1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * isl29125.c - Support for Intersil ISL29125 RGB light sensor
4  *
5  * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
6  *
7  * RGB light sensor with 16-bit channels for red, green, blue);
8  * 7-bit I2C slave address 0x44
9  *
10  * TODO: interrupt support, IR compensation, thresholds, 12bit
11  */
12 
13 #include <linux/module.h>
14 #include <linux/i2c.h>
15 #include <linux/delay.h>
16 #include <linux/pm.h>
17 
18 #include <linux/iio/iio.h>
19 #include <linux/iio/sysfs.h>
20 #include <linux/iio/trigger_consumer.h>
21 #include <linux/iio/buffer.h>
22 #include <linux/iio/triggered_buffer.h>
23 
24 #define ISL29125_DRV_NAME "isl29125"
25 
26 #define ISL29125_DEVICE_ID 0x00
27 #define ISL29125_CONF1 0x01
28 #define ISL29125_CONF2 0x02
29 #define ISL29125_CONF3 0x03
30 #define ISL29125_STATUS 0x08
31 #define ISL29125_GREEN_DATA 0x09
32 #define ISL29125_RED_DATA 0x0b
33 #define ISL29125_BLUE_DATA 0x0d
34 
35 #define ISL29125_ID 0x7d
36 
37 #define ISL29125_MODE_MASK GENMASK(2, 0)
38 #define ISL29125_MODE_PD 0x0
39 #define ISL29125_MODE_G 0x1
40 #define ISL29125_MODE_R 0x2
41 #define ISL29125_MODE_B 0x3
42 #define ISL29125_MODE_RGB 0x5
43 
44 #define ISL29125_SENSING_RANGE_0 5722   /* 375 lux full range */
45 #define ISL29125_SENSING_RANGE_1 152590 /* 10k lux full range */
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 	u8 conf1;
54 	/* Ensure timestamp is naturally aligned */
55 	struct {
56 		u16 chans[3];
57 		s64 timestamp __aligned(8);
58 	} scan;
59 };
60 
61 #define ISL29125_CHANNEL(_color, _si) { \
62 	.type = IIO_INTENSITY, \
63 	.modified = 1, \
64 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
65 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
66 	.channel2 = IIO_MOD_LIGHT_##_color, \
67 	.scan_index = _si, \
68 	.scan_type = { \
69 		.sign = 'u', \
70 		.realbits = 16, \
71 		.storagebits = 16, \
72 		.endianness = IIO_CPU, \
73 	}, \
74 }
75 
76 static const struct iio_chan_spec isl29125_channels[] = {
77 	ISL29125_CHANNEL(GREEN, 0),
78 	ISL29125_CHANNEL(RED, 1),
79 	ISL29125_CHANNEL(BLUE, 2),
80 	IIO_CHAN_SOFT_TIMESTAMP(3),
81 };
82 
83 static const struct {
84 	u8 mode, data;
85 } isl29125_regs[] = {
86 	{ISL29125_MODE_G, ISL29125_GREEN_DATA},
87 	{ISL29125_MODE_R, ISL29125_RED_DATA},
88 	{ISL29125_MODE_B, ISL29125_BLUE_DATA},
89 };
90 
isl29125_read_data(struct isl29125_data * data,int si)91 static int isl29125_read_data(struct isl29125_data *data, int si)
92 {
93 	int tries = 5;
94 	int ret;
95 
96 	ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
97 		data->conf1 | isl29125_regs[si].mode);
98 	if (ret < 0)
99 		return ret;
100 
101 	msleep(101);
102 
103 	while (tries--) {
104 		ret = i2c_smbus_read_byte_data(data->client, ISL29125_STATUS);
105 		if (ret < 0)
106 			goto fail;
107 		if (ret & ISL29125_STATUS_CONV)
108 			break;
109 		msleep(20);
110 	}
111 
112 	if (tries < 0) {
113 		dev_err(&data->client->dev, "data not ready\n");
114 		ret = -EIO;
115 		goto fail;
116 	}
117 
118 	ret = i2c_smbus_read_word_data(data->client, isl29125_regs[si].data);
119 
120 fail:
121 	i2c_smbus_write_byte_data(data->client, ISL29125_CONF1, data->conf1);
122 	return ret;
123 }
124 
isl29125_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)125 static int isl29125_read_raw(struct iio_dev *indio_dev,
126 			   struct iio_chan_spec const *chan,
127 			   int *val, int *val2, long mask)
128 {
129 	struct isl29125_data *data = iio_priv(indio_dev);
130 	int ret;
131 
132 	switch (mask) {
133 	case IIO_CHAN_INFO_RAW:
134 		ret = iio_device_claim_direct_mode(indio_dev);
135 		if (ret)
136 			return ret;
137 		ret = isl29125_read_data(data, chan->scan_index);
138 		iio_device_release_direct_mode(indio_dev);
139 		if (ret < 0)
140 			return ret;
141 		*val = ret;
142 		return IIO_VAL_INT;
143 	case IIO_CHAN_INFO_SCALE:
144 		*val = 0;
145 		if (data->conf1 & ISL29125_MODE_RANGE)
146 			*val2 = ISL29125_SENSING_RANGE_1; /*10k lux full range*/
147 		else
148 			*val2 = ISL29125_SENSING_RANGE_0; /*375 lux full range*/
149 		return IIO_VAL_INT_PLUS_MICRO;
150 	}
151 	return -EINVAL;
152 }
153 
isl29125_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)154 static int isl29125_write_raw(struct iio_dev *indio_dev,
155 			       struct iio_chan_spec const *chan,
156 			       int val, int val2, long mask)
157 {
158 	struct isl29125_data *data = iio_priv(indio_dev);
159 
160 	switch (mask) {
161 	case IIO_CHAN_INFO_SCALE:
162 		if (val != 0)
163 			return -EINVAL;
164 		if (val2 == ISL29125_SENSING_RANGE_1)
165 			data->conf1 |= ISL29125_MODE_RANGE;
166 		else if (val2 == ISL29125_SENSING_RANGE_0)
167 			data->conf1 &= ~ISL29125_MODE_RANGE;
168 		else
169 			return -EINVAL;
170 		return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
171 			data->conf1);
172 	default:
173 		return -EINVAL;
174 	}
175 }
176 
isl29125_trigger_handler(int irq,void * p)177 static irqreturn_t isl29125_trigger_handler(int irq, void *p)
178 {
179 	struct iio_poll_func *pf = p;
180 	struct iio_dev *indio_dev = pf->indio_dev;
181 	struct isl29125_data *data = iio_priv(indio_dev);
182 	int i, j = 0;
183 
184 	for_each_set_bit(i, indio_dev->active_scan_mask,
185 		indio_dev->masklength) {
186 		int ret = i2c_smbus_read_word_data(data->client,
187 			isl29125_regs[i].data);
188 		if (ret < 0)
189 			goto done;
190 
191 		data->scan.chans[j++] = ret;
192 	}
193 
194 	iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
195 		iio_get_time_ns(indio_dev));
196 
197 done:
198 	iio_trigger_notify_done(indio_dev->trig);
199 
200 	return IRQ_HANDLED;
201 }
202 
203 static IIO_CONST_ATTR(scale_available, "0.005722 0.152590");
204 
205 static struct attribute *isl29125_attributes[] = {
206 	&iio_const_attr_scale_available.dev_attr.attr,
207 	NULL
208 };
209 
210 static const struct attribute_group isl29125_attribute_group = {
211 	.attrs = isl29125_attributes,
212 };
213 
214 static const struct iio_info isl29125_info = {
215 	.read_raw = isl29125_read_raw,
216 	.write_raw = isl29125_write_raw,
217 	.attrs = &isl29125_attribute_group,
218 };
219 
isl29125_buffer_postenable(struct iio_dev * indio_dev)220 static int isl29125_buffer_postenable(struct iio_dev *indio_dev)
221 {
222 	struct isl29125_data *data = iio_priv(indio_dev);
223 
224 	data->conf1 |= ISL29125_MODE_RGB;
225 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
226 		data->conf1);
227 }
228 
isl29125_buffer_predisable(struct iio_dev * indio_dev)229 static int isl29125_buffer_predisable(struct iio_dev *indio_dev)
230 {
231 	struct isl29125_data *data = iio_priv(indio_dev);
232 
233 	data->conf1 &= ~ISL29125_MODE_MASK;
234 	data->conf1 |= ISL29125_MODE_PD;
235 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
236 		data->conf1);
237 }
238 
239 static const struct iio_buffer_setup_ops isl29125_buffer_setup_ops = {
240 	.postenable = isl29125_buffer_postenable,
241 	.predisable = isl29125_buffer_predisable,
242 };
243 
isl29125_probe(struct i2c_client * client,const struct i2c_device_id * id)244 static int isl29125_probe(struct i2c_client *client,
245 			   const struct i2c_device_id *id)
246 {
247 	struct isl29125_data *data;
248 	struct iio_dev *indio_dev;
249 	int ret;
250 
251 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
252 	if (indio_dev == NULL)
253 		return -ENOMEM;
254 
255 	data = iio_priv(indio_dev);
256 	i2c_set_clientdata(client, indio_dev);
257 	data->client = client;
258 
259 	indio_dev->info = &isl29125_info;
260 	indio_dev->name = ISL29125_DRV_NAME;
261 	indio_dev->channels = isl29125_channels;
262 	indio_dev->num_channels = ARRAY_SIZE(isl29125_channels);
263 	indio_dev->modes = INDIO_DIRECT_MODE;
264 
265 	ret = i2c_smbus_read_byte_data(data->client, ISL29125_DEVICE_ID);
266 	if (ret < 0)
267 		return ret;
268 	if (ret != ISL29125_ID)
269 		return -ENODEV;
270 
271 	data->conf1 = ISL29125_MODE_PD | ISL29125_MODE_RANGE;
272 	ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
273 		data->conf1);
274 	if (ret < 0)
275 		return ret;
276 
277 	ret = i2c_smbus_write_byte_data(data->client, ISL29125_STATUS, 0);
278 	if (ret < 0)
279 		return ret;
280 
281 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
282 		isl29125_trigger_handler, &isl29125_buffer_setup_ops);
283 	if (ret < 0)
284 		return ret;
285 
286 	ret = iio_device_register(indio_dev);
287 	if (ret < 0)
288 		goto buffer_cleanup;
289 
290 	return 0;
291 
292 buffer_cleanup:
293 	iio_triggered_buffer_cleanup(indio_dev);
294 	return ret;
295 }
296 
isl29125_powerdown(struct isl29125_data * data)297 static int isl29125_powerdown(struct isl29125_data *data)
298 {
299 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
300 		(data->conf1 & ~ISL29125_MODE_MASK) | ISL29125_MODE_PD);
301 }
302 
isl29125_remove(struct i2c_client * client)303 static int isl29125_remove(struct i2c_client *client)
304 {
305 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
306 
307 	iio_device_unregister(indio_dev);
308 	iio_triggered_buffer_cleanup(indio_dev);
309 	isl29125_powerdown(iio_priv(indio_dev));
310 
311 	return 0;
312 }
313 
isl29125_suspend(struct device * dev)314 static int isl29125_suspend(struct device *dev)
315 {
316 	struct isl29125_data *data = iio_priv(i2c_get_clientdata(
317 		to_i2c_client(dev)));
318 	return isl29125_powerdown(data);
319 }
320 
isl29125_resume(struct device * dev)321 static int isl29125_resume(struct device *dev)
322 {
323 	struct isl29125_data *data = iio_priv(i2c_get_clientdata(
324 		to_i2c_client(dev)));
325 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
326 		data->conf1);
327 }
328 
329 static DEFINE_SIMPLE_DEV_PM_OPS(isl29125_pm_ops, isl29125_suspend,
330 				isl29125_resume);
331 
332 static const struct i2c_device_id isl29125_id[] = {
333 	{ "isl29125", 0 },
334 	{ }
335 };
336 MODULE_DEVICE_TABLE(i2c, isl29125_id);
337 
338 static struct i2c_driver isl29125_driver = {
339 	.driver = {
340 		.name	= ISL29125_DRV_NAME,
341 		.pm	= pm_sleep_ptr(&isl29125_pm_ops),
342 	},
343 	.probe		= isl29125_probe,
344 	.remove		= isl29125_remove,
345 	.id_table	= isl29125_id,
346 };
347 module_i2c_driver(isl29125_driver);
348 
349 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
350 MODULE_DESCRIPTION("ISL29125 RGB light sensor driver");
351 MODULE_LICENSE("GPL");
352