acrn-kernel/drivers/regulator/fixed.c

131 lines
3.1 KiB
C

/*
* fixed.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.
*
* 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/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/fixed.h>
struct fixed_voltage_data {
struct regulator_desc desc;
struct regulator_dev *dev;
int microvolts;
};
static int fixed_voltage_is_enabled(struct regulator_dev *dev)
{
return 1;
}
static int fixed_voltage_enable(struct regulator_dev *dev)
{
return 0;
}
static int fixed_voltage_get_voltage(struct regulator_dev *dev)
{
struct fixed_voltage_data *data = rdev_get_drvdata(dev);
return data->microvolts;
}
static struct regulator_ops fixed_voltage_ops = {
.is_enabled = fixed_voltage_is_enabled,
.enable = fixed_voltage_enable,
.get_voltage = fixed_voltage_get_voltage,
};
static int regulator_fixed_voltage_probe(struct platform_device *pdev)
{
struct fixed_voltage_config *config = pdev->dev.platform_data;
struct fixed_voltage_data *drvdata;
int ret;
drvdata = kzalloc(sizeof(struct fixed_voltage_data), GFP_KERNEL);
if (drvdata == NULL) {
ret = -ENOMEM;
goto err;
}
drvdata->desc.name = kstrdup(config->supply_name, GFP_KERNEL);
if (drvdata->desc.name == NULL) {
ret = -ENOMEM;
goto err;
}
drvdata->desc.type = REGULATOR_VOLTAGE;
drvdata->desc.owner = THIS_MODULE;
drvdata->desc.ops = &fixed_voltage_ops,
drvdata->microvolts = config->microvolts;
drvdata->dev = regulator_register(&drvdata->desc, &pdev->dev,
config->init_data, drvdata);
if (IS_ERR(drvdata->dev)) {
ret = PTR_ERR(drvdata->dev);
goto err_name;
}
platform_set_drvdata(pdev, drvdata);
dev_dbg(&pdev->dev, "%s supplying %duV\n", drvdata->desc.name,
drvdata->microvolts);
return 0;
err_name:
kfree(drvdata->desc.name);
err:
kfree(drvdata);
return ret;
}
static int regulator_fixed_voltage_remove(struct platform_device *pdev)
{
struct fixed_voltage_data *drvdata = platform_get_drvdata(pdev);
regulator_unregister(drvdata->dev);
kfree(drvdata->desc.name);
kfree(drvdata);
return 0;
}
static struct platform_driver regulator_fixed_voltage_driver = {
.probe = regulator_fixed_voltage_probe,
.remove = regulator_fixed_voltage_remove,
.driver = {
.name = "reg-fixed-voltage",
},
};
static int __init regulator_fixed_voltage_init(void)
{
return platform_driver_register(&regulator_fixed_voltage_driver);
}
module_init(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");