From patchwork Wed Oct 24 19:34:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolin Chen X-Patchwork-Id: 10654899 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 854E014E2 for ; Wed, 24 Oct 2018 19:34:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 73CCD2839C for ; Wed, 24 Oct 2018 19:34:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 680732B0B9; Wed, 24 Oct 2018 19:34:40 +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=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham 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 B42A02839C for ; Wed, 24 Oct 2018 19:34:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725821AbeJYEDx (ORCPT ); Thu, 25 Oct 2018 00:03:53 -0400 Received: from mail-pl1-f193.google.com ([209.85.214.193]:44888 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727225AbeJYEDl (ORCPT ); Thu, 25 Oct 2018 00:03:41 -0400 Received: by mail-pl1-f193.google.com with SMTP id d23-v6so2682151pls.11; Wed, 24 Oct 2018 12:34:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=jZRxRcX58vlVGx5DKWx9aAIsUJCedGMpn9hiGaSCbQE=; b=OUB6CNtYorsuxgAcf3wXfwJsSR8ugZ7jkT2kQHPJtnO4xuJ5BXcjAQ00LCVtqX9b9O AjRudzgD2Wayxuiuj4Ryjj6HMUAcxe3LzSTUrt6XyH2UI3sZR/lxf+THwgiDtvZsl5aq cWbz0sKtS4tky7YJYE2yO71qOPoQqa45dVa6XvllyuEZIY2PBGPwclm6HpQsix6llWwK JY/KZ5BEdzRmZqy7wEwGLFvmADCGlOV2V7h6zK4oGVEVPnpN3QlRzBWWNvSLJsgRydHc 36Y+LjYN7oyK347YtRwToj9uYeWjME81TB6DLsSJVl/o5a3WayFPSEhRGliQoKF9g0u0 eCFA== 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=jZRxRcX58vlVGx5DKWx9aAIsUJCedGMpn9hiGaSCbQE=; b=n/qdAkXiwM8WtuJ42I2TIiuTkv/M7WNBsLTo6d/Jg0GnxEbKQ1EOLxarjJegE7WnKA MVCXyOcw2MkPEr70dLRfe27kPZvWH8HNBte4qXXHjj+Die7/OppWTvwDGg65U4aZ/4Aj rZU71nLQSe6EL2ADIcJzf3Ny/B6GpSFmnNBJ56BrT+ZEMekUOrlC6BHeI5rflo1WpOur oj+eZZY9B/zNyiEUscY4gc6bSlYt4j1peoLndc1S8dyASDhfIGzNnI8dEy0ydccaHrCV gHO26eWpKO7+6PWU5DTu5FCLTAjSck/ePRmIhXYmvxPkebNd7sB6PMisoMaERNrxijmH fwAw== X-Gm-Message-State: AGRZ1gLD+Gia38uR5mxvcGBpQNc7p8C9IaF5alBgwA1qboHvVMyhjTbE gitG1xB6Sgv7+B+HgHwSbRk= X-Google-Smtp-Source: AJdET5dIsk7U8vC0XupwawVVtbYjOYZAw+5h1dUR8FSMAFcc8fzbQ8rvcaImGh0YGadDkLcPIF8uOw== X-Received: by 2002:a17:902:748a:: with SMTP id h10-v6mr3657913pll.187.1540409659761; Wed, 24 Oct 2018 12:34:19 -0700 (PDT) Received: from Asurada-Nvidia.nvidia.com (thunderhill.nvidia.com. [216.228.112.22]) by smtp.gmail.com with ESMTPSA id r81-v6sm19921633pfa.110.2018.10.24.12.34.18 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 24 Oct 2018 12:34:19 -0700 (PDT) From: Nicolin Chen To: jdelvare@suse.com, linux@roeck-us.net Cc: linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 5/5] hwmon: (ina3221) Add PM runtime support Date: Wed, 24 Oct 2018 12:34:02 -0700 Message-Id: <20181024193402.16698-6-nicoleotsuka@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181024193402.16698-1-nicoleotsuka@gmail.com> References: <20181024193402.16698-1-nicoleotsuka@gmail.com> Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If all three channels are disabled via in[123]_enable ABI, the driver could suspend the chip for power saving purpose. So this patch adds the PM runtime support in order to gain more power control than system suspend and resume use case. For PM runtime, there are a few related changes happening: 1) Added a new explicit hdev device pointer for all the PM runtime callbacks. This is because hwmon core registers a child device for each hwmon driver. So there might be a mismatch between two device pointers in the driver if mixing using them. 2) Added a check in ina3221_is_enabled() to make sure that the chip is resumed. 3) Bypassed the unchanged status in ina3221_write_enable() in order to keep the PM runtime refcount being matched. 4) Removed the reset routine in the probe() by calling the resume() via pm_runtime_get_sync() instead, as they're similar. It's also necessary to do so to match initial PM refcount with the number of enabled channels. 5) Bypassed the system suspend/resume callbacks from the i2c_client->dev, because both the i2c_client->dev and the ina->hdev coexist and share the same pair of system suspend/resume callback functions, which means there'd be two suspend() calls during the system suspend while the second one will fail. Signed-off-by: Nicolin Chen --- Changelog v2->v3: * Improved a dev_err message * Added comments at pm_runtime_put_noidle() callbacks * Added pm_runtime header file in an alphabetical order v1->v2: * Bypassed i2c_client->dev in suspend/resume() * Added a missing '\n' in one dev_err() drivers/hwmon/ina3221.c | 113 ++++++++++++++++++++++++++++++++-------- 1 file changed, 91 insertions(+), 22 deletions(-) diff --git a/drivers/hwmon/ina3221.c b/drivers/hwmon/ina3221.c index 07dd6ef58d3e..3e7c6fac6e1b 100644 --- a/drivers/hwmon/ina3221.c +++ b/drivers/hwmon/ina3221.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #define INA3221_DRIVER_NAME "ina3221" @@ -53,6 +54,7 @@ #define INA3221_CONFIG_CHs_EN_MASK GENMASK(14, 12) #define INA3221_CONFIG_CHx_EN(x) BIT(14 - (x)) +#define INA3221_CONFIG_DEFAULT 0x7127 #define INA3221_RSHUNT_DEFAULT 10000 enum ina3221_fields { @@ -103,6 +105,7 @@ struct ina3221_input { /** * struct ina3221_data - device specific information + * @hdev: Device pointer of hwmon child device, used for pm runtime * @regmap: Register map of the device * @fields: Register fields of the device * @inputs: Array of channel input source specific structures @@ -110,6 +113,7 @@ struct ina3221_input { * @reg_config: Register value of INA3221_CONFIG */ struct ina3221_data { + struct device *hdev; struct regmap *regmap; struct regmap_field *fields[F_MAX_FIELDS]; struct ina3221_input inputs[INA3221_NUM_CHANNELS]; @@ -119,7 +123,8 @@ struct ina3221_data { static inline bool ina3221_is_enabled(struct ina3221_data *ina, int channel) { - return ina->reg_config & INA3221_CONFIG_CHx_EN(channel); + return pm_runtime_active(ina->hdev) && + (ina->reg_config & INA3221_CONFIG_CHx_EN(channel)); } /* Lookup table for Bus and Shunt conversion times in usec */ @@ -290,21 +295,48 @@ static int ina3221_write_enable(struct device *dev, int channel, bool enable) { struct ina3221_data *ina = dev_get_drvdata(dev); u16 config, mask = INA3221_CONFIG_CHx_EN(channel); + u16 config_old = ina->reg_config & mask; int ret; config = enable ? mask : 0; + /* Bypass if enable status is not being changed */ + if (config_old == config) + return 0; + + /* For enabling routine, increase refcount and resume() at first */ + if (enable) { + ret = pm_runtime_get_sync(ina->hdev); + if (ret < 0) { + dev_err(dev, "Failed to get PM runtime\n"); + return ret; + } + } + /* Enable or disable the channel */ ret = regmap_update_bits(ina->regmap, INA3221_CONFIG, mask, config); if (ret) - return ret; + goto fail; /* Cache the latest config register value */ ret = regmap_read(ina->regmap, INA3221_CONFIG, &ina->reg_config); if (ret) - return ret; + goto fail; + + /* For disabling routine, decrease refcount or suspend() at last */ + if (!enable) + pm_runtime_put_sync(ina->hdev); return 0; + +fail: + if (enable) { + dev_err(dev, "Failed to enable channel %d: error %d\n", + channel, ret); + pm_runtime_put_sync(ina->hdev); + } + + return ret; } static int ina3221_read(struct device *dev, enum hwmon_sensor_types type, @@ -599,7 +631,6 @@ static int ina3221_probe(struct i2c_client *client, { struct device *dev = &client->dev; struct ina3221_data *ina; - struct device *hwmon_dev; int i, ret; ina = devm_kzalloc(dev, sizeof(*ina), GFP_KERNEL); @@ -631,44 +662,72 @@ static int ina3221_probe(struct i2c_client *client, return ret; } - ret = regmap_field_write(ina->fields[F_RST], true); - if (ret) { - dev_err(dev, "Unable to reset device\n"); - return ret; - } - - /* Sync config register after reset */ - ret = regmap_read(ina->regmap, INA3221_CONFIG, &ina->reg_config); - if (ret) - return ret; + /* The driver will be reset, so use reset value */ + ina->reg_config = INA3221_CONFIG_DEFAULT; /* Disable channels if their inputs are disconnected */ for (i = 0; i < INA3221_NUM_CHANNELS; i++) { if (ina->inputs[i].disconnected) ina->reg_config &= ~INA3221_CONFIG_CHx_EN(i); } - ret = regmap_write(ina->regmap, INA3221_CONFIG, ina->reg_config); - if (ret) - return ret; mutex_init(&ina->lock); dev_set_drvdata(dev, ina); - hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, ina, + /* Fence sysfs nodes till pm_runtime is resumed */ + mutex_lock(&ina->lock); + + /* Use the returned hdev for pm_runtime */ + ina->hdev = devm_hwmon_device_register_with_info(dev, client->name, ina, &ina3221_chip_info, ina3221_groups); - if (IS_ERR(hwmon_dev)) { + if (IS_ERR(ina->hdev)) { dev_err(dev, "Unable to register hwmon device\n"); - mutex_destroy(&ina->lock); - return PTR_ERR(hwmon_dev); + ret = PTR_ERR(ina->hdev); + goto fail_lock; } + /* Enable PM runtime -- status is suspended by default */ + pm_runtime_enable(ina->hdev); + + /* Initialize (resume) the device */ + for (i = 0; i < INA3221_NUM_CHANNELS; i++) { + if (ina->inputs[i].disconnected) + continue; + /* Match the refcount with number of enabled channels */ + ret = pm_runtime_get_sync(ina->hdev); + if (ret < 0) + goto fail_pm; + } + + mutex_unlock(&ina->lock); + return 0; + +fail_pm: + pm_runtime_disable(ina->hdev); + pm_runtime_set_suspended(ina->hdev); + /* pm_runtime_put_noidle() will decrease the PM refcount until 0 */ + for (i = 0; i < INA3221_NUM_CHANNELS; i++) + pm_runtime_put_noidle(ina->hdev); +fail_lock: + mutex_unlock(&ina->lock); + mutex_destroy(&ina->lock); + + return ret; } static int ina3221_remove(struct i2c_client *client) { struct ina3221_data *ina = dev_get_drvdata(&client->dev); + int i; + + pm_runtime_disable(ina->hdev); + pm_runtime_set_suspended(ina->hdev); + + /* pm_runtime_put_noidle() will decrease the PM refcount until 0 */ + for (i = 0; i < INA3221_NUM_CHANNELS; i++) + pm_runtime_put_noidle(ina->hdev); mutex_destroy(&ina->lock); @@ -680,6 +739,10 @@ static int __maybe_unused ina3221_suspend(struct device *dev) struct ina3221_data *ina = dev_get_drvdata(dev); int ret; + /* Let hdev control all PM runtime callbacks */ + if (dev != ina->hdev) + return 0; + /* Save config register value and enable cache-only */ ret = regmap_read(ina->regmap, INA3221_CONFIG, &ina->reg_config); if (ret) @@ -703,6 +766,10 @@ static int __maybe_unused ina3221_resume(struct device *dev) struct ina3221_data *ina = dev_get_drvdata(dev); int ret; + /* Let hdev control all PM runtime callbacks */ + if (dev != ina->hdev) + return 0; + regcache_cache_only(ina->regmap, false); /* Software reset the chip */ @@ -726,7 +793,9 @@ static int __maybe_unused ina3221_resume(struct device *dev) } static const struct dev_pm_ops ina3221_pm = { - SET_SYSTEM_SLEEP_PM_OPS(ina3221_suspend, ina3221_resume) + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) + SET_RUNTIME_PM_OPS(ina3221_suspend, ina3221_resume, NULL) }; static const struct of_device_id ina3221_of_match_table[] = {