From patchwork Wed Apr 7 20:07:22 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: 417153 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 62DD1C433B4 for ; Wed, 7 Apr 2021 20:07:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 12DE461159 for ; Wed, 7 Apr 2021 20:07:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1355926AbhDGUHw (ORCPT ); Wed, 7 Apr 2021 16:07:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37862 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1355911AbhDGUHt (ORCPT ); Wed, 7 Apr 2021 16:07:49 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C4A20C0613D9 for ; Wed, 7 Apr 2021 13:07:35 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id d1so24963060ybj.15 for ; Wed, 07 Apr 2021 13:07:35 -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=gni+OuRztGG9vq8fyGub8QeENwXoTEQ8rz4IMi+bKtk=; b=abqPz3iC0Y6rDJvYZsAExnpkiIDKRrjm0+5nGUT9yhzRp9RfNV/jYl8B1nitNgMzqS 2ojpx0ugRHKAa9LhyqZOMHQYP9volsOw6i3w1ZDzrbXF8DR+kU0wpfRAwcPTZ66kP5cq BptQtIDLbdeflTyXLSzUbycHzfjgpjRLN8LYNDgC8e2AgElqPIdKQsLk9thqdQnssaa+ 2W6T/AoW7w3GqcW33ldQoSvUT+CRExK09TNbl1DfAY01/J4SE9DSG4XH/Hq1Ve9Njl0j lQ9PMcWh4JRRQDXKB8uByXI4h54UanF17V+kF6vEpA+RMLNvfp+f+4BGFYuLO3Zk/ojB u7uA== 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=gni+OuRztGG9vq8fyGub8QeENwXoTEQ8rz4IMi+bKtk=; b=jOeN4J/VwoD+e54oaQ9xenQflBFRe9J+WtcU9HU+yuDWBQ/da2Vfs9VQyGO4NBfyVE nrRRn7ExQ2g23o1+QvY9adjLrqmf+ik39XEi7eOfwnlT+IOy971lo/duGS2Bt9wtmFGq N4rQfov2DKC126VJkmYFE5BYHlpyII/OymZwOoOEMhQBe+GV4a0wmC7zeFnvXAx6MsHI QYdHpgjNz2es2FsSAVTIJGZsHTVJGYwEi1bIAtVmJi5p4JnPbFJ0Wk/213yb1U9oBGgg jO3Z6yh09XzbFCiTH/HUONxZna+25vmGyFKr9TSRLbEhKgL/bYKTW2z6xPJ75onPtH1O vMgA== X-Gm-Message-State: AOAM530IxflTdw2/XcS1jjBWUvP4vE+3PkbJLORYrJnsTgn1zN9tIwob rlw+PPuIIDtbBXNAwVviwV50Jd/7RQ4= X-Google-Smtp-Source: ABdhPJykren/to6+VFAK9GoVBCT+QUQhMl3sOKzPJvq9xqM77MRf7+ZLoMPrGHCn+gHxaMhr6J/5+T8Xytw= X-Received: from badhri.mtv.corp.google.com ([2620:15c:211:201:991:6d08:9e6d:683d]) (user=badhri job=sendgmr) by 2002:a25:d07:: with SMTP id 7mr6804424ybn.135.1617826055040; Wed, 07 Apr 2021 13:07:35 -0700 (PDT) Date: Wed, 7 Apr 2021 13:07:22 -0700 In-Reply-To: <20210407200723.1914388-1-badhri@google.com> Message-Id: <20210407200723.1914388-5-badhri@google.com> Mime-Version: 1.0 References: <20210407200723.1914388-1-badhri@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v2 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 770b2edd9a04..b5bed6866a2b 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -459,6 +459,12 @@ 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 */ @@ -4047,9 +4053,12 @@ 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; @@ -4161,6 +4170,8 @@ 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); @@ -5763,6 +5774,7 @@ 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;