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=-11.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_1 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 86E0DC433E1 for ; Mon, 17 Aug 2020 11:31:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 654532067C for ; Mon, 17 Aug 2020 11:31:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728415AbgHQLbL (ORCPT ); Mon, 17 Aug 2020 07:31:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728380AbgHQLay (ORCPT ); Mon, 17 Aug 2020 07:30:54 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 66897C061389 for ; Mon, 17 Aug 2020 04:30:54 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: eballetbo) with ESMTPSA id A3D2E28DA67 Subject: Re: [PATCH v2 1/2] platform/chrome: cros_ec_proto: ignore unnecessary wakeups on old ECs To: Brian Norris , Benson Leung , Guenter Roeck Cc: linux-kernel@vger.kernel.org References: <20200724190841.3112365-1-briannorris@chromium.org> From: Enric Balletbo i Serra Message-ID: <8a3b8af8-12d3-0566-49f2-cd763d7a2002@collabora.com> Date: Mon, 17 Aug 2020 13:30:48 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <20200724190841.3112365-1-briannorris@chromium.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Brian, On 24/7/20 21:08, Brian Norris wrote: > ECs that don't implement EC_CMD_HOST_EVENT_GET_WAKE_MASK should still > have some reasonable default mask -- otherwise, they'll treat a variety > of EC signals as spurious wakeups. Battery and AC events can be > especially common, for devices that have been sitting at full charge > plugged into AC for a long time, as they may cycle their charging off > and on, or their battery may start reporting failures as it ages. > > Treating these as wakeups does not serve a useful purpose, and is > instead often counterproductive. And indeed, later ECs (that implement > the mask) don't include these events in their wake-mask. > > Note that this patch doesn't do anything without the subsequent patch > ("platform/chrome: cros_ec_proto: check for missing > EC_CMD_HOST_EVENT_GET_WAKE_MASK"), because > cros_ec_get_host_event_wake_mask() currently does not return an error if > EC_CMD_HOST_EVENT_GET_WAKE_MASK is not implemented. > > Some additional notes: > While the EC typically knows not to wake the CPU for these unimportant > events once the CPU reaches a sleep state, it doesn't really have a way > to know that the CPU is "almost" asleep, unless it has support for > EC_CMD_HOST_SLEEP_EVENT. Alas, these older ECs do not support that > command either, so this solution is not 100% complete. > > Signed-off-by: Brian Norris Sorry for late notice. The patch has been applied for 5.9. > --- > v2: > * more notes in commit message > --- > drivers/platform/chrome/cros_ec_proto.c | 24 ++++++++++++++++++------ > 1 file changed, 18 insertions(+), 6 deletions(-) > > diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c > index 3e745e0fe092..e93024b55ce8 100644 > --- a/drivers/platform/chrome/cros_ec_proto.c > +++ b/drivers/platform/chrome/cros_ec_proto.c > @@ -469,14 +469,26 @@ int cros_ec_query_all(struct cros_ec_device *ec_dev) > &ver_mask); > ec_dev->host_sleep_v1 = (ret >= 0 && (ver_mask & EC_VER_MASK(1))); > > - /* > - * Get host event wake mask, assume all events are wake events > - * if unavailable. > - */ > + /* Get host event wake mask. */ > ret = cros_ec_get_host_event_wake_mask(ec_dev, proto_msg, > &ec_dev->host_event_wake_mask); > - if (ret < 0) > - ec_dev->host_event_wake_mask = U32_MAX; > + if (ret < 0) { > + /* > + * If the EC doesn't support EC_CMD_HOST_EVENT_GET_WAKE_MASK, > + * use a reasonable default. Note that we ignore various > + * battery, AC status, and power-state events, because (a) > + * those can be quite common (e.g., when sitting at full > + * charge, on AC) and (b) these are not actionable wake events; > + * if anything, we'd like to continue suspending (to save > + * power), not wake up. > + */ > + ec_dev->host_event_wake_mask = U32_MAX & > + ~(BIT(EC_HOST_EVENT_AC_DISCONNECTED) | > + BIT(EC_HOST_EVENT_BATTERY_LOW) | > + BIT(EC_HOST_EVENT_BATTERY_CRITICAL) | > + BIT(EC_HOST_EVENT_PD_MCU) | > + BIT(EC_HOST_EVENT_BATTERY_STATUS)); > + } > > ret = 0; > >