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");