/*
* drivers/hwmon/wm831x-hwmon.c - Wolfson Microelectronics WM831x PMIC
* hardware monitoring features.
*
* Copyright (C) 2009 Wolfson Microelectronics plc
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License v2 as published by the
* Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#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>
struct wm831x_hwmon {
struct wm831x *wm831x;
struct device *classdev;
};
static ssize_t show_name(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "wm831x\n");
}
static const char *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_hwmon *hwmon = dev_get_drvdata(dev);
int channel = to_sensor_dev_attr(attr)->index;
int ret;
ret = wm831x_auxadc_read_uv(hwmon->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_hwmon *hwmon = dev_get_drvdata(dev);
int channel = to_sensor_dev_attr(attr)->index;
int ret;
ret = wm831x_auxadc_read(hwmon->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)
static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
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_attributes[] = {
&dev_attr_name.attr,
&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
};
static const struct attribute_group wm831x_attr_group = {
.attrs = wm831x_attributes,
};
static int __devinit wm831x_hwmon_probe(struct platform_device *pdev)
{
struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
struct wm831x_hwmon *hwmon;
int ret;
hwmon = kzalloc(sizeof(struct wm831x_hwmon), GFP_KERNEL);
if (!hwmon)
return -ENOMEM;
hwmon->wm831x = wm831x;
ret = sysfs_create_group(&pdev->dev.kobj, &wm831x_attr_group);
if (ret)
goto err;
hwmon->classdev = hwmon_device_register(&pdev->dev);
if (IS_ERR(hwmon->classdev)) {
ret = PTR_ERR(hwmon->classdev);
goto err_sysfs;
}
platform_set_drvdata(pdev, hwmon);
return 0;
err_sysfs:
sysfs_remove_group(&pdev->dev.kobj, &wm831x_attr_group);
err:
kfree(hwmon);
return ret;
}
static int __devexit wm831x_hwmon_remove(struct platform_device *pdev)
{
struct wm831x_hwmon *hwmon = platform_get_drvdata(pdev);
hwmon_device_unregister(hwmon->classdev);
sysfs_remove_group(&pdev->dev.kobj, &wm831x_attr_group);
platform_set_drvdata(pdev, NULL);
kfree(hwmon);
return 0;
}
static struct platform_driver wm831x_hwmon_driver = {
.probe = wm831x_hwmon_probe,
.remove = __devexit_p(wm831x_hwmon_remove),
.driver = {
.name = "wm831x-hwmon",
.owner = THIS_MODULE,
},
};
static int __init wm831x_hwmon_init(void)
{
return platform_driver_register(&wm831x_hwmon_driver);
}
module_init(wm831x_hwmon_init);
static void __exit wm831x_hwmon_exit(void)
{
platform_driver_unregister(&wm831x_hwmon_driver);
}
module_exit(wm831x_hwmon_exit);
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("WM831x Hardware Monitoring");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm831x-hwmon");