mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 09:19:51 +00:00
![Jisheng Zhang](/assets/img/avatar_default.png)
The function of_get_named_gpio() could return -ENOENT, -EPROBE_DEFER -EINVAL and so on. Currently, for the optional property "enable-gpio", we only check -EPROBE_DEFER, this is not enough since there may be misconfigured "enable-gpio" in the DTB, of_get_named_gpio() will return -EINVAL in this case, we should return immediately here. And for the optional property "gpios", we didn't check the return value, the driver will continue to the point where gpio_request_array() is called, it doesn't make sense to continue if we got -EPROBE_DEFER or -EINVAL here. This patch tries to address these two issues by properly checking the return value of of_get_named_gpio. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Signed-off-by: Mark Brown <broonie@kernel.org>
431 lines
11 KiB
C
431 lines
11 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/of_regulator.h>
|
|
#include <linux/regulator/gpio-regulator.h>
|
|
#include <linux/gpio.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_gpio.h>
|
|
|
|
struct gpio_regulator_data {
|
|
struct regulator_desc desc;
|
|
struct regulator_dev *dev;
|
|
|
|
struct gpio *gpios;
|
|
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;
|
|
gpio_set_value_cansleep(data->gpios[ptr].gpio, 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;
|
|
gpio_set_value_cansleep(data->gpios[ptr].gpio, state);
|
|
}
|
|
data->state = target;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static 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, gpio, i;
|
|
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-active-high"))
|
|
config->enable_high = true;
|
|
|
|
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);
|
|
|
|
config->enable_gpio = of_get_named_gpio(np, "enable-gpio", 0);
|
|
if (config->enable_gpio < 0 && config->enable_gpio != -ENOENT)
|
|
return ERR_PTR(config->enable_gpio);
|
|
|
|
/* Fetch GPIOs. - optional property*/
|
|
ret = of_gpio_count(np);
|
|
if ((ret < 0) && (ret != -ENOENT))
|
|
return ERR_PTR(ret);
|
|
|
|
if (ret > 0) {
|
|
config->nr_gpios = ret;
|
|
config->gpios = devm_kzalloc(dev,
|
|
sizeof(struct gpio) * config->nr_gpios,
|
|
GFP_KERNEL);
|
|
if (!config->gpios)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
proplen = of_property_count_u32_elems(np, "gpios-states");
|
|
/* optional property */
|
|
if (proplen < 0)
|
|
proplen = 0;
|
|
|
|
if (proplen > 0 && proplen != config->nr_gpios) {
|
|
dev_warn(dev, "gpios <-> gpios-states mismatch\n");
|
|
proplen = 0;
|
|
}
|
|
|
|
for (i = 0; i < config->nr_gpios; i++) {
|
|
gpio = of_get_named_gpio(np, "gpios", i);
|
|
if (gpio < 0) {
|
|
if (gpio != -ENOENT)
|
|
return ERR_PTR(gpio);
|
|
break;
|
|
}
|
|
config->gpios[i].gpio = gpio;
|
|
if (proplen > 0) {
|
|
of_property_read_u32_index(np, "gpios-states",
|
|
i, &ret);
|
|
if (ret)
|
|
config->gpios[i].flags =
|
|
GPIOF_OUT_INIT_HIGH;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* 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_kzalloc(dev,
|
|
sizeof(struct gpio_regulator_state)
|
|
* (proplen / 2),
|
|
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", ®type);
|
|
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 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 gpio_regulator_config *config = dev_get_platdata(&pdev->dev);
|
|
struct device_node *np = pdev->dev.of_node;
|
|
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)
|
|
return -ENOMEM;
|
|
|
|
if (np) {
|
|
config = of_get_gpio_regulator_config(&pdev->dev, np,
|
|
&drvdata->desc);
|
|
if (IS_ERR(config))
|
|
return PTR_ERR(config);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
if (config->nr_gpios != 0) {
|
|
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->nr_gpios = config->nr_gpios;
|
|
ret = gpio_request_array(drvdata->gpios, drvdata->nr_gpios);
|
|
if (ret) {
|
|
if (ret != -EPROBE_DEFER)
|
|
dev_err(&pdev->dev,
|
|
"Could not obtain regulator setting GPIOs: %d\n",
|
|
ret);
|
|
goto err_memstate;
|
|
}
|
|
}
|
|
|
|
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;
|
|
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(&pdev->dev, "No regulator type set\n");
|
|
ret = -EINVAL;
|
|
goto err_memgpio;
|
|
}
|
|
|
|
/* 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;
|
|
cfg.of_node = np;
|
|
|
|
if (gpio_is_valid(config->enable_gpio)) {
|
|
cfg.ena_gpio = config->enable_gpio;
|
|
cfg.ena_gpio_initialized = true;
|
|
}
|
|
cfg.ena_gpio_invert = !config->enable_high;
|
|
if (config->enabled_at_boot) {
|
|
if (config->enable_high)
|
|
cfg.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
|
|
else
|
|
cfg.ena_gpio_flags |= GPIOF_OUT_INIT_LOW;
|
|
} else {
|
|
if (config->enable_high)
|
|
cfg.ena_gpio_flags |= GPIOF_OUT_INIT_LOW;
|
|
else
|
|
cfg.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
|
|
}
|
|
|
|
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_memstate:
|
|
kfree(drvdata->states);
|
|
err_memgpio:
|
|
kfree(drvdata->gpios);
|
|
err_name:
|
|
kfree(drvdata->desc.name);
|
|
err:
|
|
return ret;
|
|
}
|
|
|
|
static int 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);
|
|
|
|
kfree(drvdata->desc.name);
|
|
|
|
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,
|
|
.remove = gpio_regulator_remove,
|
|
.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");
|