summaryrefslogtreecommitdiffstats
path: root/drivers/iio/light/vcnl4000.c
blob: d948c4778ba6cc98776654edb34ec1636f08f480 (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
/*
 * vcnl4000.c - Support for Vishay VCNL4000 combined ambient light and
 * proximity sensor
 *
 * Copyright 2012 Peter Meerwald <pmeerw@pmeerw.net>
 *
 * This file is subject to the terms and conditions of version 2 of
 * the GNU General Public License.  See the file COPYING in the main
 * directory of this archive for more details.
 *
 * IIO driver for VCNL4000 (7-bit I2C slave address 0x13)
 *
 * TODO:
 *   allow to adjust IR current
 *   proximity threshold and event handling
 */

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/delay.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

#define VCNL4000_DRV_NAME "vcnl4000"

#define VCNL4000_COMMAND	0x80 /* Command register */
#define VCNL4000_PROD_REV	0x81 /* Product ID and Revision ID */
#define VCNL4000_LED_CURRENT	0x83 /* IR LED current for proximity mode */
#define VCNL4000_AL_PARAM	0x84 /* Ambient light parameter register */
#define VCNL4000_AL_RESULT_HI	0x85 /* Ambient light result register, MSB */
#define VCNL4000_AL_RESULT_LO	0x86 /* Ambient light result register, LSB */
#define VCNL4000_PS_RESULT_HI	0x87 /* Proximity result register, MSB */
#define VCNL4000_PS_RESULT_LO	0x88 /* Proximity result register, LSB */
#define VCNL4000_PS_MEAS_FREQ	0x89 /* Proximity test signal frequency */
#define VCNL4000_PS_MOD_ADJ	0x8a /* Proximity modulator timing adjustment */

/* Bit masks for COMMAND register */
#define VCNL4000_AL_RDY		0x40 /* ALS data ready? */
#define VCNL4000_PS_RDY		0x20 /* proximity data ready? */
#define VCNL4000_AL_OD		0x10 /* start on-demand ALS measurement */
#define VCNL4000_PS_OD		0x08 /* start on-demand proximity measurement */

struct vcnl4000_data {
	struct i2c_client *client;
};

static const struct i2c_device_id vcnl4000_id[] = {
	{ "vcnl4000", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, vcnl4000_id);

static int vcnl4000_measure(struct vcnl4000_data *data, u8 req_mask,
				u8 rdy_mask, u8 data_reg, int *val)
{
	int tries = 20;
	__be16 buf;
	int ret;

	ret = i2c_smbus_write_byte_data(data->client, VCNL4000_COMMAND,
					req_mask);
	if (ret < 0)
		return ret;

	/* wait for data to become ready */
	while (tries--) {
		ret = i2c_smbus_read_byte_data(data->client, VCNL4000_COMMAND);
		if (ret < 0)
			return ret;
		if (ret & rdy_mask)
			break;
		msleep(20); /* measurement takes up to 100 ms */
	}

	if (tries < 0) {
		dev_err(&data->client->dev,
			"vcnl4000_measure() failed, data not ready\n");
		return -EIO;
	}

	ret = i2c_smbus_read_i2c_block_data(data->client,
		data_reg, sizeof(buf), (u8 *) &buf);
	if (ret < 0)
		return ret;

	*val = be16_to_cpu(buf);

	return 0;
}

static const struct iio_chan_spec vcnl4000_channels[] = {
	{
		.type = IIO_LIGHT,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
			BIT(IIO_CHAN_INFO_SCALE),
	}, {
		.type = IIO_PROXIMITY,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	}
};

static int vcnl4000_read_raw(struct iio_dev *indio_dev,
				struct iio_chan_spec const *chan,
				int *val, int *val2, long mask)
{
	int ret = -EINVAL;
	struct vcnl4000_data *data = iio_priv(indio_dev);

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		switch (chan->type) {
		case IIO_LIGHT:
			ret = vcnl4000_measure(data,
				VCNL4000_AL_OD, VCNL4000_AL_RDY,
				VCNL4000_AL_RESULT_HI, val);
			if (ret < 0)
				return ret;
			ret = IIO_VAL_INT;
			break;
		case IIO_PROXIMITY:
			ret = vcnl4000_measure(data,
				VCNL4000_PS_OD, VCNL4000_PS_RDY,
				VCNL4000_PS_RESULT_HI, val);
			if (ret < 0)
				return ret;
			ret = IIO_VAL_INT;
			break;
		default:
			break;
		}
		break;
	case IIO_CHAN_INFO_SCALE:
		if (chan->type == IIO_LIGHT) {
			*val = 0;
			*val2 = 250000;
			ret = IIO_VAL_INT_PLUS_MICRO;
		}
		break;
	default:
		break;
	}

	return ret;
}

static const struct iio_info vcnl4000_info = {
	.read_raw = vcnl4000_read_raw,
	.driver_module = THIS_MODULE,
};

static int vcnl4000_probe(struct i2c_client *client,
			  const struct i2c_device_id *id)
{
	struct vcnl4000_data *data;
	struct iio_dev *indio_dev;
	int ret;

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	if (!indio_dev)
		return -ENOMEM;

	data = iio_priv(indio_dev);
	i2c_set_clientdata(client, indio_dev);
	data->client = client;

	ret = i2c_smbus_read_byte_data(data->client, VCNL4000_PROD_REV);
	if (ret < 0)
		return ret;

	dev_info(&client->dev, "VCNL4000 Ambient light/proximity sensor, Prod %02x, Rev: %02x\n",
		ret >> 4, ret & 0xf);

	indio_dev->dev.parent = &client->dev;
	indio_dev->info = &vcnl4000_info;
	indio_dev->channels = vcnl4000_channels;
	indio_dev->num_channels = ARRAY_SIZE(vcnl4000_channels);
	indio_dev->name = VCNL4000_DRV_NAME;
	indio_dev->modes = INDIO_DIRECT_MODE;

	return devm_iio_device_register(&client->dev, indio_dev);
}

static struct i2c_driver vcnl4000_driver = {
	.driver = {
		.name   = VCNL4000_DRV_NAME,
		.owner  = THIS_MODULE,
	},
	.probe  = vcnl4000_probe,
	.id_table = vcnl4000_id,
};

module_i2c_driver(vcnl4000_driver);

MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("Vishay VCNL4000 proximity/ambient light sensor driver");
MODULE_LICENSE("GPL");