xref: /linux/drivers/iio/light/cm3323.c (revision 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d) 
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 
79 static int cm3323_init(struct iio_dev *indio_dev)
80 {
81 	int ret;
82 	struct cm3323_data *data = iio_priv(indio_dev);
83 	struct device *dev = &data->client->dev;
84 
85 	ret = i2c_smbus_read_word_data(data->client, CM3323_CMD_CONF);
86 	if (ret < 0)
87 		return dev_err_probe(dev, ret, "Error reading reg_conf\n");
88 
89 	/* enable sensor and set auto force mode */
90 	ret &= ~(CM3323_CONF_SD_BIT | CM3323_CONF_AF_BIT);
91 	data->reg_conf = ret;
92 
93 	ret = i2c_smbus_write_word_data(data->client, CM3323_CMD_CONF, data->reg_conf);
94 	if (ret < 0)
95 		return dev_err_probe(dev, ret, "Error writing reg_conf\n");
96 
97 	return 0;
98 }
99 
100 static void cm3323_disable(void *data)
101 {
102 	int ret;
103 	struct iio_dev *indio_dev = data;
104 	struct cm3323_data *cm_data = iio_priv(indio_dev);
105 
106 	ret = i2c_smbus_write_word_data(cm_data->client, CM3323_CMD_CONF,
107 					CM3323_CONF_SD_BIT);
108 	if (ret < 0)
109 		dev_err(&cm_data->client->dev, "Error writing reg_conf\n");
110 }
111 
112 static int cm3323_set_it_bits(struct cm3323_data *data, int val, int val2)
113 {
114 	int i, ret;
115 	u16 reg_conf;
116 
117 	for (i = 0; i < ARRAY_SIZE(cm3323_int_time); i++) {
118 		if (val == cm3323_int_time[i].val &&
119 		    val2 == cm3323_int_time[i].val2) {
120 			reg_conf = data->reg_conf & ~CM3323_CONF_IT_MASK;
121 			reg_conf |= i << CM3323_CONF_IT_SHIFT;
122 
123 			ret = i2c_smbus_write_word_data(data->client,
124 							CM3323_CMD_CONF,
125 							reg_conf);
126 			if (ret < 0)
127 				return ret;
128 
129 			data->reg_conf = reg_conf;
130 
131 			return 0;
132 		}
133 	}
134 
135 	return -EINVAL;
136 }
137 
138 static int cm3323_get_it_bits(struct cm3323_data *data)
139 {
140 	int bits;
141 
142 	bits = (data->reg_conf & CM3323_CONF_IT_MASK) >>
143 		CM3323_CONF_IT_SHIFT;
144 
145 	if (bits >= ARRAY_SIZE(cm3323_int_time))
146 		return -EINVAL;
147 
148 	return bits;
149 }
150 
151 static int cm3323_read_raw(struct iio_dev *indio_dev,
152 			   struct iio_chan_spec const *chan, int *val,
153 			   int *val2, long mask)
154 {
155 	int ret;
156 	struct cm3323_data *data = iio_priv(indio_dev);
157 
158 	switch (mask) {
159 	case IIO_CHAN_INFO_RAW:
160 		mutex_lock(&data->mutex);
161 		ret = i2c_smbus_read_word_data(data->client, chan->address);
162 		if (ret < 0) {
163 			mutex_unlock(&data->mutex);
164 			return ret;
165 		}
166 		*val = ret;
167 		mutex_unlock(&data->mutex);
168 
169 		return IIO_VAL_INT;
170 	case IIO_CHAN_INFO_INT_TIME:
171 		mutex_lock(&data->mutex);
172 		ret = cm3323_get_it_bits(data);
173 		if (ret < 0) {
174 			mutex_unlock(&data->mutex);
175 			return ret;
176 		}
177 
178 		*val = cm3323_int_time[ret].val;
179 		*val2 = cm3323_int_time[ret].val2;
180 		mutex_unlock(&data->mutex);
181 
182 		return IIO_VAL_INT_PLUS_MICRO;
183 	default:
184 		return -EINVAL;
185 	}
186 }
187 
188 static int cm3323_write_raw(struct iio_dev *indio_dev,
189 			    struct iio_chan_spec const *chan, int val,
190 			    int val2, long mask)
191 {
192 	struct cm3323_data *data = iio_priv(indio_dev);
193 	int ret;
194 
195 	switch (mask) {
196 	case IIO_CHAN_INFO_INT_TIME:
197 		mutex_lock(&data->mutex);
198 		ret = cm3323_set_it_bits(data, val, val2);
199 		mutex_unlock(&data->mutex);
200 
201 		return ret;
202 	default:
203 		return -EINVAL;
204 	}
205 }
206 
207 static const struct iio_info cm3323_info = {
208 	.read_raw	= cm3323_read_raw,
209 	.write_raw	= cm3323_write_raw,
210 	.attrs		= &cm3323_attribute_group,
211 };
212 
213 static int cm3323_probe(struct i2c_client *client)
214 {
215 	struct cm3323_data *data;
216 	struct iio_dev *indio_dev;
217 	int ret;
218 
219 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
220 	if (!indio_dev)
221 		return -ENOMEM;
222 
223 	data = iio_priv(indio_dev);
224 	i2c_set_clientdata(client, indio_dev);
225 	data->client = client;
226 
227 	mutex_init(&data->mutex);
228 
229 	indio_dev->info = &cm3323_info;
230 	indio_dev->name = CM3323_DRV_NAME;
231 	indio_dev->channels = cm3323_channels;
232 	indio_dev->num_channels = ARRAY_SIZE(cm3323_channels);
233 	indio_dev->modes = INDIO_DIRECT_MODE;
234 
235 	ret = cm3323_init(indio_dev);
236 	if (ret < 0)
237 		return ret;
238 
239 	ret = devm_add_action_or_reset(&client->dev, cm3323_disable, indio_dev);
240 	if (ret < 0)
241 		return ret;
242 
243 	return devm_iio_device_register(&client->dev, indio_dev);
244 }
245 
246 static const struct i2c_device_id cm3323_id[] = {
247 	{ .name = "cm3323" },
248 	{ }
249 };
250 MODULE_DEVICE_TABLE(i2c, cm3323_id);
251 
252 static const struct of_device_id cm3323_of_match[] = {
253 	{ .compatible = "capella,cm3323", },
254 	{ }
255 };
256 MODULE_DEVICE_TABLE(of, cm3323_of_match);
257 
258 static struct i2c_driver cm3323_driver = {
259 	.driver = {
260 		.name = CM3323_DRV_NAME,
261 		.of_match_table = cm3323_of_match,
262 	},
263 	.probe		= cm3323_probe,
264 	.id_table	= cm3323_id,
265 };
266 
267 module_i2c_driver(cm3323_driver);
268 
269 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
270 MODULE_DESCRIPTION("Capella CM3323 Color Light Sensor driver");
271 MODULE_LICENSE("GPL v2");
272