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9#include <linux/err.h>
10#include <linux/i2c.h>
11#include <linux/module.h>
12
13#include <linux/iio/iio.h>
14#include <linux/regulator/consumer.h>
15
16struct adc081c {
17 struct i2c_client *i2c;
18 struct regulator *ref;
19};
20
21#define REG_CONV_RES 0x00
22
23static int adc081c_read_raw(struct iio_dev *iio,
24 struct iio_chan_spec const *channel, int *value,
25 int *shift, long mask)
26{
27 struct adc081c *adc = iio_priv(iio);
28 int err;
29
30 switch (mask) {
31 case IIO_CHAN_INFO_RAW:
32 err = i2c_smbus_read_word_swapped(adc->i2c, REG_CONV_RES);
33 if (err < 0)
34 return err;
35
36 *value = (err >> 4) & 0xff;
37 return IIO_VAL_INT;
38
39 case IIO_CHAN_INFO_SCALE:
40 err = regulator_get_voltage(adc->ref);
41 if (err < 0)
42 return err;
43
44 *value = err / 1000;
45 *shift = 8;
46
47 return IIO_VAL_FRACTIONAL_LOG2;
48
49 default:
50 break;
51 }
52
53 return -EINVAL;
54}
55
56static const struct iio_chan_spec adc081c_channel = {
57 .type = IIO_VOLTAGE,
58 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
59 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
60};
61
62static const struct iio_info adc081c_info = {
63 .read_raw = adc081c_read_raw,
64 .driver_module = THIS_MODULE,
65};
66
67static int adc081c_probe(struct i2c_client *client,
68 const struct i2c_device_id *id)
69{
70 struct iio_dev *iio;
71 struct adc081c *adc;
72 int err;
73
74 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
75 return -ENODEV;
76
77 iio = iio_device_alloc(sizeof(*adc));
78 if (!iio)
79 return -ENOMEM;
80
81 adc = iio_priv(iio);
82 adc->i2c = client;
83
84 adc->ref = regulator_get(&client->dev, "vref");
85 if (IS_ERR(adc->ref)) {
86 err = PTR_ERR(adc->ref);
87 goto iio_free;
88 }
89
90 err = regulator_enable(adc->ref);
91 if (err < 0)
92 goto regulator_put;
93
94 iio->dev.parent = &client->dev;
95 iio->name = dev_name(&client->dev);
96 iio->modes = INDIO_DIRECT_MODE;
97 iio->info = &adc081c_info;
98
99 iio->channels = &adc081c_channel;
100 iio->num_channels = 1;
101
102 err = iio_device_register(iio);
103 if (err < 0)
104 goto regulator_disable;
105
106 i2c_set_clientdata(client, iio);
107
108 return 0;
109
110regulator_disable:
111 regulator_disable(adc->ref);
112regulator_put:
113 regulator_put(adc->ref);
114iio_free:
115 iio_device_free(iio);
116
117 return err;
118}
119
120static int adc081c_remove(struct i2c_client *client)
121{
122 struct iio_dev *iio = i2c_get_clientdata(client);
123 struct adc081c *adc = iio_priv(iio);
124
125 iio_device_unregister(iio);
126 regulator_disable(adc->ref);
127 regulator_put(adc->ref);
128 iio_device_free(iio);
129
130 return 0;
131}
132
133static const struct i2c_device_id adc081c_id[] = {
134 { "adc081c", 0 },
135 { }
136};
137MODULE_DEVICE_TABLE(i2c, adc081c_id);
138
139#ifdef CONFIG_OF
140static const struct of_device_id adc081c_of_match[] = {
141 { .compatible = "ti,adc081c" },
142 { }
143};
144MODULE_DEVICE_TABLE(of, adc081c_of_match);
145#endif
146
147static struct i2c_driver adc081c_driver = {
148 .driver = {
149 .name = "adc081c",
150 .owner = THIS_MODULE,
151 .of_match_table = of_match_ptr(adc081c_of_match),
152 },
153 .probe = adc081c_probe,
154 .remove = adc081c_remove,
155 .id_table = adc081c_id,
156};
157module_i2c_driver(adc081c_driver);
158
159MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
160MODULE_DESCRIPTION("Texas Instruments ADC081C021/027 driver");
161MODULE_LICENSE("GPL v2");
162
