/* * reg-virtual-consumer.c * * Copyright 2008 Wolfson Microelectronics PLC. * * Author: Mark Brown <broonie@opensource.wolfsonmicro.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. */ #include <linux/err.h>#include <linux/mutex.h>#include <linux/platform_device.h>#include <linux/regulator/consumer.h>#include <linux/slab.h>#include <linux/module.h> struct virtual_consumer_data {	struct mutex lock;	struct regulator *regulator;	bool enabled;	int min_uV;	int max_uV;	int min_uA;	int max_uA;	unsigned int mode;}; static void update_voltage_constraints(struct device *dev,				       struct virtual_consumer_data *data){	int ret; 	if (data->min_uV && data->max_uV	    && data->min_uV <= data->max_uV) {		dev_dbg(dev, "Requesting %d-%duV\n",			data->min_uV, data->max_uV);		ret = regulator_set_voltage(data->regulator,					data->min_uV, data->max_uV);		if (ret != 0) {			dev_err(dev,				"regulator_set_voltage() failed: %d\n", ret);			return;		}	} 	if (data->min_uV && data->max_uV && !data->enabled) {		dev_dbg(dev, "Enabling regulator\n");		ret = regulator_enable(data->regulator);		if (ret == 0)			data->enabled = true;		else			dev_err(dev, "regulator_enable() failed: %d\n",				ret);	} 	if (!(data->min_uV && data->max_uV) && data->enabled) {		dev_dbg(dev, "Disabling regulator\n");		ret = regulator_disable(data->regulator);		if (ret == 0)			data->enabled = false;		else			dev_err(dev, "regulator_disable() failed: %d\n",				ret);	}} static void update_current_limit_constraints(struct device *dev,					  struct virtual_consumer_data *data){	int ret; 	if (data->max_uA	    && data->min_uA <= data->max_uA) {		dev_dbg(dev, "Requesting %d-%duA\n",			data->min_uA, data->max_uA);		ret = regulator_set_current_limit(data->regulator,					data->min_uA, data->max_uA);		if (ret != 0) {			dev_err(dev,				"regulator_set_current_limit() failed: %d\n",				ret);			return;		}	} 	if (data->max_uA && !data->enabled) {		dev_dbg(dev, "Enabling regulator\n");		ret = regulator_enable(data->regulator);		if (ret == 0)			data->enabled = true;		else			dev_err(dev, "regulator_enable() failed: %d\n",				ret);	} 	if (!(data->min_uA && data->max_uA) && data->enabled) {		dev_dbg(dev, "Disabling regulator\n");		ret = regulator_disable(data->regulator);		if (ret == 0)			data->enabled = false;		else			dev_err(dev, "regulator_disable() failed: %d\n",				ret);	}} static ssize_t show_min_uV(struct device *dev,			   struct device_attribute *attr, char *buf){	struct virtual_consumer_data *data = dev_get_drvdata(dev);	return sprintf(buf, "%d\n", data->min_uV);} static ssize_t set_min_uV(struct device *dev, struct device_attribute *attr,			  const char *buf, size_t count){	struct virtual_consumer_data *data = dev_get_drvdata(dev);	long val; 	if (kstrtol(buf, 10, &val) != 0)		return count; 	mutex_lock(&data->lock); 	data->min_uV = val;	update_voltage_constraints(dev, data); 	mutex_unlock(&data->lock); 	return count;} static ssize_t show_max_uV(struct device *dev,			   struct device_attribute *attr, char *buf){	struct virtual_consumer_data *data = dev_get_drvdata(dev);	return sprintf(buf, "%d\n", data->max_uV);} static ssize_t set_max_uV(struct device *dev, struct device_attribute *attr,			  const char *buf, size_t count){	struct virtual_consumer_data *data = dev_get_drvdata(dev);	long val; 	if (kstrtol(buf, 10, &val) != 0)		return count; 	mutex_lock(&data->lock); 	data->max_uV = val;	update_voltage_constraints(dev, data); 	mutex_unlock(&data->lock); 	return count;} static ssize_t show_min_uA(struct device *dev,			   struct device_attribute *attr, char *buf){	struct virtual_consumer_data *data = dev_get_drvdata(dev);	return sprintf(buf, "%d\n", data->min_uA);} static ssize_t set_min_uA(struct device *dev, struct device_attribute *attr,			  const char *buf, size_t count){	struct virtual_consumer_data *data = dev_get_drvdata(dev);	long val; 	if (kstrtol(buf, 10, &val) != 0)		return count; 	mutex_lock(&data->lock); 	data->min_uA = val;	update_current_limit_constraints(dev, data); 	mutex_unlock(&data->lock); 	return count;} static ssize_t show_max_uA(struct device *dev,			   struct device_attribute *attr, char *buf){	struct virtual_consumer_data *data = dev_get_drvdata(dev);	return sprintf(buf, "%d\n", data->max_uA);} static ssize_t set_max_uA(struct device *dev, struct device_attribute *attr,			  const char *buf, size_t count){	struct virtual_consumer_data *data = dev_get_drvdata(dev);	long val; 	if (kstrtol(buf, 10, &val) != 0)		return count; 	mutex_lock(&data->lock); 	data->max_uA = val;	update_current_limit_constraints(dev, data); 	mutex_unlock(&data->lock); 	return count;} static ssize_t show_mode(struct device *dev,			 struct device_attribute *attr, char *buf){	struct virtual_consumer_data *data = dev_get_drvdata(dev); 	switch (data->mode) {	case REGULATOR_MODE_FAST:		return sprintf(buf, "fast\n");	case REGULATOR_MODE_NORMAL:		return sprintf(buf, "normal\n");	case REGULATOR_MODE_IDLE:		return sprintf(buf, "idle\n");	case REGULATOR_MODE_STANDBY:		return sprintf(buf, "standby\n");	default:		return sprintf(buf, "unknown\n");	}} static ssize_t set_mode(struct device *dev, struct device_attribute *attr,			const char *buf, size_t count){	struct virtual_consumer_data *data = dev_get_drvdata(dev);	unsigned int mode;	int ret; 	/*	 * sysfs_streq() doesn't need the \n's, but we add them so the strings	 * will be shared with show_mode(), above.	 */	if (sysfs_streq(buf, "fast\n"))		mode = REGULATOR_MODE_FAST;	else if (sysfs_streq(buf, "normal\n"))		mode = REGULATOR_MODE_NORMAL;	else if (sysfs_streq(buf, "idle\n"))		mode = REGULATOR_MODE_IDLE;	else if (sysfs_streq(buf, "standby\n"))		mode = REGULATOR_MODE_STANDBY;	else {		dev_err(dev, "Configuring invalid mode\n");		return count;	} 	mutex_lock(&data->lock);	ret = regulator_set_mode(data->regulator, mode);	if (ret == 0)		data->mode = mode;	else		dev_err(dev, "Failed to configure mode: %d\n", ret);	mutex_unlock(&data->lock); 	return count;} static DEVICE_ATTR(min_microvolts, 0666, show_min_uV, set_min_uV);static DEVICE_ATTR(max_microvolts, 0666, show_max_uV, set_max_uV);static DEVICE_ATTR(min_microamps, 0666, show_min_uA, set_min_uA);static DEVICE_ATTR(max_microamps, 0666, show_max_uA, set_max_uA);static DEVICE_ATTR(mode, 0666, show_mode, set_mode); static struct attribute *regulator_virtual_attributes[] = {	&dev_attr_min_microvolts.attr,	&dev_attr_max_microvolts.attr,	&dev_attr_min_microamps.attr,	&dev_attr_max_microamps.attr,	&dev_attr_mode.attr,	NULL}; static const struct attribute_group regulator_virtual_attr_group = {	.attrs	= regulator_virtual_attributes,}; static int regulator_virtual_probe(struct platform_device *pdev){	char *reg_id = dev_get_platdata(&pdev->dev);	struct virtual_consumer_data *drvdata;	int ret; 	drvdata = devm_kzalloc(&pdev->dev, sizeof(struct virtual_consumer_data),			       GFP_KERNEL);	if (drvdata == NULL)		return -ENOMEM; 	mutex_init(&drvdata->lock); 	drvdata->regulator = devm_regulator_get(&pdev->dev, reg_id);	if (IS_ERR(drvdata->regulator)) {		ret = PTR_ERR(drvdata->regulator);		dev_err(&pdev->dev, "Failed to obtain supply '%s': %d\n",			reg_id, ret);		return ret;	} 	ret = sysfs_create_group(&pdev->dev.kobj,				 &regulator_virtual_attr_group);	if (ret != 0) {		dev_err(&pdev->dev,			"Failed to create attribute group: %d\n", ret);		return ret;	} 	drvdata->mode = regulator_get_mode(drvdata->regulator); 	platform_set_drvdata(pdev, drvdata); 	return 0;} static int regulator_virtual_remove(struct platform_device *pdev){	struct virtual_consumer_data *drvdata = platform_get_drvdata(pdev); 	sysfs_remove_group(&pdev->dev.kobj, &regulator_virtual_attr_group); 	if (drvdata->enabled)		regulator_disable(drvdata->regulator); 	return 0;} static struct platform_driver regulator_virtual_consumer_driver = {	.probe		= regulator_virtual_probe,	.remove		= regulator_virtual_remove,	.driver		= {		.name		= "reg-virt-consumer",		.owner		= THIS_MODULE,	},}; module_platform_driver(regulator_virtual_consumer_driver); MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");MODULE_DESCRIPTION("Virtual regulator consumer");MODULE_LICENSE("GPL");MODULE_ALIAS("platform:reg-virt-consumer");