1
2
3
4
5
6
7
8#include <linux/module.h>
9#include <linux/slab.h>
10#include <linux/jiffies.h>
11#include <linux/i2c.h>
12#include <linux/err.h>
13
14#include <linux/iio/iio.h>
15#include <linux/iio/sysfs.h>
16#include <linux/iio/dac/max517.h>
17
18#define MAX517_DRV_NAME "max517"
19
20
21#define COMMAND_CHANNEL0 0x00
22#define COMMAND_CHANNEL1 0x01
23#define COMMAND_PD 0x08
24
25enum max517_device_ids {
26 ID_MAX517,
27 ID_MAX518,
28 ID_MAX519,
29 ID_MAX520,
30 ID_MAX521,
31};
32
33struct max517_data {
34 struct i2c_client *client;
35 unsigned short vref_mv[8];
36};
37
38
39
40
41
42
43static int max517_set_value(struct iio_dev *indio_dev,
44 long val, int channel)
45{
46 struct max517_data *data = iio_priv(indio_dev);
47 struct i2c_client *client = data->client;
48 u8 outbuf[2];
49 int res;
50
51 if (val < 0 || val > 255)
52 return -EINVAL;
53
54 outbuf[0] = channel;
55 outbuf[1] = val;
56
57 res = i2c_master_send(client, outbuf, 2);
58 if (res < 0)
59 return res;
60 else if (res != 2)
61 return -EIO;
62 else
63 return 0;
64}
65
66static int max517_read_raw(struct iio_dev *indio_dev,
67 struct iio_chan_spec const *chan,
68 int *val,
69 int *val2,
70 long m)
71{
72 struct max517_data *data = iio_priv(indio_dev);
73
74 switch (m) {
75 case IIO_CHAN_INFO_SCALE:
76
77 *val = data->vref_mv[chan->channel];
78 *val2 = 8;
79 return IIO_VAL_FRACTIONAL_LOG2;
80 default:
81 break;
82 }
83 return -EINVAL;
84}
85
86static int max517_write_raw(struct iio_dev *indio_dev,
87 struct iio_chan_spec const *chan, int val, int val2, long mask)
88{
89 int ret;
90
91 switch (mask) {
92 case IIO_CHAN_INFO_RAW:
93 ret = max517_set_value(indio_dev, val, chan->channel);
94 break;
95 default:
96 ret = -EINVAL;
97 break;
98 }
99
100 return ret;
101}
102
103static int __maybe_unused max517_suspend(struct device *dev)
104{
105 u8 outbuf = COMMAND_PD;
106
107 return i2c_master_send(to_i2c_client(dev), &outbuf, 1);
108}
109
110static int __maybe_unused max517_resume(struct device *dev)
111{
112 u8 outbuf = 0;
113
114 return i2c_master_send(to_i2c_client(dev), &outbuf, 1);
115}
116
117static SIMPLE_DEV_PM_OPS(max517_pm_ops, max517_suspend, max517_resume);
118
119static const struct iio_info max517_info = {
120 .read_raw = max517_read_raw,
121 .write_raw = max517_write_raw,
122};
123
124#define MAX517_CHANNEL(chan) { \
125 .type = IIO_VOLTAGE, \
126 .indexed = 1, \
127 .output = 1, \
128 .channel = (chan), \
129 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
130 BIT(IIO_CHAN_INFO_SCALE), \
131}
132
133static const struct iio_chan_spec max517_channels[] = {
134 MAX517_CHANNEL(0),
135 MAX517_CHANNEL(1),
136 MAX517_CHANNEL(2),
137 MAX517_CHANNEL(3),
138 MAX517_CHANNEL(4),
139 MAX517_CHANNEL(5),
140 MAX517_CHANNEL(6),
141 MAX517_CHANNEL(7),
142};
143
144static int max517_probe(struct i2c_client *client,
145 const struct i2c_device_id *id)
146{
147 struct max517_data *data;
148 struct iio_dev *indio_dev;
149 struct max517_platform_data *platform_data = client->dev.platform_data;
150 int chan;
151
152 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
153 if (!indio_dev)
154 return -ENOMEM;
155 data = iio_priv(indio_dev);
156 data->client = client;
157
158 switch (id->driver_data) {
159 case ID_MAX521:
160 indio_dev->num_channels = 8;
161 break;
162 case ID_MAX520:
163 indio_dev->num_channels = 4;
164 break;
165 case ID_MAX519:
166 case ID_MAX518:
167 indio_dev->num_channels = 2;
168 break;
169 default:
170 indio_dev->num_channels = 1;
171 break;
172 }
173 indio_dev->channels = max517_channels;
174 indio_dev->modes = INDIO_DIRECT_MODE;
175 indio_dev->info = &max517_info;
176
177
178
179
180
181 for (chan = 0; chan < indio_dev->num_channels; chan++) {
182 if (id->driver_data == ID_MAX518 || !platform_data)
183 data->vref_mv[chan] = 5000;
184 else
185 data->vref_mv[chan] = platform_data->vref_mv[chan];
186 }
187
188 return devm_iio_device_register(&client->dev, indio_dev);
189}
190
191static const struct i2c_device_id max517_id[] = {
192 { "max517", ID_MAX517 },
193 { "max518", ID_MAX518 },
194 { "max519", ID_MAX519 },
195 { "max520", ID_MAX520 },
196 { "max521", ID_MAX521 },
197 { }
198};
199MODULE_DEVICE_TABLE(i2c, max517_id);
200
201static struct i2c_driver max517_driver = {
202 .driver = {
203 .name = MAX517_DRV_NAME,
204 .pm = &max517_pm_ops,
205 },
206 .probe = max517_probe,
207 .id_table = max517_id,
208};
209module_i2c_driver(max517_driver);
210
211MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
212MODULE_DESCRIPTION("MAX517/518/519/520/521 8-bit DAC");
213MODULE_LICENSE("GPL");
214
