aboutsummaryrefslogtreecommitdiff
path: root/drivers/hwmon/wm831x-hwmon.c
blob: 9b598ed26020563978f1142840c4b6a5f0ecad77 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
/*
 * drivers/hwmon/wm831x-hwmon.c - Wolfson Microelectronics WM831x PMIC
 *                                hardware monitoring features.
 *
 * Copyright (C) 2009 Wolfson Microelectronics plc
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License v2 as published by the
 * Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/slab.h>

#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/auxadc.h>

struct wm831x_hwmon {
	struct wm831x *wm831x;
	struct device *classdev;
};

static ssize_t show_name(struct device *dev,
			 struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "wm831x\n");
}

static const char *input_names[] = {
	[WM831X_AUX_SYSVDD]    = "SYSVDD",
	[WM831X_AUX_USB]       = "USB",
	[WM831X_AUX_BKUP_BATT] = "Backup battery",
	[WM831X_AUX_BATT]      = "Battery",
	[WM831X_AUX_WALL]      = "WALL",
	[WM831X_AUX_CHIP_TEMP] = "PMIC",
	[WM831X_AUX_BATT_TEMP] = "Battery",
};


static ssize_t show_voltage(struct device *dev,
			    struct device_attribute *attr, char *buf)
{
	struct wm831x_hwmon *hwmon = dev_get_drvdata(dev);
	int channel = to_sensor_dev_attr(attr)->index;
	int ret;

	ret = wm831x_auxadc_read_uv(hwmon->wm831x, channel);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(ret, 1000));
}

static ssize_t show_chip_temp(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct wm831x_hwmon *hwmon = dev_get_drvdata(dev);
	int channel = to_sensor_dev_attr(attr)->index;
	int ret;

	ret = wm831x_auxadc_read(hwmon->wm831x, channel);
	if (ret < 0)
		return ret;

	/* Degrees celsius = (512.18-ret) / 1.0983 */
	ret = 512180 - (ret * 1000);
	ret = DIV_ROUND_CLOSEST(ret * 10000, 10983);

	return sprintf(buf, "%d\n", ret);
}

static ssize_t show_label(struct device *dev,
			  struct device_attribute *attr, char *buf)
{
	int channel = to_sensor_dev_attr(attr)->index;

	return sprintf(buf, "%s\n", input_names[channel]);
}

#define WM831X_VOLTAGE(id, name) \
	static SENSOR_DEVICE_ATTR(in##id##_input, S_IRUGO, show_voltage, \
				  NULL, name)

#define WM831X_NAMED_VOLTAGE(id, name) \
	WM831X_VOLTAGE(id, name); \
	static SENSOR_DEVICE_ATTR(in##id##_label, S_IRUGO, show_label,	\
				  NULL, name)

static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);

WM831X_VOLTAGE(0, WM831X_AUX_AUX1);
WM831X_VOLTAGE(1, WM831X_AUX_AUX2);
WM831X_VOLTAGE(2, WM831X_AUX_AUX3);
WM831X_VOLTAGE(3, WM831X_AUX_AUX4);

WM831X_NAMED_VOLTAGE(4, WM831X_AUX_SYSVDD);
WM831X_NAMED_VOLTAGE(5, WM831X_AUX_USB);
WM831X_NAMED_VOLTAGE(6, WM831X_AUX_BATT);
WM831X_NAMED_VOLTAGE(7, WM831X_AUX_WALL);
WM831X_NAMED_VOLTAGE(8, WM831X_AUX_BKUP_BATT);

static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_chip_temp, NULL,
			  WM831X_AUX_CHIP_TEMP);
static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL,
			  WM831X_AUX_CHIP_TEMP);
/* Report as a voltage since conversion depends on external components
 * and that's what the ABI wants. */
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_voltage, NULL,
			  WM831X_AUX_BATT_TEMP);
static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, show_label, NULL,
			  WM831X_AUX_BATT_TEMP);

static struct attribute *wm831x_attributes[] = {
	&dev_attr_name.attr,

	&sensor_dev_attr_in0_input.dev_attr.attr,
	&sensor_dev_attr_in1_input.dev_attr.attr,
	&sensor_dev_attr_in2_input.dev_attr.attr,
	&sensor_dev_attr_in3_input.dev_attr.attr,

	&sensor_dev_attr_in4_input.dev_attr.attr,
	&sensor_dev_attr_in4_label.dev_attr.attr,
	&sensor_dev_attr_in5_input.dev_attr.attr,
	&sensor_dev_attr_in5_label.dev_attr.attr,
	&sensor_dev_attr_in6_input.dev_attr.attr,
	&sensor_dev_attr_in6_label.dev_attr.attr,
	&sensor_dev_attr_in7_input.dev_attr.attr,
	&sensor_dev_attr_in7_label.dev_attr.attr,
	&sensor_dev_attr_in8_input.dev_attr.attr,
	&sensor_dev_attr_in8_label.dev_attr.attr,

	&sensor_dev_attr_temp1_input.dev_attr.attr,
	&sensor_dev_attr_temp1_label.dev_attr.attr,
	&sensor_dev_attr_temp2_input.dev_attr.attr,
	&sensor_dev_attr_temp2_label.dev_attr.attr,

	NULL
};

static const struct attribute_group wm831x_attr_group = {
	.attrs	= wm831x_attributes,
};

static int __devinit wm831x_hwmon_probe(struct platform_device *pdev)
{
	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
	struct wm831x_hwmon *hwmon;
	int ret;

	hwmon = kzalloc(sizeof(struct wm831x_hwmon), GFP_KERNEL);
	if (!hwmon)
		return -ENOMEM;

	hwmon->wm831x = wm831x;

	ret = sysfs_create_group(&pdev->dev.kobj, &wm831x_attr_group);
	if (ret)
		goto err;

	hwmon->classdev = hwmon_device_register(&pdev->dev);
	if (IS_ERR(hwmon->classdev)) {
		ret = PTR_ERR(hwmon->classdev);
		goto err_sysfs;
	}

	platform_set_drvdata(pdev, hwmon);

	return 0;

err_sysfs:
	sysfs_remove_group(&pdev->dev.kobj, &wm831x_attr_group);
err:
	kfree(hwmon);
	return ret;
}

static int __devexit wm831x_hwmon_remove(struct platform_device *pdev)
{
	struct wm831x_hwmon *hwmon = platform_get_drvdata(pdev);

	hwmon_device_unregister(hwmon->classdev);
	sysfs_remove_group(&pdev->dev.kobj, &wm831x_attr_group);
	platform_set_drvdata(pdev, NULL);
	kfree(hwmon);

	return 0;
}

static struct platform_driver wm831x_hwmon_driver = {
	.probe = wm831x_hwmon_probe,
	.remove = __devexit_p(wm831x_hwmon_remove),
	.driver = {
		.name = "wm831x-hwmon",
		.owner = THIS_MODULE,
	},
};

module_platform_driver(wm831x_hwmon_driver);

MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("WM831x Hardware Monitoring");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm831x-hwmon");