From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 428F31946DA; Wed, 27 May 2026 00:02:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779840154; cv=none; b=cW+Jx2lKmwD5G0x0MZUXj/2ESE4WDp3EVKmFcP2PCltWr3OQtsdHbAlRc/7zLSICjD+gjV4cQJYfHKBiLjRF0Tc/f0z9l60KCA/fTcd91JRnyZxx1MBLVeC3AreoexPOToje90KYJLahqfQ7xU/yx9qqnPgMEZr31ueblSsBXCQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779840154; c=relaxed/simple; bh=t7znY4VIaXJRFN+3es/fkU/NyIevyYaFTBMNWJ0UOWs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=FpOcPZmPj9+aJ2QI+czAapPsshdVwcuwe4+m/NVRvd9OPEW8izrs4Rqxy+aQyAb8HB0Rai1qKmXgTjJk0HzvYqKhrFU9yU2n+pSwMNzxmO8dOk4LjQvol7ZbbnulivNRkCHLDaD0+MaxfWn2WUpYKj8dy8TpvN3cPq7GT5QNGMs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=A6jIJSbU; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="A6jIJSbU" Received: by smtp.kernel.org (Postfix) with ESMTPS id 30346C2BCC4; Wed, 27 May 2026 00:02:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779840152; bh=t7znY4VIaXJRFN+3es/fkU/NyIevyYaFTBMNWJ0UOWs=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=A6jIJSbUKX9kzsrBICRUVjm6WA1JbxOzrGimvrb/SKk5JOV9qU5KRoRNrqNiPCbgl gughqwN9LLaCtAxbKWfy8tjhzpRTFB6JeQoHgxJki3HKlaS3dRxtTdhb6L6iqVh+iR 1xFKuwCnzpK2AqXLiEcrSs78vFCPcnd57fxHBw4Z2di8HeEqZROId5z5bD/qnpXmEq H/S5DpZ+KVHCDLXzJTKLKnq9CdLkG7ewP1fQqsLeQa4mnkPHfluhNUcNU8ZunvKmT9 o7XQLEdcez3ZYeT6fcOFRhkgVzg33pe+Grg72z2UTe1NhkL0ED++E8JFkqxB1h4Vo3 +jobilzunoxGg== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C24ECD5BDE; Wed, 27 May 2026 00:02:32 +0000 (UTC) From: Amit Sunil Dhamne via B4 Relay Date: Wed, 27 May 2026 00:02:25 +0000 Subject: [PATCH v2 1/2] power: supply: Add helpers to get and put arrays of power supply handles Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260527-batt-status-v2-1-4282985165f3@google.com> References: <20260527-batt-status-v2-0-4282985165f3@google.com> In-Reply-To: <20260527-batt-status-v2-0-4282985165f3@google.com> To: Sebastian Reichel , Badhri Jagan Sridharan , Heikki Krogerus , Greg Kroah-Hartman , Hans de Goede , Krzysztof Kozlowski , Marek Szyprowski , Sebastian Krzyszkowiak , Purism Kernel Team Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, =?utf-8?q?Andr=C3=A9_Draszik?= , Tudor Ambarus , Peter Griffin , RD Babiera , Kyle Tso , Amit Sunil Dhamne X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1779840151; l=5925; i=amitsd@google.com; s=20241031; h=from:subject:message-id; bh=ijjk2ySMN0dL36fe0OTjSfQADrJgWHjO1SJEZMi/CKY=; b=z2ksABg47kx5ufLiDUjWcv7ibc5t+tO8aEyiWgsPEbXTrAe1ZcTVjXv+QJwGgTDnf0x5u8Bvg TPjdPmmxmblBfo0/4sFYAQ1IW2FA2K+gqs9oE7zUtTsH5emfOlMK55B X-Developer-Key: i=amitsd@google.com; a=ed25519; pk=wD+XZSST4dmnNZf62/lqJpLm7fiyT8iv462zmQ3H6bI= X-Endpoint-Received: by B4 Relay for amitsd@google.com/20241031 with auth_id=262 X-Original-From: Amit Sunil Dhamne Reply-To: amitsd@google.com From: Amit Sunil Dhamne Add power_supply_get_battery_all() to allow drivers to obtain a list of registered battery type power supply references in the system. Also add power_supply_put_array() to release references to the power supplies when no longer needed. Signed-off-by: Amit Sunil Dhamne --- drivers/power/supply/power_supply_core.c | 137 +++++++++++++++++++++++++++++++ include/linux/power_supply.h | 12 +++ 2 files changed, 149 insertions(+) diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c index a446d3d086fc..04e5c1083e8f 100644 --- a/drivers/power/supply/power_supply_core.c +++ b/drivers/power/supply/power_supply_core.c @@ -482,6 +482,127 @@ struct power_supply *power_supply_get_by_name(const char *name) } EXPORT_SYMBOL_GPL(power_supply_get_by_name); +static int __power_supply_get_num_battery(struct power_supply *epsy, void *data) +{ + int *count = data; + + if (epsy->desc->type == POWER_SUPPLY_TYPE_BATTERY) + (*count)++; + + return 0; +} + +static int power_supply_get_num_battery(struct device *dev) +{ + int ret, count = 0; + + ret = power_supply_for_each_psy(&count, __power_supply_get_num_battery); + + dev_dbg(dev, "%s: count: %d ret %d\n", __func__, count, ret); + + if (ret) + return ret; + + return count; +} + +struct psy_get_supplies_data { + int cnt; + int size; + struct power_supply **psys; +}; + +static int __power_supply_populate_battery_array(struct power_supply *epsy, + void *_data) +{ + struct psy_get_supplies_data *data = _data; + + if (epsy->desc->type == POWER_SUPPLY_TYPE_BATTERY) { + if (data->size <= data->cnt) + return -EOVERFLOW; + + get_device(&epsy->dev); + data->psys[data->cnt] = epsy; + atomic_inc(&epsy->use_cnt); + data->cnt++; + } + + return 0; +} + +static int power_supply_populate_battery_array(struct device *dev, int size, + struct power_supply **batteries) +{ + int ret; + + struct psy_get_supplies_data data = { + .cnt = 0, + .size = size, + .psys = batteries, + }; + + ret = power_supply_for_each_psy(&data, __power_supply_populate_battery_array); + + dev_dbg(dev, "%s Found %d batteries with array size %d ret %d\n", + __func__, data.cnt, data.size, ret); + + if (ret < 0) { + power_supply_put_array(batteries, data.cnt); + return ret; + } + + return data.cnt; +} + +/** + * power_supply_get_battery_all() - Fetches references to all battery type power + * supplies. + * @dev: Pointer to device requesting the power supply refs. + * @psys: Pointer to an array of power supply refs. + * + * Helper function to get handles to all battery type power supplies. + * If acquiring a ref to a power supply fails, then the search for battery + * type power supplies will abort and the acquired power supply references will + * be released. + * + * Return: Indicates the number of battery type power supplies returned on + * success or a negative error code on failure. + * + * The caller should invoke power_supply_put_array() on the returned array + * of psy refs and free the array returned by this function using kfree() + * after use. + */ +int __must_check power_supply_get_battery_all(struct device *dev, + struct power_supply ***psys) +{ + int ret; + + if (!psys) + return -EINVAL; + + ret = power_supply_get_num_battery(dev); + if (ret < 0) + return ret; + + if (!ret) { + *psys = NULL; + return 0; + } + + *psys = kzalloc_objs(**psys, ret); + if (!*psys) + return -ENOMEM; + + ret = power_supply_populate_battery_array(dev, ret, *psys); + if (ret <= 0) { + kfree(*psys); + *psys = NULL; + } + + return ret; +} +EXPORT_SYMBOL_GPL(power_supply_get_battery_all); + /** * power_supply_put() - Drop reference obtained with power_supply_get_by_name * @psy: Reference to put @@ -496,6 +617,22 @@ void power_supply_put(struct power_supply *psy) } EXPORT_SYMBOL_GPL(power_supply_put); +/** + * power_supply_put_array() - Drop references to an array of power supplies. + * @psys: Array of power supply references to put. + * @count: Number of elements in the array. + */ +void power_supply_put_array(struct power_supply **psys, int count) +{ + int i; + + for (i = 0; i < count; i++) { + if (psys[i]) + power_supply_put(psys[i]); + } +} +EXPORT_SYMBOL_GPL(power_supply_put_array); + static int power_supply_match_device_fwnode(struct device *dev, const void *data) { return dev->parent && dev_fwnode(dev->parent) == data; diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h index 7a5e4c3242a0..026412164a88 100644 --- a/include/linux/power_supply.h +++ b/include/linux/power_supply.h @@ -806,11 +806,23 @@ extern int power_supply_reg_notifier(struct notifier_block *nb); extern void power_supply_unreg_notifier(struct notifier_block *nb); #if IS_ENABLED(CONFIG_POWER_SUPPLY) extern struct power_supply *power_supply_get_by_name(const char *name); +extern int __must_check power_supply_get_battery_all(struct device *dev, + struct power_supply ***psys); +extern void power_supply_put_array(struct power_supply **psys, int count); extern void power_supply_put(struct power_supply *psy); #else static inline void power_supply_put(struct power_supply *psy) {} static inline struct power_supply *power_supply_get_by_name(const char *name) { return NULL; } +static inline int __must_check power_supply_get_battery_all(struct device *dev, + struct power_supply ***psys) +{ + if (psys) + *psys = NULL; + return 0; +} + +static inline void power_supply_put_array(struct power_supply **psys, int count) {} #endif extern struct power_supply *power_supply_get_by_reference(struct fwnode_handle *fwnode, const char *property); -- 2.54.0.746.g67dd491aae-goog