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16#include <linux/module.h>
17#include <linux/init.h>
18#include <linux/i2c.h>
19
20#include <linux/iio/iio.h>
21#include <linux/iio/sysfs.h>
22
23#define AL3320A_DRV_NAME "al3320a"
24
25#define AL3320A_REG_CONFIG 0x00
26#define AL3320A_REG_STATUS 0x01
27#define AL3320A_REG_INT 0x02
28#define AL3320A_REG_WAIT 0x06
29#define AL3320A_REG_CONFIG_RANGE 0x07
30#define AL3320A_REG_PERSIST 0x08
31#define AL3320A_REG_MEAN_TIME 0x09
32#define AL3320A_REG_ADUMMY 0x0A
33#define AL3320A_REG_DATA_LOW 0x22
34
35#define AL3320A_REG_LOW_THRESH_LOW 0x30
36#define AL3320A_REG_LOW_THRESH_HIGH 0x31
37#define AL3320A_REG_HIGH_THRESH_LOW 0x32
38#define AL3320A_REG_HIGH_THRESH_HIGH 0x33
39
40#define AL3320A_CONFIG_DISABLE 0x00
41#define AL3320A_CONFIG_ENABLE 0x01
42
43#define AL3320A_GAIN_SHIFT 1
44#define AL3320A_GAIN_MASK (BIT(2) | BIT(1))
45
46
47#define AL3320A_DEFAULT_MEAN_TIME 4
48#define AL3320A_DEFAULT_WAIT_TIME 0
49
50#define AL3320A_SCALE_AVAILABLE "0.512 0.128 0.032 0.01"
51
52enum al3320a_range {
53 AL3320A_RANGE_1,
54 AL3320A_RANGE_2,
55 AL3320A_RANGE_3,
56 AL3320A_RANGE_4
57};
58
59static const int al3320a_scales[][2] = {
60 {0, 512000}, {0, 128000}, {0, 32000}, {0, 10000}
61};
62
63struct al3320a_data {
64 struct i2c_client *client;
65};
66
67static const struct iio_chan_spec al3320a_channels[] = {
68 {
69 .type = IIO_LIGHT,
70 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
71 BIT(IIO_CHAN_INFO_SCALE),
72 }
73};
74
75static IIO_CONST_ATTR(in_illuminance_scale_available, AL3320A_SCALE_AVAILABLE);
76
77static struct attribute *al3320a_attributes[] = {
78 &iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
79 NULL,
80};
81
82static const struct attribute_group al3320a_attribute_group = {
83 .attrs = al3320a_attributes,
84};
85
86static int al3320a_init(struct al3320a_data *data)
87{
88 int ret;
89
90
91 ret = i2c_smbus_write_byte_data(data->client, AL3320A_REG_CONFIG,
92 AL3320A_CONFIG_ENABLE);
93 if (ret < 0)
94 return ret;
95
96 ret = i2c_smbus_write_byte_data(data->client, AL3320A_REG_CONFIG_RANGE,
97 AL3320A_RANGE_3 << AL3320A_GAIN_SHIFT);
98 if (ret < 0)
99 return ret;
100
101 ret = i2c_smbus_write_byte_data(data->client, AL3320A_REG_MEAN_TIME,
102 AL3320A_DEFAULT_MEAN_TIME);
103 if (ret < 0)
104 return ret;
105
106 ret = i2c_smbus_write_byte_data(data->client, AL3320A_REG_WAIT,
107 AL3320A_DEFAULT_WAIT_TIME);
108 if (ret < 0)
109 return ret;
110
111 return 0;
112}
113
114static int al3320a_read_raw(struct iio_dev *indio_dev,
115 struct iio_chan_spec const *chan, int *val,
116 int *val2, long mask)
117{
118 struct al3320a_data *data = iio_priv(indio_dev);
119 int ret;
120
121 switch (mask) {
122 case IIO_CHAN_INFO_RAW:
123
124
125
126
127
128 ret = i2c_smbus_read_word_data(data->client,
129 AL3320A_REG_DATA_LOW);
130 if (ret < 0)
131 return ret;
132 *val = ret;
133 return IIO_VAL_INT;
134 case IIO_CHAN_INFO_SCALE:
135 ret = i2c_smbus_read_byte_data(data->client,
136 AL3320A_REG_CONFIG_RANGE);
137 if (ret < 0)
138 return ret;
139
140 ret = (ret & AL3320A_GAIN_MASK) >> AL3320A_GAIN_SHIFT;
141 *val = al3320a_scales[ret][0];
142 *val2 = al3320a_scales[ret][1];
143
144 return IIO_VAL_INT_PLUS_MICRO;
145 }
146 return -EINVAL;
147}
148
149static int al3320a_write_raw(struct iio_dev *indio_dev,
150 struct iio_chan_spec const *chan, int val,
151 int val2, long mask)
152{
153 struct al3320a_data *data = iio_priv(indio_dev);
154 int i;
155
156 switch (mask) {
157 case IIO_CHAN_INFO_SCALE:
158 for (i = 0; i < ARRAY_SIZE(al3320a_scales); i++) {
159 if (val == al3320a_scales[i][0] &&
160 val2 == al3320a_scales[i][1])
161 return i2c_smbus_write_byte_data(data->client,
162 AL3320A_REG_CONFIG_RANGE,
163 i << AL3320A_GAIN_SHIFT);
164 }
165 break;
166 }
167 return -EINVAL;
168}
169
170static const struct iio_info al3320a_info = {
171 .read_raw = al3320a_read_raw,
172 .write_raw = al3320a_write_raw,
173 .attrs = &al3320a_attribute_group,
174};
175
176static int al3320a_probe(struct i2c_client *client,
177 const struct i2c_device_id *id)
178{
179 struct al3320a_data *data;
180 struct iio_dev *indio_dev;
181 int ret;
182
183 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
184 if (!indio_dev)
185 return -ENOMEM;
186
187 data = iio_priv(indio_dev);
188 i2c_set_clientdata(client, indio_dev);
189 data->client = client;
190
191 indio_dev->dev.parent = &client->dev;
192 indio_dev->info = &al3320a_info;
193 indio_dev->name = AL3320A_DRV_NAME;
194 indio_dev->channels = al3320a_channels;
195 indio_dev->num_channels = ARRAY_SIZE(al3320a_channels);
196 indio_dev->modes = INDIO_DIRECT_MODE;
197
198 ret = al3320a_init(data);
199 if (ret < 0) {
200 dev_err(&client->dev, "al3320a chip init failed\n");
201 return ret;
202 }
203 return devm_iio_device_register(&client->dev, indio_dev);
204}
205
206static int al3320a_remove(struct i2c_client *client)
207{
208 return i2c_smbus_write_byte_data(client, AL3320A_REG_CONFIG,
209 AL3320A_CONFIG_DISABLE);
210}
211
212static const struct i2c_device_id al3320a_id[] = {
213 {"al3320a", 0},
214 {}
215};
216MODULE_DEVICE_TABLE(i2c, al3320a_id);
217
218static struct i2c_driver al3320a_driver = {
219 .driver = {
220 .name = AL3320A_DRV_NAME,
221 },
222 .probe = al3320a_probe,
223 .remove = al3320a_remove,
224 .id_table = al3320a_id,
225};
226
227module_i2c_driver(al3320a_driver);
228
229MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
230MODULE_DESCRIPTION("AL3320A Ambient Light Sensor driver");
231MODULE_LICENSE("GPL v2");
232
