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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4294FC6FA82 for ; Wed, 14 Sep 2022 16:03:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230363AbiINQDl (ORCPT ); Wed, 14 Sep 2022 12:03:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33558 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229987AbiINQDc (ORCPT ); Wed, 14 Sep 2022 12:03:32 -0400 Received: from mx0b-001ae601.pphosted.com (mx0a-001ae601.pphosted.com [67.231.149.25]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8C6647645D for ; Wed, 14 Sep 2022 09:03:31 -0700 (PDT) Received: from pps.filterd (m0077473.ppops.net [127.0.0.1]) by mx0a-001ae601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 28EDg5el005918; Wed, 14 Sep 2022 11:02:58 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cirrus.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding : content-type; s=PODMain02222019; bh=hi6eNZvXbLgXiyHBsjnEgONqLlog+MqOa3l94OJaQOA=; b=RWtV7+fe+PX1zZQufLduUKgyAXLRNEyz/6Jq8eqHtAOD1MT6CAsmPdGXAOcENXLdk0Qi DkRTQRXYZDaXjZdTb5FemPiJTApm5mTL3s37qq8MYba3SYC10MiioVvHBikW8BOqxMdo urfkKE9QQJ8oVg9HCnDJVaTsqjZ8jJmgUadz8MY8rL2mweD4gjIysulOc1tDciANAwUb dpZxxLbBppn4eaVZ4ek05lCn2XlFCHmjy9gpgYNZC+T+gKGe2LfnpOGMDbJuwzCbIcJs rv6M4233dgSbebDLOkhMbdm3iibweuPmcTo4/AzMTw1fmip11HNUF9tBViaJ8bDy8jBG kg== Received: from ediex01.ad.cirrus.com ([84.19.233.68]) by mx0a-001ae601.pphosted.com (PPS) with ESMTPS id 3jjy05h8ek-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 14 Sep 2022 11:02:58 -0500 Received: from ediex01.ad.cirrus.com (198.61.84.80) by ediex01.ad.cirrus.com (198.61.84.80) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.12; Wed, 14 Sep 2022 11:02:55 -0500 Received: from ediswmail.ad.cirrus.com (198.61.86.93) by ediex01.ad.cirrus.com (198.61.84.80) with Microsoft SMTP Server id 15.2.1118.12 via Frontend Transport; Wed, 14 Sep 2022 11:02:55 -0500 Received: from edi-sw-dsktp-006.ad.cirrus.com (edi-sw-dsktp-006.ad.cirrus.com [198.90.251.95]) by ediswmail.ad.cirrus.com (Postfix) with ESMTP id 05E10468; Wed, 14 Sep 2022 16:02:49 +0000 (UTC) From: Richard Fitzgerald To: , , , CC: , , , Richard Fitzgerald Subject: [PATCH v4 0/5] soundwire: Fixes for spurious and missing UNATTACH Date: Wed, 14 Sep 2022 17:02:43 +0100 Message-ID: <20220914160248.1047627-1-rf@opensource.cirrus.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Proofpoint-GUID: Fg09cf9ubQfrVVWvJJ-ffLdCZ0X1H6fK X-Proofpoint-ORIG-GUID: Fg09cf9ubQfrVVWvJJ-ffLdCZ0X1H6fK X-Proofpoint-Spam-Reason: safe Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The bus and cadence code has several bugs that cause UNATTACH notifications to either be sent spuriously or to be missed. These can be seen occasionally with a single peripheral on the bus, but are much more frequent with multiple peripherals, where several peripherals could change state and report in consecutive PINGs. The root of all of these bugs seems to be a code design flaw that assumed every PING status change would be handled separately. However, PINGs are handled by a workqueue function and there is no guarantee when that function will be scheduled to run or how much CPU time it will receive. PINGs will continue while the work function is handling a snapshot of a previous PING so the code must take account that (a) status could change during the work function and (b) there can be a backlog of changes before the IRQ work function runs again. Tested with 4 peripherals on 1 bus, and 8 peripherals on 2 buses. CHANGES SINCE V3: Fixed minor comment typo in patch #4. Richard Fitzgerald (4): soundwire: bus: Don't lose unattach notifications soundwire: bus: Don't re-enumerate before status is UNATTACHED soundwire: cadence: Fix lost ATTACHED interrupts when enumerating soundwire: bus: Don't exit early if no device IDs were programmed Simon Trimmer (1): soundwire: cadence: fix updating slave status when a bus has multiple peripherals drivers/soundwire/bus.c | 44 +++++++++++++--- drivers/soundwire/cadence_master.c | 80 ++++++++++++++++-------------- 2 files changed, 80 insertions(+), 44 deletions(-) -- 2.30.2