From patchwork Mon Apr 29 23:40:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Lechner X-Patchwork-Id: 13647869 Received: from mail-ot1-f43.google.com (mail-ot1-f43.google.com [209.85.210.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 093C4199E8B for ; Mon, 29 Apr 2024 23:40:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.43 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714434038; cv=none; b=iPWSleWx6Buu5DsSc6kfzy3zd45M+MByuCo1qD+xPvFBh9FR8DaLCnRsNZ4lemV53yPxxPmiaxZbzdM4hbAYEMNo7RM/7JZdE5hKW3z2pqvDqM0eyBgh74jtmK6HgS1a1Bgf8EL8ndkILmLAimQURE6UGURupufSqtHLOWmoArE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714434038; c=relaxed/simple; bh=9vMzN7GknLhBK91OqN5FGd7OXYyaUfOO8wINrzGG+oo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=S4GD+l3LV7WnWuETj8yPT/zveNU3XDLzN+hUsszHlJzZ2uD/4MrL/qpc8NViHvzqHgZVrfPzQKlytKMOs0qTe9kBOdLQK583XPwOVYsIcuRWxf8bm53865xtsb8CyVd616UpIa/lfNRSkG2syHS2xQwOTcoRn6ScYmK/D/Akszw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=baylibre.com; spf=pass smtp.mailfrom=baylibre.com; dkim=pass (2048-bit key) header.d=baylibre-com.20230601.gappssmtp.com header.i=@baylibre-com.20230601.gappssmtp.com header.b=OnHNl+55; arc=none smtp.client-ip=209.85.210.43 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=baylibre.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=baylibre.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=baylibre-com.20230601.gappssmtp.com header.i=@baylibre-com.20230601.gappssmtp.com header.b="OnHNl+55" Received: by mail-ot1-f43.google.com with SMTP id 46e09a7af769-6ea2375d8d0so4172198a34.0 for ; Mon, 29 Apr 2024 16:40:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20230601.gappssmtp.com; s=20230601; t=1714434035; x=1715038835; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=U0CekvxTmvga6LetnTaTS9D84AmKilMVxsoFH3MiYrM=; b=OnHNl+551AFCEQRJL0v+SJ/Cb6yUA3AiYq6YFTJTZjoP6d+jX1JTo1hyU0aAW5nwma 2H3mw+CcMSleydbQaDDxBpnETPN/4rTisJScMOZU9k94IvbfnwzLUnFddOeJhdSPmicH 2mxfu0hmXYiXsH88t2T9jI61BOvR6i55SufZnB1QrIB5FIxzdosDuffF161YjVOs8wUq hkVmMzl/zt/ysCwcHbv5YKlduevuPeYAiPaYvdKIWFhQIkoADAlgfmXi4aoMpD7KbXr8 8IdMyoOCrpFCnIjfu0+1AG9ihEB9kADlPQ6O0NKcc6F9vR4da56XwKEx8tSBuFxGBPgO FHdQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1714434035; x=1715038835; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=U0CekvxTmvga6LetnTaTS9D84AmKilMVxsoFH3MiYrM=; b=d6wYNXHZqzwSFyP4slCz18I5jULYqBcExAW0QRspiX5QUr7+9Au2Pp+w06hR62a69X /I8EPmpZL8zd1DkPsTkmPMsOoStylAEzD+c9W4k6ZLM0wU3B2mfBAYVVdoCeamT5v8yd ClAdFWfsmfHIra8fYkmImL3xk9r8cF6X6l7CVv8JtXShgd9J9dCkDV9LHFyePonEwOuI gwQJUi/gSGEVT3RfIz272Oy52dbyve1jQ7wvUrQme1cKFxKJp6m0Qw09C7279H+prk2i hFsnWUyuvv5U42L3KDlJeBuhYo9VVJmU1Bt2GrHTc8Qab/0mu9Lbp2+IV2WMe147X58N Samw== X-Forwarded-Encrypted: i=1; AJvYcCXYljwkyEAV05CIXcwmrc3fuPjbpJsE7aY1eTZnfnJKejnKzMyj4u+x7MJ3Pljn9M5rdWPdtnd5mZo6Eo05ryE0+1rNP/zyFo7F X-Gm-Message-State: AOJu0YyORSbgWyfBJNyEN5eQNC0p98GvgR+RngasSgyQCcEuP2b6JT1R B52JU+JYM9SJ9HZjiRFp5G18K0lA2fQKnGsAdiIik3Q4DPwQ0U9dhIyO0+N7NK8= X-Google-Smtp-Source: AGHT+IG3ocOUnX8fvHwyLMD+MT8XyRnapUIMPk5vg9h/GD5BQU/zEJPB811dMM2382JKTXmv4mcYHA== X-Received: by 2002:a05:6871:7aa:b0:23a:980f:1fb8 with SMTP id o42-20020a05687107aa00b0023a980f1fb8mr13141585oap.53.1714434035037; Mon, 29 Apr 2024 16:40:35 -0700 (PDT) Received: from freyr.lechnology.com (ip98-183-112-25.ok.ok.cox.net. [98.183.112.25]) by smtp.gmail.com with ESMTPSA id hp22-20020a0568709a9600b0023b58aa20afsm2144508oab.25.2024.04.29.16.40.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 29 Apr 2024 16:40:34 -0700 (PDT) From: David Lechner To: Liam Girdwood , Mark Brown , Jean Delvare , Guenter Roeck , Jonathan Cameron , Dmitry Torokhov Cc: David Lechner , Jonathan Corbet , Support Opensource , Cosmin Tanislav , Lars-Peter Clausen , Michael Hennerich , Antoniu Miclaus , Greg Kroah-Hartman , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-iio@vger.kernel.org, linux-staging@lists.linux.dev, linux-input@vger.kernel.org Subject: [PATCH v2 1/7] regulator: devres: add API for reference voltage supplies Date: Mon, 29 Apr 2024 18:40:09 -0500 Message-ID: <20240429-regulator-get-enable-get-votlage-v2-1-b1f11ab766c1@baylibre.com> X-Mailer: git-send-email 2.43.2 In-Reply-To: <20240429-regulator-get-enable-get-votlage-v2-0-b1f11ab766c1@baylibre.com> References: <20240429-regulator-get-enable-get-votlage-v2-0-b1f11ab766c1@baylibre.com> Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Mailer: b4 0.12.4 A common use case for regulators is to supply a reference voltage to an analog input or output device. This adds a new devres API to get, enable, and get the voltage in a single call. This allows eliminating boilerplate code in drivers that use reference supplies in this way. Signed-off-by: David Lechner --- v2 changes: * removed dev_err_probe() on error return * dropped optional version of the function since there is no more difference after dev_err_probe() is removed * renamed function to devm_regulator_get_enable_read_voltage() * added unwinding on error paths --- Documentation/driver-api/driver-model/devres.rst | 1 + drivers/regulator/devres.c | 59 ++++++++++++++++++++++++ include/linux/regulator/consumer.h | 7 +++ 3 files changed, 67 insertions(+) diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst index 7be8b8dd5f00..18caebad7376 100644 --- a/Documentation/driver-api/driver-model/devres.rst +++ b/Documentation/driver-api/driver-model/devres.rst @@ -433,6 +433,7 @@ REGULATOR devm_regulator_bulk_put() devm_regulator_get() devm_regulator_get_enable() + devm_regulator_get_enable_read_voltage() devm_regulator_get_enable_optional() devm_regulator_get_exclusive() devm_regulator_get_optional() diff --git a/drivers/regulator/devres.c b/drivers/regulator/devres.c index 90bb0d178885..4f290b9b559b 100644 --- a/drivers/regulator/devres.c +++ b/drivers/regulator/devres.c @@ -145,6 +145,65 @@ struct regulator *devm_regulator_get_optional(struct device *dev, } EXPORT_SYMBOL_GPL(devm_regulator_get_optional); +/** + * devm_regulator_get_enable_read_voltage - Resource managed regulator get and + * enable that returns the voltage + * @dev: device to supply + * @id: supply name or regulator ID. + * + * Get and enable regulator for duration of the device life-time. + * regulator_disable() and regulator_put() are automatically called on driver + * detach. See regulator_get_optional(), regulator_enable(), and + * regulator_get_voltage() for more information. + * + * This is a convenience function for supplies that provide a reference voltage + * where the consumer driver just needs to know the voltage and keep the + * regulator enabled. + * + * In cases where the supply is not strictly required, callers can check for + * -ENODEV error and handle it accordingly. + * + * Returns: voltage in microvolts on success, or an error code on failure. + */ +int devm_regulator_get_enable_read_voltage(struct device *dev, const char *id) +{ + struct regulator *r; + int ret; + + /* + * Since we need a real voltage, we use devm_regulator_get_optional() + * rather than getting a dummy regulator with devm_regulator_get() and + * then letting regulator_get_voltage() fail with -EINVAL. This way, the + * caller can handle the -ENODEV error code if needed instead of the + * ambiguous -EINVAL. + */ + r = devm_regulator_get_optional(dev, id); + if (IS_ERR(r)) + return PTR_ERR(r); + + ret = regulator_enable(r); + if (ret) + goto err_regulator_put; + + ret = devm_add_action_or_reset(dev, regulator_action_disable, r); + if (ret) + goto err_regulator_put; + + ret = regulator_get_voltage(r); + if (ret < 0) + goto err_release_action; + + return 0; + +err_release_action: + devm_release_action(dev, regulator_action_disable, r); +err_regulator_put: + devm_regulator_put(r); + + return ret; +} +EXPORT_SYMBOL_GPL(devm_regulator_get_enable_read_voltage); + static int devm_regulator_match(struct device *dev, void *res, void *data) { struct regulator **r = res; diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h index ed180ca419da..59d0b9a79e6e 100644 --- a/include/linux/regulator/consumer.h +++ b/include/linux/regulator/consumer.h @@ -164,6 +164,7 @@ struct regulator *__must_check devm_regulator_get_optional(struct device *dev, const char *id); int devm_regulator_get_enable(struct device *dev, const char *id); int devm_regulator_get_enable_optional(struct device *dev, const char *id); +int devm_regulator_get_enable_read_voltage(struct device *dev, const char *id); void regulator_put(struct regulator *regulator); void devm_regulator_put(struct regulator *regulator); @@ -329,6 +330,12 @@ static inline int devm_regulator_get_enable_optional(struct device *dev, return 0; } +static inline int devm_regulator_get_enable_read_voltage(struct device *dev, + const char *id) +{ + return -ENODEV; +} + static inline struct regulator *__must_check regulator_get_optional(struct device *dev, const char *id) {