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, 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 C4ED6C47E49 for ; Tue, 22 Oct 2019 23:55:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9C60820578 for ; Tue, 22 Oct 2019 23:55:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732978AbfJVXzC (ORCPT ); Tue, 22 Oct 2019 19:55:02 -0400 Received: from mga09.intel.com ([134.134.136.24]:15717 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731554AbfJVXy7 (ORCPT ); Tue, 22 Oct 2019 19:54:59 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 22 Oct 2019 16:54:59 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.68,218,1569308400"; d="scan'208";a="196612842" Received: from srajamoh-mobl2.amr.corp.intel.com (HELO pbossart-mobl3.intel.com) ([10.251.20.203]) by fmsmga008.fm.intel.com with ESMTP; 22 Oct 2019 16:54:57 -0700 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 v3 2/5] soundwire: cadence_master: add hw_reset capability in debugfs Date: Tue, 22 Oct 2019 18:54:45 -0500 Message-Id: <20191022235448.17586-3-pierre-louis.bossart@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191022235448.17586-1-pierre-louis.bossart@linux.intel.com> References: <20191022235448.17586-1-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 Provide debugfs capability to kick link and devices into hard-reset (as defined by MIPI). This capability is really useful when some devices are no longer responsive and/or to check the software handling of resynchronization. Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/cadence_master.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index 5337ccacccd1..7476e867468d 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -333,6 +333,26 @@ static int cdns_reg_show(struct seq_file *s, void *data) } DEFINE_SHOW_ATTRIBUTE(cdns_reg); +static int cdns_hw_reset(void *data, u64 value) +{ + struct sdw_cdns *cdns = data; + int ret; + + if (value != 1) + return -EINVAL; + + /* Userspace changed the hardware state behind the kernel's back */ + add_taint(TAINT_USER, LOCKDEP_STILL_OK); + + ret = sdw_cdns_exit_reset(cdns); + + dev_dbg(cdns->dev, "link hw_reset done: %d\n", ret); + + return ret; +} + +DEFINE_DEBUGFS_ATTRIBUTE(cdns_hw_reset_fops, NULL, cdns_hw_reset, "%llu\n"); + /** * sdw_cdns_debugfs_init() - Cadence debugfs init * @cdns: Cadence instance @@ -341,6 +361,9 @@ DEFINE_SHOW_ATTRIBUTE(cdns_reg); void sdw_cdns_debugfs_init(struct sdw_cdns *cdns, struct dentry *root) { debugfs_create_file("cdns-registers", 0400, root, cdns, &cdns_reg_fops); + + debugfs_create_file("cdns-hw-reset", 0200, root, cdns, + &cdns_hw_reset_fops); } EXPORT_SYMBOL_GPL(sdw_cdns_debugfs_init); -- 2.20.1