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=-11.2 required=3.0 tests=BAYES_00,DATE_IN_PAST_06_12, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 5E4A7C433E4 for ; Tue, 18 Aug 2020 03:24:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43F0120716 for ; Tue, 18 Aug 2020 03:24:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726876AbgHRDYC (ORCPT ); Mon, 17 Aug 2020 23:24:02 -0400 Received: from mga03.intel.com ([134.134.136.65]:63987 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726863AbgHRDX7 (ORCPT ); Mon, 17 Aug 2020 23:23:59 -0400 IronPort-SDR: Sir+AYbbubVjGpS4RV+Sp5BxcPPzgs26QgbQJTAwPnSO+izn7Dq2ttmHg8TX9mVj60IfOc0P8U S8YuRwWksU9A== X-IronPort-AV: E=McAfee;i="6000,8403,9716"; a="154806530" X-IronPort-AV: E=Sophos;i="5.76,325,1592895600"; d="scan'208";a="154806530" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Aug 2020 20:23:59 -0700 IronPort-SDR: /0Oiq2v7oEO84PBx8dCyDdQi/1XbxcWWPi6v556zk6rS9vG1ZN1eleiwG363IJlo5D8HsdMVSm gXzHDtA98TLw== X-IronPort-AV: E=Sophos;i="5.76,325,1592895600"; d="scan'208";a="441084704" Received: from bard-ubuntu.sh.intel.com ([10.239.13.33]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Aug 2020 20:23:55 -0700 From: Bard Liao To: alsa-devel@alsa-project.org, vkoul@kernel.org Cc: vinod.koul@linaro.org, linux-kernel@vger.kernel.org, tiwai@suse.de, broonie@kernel.org, gregkh@linuxfoundation.org, jank@cadence.com, srinivas.kandagatla@linaro.org, rander.wang@linux.intel.com, ranjani.sridharan@linux.intel.com, hui.wang@canonical.com, pierre-louis.bossart@linux.intel.com, sanyog.r.kale@intel.com, mengdong.lin@intel.com, bard.liao@intel.com Subject: [PATCH v2 12/12] soundwire: intel: refine runtime pm for SDW_INTEL_CLK_STOP_BUS_RESET Date: Mon, 17 Aug 2020 23:29:23 +0800 Message-Id: <20200817152923.3259-13-yung-chuan.liao@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200817152923.3259-1-yung-chuan.liao@linux.intel.com> References: <20200817152923.3259-1-yung-chuan.liao@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rander Wang When all the links are suspended, the HDaudio controller may suspend and the power rails to the SoundWire IP may be disabled, requiring a complete re-initialization/enumeration on resume. However, if one or more Masters remained active, the HDaudio controller will remain active and the power rails will remain enabled. As a result, during the link resume step we can check if the context was preserved by verifying if the clock was stopped, and avoid doing a complete bus reset and re-enumeration. Signed-off-by: Rander Wang Signed-off-by: Bard Liao --- drivers/soundwire/intel.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 2899445e2649..dbcbe2708563 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -1698,6 +1698,8 @@ static int intel_resume_runtime(struct device *dev) struct sdw_intel *sdw = cdns_to_intel(cdns); struct sdw_bus *bus = &cdns->bus; u32 clock_stop_quirks; + bool clock_stop0; + int status; int ret; if (bus->prop.hw_disabled) { @@ -1739,11 +1741,24 @@ static int intel_resume_runtime(struct device *dev) return ret; } + /* + * An exception condition occurs for the CLK_STOP_BUS_RESET + * case if one or more masters remain active. In this condition, + * all the masters are powered on for they are in the same power + * domain. Master can preserve its context for clock stop0, so + * there is no need to clear slave status and reset bus. + */ + clock_stop0 = sdw_cdns_is_clock_stop(&sdw->cdns); + /* * make sure all Slaves are tagged as UNATTACHED and * provide reason for reinitialization */ - sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET); + if (!clock_stop0) { + status = SDW_UNATTACH_REQUEST_MASTER_RESET; + sdw_clear_slave_status(bus, status); + } + ret = sdw_cdns_enable_interrupt(cdns, true); if (ret < 0) { @@ -1751,7 +1766,7 @@ static int intel_resume_runtime(struct device *dev) return ret; } - ret = sdw_cdns_clock_restart(cdns, true); + ret = sdw_cdns_clock_restart(cdns, !clock_stop0); if (ret < 0) { dev_err(dev, "unable to restart clock during resume\n"); return ret; -- 2.17.1