xref: /openbmc/linux/drivers/iio/light/adjd_s311.c (revision 95e9fd10)
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 	struct iio_buffer *buffer = indio_dev->buffer;
168 	s64 time_ns = iio_get_time_ns();
169 	int len = 0;
170 	int i, j = 0;
171 
172 	int ret = adjd_s311_req_data(indio_dev);
173 	if (ret < 0)
174 		goto done;
175 
176 	for_each_set_bit(i, indio_dev->active_scan_mask,
177 		indio_dev->masklength) {
178 		ret = i2c_smbus_read_word_data(data->client,
179 			ADJD_S311_DATA_REG(i));
180 		if (ret < 0)
181 			goto done;
182 
183 		data->buffer[j++] = ret & ADJD_S311_DATA_MASK;
184 		len += 2;
185 	}
186 
187 	if (indio_dev->scan_timestamp)
188 		*(s64 *)((u8 *)data->buffer + ALIGN(len, sizeof(s64)))
189 			= time_ns;
190 	iio_push_to_buffer(buffer, (u8 *)data->buffer, time_ns);
191 
192 done:
193 	iio_trigger_notify_done(indio_dev->trig);
194 
195 	return IRQ_HANDLED;
196 }
197 
198 static const struct iio_chan_spec_ext_info adjd_s311_ext_info[] = {
199 	{
200 		.name = "integration_time",
201 		.read = adjd_s311_read_int_time,
202 		.write = adjd_s311_write_int_time,
203 	},
204 	{ }
205 };
206 
207 #define ADJD_S311_CHANNEL(_color, _scan_idx) { \
208 	.type = IIO_INTENSITY, \
209 	.modified = 1, \
210 	.address = (IDX_##_color), \
211 	.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
212 		IIO_CHAN_INFO_HARDWAREGAIN_SEPARATE_BIT, \
213 	.channel2 = (IIO_MOD_LIGHT_##_color), \
214 	.scan_index = (_scan_idx), \
215 	.scan_type = IIO_ST('u', 10, 16, 0), \
216 	.ext_info = adjd_s311_ext_info, \
217 }
218 
219 static const struct iio_chan_spec adjd_s311_channels[] = {
220 	ADJD_S311_CHANNEL(RED, 0),
221 	ADJD_S311_CHANNEL(GREEN, 1),
222 	ADJD_S311_CHANNEL(BLUE, 2),
223 	ADJD_S311_CHANNEL(CLEAR, 3),
224 	IIO_CHAN_SOFT_TIMESTAMP(4),
225 };
226 
227 static int adjd_s311_read_raw(struct iio_dev *indio_dev,
228 			   struct iio_chan_spec const *chan,
229 			   int *val, int *val2, long mask)
230 {
231 	struct adjd_s311_data *data = iio_priv(indio_dev);
232 	int ret;
233 
234 	switch (mask) {
235 	case IIO_CHAN_INFO_RAW:
236 		ret = adjd_s311_read_data(indio_dev, chan->address, val);
237 		if (ret < 0)
238 			return ret;
239 		return IIO_VAL_INT;
240 	case IIO_CHAN_INFO_HARDWAREGAIN:
241 		ret = i2c_smbus_read_byte_data(data->client,
242 			ADJD_S311_CAP_REG(chan->address));
243 		if (ret < 0)
244 			return ret;
245 		*val = ret & ADJD_S311_CAP_MASK;
246 		return IIO_VAL_INT;
247 	}
248 	return -EINVAL;
249 }
250 
251 static int adjd_s311_write_raw(struct iio_dev *indio_dev,
252 			       struct iio_chan_spec const *chan,
253 			       int val, int val2, long mask)
254 {
255 	struct adjd_s311_data *data = iio_priv(indio_dev);
256 	int ret;
257 
258 	switch (mask) {
259 	case IIO_CHAN_INFO_HARDWAREGAIN:
260 		if (val < 0 || val > ADJD_S311_CAP_MASK)
261 			return -EINVAL;
262 
263 		ret = i2c_smbus_write_byte_data(data->client,
264 			ADJD_S311_CAP_REG(chan->address), val);
265 		return ret;
266 	}
267 	return -EINVAL;
268 }
269 
270 static int adjd_s311_update_scan_mode(struct iio_dev *indio_dev,
271 	const unsigned long *scan_mask)
272 {
273 	struct adjd_s311_data *data = iio_priv(indio_dev);
274 
275 	kfree(data->buffer);
276 	data->buffer = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
277 	if (data->buffer == NULL)
278 		return -ENOMEM;
279 
280 	return 0;
281 }
282 
283 static const struct iio_info adjd_s311_info = {
284 	.read_raw = adjd_s311_read_raw,
285 	.write_raw = adjd_s311_write_raw,
286 	.update_scan_mode = adjd_s311_update_scan_mode,
287 	.driver_module = THIS_MODULE,
288 };
289 
290 static int __devinit adjd_s311_probe(struct i2c_client *client,
291 			const struct i2c_device_id *id)
292 {
293 	struct adjd_s311_data *data;
294 	struct iio_dev *indio_dev;
295 	int err;
296 
297 	indio_dev = iio_device_alloc(sizeof(*data));
298 	if (indio_dev == NULL) {
299 		err = -ENOMEM;
300 		goto exit;
301 	}
302 	data = iio_priv(indio_dev);
303 	i2c_set_clientdata(client, indio_dev);
304 	data->client = client;
305 
306 	indio_dev->dev.parent = &client->dev;
307 	indio_dev->info = &adjd_s311_info;
308 	indio_dev->name = ADJD_S311_DRV_NAME;
309 	indio_dev->channels = adjd_s311_channels;
310 	indio_dev->num_channels = ARRAY_SIZE(adjd_s311_channels);
311 	indio_dev->modes = INDIO_DIRECT_MODE;
312 
313 	err = iio_triggered_buffer_setup(indio_dev, NULL,
314 		adjd_s311_trigger_handler, NULL);
315 	if (err < 0)
316 		goto exit_free_device;
317 
318 	err = iio_device_register(indio_dev);
319 	if (err)
320 		goto exit_unreg_buffer;
321 
322 	dev_info(&client->dev, "ADJD-S311 color sensor registered\n");
323 
324 	return 0;
325 
326 exit_unreg_buffer:
327 	iio_triggered_buffer_cleanup(indio_dev);
328 exit_free_device:
329 	iio_device_free(indio_dev);
330 exit:
331 	return err;
332 }
333 
334 static int __devexit adjd_s311_remove(struct i2c_client *client)
335 {
336 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
337 	struct adjd_s311_data *data = iio_priv(indio_dev);
338 
339 	iio_device_unregister(indio_dev);
340 	iio_triggered_buffer_cleanup(indio_dev);
341 	kfree(data->buffer);
342 	iio_device_free(indio_dev);
343 
344 	return 0;
345 }
346 
347 static const struct i2c_device_id adjd_s311_id[] = {
348 	{ "adjd_s311", 0 },
349 	{ }
350 };
351 MODULE_DEVICE_TABLE(i2c, adjd_s311_id);
352 
353 static struct i2c_driver adjd_s311_driver = {
354 	.driver = {
355 		.name	= ADJD_S311_DRV_NAME,
356 	},
357 	.probe		= adjd_s311_probe,
358 	.remove		= __devexit_p(adjd_s311_remove),
359 	.id_table	= adjd_s311_id,
360 };
361 module_i2c_driver(adjd_s311_driver);
362 
363 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
364 MODULE_DESCRIPTION("ADJD-S311 color sensor");
365 MODULE_LICENSE("GPL");
366