drivers/hwmon/wm831x-hwmon.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * drivers/hwmon/wm831x-hwmon.c - Wolfson Microelectronics WM831x PMIC
0004  *                                hardware monitoring features.
0005  *
0006  * Copyright (C) 2009 Wolfson Microelectronics plc
0007  */
0008
0009 #include <linux/kernel.h>
0010 #include <linux/module.h>
0011 #include <linux/platform_device.h>
0012 #include <linux/err.h>
0013 #include <linux/hwmon.h>
0014 #include <linux/hwmon-sysfs.h>
0015 #include <linux/slab.h>
0016
0017 #include <linux/mfd/wm831x/core.h>
0018 #include <linux/mfd/wm831x/auxadc.h>
0019
0020 static const char * const input_names[] = {
0021     [WM831X_AUX_SYSVDD]    = "SYSVDD",
0022     [WM831X_AUX_USB]       = "USB",
0023     [WM831X_AUX_BKUP_BATT] = "Backup battery",
0024     [WM831X_AUX_BATT]      = "Battery",
0025     [WM831X_AUX_WALL]      = "WALL",
0026     [WM831X_AUX_CHIP_TEMP] = "PMIC",
0027     [WM831X_AUX_BATT_TEMP] = "Battery",
0028 };
0029
0030 static ssize_t show_voltage(struct device *dev,
0031                 struct device_attribute *attr, char *buf)
0032 {
0033     struct wm831x *wm831x = dev_get_drvdata(dev);
0034     int channel = to_sensor_dev_attr(attr)->index;
0035     int ret;
0036
0037     ret = wm831x_auxadc_read_uv(wm831x, channel);
0038     if (ret < 0)
0039         return ret;
0040
0041     return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(ret, 1000));
0042 }
0043
0044 static ssize_t show_chip_temp(struct device *dev,
0045                   struct device_attribute *attr, char *buf)
0046 {
0047     struct wm831x *wm831x = dev_get_drvdata(dev);
0048     int channel = to_sensor_dev_attr(attr)->index;
0049     int ret;
0050
0051     ret = wm831x_auxadc_read(wm831x, channel);
0052     if (ret < 0)
0053         return ret;
0054
0055     /* Degrees celsius = (512.18-ret) / 1.0983 */
0056     ret = 512180 - (ret * 1000);
0057     ret = DIV_ROUND_CLOSEST(ret * 10000, 10983);
0058
0059     return sprintf(buf, "%d\n", ret);
0060 }
0061
0062 static ssize_t show_label(struct device *dev,
0063               struct device_attribute *attr, char *buf)
0064 {
0065     int channel = to_sensor_dev_attr(attr)->index;
0066
0067     return sprintf(buf, "%s\n", input_names[channel]);
0068 }
0069
0070 #define WM831X_VOLTAGE(id, name) \
0071     static SENSOR_DEVICE_ATTR(in##id##_input, S_IRUGO, show_voltage, \
0072                   NULL, name)
0073
0074 #define WM831X_NAMED_VOLTAGE(id, name) \
0075     WM831X_VOLTAGE(id, name); \
0076     static SENSOR_DEVICE_ATTR(in##id##_label, S_IRUGO, show_label,  \
0077                   NULL, name)
0078
0079 WM831X_VOLTAGE(0, WM831X_AUX_AUX1);
0080 WM831X_VOLTAGE(1, WM831X_AUX_AUX2);
0081 WM831X_VOLTAGE(2, WM831X_AUX_AUX3);
0082 WM831X_VOLTAGE(3, WM831X_AUX_AUX4);
0083
0084 WM831X_NAMED_VOLTAGE(4, WM831X_AUX_SYSVDD);
0085 WM831X_NAMED_VOLTAGE(5, WM831X_AUX_USB);
0086 WM831X_NAMED_VOLTAGE(6, WM831X_AUX_BATT);
0087 WM831X_NAMED_VOLTAGE(7, WM831X_AUX_WALL);
0088 WM831X_NAMED_VOLTAGE(8, WM831X_AUX_BKUP_BATT);
0089
0090 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_chip_temp, NULL,
0091               WM831X_AUX_CHIP_TEMP);
0092 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL,
0093               WM831X_AUX_CHIP_TEMP);
0094 /*
0095  * Report as a voltage since conversion depends on external components
0096  * and that's what the ABI wants.
0097  */
0098 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_voltage, NULL,
0099               WM831X_AUX_BATT_TEMP);
0100 static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, show_label, NULL,
0101               WM831X_AUX_BATT_TEMP);
0102
0103 static struct attribute *wm831x_attrs[] = {
0104     &sensor_dev_attr_in0_input.dev_attr.attr,
0105     &sensor_dev_attr_in1_input.dev_attr.attr,
0106     &sensor_dev_attr_in2_input.dev_attr.attr,
0107     &sensor_dev_attr_in3_input.dev_attr.attr,
0108
0109     &sensor_dev_attr_in4_input.dev_attr.attr,
0110     &sensor_dev_attr_in4_label.dev_attr.attr,
0111     &sensor_dev_attr_in5_input.dev_attr.attr,
0112     &sensor_dev_attr_in5_label.dev_attr.attr,
0113     &sensor_dev_attr_in6_input.dev_attr.attr,
0114     &sensor_dev_attr_in6_label.dev_attr.attr,
0115     &sensor_dev_attr_in7_input.dev_attr.attr,
0116     &sensor_dev_attr_in7_label.dev_attr.attr,
0117     &sensor_dev_attr_in8_input.dev_attr.attr,
0118     &sensor_dev_attr_in8_label.dev_attr.attr,
0119
0120     &sensor_dev_attr_temp1_input.dev_attr.attr,
0121     &sensor_dev_attr_temp1_label.dev_attr.attr,
0122     &sensor_dev_attr_temp2_input.dev_attr.attr,
0123     &sensor_dev_attr_temp2_label.dev_attr.attr,
0124
0125     NULL
0126 };
0127
0128 ATTRIBUTE_GROUPS(wm831x);
0129
0130 static int wm831x_hwmon_probe(struct platform_device *pdev)
0131 {
0132     struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
0133     struct device *hwmon_dev;
0134
0135     hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, "wm831x",
0136                                wm831x,
0137                                wm831x_groups);
0138     return PTR_ERR_OR_ZERO(hwmon_dev);
0139 }
0140
0141 static struct platform_driver wm831x_hwmon_driver = {
0142     .probe = wm831x_hwmon_probe,
0143     .driver = {
0144         .name = "wm831x-hwmon",
0145     },
0146 };
0147
0148 module_platform_driver(wm831x_hwmon_driver);
0149
0150 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
0151 MODULE_DESCRIPTION("WM831x Hardware Monitoring");
0152 MODULE_LICENSE("GPL");
0153 MODULE_ALIAS("platform:wm831x-hwmon");