From patchwork Tue Jul 3 23:47:04 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthias Kaehlcke X-Patchwork-Id: 10505625 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 A46B7601D3 for ; Tue, 3 Jul 2018 23:48:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 95EBB28979 for ; Tue, 3 Jul 2018 23:48:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 89C582899B; Tue, 3 Jul 2018 23:48:30 +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 19A1928979 for ; Tue, 3 Jul 2018 23:48:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932272AbeGCXsN (ORCPT ); Tue, 3 Jul 2018 19:48:13 -0400 Received: from mail-pg0-f68.google.com ([74.125.83.68]:34478 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753661AbeGCXrk (ORCPT ); Tue, 3 Jul 2018 19:47:40 -0400 Received: by mail-pg0-f68.google.com with SMTP id y5-v6so1649578pgv.1 for ; Tue, 03 Jul 2018 16:47:39 -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=evgsf5Vq1O4jyiTSQjyAxO4d4xwVuctkoeX7GhDuJA4=; b=T/4TFgBLRD6ICnmg30hkUI3MqhC850rcI6tCZQmPjSi9Wx76sJ1y1T3YI2KuVDC3iT cuy0y3l26RXlSm3lL6rwhZADMCWX7RLKtnZQv78ysPqFLqzLTd/S3LZ2YdGEdV9n+YRT cNzOPqjuytlWxB+0Z0wPiPyJ/Bi/ISKSubTyeFH3GzfnjKB/m/o0QXODwuQGkmlT4YUe bnR+3yjdc66OjEx6iYCQzmDXLwGhvs5OG4NoLzTbpqZWj+JireleCrp0PSZ//DJZx5Cp 4YKZxdbb8piVLzpX5xWp7kTelaG1Rjt/xxN9uLPrVBYMCE1TSTkAAJylY99l4tgVWHR2 lVeQ== X-Gm-Message-State: APt69E2nDRTGtON6hSIIct7u1EXEQKUYlvmhMrFkQwkfghTW8edk/Ssd LLnhukO6UTqylIk+oCrl+Vs4/w== X-Google-Smtp-Source: ADUXVKLhkZC9eW4caWohFeHUzRLm85ApWJDHLm8jT0Q3fSNQC/tBOyD20ZpkVwAV770ImSSBc2nowg== X-Received: by 2002:a63:be4a:: with SMTP id g10-v6mr26943834pgo.378.1530661659339; Tue, 03 Jul 2018 16:47:39 -0700 (PDT) Received: from mka.mtv.corp.google.com ([2620:0:1000:1501:8e2d:4727:1211:622]) by smtp.gmail.com with ESMTPSA id l85-v6sm6608562pfk.79.2018.07.03.16.47.37 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 03 Jul 2018 16:47:38 -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 v5 11/12] misc: throttler: Add Chrome OS EC throttler Date: Tue, 3 Jul 2018 16:47:04 -0700 Message-Id: <20180703234705.227473-12-mka@chromium.org> X-Mailer: git-send-email 2.18.0.203.gfac676dfb9-goog In-Reply-To: <20180703234705.227473-1-mka@chromium.org> References: <20180703234705.227473-1-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 v5: - none 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");