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	long val;
 49
 50	req.channels = (1 << attr->index);
 51	req.method = TWL4030_MADC_SW2;
 52	req.func_cb = NULL;
 53	val = twl4030_madc_conversion(&req);
 54	if (val < 0)
 55		return val;
 56
 57	return sprintf(buf, "%d\n", req.rbuf[attr->index]);
 58}
 59
 60/* sysfs nodes to read individual channels from user side */
 61static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, madc_read, NULL, 0);
 62static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, madc_read, NULL, 1);
 63static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, madc_read, NULL, 2);
 64static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, madc_read, NULL, 3);
 65static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, madc_read, NULL, 4);
 66static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, madc_read, NULL, 5);
 67static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, madc_read, NULL, 6);
 68static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, madc_read, NULL, 7);
 69static SENSOR_DEVICE_ATTR(in8_input, S_IRUGO, madc_read, NULL, 8);
 70static SENSOR_DEVICE_ATTR(in9_input, S_IRUGO, madc_read, NULL, 9);
 71static SENSOR_DEVICE_ATTR(curr10_input, S_IRUGO, madc_read, NULL, 10);
 72static SENSOR_DEVICE_ATTR(in11_input, S_IRUGO, madc_read, NULL, 11);
 73static SENSOR_DEVICE_ATTR(in12_input, S_IRUGO, madc_read, NULL, 12);
 74static SENSOR_DEVICE_ATTR(in15_input, S_IRUGO, madc_read, NULL, 15);
 75
 76static struct attribute *twl4030_madc_attributes[] = {
 77	&sensor_dev_attr_in0_input.dev_attr.attr,
 78	&sensor_dev_attr_temp1_input.dev_attr.attr,
 79	&sensor_dev_attr_in2_input.dev_attr.attr,
 80	&sensor_dev_attr_in3_input.dev_attr.attr,
 81	&sensor_dev_attr_in4_input.dev_attr.attr,
 82	&sensor_dev_attr_in5_input.dev_attr.attr,
 83	&sensor_dev_attr_in6_input.dev_attr.attr,
 84	&sensor_dev_attr_in7_input.dev_attr.attr,
 85	&sensor_dev_attr_in8_input.dev_attr.attr,
 86	&sensor_dev_attr_in9_input.dev_attr.attr,
 87	&sensor_dev_attr_curr10_input.dev_attr.attr,
 88	&sensor_dev_attr_in11_input.dev_attr.attr,
 89	&sensor_dev_attr_in12_input.dev_attr.attr,
 90	&sensor_dev_attr_in15_input.dev_attr.attr,
 91	NULL
 92};
 93
 94static const struct attribute_group twl4030_madc_group = {
 95	.attrs = twl4030_madc_attributes,
 96};
 97
 98static int __devinit twl4030_madc_hwmon_probe(struct platform_device *pdev)
 99{
100	int ret;
101	struct device *hwmon;
102
103	ret = sysfs_create_group(&pdev->dev.kobj, &twl4030_madc_group);
104	if (ret)
105		goto err_sysfs;
106	hwmon = hwmon_device_register(&pdev->dev);
107	if (IS_ERR(hwmon)) {
108		dev_err(&pdev->dev, "hwmon_device_register failed.\n");
109		ret = PTR_ERR(hwmon);
110		goto err_reg;
111	}
112
113	return 0;
114
115err_reg:
116	sysfs_remove_group(&pdev->dev.kobj, &twl4030_madc_group);
117err_sysfs:
118
119	return ret;
120}
121
122static int __devexit twl4030_madc_hwmon_remove(struct platform_device *pdev)
123{
124	hwmon_device_unregister(&pdev->dev);
125	sysfs_remove_group(&pdev->dev.kobj, &twl4030_madc_group);
126
127	return 0;
128}
129
130static struct platform_driver twl4030_madc_hwmon_driver = {
131	.probe = twl4030_madc_hwmon_probe,
132	.remove = __exit_p(twl4030_madc_hwmon_remove),
133	.driver = {
134		   .name = "twl4030_madc_hwmon",
135		   .owner = THIS_MODULE,
136		   },
137};
138
139static int __init twl4030_madc_hwmon_init(void)
140{
141	return platform_driver_register(&twl4030_madc_hwmon_driver);
142}
143
144module_init(twl4030_madc_hwmon_init);
145
146static void __exit twl4030_madc_hwmon_exit(void)
147{
148	platform_driver_unregister(&twl4030_madc_hwmon_driver);
149}
150
151module_exit(twl4030_madc_hwmon_exit);
152
153MODULE_DESCRIPTION("TWL4030 ADC Hwmon driver");
154MODULE_LICENSE("GPL");
155MODULE_AUTHOR("J Keerthy");
156MODULE_ALIAS("platform:twl4030_madc_hwmon");