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: 12183925 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=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 EDF07C433B4 for ; Tue, 6 Apr 2021 01:37:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C89F6613E5 for ; Tue, 6 Apr 2021 01:37:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243208AbhDFBhN (ORCPT ); Mon, 5 Apr 2021 21:37:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44260 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243180AbhDFBhH (ORCPT ); Mon, 5 Apr 2021 21:37:07 -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 4EC7BC061760 for ; Mon, 5 Apr 2021 18:36:59 -0700 (PDT) Received: by mail-pf1-x449.google.com with SMTP id e8so311565pfd.1 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=QIGdr9x/FZQlC/09NXoU2ydwUdQ/DPanDbjrE1Y31uJoEqB96hTV0GZF3b/OIl3ION W4CcLbMZjrMFLZ3mBsLxGGkJyjeaDCoEAo7khh1xW1aNxP/b5GQNcouIM337+YK3kvWK 9Z3XB6YKqbI/K+I//0k/l91LGmcdFy8G9Q+PZTZJoBMhZ5LGRHJp0enkifouuYNxZrmL aGU7iWUlnGD43HaoA7eh/VztwsKiVlSjUC4jzMvoWoVjakfeDWgHWHktcb5ir/5lwyrB oFS26GJciQl+RUgpf1TbW3k9OtQbQXQiAuJd6YEADC4KmBWAdEUr53B8GRAQhZNPyvZT OtSA== X-Gm-Message-State: AOAM533LulZYsNUjD+mIBzvNLu0KayLHyZ1LTZsg4YGf47NttKAI1Iuk Ea3m248fTLqGiT/S8m2Wav3o11igGaQ= 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: linux-usb@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;