mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
![Jisheng Zhang](/assets/img/avatar_default.png)
Fix below warning when CONFIG_OF=n: drivers/regulator/stm32-vrefbuf.c:287:34: warning: ‘stm32_vrefbuf_of_match’ defined but not used [-Wunused-const-variable=] 287 | static const struct of_device_id stm32_vrefbuf_of_match[] = { | ^~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com> Link: https://lore.kernel.org/r/20200821111755.4c461039@xhacker.debian Signed-off-by: Mark Brown <broonie@kernel.org>
307 lines
7.6 KiB
C
307 lines
7.6 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright (C) STMicroelectronics 2017
|
|
*
|
|
* Author: Fabrice Gasnier <fabrice.gasnier@st.com>
|
|
*/
|
|
|
|
#include <linux/bitfield.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/io.h>
|
|
#include <linux/iopoll.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/regulator/driver.h>
|
|
#include <linux/regulator/of_regulator.h>
|
|
#include <linux/pm_runtime.h>
|
|
|
|
/* STM32 VREFBUF registers */
|
|
#define STM32_VREFBUF_CSR 0x00
|
|
|
|
/* STM32 VREFBUF CSR bitfields */
|
|
#define STM32_VRS GENMASK(6, 4)
|
|
#define STM32_VRR BIT(3)
|
|
#define STM32_HIZ BIT(1)
|
|
#define STM32_ENVR BIT(0)
|
|
|
|
#define STM32_VREFBUF_AUTO_SUSPEND_DELAY_MS 10
|
|
|
|
struct stm32_vrefbuf {
|
|
void __iomem *base;
|
|
struct clk *clk;
|
|
struct device *dev;
|
|
};
|
|
|
|
static const unsigned int stm32_vrefbuf_voltages[] = {
|
|
/* Matches resp. VRS = 000b, 001b, 010b, 011b */
|
|
2500000, 2048000, 1800000, 1500000,
|
|
};
|
|
|
|
static int stm32_vrefbuf_enable(struct regulator_dev *rdev)
|
|
{
|
|
struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);
|
|
u32 val;
|
|
int ret;
|
|
|
|
ret = pm_runtime_get_sync(priv->dev);
|
|
if (ret < 0) {
|
|
pm_runtime_put_noidle(priv->dev);
|
|
return ret;
|
|
}
|
|
|
|
val = readl_relaxed(priv->base + STM32_VREFBUF_CSR);
|
|
val = (val & ~STM32_HIZ) | STM32_ENVR;
|
|
writel_relaxed(val, priv->base + STM32_VREFBUF_CSR);
|
|
|
|
/*
|
|
* Vrefbuf startup time depends on external capacitor: wait here for
|
|
* VRR to be set. That means output has reached expected value.
|
|
* ~650us sleep should be enough for caps up to 1.5uF. Use 10ms as
|
|
* arbitrary timeout.
|
|
*/
|
|
ret = readl_poll_timeout(priv->base + STM32_VREFBUF_CSR, val,
|
|
val & STM32_VRR, 650, 10000);
|
|
if (ret) {
|
|
dev_err(&rdev->dev, "stm32 vrefbuf timed out!\n");
|
|
val = readl_relaxed(priv->base + STM32_VREFBUF_CSR);
|
|
val = (val & ~STM32_ENVR) | STM32_HIZ;
|
|
writel_relaxed(val, priv->base + STM32_VREFBUF_CSR);
|
|
}
|
|
|
|
pm_runtime_mark_last_busy(priv->dev);
|
|
pm_runtime_put_autosuspend(priv->dev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int stm32_vrefbuf_disable(struct regulator_dev *rdev)
|
|
{
|
|
struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);
|
|
u32 val;
|
|
int ret;
|
|
|
|
ret = pm_runtime_get_sync(priv->dev);
|
|
if (ret < 0) {
|
|
pm_runtime_put_noidle(priv->dev);
|
|
return ret;
|
|
}
|
|
|
|
val = readl_relaxed(priv->base + STM32_VREFBUF_CSR);
|
|
val &= ~STM32_ENVR;
|
|
writel_relaxed(val, priv->base + STM32_VREFBUF_CSR);
|
|
|
|
pm_runtime_mark_last_busy(priv->dev);
|
|
pm_runtime_put_autosuspend(priv->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int stm32_vrefbuf_is_enabled(struct regulator_dev *rdev)
|
|
{
|
|
struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);
|
|
int ret;
|
|
|
|
ret = pm_runtime_get_sync(priv->dev);
|
|
if (ret < 0) {
|
|
pm_runtime_put_noidle(priv->dev);
|
|
return ret;
|
|
}
|
|
|
|
ret = readl_relaxed(priv->base + STM32_VREFBUF_CSR) & STM32_ENVR;
|
|
|
|
pm_runtime_mark_last_busy(priv->dev);
|
|
pm_runtime_put_autosuspend(priv->dev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int stm32_vrefbuf_set_voltage_sel(struct regulator_dev *rdev,
|
|
unsigned sel)
|
|
{
|
|
struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);
|
|
u32 val;
|
|
int ret;
|
|
|
|
ret = pm_runtime_get_sync(priv->dev);
|
|
if (ret < 0) {
|
|
pm_runtime_put_noidle(priv->dev);
|
|
return ret;
|
|
}
|
|
|
|
val = readl_relaxed(priv->base + STM32_VREFBUF_CSR);
|
|
val = (val & ~STM32_VRS) | FIELD_PREP(STM32_VRS, sel);
|
|
writel_relaxed(val, priv->base + STM32_VREFBUF_CSR);
|
|
|
|
pm_runtime_mark_last_busy(priv->dev);
|
|
pm_runtime_put_autosuspend(priv->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int stm32_vrefbuf_get_voltage_sel(struct regulator_dev *rdev)
|
|
{
|
|
struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);
|
|
u32 val;
|
|
int ret;
|
|
|
|
ret = pm_runtime_get_sync(priv->dev);
|
|
if (ret < 0) {
|
|
pm_runtime_put_noidle(priv->dev);
|
|
return ret;
|
|
}
|
|
|
|
val = readl_relaxed(priv->base + STM32_VREFBUF_CSR);
|
|
ret = FIELD_GET(STM32_VRS, val);
|
|
|
|
pm_runtime_mark_last_busy(priv->dev);
|
|
pm_runtime_put_autosuspend(priv->dev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct regulator_ops stm32_vrefbuf_volt_ops = {
|
|
.enable = stm32_vrefbuf_enable,
|
|
.disable = stm32_vrefbuf_disable,
|
|
.is_enabled = stm32_vrefbuf_is_enabled,
|
|
.get_voltage_sel = stm32_vrefbuf_get_voltage_sel,
|
|
.set_voltage_sel = stm32_vrefbuf_set_voltage_sel,
|
|
.list_voltage = regulator_list_voltage_table,
|
|
};
|
|
|
|
static const struct regulator_desc stm32_vrefbuf_regu = {
|
|
.name = "vref",
|
|
.supply_name = "vdda",
|
|
.volt_table = stm32_vrefbuf_voltages,
|
|
.n_voltages = ARRAY_SIZE(stm32_vrefbuf_voltages),
|
|
.ops = &stm32_vrefbuf_volt_ops,
|
|
.off_on_delay = 1000,
|
|
.type = REGULATOR_VOLTAGE,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static int stm32_vrefbuf_probe(struct platform_device *pdev)
|
|
{
|
|
struct stm32_vrefbuf *priv;
|
|
struct regulator_config config = { };
|
|
struct regulator_dev *rdev;
|
|
int ret;
|
|
|
|
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
|
|
if (!priv)
|
|
return -ENOMEM;
|
|
priv->dev = &pdev->dev;
|
|
|
|
priv->base = devm_platform_ioremap_resource(pdev, 0);
|
|
if (IS_ERR(priv->base))
|
|
return PTR_ERR(priv->base);
|
|
|
|
priv->clk = devm_clk_get(&pdev->dev, NULL);
|
|
if (IS_ERR(priv->clk))
|
|
return PTR_ERR(priv->clk);
|
|
|
|
pm_runtime_get_noresume(&pdev->dev);
|
|
pm_runtime_set_active(&pdev->dev);
|
|
pm_runtime_set_autosuspend_delay(&pdev->dev,
|
|
STM32_VREFBUF_AUTO_SUSPEND_DELAY_MS);
|
|
pm_runtime_use_autosuspend(&pdev->dev);
|
|
pm_runtime_enable(&pdev->dev);
|
|
|
|
ret = clk_prepare_enable(priv->clk);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "clk prepare failed with error %d\n", ret);
|
|
goto err_pm_stop;
|
|
}
|
|
|
|
config.dev = &pdev->dev;
|
|
config.driver_data = priv;
|
|
config.of_node = pdev->dev.of_node;
|
|
config.init_data = of_get_regulator_init_data(&pdev->dev,
|
|
pdev->dev.of_node,
|
|
&stm32_vrefbuf_regu);
|
|
|
|
rdev = regulator_register(&stm32_vrefbuf_regu, &config);
|
|
if (IS_ERR(rdev)) {
|
|
ret = PTR_ERR(rdev);
|
|
dev_err(&pdev->dev, "register failed with error %d\n", ret);
|
|
goto err_clk_dis;
|
|
}
|
|
platform_set_drvdata(pdev, rdev);
|
|
|
|
pm_runtime_mark_last_busy(&pdev->dev);
|
|
pm_runtime_put_autosuspend(&pdev->dev);
|
|
|
|
return 0;
|
|
|
|
err_clk_dis:
|
|
clk_disable_unprepare(priv->clk);
|
|
err_pm_stop:
|
|
pm_runtime_disable(&pdev->dev);
|
|
pm_runtime_set_suspended(&pdev->dev);
|
|
pm_runtime_put_noidle(&pdev->dev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int stm32_vrefbuf_remove(struct platform_device *pdev)
|
|
{
|
|
struct regulator_dev *rdev = platform_get_drvdata(pdev);
|
|
struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);
|
|
|
|
pm_runtime_get_sync(&pdev->dev);
|
|
regulator_unregister(rdev);
|
|
clk_disable_unprepare(priv->clk);
|
|
pm_runtime_disable(&pdev->dev);
|
|
pm_runtime_set_suspended(&pdev->dev);
|
|
pm_runtime_put_noidle(&pdev->dev);
|
|
|
|
return 0;
|
|
};
|
|
|
|
static int __maybe_unused stm32_vrefbuf_runtime_suspend(struct device *dev)
|
|
{
|
|
struct regulator_dev *rdev = dev_get_drvdata(dev);
|
|
struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);
|
|
|
|
clk_disable_unprepare(priv->clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __maybe_unused stm32_vrefbuf_runtime_resume(struct device *dev)
|
|
{
|
|
struct regulator_dev *rdev = dev_get_drvdata(dev);
|
|
struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);
|
|
|
|
return clk_prepare_enable(priv->clk);
|
|
}
|
|
|
|
static const struct dev_pm_ops stm32_vrefbuf_pm_ops = {
|
|
SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
|
|
pm_runtime_force_resume)
|
|
SET_RUNTIME_PM_OPS(stm32_vrefbuf_runtime_suspend,
|
|
stm32_vrefbuf_runtime_resume,
|
|
NULL)
|
|
};
|
|
|
|
static const struct of_device_id __maybe_unused stm32_vrefbuf_of_match[] = {
|
|
{ .compatible = "st,stm32-vrefbuf", },
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, stm32_vrefbuf_of_match);
|
|
|
|
static struct platform_driver stm32_vrefbuf_driver = {
|
|
.probe = stm32_vrefbuf_probe,
|
|
.remove = stm32_vrefbuf_remove,
|
|
.driver = {
|
|
.name = "stm32-vrefbuf",
|
|
.of_match_table = of_match_ptr(stm32_vrefbuf_of_match),
|
|
.pm = &stm32_vrefbuf_pm_ops,
|
|
},
|
|
};
|
|
module_platform_driver(stm32_vrefbuf_driver);
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
|
|
MODULE_DESCRIPTION("STMicroelectronics STM32 VREFBUF driver");
|
|
MODULE_ALIAS("platform:stm32-vrefbuf");
|