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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 6EFEEC433E0 for ; Mon, 28 Dec 2020 15:14:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 421C522A84 for ; Mon, 28 Dec 2020 15:14:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2440675AbgL1PO2 (ORCPT ); Mon, 28 Dec 2020 10:14:28 -0500 Received: from mail.kernel.org ([198.145.29.99]:41002 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2438187AbgL1OGp (ORCPT ); Mon, 28 Dec 2020 09:06:45 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id B927E207B2; Mon, 28 Dec 2020 14:06:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609164389; bh=u5X+2vQlcDHXjag+vwKfk4kgAsp+c+mxOCHIScp1xc8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=A4uJKkR8SnRlNfz4tTFaifzXUrECVX4gFcNzd0Mnwb5hMu5rlDCNVjthZVr73rjCb TWRgpcY+6KFxH+On6YBvbuvzmMV81qeCyT1cA57RBRZe923zZOQv7Sk9tABPSki1UM pHMojFiYW5X7hr95NeR0l2JP4EfPCnoOEL5aSKqI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Carl Philipp Klemm , Laxminath Kasam , Merlijn Wajer , Mark Brown , Pavel Machek , Sebastian Reichel , Tim Harvey , Tony Lindgren , Lee Jones , Sasha Levin Subject: [PATCH 5.10 163/717] mfd: cpcap: Fix interrupt regression with regmap clear_ack Date: Mon, 28 Dec 2020 13:42:41 +0100 Message-Id: <20201228125028.766318260@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228125020.963311703@linuxfoundation.org> References: <20201228125020.963311703@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tony Lindgren [ Upstream commit 14639a22de657eabbb776f503a816594393cc935 ] With commit 3a6f0fb7b8eb ("regmap: irq: Add support to clear ack registers"), the cpcap interrupts are no longer getting acked properly leading to a very unresponsive device with CPUs fully loaded spinning in the threaded IRQ handlers. To me it looks like the clear_ack commit above actually fixed a long standing bug in regmap_irq_thread() where we unconditionally acked the interrupts earlier without considering ack_invert. And the issue with cpcap started happening as we now also consider ack_invert. Tim Harvey tried to fix this issue earlier with "[PATCH v2] regmap: irq: fix ack-invert", but the reading of the ack register was considered unnecessary for just ack_invert, and we did not have clear_ack available yet. As the cpcap irqs worked both with and without ack_invert earlier because of the unconditional ack, the problem remained hidden until now. Also, looks like the earlier v3.0.8 based Motorola Android Linux kernel does clear_ack style read-clear-write with "ireg_val & ~mreg_val" instead of just ack_invert style write. So let's switch cpcap to use clear_ack to fix the issue. Fixes: 3a6f0fb7b8eb ("regmap: irq: Add support to clear ack registers") Cc: Carl Philipp Klemm Cc: Laxminath Kasam Cc: Merlijn Wajer Cc: Mark Brown Cc: Pavel Machek Cc: Sebastian Reichel Cc: Tim Harvey Signed-off-by: Tony Lindgren Tested-by: Pavel Machek Reviewed-By: Tim Harvey Signed-off-by: Lee Jones Signed-off-by: Sasha Levin --- drivers/mfd/motorola-cpcap.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/mfd/motorola-cpcap.c b/drivers/mfd/motorola-cpcap.c index 2283d88adcc25..30d82bfe5b02f 100644 --- a/drivers/mfd/motorola-cpcap.c +++ b/drivers/mfd/motorola-cpcap.c @@ -97,7 +97,7 @@ static struct regmap_irq_chip cpcap_irq_chip[CPCAP_NR_IRQ_CHIPS] = { .ack_base = CPCAP_REG_MI1, .mask_base = CPCAP_REG_MIM1, .use_ack = true, - .ack_invert = true, + .clear_ack = true, }, { .name = "cpcap-m2", @@ -106,7 +106,7 @@ static struct regmap_irq_chip cpcap_irq_chip[CPCAP_NR_IRQ_CHIPS] = { .ack_base = CPCAP_REG_MI2, .mask_base = CPCAP_REG_MIM2, .use_ack = true, - .ack_invert = true, + .clear_ack = true, }, { .name = "cpcap1-4", @@ -115,7 +115,7 @@ static struct regmap_irq_chip cpcap_irq_chip[CPCAP_NR_IRQ_CHIPS] = { .ack_base = CPCAP_REG_INT1, .mask_base = CPCAP_REG_INTM1, .use_ack = true, - .ack_invert = true, + .clear_ack = true, }, }; -- 2.27.0