blob: 629fee0dd45c68abd5ae96f9cc6f6f95ae948104 [file] [log] [blame]
/*
* Copyright (c) 2017, 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.
*/
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.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/machine.h>
#include <linux/regulator/of_regulator.h>
#define REFGEN_REG_BIAS_EN 0x08
#define REFGEN_BIAS_EN_MASK GENMASK(2, 0)
#define REFGEN_BIAS_EN_ENABLE 0x7
#define REFGEN_BIAS_EN_DISABLE 0x6
#define REFGEN_REG_BG_CTRL 0x14
#define REFGEN_BG_CTRL_MASK GENMASK(2, 0)
#define REFGEN_BG_CTRL_ENABLE 0x6
#define REFGEN_BG_CTRL_DISABLE 0x4
struct refgen {
struct regulator_desc rdesc;
struct regulator_dev *rdev;
void __iomem *addr;
};
static int refgen_enable(struct regulator_dev *rdev)
{
struct refgen *vreg = rdev_get_drvdata(rdev);
writel_relaxed(REFGEN_BG_CTRL_ENABLE, vreg->addr + REFGEN_REG_BG_CTRL);
writel_relaxed(REFGEN_BIAS_EN_ENABLE, vreg->addr + REFGEN_REG_BIAS_EN);
return 0;
}
static int refgen_disable(struct regulator_dev *rdev)
{
struct refgen *vreg = rdev_get_drvdata(rdev);
writel_relaxed(REFGEN_BIAS_EN_DISABLE, vreg->addr + REFGEN_REG_BIAS_EN);
writel_relaxed(REFGEN_BG_CTRL_DISABLE, vreg->addr + REFGEN_REG_BG_CTRL);
return 0;
}
static int refgen_is_enabled(struct regulator_dev *rdev)
{
struct refgen *vreg = rdev_get_drvdata(rdev);
u32 val;
val = readl_relaxed(vreg->addr + REFGEN_REG_BG_CTRL);
if ((val & REFGEN_BG_CTRL_MASK) != REFGEN_BG_CTRL_ENABLE)
return 0;
val = readl_relaxed(vreg->addr + REFGEN_REG_BIAS_EN);
if ((val & REFGEN_BIAS_EN_MASK) != REFGEN_BIAS_EN_ENABLE)
return 0;
return 1;
}
static struct regulator_ops refgen_ops = {
.enable = refgen_enable,
.disable = refgen_disable,
.is_enabled = refgen_is_enabled,
};
static int refgen_probe(struct platform_device *pdev)
{
struct regulator_config config = {};
struct regulator_init_data *init_data = NULL;
struct device *dev = &pdev->dev;
struct regulator_desc *rdesc;
struct resource *res;
struct refgen *vreg;
int rc;
vreg = devm_kzalloc(dev, sizeof(*vreg), GFP_KERNEL);
if (!vreg)
return -ENOMEM;
if (!dev->of_node) {
dev_err(dev, "%s: device tree node missing\n", __func__);
return -ENODEV;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res || !res->start) {
dev_err(dev, "reg address is missing\n");
return -EINVAL;
}
vreg->addr = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(vreg->addr)) {
rc = PTR_ERR(vreg->addr);
dev_err(dev, "ioremap failed, rc=%d\n", rc);
return rc;
}
init_data = of_get_regulator_init_data(dev, dev->of_node, &vreg->rdesc);
if (!init_data)
return -ENOMEM;
if (init_data->constraints.name == NULL) {
dev_err(dev, "%s: regulator-name not specified\n", __func__);
return -EINVAL;
}
if (of_get_property(dev->of_node, "parent-supply", NULL))
init_data->supply_regulator = "parent";
rdesc = &vreg->rdesc;
rdesc->name = "refgen";
rdesc->ops = &refgen_ops;
rdesc->id = pdev->id;
rdesc->owner = THIS_MODULE;
rdesc->type = REGULATOR_VOLTAGE;
config.dev = dev;
config.init_data = init_data;
config.driver_data = vreg;
config.of_node = dev->of_node;
vreg->rdev = devm_regulator_register(dev, rdesc, &config);
if (IS_ERR(vreg->rdev)) {
rc = PTR_ERR(vreg->rdev);
if (rc != -EPROBE_DEFER)
dev_err(dev, "%s: regulator register failed\n",
__func__);
return rc;
}
return 0;
}
static const struct of_device_id refgen_match_table[] = {
{ .compatible = "qcom,refgen-regulator", },
{}
};
static struct platform_driver refgen_driver = {
.probe = refgen_probe,
.driver = {
.name = "qcom,refgen-regulator",
.owner = THIS_MODULE,
.of_match_table = refgen_match_table,
},
};
static int __init refgen_init(void)
{
return platform_driver_register(&refgen_driver);
}
arch_initcall(refgen_init);
static void __exit refgen_exit(void)
{
platform_driver_unregister(&refgen_driver);
}
module_exit(refgen_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("refgen regulator driver");