drivers/regulator/gpio-regulator.c - kernel/mindspeed - Git at Google

 /*
  * gpio-regulator.c
  *
  * Copyright 2011 Heiko Stuebner <heiko@sntech.de>
  *
  * based on 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/machine.h>
 #include <linux/regulator/gpio-regulator.h>
 #include <linux/gpio.h>
 #include <linux/delay.h>
 #include <linux/slab.h>

 struct gpio_regulator_data {
 	struct regulator_desc desc;
 	struct regulator_dev *dev;

 	int enable_gpio;
 	bool enable_high;
 	bool is_enabled;
 	unsigned startup_delay;

 	struct gpio *gpios;
 	int nr_gpios;

 	struct gpio_regulator_state *states;
 	int nr_states;

 	int state;
 };

 static int gpio_regulator_is_enabled(struct regulator_dev *dev)
 {
 	struct gpio_regulator_data *data = rdev_get_drvdata(dev);

 	return data->is_enabled;
 }

 static int gpio_regulator_enable(struct regulator_dev *dev)
 {
 	struct gpio_regulator_data *data = rdev_get_drvdata(dev);

 	if (gpio_is_valid(data->enable_gpio)) {
 		gpio_set_value_cansleep(data->enable_gpio, data->enable_high);
 		data->is_enabled = true;
 	}

 	return 0;
 }

 static int gpio_regulator_disable(struct regulator_dev *dev)
 {
 	struct gpio_regulator_data *data = rdev_get_drvdata(dev);

 	if (gpio_is_valid(data->enable_gpio)) {
 		gpio_set_value_cansleep(data->enable_gpio, !data->enable_high);
 		data->is_enabled = false;
 	}

 	return 0;
 }

 static int gpio_regulator_enable_time(struct regulator_dev *dev)
 {
 	struct gpio_regulator_data *data = rdev_get_drvdata(dev);

 	return data->startup_delay;
 }

 static int gpio_regulator_get_value(struct regulator_dev *dev)
 {
 	struct gpio_regulator_data *data = rdev_get_drvdata(dev);
 	int ptr;

 	for (ptr = 0; ptr < data->nr_states; ptr++)
 		if (data->states[ptr].gpios == data->state)
 			return data->states[ptr].value;

 	return -EINVAL;
 }

 static int gpio_regulator_set_value(struct regulator_dev *dev,
 					int min, int max)
 {
 	struct gpio_regulator_data *data = rdev_get_drvdata(dev);
 	int ptr, target, state;

 	target = -1;
 	for (ptr = 0; ptr < data->nr_states; ptr++)
 		if (data->states[ptr].value >= min &&
 		    data->states[ptr].value <= max)
 			target = data->states[ptr].gpios;

 	if (target < 0)
 		return -EINVAL;

 	for (ptr = 0; ptr < data->nr_gpios; ptr++) {
 		state = (target & (1 << ptr)) >> ptr;
 		gpio_set_value(data->gpios[ptr].gpio, state);
 	}
 	data->state = target;

 	return 0;
 }

 static int gpio_regulator_set_voltage(struct regulator_dev *dev,
 					int min_uV, int max_uV,
 					unsigned *selector)
 {
 	return gpio_regulator_set_value(dev, min_uV, max_uV);
 }

 static int gpio_regulator_list_voltage(struct regulator_dev *dev,
 				      unsigned selector)
 {
 	struct gpio_regulator_data *data = rdev_get_drvdata(dev);

 	if (selector >= data->nr_states)
 		return -EINVAL;

 	return data->states[selector].value;
 }

 static int gpio_regulator_set_current_limit(struct regulator_dev *dev,
 					int min_uA, int max_uA)
 {
 	return gpio_regulator_set_value(dev, min_uA, max_uA);
 }

 static struct regulator_ops gpio_regulator_voltage_ops = {
 	.is_enabled = gpio_regulator_is_enabled,
 	.enable = gpio_regulator_enable,
 	.disable = gpio_regulator_disable,
 	.enable_time = gpio_regulator_enable_time,
 	.get_voltage = gpio_regulator_get_value,
 	.set_voltage = gpio_regulator_set_voltage,
 	.list_voltage = gpio_regulator_list_voltage,
 };

 static struct regulator_ops gpio_regulator_current_ops = {
 	.is_enabled = gpio_regulator_is_enabled,
 	.enable = gpio_regulator_enable,
 	.disable = gpio_regulator_disable,
 	.enable_time = gpio_regulator_enable_time,
 	.get_current_limit = gpio_regulator_get_value,
 	.set_current_limit = gpio_regulator_set_current_limit,
 };

 static int __devinit gpio_regulator_probe(struct platform_device *pdev)
 {
 	struct gpio_regulator_config *config = pdev->dev.platform_data;
 	struct gpio_regulator_data *drvdata;
 	int ptr, ret, state;

 	drvdata = kzalloc(sizeof(struct gpio_regulator_data), GFP_KERNEL);
 	if (drvdata == NULL) {
 		dev_err(&pdev->dev, "Failed to allocate device data\n");
 		return -ENOMEM;
 	}

 	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->gpios = kmemdup(config->gpios,
 				 config->nr_gpios * sizeof(struct gpio),
 				 GFP_KERNEL);
 	if (drvdata->gpios == NULL) {
 		dev_err(&pdev->dev, "Failed to allocate gpio data\n");
 		ret = -ENOMEM;
 		goto err_name;
 	}

 	drvdata->states = kmemdup(config->states,
 				  config->nr_states *
 					 sizeof(struct gpio_regulator_state),
 				  GFP_KERNEL);
 	if (drvdata->states == NULL) {
 		dev_err(&pdev->dev, "Failed to allocate state data\n");
 		ret = -ENOMEM;
 		goto err_memgpio;
 	}
 	drvdata->nr_states = config->nr_states;

 	drvdata->desc.owner = THIS_MODULE;

 	/* handle regulator type*/
 	switch (config->type) {
 	case REGULATOR_VOLTAGE:
 		drvdata->desc.type = REGULATOR_VOLTAGE;
 		drvdata->desc.ops = &gpio_regulator_voltage_ops;
 		drvdata->desc.n_voltages = config->nr_states;
 		break;
 	case REGULATOR_CURRENT:
 		drvdata->desc.type = REGULATOR_CURRENT;
 		drvdata->desc.ops = &gpio_regulator_current_ops;
 		break;
 	default:
 		dev_err(&pdev->dev, "No regulator type set\n");
 		ret = -EINVAL;
 		goto err_memgpio;
 		break;
 	}

 	drvdata->enable_gpio = config->enable_gpio;
 	drvdata->startup_delay = config->startup_delay;

 	if (gpio_is_valid(config->enable_gpio)) {
 		drvdata->enable_high = config->enable_high;

 		ret = gpio_request(config->enable_gpio, config->supply_name);
 		if (ret) {
 			dev_err(&pdev->dev,
 			   "Could not obtain regulator enable GPIO %d: %d\n",
 						config->enable_gpio, ret);
 			goto err_memstate;
 		}

 		/* set output direction without changing state
 		 * to prevent glitch
 		 */
 		if (config->enabled_at_boot) {
 			drvdata->is_enabled = true;
 			ret = gpio_direction_output(config->enable_gpio,
 						    config->enable_high);
 		} else {
 			drvdata->is_enabled = false;
 			ret = gpio_direction_output(config->enable_gpio,
 						    !config->enable_high);
 		}

 		if (ret) {
 			dev_err(&pdev->dev,
 			   "Could not configure regulator enable GPIO %d direction: %d\n",
 						config->enable_gpio, ret);
 			goto err_enablegpio;
 		}
 	} else {
 		/* Regulator without GPIO control is considered
 		 * always enabled
 		 */
 		drvdata->is_enabled = true;
 	}

 	drvdata->nr_gpios = config->nr_gpios;
 	ret = gpio_request_array(drvdata->gpios, drvdata->nr_gpios);
 	if (ret) {
 		dev_err(&pdev->dev,
 		   "Could not obtain regulator setting GPIOs: %d\n", ret);
 		goto err_enablegpio;
 	}

 	/* build initial state from gpio init data. */
 	state = 0;
 	for (ptr = 0; ptr < drvdata->nr_gpios; ptr++) {
 		if (config->gpios[ptr].flags & GPIOF_OUT_INIT_HIGH)
 			state |= (1 << ptr);
 	}
 	drvdata->state = state;

 	drvdata->dev = regulator_register(&drvdata->desc, &pdev->dev,
 					  config->init_data, drvdata);
 	if (IS_ERR(drvdata->dev)) {
 		ret = PTR_ERR(drvdata->dev);
 		dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
 		goto err_stategpio;
 	}

 	platform_set_drvdata(pdev, drvdata);

 	return 0;

 err_stategpio:
 	gpio_free_array(drvdata->gpios, drvdata->nr_gpios);
 err_enablegpio:
 	if (gpio_is_valid(config->enable_gpio))
 		gpio_free(config->enable_gpio);
 err_memstate:
 	kfree(drvdata->states);
 err_memgpio:
 	kfree(drvdata->gpios);
 err_name:
 	kfree(drvdata->desc.name);
 err:
 	kfree(drvdata);
 	return ret;
 }

 static int __devexit gpio_regulator_remove(struct platform_device *pdev)
 {
 	struct gpio_regulator_data *drvdata = platform_get_drvdata(pdev);

 	regulator_unregister(drvdata->dev);

 	gpio_free_array(drvdata->gpios, drvdata->nr_gpios);

 	kfree(drvdata->states);
 	kfree(drvdata->gpios);

 	if (gpio_is_valid(drvdata->enable_gpio))
 		gpio_free(drvdata->enable_gpio);

 	kfree(drvdata->desc.name);
 	kfree(drvdata);

 	return 0;
 }

 static struct platform_driver gpio_regulator_driver = {
 	.probe		= gpio_regulator_probe,
 	.remove		= __devexit_p(gpio_regulator_remove),
 	.driver		= {
 		.name		= "gpio-regulator",
 		.owner		= THIS_MODULE,
 	},
 };

 static int __init gpio_regulator_init(void)
 {
 	return platform_driver_register(&gpio_regulator_driver);
 }
 subsys_initcall(gpio_regulator_init);

 static void __exit gpio_regulator_exit(void)
 {
 	platform_driver_unregister(&gpio_regulator_driver);
 }
 module_exit(gpio_regulator_exit);

 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
 MODULE_DESCRIPTION("gpio voltage regulator");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:gpio-regulator");
	/*
	* gpio-regulator.c
	*
	* Copyright 2011 Heiko Stuebner <heiko@sntech.de>
	*
	* based on 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/machine.h>
	#include <linux/regulator/gpio-regulator.h>
	#include <linux/gpio.h>
	#include <linux/delay.h>
	#include <linux/slab.h>

	struct gpio_regulator_data {
	struct regulator_desc desc;
	struct regulator_dev *dev;

	int enable_gpio;
	bool enable_high;
	bool is_enabled;
	unsigned startup_delay;

	struct gpio *gpios;
	int nr_gpios;

	struct gpio_regulator_state *states;
	int nr_states;

	int state;
	};

	static int gpio_regulator_is_enabled(struct regulator_dev *dev)
	{
	struct gpio_regulator_data *data = rdev_get_drvdata(dev);

	return data->is_enabled;
	}

	static int gpio_regulator_enable(struct regulator_dev *dev)
	{
	struct gpio_regulator_data *data = rdev_get_drvdata(dev);

	if (gpio_is_valid(data->enable_gpio)) {
	gpio_set_value_cansleep(data->enable_gpio, data->enable_high);
	data->is_enabled = true;
	}

	return 0;
	}

	static int gpio_regulator_disable(struct regulator_dev *dev)
	{
	struct gpio_regulator_data *data = rdev_get_drvdata(dev);

	if (gpio_is_valid(data->enable_gpio)) {
	gpio_set_value_cansleep(data->enable_gpio, !data->enable_high);
	data->is_enabled = false;
	}

	return 0;
	}

	static int gpio_regulator_enable_time(struct regulator_dev *dev)
	{
	struct gpio_regulator_data *data = rdev_get_drvdata(dev);

	return data->startup_delay;
	}

	static int gpio_regulator_get_value(struct regulator_dev *dev)
	{
	struct gpio_regulator_data *data = rdev_get_drvdata(dev);
	int ptr;

	for (ptr = 0; ptr < data->nr_states; ptr++)
	if (data->states[ptr].gpios == data->state)
	return data->states[ptr].value;

	return -EINVAL;
	}

	static int gpio_regulator_set_value(struct regulator_dev *dev,
	int min, int max)
	{
	struct gpio_regulator_data *data = rdev_get_drvdata(dev);
	int ptr, target, state;

	target = -1;
	for (ptr = 0; ptr < data->nr_states; ptr++)
	if (data->states[ptr].value >= min &&
	data->states[ptr].value <= max)
	target = data->states[ptr].gpios;

	if (target < 0)
	return -EINVAL;

	for (ptr = 0; ptr < data->nr_gpios; ptr++) {
	state = (target & (1 << ptr)) >> ptr;
	gpio_set_value(data->gpios[ptr].gpio, state);
	}
	data->state = target;

	return 0;
	}

	static int gpio_regulator_set_voltage(struct regulator_dev *dev,
	int min_uV, int max_uV,
	unsigned *selector)
	{
	return gpio_regulator_set_value(dev, min_uV, max_uV);
	}

	static int gpio_regulator_list_voltage(struct regulator_dev *dev,
	unsigned selector)
	{
	struct gpio_regulator_data *data = rdev_get_drvdata(dev);

	if (selector >= data->nr_states)
	return -EINVAL;

	return data->states[selector].value;
	}

	static int gpio_regulator_set_current_limit(struct regulator_dev *dev,
	int min_uA, int max_uA)
	{
	return gpio_regulator_set_value(dev, min_uA, max_uA);
	}

	static struct regulator_ops gpio_regulator_voltage_ops = {
	.is_enabled = gpio_regulator_is_enabled,
	.enable = gpio_regulator_enable,
	.disable = gpio_regulator_disable,
	.enable_time = gpio_regulator_enable_time,
	.get_voltage = gpio_regulator_get_value,
	.set_voltage = gpio_regulator_set_voltage,
	.list_voltage = gpio_regulator_list_voltage,
	};

	static struct regulator_ops gpio_regulator_current_ops = {
	.is_enabled = gpio_regulator_is_enabled,
	.enable = gpio_regulator_enable,
	.disable = gpio_regulator_disable,
	.enable_time = gpio_regulator_enable_time,
	.get_current_limit = gpio_regulator_get_value,
	.set_current_limit = gpio_regulator_set_current_limit,
	};

	static int __devinit gpio_regulator_probe(struct platform_device *pdev)
	{
	struct gpio_regulator_config *config = pdev->dev.platform_data;
	struct gpio_regulator_data *drvdata;
	int ptr, ret, state;

	drvdata = kzalloc(sizeof(struct gpio_regulator_data), GFP_KERNEL);
	if (drvdata == NULL) {
	dev_err(&pdev->dev, "Failed to allocate device data\n");
	return -ENOMEM;
	}

	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->gpios = kmemdup(config->gpios,
	config->nr_gpios * sizeof(struct gpio),
	GFP_KERNEL);
	if (drvdata->gpios == NULL) {
	dev_err(&pdev->dev, "Failed to allocate gpio data\n");
	ret = -ENOMEM;
	goto err_name;
	}

	drvdata->states = kmemdup(config->states,
	config->nr_states *
	sizeof(struct gpio_regulator_state),
	GFP_KERNEL);
	if (drvdata->states == NULL) {
	dev_err(&pdev->dev, "Failed to allocate state data\n");
	ret = -ENOMEM;
	goto err_memgpio;
	}
	drvdata->nr_states = config->nr_states;

	drvdata->desc.owner = THIS_MODULE;

	/* handle regulator type*/
	switch (config->type) {
	case REGULATOR_VOLTAGE:
	drvdata->desc.type = REGULATOR_VOLTAGE;
	drvdata->desc.ops = &gpio_regulator_voltage_ops;
	drvdata->desc.n_voltages = config->nr_states;
	break;
	case REGULATOR_CURRENT:
	drvdata->desc.type = REGULATOR_CURRENT;
	drvdata->desc.ops = &gpio_regulator_current_ops;
	break;
	default:
	dev_err(&pdev->dev, "No regulator type set\n");
	ret = -EINVAL;
	goto err_memgpio;
	break;
	}

	drvdata->enable_gpio = config->enable_gpio;
	drvdata->startup_delay = config->startup_delay;

	if (gpio_is_valid(config->enable_gpio)) {
	drvdata->enable_high = config->enable_high;

	ret = gpio_request(config->enable_gpio, config->supply_name);
	if (ret) {
	dev_err(&pdev->dev,
	"Could not obtain regulator enable GPIO %d: %d\n",
	config->enable_gpio, ret);
	goto err_memstate;
	}

	/* set output direction without changing state
	* to prevent glitch
	*/
	if (config->enabled_at_boot) {
	drvdata->is_enabled = true;
	ret = gpio_direction_output(config->enable_gpio,
	config->enable_high);
	} else {
	drvdata->is_enabled = false;
	ret = gpio_direction_output(config->enable_gpio,
	!config->enable_high);
	}

	if (ret) {
	dev_err(&pdev->dev,
	"Could not configure regulator enable GPIO %d direction: %d\n",
	config->enable_gpio, ret);
	goto err_enablegpio;
	}
	} else {
	/* Regulator without GPIO control is considered
	* always enabled
	*/
	drvdata->is_enabled = true;
	}

	drvdata->nr_gpios = config->nr_gpios;
	ret = gpio_request_array(drvdata->gpios, drvdata->nr_gpios);
	if (ret) {
	dev_err(&pdev->dev,
	"Could not obtain regulator setting GPIOs: %d\n", ret);
	goto err_enablegpio;
	}

	/* build initial state from gpio init data. */
	state = 0;
	for (ptr = 0; ptr < drvdata->nr_gpios; ptr++) {
	if (config->gpios[ptr].flags & GPIOF_OUT_INIT_HIGH)
	state \|= (1 << ptr);
	}
	drvdata->state = state;

	drvdata->dev = regulator_register(&drvdata->desc, &pdev->dev,
	config->init_data, drvdata);
	if (IS_ERR(drvdata->dev)) {
	ret = PTR_ERR(drvdata->dev);
	dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
	goto err_stategpio;
	}

	platform_set_drvdata(pdev, drvdata);

	return 0;

	err_stategpio:
	gpio_free_array(drvdata->gpios, drvdata->nr_gpios);
	err_enablegpio:
	if (gpio_is_valid(config->enable_gpio))
	gpio_free(config->enable_gpio);
	err_memstate:
	kfree(drvdata->states);
	err_memgpio:
	kfree(drvdata->gpios);
	err_name:
	kfree(drvdata->desc.name);
	err:
	kfree(drvdata);
	return ret;
	}

	static int __devexit gpio_regulator_remove(struct platform_device *pdev)
	{
	struct gpio_regulator_data *drvdata = platform_get_drvdata(pdev);

	regulator_unregister(drvdata->dev);

	gpio_free_array(drvdata->gpios, drvdata->nr_gpios);

	kfree(drvdata->states);
	kfree(drvdata->gpios);

	if (gpio_is_valid(drvdata->enable_gpio))
	gpio_free(drvdata->enable_gpio);

	kfree(drvdata->desc.name);
	kfree(drvdata);

	return 0;
	}

	static struct platform_driver gpio_regulator_driver = {
	.probe = gpio_regulator_probe,
	.remove = __devexit_p(gpio_regulator_remove),
	.driver = {
	.name = "gpio-regulator",
	.owner = THIS_MODULE,
	},
	};

	static int __init gpio_regulator_init(void)
	{
	return platform_driver_register(&gpio_regulator_driver);
	}
	subsys_initcall(gpio_regulator_init);

	static void __exit gpio_regulator_exit(void)
	{
	platform_driver_unregister(&gpio_regulator_driver);
	}
	module_exit(gpio_regulator_exit);

	MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
	MODULE_DESCRIPTION("gpio voltage regulator");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:gpio-regulator");