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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 83F61C63699 for ; Sun, 15 Nov 2020 08:45:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 53EFA22454 for ; Sun, 15 Nov 2020 08:45:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726678AbgKOIoV (ORCPT ); Sun, 15 Nov 2020 03:44:21 -0500 Received: from muru.com ([72.249.23.125]:48306 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726647AbgKOInc (ORCPT ); Sun, 15 Nov 2020 03:43:32 -0500 Received: from atomide.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id 1C11780A0; Sun, 15 Nov 2020 08:43:17 +0000 (UTC) Date: Sun, 15 Nov 2020 10:43:08 +0200 From: Tony Lindgren To: Tim Harvey Cc: Lee Jones , open list , Carl Philipp Klemm , Laxminath Kasam , Merlijn Wajer , Mark Brown , Pavel Machek , Sebastian Reichel Subject: Re: [PATCH] mfd: cpcap: Fix interrupt regression with regmap clear_ack Message-ID: <20201115084308.GY26857@atomide.com> References: <20201111170613.46057-1-tony@atomide.com> <20201113102134.GI3718728@dell> 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-kernel@vger.kernel.org * Tim Harvey [201113 22:07]: > 3a6f0fb7b8eb ("regmap: irq: Add support to clear ack registers") > appears to not only add the new clear_ack case it also attempts to > resolve the long standing ack_invert issue with this change: > > - ret = regmap_write(map, reg, data->status_buf[i]); > + if (chip->ack_invert) > + ret = regmap_write(map, reg, > + ~data->status_buf[i]); > + else > + ret = regmap_write(map, reg, > + data->status_buf[i]); Yes that's what I noticed too. And that's why cpcap was working for me with ack_invert and without it earlier. > However, this still doesn't resolve the issue I have with my > device/driver because it ends up writing 1's to all the other bits in > the ack register which keeps my device's interrupt from de-asserting. > Perhaps that's a strange behavior of my device that it allows you to > 'set' interrupt source bits which causes the interrupt to stay > asserted? I'm also wondering if my issue is that I currently have the > interrupt registered as such: > > ret = devm_regmap_add_irq_chip(dev, gsc->regmap, client->irq, > IRQF_ONESHOT | IRQF_SHARED | IRQF_TRIGGER_FALLING, 0, &gsc_irq_chip, > &irq_data); > > Perhaps this should be IRQF_TRIGGER_LOW as the device will not > de-assert its IRQ# until all source bits are cleared. Yes could be. For cpcap, we have IRQ_TYPE_LEVEL_HIGH configured in the motorola-cpcap-mapphone.dtsi file. > Tony, I thought that your pcap issue was that it truly did not have an > inverted ack and the fact that ack_invert did not work was why you > never noticed any issue. If this is true I would think you would want > to disable ack_invert but not necessarily enable clear_ack. Did your > testing show it needed to toggle the ack to clear it? Well I looked at the v3.0.8 Motorola Linux Android kernel, it actually does clear_ack. So I'd rather keep the same logic as we have no proper documentation for cpcap. I also confirmed still works without ack_invert too while ack_invert now is broken. But using clear_ack now that we have it working seems safer. Regards, Tony