:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726753AbfEUIdw (ORCPT ); Tue, 21 May 2019 04:33:52 -0400 Received: from mx2.suse.de ([195.135.220.15]:56274 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726006AbfEUIdv (ORCPT ); Tue, 21 May 2019 04:33:51 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 7017BAB9D; Tue, 21 May 2019 08:33:50 +0000 (UTC) From: Andreas Schwab To: Sagar Shrikant Kadam Cc: robh+dt@kernel.org, mark.rutland@arm.com, peter@korsgaard.com, andrew@lunn.ch, palmer@sifive.com, paul.walmsley@sifive.com, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 3/3] i2c-ocores: sifive: add polling mode workaround for FU540-C000 SoC. References: <1558361478-4381-1-git-send-email-sagar.kadam@sifive.com> <1558361478-4381-4-git-send-email-sagar.kadam@sifive.com> X-Yow: I can see you GUYS an' GALS need a LOT of HELP...You're all very STUPID!! I used to be STUPID, too..before I started watching UHF-TV!! Date: Tue, 21 May 2019 10:33:48 +0200 In-Reply-To: <1558361478-4381-4-git-send-email-sagar.kadam@sifive.com> (Sagar Shrikant Kadam's message of "Mon, 20 May 2019 19:41:18 +0530") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mai 20 2019, Sagar Shrikant Kadam wrote: > The i2c-ocore driver already has a polling mode interface.But it needs > a workaround for FU540 Chipset on HiFive unleashed board (RevA00). > There is an erratum in FU540 chip that prevents interrupt driven i2c > transfers from working, and also the I2C controller's interrupt bit > cannot be cleared if set, due to this the existing i2c polling mode > interface added in mainline earlier doesn't work, and CPU stall's > infinitely, when-ever i2c transfer is initiated. > > Ref:previous polling mode support in mainline > > commit 69c8c0c0efa8 ("i2c: ocores: add polling interface") > > The workaround / fix under OCORES_FLAG_BROKEN_IRQ is particularly for > FU540-COOO SoC. After commit dd7dbf0eb090 this no longer fits. Andreas. -- Andreas Schwab, SUSE Labs, schwab@suse.de GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 "And now for something completely different."