mirror_ubuntu-kernels/drivers/hwmon/sy7636a-hwmon.c

107 lines
2.4 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Functions to access SY3686A power management chip temperature
*
* Copyright (C) 2021 reMarkable AS - http://www.remarkable.com/
*
* Authors: Lars Ivar Miljeteig <lars.ivar.miljeteig@remarkable.com>
* Alistair Francis <alistair@alistair23.me>
*/
#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/regulator/machine.h>
#include <linux/mfd/sy7636a.h>
static int sy7636a_read(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long *temp)
{
struct regmap *regmap = dev_get_drvdata(dev);
int ret, reg_val;
ret = regmap_read(regmap,
SY7636A_REG_TERMISTOR_READOUT, &reg_val);
if (ret)
return ret;
*temp = reg_val * 1000;
return 0;
}
static umode_t sy7636a_is_visible(const void *data,
enum hwmon_sensor_types type,
u32 attr, int channel)
{
if (type != hwmon_temp)
return 0;
if (attr != hwmon_temp_input)
return 0;
return 0444;
}
static const struct hwmon_ops sy7636a_hwmon_ops = {
.is_visible = sy7636a_is_visible,
.read = sy7636a_read,
};
static const struct hwmon_channel_info * const sy7636a_info[] = {
HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT),
NULL
};
static const struct hwmon_chip_info sy7636a_chip_info = {
.ops = &sy7636a_hwmon_ops,
.info = sy7636a_info,
};
static int sy7636a_sensor_probe(struct platform_device *pdev)
{
struct regmap *regmap = dev_get_regmap(pdev->dev.parent, NULL);
struct regulator *regulator;
struct device *hwmon_dev;
int err;
if (!regmap)
return -EPROBE_DEFER;
regulator = devm_regulator_get(&pdev->dev, "vcom");
if (IS_ERR(regulator))
return PTR_ERR(regulator);
err = regulator_enable(regulator);
if (err)
return err;
hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev,
"sy7636a_temperature", regmap,
&sy7636a_chip_info, NULL);
if (IS_ERR(hwmon_dev)) {
err = PTR_ERR(hwmon_dev);
dev_err(&pdev->dev, "Unable to register hwmon device, returned %d\n", err);
return err;
}
return 0;
}
static struct platform_driver sy7636a_sensor_driver = {
.probe = sy7636a_sensor_probe,
.driver = {
.name = "sy7636a-temperature",
},
};
module_platform_driver(sy7636a_sensor_driver);
MODULE_DESCRIPTION("SY7636A sensor driver");
MODULE_LICENSE("GPL");