--- /dev/null
+/*
+ * 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 program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * 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/regulator/driver.h>
+#include <linux/regulator/fixed.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/regulator/machine.h>
+
+struct fixed_voltage_data {
+ struct regulator_desc desc;
+ struct regulator_dev *dev;
+};
+
+
+/**
+ * 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, returns a pointer to the populated structure of NULL if memory
+ * alloc 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;
+
+ config->gpio = of_get_named_gpio(np, "gpio", 0);
+ /*
+ * of_get_named_gpio() currently returns ENODEV rather than
+ * EPROBE_DEFER. This code attempts to be compatible with both
+ * for now; the ENODEV check can be removed once the API is fixed.
+ * of_get_named_gpio() doesn't differentiate between a missing
+ * property (which would be fine here, since the GPIO is optional)
+ * and some other error. Patches have been posted for both issues.
+ * Once they are check in, we should replace this with:
+ * if (config->gpio < 0 && config->gpio != -ENOENT)
+ */
+ if ((config->gpio == -ENODEV) || (config->gpio == -EPROBE_DEFER))
+ return ERR_PTR(-EPROBE_DEFER);
+
+ of_property_read_u32(np, "startup-delay-us", &config->startup_delay);
+
+ config->enable_high = of_property_read_bool(np, "enable-active-high");
+ config->gpio_is_open_drain = of_property_read_bool(np,
+ "gpio-open-drain");
+
+ if (of_find_property(np, "vin-supply", NULL))
+ config->input_supply = "vin";
+
+ return config;
+}
+
+static struct regulator_ops fixed_voltage_ops = {
+};
+
+static int reg_fixed_voltage_probe(struct platform_device *pdev)
+{
+ struct fixed_voltage_config *config;
+ struct fixed_voltage_data *drvdata;
+ struct regulator_config cfg = { };
+ 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;
+ drvdata->desc.ops = &fixed_voltage_ops;
+
+ drvdata->desc.enable_time = config->startup_delay;
+
+ if (config->input_supply) {
+ drvdata->desc.supply_name = devm_kstrdup(&pdev->dev,
+ config->input_supply,
+ GFP_KERNEL);
+ if (!drvdata->desc.supply_name) {
+ dev_err(&pdev->dev,
+ "Failed to allocate input supply\n");
+ return -ENOMEM;
+ }
+ }
+
+ if (config->microvolts)
+ drvdata->desc.n_voltages = 1;
+
+ drvdata->desc.fixed_uV = config->microvolts;
+
+ if (gpio_is_valid(config->gpio)) {
+ cfg.ena_gpio = config->gpio;
+ if (pdev->dev.of_node)
+ cfg.ena_gpio_initialized = true;
+ }
+ cfg.ena_gpio_invert = !config->enable_high;
+ if (config->enabled_at_boot) {
+ if (config->enable_high)
+ cfg.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
+ else
+ cfg.ena_gpio_flags |= GPIOF_OUT_INIT_LOW;
+ } else {
+ if (config->enable_high)
+ cfg.ena_gpio_flags |= GPIOF_OUT_INIT_LOW;
+ else
+ cfg.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
+ }
+ if (config->gpio_is_open_drain)
+ cfg.ena_gpio_flags |= GPIOF_OPEN_DRAIN;
+
+ 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)) {
+ ret = PTR_ERR(drvdata->dev);
+ dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, drvdata);
+
+ dev_dbg(&pdev->dev, "%s supplying %duV\n", drvdata->desc.name,
+ drvdata->desc.fixed_uV);
+
+ return 0;
+}
+
+#if defined(CONFIG_OF)
+static const struct of_device_id fixed_of_match[] = {
+ { .compatible = "regulator-fixed", },
+ {},
+};
+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",
+ .of_match_table = of_match_ptr(fixed_of_match),
+ },
+};
+
+static int __init regulator_fixed_voltage_init(void)
+{
+ return platform_driver_register(®ulator_fixed_voltage_driver);
+}
+subsys_initcall(regulator_fixed_voltage_init);
+
+static void __exit regulator_fixed_voltage_exit(void)
+{
+ platform_driver_unregister(®ulator_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");
Code Review / kvmfornfv.git / blobdiff