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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 68057C43381 for ; Tue, 5 Mar 2019 00:51:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3366920675 for ; Tue, 5 Mar 2019 00:51:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="F9HZQyPH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726699AbfCEAvo (ORCPT ); Mon, 4 Mar 2019 19:51:44 -0500 Received: from mail-pf1-f195.google.com ([209.85.210.195]:46862 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726066AbfCEAvo (ORCPT ); Mon, 4 Mar 2019 19:51:44 -0500 Received: by mail-pf1-f195.google.com with SMTP id g6so4261671pfh.13 for ; Mon, 04 Mar 2019 16:51:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=xtFDP0NyHQVf3wQ/4BEnM3Byem+j8CITtmysXnmiB+w=; b=F9HZQyPH/FylBavycB1ngHKkskFl7KqfC6tJvyeKfQPkqZhStmLiSUhgK8Opu4E7mM P7Yy4m3jgNB3eSwNr8gFY7pNfmiCJQUPe6ysye6mIKiwm/6+f5uQU1jcpBJ0CbJmZKbd lXJ2OXqNDr1GKjExiKOQSwBHzcBO0ge07CyTg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=xtFDP0NyHQVf3wQ/4BEnM3Byem+j8CITtmysXnmiB+w=; b=mmEwlFYWh2RShVyIFZnklE31BXsgWjTPxcEf4zKIixEEXqacjuPf3vAlnierTAX6Rl b+kfnQ9scpRUqZXARkG4QQTC2ECcL95CJ4T26/icWR8IFFRjjiFXOvUG2RwJajtiYLpv OJDi+e/U0Sr8HgdPCABcujJlBRooqegdyJm0doUIzaJCcmJz6fPDCredphcz9z9fMDOj DdaEhily423WWcdLxCgR+mZqPGLaZh8DfzOZ0eRXEQkr9nhENgOZN2Z7H/ySV/ozeH5I Jm+dZNrZ1XPEBwAATVvWqsyGChwJQCbMu59AyeaAMqZxcdfCjAkTjcy/cH71qDz3/Bqf v0zw== X-Gm-Message-State: APjAAAUVN8OKIBVstc75JLw30w+JSsusSZ3TYp/eV+eyLSDMqYjjImfx B8iG1cqt4g0f3qUPbQtQ+4y/jg== X-Google-Smtp-Source: AHgI3IaR4TmnOEJH+UgkGwQd/ONyl/qtoVZUu4gsIBQICVOjgb8FPJRFo/PUoey7JSe/JtdsnFRPzQ== X-Received: by 2002:aa7:8205:: with SMTP id k5mr22338888pfi.86.1551747103252; Mon, 04 Mar 2019 16:51:43 -0800 (PST) Received: from ravisadineni0.mtv.corp.google.com ([2620:15c:202:1:98d2:1663:78dd:3593]) by smtp.gmail.com with ESMTPSA id c130sm14800562pfb.145.2019.03.04.16.51.42 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 04 Mar 2019 16:51:42 -0800 (PST) From: RaviChandra Sadineni To: ravisadineni@chromium.org Cc: Benson Leung , Enric Balletbo i Serra , Guenter Roeck , linux-kernel@vger.kernel.org, tbroch@google.com, dnojiri@google.com Subject: [PATCH V3] cros_ec: Expose sysfile to force battery cut-off on shutdown. Date: Mon, 4 Mar 2019 16:51:38 -0800 Message-Id: <20190305005138.129020-1-ravisadineni@chromium.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On chromebooks, power_manager daemon normally shutsdown(S5) the device when the battery charge falls below 4% threshold. Chromeos EC then normally spends an hour in S5 before hibernating. If the battery charge falls below critical threshold in the mean time, EC does a battery cutoff instead of hibernating. On some chromebooks, S5 is optimal enough resulting in EC hibernating without battery cut-off. This results in battery deep-discharging. This is a bad user experience as battery has to trickle charge before booting when the A.C is plugged in the next time. This patch exposes a sysfs file for an userland daemon to suggest EC if it has to do a battery cut-off instead of hibernating when the system enters S5 next time. Signed-off-by: RaviChandra Sadineni --- V3: Make battery-cutoff generic and expose 'at-shutdown' flag. V2: Use kstrtobool() instead of kstrtou8() and add documentation. .../ABI/testing/sysfs-class-chromeos | 10 ++++ drivers/platform/chrome/cros_ec_sysfs.c | 48 +++++++++++++++++++ 2 files changed, 58 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-chromeos diff --git a/Documentation/ABI/testing/sysfs-class-chromeos b/Documentation/ABI/testing/sysfs-class-chromeos new file mode 100644 index 000000000000..d5ab22c44977 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-chromeos @@ -0,0 +1,10 @@ +What: /sys/class/chromeos/cros_ec/battery-cuttoff +Date: February 2019 +Contact: Ravi Chandra Sadineni +Description: + cros_ec battery cuttoff configuration. Only option + currently exposed is 'at-shutdown'. + + 'at-shutdown' sends a host command to EC requesting + battery cutoff on next shutdown. If AC is plugged + in before next shutdown, EC ignores the request. diff --git a/drivers/platform/chrome/cros_ec_sysfs.c b/drivers/platform/chrome/cros_ec_sysfs.c index f34a50121064..6ef6b860c818 100644 --- a/drivers/platform/chrome/cros_ec_sysfs.c +++ b/drivers/platform/chrome/cros_ec_sysfs.c @@ -322,14 +322,62 @@ static ssize_t kb_wake_angle_store(struct device *dev, return count; } +/* Battery cut-off control */ +static ssize_t battery_cutoff_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct ec_params_battery_cutoff *param; + struct cros_ec_command *msg; + int ret; + struct cros_ec_dev *ec = + container_of(dev, struct cros_ec_dev, class_dev); + char *p; + int len; + + msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + param = (struct ec_params_battery_cutoff *)msg->data; + msg->command = EC_CMD_BATTERY_CUT_OFF + ec->cmd_offset; + msg->version = 1; + msg->outsize = sizeof(*param); + msg->insize = 0; + + p = memchr(buf, '\n', count); + len = p ? p - buf : count; + + if (len == 11 && !strncmp(buf, "at-shutdown", len)) { + param->flags = EC_BATTERY_CUTOFF_FLAG_AT_SHUTDOWN; + } else { + kfree(msg); + return -EINVAL; + } + + ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg); + kfree(msg); + if (ret < 0) + return ret; + return count; +} + /* Module initialization */ static DEVICE_ATTR_RW(reboot); static DEVICE_ATTR_RO(version); static DEVICE_ATTR_RO(flashinfo); static DEVICE_ATTR_RW(kb_wake_angle); +/* + * Currently EC does not expose a host command to read the status of + * battery cut-off configuration. Also there is no requirement to read + * the status of these flags from userland. So marking this attribute as + * write-only. + */ +static DEVICE_ATTR_WO(battery_cutoff); static struct attribute *__ec_attrs[] = { + &dev_attr_battery_cutoff.attr, &dev_attr_kb_wake_angle.attr, &dev_attr_reboot.attr, &dev_attr_version.attr, -- 2.20.1 story | grep send-email