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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 40086C433EF for ; Mon, 15 Nov 2021 10:12:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2835A63211 for ; Mon, 15 Nov 2021 10:12:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237639AbhKOKOl (ORCPT ); Mon, 15 Nov 2021 05:14:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52786 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231127AbhKOKOP (ORCPT ); Mon, 15 Nov 2021 05:14:15 -0500 Received: from mail-lf1-x135.google.com (mail-lf1-x135.google.com [IPv6:2a00:1450:4864:20::135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 94B7CC061767; Mon, 15 Nov 2021 02:11:18 -0800 (PST) Received: by mail-lf1-x135.google.com with SMTP id b1so36244253lfs.13; Mon, 15 Nov 2021 02:11:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=uxwfsA+44ef1b7hlksCPyj8IFexX6NAJcsqLHIbZtDw=; b=ED1+rjMpnaWFy7IyLpgI4t6+NWjYrk9yvRsbDXQNO4edejFPeS5Fluo5T9eRA4iZWY qyAtRjrCuhzRvbF7arz5giRx/1OyeHYOPGZ8idBnsCSX89Lz1hbrQoL1Q4hSMMvQY/vY sRTdgNumGFp9+brp6ZmdJVdNJA1Y1oYxwd5Rsl/tcpXCmRMO0cstWd6ECUQhnVeqMk66 GMbaWu75HDQfPUtV03ha+oCfVVDZbuvVHXdBj/09cnQ8kjv4gtZmPvt4twaMUl5rf6qm V6HQpYyJTgipoGQBWZki3AkHxRPM7Nafs76W5lF1USMKUixqfNtzgAZBYmtw1Ok/Tfkq SMzQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=uxwfsA+44ef1b7hlksCPyj8IFexX6NAJcsqLHIbZtDw=; b=yHDloWQsuFZ0WRGEVlzKfVhUrOFkWqSB1jeId550atKckqs5StOQKDkZx+YQsT5LAR jnTDW12I9hSb6vaUsFwJIXzGEuXDSpxYKz/MwFYXHvUF0d6jA0ymje5W3mzhdgxFFxAk HXnIj0jErpYzPktDUK52PFw6Ch2G+U7rcCMURsu2nwxPvgQjwlT5N9MOk/XRGzaWWvsw f8NHhY315VT/xjjyzm7WFC+Z0JprD6X/JYLcztZFFljm+f5LihD4woqUwzdYaeVyM33B QIK54OQX/P+CkPJhf+VJLYU1MxYLi7pYx6oDfGooDRwnZQWW2hLp9K3Ehq/FwIAJ+Gug QNOw== X-Gm-Message-State: AOAM532nuAg4DbUHc5b0S+JUdX559GiByuNwTzUeruA4AUb+vzJ9LRZD ZlNH1zf1gtcArplj4Xbngw8= X-Google-Smtp-Source: ABdhPJzzG0A94HwBEFevyB5R/o6ZsnhSI8DcBgN+Z4YhggnKS037qGfUrVTsqxrckLGnY2R6XXXm3w== X-Received: by 2002:a05:6512:2201:: with SMTP id h1mr33409940lfu.397.1636971076884; Mon, 15 Nov 2021 02:11:16 -0800 (PST) Received: from localhost.localdomain ([178.127.153.223]) by smtp.gmail.com with ESMTPSA id f15sm1246622lfq.236.2021.11.15.02.11.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Nov 2021 02:11:16 -0800 (PST) Received: from jek by localhost.localdomain with local (Exim 4.95) (envelope-from ) id 1mmYxH-001Bq1-5o; Mon, 15 Nov 2021 13:11:15 +0300 Date: Mon, 15 Nov 2021 13:11:15 +0300 From: Yauhen Kharuzhy To: Hans de Goede Cc: "Rafael J . Wysocki" , Mika Westerberg , Mark Gross , Andy Shevchenko , Wolfram Sang , Sebastian Reichel , MyungJoo Ham , Chanwoo Choi , Ard Biesheuvel , Len Brown , linux-acpi@vger.kernel.org, Tsuchiya Yuto , platform-driver-x86@vger.kernel.org, linux-i2c@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org Subject: Re: [PATCH v2 10/20] power: supply: bq25890: Add bq25890_set_otg_cfg() helper Message-ID: References: <20211114170335.66994-1-hdegoede@redhat.com> <20211114170335.66994-11-hdegoede@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211114170335.66994-11-hdegoede@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Nov 14, 2021 at 06:03:25PM +0100, Hans de Goede wrote: > Add a bq25890_set_otg_cfg() helper function, this is a preparation > patch for adding regulator support. > > Signed-off-by: Hans de Goede > --- > drivers/power/supply/bq25890_charger.c | 28 ++++++++++++++------------ > 1 file changed, 15 insertions(+), 13 deletions(-) > > diff --git a/drivers/power/supply/bq25890_charger.c b/drivers/power/supply/bq25890_charger.c > index 2bdfb58cda75..3c41fe86b3d3 100644 > --- a/drivers/power/supply/bq25890_charger.c > +++ b/drivers/power/supply/bq25890_charger.c > @@ -801,6 +801,17 @@ static int bq25890_power_supply_init(struct bq25890_device *bq) > return PTR_ERR_OR_ZERO(bq->charger); > } > > +static int bq25890_set_otg_cfg(struct bq25890_device *bq, u8 val) > +{ > + int ret; > + > + ret = bq25890_field_write(bq, F_OTG_CFG, val); > + if (ret < 0) > + dev_err(bq->dev, "Error switching to boost/charger mode: %d\n", ret); Just a note: if a connected USB device has relative big capacitor at power wires inside, then a starting current pulse may be enough to overload the boost reguator and VBUS will not be powered. I met this at Yoga Book: the firmware set boost current limit to 1.4 A (default value for bq25892) but when USB hub connected, the BOOST_FAULT event appeared. To avoid this, Lenovo uses following trick in its kernel: set a boost current limit to big value (2.1 A), wait some time (500 ms) and set the current limit to right value (1.4A). This provides enough current to charge capacitors in the connected device but saves desired long-time limit to prevent overloading if the device consumes too much power itself. -- Yauhen Kharuzhy