From patchwork Thu Jun 21 01:52:36 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthias Kaehlcke X-Patchwork-Id: 10478973 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 47EC16023A for ; Thu, 21 Jun 2018 01:54:22 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 39BE928A5C for ; Thu, 21 Jun 2018 01:54:22 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2E5D428A69; Thu, 21 Jun 2018 01:54:22 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AD35D28A5C for ; Thu, 21 Jun 2018 01:54:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754715AbeFUByN (ORCPT ); Wed, 20 Jun 2018 21:54:13 -0400 Received: from mail-pf0-f193.google.com ([209.85.192.193]:33026 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754586AbeFUBxK (ORCPT ); Wed, 20 Jun 2018 21:53:10 -0400 Received: by mail-pf0-f193.google.com with SMTP id b17-v6so693296pfi.0 for ; Wed, 20 Jun 2018 18:53:10 -0700 (PDT) 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; bh=uuTfTEyH7xqA35vIsTTQ8TYa2L1PgTCJf5g9yX7aHnU=; b=ExD2nrJdg5y7rLVaQia7YdkxCmgo6YQ1YyYR0TDJqhPBJ6PeQKfQhhI6IK9wYIUp+7 z3kpA2FyJEriWluH3Ot2JfSfgnM6jAGbNoFNZ0a/GwLyCjgr0mbdBOINj76PveQ7yKQR XYYmsBtYLwJewnVNc/0A2XydGzhkncaxjmZTWxeRF8TbRRziXmZyUmajDylFxkUNN+r6 3ZuuU9UBtfd80iCQ1j3/V/mbIJQ69KVRwHTb7va165XlElid1ymsZkeWYAllC9kRNmJY Ji3rNRrwIw1MyEBx6Oq0DVuZ2j9ULGelKLnv3ZgA9wgM8Q82b6JMCCMTS3TlPKcavwQe 5EEA== X-Gm-Message-State: APt69E0CaIMFnuXFlzCO5uGGSzjzJJgpYhUqpYtyCgDVyNzVrWsjqakw uiUkdHNbm5S8U8bETDW/qgmuog== X-Google-Smtp-Source: ADUXVKIUiwAos+STz3nAXeVJAG0OrEWYe8G74hD4vWnNqmu3l0aSjJ8PpY6zmC9eVBhXq/1Nc6coeA== X-Received: by 2002:a62:6141:: with SMTP id v62-v6mr25164748pfb.197.1529545990064; Wed, 20 Jun 2018 18:53:10 -0700 (PDT) Received: from mka.mtv.corp.google.com ([2620:0:1000:1501:8e2d:4727:1211:622]) by smtp.gmail.com with ESMTPSA id p12-v6sm6585877pfi.175.2018.06.20.18.53.08 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 20 Jun 2018 18:53:09 -0700 (PDT) From: Matthias Kaehlcke To: MyungJoo Ham Cc: Kyungmin Park , Chanwoo Choi , Arnd Bergmann , Greg Kroah-Hartman , Rob Herring , Mark Rutland , linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Brian Norris , Douglas Anderson , Enric Balletbo i Serra , "Rafael J . Wysocki" , Viresh Kumar , Lee Jones , Benson Leung , Olof Johansson , Matthias Kaehlcke Subject: [PATCH v4 11/12] misc: throttler: Add Chrome OS EC throttler Date: Wed, 20 Jun 2018 18:52:36 -0700 Message-Id: <20180621015237.100100-12-mka@chromium.org> X-Mailer: git-send-email 2.18.0.rc2.346.g013aa6912e-goog In-Reply-To: <20180621015237.100100-1-mka@chromium.org> References: <20180621015237.100100-1-mka@chromium.org> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The driver subscribes to throttling events from the Chrome OS embedded controller and enables/disables system throttling based on these events. Signed-off-by: Matthias Kaehlcke Reviewed-by: Enric Balletbo i Serra Reviewed-by: Brian Norris --- Changes in v4: - adapt to parent being struct cros_ec_dev instead of struct cros_ec_device - added 'Reviewed-by: Brian Norris ' tag Changes in v3: - change module license to GPL v2 as in the SPDX identifier - don't instantiate the throttler through the DT (instantiation by CrOS EC MFD in a separate patch) Changes in v2: - added SPDX line instead of license boiler-plate - use macro to avoid splitting line - changed variable name for throttler from 'cte' to 'ce_thr' - formatting fixes - Kconfig: removed odd dashes around 'help' - added 'Reviewed-by' tag --- drivers/misc/throttler/Kconfig | 10 ++ drivers/misc/throttler/Makefile | 1 + drivers/misc/throttler/cros_ec_throttler.c | 111 +++++++++++++++++++++ 3 files changed, 122 insertions(+) create mode 100644 drivers/misc/throttler/cros_ec_throttler.c diff --git a/drivers/misc/throttler/Kconfig b/drivers/misc/throttler/Kconfig index 8b2e63b2ef48..ef984c96f67b 100644 --- a/drivers/misc/throttler/Kconfig +++ b/drivers/misc/throttler/Kconfig @@ -20,4 +20,14 @@ menuconfig THROTTLER_DEBUG Choose N unless you want to debug throttler drivers. +config CROS_EC_THROTTLER + tristate "Throttler event monitor for the Chrome OS Embedded Controller" + depends on MFD_CROS_EC + help + This driver adds support to throttle the system in reaction to + Chrome OS EC events. + + To compile this driver as a module, choose M here: the + module will be called cros_ec_throttler. + endif # THROTTLER diff --git a/drivers/misc/throttler/Makefile b/drivers/misc/throttler/Makefile index c8d920cee315..d9b2a77dabc9 100644 --- a/drivers/misc/throttler/Makefile +++ b/drivers/misc/throttler/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_THROTTLER) += core.o +obj-$(CONFIG_CROS_EC_THROTTLER) += cros_ec_throttler.o diff --git a/drivers/misc/throttler/cros_ec_throttler.c b/drivers/misc/throttler/cros_ec_throttler.c new file mode 100644 index 000000000000..82a25415a264 --- /dev/null +++ b/drivers/misc/throttler/cros_ec_throttler.c @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for throttling triggered by events from the Chrome OS Embedded + * Controller. + * + * Copyright (C) 2018 Google, Inc. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define nb_to_ce_thr(nb) container_of(nb, struct cros_ec_throttler, nb) + +struct cros_ec_throttler { + struct cros_ec_device *ec; + struct throttler *throttler; + struct notifier_block nb; +}; + +static int cros_ec_throttler_event(struct notifier_block *nb, + unsigned long queued_during_suspend, void *_notify) +{ + struct cros_ec_throttler *ce_thr = nb_to_ce_thr(nb); + u32 host_event; + + host_event = cros_ec_get_host_event(ce_thr->ec); + if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_THROTTLE_START)) { + throttler_set_level(ce_thr->throttler, 1); + + return NOTIFY_OK; + } else if (host_event & + EC_HOST_EVENT_MASK(EC_HOST_EVENT_THROTTLE_STOP)) { + throttler_set_level(ce_thr->throttler, 0); + + return NOTIFY_OK; + } + + return NOTIFY_DONE; +} + +static int cros_ec_throttler_probe(struct platform_device *pdev) +{ + struct cros_ec_throttler *ce_thr; + struct device *dev = &pdev->dev; + struct cros_ec_dev *ec; + int ret; + + ce_thr = devm_kzalloc(dev, sizeof(*ce_thr), GFP_KERNEL); + if (!ce_thr) + return -ENOMEM; + + ec = dev_get_drvdata(pdev->dev.parent); + ce_thr->ec = ec->ec_dev; + + /* + * The core code uses the DT node of the throttler to identify its + * throttling devices and rates. The CrOS EC throttler is a sub-device + * of the CrOS EC MFD device and doesn't have its own device node. Use + * the node of the MFD device instead. + */ + dev->of_node = ce_thr->ec->dev->of_node; + + ce_thr->throttler = throttler_setup(dev); + if (IS_ERR(ce_thr->throttler)) + return PTR_ERR(ce_thr->throttler); + + dev_set_drvdata(dev, ce_thr); + + ce_thr->nb.notifier_call = cros_ec_throttler_event; + ret = blocking_notifier_chain_register(&ce_thr->ec->event_notifier, + &ce_thr->nb); + if (ret < 0) { + dev_err(dev, "failed to register notifier\n"); + throttler_teardown(ce_thr->throttler); + return ret; + } + + return 0; +} + +static int cros_ec_throttler_remove(struct platform_device *pdev) +{ + struct cros_ec_throttler *ce_thr = platform_get_drvdata(pdev); + + blocking_notifier_chain_unregister(&ce_thr->ec->event_notifier, + &ce_thr->nb); + + throttler_teardown(ce_thr->throttler); + + return 0; +} + +static struct platform_driver cros_ec_throttler_driver = { + .driver = { + .name = "cros-ec-throttler", + }, + .probe = cros_ec_throttler_probe, + .remove = cros_ec_throttler_remove, +}; + +module_platform_driver(cros_ec_throttler_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Matthias Kaehlcke "); +MODULE_DESCRIPTION("Chrome OS EC Throttler");