1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * CM3323 - Capella Color Light Sensor
4 *
5 * Copyright (c) 2015, Intel Corporation.
6 *
7 * IIO driver for CM3323 (7-bit I2C slave address 0x10)
8 *
9 * TODO: calibscale to correct the lens factor
10 */
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/i2c.h>
14 #include <linux/mutex.h>
15
16 #include <linux/iio/iio.h>
17 #include <linux/iio/sysfs.h>
18
19 #define CM3323_DRV_NAME "cm3323"
20
21 #define CM3323_CMD_CONF 0x00
22 #define CM3323_CMD_RED_DATA 0x08
23 #define CM3323_CMD_GREEN_DATA 0x09
24 #define CM3323_CMD_BLUE_DATA 0x0A
25 #define CM3323_CMD_CLEAR_DATA 0x0B
26
27 #define CM3323_CONF_SD_BIT BIT(0) /* sensor disable */
28 #define CM3323_CONF_AF_BIT BIT(1) /* auto/manual force mode */
29 #define CM3323_CONF_IT_MASK GENMASK(6, 4)
30 #define CM3323_CONF_IT_SHIFT 4
31
32 #define CM3323_INT_TIME_AVAILABLE "0.04 0.08 0.16 0.32 0.64 1.28"
33
34 static const struct {
35 int val;
36 int val2;
37 } cm3323_int_time[] = {
38 {0, 40000}, /* 40 ms */
39 {0, 80000}, /* 80 ms */
40 {0, 160000}, /* 160 ms */
41 {0, 320000}, /* 320 ms */
42 {0, 640000}, /* 640 ms */
43 {1, 280000}, /* 1280 ms */
44 };
45
46 struct cm3323_data {
47 struct i2c_client *client;
48 u16 reg_conf;
49 struct mutex mutex;
50 };
51
52 #define CM3323_COLOR_CHANNEL(_color, _addr) { \
53 .type = IIO_INTENSITY, \
54 .modified = 1, \
55 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
56 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), \
57 .channel2 = IIO_MOD_LIGHT_##_color, \
58 .address = _addr, \
59 }
60
61 static const struct iio_chan_spec cm3323_channels[] = {
62 CM3323_COLOR_CHANNEL(RED, CM3323_CMD_RED_DATA),
63 CM3323_COLOR_CHANNEL(GREEN, CM3323_CMD_GREEN_DATA),
64 CM3323_COLOR_CHANNEL(BLUE, CM3323_CMD_BLUE_DATA),
65 CM3323_COLOR_CHANNEL(CLEAR, CM3323_CMD_CLEAR_DATA),
66 };
67
68 static IIO_CONST_ATTR_INT_TIME_AVAIL(CM3323_INT_TIME_AVAILABLE);
69
70 static struct attribute *cm3323_attributes[] = {
71 &iio_const_attr_integration_time_available.dev_attr.attr,
72 NULL
73 };
74
75 static const struct attribute_group cm3323_attribute_group = {
76 .attrs = cm3323_attributes,
77 };
78
cm3323_init(struct iio_dev * indio_dev)79 static int cm3323_init(struct iio_dev *indio_dev)
80 {
81 int ret;
82 struct cm3323_data *data = iio_priv(indio_dev);
83
84 ret = i2c_smbus_read_word_data(data->client, CM3323_CMD_CONF);
85 if (ret < 0) {
86 dev_err(&data->client->dev, "Error reading reg_conf\n");
87 return ret;
88 }
89
90 /* enable sensor and set auto force mode */
91 ret &= ~(CM3323_CONF_SD_BIT | CM3323_CONF_AF_BIT);
92
93 ret = i2c_smbus_write_word_data(data->client, CM3323_CMD_CONF, ret);
94 if (ret < 0) {
95 dev_err(&data->client->dev, "Error writing reg_conf\n");
96 return ret;
97 }
98
99 data->reg_conf = ret;
100
101 return 0;
102 }
103
cm3323_disable(void * data)104 static void cm3323_disable(void *data)
105 {
106 int ret;
107 struct iio_dev *indio_dev = data;
108 struct cm3323_data *cm_data = iio_priv(indio_dev);
109
110 ret = i2c_smbus_write_word_data(cm_data->client, CM3323_CMD_CONF,
111 CM3323_CONF_SD_BIT);
112 if (ret < 0)
113 dev_err(&cm_data->client->dev, "Error writing reg_conf\n");
114 }
115
cm3323_set_it_bits(struct cm3323_data * data,int val,int val2)116 static int cm3323_set_it_bits(struct cm3323_data *data, int val, int val2)
117 {
118 int i, ret;
119 u16 reg_conf;
120
121 for (i = 0; i < ARRAY_SIZE(cm3323_int_time); i++) {
122 if (val == cm3323_int_time[i].val &&
123 val2 == cm3323_int_time[i].val2) {
124 reg_conf = data->reg_conf & ~CM3323_CONF_IT_MASK;
125 reg_conf |= i << CM3323_CONF_IT_SHIFT;
126
127 ret = i2c_smbus_write_word_data(data->client,
128 CM3323_CMD_CONF,
129 reg_conf);
130 if (ret < 0)
131 return ret;
132
133 data->reg_conf = reg_conf;
134
135 return 0;
136 }
137 }
138
139 return -EINVAL;
140 }
141
cm3323_get_it_bits(struct cm3323_data * data)142 static int cm3323_get_it_bits(struct cm3323_data *data)
143 {
144 int bits;
145
146 bits = (data->reg_conf & CM3323_CONF_IT_MASK) >>
147 CM3323_CONF_IT_SHIFT;
148
149 if (bits >= ARRAY_SIZE(cm3323_int_time))
150 return -EINVAL;
151
152 return bits;
153 }
154
cm3323_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)155 static int cm3323_read_raw(struct iio_dev *indio_dev,
156 struct iio_chan_spec const *chan, int *val,
157 int *val2, long mask)
158 {
159 int ret;
160 struct cm3323_data *data = iio_priv(indio_dev);
161
162 switch (mask) {
163 case IIO_CHAN_INFO_RAW:
164 mutex_lock(&data->mutex);
165 ret = i2c_smbus_read_word_data(data->client, chan->address);
166 if (ret < 0) {
167 mutex_unlock(&data->mutex);
168 return ret;
169 }
170 *val = ret;
171 mutex_unlock(&data->mutex);
172
173 return IIO_VAL_INT;
174 case IIO_CHAN_INFO_INT_TIME:
175 mutex_lock(&data->mutex);
176 ret = cm3323_get_it_bits(data);
177 if (ret < 0) {
178 mutex_unlock(&data->mutex);
179 return ret;
180 }
181
182 *val = cm3323_int_time[ret].val;
183 *val2 = cm3323_int_time[ret].val2;
184 mutex_unlock(&data->mutex);
185
186 return IIO_VAL_INT_PLUS_MICRO;
187 default:
188 return -EINVAL;
189 }
190 }
191
cm3323_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)192 static int cm3323_write_raw(struct iio_dev *indio_dev,
193 struct iio_chan_spec const *chan, int val,
194 int val2, long mask)
195 {
196 struct cm3323_data *data = iio_priv(indio_dev);
197 int ret;
198
199 switch (mask) {
200 case IIO_CHAN_INFO_INT_TIME:
201 mutex_lock(&data->mutex);
202 ret = cm3323_set_it_bits(data, val, val2);
203 mutex_unlock(&data->mutex);
204
205 return ret;
206 default:
207 return -EINVAL;
208 }
209 }
210
211 static const struct iio_info cm3323_info = {
212 .read_raw = cm3323_read_raw,
213 .write_raw = cm3323_write_raw,
214 .attrs = &cm3323_attribute_group,
215 };
216
cm3323_probe(struct i2c_client * client)217 static int cm3323_probe(struct i2c_client *client)
218 {
219 struct cm3323_data *data;
220 struct iio_dev *indio_dev;
221 int ret;
222
223 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
224 if (!indio_dev)
225 return -ENOMEM;
226
227 data = iio_priv(indio_dev);
228 i2c_set_clientdata(client, indio_dev);
229 data->client = client;
230
231 mutex_init(&data->mutex);
232
233 indio_dev->info = &cm3323_info;
234 indio_dev->name = CM3323_DRV_NAME;
235 indio_dev->channels = cm3323_channels;
236 indio_dev->num_channels = ARRAY_SIZE(cm3323_channels);
237 indio_dev->modes = INDIO_DIRECT_MODE;
238
239 ret = cm3323_init(indio_dev);
240 if (ret < 0) {
241 dev_err(&client->dev, "cm3323 chip init failed\n");
242 return ret;
243 }
244
245 ret = devm_add_action_or_reset(&client->dev, cm3323_disable, indio_dev);
246 if (ret < 0)
247 return ret;
248
249 return devm_iio_device_register(&client->dev, indio_dev);
250 }
251
252 static const struct i2c_device_id cm3323_id[] = {
253 { "cm3323" },
254 {}
255 };
256 MODULE_DEVICE_TABLE(i2c, cm3323_id);
257
258 static const struct of_device_id cm3323_of_match[] = {
259 { .compatible = "capella,cm3323", },
260 { /* sentinel */ }
261 };
262 MODULE_DEVICE_TABLE(of, cm3323_of_match);
263
264 static struct i2c_driver cm3323_driver = {
265 .driver = {
266 .name = CM3323_DRV_NAME,
267 .of_match_table = cm3323_of_match,
268 },
269 .probe = cm3323_probe,
270 .id_table = cm3323_id,
271 };
272
273 module_i2c_driver(cm3323_driver);
274
275 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
276 MODULE_DESCRIPTION("Capella CM3323 Color Light Sensor driver");
277 MODULE_LICENSE("GPL v2");
278