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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 7764AC04E30 for ; Mon, 9 Dec 2019 23:55:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4F7B020726 for ; Mon, 9 Dec 2019 23:55:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727639AbfLIXzt (ORCPT ); Mon, 9 Dec 2019 18:55:49 -0500 Received: from mga02.intel.com ([134.134.136.20]:13468 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727625AbfLIXzq (ORCPT ); Mon, 9 Dec 2019 18:55:46 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 09 Dec 2019 15:55:46 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,297,1571727600"; d="scan'208";a="210273693" Received: from bbower-mobl.amr.corp.intel.com (HELO pbossart-mobl3.amr.corp.intel.com) ([10.254.65.172]) by fmsmga008.fm.intel.com with ESMTP; 09 Dec 2019 15:55:44 -0800 From: Pierre-Louis Bossart To: alsa-devel@alsa-project.org Cc: linux-kernel@vger.kernel.org, tiwai@suse.de, broonie@kernel.org, vkoul@kernel.org, gregkh@linuxfoundation.org, jank@cadence.com, srinivas.kandagatla@linaro.org, slawomir.blauciak@intel.com, Bard liao , Rander Wang , Ranjani Sridharan , Pierre-Louis Bossart , Sanyog Kale Subject: [PATCH v4 10/11] soundwire: intel: add mutex for shared SHIM register access Date: Mon, 9 Dec 2019 17:55:18 -0600 Message-Id: <20191209235520.18727-11-pierre-louis.bossart@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191209235520.18727-1-pierre-louis.bossart@linux.intel.com> References: <20191209235520.18727-1-pierre-louis.bossart@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some of the Intel SoundWire SHIM registers contain fields for different links. Without protection, the master drivers for the different links will access these shared registers, leading to invalid configurations and timeouts (specifically when changing CPA/SPA power-related registers and polling for the changes to be applied). A mutex is added to make sure all rmw access to those registers are serialized. Signed-off-by: Pierre-Louis Bossart --- include/linux/soundwire/sdw_intel.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/linux/soundwire/sdw_intel.h b/include/linux/soundwire/sdw_intel.h index f9937072dc53..4336bc8e3d83 100644 --- a/include/linux/soundwire/sdw_intel.h +++ b/include/linux/soundwire/sdw_intel.h @@ -69,6 +69,7 @@ struct sdw_intel_link_res; * @links: information for each link (controller-specific and kept * opaque here) * @link_list: list to handle interrupts across all links + * @shim_lock: mutex to handle concurrent rmw access to shared SHIM registers. */ struct sdw_intel_ctx { int count; @@ -77,6 +78,7 @@ struct sdw_intel_ctx { acpi_handle handle; struct sdw_intel_link_res *links; struct list_head link_list; + struct mutex shim_lock; /* lock for access to shared SHIM registers */ }; /** -- 2.20.1