Quelle  wm831x-hwmon.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 * drivers/hwmon/wm831x-hwmon.c - Wolfson Microelectronics WM831x PMIC
 *                                hardware monitoring features.
 *
 * Copyright (C) 2009 Wolfson Microelectronics plc
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/slab.h>

#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/auxadc.h>

static const char * const input_names[] = {
 [WM831X_AUX_SYSVDD]    = "SYSVDD",
 [WM831X_AUX_USB]       = "USB",
 [WM831X_AUX_BKUP_BATT] = "Backup battery",
 [WM831X_AUX_BATT]      = "Battery",
 [WM831X_AUX_WALL]      = "WALL",
 [WM831X_AUX_CHIP_TEMP] = "PMIC",
 [WM831X_AUX_BATT_TEMP] = "Battery",
};

static ssize_t show_voltage(struct device *dev,
       struct device_attribute *attr, char *buf)
{
 struct wm831x *wm831x = dev_get_drvdata(dev);
 int channel = to_sensor_dev_attr(attr)->index;
 int ret;

 ret = wm831x_auxadc_read_uv(wm831x, channel);
 if (ret < 0)
  return ret;

 return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(ret, 1000));
}

static ssize_t show_chip_temp(struct device *dev,
         struct device_attribute *attr, char *buf)
{
 struct wm831x *wm831x = dev_get_drvdata(dev);
 int channel = to_sensor_dev_attr(attr)->index;
 int ret;

 ret = wm831x_auxadc_read(wm831x, channel);
 if (ret < 0)
  return ret;

 /* Degrees celsius = (512.18-ret) / 1.0983 */
 ret = 512180 - (ret * 1000);
 ret = DIV_ROUND_CLOSEST(ret * 10000, 10983);

 return sprintf(buf, "%d\n", ret);
}

static ssize_t show_label(struct device *dev,
     struct device_attribute *attr, char *buf)
{
 int channel = to_sensor_dev_attr(attr)->index;

 return sprintf(buf, "%s\n", input_names[channel]);
}

#define WM831X_VOLTAGE(id, name) \
 static SENSOR_DEVICE_ATTR(in##id##_input, S_IRUGO, show_voltage, \
      NULL, name)

#define WM831X_NAMED_VOLTAGE(id, name) \
 WM831X_VOLTAGE(id, name); \
 static SENSOR_DEVICE_ATTR(in##id##_label, S_IRUGO, show_label, \
      NULL, name)

WM831X_VOLTAGE(0, WM831X_AUX_AUX1);
WM831X_VOLTAGE(1, WM831X_AUX_AUX2);
WM831X_VOLTAGE(2, WM831X_AUX_AUX3);
WM831X_VOLTAGE(3, WM831X_AUX_AUX4);

WM831X_NAMED_VOLTAGE(4, WM831X_AUX_SYSVDD);
WM831X_NAMED_VOLTAGE(5, WM831X_AUX_USB);
WM831X_NAMED_VOLTAGE(6, WM831X_AUX_BATT);
WM831X_NAMED_VOLTAGE(7, WM831X_AUX_WALL);
WM831X_NAMED_VOLTAGE(8, WM831X_AUX_BKUP_BATT);

static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_chip_temp, NULL,
     WM831X_AUX_CHIP_TEMP);
static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL,
     WM831X_AUX_CHIP_TEMP);
/*
 * Report as a voltage since conversion depends on external components
 * and that's what the ABI wants.
 */
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_voltage, NULL,
     WM831X_AUX_BATT_TEMP);
static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, show_label, NULL,
     WM831X_AUX_BATT_TEMP);

static struct attribute *wm831x_attrs[] = {
 &sensor_dev_attr_in0_input.dev_attr.attr,
 &sensor_dev_attr_in1_input.dev_attr.attr,
 &sensor_dev_attr_in2_input.dev_attr.attr,
 &sensor_dev_attr_in3_input.dev_attr.attr,

 &sensor_dev_attr_in4_input.dev_attr.attr,
 &sensor_dev_attr_in4_label.dev_attr.attr,
 &sensor_dev_attr_in5_input.dev_attr.attr,
 &sensor_dev_attr_in5_label.dev_attr.attr,
 &sensor_dev_attr_in6_input.dev_attr.attr,
 &sensor_dev_attr_in6_label.dev_attr.attr,
 &sensor_dev_attr_in7_input.dev_attr.attr,
 &sensor_dev_attr_in7_label.dev_attr.attr,
 &sensor_dev_attr_in8_input.dev_attr.attr,
 &sensor_dev_attr_in8_label.dev_attr.attr,

 &sensor_dev_attr_temp1_input.dev_attr.attr,
 &sensor_dev_attr_temp1_label.dev_attr.attr,
 &sensor_dev_attr_temp2_input.dev_attr.attr,
 &sensor_dev_attr_temp2_label.dev_attr.attr,

 NULL
};

ATTRIBUTE_GROUPS(wm831x);

static int wm831x_hwmon_probe(struct platform_device *pdev)
{
 struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
 struct device *hwmon_dev;

 hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, "wm831x",
          wm831x,
          wm831x_groups);
 return PTR_ERR_OR_ZERO(hwmon_dev);
}

static struct platform_driver wm831x_hwmon_driver = {
 .probe = wm831x_hwmon_probe,
 .driver = {
  .name = "wm831x-hwmon",
 },
};

module_platform_driver(wm831x_hwmon_driver);

MODULE_AUTHOR("Mark Brown ");
MODULE_DESCRIPTION("WM831x Hardware Monitoring");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm831x-hwmon");