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
  31 static const char * const input_names[] = {
  32         [WM8350_AUXADC_USB]  = "USB",
  33         [WM8350_AUXADC_LINE] = "Line",
  34         [WM8350_AUXADC_BATT] = "Battery",
  35 };
  36
  37 static 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
  50 static 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
  64 WM8350_NAMED_VOLTAGE(0, WM8350_AUXADC_USB);
  65 WM8350_NAMED_VOLTAGE(1, WM8350_AUXADC_BATT);
  66 WM8350_NAMED_VOLTAGE(2, WM8350_AUXADC_LINE);
  67
  68 static 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
  79 ATTRIBUTE_GROUPS(wm8350);
  80
  81 static 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
  92 static struct platform_driver wm8350_hwmon_driver = {
  93         .probe = wm8350_hwmon_probe,
  94         .driver = {
  95                 .name = "wm8350-hwmon",
  96         },
  97 };
  98
  99 module_platform_driver(wm8350_hwmon_driver);
 100
 101 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 102 MODULE_DESCRIPTION("WM8350 Hardware Monitoring");
 103 MODULE_LICENSE("GPL");
 104 MODULE_ALIAS("platform:wm8350-hwmon");