From patchwork Wed Jul 8 15:45:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 11651827 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D1F6414E3 for ; Wed, 8 Jul 2020 15:46:27 +0000 (UTC) Received: from web01.groups.io (web01.groups.io [66.175.222.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AB786207D0 for ; Wed, 8 Jul 2020 15:46:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=lists.cip-project.org header.i=@lists.cip-project.org header.b="MgD8Sp0H" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AB786207D0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=csie.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=bounce+64572+4887+4520428+8129116@lists.cip-project.org X-Received: by 127.0.0.2 with SMTP id QOcSYY4521763xMZ5UmJm2Jz; Wed, 08 Jul 2020 08:46:25 -0700 X-Received: from wens.tw (wens.tw [140.112.194.72]) by mx.groups.io with SMTP id smtpd.web10.13558.1594223180607576294 for ; Wed, 08 Jul 2020 08:46:21 -0700 X-Received: by wens.tw (Postfix, from userid 1000) id 135595FC7F; Wed, 8 Jul 2020 23:46:17 +0800 (CST) From: "Chen-Yu Tsai (Moxa)" To: nobuhiro1.iwamatsu@toshiba.co.jp, pavel@denx.de Cc: cip-dev@lists.cip-project.org, JohnsonCH.Chen@moxa.com Subject: [cip-dev] [PATCH 4.4.y-cip 01/23] PM / OPP: get/put regulators from OPP core Date: Wed, 8 Jul 2020 23:45:32 +0800 Message-Id: <20200708154554.26450-2-wens@csie.org> In-Reply-To: <20200708154554.26450-1-wens@csie.org> References: <20200708154554.26450-1-wens@csie.org> MIME-Version: 1.0 Precedence: Bulk List-Unsubscribe: Sender: cip-dev@lists.cip-project.org List-Id: Mailing-List: list cip-dev@lists.cip-project.org; contact cip-dev+owner@lists.cip-project.org Delivered-To: mailing list cip-dev@lists.cip-project.org Reply-To: cip-dev@lists.cip-project.org X-Gm-Message-State: 8ctxKqiY2NxSkKHaLAGLxCT8x4520428AA= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lists.cip-project.org; q=dns/txt; s=20140610; t=1594223185; bh=8PEHJ3IHykFyHUWcL9E08USq1ddhrdXF5Mxv3/n1gpU=; h=Cc:Content-Type:Date:From:Reply-To:Subject:To; b=MgD8Sp0HMlxNGWSuT3+b+FJGLqEJzjz7K4IVoSCndy2aAzmEQlGXTJnfv5KPJtMpECQ EX5WQV8KZE97yWbmdhoa99K5lVlWkgMUw8AQi9SbMPRHpDNyACT8wSzmOKajp13GHTdGx BXyi6cvmJ5eomVQEZp+aPFEVrnDIQheF2HY= From: Viresh Kumar commit 9f8ea969d5cfdd4353d2adb004e8e2286b984369 upstream. This allows the OPP core to request/free the regulator resource, attached to a device OPP. The regulator device is fetched using the name provided by the driver, while calling: dev_pm_opp_set_regulator(). This will work for both OPP-v1 and v2 bindings. This is a preliminary step for moving the OPP switching logic into the OPP core. Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki Signed-off-by: Chen-Yu Tsai (Moxa) --- drivers/base/power/opp/core.c | 111 ++++++++++++++++++++++++++++++++++ drivers/base/power/opp/opp.h | 4 ++ include/linux/pm_opp.h | 9 +++ 3 files changed, 124 insertions(+) diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index 1e0a2ddf73323..efdfcee48cac7 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "opp.h" @@ -565,6 +566,9 @@ static void _remove_device_opp(struct device_opp *dev_opp) if (dev_opp->prop_name) return; + if (!IS_ERR_OR_NULL(dev_opp->regulator)) + return; + list_dev = list_first_entry(&dev_opp->dev_list, struct device_list_opp, node); @@ -1091,6 +1095,113 @@ unlock: } EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name); +/** + * dev_pm_opp_set_regulator() - Set regulator name for the device + * @dev: Device for which regulator name is being set. + * @name: Name of the regulator. + * + * In order to support OPP switching, OPP layer needs to know the name of the + * device's regulator, as the core would be required to switch voltages as well. + * + * This must be called before any OPPs are initialized for the device. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function internally uses RCU updater strategy with mutex locks + * to keep the integrity of the internal data structures. Callers should ensure + * that this function is *NOT* called under RCU protection or in contexts where + * mutex cannot be locked. + */ +int dev_pm_opp_set_regulator(struct device *dev, const char *name) +{ + struct device_opp *dev_opp; + struct regulator *reg; + int ret; + + mutex_lock(&dev_opp_list_lock); + + dev_opp = _add_device_opp(dev); + if (!dev_opp) { + ret = -ENOMEM; + goto unlock; + } + + /* This should be called before OPPs are initialized */ + if (WARN_ON(!list_empty(&dev_opp->opp_list))) { + ret = -EBUSY; + goto err; + } + + /* Already have a regulator set */ + if (WARN_ON(!IS_ERR_OR_NULL(dev_opp->regulator))) { + ret = -EBUSY; + goto err; + } + /* Allocate the regulator */ + reg = regulator_get_optional(dev, name); + if (IS_ERR(reg)) { + ret = PTR_ERR(reg); + if (ret != -EPROBE_DEFER) + dev_err(dev, "%s: no regulator (%s) found: %d\n", + __func__, name, ret); + goto err; + } + + dev_opp->regulator = reg; + + mutex_unlock(&dev_opp_list_lock); + return 0; + +err: + _remove_device_opp(dev_opp); +unlock: + mutex_unlock(&dev_opp_list_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_opp_set_regulator); + +/** + * dev_pm_opp_put_regulator() - Releases resources blocked for regulator + * @dev: Device for which regulator was set. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function internally uses RCU updater strategy with mutex locks + * to keep the integrity of the internal data structures. Callers should ensure + * that this function is *NOT* called under RCU protection or in contexts where + * mutex cannot be locked. + */ +void dev_pm_opp_put_regulator(struct device *dev) +{ + struct device_opp *dev_opp; + + mutex_lock(&dev_opp_list_lock); + + /* Check for existing list for 'dev' first */ + dev_opp = _find_device_opp(dev); + if (IS_ERR(dev_opp)) { + dev_err(dev, "Failed to find dev_opp: %ld\n", PTR_ERR(dev_opp)); + goto unlock; + } + + if (IS_ERR_OR_NULL(dev_opp->regulator)) { + dev_err(dev, "%s: Doesn't have regulator set\n", __func__); + goto unlock; + } + + /* Make sure there are no concurrent readers while updating dev_opp */ + WARN_ON(!list_empty(&dev_opp->opp_list)); + + regulator_put(dev_opp->regulator); + dev_opp->regulator = ERR_PTR(-EINVAL); + + /* Try freeing device_opp if this was the last blocking resource */ + _remove_device_opp(dev_opp); + +unlock: + mutex_unlock(&dev_opp_list_lock); +} +EXPORT_SYMBOL_GPL(dev_pm_opp_put_regulator); + static bool _opp_is_supported(struct device *dev, struct device_opp *dev_opp, struct device_node *np) { diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h index 690638ef36ee5..416293b7da237 100644 --- a/drivers/base/power/opp/opp.h +++ b/drivers/base/power/opp/opp.h @@ -22,6 +22,8 @@ #include #include +struct regulator; + /* Lock to allow exclusive modification to the device and opp lists */ extern struct mutex dev_opp_list_lock; @@ -132,6 +134,7 @@ struct device_list_opp { * @supported_hw: Array of version number to support. * @supported_hw_count: Number of elements in supported_hw array. * @prop_name: A name to postfix to many DT properties, while parsing them. + * @regulator: Supply regulator * @dentry: debugfs dentry pointer of the real device directory (not links). * @dentry_name: Name of the real dentry. * @@ -159,6 +162,7 @@ struct device_opp { unsigned int *supported_hw; unsigned int supported_hw_count; const char *prop_name; + struct regulator *regulator; #ifdef CONFIG_DEBUG_FS struct dentry *dentry; diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index 95403d2ccaf56..c70a18ac9c8a7 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -60,6 +60,8 @@ int dev_pm_opp_set_supported_hw(struct device *dev, const u32 *versions, void dev_pm_opp_put_supported_hw(struct device *dev); int dev_pm_opp_set_prop_name(struct device *dev, const char *name); void dev_pm_opp_put_prop_name(struct device *dev); +int dev_pm_opp_set_regulator(struct device *dev, const char *name); +void dev_pm_opp_put_regulator(struct device *dev); #else static inline unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp) { @@ -151,6 +153,13 @@ static inline int dev_pm_opp_set_prop_name(struct device *dev, const char *name) static inline void dev_pm_opp_put_prop_name(struct device *dev) {} +static inline int dev_pm_opp_set_regulator(struct device *dev, const char *name) +{ + return -EINVAL; +} + +static inline void dev_pm_opp_put_regulator(struct device *dev) {} + #endif /* CONFIG_PM_OPP */ #if defined(CONFIG_PM_OPP) && defined(CONFIG_OF)