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=-14.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 63382C43387 for ; Mon, 17 Dec 2018 12:29:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 270B4206A2 for ; Mon, 17 Dec 2018 12:29:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="LjYPYixP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732853AbeLQM3Y (ORCPT ); Mon, 17 Dec 2018 07:29:24 -0500 Received: from mail-qt1-f196.google.com ([209.85.160.196]:33846 "EHLO mail-qt1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732836AbeLQM3X (ORCPT ); Mon, 17 Dec 2018 07:29:23 -0500 Received: by mail-qt1-f196.google.com with SMTP id r14so13824686qtp.1 for ; Mon, 17 Dec 2018 04:29:21 -0800 (PST) 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=OzfSo9DWN6fzd05UazwSoUju6NS9mxZMerk1b/8SzVY=; b=LjYPYixPcAJkKrfAcd/jNQVxvdnS7+m0dak0/Xexs6G/I4khvTkiJI6aygInyvhGcs NudCGizN+G9YK5e80LynI2gZAdv6zDFcaTOL97XEDDED7d61TAtUEic5YsyvpEAUvfWy ADizS94NZE4dJjTnymMkEQ+mcJX7MlI0uaDcu7r1Hz90bcMZZ5DuGF62r6BeHGccyL7c +lMzvJfaZ9pLgl2cgc0Rd6hdgHTlHRhTxw1kIqWjFyThVjq7U0UfuywRKNIIJalpw5Dx f9DPj+xW+eVnk+SP6aitO4K9IsIIJ6VN9Oebasu7zCSlYcTncLzhk07EzvYmtx7/rn61 mQhA== 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=OzfSo9DWN6fzd05UazwSoUju6NS9mxZMerk1b/8SzVY=; b=t7R04wAaoz/8X/9nAoWnKEpU2Z7otiV65yE7d40urp0WKITqbFYQppWnXIXDuzSgD8 OOJkVssxPFlYdLxPxNhwzxfVbstE1wey+96lLPcN+P1zePiWyrRpg/Z1J62Or8xtPRRp XuDkcwf5AGwVSXd1S107TLxmQkELMf9ELTntWgVDTsgyUv1A5WngxFDJinCPSQ7qCZsd lNiSk3UnAJ8TdENeUpo2FHH6C9Gi4mFFz4fXzmRRX2kVWxxeMxnOaosKcBQrK6dnEbbp LTQfzCrs/JVbvkz/XnK9I8gQLCPo7pI+gKpThT9bGlKDu4zDknthgiaGMnzEZu+Dhg9x YGIg== X-Gm-Message-State: AA+aEWZ2h0e594aSaJooweNMDNm9EoSctsZtQd7JbXR3ULFIZOS3cWDH yKQjE0vN337Hfy7EdAgmwqdj//xCGdibFiY8vvQXKA== X-Google-Smtp-Source: AFSGD/VqwbZJFoqx1AuZ6lnqHvMVt79SswiSBziJsmQhtrCwRWxmlpKZthx/3erBxsrBCbECOlRMnsscyU/pZnhAwx8= X-Received: by 2002:a0c:b61b:: with SMTP id f27mr12773304qve.174.1545049760928; Mon, 17 Dec 2018 04:29:20 -0800 (PST) MIME-Version: 1.0 References: <20181217024805.122897-1-kyletso@google.com> <20181217113551.GA14121@kuha.fi.intel.com> In-Reply-To: <20181217113551.GA14121@kuha.fi.intel.com> From: Kyle Tso Date: Mon, 17 Dec 2018 20:29:09 +0800 Message-ID: Subject: Re: [PATCH] usb: typec: tcpm: Extend the matching rules on PPS APDO selection To: Heikki Krogerus Cc: Guenter Roeck , gregkh@linuxfoundation.org, Adam.Thomson.Opensource@diasemi.com, Badhri Jagan Sridharan , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 17, 2018 at 7:36 PM Heikki Krogerus wrote: > > On Mon, Dec 17, 2018 at 10:48:05AM +0800, Kyle Tso wrote: > > Current matching rules ensure that the voltage range of selected Source > > Capability is entirely within the range defined in one of the Sink > > Capabilities. This is reasonable but not practical because Sink may not > > support wide range of voltage when sinking power while Source could > > advertise its capabilities in raletively wider range. For example, a > > Source PDO advertising 3.3V-11V@3A (9V Prog of Fixed Nominal Voltage) > > will not be selected if the Sink requires 5V-12V@3A PPS power. However, > > the Sink could work well if the requested voltage range in RDOs is > > 5V-11V@3A. > > > > Currently accepted: > > |--------- source -----| > > |----------- sink ---------------| > > > > Currently not accepted: > > |--------- source -----| > > |----------- sink ---------------| > > > > |--------- source -----| > > |----------- sink ---------------| > > > > |--------- source -----------------| > > |------ sink -------| > > > > To improve the usability, change the matching rules to what listed > > below: > > a. The Source PDO is selectable if any portion of the voltage range > > overlaps one of the Sink PDO's voltage range. > > b. The maximum operational voltage will be the lower one between the > > selected Source PDO and the matching Sink PDO. > > c. The maximum power will be the maximum operational voltage times the > > maximum current defined in the selected Source PDO > > d. Select the Source PDO with the highest maximum power > > > > Signed-off-by: Kyle Tso > > Reviewed-by: Heikki Krogerus > > In case you'll do one more version, I have a minor comment about the > style below, but no need to resend only because of that. > > > --- > > Changelog since v1: > > - updated the commit message as suggested by Guenter Roeck > > --- > > drivers/usb/typec/tcpm/tcpm.c | 29 +++++++++++++++++------------ > > 1 file changed, 17 insertions(+), 12 deletions(-) > > > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > > index 3620efee2688..3001df7bd602 100644 > > --- a/drivers/usb/typec/tcpm/tcpm.c > > +++ b/drivers/usb/typec/tcpm/tcpm.c > > @@ -2213,7 +2213,8 @@ static unsigned int tcpm_pd_select_pps_apdo(struct tcpm_port *port) > > unsigned int i, j, max_mw = 0, max_mv = 0; > > unsigned int min_src_mv, max_src_mv, src_ma, src_mw; > > unsigned int min_snk_mv, max_snk_mv; > > - u32 pdo; > > + unsigned int max_op_mv; > > + u32 pdo, src, snk; > > unsigned int src_pdo = 0, snk_pdo = 0; > > > > /* > > @@ -2263,16 +2264,18 @@ static unsigned int tcpm_pd_select_pps_apdo(struct tcpm_port *port) > > continue; > > } > > > > - if (max_src_mv <= max_snk_mv && > > - min_src_mv >= min_snk_mv) { > > + if (min_src_mv <= max_snk_mv && > > + max_src_mv >= min_snk_mv) { > > + max_op_mv = min(max_src_mv, max_snk_mv); > > + src_mw = (max_op_mv * src_ma) / 1000; > > /* Prefer higher voltages if available */ > > if ((src_mw == max_mw && > > - min_src_mv > max_mv) || > > + max_op_mv > max_mv) || > > src_mw > max_mw) { > > src_pdo = i; > > snk_pdo = j; > > max_mw = src_mw; > > - max_mv = max_src_mv; > > + max_mv = max_op_mv; > > } > > } > > } > > @@ -2285,14 +2288,16 @@ static unsigned int tcpm_pd_select_pps_apdo(struct tcpm_port *port) > > } > > > > if (src_pdo) { > > - pdo = port->source_caps[src_pdo]; > > - > > - port->pps_data.min_volt = pdo_pps_apdo_min_voltage(pdo); > > - port->pps_data.max_volt = pdo_pps_apdo_max_voltage(pdo); > > - port->pps_data.max_curr = > > - min_pps_apdo_current(pdo, port->snk_pdo[snk_pdo]); > > + src = port->source_caps[src_pdo]; > > + snk = port->snk_pdo[snk_pdo]; > > + > > + port->pps_data.min_volt = max(pdo_pps_apdo_min_voltage(src), > > + pdo_pps_apdo_min_voltage(snk)); > > + port->pps_data.max_volt = min(pdo_pps_apdo_max_voltage(src), > > + pdo_pps_apdo_max_voltage(snk)); > > + port->pps_data.max_curr = min_pps_apdo_current(src, snk); > > port->pps_data.out_volt = > > - min(pdo_pps_apdo_max_voltage(pdo), port->pps_data.out_volt); > > + min(port->pps_data.max_volt, port->pps_data.out_volt); > > While here, you could have aligned that like the above lines: > > port->pps_data.out_volt = min(pdo_pps_apdo_max_voltage(pdo), > port->pps_data.out_volt); > Thanks Heikki Krogerus, I will fix this (and the lines below as well) in the next (should be V3) patch. > > port->pps_data.op_curr = > > min(port->pps_data.max_curr, port->pps_data.op_curr); > > } > > -- > > 2.20.0.405.gbc1bbc6f85-goog > > thanks, > > -- > heikki