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 		aligned_s64 timestamp;
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 
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 
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 		if (!iio_device_claim_direct(indio_dev))
135 			return -EBUSY;
136 		ret = isl29125_read_data(data, chan->scan_index);
137 		iio_device_release_direct(indio_dev);
138 		if (ret < 0)
139 			return ret;
140 		*val = ret;
141 		return IIO_VAL_INT;
142 	case IIO_CHAN_INFO_SCALE:
143 		*val = 0;
144 		if (data->conf1 & ISL29125_MODE_RANGE)
145 			*val2 = ISL29125_SENSING_RANGE_1; /*10k lux full range*/
146 		else
147 			*val2 = ISL29125_SENSING_RANGE_0; /*375 lux full range*/
148 		return IIO_VAL_INT_PLUS_MICRO;
149 	}
150 	return -EINVAL;
151 }
152 
153 static int isl29125_write_raw(struct iio_dev *indio_dev,
154 			       struct iio_chan_spec const *chan,
155 			       int val, int val2, long mask)
156 {
157 	struct isl29125_data *data = iio_priv(indio_dev);
158 
159 	switch (mask) {
160 	case IIO_CHAN_INFO_SCALE:
161 		if (val != 0)
162 			return -EINVAL;
163 		if (val2 == ISL29125_SENSING_RANGE_1)
164 			data->conf1 |= ISL29125_MODE_RANGE;
165 		else if (val2 == ISL29125_SENSING_RANGE_0)
166 			data->conf1 &= ~ISL29125_MODE_RANGE;
167 		else
168 			return -EINVAL;
169 		return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
170 			data->conf1);
171 	default:
172 		return -EINVAL;
173 	}
174 }
175 
176 static irqreturn_t isl29125_trigger_handler(int irq, void *p)
177 {
178 	struct iio_poll_func *pf = p;
179 	struct iio_dev *indio_dev = pf->indio_dev;
180 	struct isl29125_data *data = iio_priv(indio_dev);
181 	int i, j = 0;
182 
183 	iio_for_each_active_channel(indio_dev, i) {
184 		int ret = i2c_smbus_read_word_data(data->client,
185 			isl29125_regs[i].data);
186 		if (ret < 0)
187 			goto done;
188 
189 		data->scan.chans[j++] = ret;
190 	}
191 
192 	iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
193 		iio_get_time_ns(indio_dev));
194 
195 done:
196 	iio_trigger_notify_done(indio_dev->trig);
197 
198 	return IRQ_HANDLED;
199 }
200 
201 static IIO_CONST_ATTR(scale_available, "0.005722 0.152590");
202 
203 static struct attribute *isl29125_attributes[] = {
204 	&iio_const_attr_scale_available.dev_attr.attr,
205 	NULL
206 };
207 
208 static const struct attribute_group isl29125_attribute_group = {
209 	.attrs = isl29125_attributes,
210 };
211 
212 static const struct iio_info isl29125_info = {
213 	.read_raw = isl29125_read_raw,
214 	.write_raw = isl29125_write_raw,
215 	.attrs = &isl29125_attribute_group,
216 };
217 
218 static int isl29125_buffer_postenable(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 
231 	data->conf1 &= ~ISL29125_MODE_MASK;
232 	data->conf1 |= ISL29125_MODE_PD;
233 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
234 		data->conf1);
235 }
236 
237 static const struct iio_buffer_setup_ops isl29125_buffer_setup_ops = {
238 	.postenable = isl29125_buffer_postenable,
239 	.predisable = isl29125_buffer_predisable,
240 };
241 
242 static int isl29125_probe(struct i2c_client *client)
243 {
244 	struct isl29125_data *data;
245 	struct iio_dev *indio_dev;
246 	int ret;
247 
248 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
249 	if (indio_dev == NULL)
250 		return -ENOMEM;
251 
252 	data = iio_priv(indio_dev);
253 	i2c_set_clientdata(client, indio_dev);
254 	data->client = client;
255 
256 	indio_dev->info = &isl29125_info;
257 	indio_dev->name = ISL29125_DRV_NAME;
258 	indio_dev->channels = isl29125_channels;
259 	indio_dev->num_channels = ARRAY_SIZE(isl29125_channels);
260 	indio_dev->modes = INDIO_DIRECT_MODE;
261 
262 	ret = i2c_smbus_read_byte_data(data->client, ISL29125_DEVICE_ID);
263 	if (ret < 0)
264 		return ret;
265 	if (ret != ISL29125_ID)
266 		return -ENODEV;
267 
268 	data->conf1 = ISL29125_MODE_PD | ISL29125_MODE_RANGE;
269 	ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
270 		data->conf1);
271 	if (ret < 0)
272 		return ret;
273 
274 	ret = i2c_smbus_write_byte_data(data->client, ISL29125_STATUS, 0);
275 	if (ret < 0)
276 		return ret;
277 
278 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
279 		isl29125_trigger_handler, &isl29125_buffer_setup_ops);
280 	if (ret < 0)
281 		return ret;
282 
283 	ret = iio_device_register(indio_dev);
284 	if (ret < 0)
285 		goto buffer_cleanup;
286 
287 	return 0;
288 
289 buffer_cleanup:
290 	iio_triggered_buffer_cleanup(indio_dev);
291 	return ret;
292 }
293 
294 static int isl29125_powerdown(struct isl29125_data *data)
295 {
296 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
297 		(data->conf1 & ~ISL29125_MODE_MASK) | ISL29125_MODE_PD);
298 }
299 
300 static void isl29125_remove(struct i2c_client *client)
301 {
302 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
303 
304 	iio_device_unregister(indio_dev);
305 	iio_triggered_buffer_cleanup(indio_dev);
306 	isl29125_powerdown(iio_priv(indio_dev));
307 }
308 
309 static int isl29125_suspend(struct device *dev)
310 {
311 	struct isl29125_data *data = iio_priv(i2c_get_clientdata(
312 		to_i2c_client(dev)));
313 	return isl29125_powerdown(data);
314 }
315 
316 static int isl29125_resume(struct device *dev)
317 {
318 	struct isl29125_data *data = iio_priv(i2c_get_clientdata(
319 		to_i2c_client(dev)));
320 	return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
321 		data->conf1);
322 }
323 
324 static DEFINE_SIMPLE_DEV_PM_OPS(isl29125_pm_ops, isl29125_suspend,
325 				isl29125_resume);
326 
327 static const struct i2c_device_id isl29125_id[] = {
328 	{ "isl29125" },
329 	{ }
330 };
331 MODULE_DEVICE_TABLE(i2c, isl29125_id);
332 
333 static struct i2c_driver isl29125_driver = {
334 	.driver = {
335 		.name	= ISL29125_DRV_NAME,
336 		.pm	= pm_sleep_ptr(&isl29125_pm_ops),
337 	},
338 	.probe		= isl29125_probe,
339 	.remove		= isl29125_remove,
340 	.id_table	= isl29125_id,
341 };
342 module_i2c_driver(isl29125_driver);
343 
344 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
345 MODULE_DESCRIPTION("ISL29125 RGB light sensor driver");
346 MODULE_LICENSE("GPL");
347