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linux-2.6/drivers/regulator/gpio-regulator.c
Mark Brown c172708d38 regulator: core: Use a struct to pass in regulator runtime configuration
Rather than adding new arguments to regulator_register() every time we
want to add a new bit of dynamic information at runtime change the function
to take these via a struct. By doing this we avoid needing to do further
changes like the recent addition of device tree support which required each
regulator driver to be updated to take an additional parameter.

The regulator_desc which should (mostly) be static data is still passed
separately as most drivers are able to configure this statically at build
time.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 12:37:09 +01:00

362 lines
9 KiB
C

/*
* 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, best_val = INT_MAX;
for (ptr = 0; ptr < data->nr_states; ptr++)
if (data->states[ptr].value < best_val &&
data->states[ptr].value >= min &&
data->states[ptr].value <= max)
target = data->states[ptr].gpios;
if (best_val == INT_MAX)
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;
struct regulator_config cfg = { };
int ptr, ret, state;
drvdata = devm_kzalloc(&pdev->dev, 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;
cfg.dev = &pdev->dev;
cfg.init_data = config->init_data;
cfg.driver_data = &drvdata;
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_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:
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);
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");