/* * 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 * * 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){	struct fixed_voltage_config *config;	struct device_node *np = dev->of_node;	const __be32 *delay;	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);	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); 	delay = of_get_property(np, "startup-delay-us", NULL);	if (delay)		config->startup_delay = be32_to_cpu(*delay); 	if (of_find_property(np, "enable-active-high", NULL))		config->enable_high = true; 	if (of_find_property(np, "gpio-open-drain", NULL))		config->gpio_is_open_drain = true; 	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; 	if (pdev->dev.of_node) {		config = of_get_fixed_voltage_config(&pdev->dev);		if (IS_ERR(config))			return PTR_ERR(config);	} else {		config = dev_get_platdata(&pdev->dev);	} 	if (!config)		return -ENOMEM; 	drvdata = devm_kzalloc(&pdev->dev, sizeof(struct fixed_voltage_data),			       GFP_KERNEL);	if (drvdata == NULL) {		dev_err(&pdev->dev, "Failed to allocate device data\n");		ret = -ENOMEM;		goto err;	} 	drvdata->desc.name = kstrdup(config->supply_name, GFP_KERNEL);	if (drvdata->desc.name == NULL) {		dev_err(&pdev->dev, "Failed to allocate supply name\n");		ret = -ENOMEM;		goto err;	}	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 = kstrdup(config->input_supply,							GFP_KERNEL);		if (!drvdata->desc.supply_name) {			dev_err(&pdev->dev,				"Failed to allocate input supply\n");			ret = -ENOMEM;			goto err_name;		}	} 	if (config->microvolts)		drvdata->desc.n_voltages = 1; 	drvdata->desc.fixed_uV = config->microvolts; 	if (config->gpio >= 0)		cfg.ena_gpio = config->gpio;	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 = regulator_register(&drvdata->desc, &cfg);	if (IS_ERR(drvdata->dev)) {		ret = PTR_ERR(drvdata->dev);		dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);		goto err_input;	} 	platform_set_drvdata(pdev, drvdata); 	dev_dbg(&pdev->dev, "%s supplying %duV\n", drvdata->desc.name,		drvdata->desc.fixed_uV); 	return 0; err_input:	kfree(drvdata->desc.supply_name);err_name:	kfree(drvdata->desc.name);err:	return ret;} static int reg_fixed_voltage_remove(struct platform_device *pdev){	struct fixed_voltage_data *drvdata = platform_get_drvdata(pdev); 	regulator_unregister(drvdata->dev);	kfree(drvdata->desc.supply_name);	kfree(drvdata->desc.name); 	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,	.remove		= reg_fixed_voltage_remove,	.driver		= {		.name		= "reg-fixed-voltage",		.owner		= THIS_MODULE,		.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");