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=-15.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,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 845F8C433FE for ; Sat, 5 Dec 2020 15:01:49 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A55BE22287 for ; Sat, 5 Dec 2020 15:01:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A55BE22287 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 1D21D1904; Sat, 5 Dec 2020 16:00:57 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 1D21D1904 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1607180507; bh=CbUbYFXxq7Z9BtRWpeR3Kpkooa9tNRsj40xyE9azA5k=; h=Subject:To:References:From:Date:In-Reply-To:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=tPjFvlrxN9qGBcb7nedp/xGVMXVNR1Z5TjEqXxp1jb+FRDx3G89ZarEuWaaQQHs7s 7CE7gWI9ZhuhcR5G+XF1mkBwFWDsaDZNTJPvQFlEm1sHQHlOTZAv1PW6snc7L/YIsn GH0M49yaSUMB3aETC2HeCcs8TV0IJWWfCX6iubuw= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id AB525F804B2; Sat, 5 Dec 2020 16:00:09 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 8E3F8F804BC; Sat, 5 Dec 2020 16:00:07 +0100 (CET) Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 96AC7F8025F for ; Sat, 5 Dec 2020 15:59:59 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 96AC7F8025F IronPort-SDR: JOwgChd/iQNexmmrShSQfRqRUHOUJxkYwqZ+kQmuBCYgn7BAmVg/qZ35g6rh8MvO87uECkdX+G XtLtbwxYzUOg== X-IronPort-AV: E=McAfee;i="6000,8403,9825"; a="237628585" X-IronPort-AV: E=Sophos;i="5.78,395,1599548400"; d="scan'208";a="237628585" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Dec 2020 06:59:56 -0800 IronPort-SDR: RYoMDGFFTE6jxc6pGLX2RQcbEpvcChRMU2DhisSbvvl+p0aMw7PNIZxacFcm8U16RJ6X5brham vKsXrkEViP1Q== X-IronPort-AV: E=Sophos;i="5.78,395,1599548400"; d="scan'208";a="436104270" Received: from schamb2-mobl2.amr.corp.intel.com (HELO [10.212.89.161]) ([10.212.89.161]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Dec 2020 06:59:55 -0800 Subject: Re: [PATCH 1/7] soundwire: bus: use sdw_update_no_pm when initializing a device To: Vinod Koul , Bard Liao References: <20201202204645.23891-1-yung-chuan.liao@linux.intel.com> <20201202204645.23891-2-yung-chuan.liao@linux.intel.com> <20201205074508.GQ8403@vkoul-mobl> From: Pierre-Louis Bossart Message-ID: <1db93c2e-3c87-bc5e-ddeb-56424870b897@linux.intel.com> Date: Sat, 5 Dec 2020 08:59:01 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20201205074508.GQ8403@vkoul-mobl> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Cc: alsa-devel@alsa-project.org, tiwai@suse.de, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, ranjani.sridharan@linux.intel.com, hui.wang@canonical.com, broonie@kernel.org, srinivas.kandagatla@linaro.org, jank@cadence.com, sanyog.r.kale@intel.com, rander.wang@linux.intel.com, bard.liao@intel.com X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" Thanks for the review Vinod. On 12/5/20 1:45 AM, Vinod Koul wrote: > On 03-12-20, 04:46, Bard Liao wrote: >> From: Pierre-Louis Bossart >> >> When a Slave device is resumed, it may resume the bus and restart the >> enumeration. During that process, we absolutely don't want to call >> regular read/write routines which will wait for the resume to >> complete, otherwise a deadlock occurs. >> >> Fixes: 60ee9be25571 ('soundwire: bus: add PM/no-PM versions of read/write functions') > > Change looks okay, but not sure why this is a fix for adding no pm > version? when we added the no_pm version, we missed the two cases below where sdw_update() was used and that creates a deadlock. To me that's a conceptual bug, we didn't fully use the no_pm versions, hence the Fixes tag. It's ok to remove the tag if you don't think it's useful/relevant, what matters is that we agree on the content. >> Signed-off-by: Pierre-Louis Bossart >> Reviewed-by: Rander Wang >> Signed-off-by: Bard Liao >> --- >> drivers/soundwire/bus.c | 16 ++++++++++++++-- >> 1 file changed, 14 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c >> index d1e8c3a54976..60c42508c6c6 100644 >> --- a/drivers/soundwire/bus.c >> +++ b/drivers/soundwire/bus.c >> @@ -489,6 +489,18 @@ sdw_read_no_pm(struct sdw_slave *slave, u32 addr) >> return buf; >> } >> >> +static int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val) >> +{ >> + int tmp; >> + >> + tmp = sdw_read_no_pm(slave, addr); >> + if (tmp < 0) >> + return tmp; >> + >> + tmp = (tmp & ~mask) | val; >> + return sdw_write_no_pm(slave, addr, tmp); >> +} >> + >> /** >> * sdw_nread() - Read "n" contiguous SDW Slave registers >> * @slave: SDW Slave >> @@ -1256,7 +1268,7 @@ static int sdw_initialize_slave(struct sdw_slave *slave) >> val = slave->prop.scp_int1_mask; >> >> /* Enable SCP interrupts */ >> - ret = sdw_update(slave, SDW_SCP_INTMASK1, val, val); >> + ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val); >> if (ret < 0) { >> dev_err(slave->bus->dev, >> "SDW_SCP_INTMASK1 write failed:%d\n", ret); >> @@ -1271,7 +1283,7 @@ static int sdw_initialize_slave(struct sdw_slave *slave) >> val = prop->dp0_prop->imp_def_interrupts; >> val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE; >> >> - ret = sdw_update(slave, SDW_DP0_INTMASK, val, val); >> + ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val); >> if (ret < 0) >> dev_err(slave->bus->dev, >> "SDW_DP0_INTMASK read failed:%d\n", ret); >> -- >> 2.17.1 >