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=-8.2 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_SANE_1 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 4F855C3A5A8 for ; Wed, 4 Sep 2019 17:43:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 22D5921670 for ; Wed, 4 Sep 2019 17:43:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730408AbfIDRnw (ORCPT ); Wed, 4 Sep 2019 13:43:52 -0400 Received: from mga18.intel.com ([134.134.136.126]:35516 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725965AbfIDRnw (ORCPT ); Wed, 4 Sep 2019 13:43:52 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Sep 2019 10:43:50 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,467,1559545200"; d="scan'208";a="194813269" Received: from enagase-mobl1.amr.corp.intel.com (HELO [10.251.133.230]) ([10.251.133.230]) by orsmga002.jf.intel.com with ESMTP; 04 Sep 2019 10:43:49 -0700 Subject: Re: [alsa-devel] [PATCH 2/6] soundwire: cadence_master: add hw_reset capability in debugfs To: Vinod Koul Cc: alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, tiwai@suse.de, broonie@kernel.org, gregkh@linuxfoundation.org, jank@cadence.com, srinivas.kandagatla@linaro.org, slawomir.blauciak@intel.com, Sanyog Kale References: <20190813213227.5163-1-pierre-louis.bossart@linux.intel.com> <20190813213227.5163-3-pierre-louis.bossart@linux.intel.com> <20190904071317.GJ2672@vkoul-mobl> <71411347-93cf-2617-4edd-f6b401fe7a9b@linux.intel.com> <20190904164926.GA2672@vkoul-mobl> From: Pierre-Louis Bossart Message-ID: <63fc57dd-3df4-191c-2676-732f3748c55b@linux.intel.com> Date: Wed, 4 Sep 2019 12:43:49 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190904164926.GA2672@vkoul-mobl> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/4/19 11:49 AM, Vinod Koul wrote: > On 04-09-19, 08:18, Pierre-Louis Bossart wrote: >> On 9/4/19 2:13 AM, Vinod Koul wrote: >>> On 13-08-19, 16:32, Pierre-Louis Bossart wrote: >>>> 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 | 20 ++++++++++++++++++++ >>>> 1 file changed, 20 insertions(+) >>>> >>>> diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c >>>> index 046622e4b264..bd58d80ff636 100644 >>>> --- a/drivers/soundwire/cadence_master.c >>>> +++ b/drivers/soundwire/cadence_master.c >>>> @@ -340,6 +340,23 @@ 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 0; >>> >>> Should this not be EINVAL to indicate invalid value passed? >> >> Maybe. I must admit I don't know what -EINVAL would do, this is used for >> debugfs so it's not clear to me if the user will see a difference? > > Well user should see "write error: Invalid argument" when he writes > anything other than valid values :) ok then, will do.