1 /*
2 * CM3323 - Capella Color Light Sensor
3 *
4 * Copyright (c) 2015, Intel Corporation.
5 *
6 * This file is subject to the terms and conditions of version 2 of
7 * the GNU General Public License. See the file COPYING in the main
8 * directory of this archive for more details.
9 *
10 * IIO driver for CM3323 (7-bit I2C slave address 0x10)
11 *
12 * TODO: calibscale to correct the lens factor
13 */
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/i2c.h>
17 #include <linux/mutex.h>
18
19 #include <linux/iio/iio.h>
20 #include <linux/iio/sysfs.h>
21
22 #define CM3323_DRV_NAME "cm3323"
23
24 #define CM3323_CMD_CONF 0x00
25 #define CM3323_CMD_RED_DATA 0x08
26 #define CM3323_CMD_GREEN_DATA 0x09
27 #define CM3323_CMD_BLUE_DATA 0x0A
28 #define CM3323_CMD_CLEAR_DATA 0x0B
29
30 #define CM3323_CONF_SD_BIT BIT(0) /* sensor disable */
31 #define CM3323_CONF_AF_BIT BIT(1) /* auto/manual force mode */
32 #define CM3323_CONF_IT_MASK GENMASK(6, 4)
33 #define CM3323_CONF_IT_SHIFT 4
34
35 #define CM3323_INT_TIME_AVAILABLE "0.04 0.08 0.16 0.32 0.64 1.28"
36
37 static const struct {
38 int val;
39 int val2;
40 } cm3323_int_time[] = {
41 {0, 40000}, /* 40 ms */
42 {0, 80000}, /* 80 ms */
43 {0, 160000}, /* 160 ms */
44 {0, 320000}, /* 320 ms */
45 {0, 640000}, /* 640 ms */
46 {1, 280000}, /* 1280 ms */
47 };
48
49 struct cm3323_data {
50 struct i2c_client *client;
51 u16 reg_conf;
52 struct mutex mutex;
53 };
54
55 #define CM3323_COLOR_CHANNEL(_color, _addr) { \
56 .type = IIO_INTENSITY, \
57 .modified = 1, \
58 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
59 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), \
60 .channel2 = IIO_MOD_LIGHT_##_color, \
61 .address = _addr, \
62 }
63
64 static const struct iio_chan_spec cm3323_channels[] = {
65 CM3323_COLOR_CHANNEL(RED, CM3323_CMD_RED_DATA),
66 CM3323_COLOR_CHANNEL(GREEN, CM3323_CMD_GREEN_DATA),
67 CM3323_COLOR_CHANNEL(BLUE, CM3323_CMD_BLUE_DATA),
68 CM3323_COLOR_CHANNEL(CLEAR, CM3323_CMD_CLEAR_DATA),
69 };
70
71 static IIO_CONST_ATTR_INT_TIME_AVAIL(CM3323_INT_TIME_AVAILABLE);
72
73 static struct attribute *cm3323_attributes[] = {
74 &iio_const_attr_integration_time_available.dev_attr.attr,
75 NULL
76 };
77
78 static const struct attribute_group cm3323_attribute_group = {
79 .attrs = cm3323_attributes,
80 };
81
cm3323_init(struct iio_dev * indio_dev)82 static int cm3323_init(struct iio_dev *indio_dev)
83 {
84 int ret;
85 struct cm3323_data *data = iio_priv(indio_dev);
86
87 ret = i2c_smbus_read_word_data(data->client, CM3323_CMD_CONF);
88 if (ret < 0) {
89 dev_err(&data->client->dev, "Error reading reg_conf\n");
90 return ret;
91 }
92
93 /* enable sensor and set auto force mode */
94 ret &= ~(CM3323_CONF_SD_BIT | CM3323_CONF_AF_BIT);
95
96 ret = i2c_smbus_write_word_data(data->client, CM3323_CMD_CONF, ret);
97 if (ret < 0) {
98 dev_err(&data->client->dev, "Error writing reg_conf\n");
99 return ret;
100 }
101
102 data->reg_conf = ret;
103
104 return 0;
105 }
106
cm3323_disable(struct iio_dev * indio_dev)107 static void cm3323_disable(struct iio_dev *indio_dev)
108 {
109 int ret;
110 struct cm3323_data *data = iio_priv(indio_dev);
111
112 ret = i2c_smbus_write_word_data(data->client, CM3323_CMD_CONF,
113 CM3323_CONF_SD_BIT);
114 if (ret < 0)
115 dev_err(&data->client->dev, "Error writing reg_conf\n");
116 }
117
cm3323_set_it_bits(struct cm3323_data * data,int val,int val2)118 static int cm3323_set_it_bits(struct cm3323_data *data, int val, int val2)
119 {
120 int i, ret;
121 u16 reg_conf;
122
123 for (i = 0; i < ARRAY_SIZE(cm3323_int_time); i++) {
124 if (val == cm3323_int_time[i].val &&
125 val2 == cm3323_int_time[i].val2) {
126 reg_conf = data->reg_conf & ~CM3323_CONF_IT_MASK;
127 reg_conf |= i << CM3323_CONF_IT_SHIFT;
128
129 ret = i2c_smbus_write_word_data(data->client,
130 CM3323_CMD_CONF,
131 reg_conf);
132 if (ret < 0)
133 return ret;
134
135 data->reg_conf = reg_conf;
136
137 return 0;
138 }
139 }
140
141 return -EINVAL;
142 }
143
cm3323_get_it_bits(struct cm3323_data * data)144 static int cm3323_get_it_bits(struct cm3323_data *data)
145 {
146 int bits;
147
148 bits = (data->reg_conf & CM3323_CONF_IT_MASK) >>
149 CM3323_CONF_IT_SHIFT;
150
151 if (bits >= ARRAY_SIZE(cm3323_int_time))
152 return -EINVAL;
153
154 return bits;
155 }
156
cm3323_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)157 static int cm3323_read_raw(struct iio_dev *indio_dev,
158 struct iio_chan_spec const *chan, int *val,
159 int *val2, long mask)
160 {
161 int ret;
162 struct cm3323_data *data = iio_priv(indio_dev);
163
164 switch (mask) {
165 case IIO_CHAN_INFO_RAW:
166 mutex_lock(&data->mutex);
167 ret = i2c_smbus_read_word_data(data->client, chan->address);
168 if (ret < 0) {
169 mutex_unlock(&data->mutex);
170 return ret;
171 }
172 *val = ret;
173 mutex_unlock(&data->mutex);
174
175 return IIO_VAL_INT;
176 case IIO_CHAN_INFO_INT_TIME:
177 mutex_lock(&data->mutex);
178 ret = cm3323_get_it_bits(data);
179 if (ret < 0) {
180 mutex_unlock(&data->mutex);
181 return ret;
182 }
183
184 *val = cm3323_int_time[ret].val;
185 *val2 = cm3323_int_time[ret].val2;
186 mutex_unlock(&data->mutex);
187
188 return IIO_VAL_INT_PLUS_MICRO;
189 default:
190 return -EINVAL;
191 }
192 }
193
cm3323_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)194 static int cm3323_write_raw(struct iio_dev *indio_dev,
195 struct iio_chan_spec const *chan, int val,
196 int val2, long mask)
197 {
198 struct cm3323_data *data = iio_priv(indio_dev);
199 int ret;
200
201 switch (mask) {
202 case IIO_CHAN_INFO_INT_TIME:
203 mutex_lock(&data->mutex);
204 ret = cm3323_set_it_bits(data, val, val2);
205 mutex_unlock(&data->mutex);
206
207 return ret;
208 default:
209 return -EINVAL;
210 }
211 }
212
213 static const struct iio_info cm3323_info = {
214 .read_raw = cm3323_read_raw,
215 .write_raw = cm3323_write_raw,
216 .attrs = &cm3323_attribute_group,
217 };
218
cm3323_probe(struct i2c_client * client,const struct i2c_device_id * id)219 static int cm3323_probe(struct i2c_client *client,
220 const struct i2c_device_id *id)
221 {
222 struct cm3323_data *data;
223 struct iio_dev *indio_dev;
224 int ret;
225
226 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
227 if (!indio_dev)
228 return -ENOMEM;
229
230 data = iio_priv(indio_dev);
231 i2c_set_clientdata(client, indio_dev);
232 data->client = client;
233
234 mutex_init(&data->mutex);
235
236 indio_dev->dev.parent = &client->dev;
237 indio_dev->info = &cm3323_info;
238 indio_dev->name = CM3323_DRV_NAME;
239 indio_dev->channels = cm3323_channels;
240 indio_dev->num_channels = ARRAY_SIZE(cm3323_channels);
241 indio_dev->modes = INDIO_DIRECT_MODE;
242
243 ret = cm3323_init(indio_dev);
244 if (ret < 0) {
245 dev_err(&client->dev, "cm3323 chip init failed\n");
246 return ret;
247 }
248
249 ret = iio_device_register(indio_dev);
250 if (ret < 0) {
251 dev_err(&client->dev, "failed to register iio dev\n");
252 goto err_init;
253 }
254
255 return 0;
256 err_init:
257 cm3323_disable(indio_dev);
258 return ret;
259 }
260
cm3323_remove(struct i2c_client * client)261 static int cm3323_remove(struct i2c_client *client)
262 {
263 struct iio_dev *indio_dev = i2c_get_clientdata(client);
264
265 iio_device_unregister(indio_dev);
266 cm3323_disable(indio_dev);
267
268 return 0;
269 }
270
271 static const struct i2c_device_id cm3323_id[] = {
272 {"cm3323", 0},
273 {}
274 };
275 MODULE_DEVICE_TABLE(i2c, cm3323_id);
276
277 static struct i2c_driver cm3323_driver = {
278 .driver = {
279 .name = CM3323_DRV_NAME,
280 },
281 .probe = cm3323_probe,
282 .remove = cm3323_remove,
283 .id_table = cm3323_id,
284 };
285
286 module_i2c_driver(cm3323_driver);
287
288 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
289 MODULE_DESCRIPTION("Capella CM3323 Color Light Sensor driver");
290 MODULE_LICENSE("GPL v2");
291
