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=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 F13C4C433E0 for ; Wed, 12 Aug 2020 01:09:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CCF3E206B5 for ; Wed, 12 Aug 2020 01:09:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="hWeDtV4Q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726521AbgHLBJM (ORCPT ); Tue, 11 Aug 2020 21:09:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36566 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726329AbgHLBJM (ORCPT ); Tue, 11 Aug 2020 21:09:12 -0400 Received: from mail-vk1-xa41.google.com (mail-vk1-xa41.google.com [IPv6:2607:f8b0:4864:20::a41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A1E26C06174A for ; Tue, 11 Aug 2020 18:09:11 -0700 (PDT) Received: by mail-vk1-xa41.google.com with SMTP id r197so149219vkf.13 for ; Tue, 11 Aug 2020 18:09:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=88cHwPtOJkpAP2QyOkJeOazTV9eGumo2+yPMAU17QNo=; b=hWeDtV4Q0cxaQl5eDiVXgQPH8JPCVHEBulIJJLuPHISI1cTruMzZudIjl9aHanvhvt FsKwgJlZv915btRTXrDqH+bjSt6gf70n++ff8TCjI/KaEsU1ADN90ZMvEBgpLCsexEdI 3FbvBq4RhhHEH1KH6ietq1pq2137rpYlwNXXizbkaeaKB1s6xFYUbA4emZXzNPpS+MMF pagYEMBtLaZXAQoEMn477n4mRSxRBIIfLXqS7xLmzVVmAt90CEtbbpgYmPbL+GJi5IYs EUVruAke2qDcld5xAb+En1XDrSe45bexUj5mdEmqISIkBnk1FdP1rh6Y1JHL7nH1LJH/ 5X9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=88cHwPtOJkpAP2QyOkJeOazTV9eGumo2+yPMAU17QNo=; b=h97mZ+U/S5NOGrj0Gz6HM9sP5dJQFjcM5P/EdFIBerUBNiwkDvebxsLW+8MD4cWkaS lmEAV7HYtKELKf8tBZiNukbO9IReWcsv3QMnXTbZeclBwGQqR06TJoPAg5uK0eZTowui 5cYv10Dx8nidLfYVzipZ3Voct0nkxbiC4CAVVj67GOidR1x+lpjwKPUFREUV6h/cYpFF 2+gnta+y8gm8Q7ONdZabUZo+0HH+3duvDngcU5WKr6Hl6lAkqfYqbi1qPZ0A4sZF1zm8 sJrc6TUV8TcwblO4pDnNqt0xbTS1auBr5RGtYnGZPahjV/ypjxTOtU8oOTCGkVhy7d1I z/9A== X-Gm-Message-State: AOAM532MBiYrgSBwTwxVnePG5MS5+/h2UqqGfTWJe3XFXiLmdlp5yfKc e8M9jPiIQd3hLSPyslRM+pAu1FsoMgoY0HQxXnAbv/t2Yep/3A== X-Google-Smtp-Source: ABdhPJxmuQuQpYXondOloFtrJcG+LYXTBQnMOKOThFTfIekMcG9eoSrQDAkhsdoQJKgBe+kqaUQFdKmoe+lmGAi6HbE= X-Received: by 2002:a1f:206:: with SMTP id 6mr27879524vkc.79.1597194550083; Tue, 11 Aug 2020 18:09:10 -0700 (PDT) MIME-Version: 1.0 References: <20200811011126.130297-1-badhri@google.com> <20200811184507.GB86545@roeck-us.net> <8a2e77f4-1470-ebf0-402c-df90ab6332bb@roeck-us.net> In-Reply-To: From: Badhri Jagan Sridharan Date: Tue, 11 Aug 2020 18:08:33 -0700 Message-ID: Subject: Re: [PATCH v1] usb: typec: tcpm: Fix TDA 2.2.1.1 and TDA 2.2.1.2 failures To: Guenter Roeck Cc: Heikki Krogerus , Greg Kroah-Hartman , USB , LKML Content-Type: text/plain; charset="UTF-8" Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Yes I did ! https://lkml.org/lkml/2020/8/11/788 ! For me gmail is grouping V1 and V2 patches in the same thread so thought you saw the v2 patch :P Thanks, Badhri On Tue, Aug 11, 2020 at 5:36 PM Guenter Roeck wrote: > > On 8/11/20 4:21 PM, Badhri Jagan Sridharan wrote: > > Thanks Guenter ! However I don't see a reviewed-by tag :) > > > > Confused. Did you send a v2 with the changes we discussed ? > I didn't see that. > > Thanks, > Guenter > > > On Tue, Aug 11, 2020 at 1:18 PM Guenter Roeck wrote: > >> > >> On 8/11/20 12:39 PM, Badhri Jagan Sridharan wrote: > >>> On Tue, Aug 11, 2020 at 11:45 AM Guenter Roeck wrote: > >>>> > >>>> On Tue, Aug 11, 2020 at 11:24:07AM -0700, Badhri Jagan Sridharan wrote: > >>>>> On Mon, Aug 10, 2020 at 6:51 PM Guenter Roeck wrote: > >>>>>> > >>>>>> On 8/10/20 6:11 PM, Badhri Jagan Sridharan wrote: > >>>>>>> >From the spec: > >>>>>>> "7.1.5 Response to Hard Resets > >>>>>>> Hard Reset Signaling indicates a communication failure has occurred and > >>>>>>> the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin > >>>>>>> and Shall drive VBUS to vSafe0V as shown in Figure 7-9. The USB connection > >>>>>>> May reset during a Hard Reset since the VBUS voltage will be less than > >>>>>>> vSafe5V for an extended period of time. After establishing the vSafe0V > >>>>>>> voltage condition on VBUS, the Source Shall wait tSrcRecover before > >>>>>>> re-applying VCONN and restoring VBUS to vSafe5V. A Source Shall conform > >>>>>>> to the VCONN timing as specified in [USB Type-C 1.3]." > >>>>>>> > >>>>>>> Signed-off-by: Badhri Jagan Sridharan > >>>>>>> --- > >>>>>>> drivers/usb/typec/tcpm/tcpm.c | 16 +++++++++++++--- > >>>>>>> 1 file changed, 13 insertions(+), 3 deletions(-) > >>>>>>> > >>>>>>> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > >>>>>>> index 3ef37202ee37..e41c4e5d3c71 100644 > >>>>>>> --- a/drivers/usb/typec/tcpm/tcpm.c > >>>>>>> +++ b/drivers/usb/typec/tcpm/tcpm.c > >>>>>>> @@ -3372,13 +3372,19 @@ static void run_state_machine(struct tcpm_port *port) > >>>>>>> tcpm_set_state(port, SNK_HARD_RESET_SINK_OFF, 0); > >>>>>>> break; > >>>>>>> case SRC_HARD_RESET_VBUS_OFF: > >>>>>>> - tcpm_set_vconn(port, true); > >>>>>>> + /* > >>>>>>> + * 7.1.5 Response to Hard Resets > >>>>>>> + * Hard Reset Signaling indicates a communication failure has occurred and the > >>>>>>> + * Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall > >>>>>>> + * drive VBUS to vSafe0V as shown in Figure 7-9. > >>>>>>> + */ > >>>>>>> + tcpm_set_vconn(port, false); > >>>>>>> tcpm_set_vbus(port, false); > >>>>>>> tcpm_set_roles(port, port->self_powered, TYPEC_SOURCE, > >>>>>>> tcpm_data_role_for_source(port)); > >>>>>>> - tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER); > >>>>>> > >>>>>> I am a bit concerned about this. If I understand correctly, it means that > >>>>>> we won't turn VBUS back on unless a SRC_HARD_RESET_VBUS_OFF PD event is received. > >>>>>> Is that correct ? What happens if that event is never received ? > >>>>>> > >>>>>> Thanks, > >>>>>> Guenter > >>>>> > >>>>> The term PD event is a little ambiguous to me. Trying to summarize the workflow. > >>>>> Lower level tcpc driver would have to call tcpm_vbus_change which > >>>>> would in-turn trigger TCPM_VBUS_EVENT > >>>>> and queries port->tcpc->get_vbus to get the vbus status. It is not > >>>>> really a PD protocol driven event hence the > >>>>> confusion. > >>>>> > >>>>> "What happens if that event is never received ?" > >>>>> Yeah TCPM would be in SRC_HARD_RESET_VBUS_OFF till the tcpc calls the > >>>>> tcpm_vbus_change. > >>>>> Do you suspect that existing tcpc would not have the capability to > >>>>> monitor vbus status while sourcing and call tcpm_vbus_change? > >>>>> > >>>> That, or the driver might be buggy, or the hardware does't signal a status > >>>> update, or the update gets lost. I think we should have some backup, > >>>> to trigger if the event is not received in a reasonable amout of time. > >>>> I don't know if the specification has some kind of maximum limit. If > >>>> not, we should still have something > >>>> > >>>> Thanks, > >>>> Guenter > >>> > >>> Got it ! The specification actually has a bound for vbus off. > >>> tSafe0V - Time to reach vSafe0V max - 650ms. (PD_T_SAFE_0V). > >>> So I will bound it to that. > >>> > >> > >> Excellent. Thanks a lot for looking into this! > >> > >> Guenter > >> > >>> >From Table 7-12 Sequence Description for a Source Initiated Hard Reset: > >>> 4.Policy Engine waits tPSHardReset after sending Hard Reset Signaling > >>> and then tells the Device Policy Manager to instruct the power supply > >>> to perform a Hard Reset. The transition to vSafe0V Shall occur within > >>> tSafe0V (t2). > >>> 5 After tSrcRecover the Source applies power to VBUS in an attempt to > >>> re-establish communication with the Sink and resume USB Default > >>> Operation. The transition to vSafe5V Shall occur within tSrcTurnOn > >>> (t4). > >>> > >>> Thanks, > >>> Badhri > >>> > >>>> > >>>>> Thanks, > >>>>> Badhri > >>>>> > >>>>> > >>>>>>> break; > >>>>>>> case SRC_HARD_RESET_VBUS_ON: > >>>>>>> + tcpm_set_vconn(port, true); > >>>>>>> tcpm_set_vbus(port, true); > >>>>>>> port->tcpc->set_pd_rx(port->tcpc, true); > >>>>>>> tcpm_set_attached_state(port, true); > >>>>>>> @@ -3944,7 +3950,11 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port) > >>>>>>> tcpm_set_state(port, SNK_HARD_RESET_WAIT_VBUS, 0); > >>>>>>> break; > >>>>>>> case SRC_HARD_RESET_VBUS_OFF: > >>>>>>> - tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, 0); > >>>>>>> + /* > >>>>>>> + * After establishing the vSafe0V voltage condition on VBUS, the Source Shall wait > >>>>>>> + * tSrcRecover before re-applying VCONN and restoring VBUS to vSafe5V. > >>>>>>> + */ > >>>>>>> + tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER); > >>>>>>> break; > >>>>>>> case HARD_RESET_SEND: > >>>>>>> break; > >>>>>>> > >>>>>> > >> >