blob: 85c59726f3c8ba554766a9362a49c95e9ea0d4a0 [file] [log] [blame]
/*
* Copyright (c) 2012, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/module.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regulator/stub-regulator.h>
#define STUB_REGULATOR_MAX_NAME 40
struct regulator_stub {
struct regulator_desc rdesc;
struct regulator_dev *rdev;
int voltage;
bool enabled;
int mode;
int hpm_min_load;
int system_uA;
char name[STUB_REGULATOR_MAX_NAME];
};
static int regulator_stub_set_voltage(struct regulator_dev *rdev, int min_uV,
int max_uV, unsigned *selector)
{
struct regulator_stub *vreg_priv = rdev_get_drvdata(rdev);
vreg_priv->voltage = min_uV;
return 0;
}
static int regulator_stub_get_voltage(struct regulator_dev *rdev)
{
struct regulator_stub *vreg_priv = rdev_get_drvdata(rdev);
return vreg_priv->voltage;
}
static int regulator_stub_list_voltage(struct regulator_dev *rdev,
unsigned selector)
{
struct regulation_constraints *constraints = rdev->constraints;
if (selector >= 2)
return -EINVAL;
else if (selector == 0)
return constraints->min_uV;
else
return constraints->max_uV;
}
static unsigned int regulator_stub_get_mode(struct regulator_dev *rdev)
{
struct regulator_stub *vreg_priv = rdev_get_drvdata(rdev);
return vreg_priv->mode;
}
static int regulator_stub_set_mode(struct regulator_dev *rdev,
unsigned int mode)
{
struct regulator_stub *vreg_priv = rdev_get_drvdata(rdev);
if (mode != REGULATOR_MODE_NORMAL && mode != REGULATOR_MODE_IDLE) {
dev_err(&rdev->dev, "%s: invalid mode requested %u\n",
__func__, mode);
return -EINVAL;
}
vreg_priv->mode = mode;
return 0;
}
static unsigned int regulator_stub_get_optimum_mode(struct regulator_dev *rdev,
int input_uV, int output_uV, int load_uA)
{
struct regulator_stub *vreg_priv = rdev_get_drvdata(rdev);
unsigned int mode;
if (load_uA + vreg_priv->system_uA >= vreg_priv->hpm_min_load)
mode = REGULATOR_MODE_NORMAL;
else
mode = REGULATOR_MODE_IDLE;
return mode;
}
static int regulator_stub_enable(struct regulator_dev *rdev)
{
struct regulator_stub *vreg_priv = rdev_get_drvdata(rdev);
vreg_priv->enabled = true;
return 0;
}
static int regulator_stub_disable(struct regulator_dev *rdev)
{
struct regulator_stub *vreg_priv = rdev_get_drvdata(rdev);
vreg_priv->enabled = false;
return 0;
}
static int regulator_stub_is_enabled(struct regulator_dev *rdev)
{
struct regulator_stub *vreg_priv = rdev_get_drvdata(rdev);
return vreg_priv->enabled;
}
/* Real regulator operations. */
static struct regulator_ops regulator_stub_ops = {
.enable = regulator_stub_enable,
.disable = regulator_stub_disable,
.is_enabled = regulator_stub_is_enabled,
.set_voltage = regulator_stub_set_voltage,
.get_voltage = regulator_stub_get_voltage,
.list_voltage = regulator_stub_list_voltage,
.set_mode = regulator_stub_set_mode,
.get_mode = regulator_stub_get_mode,
.get_optimum_mode = regulator_stub_get_optimum_mode,
};
static void regulator_stub_cleanup(struct regulator_stub *vreg_priv)
{
if (vreg_priv && vreg_priv->rdev)
regulator_unregister(vreg_priv->rdev);
kfree(vreg_priv);
}
static int __devinit regulator_stub_probe(struct platform_device *pdev)
{
struct regulator_init_data *init_data = NULL;
struct device *dev = &pdev->dev;
struct stub_regulator_pdata *vreg_pdata;
struct regulator_desc *rdesc;
struct regulator_stub *vreg_priv;
int rc;
vreg_priv = kzalloc(sizeof(*vreg_priv), GFP_KERNEL);
if (!vreg_priv) {
dev_err(dev, "%s: Unable to allocate memory\n",
__func__);
return -ENOMEM;
}
if (dev->of_node) {
/* Use device tree. */
init_data = of_get_regulator_init_data(dev,
dev->of_node);
if (!init_data) {
dev_err(dev, "%s: unable to allocate memory\n",
__func__);
rc = -ENOMEM;
goto err_probe;
}
if (init_data->constraints.name == NULL) {
dev_err(dev, "%s: regulator name not specified\n",
__func__);
rc = -EINVAL;
goto err_probe;
}
if (of_get_property(dev->of_node, "parent-supply", NULL))
init_data->supply_regulator = "parent";
of_property_read_u32(dev->of_node, "qcom,system-load",
&vreg_priv->system_uA);
of_property_read_u32(dev->of_node, "qcom,hpm-min-load",
&vreg_priv->hpm_min_load);
init_data->constraints.input_uV = init_data->constraints.max_uV;
init_data->constraints.valid_ops_mask
|= REGULATOR_CHANGE_STATUS;
init_data->constraints.valid_ops_mask
|= REGULATOR_CHANGE_VOLTAGE;
init_data->constraints.valid_ops_mask
|= REGULATOR_CHANGE_MODE | REGULATOR_CHANGE_DRMS;
init_data->constraints.valid_modes_mask
= REGULATOR_MODE_NORMAL | REGULATOR_MODE_IDLE;
} else {
/* Use platform data. */
vreg_pdata = dev->platform_data;
if (!vreg_pdata) {
dev_err(dev, "%s: no platform data\n", __func__);
rc = -EINVAL;
goto err_probe;
}
init_data = &vreg_pdata->init_data;
vreg_priv->system_uA = vreg_pdata->system_uA;
vreg_priv->hpm_min_load = vreg_pdata->hpm_min_load;
}
dev_set_drvdata(dev, vreg_priv);
rdesc = &vreg_priv->rdesc;
strlcpy(vreg_priv->name, init_data->constraints.name,
STUB_REGULATOR_MAX_NAME);
rdesc->name = vreg_priv->name;
rdesc->ops = &regulator_stub_ops;
/*
* Ensure that voltage set points are handled correctly for regulators
* which have a specified voltage constraint range, as well as those
* that do not.
*/
if (init_data->constraints.min_uV == 0 &&
init_data->constraints.max_uV == 0)
rdesc->n_voltages = 0;
else
rdesc->n_voltages = 2;
rdesc->id = pdev->id;
rdesc->owner = THIS_MODULE;
rdesc->type = REGULATOR_VOLTAGE;
vreg_priv->voltage = init_data->constraints.min_uV;
if (vreg_priv->system_uA >= vreg_priv->hpm_min_load)
vreg_priv->mode = REGULATOR_MODE_NORMAL;
else
vreg_priv->mode = REGULATOR_MODE_IDLE;
vreg_priv->rdev = regulator_register(rdesc, dev, init_data, vreg_priv,
dev->of_node);
if (IS_ERR(vreg_priv->rdev)) {
rc = PTR_ERR(vreg_priv->rdev);
vreg_priv->rdev = NULL;
if (rc != -EPROBE_DEFER)
dev_err(dev, "%s: regulator_register failed\n",
__func__);
goto err_probe;
}
return 0;
err_probe:
regulator_stub_cleanup(vreg_priv);
return rc;
}
static int __devexit regulator_stub_remove(struct platform_device *pdev)
{
struct regulator_stub *vreg_priv = dev_get_drvdata(&pdev->dev);
regulator_stub_cleanup(vreg_priv);
return 0;
}
static struct of_device_id regulator_stub_match_table[] = {
{ .compatible = "qcom," STUB_REGULATOR_DRIVER_NAME, },
{}
};
static struct platform_driver regulator_stub_driver = {
.probe = regulator_stub_probe,
.remove = __devexit_p(regulator_stub_remove),
.driver = {
.name = STUB_REGULATOR_DRIVER_NAME,
.owner = THIS_MODULE,
.of_match_table = regulator_stub_match_table,
},
};
int __init regulator_stub_init(void)
{
static int registered;
if (registered)
return 0;
else
registered = 1;
return platform_driver_register(&regulator_stub_driver);
}
postcore_initcall(regulator_stub_init);
EXPORT_SYMBOL(regulator_stub_init);
static void __exit regulator_stub_exit(void)
{
platform_driver_unregister(&regulator_stub_driver);
}
module_exit(regulator_stub_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("stub regulator driver");
MODULE_VERSION("1.0");
MODULE_ALIAS("platform: " STUB_REGULATOR_DRIVER_NAME);