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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CABFEE645A for ; Fri, 15 Sep 2023 12:32:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234772AbjIOMcX (ORCPT ); Fri, 15 Sep 2023 08:32:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51990 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234900AbjIOMcW (ORCPT ); Fri, 15 Sep 2023 08:32:22 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A7121A5; Fri, 15 Sep 2023 05:32:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1694781136; x=1726317136; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=xhzmIM0A6FvMonQOUj08NuTR8MxP5gbC35qu4BkzgQU=; b=hvhXrms8WOU4AwB8pu+wENpl2CmBTiEb2ubzan2wYhsy8e7scvSunAaH rdIeEaNfyXKE+nM3hddpSD4ROtJnvmElnwUExpLoLtoPLY0QFet3YJkz0 72yy/CrBxmOHbBghLYzgCMcGgWwIY6nS4ZqlNxpkHjgopPMWcUwPeDPYk lKoQwyYoYyCHJaDpaJWZJt21Vkb8nFBujyhGCvbShNV3ynhD9ztaJ8eJM zuPcWuoBVm8Rlat+00+5nFRrWJ6Dg/QJvbseZH3odKMVkVBT9LNiQBrAl p89h1tFFSn0cqtVsMDWJgrne/siU5Q8szGXWPlIXzsAT+Z+hJHxbSpamC w==; X-IronPort-AV: E=McAfee;i="6600,9927,10834"; a="358651885" X-IronPort-AV: E=Sophos;i="6.02,149,1688454000"; d="scan'208";a="358651885" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Sep 2023 05:32:16 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10834"; a="774301594" X-IronPort-AV: E=Sophos;i="6.02,149,1688454000"; d="scan'208";a="774301594" Received: from kuha.fi.intel.com ([10.237.72.185]) by orsmga008.jf.intel.com with SMTP; 15 Sep 2023 05:32:13 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Fri, 15 Sep 2023 15:32:12 +0300 Date: Fri, 15 Sep 2023 15:32:12 +0300 From: Heikki Krogerus To: Prashanth K Cc: Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, "# 5 . 16" Subject: Re: usb: typec: ucsi: Clear EVENT_PENDING bit if ucsi_send_command fails Message-ID: References: <1694423055-8440-1-git-send-email-quic_prashk@quicinc.com> <21d247d3-83be-ba53-c982-2ab0e2e4ffb3@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <21d247d3-83be-ba53-c982-2ab0e2e4ffb3@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Tue, Sep 12, 2023 at 04:37:47PM +0530, Prashanth K wrote: > > > On 11-09-23 06:19 pm, Heikki Krogerus wrote: > > On Mon, Sep 11, 2023 at 02:34:15PM +0530, Prashanth K wrote: > > > Currently if ucsi_send_command() fails, then we bail out without > > > clearing EVENT_PENDING flag. So when the next connector change > > > event comes, ucsi_connector_change() won't queue the con->work, > > > because of which none of the new events will be processed. > > > > > > Fix this by clearing EVENT_PENDING flag if ucsi_send_command() > > > fails. > > > > > > Cc: # 5.16 > > > Fixes: 512df95b9432 ("usb: typec: ucsi: Better fix for missing unplug events issue") > > > Signed-off-by: Prashanth K > > > --- > > > drivers/usb/typec/ucsi/ucsi.c | 1 + > > > 1 file changed, 1 insertion(+) > > > > > > diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c > > > index c6dfe3d..509c67c 100644 > > > --- a/drivers/usb/typec/ucsi/ucsi.c > > > +++ b/drivers/usb/typec/ucsi/ucsi.c > > > @@ -884,6 +884,7 @@ static void ucsi_handle_connector_change(struct work_struct *work) > > > if (ret < 0) { > > > dev_err(ucsi->dev, "%s: GET_CONNECTOR_STATUS failed (%d)\n", > > > __func__, ret); > > > + clear_bit(EVENT_PENDING, &con->ucsi->flags); > > > goto out_unlock; > > > } > > > > I think it would be better to just move that label (out_unlock) above > > the point where clear_bit() is already called instead of separately > > calling it like that. That way the Connector Change Event will > > also get acknowledged. > Do we really need to ACK in this case since we didn't process the current > connector change event You won't get the next event before the first one was ACK'd, right? > > > > If this really can happen, then I think it would be good to also > > schedule a task for ucsi_check_connection(): > > > > if (ret < 0) { > > dev_err(ucsi->dev, "%s: GET_CONNECTOR_STATUS failed (%d)\n", > > __func__, ret); > > + ucsi_partner_task(con, ucsi_check_connection, 1, HZ); > > goto out_unlock; > > } > > > > thanks, > > > Retrying is a good idea, but ucsi_check_connection() doesn't have the full > functionality compared to handle_connector_change. I guess > ucsi_check_connection() will send a set_role, but won't handle the > connector_change scenarios happening due to PR/DR swap, which will lead to > deadlocks (due to wait_for_completion). This is just an example. So its > better to bail out and process the next events, because the failure here is > from the glink layer. Fair enough. -- heikki