xref: /openbmc/linux/drivers/iio/light/adjd_s311.c (revision ee89bd6b)
1 /*
2  * adjd_s311.c - Support for ADJD-S311-CR999 digital color sensor
3  *
4  * Copyright (C) 2012 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  * driver for ADJD-S311-CR999 digital color sensor (10-bit channels for
11  * red, green, blue, clear); 7-bit I2C slave address 0x74
12  *
13  * limitations: no calibration, no offset mode, no sleep mode
14  */
15 
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/interrupt.h>
19 #include <linux/i2c.h>
20 #include <linux/slab.h>
21 #include <linux/delay.h>
22 #include <linux/bitmap.h>
23 #include <linux/err.h>
24 #include <linux/irq.h>
25 
26 #include <linux/iio/iio.h>
27 #include <linux/iio/sysfs.h>
28 #include <linux/iio/trigger_consumer.h>
29 #include <linux/iio/buffer.h>
30 #include <linux/iio/triggered_buffer.h>
31 
32 #define ADJD_S311_DRV_NAME "adjd_s311"
33 
34 #define ADJD_S311_CTRL		0x00
35 #define ADJD_S311_CONFIG	0x01
36 #define ADJD_S311_CAP_RED	0x06
37 #define ADJD_S311_CAP_GREEN	0x07
38 #define ADJD_S311_CAP_BLUE	0x08
39 #define ADJD_S311_CAP_CLEAR	0x09
40 #define ADJD_S311_INT_RED_LO	0x0a
41 #define ADJD_S311_INT_RED_HI	0x0b
42 #define ADJD_S311_INT_GREEN_LO	0x0c
43 #define ADJD_S311_INT_GREEN_HI	0x0d
44 #define ADJD_S311_INT_BLUE_LO	0x0e
45 #define ADJD_S311_INT_BLUE_HI	0x0f
46 #define ADJD_S311_INT_CLEAR_LO	0x10
47 #define ADJD_S311_INT_CLEAR_HI	0x11
48 #define ADJD_S311_DATA_RED_LO	0x40
49 #define ADJD_S311_DATA_RED_HI	0x41
50 #define ADJD_S311_DATA_GREEN_LO	0x42
51 #define ADJD_S311_DATA_GREEN_HI	0x43
52 #define ADJD_S311_DATA_BLUE_LO	0x44
53 #define ADJD_S311_DATA_BLUE_HI	0x45
54 #define ADJD_S311_DATA_CLEAR_LO	0x46
55 #define ADJD_S311_DATA_CLEAR_HI	0x47
56 #define ADJD_S311_OFFSET_RED	0x48
57 #define ADJD_S311_OFFSET_GREEN	0x49
58 #define ADJD_S311_OFFSET_BLUE	0x4a
59 #define ADJD_S311_OFFSET_CLEAR	0x4b
60 
61 #define ADJD_S311_CTRL_GOFS	0x02
62 #define ADJD_S311_CTRL_GSSR	0x01
63 #define ADJD_S311_CAP_MASK	0x0f
64 #define ADJD_S311_INT_MASK	0x0fff
65 #define ADJD_S311_DATA_MASK	0x03ff
66 
67 struct adjd_s311_data {
68 	struct i2c_client *client;
69 	u16 *buffer;
70 };
71 
72 enum adjd_s311_channel_idx {
73 	IDX_RED, IDX_GREEN, IDX_BLUE, IDX_CLEAR
74 };
75 
76 #define ADJD_S311_DATA_REG(chan) (ADJD_S311_DATA_RED_LO + (chan) * 2)
77 #define ADJD_S311_INT_REG(chan) (ADJD_S311_INT_RED_LO + (chan) * 2)
78 #define ADJD_S311_CAP_REG(chan) (ADJD_S311_CAP_RED + (chan))
79 
80 static int adjd_s311_req_data(struct iio_dev *indio_dev)
81 {
82 	struct adjd_s311_data *data = iio_priv(indio_dev);
83 	int tries = 10;
84 
85 	int ret = i2c_smbus_write_byte_data(data->client, ADJD_S311_CTRL,
86 		ADJD_S311_CTRL_GSSR);
87 	if (ret < 0)
88 		return ret;
89 
90 	while (tries--) {
91 		ret = i2c_smbus_read_byte_data(data->client, ADJD_S311_CTRL);
92 		if (ret < 0)
93 			return ret;
94 		if (!(ret & ADJD_S311_CTRL_GSSR))
95 			break;
96 		msleep(20);
97 	}
98 
99 	if (tries < 0) {
100 		dev_err(&data->client->dev,
101 			"adjd_s311_req_data() failed, data not ready\n");
102 		return -EIO;
103 	}
104 
105 	return 0;
106 }
107 
108 static int adjd_s311_read_data(struct iio_dev *indio_dev, u8 reg, int *val)
109 {
110 	struct adjd_s311_data *data = iio_priv(indio_dev);
111 
112 	int ret = adjd_s311_req_data(indio_dev);
113 	if (ret < 0)
114 		return ret;
115 
116 	ret = i2c_smbus_read_word_data(data->client, reg);
117 	if (ret < 0)
118 		return ret;
119 
120 	*val = ret & ADJD_S311_DATA_MASK;
121 
122 	return 0;
123 }
124 
125 static ssize_t adjd_s311_read_int_time(struct iio_dev *indio_dev,
126 	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
127 {
128 	struct adjd_s311_data *data = iio_priv(indio_dev);
129 	s32 ret;
130 
131 	ret = i2c_smbus_read_word_data(data->client,
132 		ADJD_S311_INT_REG(chan->address));
133 	if (ret < 0)
134 		return ret;
135 
136 	return sprintf(buf, "%d\n", ret & ADJD_S311_INT_MASK);
137 }
138 
139 static ssize_t adjd_s311_write_int_time(struct iio_dev *indio_dev,
140 	 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
141 	 size_t len)
142 {
143 	struct adjd_s311_data *data = iio_priv(indio_dev);
144 	unsigned long int_time;
145 	int ret;
146 
147 	ret = kstrtoul(buf, 10, &int_time);
148 	if (ret)
149 		return ret;
150 
151 	if (int_time > ADJD_S311_INT_MASK)
152 		return -EINVAL;
153 
154 	ret = i2c_smbus_write_word_data(data->client,
155 		ADJD_S311_INT_REG(chan->address), int_time);
156 	if (ret < 0)
157 		return ret;
158 
159 	return len;
160 }
161 
162 static irqreturn_t adjd_s311_trigger_handler(int irq, void *p)
163 {
164 	struct iio_poll_func *pf = p;
165 	struct iio_dev *indio_dev = pf->indio_dev;
166 	struct adjd_s311_data *data = iio_priv(indio_dev);
167 	s64 time_ns = iio_get_time_ns();
168 	int len = 0;
169 	int i, j = 0;
170 
171 	int ret = adjd_s311_req_data(indio_dev);
172 	if (ret < 0)
173 		goto done;
174 
175 	for_each_set_bit(i, indio_dev->active_scan_mask,
176 		indio_dev->masklength) {
177 		ret = i2c_smbus_read_word_data(data->client,
178 			ADJD_S311_DATA_REG(i));
179 		if (ret < 0)
180 			goto done;
181 
182 		data->buffer[j++] = ret & ADJD_S311_DATA_MASK;
183 		len += 2;
184 	}
185 
186 	if (indio_dev->scan_timestamp)
187 		*(s64 *)((u8 *)data->buffer + ALIGN(len, sizeof(s64)))
188 			= time_ns;
189 	iio_push_to_buffers(indio_dev, (u8 *)data->buffer);
190 
191 done:
192 	iio_trigger_notify_done(indio_dev->trig);
193 
194 	return IRQ_HANDLED;
195 }
196 
197 static const struct iio_chan_spec_ext_info adjd_s311_ext_info[] = {
198 	{
199 		.name = "integration_time",
200 		.read = adjd_s311_read_int_time,
201 		.write = adjd_s311_write_int_time,
202 	},
203 	{ }
204 };
205 
206 #define ADJD_S311_CHANNEL(_color, _scan_idx) { \
207 	.type = IIO_INTENSITY, \
208 	.modified = 1, \
209 	.address = (IDX_##_color), \
210 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
211 		BIT(IIO_CHAN_INFO_HARDWAREGAIN), \
212 	.channel2 = (IIO_MOD_LIGHT_##_color), \
213 	.scan_index = (_scan_idx), \
214 	.scan_type = IIO_ST('u', 10, 16, 0), \
215 	.ext_info = adjd_s311_ext_info, \
216 }
217 
218 static const struct iio_chan_spec adjd_s311_channels[] = {
219 	ADJD_S311_CHANNEL(RED, 0),
220 	ADJD_S311_CHANNEL(GREEN, 1),
221 	ADJD_S311_CHANNEL(BLUE, 2),
222 	ADJD_S311_CHANNEL(CLEAR, 3),
223 	IIO_CHAN_SOFT_TIMESTAMP(4),
224 };
225 
226 static int adjd_s311_read_raw(struct iio_dev *indio_dev,
227 			   struct iio_chan_spec const *chan,
228 			   int *val, int *val2, long mask)
229 {
230 	struct adjd_s311_data *data = iio_priv(indio_dev);
231 	int ret;
232 
233 	switch (mask) {
234 	case IIO_CHAN_INFO_RAW:
235 		ret = adjd_s311_read_data(indio_dev, chan->address, val);
236 		if (ret < 0)
237 			return ret;
238 		return IIO_VAL_INT;
239 	case IIO_CHAN_INFO_HARDWAREGAIN:
240 		ret = i2c_smbus_read_byte_data(data->client,
241 			ADJD_S311_CAP_REG(chan->address));
242 		if (ret < 0)
243 			return ret;
244 		*val = ret & ADJD_S311_CAP_MASK;
245 		return IIO_VAL_INT;
246 	}
247 	return -EINVAL;
248 }
249 
250 static int adjd_s311_write_raw(struct iio_dev *indio_dev,
251 			       struct iio_chan_spec const *chan,
252 			       int val, int val2, long mask)
253 {
254 	struct adjd_s311_data *data = iio_priv(indio_dev);
255 	int ret;
256 
257 	switch (mask) {
258 	case IIO_CHAN_INFO_HARDWAREGAIN:
259 		if (val < 0 || val > ADJD_S311_CAP_MASK)
260 			return -EINVAL;
261 
262 		ret = i2c_smbus_write_byte_data(data->client,
263 			ADJD_S311_CAP_REG(chan->address), val);
264 		return ret;
265 	}
266 	return -EINVAL;
267 }
268 
269 static int adjd_s311_update_scan_mode(struct iio_dev *indio_dev,
270 	const unsigned long *scan_mask)
271 {
272 	struct adjd_s311_data *data = iio_priv(indio_dev);
273 
274 	kfree(data->buffer);
275 	data->buffer = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
276 	if (data->buffer == NULL)
277 		return -ENOMEM;
278 
279 	return 0;
280 }
281 
282 static const struct iio_info adjd_s311_info = {
283 	.read_raw = adjd_s311_read_raw,
284 	.write_raw = adjd_s311_write_raw,
285 	.update_scan_mode = adjd_s311_update_scan_mode,
286 	.driver_module = THIS_MODULE,
287 };
288 
289 static int adjd_s311_probe(struct i2c_client *client,
290 			   const struct i2c_device_id *id)
291 {
292 	struct adjd_s311_data *data;
293 	struct iio_dev *indio_dev;
294 	int err;
295 
296 	indio_dev = iio_device_alloc(sizeof(*data));
297 	if (indio_dev == NULL) {
298 		err = -ENOMEM;
299 		goto exit;
300 	}
301 	data = iio_priv(indio_dev);
302 	i2c_set_clientdata(client, indio_dev);
303 	data->client = client;
304 
305 	indio_dev->dev.parent = &client->dev;
306 	indio_dev->info = &adjd_s311_info;
307 	indio_dev->name = ADJD_S311_DRV_NAME;
308 	indio_dev->channels = adjd_s311_channels;
309 	indio_dev->num_channels = ARRAY_SIZE(adjd_s311_channels);
310 	indio_dev->modes = INDIO_DIRECT_MODE;
311 
312 	err = iio_triggered_buffer_setup(indio_dev, NULL,
313 		adjd_s311_trigger_handler, NULL);
314 	if (err < 0)
315 		goto exit_free_device;
316 
317 	err = iio_device_register(indio_dev);
318 	if (err)
319 		goto exit_unreg_buffer;
320 
321 	dev_info(&client->dev, "ADJD-S311 color sensor registered\n");
322 
323 	return 0;
324 
325 exit_unreg_buffer:
326 	iio_triggered_buffer_cleanup(indio_dev);
327 exit_free_device:
328 	iio_device_free(indio_dev);
329 exit:
330 	return err;
331 }
332 
333 static int adjd_s311_remove(struct i2c_client *client)
334 {
335 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
336 	struct adjd_s311_data *data = iio_priv(indio_dev);
337 
338 	iio_device_unregister(indio_dev);
339 	iio_triggered_buffer_cleanup(indio_dev);
340 	kfree(data->buffer);
341 	iio_device_free(indio_dev);
342 
343 	return 0;
344 }
345 
346 static const struct i2c_device_id adjd_s311_id[] = {
347 	{ "adjd_s311", 0 },
348 	{ }
349 };
350 MODULE_DEVICE_TABLE(i2c, adjd_s311_id);
351 
352 static struct i2c_driver adjd_s311_driver = {
353 	.driver = {
354 		.name	= ADJD_S311_DRV_NAME,
355 	},
356 	.probe		= adjd_s311_probe,
357 	.remove		= adjd_s311_remove,
358 	.id_table	= adjd_s311_id,
359 };
360 module_i2c_driver(adjd_s311_driver);
361 
362 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
363 MODULE_DESCRIPTION("ADJD-S311 color sensor");
364 MODULE_LICENSE("GPL");
365