]>
Commit | Line | Data |
---|---|---|
2edbd295 MR |
1 | /* |
2 | * tpl0102.c - Support for Texas Instruments digital potentiometers | |
3 | * | |
4 | * Copyright (C) 2016 Matt Ranostay <mranostay@gmail.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * TODO: enable/disable hi-z output control | |
17 | */ | |
18 | ||
19 | #include <linux/module.h> | |
20 | #include <linux/i2c.h> | |
21 | #include <linux/regmap.h> | |
22 | #include <linux/iio/iio.h> | |
23 | ||
24 | struct tpl0102_cfg { | |
25 | int wipers; | |
26 | int max_pos; | |
27 | int kohms; | |
28 | }; | |
29 | ||
30 | enum tpl0102_type { | |
31 | CAT5140_503, | |
32 | CAT5140_104, | |
33 | TPL0102_104, | |
34 | TPL0401_103, | |
35 | }; | |
36 | ||
37 | static const struct tpl0102_cfg tpl0102_cfg[] = { | |
38 | /* on-semiconductor parts */ | |
39 | [CAT5140_503] = { .wipers = 1, .max_pos = 256, .kohms = 50, }, | |
40 | [CAT5140_104] = { .wipers = 1, .max_pos = 256, .kohms = 100, }, | |
41 | /* ti parts */ | |
42 | [TPL0102_104] = { .wipers = 2, .max_pos = 256, .kohms = 100 }, | |
43 | [TPL0401_103] = { .wipers = 1, .max_pos = 128, .kohms = 10, }, | |
44 | }; | |
45 | ||
46 | struct tpl0102_data { | |
47 | struct regmap *regmap; | |
48 | unsigned long devid; | |
49 | }; | |
50 | ||
51 | static const struct regmap_config tpl0102_regmap_config = { | |
52 | .reg_bits = 8, | |
53 | .val_bits = 8, | |
54 | }; | |
55 | ||
56 | #define TPL0102_CHANNEL(ch) { \ | |
57 | .type = IIO_RESISTANCE, \ | |
58 | .indexed = 1, \ | |
59 | .output = 1, \ | |
60 | .channel = (ch), \ | |
61 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ | |
62 | .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ | |
63 | } | |
64 | ||
65 | static const struct iio_chan_spec tpl0102_channels[] = { | |
66 | TPL0102_CHANNEL(0), | |
67 | TPL0102_CHANNEL(1), | |
68 | }; | |
69 | ||
70 | static int tpl0102_read_raw(struct iio_dev *indio_dev, | |
71 | struct iio_chan_spec const *chan, | |
72 | int *val, int *val2, long mask) | |
73 | { | |
74 | struct tpl0102_data *data = iio_priv(indio_dev); | |
75 | ||
76 | switch (mask) { | |
77 | case IIO_CHAN_INFO_RAW: { | |
78 | int ret = regmap_read(data->regmap, chan->channel, val); | |
79 | ||
80 | return ret ? ret : IIO_VAL_INT; | |
81 | } | |
82 | case IIO_CHAN_INFO_SCALE: | |
83 | *val = 1000 * tpl0102_cfg[data->devid].kohms; | |
84 | *val2 = tpl0102_cfg[data->devid].max_pos; | |
85 | return IIO_VAL_FRACTIONAL; | |
86 | } | |
87 | ||
88 | return -EINVAL; | |
89 | } | |
90 | ||
91 | static int tpl0102_write_raw(struct iio_dev *indio_dev, | |
92 | struct iio_chan_spec const *chan, | |
93 | int val, int val2, long mask) | |
94 | { | |
95 | struct tpl0102_data *data = iio_priv(indio_dev); | |
96 | ||
97 | if (mask != IIO_CHAN_INFO_RAW) | |
98 | return -EINVAL; | |
99 | ||
100 | if (val >= tpl0102_cfg[data->devid].max_pos || val < 0) | |
101 | return -EINVAL; | |
102 | ||
103 | return regmap_write(data->regmap, chan->channel, val); | |
104 | } | |
105 | ||
106 | static const struct iio_info tpl0102_info = { | |
107 | .read_raw = tpl0102_read_raw, | |
108 | .write_raw = tpl0102_write_raw, | |
109 | .driver_module = THIS_MODULE, | |
110 | }; | |
111 | ||
112 | static int tpl0102_probe(struct i2c_client *client, | |
113 | const struct i2c_device_id *id) | |
114 | { | |
115 | struct device *dev = &client->dev; | |
116 | struct tpl0102_data *data; | |
117 | struct iio_dev *indio_dev; | |
118 | ||
2edbd295 MR |
119 | indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); |
120 | if (!indio_dev) | |
121 | return -ENOMEM; | |
122 | data = iio_priv(indio_dev); | |
123 | i2c_set_clientdata(client, indio_dev); | |
124 | ||
125 | data->devid = id->driver_data; | |
126 | data->regmap = devm_regmap_init_i2c(client, &tpl0102_regmap_config); | |
127 | if (IS_ERR(data->regmap)) { | |
128 | dev_err(dev, "regmap initialization failed\n"); | |
129 | return PTR_ERR(data->regmap); | |
130 | } | |
131 | ||
132 | indio_dev->dev.parent = dev; | |
133 | indio_dev->info = &tpl0102_info; | |
134 | indio_dev->channels = tpl0102_channels; | |
135 | indio_dev->num_channels = tpl0102_cfg[data->devid].wipers; | |
136 | indio_dev->name = client->name; | |
137 | ||
138 | return devm_iio_device_register(dev, indio_dev); | |
139 | } | |
140 | ||
141 | static const struct i2c_device_id tpl0102_id[] = { | |
142 | { "cat5140-503", CAT5140_503 }, | |
143 | { "cat5140-104", CAT5140_104 }, | |
144 | { "tpl0102-104", TPL0102_104 }, | |
145 | { "tpl0401-103", TPL0401_103 }, | |
146 | {} | |
147 | }; | |
148 | MODULE_DEVICE_TABLE(i2c, tpl0102_id); | |
149 | ||
150 | static struct i2c_driver tpl0102_driver = { | |
151 | .driver = { | |
152 | .name = "tpl0102", | |
153 | }, | |
154 | .probe = tpl0102_probe, | |
155 | .id_table = tpl0102_id, | |
156 | }; | |
157 | ||
158 | module_i2c_driver(tpl0102_driver); | |
159 | ||
160 | MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>"); | |
161 | MODULE_DESCRIPTION("TPL0102 digital potentiometer"); | |
162 | MODULE_LICENSE("GPL"); |