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authorLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
commit3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch)
treeb767d7f6e26bc64334d3f14f8422d187239dc45d /drivers/regulator/fixed.c
downloadlinux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz
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Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe: - Fix a task_work add use-after-free with SQPOLL. The sqpoll thread could pop and complete the last request while io_req_normal_work_add() was still looking at them after the mpscq push. Use the same approach as DEFER_TASKRUN to protect from that, holding an RCU read lock across the add, and have exit wait for an RCU grace period for SQPOLL rings as well. - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED rings - Mark the source filter table as COW when cloning bpf filters, so registering another filter on the source doesn't modify the shared table in place - Initialize the task context before running the BPF loop - Requeue zcrx multishot receives stopped by a local resource - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit) * tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring: fix task_work add use-after-free with SQPOLL io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full io_uring/zcrx: requeue multishot receives stopped by a local resource io_uring: initialize task context before running the BPF loop io_uring: zero big_cqe for aux CQEs on CQE32 rings io_uring: fix free entry check for 32b CQEs on CQE32 rings io_uring: only post the dummy skip CQE on CQE_MIXED rings io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'drivers/regulator/fixed.c')
-rw-r--r--drivers/regulator/fixed.c402
1 files changed, 402 insertions, 0 deletions
diff --git a/drivers/regulator/fixed.c b/drivers/regulator/fixed.c
new file mode 100644
index 000000000..417d282dd
--- /dev/null
+++ b/drivers/regulator/fixed.c
@@ -0,0 +1,402 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * fixed.c
+ *
+ * Copyright 2008 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ *
+ * Copyright (c) 2009 Nokia Corporation
+ * Roger Quadros <ext-roger.quadros@nokia.com>
+ *
+ * This is useful for systems with mixed controllable and
+ * non-controllable regulators, as well as for allowing testing on
+ * systems with no controllable regulators.
+ */
+
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_opp.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/fixed.h>
+#include <linux/gpio/consumer.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/regulator/machine.h>
+#include <linux/clk.h>
+
+struct fixed_voltage_data {
+ struct regulator_desc desc;
+ struct regulator_dev *dev;
+
+ struct clk *enable_clock;
+ unsigned int enable_counter;
+ int performance_state;
+};
+
+struct fixed_dev_type {
+ bool has_enable_clock;
+ bool has_performance_state;
+};
+
+static int reg_clock_enable(struct regulator_dev *rdev)
+{
+ struct fixed_voltage_data *priv = rdev_get_drvdata(rdev);
+ int ret = 0;
+
+ ret = clk_prepare_enable(priv->enable_clock);
+ if (ret)
+ return ret;
+
+ priv->enable_counter++;
+
+ return ret;
+}
+
+static int reg_clock_disable(struct regulator_dev *rdev)
+{
+ struct fixed_voltage_data *priv = rdev_get_drvdata(rdev);
+
+ clk_disable_unprepare(priv->enable_clock);
+ priv->enable_counter--;
+
+ return 0;
+}
+
+static int reg_domain_enable(struct regulator_dev *rdev)
+{
+ struct fixed_voltage_data *priv = rdev_get_drvdata(rdev);
+ struct device *dev = rdev->dev.parent;
+ int ret;
+
+ ret = dev_pm_genpd_set_performance_state(dev, priv->performance_state);
+ if (ret)
+ return ret;
+
+ priv->enable_counter++;
+
+ return ret;
+}
+
+static int reg_domain_disable(struct regulator_dev *rdev)
+{
+ struct fixed_voltage_data *priv = rdev_get_drvdata(rdev);
+ struct device *dev = rdev->dev.parent;
+ int ret;
+
+ ret = dev_pm_genpd_set_performance_state(dev, 0);
+ if (ret)
+ return ret;
+
+ priv->enable_counter--;
+
+ return 0;
+}
+
+static int reg_is_enabled(struct regulator_dev *rdev)
+{
+ struct fixed_voltage_data *priv = rdev_get_drvdata(rdev);
+
+ return priv->enable_counter > 0;
+}
+
+static irqreturn_t reg_fixed_under_voltage_irq_handler(int irq, void *data)
+{
+ struct fixed_voltage_data *priv = data;
+ struct regulator_dev *rdev = priv->dev;
+
+ regulator_notifier_call_chain(rdev, REGULATOR_EVENT_UNDER_VOLTAGE,
+ NULL);
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * reg_fixed_get_irqs - Get and register the optional IRQ for fixed voltage
+ * regulator.
+ * @dev: Pointer to the device structure.
+ * @priv: Pointer to fixed_voltage_data structure containing private data.
+ *
+ * This function tries to get the IRQ from the device firmware node.
+ * If it's an optional IRQ and not found, it returns 0.
+ * Otherwise, it attempts to request the threaded IRQ.
+ *
+ * Return: 0 on success, or a negative error number on failure.
+ */
+static int reg_fixed_get_irqs(struct device *dev,
+ struct fixed_voltage_data *priv)
+{
+ int ret;
+
+ ret = fwnode_irq_get(dev_fwnode(dev), 0);
+ /* This is optional IRQ. If not found we will get -EINVAL */
+ if (ret == -EINVAL)
+ return 0;
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Failed to get IRQ\n");
+
+ ret = devm_request_threaded_irq(dev, ret, NULL,
+ reg_fixed_under_voltage_irq_handler,
+ IRQF_ONESHOT, "under-voltage", priv);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to request IRQ\n");
+
+ return 0;
+}
+
+/**
+ * of_get_fixed_voltage_config - extract fixed_voltage_config structure info
+ * @dev: device requesting for fixed_voltage_config
+ * @desc: regulator description
+ *
+ * Populates fixed_voltage_config structure by extracting data from device
+ * tree node.
+ *
+ * Return: Pointer to a populated &struct fixed_voltage_config or %NULL if
+ * memory allocation fails.
+ */
+static struct fixed_voltage_config *
+of_get_fixed_voltage_config(struct device *dev,
+ const struct regulator_desc *desc)
+{
+ struct fixed_voltage_config *config;
+ struct device_node *np = dev->of_node;
+ struct regulator_init_data *init_data;
+
+ config = devm_kzalloc(dev, sizeof(struct fixed_voltage_config),
+ GFP_KERNEL);
+ if (!config)
+ return ERR_PTR(-ENOMEM);
+
+ config->init_data = of_get_regulator_init_data(dev, dev->of_node, desc);
+ if (!config->init_data)
+ return ERR_PTR(-EINVAL);
+
+ init_data = config->init_data;
+ init_data->constraints.apply_uV = 0;
+
+ config->supply_name = init_data->constraints.name;
+ if (init_data->constraints.min_uV == init_data->constraints.max_uV) {
+ config->microvolts = init_data->constraints.min_uV;
+ } else {
+ dev_err(dev,
+ "Fixed regulator specified with variable voltages\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (init_data->constraints.boot_on)
+ config->enabled_at_boot = true;
+
+ of_property_read_u32(np, "startup-delay-us", &config->startup_delay);
+ of_property_read_u32(np, "off-on-delay-us", &config->off_on_delay);
+
+ if (of_property_present(np, "vin-supply"))
+ config->input_supply = "vin";
+
+ return config;
+}
+
+static const struct regulator_ops fixed_voltage_ops = {
+};
+
+static const struct regulator_ops fixed_voltage_clkenabled_ops = {
+ .enable = reg_clock_enable,
+ .disable = reg_clock_disable,
+ .is_enabled = reg_is_enabled,
+};
+
+static const struct regulator_ops fixed_voltage_domain_ops = {
+ .enable = reg_domain_enable,
+ .disable = reg_domain_disable,
+ .is_enabled = reg_is_enabled,
+};
+
+static int reg_fixed_voltage_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct fixed_voltage_config *config;
+ struct fixed_voltage_data *drvdata;
+ const struct fixed_dev_type *drvtype = of_device_get_match_data(dev);
+ struct regulator_config cfg = { };
+ enum gpiod_flags gflags;
+ int ret;
+
+ drvdata = devm_kzalloc(&pdev->dev, sizeof(struct fixed_voltage_data),
+ GFP_KERNEL);
+ if (!drvdata)
+ return -ENOMEM;
+
+ if (pdev->dev.of_node) {
+ config = of_get_fixed_voltage_config(&pdev->dev,
+ &drvdata->desc);
+ if (IS_ERR(config))
+ return PTR_ERR(config);
+ } else {
+ config = dev_get_platdata(&pdev->dev);
+ }
+
+ if (!config)
+ return -ENOMEM;
+
+ drvdata->desc.name = devm_kstrdup(&pdev->dev,
+ config->supply_name,
+ GFP_KERNEL);
+ if (drvdata->desc.name == NULL) {
+ dev_err(&pdev->dev, "Failed to allocate supply name\n");
+ return -ENOMEM;
+ }
+ drvdata->desc.type = REGULATOR_VOLTAGE;
+ drvdata->desc.owner = THIS_MODULE;
+
+ if (drvtype && drvtype->has_enable_clock) {
+ drvdata->desc.ops = &fixed_voltage_clkenabled_ops;
+
+ drvdata->enable_clock = devm_clk_get(dev, NULL);
+ if (IS_ERR(drvdata->enable_clock)) {
+ dev_err(dev, "Can't get enable-clock from devicetree\n");
+ return PTR_ERR(drvdata->enable_clock);
+ }
+ } else if (drvtype && drvtype->has_performance_state) {
+ drvdata->desc.ops = &fixed_voltage_domain_ops;
+
+ drvdata->performance_state = of_get_required_opp_performance_state(dev->of_node, 0);
+ if (drvdata->performance_state < 0) {
+ dev_err(dev, "Can't get performance state from devicetree\n");
+ return drvdata->performance_state;
+ }
+ } else {
+ drvdata->desc.ops = &fixed_voltage_ops;
+ }
+
+ drvdata->desc.enable_time = config->startup_delay;
+ drvdata->desc.off_on_delay = config->off_on_delay;
+
+ if (config->input_supply) {
+ drvdata->desc.supply_name = devm_kstrdup(&pdev->dev,
+ config->input_supply,
+ GFP_KERNEL);
+ if (!drvdata->desc.supply_name)
+ return -ENOMEM;
+ }
+
+ if (config->microvolts)
+ drvdata->desc.n_voltages = 1;
+
+ drvdata->desc.fixed_uV = config->microvolts;
+
+ /*
+ * The signal will be inverted by the GPIO core if flagged so in the
+ * descriptor.
+ */
+ if (config->enabled_at_boot)
+ gflags = GPIOD_OUT_HIGH;
+ else
+ gflags = GPIOD_OUT_LOW;
+
+ /*
+ * Some fixed regulators share the enable line between two
+ * regulators which makes it necessary to get a handle on the
+ * same descriptor for two different consumers. This will get
+ * the GPIO descriptor, but only the first call will initialize
+ * it so any flags such as inversion or open drain will only
+ * be set up by the first caller and assumed identical on the
+ * next caller.
+ *
+ * FIXME: find a better way to deal with this.
+ */
+ gflags |= GPIOD_FLAGS_BIT_NONEXCLUSIVE;
+
+ /*
+ * Do not use devm* here: the regulator core takes over the
+ * lifecycle management of the GPIO descriptor.
+ */
+ cfg.ena_gpiod = gpiod_get_optional(&pdev->dev, NULL, gflags);
+ if (IS_ERR(cfg.ena_gpiod))
+ return dev_err_probe(&pdev->dev, PTR_ERR(cfg.ena_gpiod),
+ "can't get GPIO\n");
+
+ cfg.dev = &pdev->dev;
+ cfg.init_data = config->init_data;
+ cfg.driver_data = drvdata;
+ cfg.of_node = pdev->dev.of_node;
+
+ drvdata->dev = devm_regulator_register(&pdev->dev, &drvdata->desc,
+ &cfg);
+ if (IS_ERR(drvdata->dev))
+ return dev_err_probe(&pdev->dev, PTR_ERR(drvdata->dev),
+ "Failed to register regulator: %ld\n",
+ PTR_ERR(drvdata->dev));
+
+ platform_set_drvdata(pdev, drvdata);
+
+ dev_dbg(&pdev->dev, "%s supplying %duV\n", drvdata->desc.name,
+ drvdata->desc.fixed_uV);
+
+ ret = reg_fixed_get_irqs(dev, drvdata);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+#if defined(CONFIG_OF)
+static const struct fixed_dev_type fixed_voltage_data = {
+ .has_enable_clock = false,
+};
+
+static const struct fixed_dev_type fixed_clkenable_data = {
+ .has_enable_clock = true,
+};
+
+static const struct fixed_dev_type fixed_domain_data = {
+ .has_performance_state = true,
+};
+
+static const struct of_device_id fixed_of_match[] = {
+ {
+ .compatible = "regulator-fixed",
+ .data = &fixed_voltage_data,
+ },
+ {
+ .compatible = "regulator-fixed-clock",
+ .data = &fixed_clkenable_data,
+ },
+ {
+ .compatible = "regulator-fixed-domain",
+ .data = &fixed_domain_data,
+ },
+ {
+ },
+};
+MODULE_DEVICE_TABLE(of, fixed_of_match);
+#endif
+
+static struct platform_driver regulator_fixed_voltage_driver = {
+ .probe = reg_fixed_voltage_probe,
+ .driver = {
+ .name = "reg-fixed-voltage",
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ .of_match_table = of_match_ptr(fixed_of_match),
+ },
+};
+
+static int __init regulator_fixed_voltage_init(void)
+{
+ return platform_driver_register(&regulator_fixed_voltage_driver);
+}
+subsys_initcall(regulator_fixed_voltage_init);
+
+static void __exit regulator_fixed_voltage_exit(void)
+{
+ platform_driver_unregister(&regulator_fixed_voltage_driver);
+}
+module_exit(regulator_fixed_voltage_exit);
+
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("Fixed voltage regulator");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:reg-fixed-voltage");