linux/drivers/regulator/stm32-pwr.c

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// SPDX-License-Identifier: GPL-2.0
// Copyright (C) STMicroelectronics 2019
// Authors: Gabriel Fernandez <gabriel.fernandez@st.com>
// Pascal Paillet <p.paillet@st.com>.
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>
/*
* Registers description
*/
#define REG_PWR_CR3 0x0C
#define USB_3_3_EN BIT(24)
#define USB_3_3_RDY BIT(26)
#define REG_1_8_EN BIT(28)
#define REG_1_8_RDY BIT(29)
#define REG_1_1_EN BIT(30)
#define REG_1_1_RDY BIT(31)
/* list of supported regulators */
enum {
PWR_REG11,
PWR_REG18,
PWR_USB33,
STM32PWR_REG_NUM_REGS
};
static u32 ready_mask_table[STM32PWR_REG_NUM_REGS] = {
[PWR_REG11] = REG_1_1_RDY,
[PWR_REG18] = REG_1_8_RDY,
[PWR_USB33] = USB_3_3_RDY,
};
struct stm32_pwr_reg {
void __iomem *base;
u32 ready_mask;
};
static int stm32_pwr_reg_is_ready(struct regulator_dev *rdev)
{
struct stm32_pwr_reg *priv = rdev_get_drvdata(rdev);
u32 val;
val = readl_relaxed(priv->base + REG_PWR_CR3);
return (val & priv->ready_mask);
}
static int stm32_pwr_reg_is_enabled(struct regulator_dev *rdev)
{
struct stm32_pwr_reg *priv = rdev_get_drvdata(rdev);
u32 val;
val = readl_relaxed(priv->base + REG_PWR_CR3);
return (val & rdev->desc->enable_mask);
}
static int stm32_pwr_reg_enable(struct regulator_dev *rdev)
{
struct stm32_pwr_reg *priv = rdev_get_drvdata(rdev);
int ret;
u32 val;
val = readl_relaxed(priv->base + REG_PWR_CR3);
val |= rdev->desc->enable_mask;
writel_relaxed(val, priv->base + REG_PWR_CR3);
/* use an arbitrary timeout of 20ms */
ret = readx_poll_timeout(stm32_pwr_reg_is_ready, rdev, val, val,
100, 20 * 1000);
if (ret)
dev_err(&rdev->dev, "regulator enable timed out!\n");
return ret;
}
static int stm32_pwr_reg_disable(struct regulator_dev *rdev)
{
struct stm32_pwr_reg *priv = rdev_get_drvdata(rdev);
int ret;
u32 val;
val = readl_relaxed(priv->base + REG_PWR_CR3);
val &= ~rdev->desc->enable_mask;
writel_relaxed(val, priv->base + REG_PWR_CR3);
/* use an arbitrary timeout of 20ms */
ret = readx_poll_timeout(stm32_pwr_reg_is_ready, rdev, val, !val,
100, 20 * 1000);
if (ret)
dev_err(&rdev->dev, "regulator disable timed out!\n");
return ret;
}
static const struct regulator_ops stm32_pwr_reg_ops = {
.enable = stm32_pwr_reg_enable,
.disable = stm32_pwr_reg_disable,
.is_enabled = stm32_pwr_reg_is_enabled,
};
#define PWR_REG(_id, _name, _volt, _en, _supply) \
[_id] = { \
.id = _id, \
.name = _name, \
.of_match = of_match_ptr(_name), \
.n_voltages = 1, \
.type = REGULATOR_VOLTAGE, \
.fixed_uV = _volt, \
.ops = &stm32_pwr_reg_ops, \
.enable_mask = _en, \
.owner = THIS_MODULE, \
.supply_name = _supply, \
} \
static const struct regulator_desc stm32_pwr_desc[] = {
PWR_REG(PWR_REG11, "reg11", 1100000, REG_1_1_EN, "vdd"),
PWR_REG(PWR_REG18, "reg18", 1800000, REG_1_8_EN, "vdd"),
PWR_REG(PWR_USB33, "usb33", 3300000, USB_3_3_EN, "vdd_3v3_usbfs"),
};
static int stm32_pwr_regulator_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct stm32_pwr_reg *priv;
void __iomem *base;
struct regulator_dev *rdev;
struct regulator_config config = { };
int i, ret = 0;
base = of_iomap(np, 0);
if (!base) {
dev_err(&pdev->dev, "Unable to map IO memory\n");
return -ENOMEM;
}
config.dev = &pdev->dev;
for (i = 0; i < STM32PWR_REG_NUM_REGS; i++) {
priv = devm_kzalloc(&pdev->dev, sizeof(struct stm32_pwr_reg),
GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->base = base;
priv->ready_mask = ready_mask_table[i];
config.driver_data = priv;
rdev = devm_regulator_register(&pdev->dev,
&stm32_pwr_desc[i],
&config);
if (IS_ERR(rdev)) {
ret = PTR_ERR(rdev);
dev_err(&pdev->dev,
"Failed to register regulator: %d\n", ret);
break;
}
}
return ret;
}
static const struct of_device_id __maybe_unused stm32_pwr_of_match[] = {
{ .compatible = "st,stm32mp1,pwr-reg", },
{},
};
MODULE_DEVICE_TABLE(of, stm32_pwr_of_match);
static struct platform_driver stm32_pwr_driver = {
.probe = stm32_pwr_regulator_probe,
.driver = {
.name = "stm32-pwr-regulator",
.of_match_table = of_match_ptr(stm32_pwr_of_match),
},
};
module_platform_driver(stm32_pwr_driver);
MODULE_DESCRIPTION("STM32MP1 PWR voltage regulator driver");
MODULE_AUTHOR("Pascal Paillet <p.paillet@st.com>");
MODULE_LICENSE("GPL v2");