From patchwork Tue Apr 6 01:36:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Badhri Jagan Sridharan X-Patchwork-Id: 416126 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT,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 97353C43461 for ; Tue, 6 Apr 2021 01:37:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 67CF2613FF for ; Tue, 6 Apr 2021 01:37:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243200AbhDFBhK (ORCPT ); Mon, 5 Apr 2021 21:37:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44242 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243176AbhDFBhG (ORCPT ); Mon, 5 Apr 2021 21:37:06 -0400 Received: from mail-pf1-x449.google.com (mail-pf1-x449.google.com [IPv6:2607:f8b0:4864:20::449]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 56DC4C06178C for ; Mon, 5 Apr 2021 18:36:59 -0700 (PDT) Received: by mail-pf1-x449.google.com with SMTP id e6so10015591pfe.3 for ; Mon, 05 Apr 2021 18:36:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=lIyNvwnE/mS/ZjxslbGipf8ebUbSEhxfFtLwaEqMPBs=; b=RaAPJILqbTmv3/2qmy4ysmj0jZdRajrgxhgYz8+HTSaaGnxayGZmHd7Z8YSYQRq9HD VaorHYtXCgKsM6SeKZSMzitaMJE7IK/Eolo9OYJAwSbmMfpuP/ntLHNnORP5CsaCsUgY u9P+5oR5hqmBMtGibQIdkhtekWdtSkakTWCwrglMDsYXX/9dO0lUdLbvv4DnjKTQM3zV zvVm8f7Q1+jqHpesqjJ3goz1WrVQ7jvOT1PGtMeV8AQS6Umsk+o+c76QoNFCbe4i5Rxb kbk6KaliFQNedvXUlh2r82dWpQL64EUfNL6pYDuWdcRoZCKXYjz9rOIQwIk6f6TalPpO lBnA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=lIyNvwnE/mS/ZjxslbGipf8ebUbSEhxfFtLwaEqMPBs=; b=uKwCIl/J/ZXa2kUa/S7DdO8GjS7zn6XELhsPtRX16mtAmeSzELZW8F1RkYuUBQrBF2 TCQtrgFcVSN0m/6d3Wqsk27H4lB6sE8OdX1r4bEIoRbzvFFJKJyRbIXGH30AZmjK0Zig bbh0kzw/pn8fXNKKE6KanTWj8JGV/sglIlC/ERryh9siAvSZvqTNBAkFZ2F4+dS/9pDw RgoeUad8d/IgFGJseLDTBA/aeEmFJ+7gKPO3ZWswIUGtiuCN/NM2YPjoELJ4kkLtqR9A C6+60LyUsZA5s4Sj2TmZi70o+Cqok5MBszY6LnxHFOI7ItG7sFLBV2zFflaZpvJI0s1v HzDQ== X-Gm-Message-State: AOAM53102DzwBbkzHwBmUu5FzVakOVZDLbB/RP0L2beZAgLA+7Un1Xrj JKd3adUPrpK8RN+WNBobwSjG7CkIa6I= X-Google-Smtp-Source: ABdhPJwNGOWuTQGYkY/hNl4HTn52fG8lx9PtBdR72CpxJ/jTcfOSmeNJdXGYcTVMqQNhqaXjmUXRnH3XOy8= X-Received: from badhri.mtv.corp.google.com ([2620:15c:211:201:7080:32f9:cd15:6178]) (user=badhri job=sendgmr) by 2002:a17:902:8303:b029:e6:4ef3:4f17 with SMTP id bd3-20020a1709028303b02900e64ef34f17mr26016796plb.22.1617673018706; Mon, 05 Apr 2021 18:36:58 -0700 (PDT) Date: Mon, 5 Apr 2021 18:36:42 -0700 In-Reply-To: <20210406013643.3280369-1-badhri@google.com> Message-Id: <20210406013643.3280369-6-badhri@google.com> Mime-Version: 1.0 References: <20210406013643.3280369-1-badhri@google.com> X-Mailer: git-send-email 2.31.0.208.g409f899ff0-goog Subject: [PATCH v1 5/6] usb: typec: tcpm: Allow slow charging loops to comply to pSnkStby From: Badhri Jagan Sridharan To: Guenter Roeck , Heikki Krogerus , Greg Kroah-Hartman , Rob Herring , Adam Thomson Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Kyle Tso , Badhri Jagan Sridharan Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org When a PD charger advertising Rp-3.0 is connected to a sink port, the sink port current limit would 3A, during SNK_DISCOVERY, till power negotiation starts. Once the negotiation starts the power limit needs to drop down to pSnkStby(500mA @ 5V) and to negotiated current limit once the explicit contract is in place. Not all charging loops can ramp up to 3A and drop down to 500mA within tSnkStdby which is 15ms. The port partner might hard reset if tSnkStdby is not met. To solve this problem, this patch introduces slow-charger-loop which when set makes the port request PD_P_SNK_STDBY_MW upon entering SNK_DISCOVERY(instead of 3A or the 1.5A during SNK_DISCOVERY) and the actual currrent limit after RX of PD_CTRL_PSRDY for PD link or during SNK_READY for non-pd link. Signed-off-by: Badhri Jagan Sridharan --- drivers/usb/typec/tcpm/tcpm.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index de9e57a7a929..6aa314005f57 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -455,6 +455,12 @@ struct tcpm_port { /* Auto vbus discharge status */ bool auto_vbus_discharge_enabled; + /* + * When set, port requests PD_P_SNK_STDBY_MW upon entering SNK_DISCOVERY and + * the actual currrent limit after RX of PD_CTRL_PSRDY for PD link, + * SNK_READY for non-pd link. + */ + bool slow_charger_loop; #ifdef CONFIG_DEBUG_FS struct dentry *dentry; struct mutex logbuffer_lock; /* log buffer access lock */ @@ -4043,9 +4049,12 @@ static void run_state_machine(struct tcpm_port *port) break; case SNK_DISCOVERY: if (port->vbus_present) { - tcpm_set_current_limit(port, - tcpm_get_current_limit(port), - 5000); + u32 current_lim = (!port->slow_charger_loop || + (tcpm_get_current_limit(port) <= + PD_P_SNK_STDBY_MW / 5)) ? + tcpm_get_current_limit(port) : + PD_P_SNK_STDBY_MW / 5; + tcpm_set_current_limit(port, current_lim, 5000); tcpm_set_charge(port, true); tcpm_set_state(port, SNK_WAIT_CAPABILITIES, 0); break; @@ -4157,6 +4166,8 @@ static void run_state_machine(struct tcpm_port *port) port->pwr_opmode = TYPEC_PWR_MODE_PD; } + if (!port->pd_capable && port->slow_charger_loop) + tcpm_set_current_limit(port, tcpm_get_current_limit(port), 5000); tcpm_swap_complete(port, 0); tcpm_typec_connect(port); mod_enable_frs_delayed_work(port, 0); @@ -5759,6 +5770,7 @@ static int tcpm_fw_get_caps(struct tcpm_port *port, port->typec_caps.type = ret; port->port_type = port->typec_caps.type; + port->slow_charger_loop = fwnode_property_read_bool(fwnode, "slow-charger-loop"); if (port->port_type == TYPEC_PORT_SNK) goto sink;