LXR linux/drivers/hwmon/twl4030-madc-hwmon.c

   1/*
   2 *
   3 * TWL4030 MADC Hwmon driver-This driver monitors the real time
   4 * conversion of analog signals like battery temperature,
   5 * battery type, battery level etc. User can ask for the conversion on a
   6 * particular channel using the sysfs nodes.
   7 *
   8 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
   9 * J Keerthy <j-keerthy@ti.com>
  10 *
  11 * This program is free software; you can redistribute it and/or
  12 * modify it under the terms of the GNU General Public License
  13 * version 2 as published by the Free Software Foundation.
  14 *
  15 * This program is distributed in the hope that it will be useful, but
  16 * WITHOUT ANY WARRANTY; without even the implied warranty of
  17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18 * General Public License for more details.
  19 *
  20 * You should have received a copy of the GNU General Public License
  21 * along with this program; if not, write to the Free Software
  22 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  23 * 02110-1301 USA
  24 *
  25 */
  26#include <linux/init.h>
  27#include <linux/module.h>
  28#include <linux/kernel.h>
  29#include <linux/i2c/twl.h>
  30#include <linux/device.h>
  31#include <linux/platform_device.h>
  32#include <linux/i2c/twl4030-madc.h>
  33#include <linux/hwmon.h>
  34#include <linux/hwmon-sysfs.h>
  35#include <linux/stddef.h>
  36#include <linux/sysfs.h>
  37#include <linux/err.h>
  38#include <linux/types.h>
  39
  40/*
  41 * sysfs hook function
  42 */
  43static ssize_t madc_read(struct device *dev,
  44                         struct device_attribute *devattr, char *buf)
  45{
  46        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  47        struct twl4030_madc_request req = {
  48                .channels = 1 << attr->index,
  49                .method = TWL4030_MADC_SW2,
  50                .type = TWL4030_MADC_WAIT,
  51        };
  52        long val;
  53
  54        val = twl4030_madc_conversion(&req);
  55        if (val < 0)
  56                return val;
  57
  58        return sprintf(buf, "%d\n", req.rbuf[attr->index]);
  59}
  60
  61/* sysfs nodes to read individual channels from user side */
  62static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, madc_read, NULL, 0);
  63static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, madc_read, NULL, 1);
  64static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, madc_read, NULL, 2);
  65static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, madc_read, NULL, 3);
  66static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, madc_read, NULL, 4);
  67static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, madc_read, NULL, 5);
  68static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, madc_read, NULL, 6);
  69static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, madc_read, NULL, 7);
  70static SENSOR_DEVICE_ATTR(in8_input, S_IRUGO, madc_read, NULL, 8);
  71static SENSOR_DEVICE_ATTR(in9_input, S_IRUGO, madc_read, NULL, 9);
  72static SENSOR_DEVICE_ATTR(curr10_input, S_IRUGO, madc_read, NULL, 10);
  73static SENSOR_DEVICE_ATTR(in11_input, S_IRUGO, madc_read, NULL, 11);
  74static SENSOR_DEVICE_ATTR(in12_input, S_IRUGO, madc_read, NULL, 12);
  75static SENSOR_DEVICE_ATTR(in15_input, S_IRUGO, madc_read, NULL, 15);
  76
  77static struct attribute *twl4030_madc_attributes[] = {
  78        &sensor_dev_attr_in0_input.dev_attr.attr,
  79        &sensor_dev_attr_temp1_input.dev_attr.attr,
  80        &sensor_dev_attr_in2_input.dev_attr.attr,
  81        &sensor_dev_attr_in3_input.dev_attr.attr,
  82        &sensor_dev_attr_in4_input.dev_attr.attr,
  83        &sensor_dev_attr_in5_input.dev_attr.attr,
  84        &sensor_dev_attr_in6_input.dev_attr.attr,
  85        &sensor_dev_attr_in7_input.dev_attr.attr,
  86        &sensor_dev_attr_in8_input.dev_attr.attr,
  87        &sensor_dev_attr_in9_input.dev_attr.attr,
  88        &sensor_dev_attr_curr10_input.dev_attr.attr,
  89        &sensor_dev_attr_in11_input.dev_attr.attr,
  90        &sensor_dev_attr_in12_input.dev_attr.attr,
  91        &sensor_dev_attr_in15_input.dev_attr.attr,
  92        NULL
  93};
  94
  95static const struct attribute_group twl4030_madc_group = {
  96        .attrs = twl4030_madc_attributes,
  97};
  98
  99static int twl4030_madc_hwmon_probe(struct platform_device *pdev)
 100{
 101        int ret;
 102        struct device *hwmon;
 103
 104        ret = sysfs_create_group(&pdev->dev.kobj, &twl4030_madc_group);
 105        if (ret)
 106                goto err_sysfs;
 107        hwmon = hwmon_device_register(&pdev->dev);
 108        if (IS_ERR(hwmon)) {
 109                dev_err(&pdev->dev, "hwmon_device_register failed.\n");
 110                ret = PTR_ERR(hwmon);
 111                goto err_reg;
 112        }
 113
 114        return 0;
 115
 116err_reg:
 117        sysfs_remove_group(&pdev->dev.kobj, &twl4030_madc_group);
 118err_sysfs:
 119
 120        return ret;
 121}
 122
 123static int twl4030_madc_hwmon_remove(struct platform_device *pdev)
 124{
 125        hwmon_device_unregister(&pdev->dev);
 126        sysfs_remove_group(&pdev->dev.kobj, &twl4030_madc_group);
 127
 128        return 0;
 129}
 130
 131static struct platform_driver twl4030_madc_hwmon_driver = {
 132        .probe = twl4030_madc_hwmon_probe,
 133        .remove = twl4030_madc_hwmon_remove,
 134        .driver = {
 135                   .name = "twl4030_madc_hwmon",
 136                   .owner = THIS_MODULE,
 137                   },
 138};
 139
 140module_platform_driver(twl4030_madc_hwmon_driver);
 141
 142MODULE_DESCRIPTION("TWL4030 ADC Hwmon driver");
 143MODULE_LICENSE("GPL");
 144MODULE_AUTHOR("J Keerthy");
 145MODULE_ALIAS("platform:twl4030_madc_hwmon");
 146