linux/drivers/regulator/gpio-regulator.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

369 lines
9.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 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 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/of_regulator.h>
#include <linux/regulator/gpio-regulator.h>
#include <linux/gpio/consumer.h>
#include <linux/slab.h>
#include <linux/of.h>
struct gpio_regulator_data {
struct regulator_desc desc;
struct gpio_desc **gpiods;
int nr_gpios;
struct gpio_regulator_state *states;
int nr_states;
int state;
};
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_voltage(struct regulator_dev *dev,
int min_uV, int max_uV,
unsigned *selector)
{
struct gpio_regulator_data *data = rdev_get_drvdata(dev);
int ptr, target = 0, 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_uV &&
data->states[ptr].value <= max_uV) {
target = data->states[ptr].gpios;
best_val = data->states[ptr].value;
if (selector)
*selector = ptr;
}
if (best_val == INT_MAX)
return -EINVAL;
for (ptr = 0; ptr < data->nr_gpios; ptr++) {
state = (target & (1 << ptr)) >> ptr;
gpiod_set_value_cansleep(data->gpiods[ptr], state);
}
data->state = target;
return 0;
}
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)
{
struct gpio_regulator_data *data = rdev_get_drvdata(dev);
int ptr, target = 0, state, best_val = 0;
for (ptr = 0; ptr < data->nr_states; ptr++)
if (data->states[ptr].value > best_val &&
data->states[ptr].value >= min_uA &&
data->states[ptr].value <= max_uA) {
target = data->states[ptr].gpios;
best_val = data->states[ptr].value;
}
if (best_val == 0)
return -EINVAL;
for (ptr = 0; ptr < data->nr_gpios; ptr++) {
state = (target & (1 << ptr)) >> ptr;
gpiod_set_value_cansleep(data->gpiods[ptr], state);
}
data->state = target;
return 0;
}
static const struct regulator_ops gpio_regulator_voltage_ops = {
.get_voltage = gpio_regulator_get_value,
.set_voltage = gpio_regulator_set_voltage,
.list_voltage = gpio_regulator_list_voltage,
};
static struct gpio_regulator_config *
of_get_gpio_regulator_config(struct device *dev, struct device_node *np,
const struct regulator_desc *desc)
{
struct gpio_regulator_config *config;
const char *regtype;
int proplen, i;
int ngpios;
int ret;
config = devm_kzalloc(dev,
sizeof(struct gpio_regulator_config),
GFP_KERNEL);
if (!config)
return ERR_PTR(-ENOMEM);
config->init_data = of_get_regulator_init_data(dev, np, desc);
if (!config->init_data)
return ERR_PTR(-EINVAL);
config->supply_name = config->init_data->constraints.name;
if (of_property_read_bool(np, "enable-at-boot"))
config->enabled_at_boot = true;
of_property_read_u32(np, "startup-delay-us", &config->startup_delay);
/* Fetch GPIO init levels */
ngpios = gpiod_count(dev, NULL);
if (ngpios > 0) {
config->gflags = devm_kzalloc(dev,
sizeof(enum gpiod_flags)
* ngpios,
GFP_KERNEL);
if (!config->gflags)
return ERR_PTR(-ENOMEM);
for (i = 0; i < ngpios; i++) {
u32 val;
ret = of_property_read_u32_index(np, "gpios-states", i,
&val);
/* Default to high per specification */
if (ret)
config->gflags[i] = GPIOD_OUT_HIGH;
else
config->gflags[i] =
val ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
}
}
config->ngpios = ngpios;
/* Fetch states. */
proplen = of_property_count_u32_elems(np, "states");
if (proplen < 0) {
dev_err(dev, "No 'states' property found\n");
return ERR_PTR(-EINVAL);
}
config->states = devm_kcalloc(dev,
proplen / 2,
sizeof(struct gpio_regulator_state),
GFP_KERNEL);
if (!config->states)
return ERR_PTR(-ENOMEM);
for (i = 0; i < proplen / 2; i++) {
of_property_read_u32_index(np, "states", i * 2,
&config->states[i].value);
of_property_read_u32_index(np, "states", i * 2 + 1,
&config->states[i].gpios);
}
config->nr_states = i;
config->type = REGULATOR_VOLTAGE;
ret = of_property_read_string(np, "regulator-type", &regtype);
if (ret >= 0) {
if (!strncmp("voltage", regtype, 7))
config->type = REGULATOR_VOLTAGE;
else if (!strncmp("current", regtype, 7))
config->type = REGULATOR_CURRENT;
else
dev_warn(dev, "Unknown regulator-type '%s'\n",
regtype);
}
return config;
}
static const struct regulator_ops gpio_regulator_current_ops = {
.get_current_limit = gpio_regulator_get_value,
.set_current_limit = gpio_regulator_set_current_limit,
};
static int gpio_regulator_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct gpio_regulator_config *config = dev_get_platdata(dev);
struct device_node *np = dev->of_node;
struct gpio_regulator_data *drvdata;
struct regulator_config cfg = { };
struct regulator_dev *rdev;
enum gpiod_flags gflags;
int ptr, ret, state, i;
drvdata = devm_kzalloc(dev, sizeof(struct gpio_regulator_data),
GFP_KERNEL);
if (drvdata == NULL)
return -ENOMEM;
if (np) {
config = of_get_gpio_regulator_config(dev, np,
&drvdata->desc);
if (IS_ERR(config))
return PTR_ERR(config);
}
drvdata->desc.name = devm_kstrdup(dev, config->supply_name, GFP_KERNEL);
if (drvdata->desc.name == NULL) {
dev_err(dev, "Failed to allocate supply name\n");
return -ENOMEM;
}
drvdata->gpiods = devm_kzalloc(dev, sizeof(struct gpio_desc *),
GFP_KERNEL);
if (!drvdata->gpiods)
return -ENOMEM;
for (i = 0; i < config->ngpios; i++) {
drvdata->gpiods[i] = devm_gpiod_get_index(dev,
NULL,
i,
config->gflags[i]);
if (IS_ERR(drvdata->gpiods[i]))
return PTR_ERR(drvdata->gpiods[i]);
/* This is good to know */
gpiod_set_consumer_name(drvdata->gpiods[i], drvdata->desc.name);
}
drvdata->nr_gpios = config->ngpios;
drvdata->states = devm_kmemdup(dev,
config->states,
config->nr_states *
sizeof(struct gpio_regulator_state),
GFP_KERNEL);
if (drvdata->states == NULL) {
dev_err(dev, "Failed to allocate state data\n");
return -ENOMEM;
}
drvdata->nr_states = config->nr_states;
drvdata->desc.owner = THIS_MODULE;
drvdata->desc.enable_time = config->startup_delay;
/* 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(dev, "No regulator type set\n");
return -EINVAL;
}
/* build initial state from gpio init data. */
state = 0;
for (ptr = 0; ptr < drvdata->nr_gpios; ptr++) {
if (config->gflags[ptr] == GPIOD_OUT_HIGH)
state |= (1 << ptr);
}
drvdata->state = state;
cfg.dev = dev;
cfg.init_data = config->init_data;
cfg.driver_data = drvdata;
cfg.of_node = np;
/*
* The signal will be inverted by the GPIO core if flagged so in the
* decriptor.
*/
if (config->enabled_at_boot)
gflags = GPIOD_OUT_HIGH | GPIOD_FLAGS_BIT_NONEXCLUSIVE;
else
gflags = GPIOD_OUT_LOW | GPIOD_FLAGS_BIT_NONEXCLUSIVE;
cfg.ena_gpiod = gpiod_get_optional(dev, "enable", gflags);
if (IS_ERR(cfg.ena_gpiod))
return PTR_ERR(cfg.ena_gpiod);
rdev = devm_regulator_register(dev, &drvdata->desc, &cfg);
if (IS_ERR(rdev)) {
ret = PTR_ERR(rdev);
dev_err(dev, "Failed to register regulator: %d\n", ret);
return ret;
}
platform_set_drvdata(pdev, drvdata);
return 0;
}
#if defined(CONFIG_OF)
static const struct of_device_id regulator_gpio_of_match[] = {
{ .compatible = "regulator-gpio", },
{},
};
MODULE_DEVICE_TABLE(of, regulator_gpio_of_match);
#endif
static struct platform_driver gpio_regulator_driver = {
.probe = gpio_regulator_probe,
.driver = {
.name = "gpio-regulator",
.of_match_table = of_match_ptr(regulator_gpio_of_match),
},
};
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");