LXR linux/drivers/hwmon/wm8350-hwmon.c

   1/*
   2 * drivers/hwmon/wm8350-hwmon.c - Wolfson Microelectronics WM8350 PMIC
   3 *                                  hardware monitoring features.
   4 *
   5 * Copyright (C) 2009 Wolfson Microelectronics plc
   6 *
   7 * This program is free software; you can redistribute it and/or modify it
   8 * under the terms of the GNU General Public License v2 as published by the
   9 * Free Software Foundation.
  10 *
  11 * This program is distributed in the hope that it will be useful, but WITHOUT
  12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14 * more details.
  15 *
  16 * You should have received a copy of the GNU General Public License along with
  17 * this program; if not, write to the Free Software Foundation, Inc.,
  18 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  19 */
  20
  21#include <linux/kernel.h>
  22#include <linux/module.h>
  23#include <linux/err.h>
  24#include <linux/platform_device.h>
  25#include <linux/hwmon.h>
  26#include <linux/hwmon-sysfs.h>
  27
  28#include <linux/mfd/wm8350/core.h>
  29#include <linux/mfd/wm8350/comparator.h>
  30
  31static const char * const input_names[] = {
  32        [WM8350_AUXADC_USB]  = "USB",
  33        [WM8350_AUXADC_LINE] = "Line",
  34        [WM8350_AUXADC_BATT] = "Battery",
  35};
  36
  37static ssize_t show_voltage(struct device *dev,
  38                            struct device_attribute *attr, char *buf)
  39{
  40        struct wm8350 *wm8350 = dev_get_drvdata(dev);
  41        int channel = to_sensor_dev_attr(attr)->index;
  42        int val;
  43
  44        val = wm8350_read_auxadc(wm8350, channel, 0, 0) * WM8350_AUX_COEFF;
  45        val = DIV_ROUND_CLOSEST(val, 1000);
  46
  47        return sprintf(buf, "%d\n", val);
  48}
  49
  50static ssize_t show_label(struct device *dev,
  51                          struct device_attribute *attr, char *buf)
  52{
  53        int channel = to_sensor_dev_attr(attr)->index;
  54
  55        return sprintf(buf, "%s\n", input_names[channel]);
  56}
  57
  58#define WM8350_NAMED_VOLTAGE(id, name) \
  59        static SENSOR_DEVICE_ATTR(in##id##_input, S_IRUGO, show_voltage,\
  60                                  NULL, name);          \
  61        static SENSOR_DEVICE_ATTR(in##id##_label, S_IRUGO, show_label,  \
  62                                  NULL, name)
  63
  64WM8350_NAMED_VOLTAGE(0, WM8350_AUXADC_USB);
  65WM8350_NAMED_VOLTAGE(1, WM8350_AUXADC_BATT);
  66WM8350_NAMED_VOLTAGE(2, WM8350_AUXADC_LINE);
  67
  68static struct attribute *wm8350_attrs[] = {
  69        &sensor_dev_attr_in0_input.dev_attr.attr,
  70        &sensor_dev_attr_in0_label.dev_attr.attr,
  71        &sensor_dev_attr_in1_input.dev_attr.attr,
  72        &sensor_dev_attr_in1_label.dev_attr.attr,
  73        &sensor_dev_attr_in2_input.dev_attr.attr,
  74        &sensor_dev_attr_in2_label.dev_attr.attr,
  75
  76        NULL,
  77};
  78
  79ATTRIBUTE_GROUPS(wm8350);
  80
  81static int wm8350_hwmon_probe(struct platform_device *pdev)
  82{
  83        struct wm8350 *wm8350 = platform_get_drvdata(pdev);
  84        struct device *hwmon_dev;
  85
  86        hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, "wm8350",
  87                                                           wm8350,
  88                                                           wm8350_groups);
  89        return PTR_ERR_OR_ZERO(hwmon_dev);
  90}
  91
  92static struct platform_driver wm8350_hwmon_driver = {
  93        .probe = wm8350_hwmon_probe,
  94        .driver = {
  95                .name = "wm8350-hwmon",
  96        },
  97};
  98
  99module_platform_driver(wm8350_hwmon_driver);
 100
 101MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 102MODULE_DESCRIPTION("WM8350 Hardware Monitoring");
 103MODULE_LICENSE("GPL");
 104MODULE_ALIAS("platform:wm8350-hwmon");
 105