xref: /openbmc/linux/drivers/iio/light/isl29125.c (revision 2c684d89)
1 /*
2  * isl29125.c - Support for Intersil ISL29125 RGB light sensor
3  *
4  * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
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  * RGB light sensor with 16-bit channels for red, green, blue);
11  * 7-bit I2C slave address 0x44
12  *
13  * TODO: interrupt support, IR compensation, thresholds, 12bit
14  */
15 
16 #include <linux/module.h>
17 #include <linux/i2c.h>
18 #include <linux/delay.h>
19 #include <linux/pm.h>
20 
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
23 #include <linux/iio/trigger_consumer.h>
24 #include <linux/iio/buffer.h>
25 #include <linux/iio/triggered_buffer.h>
26 
27 #define ISL29125_DRV_NAME "isl29125"
28 
29 #define ISL29125_DEVICE_ID 0x00
30 #define ISL29125_CONF1 0x01
31 #define ISL29125_CONF2 0x02
32 #define ISL29125_CONF3 0x03
33 #define ISL29125_STATUS 0x08
34 #define ISL29125_GREEN_DATA 0x09
35 #define ISL29125_RED_DATA 0x0b
36 #define ISL29125_BLUE_DATA 0x0d
37 
38 #define ISL29125_ID 0x7d
39 
40 #define ISL29125_MODE_MASK GENMASK(2, 0)
41 #define ISL29125_MODE_PD 0x0
42 #define ISL29125_MODE_G 0x1
43 #define ISL29125_MODE_R 0x2
44 #define ISL29125_MODE_B 0x3
45 #define ISL29125_MODE_RGB 0x5
46 
47 #define ISL29125_MODE_RANGE BIT(3)
48 
49 #define ISL29125_STATUS_CONV BIT(1)
50 
51 struct isl29125_data {
52 	struct i2c_client *client;
53 	struct mutex lock;
54 	u8 conf1;
55 	u16 buffer[8]; /* 3x 16-bit, padding, 8 bytes timestamp */
56 };
57 
58 #define ISL29125_CHANNEL(_color, _si) { \
59 	.type = IIO_INTENSITY, \
60 	.modified = 1, \
61 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
62 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
63 	.channel2 = IIO_MOD_LIGHT_##_color, \
64 	.scan_index = _si, \
65 	.scan_type = { \
66 		.sign = 'u', \
67 		.realbits = 16, \
68 		.storagebits = 16, \
69 		.endianness = IIO_CPU, \
70 	}, \
71 }
72 
73 static const struct iio_chan_spec isl29125_channels[] = {
74 	ISL29125_CHANNEL(GREEN, 0),
75 	ISL29125_CHANNEL(RED, 1),
76 	ISL29125_CHANNEL(BLUE, 2),
77 	IIO_CHAN_SOFT_TIMESTAMP(3),
78 };
79 
80 static const struct {
81 	u8 mode, data;
82 } isl29125_regs[] = {
83 	{ISL29125_MODE_G, ISL29125_GREEN_DATA},
84 	{ISL29125_MODE_R, ISL29125_RED_DATA},
85 	{ISL29125_MODE_B, ISL29125_BLUE_DATA},
86 };
87 
88 static int isl29125_read_data(struct isl29125_data *data, int si)
89 {
90 	int tries = 5;
91 	int ret;
92 
93 	ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
94 		data->conf1 | isl29125_regs[si].mode);
95 	if (ret < 0)
96 		return ret;
97 
98 	msleep(101);
99 
100 	while (tries--) {
101 		ret = i2c_smbus_read_byte_data(data->client, ISL29125_STATUS);
102 		if (ret < 0)
103 			goto fail;
104 		if (ret & ISL29125_STATUS_CONV)
105 			break;
106 		msleep(20);
107 	}
108 
109 	if (tries < 0) {
110 		dev_err(&data->client->dev, "data not ready\n");
111 		ret = -EIO;
112 		goto fail;
113 	}
114 
115 	ret = i2c_smbus_read_word_data(data->client, isl29125_regs[si].data);
116 
117 fail:
118 	i2c_smbus_write_byte_data(data->client, ISL29125_CONF1, data->conf1);
119 	return ret;
120 }
121 
122 static int isl29125_read_raw(struct iio_dev *indio_dev,
123 			   struct iio_chan_spec const *chan,
124 			   int *val, int *val2, long mask)
125 {
126 	struct isl29125_data *data = iio_priv(indio_dev);
127 	int ret;
128 
129 	switch (mask) {
130 	case IIO_CHAN_INFO_RAW:
131 		if (iio_buffer_enabled(indio_dev))
132 			return -EBUSY;
133 		mutex_lock(&data->lock);
134 		ret = isl29125_read_data(data, chan->scan_index);
135 		mutex_unlock(&data->lock);
136 		if (ret < 0)
137 			return ret;
138 		*val = ret;
139 		return IIO_VAL_INT;
140 	case IIO_CHAN_INFO_SCALE:
141 		*val = 0;
142 		if (data->conf1 & ISL29125_MODE_RANGE)
143 			*val2 = 152590; /* 10k lux full range */
144 		else
145 			*val2 = 5722; /* 375 lux full range */
146 		return IIO_VAL_INT_PLUS_MICRO;
147 	}
148 	return -EINVAL;
149 }
150 
151 static int isl29125_write_raw(struct iio_dev *indio_dev,
152 			       struct iio_chan_spec const *chan,
153 			       int val, int val2, long mask)
154 {
155 	struct isl29125_data *data = iio_priv(indio_dev);
156 
157 	switch (mask) {
158 	case IIO_CHAN_INFO_SCALE:
159 		if (val != 0)
160 			return -EINVAL;
161 		if (val2 == 152590)
162 			data->conf1 |= ISL29125_MODE_RANGE;
163 		else if (val2 == 5722)
164 			data->conf1 &= ~ISL29125_MODE_RANGE;
165 		else
166 			return -EINVAL;
167 		return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
168 			data->conf1);
169 	default:
170 		return -EINVAL;
171 	}
172 }
173 
174 static irqreturn_t isl29125_trigger_handler(int irq, void *p)
175 {
176 	struct iio_poll_func *pf = p;
177 	struct iio_dev *indio_dev = pf->indio_dev;
178 	struct isl29125_data *data = iio_priv(indio_dev);
179 	int i, j = 0;
180 
181 	for_each_set_bit(i, indio_dev->active_scan_mask,
182 		indio_dev->masklength) {
183 		int ret = i2c_smbus_read_word_data(data->client,
184 			isl29125_regs[i].data);
185 		if (ret < 0)
186 			goto done;
187 
188 		data->buffer[j++] = ret;
189 	}
190 
191 	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
192 		iio_get_time_ns());
193 
194 done:
195 	iio_trigger_notify_done(indio_dev->trig);
196 
197 	return IRQ_HANDLED;
198 }
199 
200 static IIO_CONST_ATTR(scale_available, "0.005722 0.152590");
201 
202 static struct attribute *isl29125_attributes[] = {
203 	&iio_const_attr_scale_available.dev_attr.attr,
204 	NULL
205 };
206 
207 static const struct attribute_group isl29125_attribute_group = {
208 	.attrs = isl29125_attributes,
209 };
210 
211 static const struct iio_info isl29125_info = {
212 	.read_raw = isl29125_read_raw,
213 	.write_raw = isl29125_write_raw,
214 	.attrs = &isl29125_attribute_group,
215 	.driver_module = THIS_MODULE,
216 };
217 
218 static int isl29125_buffer_preenable(struct iio_dev *indio_dev)
219 {
220 	struct isl29125_data *data = iio_priv(indio_dev);
221 
222 	data->conf1 |= ISL29125_MODE_RGB;
223 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
224 		data->conf1);
225 }
226 
227 static int isl29125_buffer_predisable(struct iio_dev *indio_dev)
228 {
229 	struct isl29125_data *data = iio_priv(indio_dev);
230 	int ret;
231 
232 	ret = iio_triggered_buffer_predisable(indio_dev);
233 	if (ret < 0)
234 		return ret;
235 
236 	data->conf1 &= ~ISL29125_MODE_MASK;
237 	data->conf1 |= ISL29125_MODE_PD;
238 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
239 		data->conf1);
240 }
241 
242 static const struct iio_buffer_setup_ops isl29125_buffer_setup_ops = {
243 	.preenable = isl29125_buffer_preenable,
244 	.postenable = &iio_triggered_buffer_postenable,
245 	.predisable = isl29125_buffer_predisable,
246 };
247 
248 static int isl29125_probe(struct i2c_client *client,
249 			   const struct i2c_device_id *id)
250 {
251 	struct isl29125_data *data;
252 	struct iio_dev *indio_dev;
253 	int ret;
254 
255 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
256 	if (indio_dev == NULL)
257 		return -ENOMEM;
258 
259 	data = iio_priv(indio_dev);
260 	i2c_set_clientdata(client, indio_dev);
261 	data->client = client;
262 	mutex_init(&data->lock);
263 
264 	indio_dev->dev.parent = &client->dev;
265 	indio_dev->info = &isl29125_info;
266 	indio_dev->name = ISL29125_DRV_NAME;
267 	indio_dev->channels = isl29125_channels;
268 	indio_dev->num_channels = ARRAY_SIZE(isl29125_channels);
269 	indio_dev->modes = INDIO_DIRECT_MODE;
270 
271 	ret = i2c_smbus_read_byte_data(data->client, ISL29125_DEVICE_ID);
272 	if (ret < 0)
273 		return ret;
274 	if (ret != ISL29125_ID)
275 		return -ENODEV;
276 
277 	data->conf1 = ISL29125_MODE_PD | ISL29125_MODE_RANGE;
278 	ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
279 		data->conf1);
280 	if (ret < 0)
281 		return ret;
282 
283 	ret = i2c_smbus_write_byte_data(data->client, ISL29125_STATUS, 0);
284 	if (ret < 0)
285 		return ret;
286 
287 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
288 		isl29125_trigger_handler, &isl29125_buffer_setup_ops);
289 	if (ret < 0)
290 		return ret;
291 
292 	ret = iio_device_register(indio_dev);
293 	if (ret < 0)
294 		goto buffer_cleanup;
295 
296 	return 0;
297 
298 buffer_cleanup:
299 	iio_triggered_buffer_cleanup(indio_dev);
300 	return ret;
301 }
302 
303 static int isl29125_powerdown(struct isl29125_data *data)
304 {
305 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
306 		(data->conf1 & ~ISL29125_MODE_MASK) | ISL29125_MODE_PD);
307 }
308 
309 static int isl29125_remove(struct i2c_client *client)
310 {
311 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
312 
313 	iio_device_unregister(indio_dev);
314 	iio_triggered_buffer_cleanup(indio_dev);
315 	isl29125_powerdown(iio_priv(indio_dev));
316 
317 	return 0;
318 }
319 
320 #ifdef CONFIG_PM_SLEEP
321 static int isl29125_suspend(struct device *dev)
322 {
323 	struct isl29125_data *data = iio_priv(i2c_get_clientdata(
324 		to_i2c_client(dev)));
325 	return isl29125_powerdown(data);
326 }
327 
328 static int isl29125_resume(struct device *dev)
329 {
330 	struct isl29125_data *data = iio_priv(i2c_get_clientdata(
331 		to_i2c_client(dev)));
332 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
333 		data->conf1);
334 }
335 #endif
336 
337 static SIMPLE_DEV_PM_OPS(isl29125_pm_ops, isl29125_suspend, isl29125_resume);
338 
339 static const struct i2c_device_id isl29125_id[] = {
340 	{ "isl29125", 0 },
341 	{ }
342 };
343 MODULE_DEVICE_TABLE(i2c, isl29125_id);
344 
345 static struct i2c_driver isl29125_driver = {
346 	.driver = {
347 		.name	= ISL29125_DRV_NAME,
348 		.pm	= &isl29125_pm_ops,
349 	},
350 	.probe		= isl29125_probe,
351 	.remove		= isl29125_remove,
352 	.id_table	= isl29125_id,
353 };
354 module_i2c_driver(isl29125_driver);
355 
356 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
357 MODULE_DESCRIPTION("ISL29125 RGB light sensor driver");
358 MODULE_LICENSE("GPL");
359