Commit | Line | Data |
---|---|---|
2690be90 PM |
1 | /* |
2 | * ltr501.c - Support for Lite-On LTR501 ambient light and proximity sensor | |
3 | * | |
4 | * Copyright 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 | * 7-bit I2C slave address 0x23 | |
11 | * | |
12 | * TODO: interrupt, threshold, measurement rate, IR LED characteristics | |
13 | */ | |
14 | ||
15 | #include <linux/module.h> | |
16 | #include <linux/i2c.h> | |
17 | #include <linux/err.h> | |
18 | #include <linux/delay.h> | |
19 | ||
20 | #include <linux/iio/iio.h> | |
21 | #include <linux/iio/sysfs.h> | |
22 | #include <linux/iio/trigger_consumer.h> | |
23 | #include <linux/iio/buffer.h> | |
24 | #include <linux/iio/triggered_buffer.h> | |
25 | ||
26 | #define LTR501_DRV_NAME "ltr501" | |
27 | ||
28 | #define LTR501_ALS_CONTR 0x80 /* ALS operation mode, SW reset */ | |
29 | #define LTR501_PS_CONTR 0x81 /* PS operation mode */ | |
30 | #define LTR501_PART_ID 0x86 | |
31 | #define LTR501_MANUFAC_ID 0x87 | |
32 | #define LTR501_ALS_DATA1 0x88 /* 16-bit, little endian */ | |
33 | #define LTR501_ALS_DATA0 0x8a /* 16-bit, little endian */ | |
34 | #define LTR501_ALS_PS_STATUS 0x8c | |
35 | #define LTR501_PS_DATA 0x8d /* 16-bit, little endian */ | |
36 | ||
37 | #define LTR501_ALS_CONTR_SW_RESET BIT(2) | |
38 | #define LTR501_CONTR_PS_GAIN_MASK (BIT(3) | BIT(2)) | |
39 | #define LTR501_CONTR_PS_GAIN_SHIFT 2 | |
40 | #define LTR501_CONTR_ALS_GAIN_MASK BIT(3) | |
41 | #define LTR501_CONTR_ACTIVE BIT(1) | |
42 | ||
43 | #define LTR501_STATUS_ALS_RDY BIT(2) | |
44 | #define LTR501_STATUS_PS_RDY BIT(0) | |
45 | ||
46 | #define LTR501_PS_DATA_MASK 0x7ff | |
47 | ||
48 | struct ltr501_data { | |
49 | struct i2c_client *client; | |
50 | struct mutex lock_als, lock_ps; | |
51 | u8 als_contr, ps_contr; | |
52 | }; | |
53 | ||
54 | static int ltr501_drdy(struct ltr501_data *data, u8 drdy_mask) | |
55 | { | |
56 | int tries = 100; | |
57 | int ret; | |
58 | ||
59 | while (tries--) { | |
60 | ret = i2c_smbus_read_byte_data(data->client, | |
61 | LTR501_ALS_PS_STATUS); | |
62 | if (ret < 0) | |
63 | return ret; | |
64 | if ((ret & drdy_mask) == drdy_mask) | |
65 | return 0; | |
66 | msleep(25); | |
67 | } | |
68 | ||
69 | dev_err(&data->client->dev, "ltr501_drdy() failed, data not ready\n"); | |
70 | return -EIO; | |
71 | } | |
72 | ||
73 | static int ltr501_read_als(struct ltr501_data *data, __le16 buf[2]) | |
74 | { | |
75 | int ret = ltr501_drdy(data, LTR501_STATUS_ALS_RDY); | |
76 | if (ret < 0) | |
77 | return ret; | |
78 | /* always read both ALS channels in given order */ | |
79 | return i2c_smbus_read_i2c_block_data(data->client, | |
80 | LTR501_ALS_DATA1, 2 * sizeof(__le16), (u8 *) buf); | |
81 | } | |
82 | ||
83 | static int ltr501_read_ps(struct ltr501_data *data) | |
84 | { | |
85 | int ret = ltr501_drdy(data, LTR501_STATUS_PS_RDY); | |
86 | if (ret < 0) | |
87 | return ret; | |
88 | return i2c_smbus_read_word_data(data->client, LTR501_PS_DATA); | |
89 | } | |
90 | ||
91 | #define LTR501_INTENSITY_CHANNEL(_idx, _addr, _mod, _shared) { \ | |
92 | .type = IIO_INTENSITY, \ | |
93 | .modified = 1, \ | |
94 | .address = (_addr), \ | |
95 | .channel2 = (_mod), \ | |
96 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ | |
97 | .info_mask_shared_by_type = (_shared), \ | |
98 | .scan_index = (_idx), \ | |
99 | .scan_type = { \ | |
100 | .sign = 'u', \ | |
101 | .realbits = 16, \ | |
102 | .storagebits = 16, \ | |
103 | .endianness = IIO_CPU, \ | |
104 | } \ | |
105 | } | |
106 | ||
107 | static const struct iio_chan_spec ltr501_channels[] = { | |
108 | LTR501_INTENSITY_CHANNEL(0, LTR501_ALS_DATA0, IIO_MOD_LIGHT_BOTH, 0), | |
109 | LTR501_INTENSITY_CHANNEL(1, LTR501_ALS_DATA1, IIO_MOD_LIGHT_IR, | |
110 | BIT(IIO_CHAN_INFO_SCALE)), | |
111 | { | |
112 | .type = IIO_PROXIMITY, | |
113 | .address = LTR501_PS_DATA, | |
114 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | | |
115 | BIT(IIO_CHAN_INFO_SCALE), | |
116 | .scan_index = 2, | |
117 | .scan_type = { | |
118 | .sign = 'u', | |
119 | .realbits = 11, | |
120 | .storagebits = 16, | |
121 | .endianness = IIO_CPU, | |
122 | }, | |
123 | }, | |
124 | IIO_CHAN_SOFT_TIMESTAMP(3), | |
125 | }; | |
126 | ||
127 | static const int ltr501_ps_gain[4][2] = { | |
128 | {1, 0}, {0, 250000}, {0, 125000}, {0, 62500} | |
129 | }; | |
130 | ||
131 | static int ltr501_read_raw(struct iio_dev *indio_dev, | |
132 | struct iio_chan_spec const *chan, | |
133 | int *val, int *val2, long mask) | |
134 | { | |
135 | struct ltr501_data *data = iio_priv(indio_dev); | |
136 | __le16 buf[2]; | |
137 | int ret, i; | |
138 | ||
139 | switch (mask) { | |
140 | case IIO_CHAN_INFO_RAW: | |
141 | if (iio_buffer_enabled(indio_dev)) | |
142 | return -EBUSY; | |
143 | ||
144 | switch (chan->type) { | |
145 | case IIO_INTENSITY: | |
146 | mutex_lock(&data->lock_als); | |
147 | ret = ltr501_read_als(data, buf); | |
148 | mutex_unlock(&data->lock_als); | |
149 | if (ret < 0) | |
150 | return ret; | |
151 | *val = le16_to_cpu(chan->address == LTR501_ALS_DATA1 ? | |
152 | buf[0] : buf[1]); | |
153 | return IIO_VAL_INT; | |
154 | case IIO_PROXIMITY: | |
155 | mutex_lock(&data->lock_ps); | |
156 | ret = ltr501_read_ps(data); | |
157 | mutex_unlock(&data->lock_ps); | |
158 | if (ret < 0) | |
159 | return ret; | |
160 | *val = ret & LTR501_PS_DATA_MASK; | |
161 | return IIO_VAL_INT; | |
162 | default: | |
163 | return -EINVAL; | |
164 | } | |
165 | case IIO_CHAN_INFO_SCALE: | |
166 | switch (chan->type) { | |
167 | case IIO_INTENSITY: | |
168 | if (data->als_contr & LTR501_CONTR_ALS_GAIN_MASK) { | |
169 | *val = 0; | |
170 | *val2 = 5000; | |
171 | return IIO_VAL_INT_PLUS_MICRO; | |
172 | } else { | |
173 | *val = 1; | |
174 | *val2 = 0; | |
175 | return IIO_VAL_INT; | |
176 | } | |
177 | case IIO_PROXIMITY: | |
178 | i = (data->ps_contr & LTR501_CONTR_PS_GAIN_MASK) >> | |
179 | LTR501_CONTR_PS_GAIN_SHIFT; | |
180 | *val = ltr501_ps_gain[i][0]; | |
181 | *val2 = ltr501_ps_gain[i][1]; | |
182 | return IIO_VAL_INT_PLUS_MICRO; | |
183 | default: | |
184 | return -EINVAL; | |
185 | } | |
186 | } | |
187 | return -EINVAL; | |
188 | } | |
189 | ||
190 | static int ltr501_get_ps_gain_index(int val, int val2) | |
191 | { | |
192 | int i; | |
193 | ||
194 | for (i = 0; i < ARRAY_SIZE(ltr501_ps_gain); i++) | |
195 | if (val == ltr501_ps_gain[i][0] && val2 == ltr501_ps_gain[i][1]) | |
196 | return i; | |
197 | ||
198 | return -1; | |
199 | } | |
200 | ||
201 | static int ltr501_write_raw(struct iio_dev *indio_dev, | |
202 | struct iio_chan_spec const *chan, | |
203 | int val, int val2, long mask) | |
204 | { | |
205 | struct ltr501_data *data = iio_priv(indio_dev); | |
206 | int i; | |
207 | ||
208 | if (iio_buffer_enabled(indio_dev)) | |
209 | return -EBUSY; | |
210 | ||
211 | switch (mask) { | |
212 | case IIO_CHAN_INFO_SCALE: | |
213 | switch (chan->type) { | |
214 | case IIO_INTENSITY: | |
215 | if (val == 0 && val2 == 5000) | |
216 | data->als_contr |= LTR501_CONTR_ALS_GAIN_MASK; | |
217 | else if (val == 1 && val2 == 0) | |
218 | data->als_contr &= ~LTR501_CONTR_ALS_GAIN_MASK; | |
219 | else | |
220 | return -EINVAL; | |
221 | return i2c_smbus_write_byte_data(data->client, | |
222 | LTR501_ALS_CONTR, data->als_contr); | |
223 | case IIO_PROXIMITY: | |
224 | i = ltr501_get_ps_gain_index(val, val2); | |
225 | if (i < 0) | |
226 | return -EINVAL; | |
227 | data->ps_contr &= ~LTR501_CONTR_PS_GAIN_MASK; | |
228 | data->ps_contr |= i << LTR501_CONTR_PS_GAIN_SHIFT; | |
229 | return i2c_smbus_write_byte_data(data->client, | |
230 | LTR501_PS_CONTR, data->ps_contr); | |
231 | default: | |
232 | return -EINVAL; | |
233 | } | |
234 | } | |
235 | return -EINVAL; | |
236 | } | |
237 | ||
238 | static IIO_CONST_ATTR(in_proximity_scale_available, "1 0.25 0.125 0.0625"); | |
239 | static IIO_CONST_ATTR(in_intensity_scale_available, "1 0.005"); | |
240 | ||
241 | static struct attribute *ltr501_attributes[] = { | |
242 | &iio_const_attr_in_proximity_scale_available.dev_attr.attr, | |
243 | &iio_const_attr_in_intensity_scale_available.dev_attr.attr, | |
244 | NULL | |
245 | }; | |
246 | ||
247 | static const struct attribute_group ltr501_attribute_group = { | |
248 | .attrs = ltr501_attributes, | |
249 | }; | |
250 | ||
251 | static const struct iio_info ltr501_info = { | |
252 | .read_raw = ltr501_read_raw, | |
253 | .write_raw = ltr501_write_raw, | |
254 | .attrs = <r501_attribute_group, | |
255 | .driver_module = THIS_MODULE, | |
256 | }; | |
257 | ||
258 | static int ltr501_write_contr(struct i2c_client *client, u8 als_val, u8 ps_val) | |
259 | { | |
260 | int ret = i2c_smbus_write_byte_data(client, LTR501_ALS_CONTR, als_val); | |
261 | if (ret < 0) | |
262 | return ret; | |
263 | ||
264 | return i2c_smbus_write_byte_data(client, LTR501_PS_CONTR, ps_val); | |
265 | } | |
266 | ||
267 | static irqreturn_t ltr501_trigger_handler(int irq, void *p) | |
268 | { | |
269 | struct iio_poll_func *pf = p; | |
270 | struct iio_dev *indio_dev = pf->indio_dev; | |
271 | struct ltr501_data *data = iio_priv(indio_dev); | |
272 | u16 buf[8]; | |
273 | __le16 als_buf[2]; | |
274 | u8 mask = 0; | |
275 | int j = 0; | |
276 | int ret; | |
277 | ||
278 | memset(buf, 0, sizeof(buf)); | |
279 | ||
280 | /* figure out which data needs to be ready */ | |
281 | if (test_bit(0, indio_dev->active_scan_mask) || | |
282 | test_bit(1, indio_dev->active_scan_mask)) | |
283 | mask |= LTR501_STATUS_ALS_RDY; | |
284 | if (test_bit(2, indio_dev->active_scan_mask)) | |
285 | mask |= LTR501_STATUS_PS_RDY; | |
286 | ||
287 | ret = ltr501_drdy(data, mask); | |
288 | if (ret < 0) | |
289 | goto done; | |
290 | ||
291 | if (mask & LTR501_STATUS_ALS_RDY) { | |
292 | ret = i2c_smbus_read_i2c_block_data(data->client, | |
293 | LTR501_ALS_DATA1, sizeof(als_buf), (u8 *) als_buf); | |
294 | if (ret < 0) | |
295 | return ret; | |
296 | if (test_bit(0, indio_dev->active_scan_mask)) | |
297 | buf[j++] = le16_to_cpu(als_buf[1]); | |
298 | if (test_bit(1, indio_dev->active_scan_mask)) | |
299 | buf[j++] = le16_to_cpu(als_buf[0]); | |
300 | } | |
301 | ||
302 | if (mask & LTR501_STATUS_PS_RDY) { | |
303 | ret = i2c_smbus_read_word_data(data->client, LTR501_PS_DATA); | |
304 | if (ret < 0) | |
305 | goto done; | |
306 | buf[j++] = ret & LTR501_PS_DATA_MASK; | |
307 | } | |
308 | ||
309 | iio_push_to_buffers_with_timestamp(indio_dev, buf, | |
310 | iio_get_time_ns()); | |
311 | ||
312 | done: | |
313 | iio_trigger_notify_done(indio_dev->trig); | |
314 | ||
315 | return IRQ_HANDLED; | |
316 | } | |
317 | ||
318 | static int ltr501_init(struct ltr501_data *data) | |
319 | { | |
320 | int ret; | |
321 | ||
322 | ret = i2c_smbus_read_byte_data(data->client, LTR501_ALS_CONTR); | |
323 | if (ret < 0) | |
324 | return ret; | |
325 | data->als_contr = ret | LTR501_CONTR_ACTIVE; | |
326 | ||
327 | ret = i2c_smbus_read_byte_data(data->client, LTR501_PS_CONTR); | |
328 | if (ret < 0) | |
329 | return ret; | |
330 | data->ps_contr = ret | LTR501_CONTR_ACTIVE; | |
331 | ||
332 | return ltr501_write_contr(data->client, data->als_contr, | |
333 | data->ps_contr); | |
334 | } | |
335 | ||
1ca510b0 CO |
336 | static int ltr501_powerdown(struct ltr501_data *data) |
337 | { | |
338 | return ltr501_write_contr(data->client, | |
339 | data->als_contr & ~LTR501_CONTR_ACTIVE, | |
340 | data->ps_contr & ~LTR501_CONTR_ACTIVE); | |
341 | } | |
342 | ||
2690be90 PM |
343 | static int ltr501_probe(struct i2c_client *client, |
344 | const struct i2c_device_id *id) | |
345 | { | |
346 | struct ltr501_data *data; | |
347 | struct iio_dev *indio_dev; | |
348 | int ret; | |
349 | ||
350 | indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); | |
351 | if (!indio_dev) | |
352 | return -ENOMEM; | |
353 | ||
354 | data = iio_priv(indio_dev); | |
355 | i2c_set_clientdata(client, indio_dev); | |
356 | data->client = client; | |
357 | mutex_init(&data->lock_als); | |
358 | mutex_init(&data->lock_ps); | |
359 | ||
360 | ret = i2c_smbus_read_byte_data(data->client, LTR501_PART_ID); | |
361 | if (ret < 0) | |
362 | return ret; | |
363 | if ((ret >> 4) != 0x8) | |
364 | return -ENODEV; | |
365 | ||
366 | indio_dev->dev.parent = &client->dev; | |
367 | indio_dev->info = <r501_info; | |
368 | indio_dev->channels = ltr501_channels; | |
369 | indio_dev->num_channels = ARRAY_SIZE(ltr501_channels); | |
370 | indio_dev->name = LTR501_DRV_NAME; | |
371 | indio_dev->modes = INDIO_DIRECT_MODE; | |
372 | ||
373 | ret = ltr501_init(data); | |
374 | if (ret < 0) | |
375 | return ret; | |
376 | ||
377 | ret = iio_triggered_buffer_setup(indio_dev, NULL, | |
378 | ltr501_trigger_handler, NULL); | |
379 | if (ret) | |
1ca510b0 | 380 | goto powerdown_on_error; |
2690be90 PM |
381 | |
382 | ret = iio_device_register(indio_dev); | |
383 | if (ret) | |
384 | goto error_unreg_buffer; | |
385 | ||
386 | return 0; | |
387 | ||
388 | error_unreg_buffer: | |
389 | iio_triggered_buffer_cleanup(indio_dev); | |
1ca510b0 CO |
390 | powerdown_on_error: |
391 | ltr501_powerdown(data); | |
2690be90 PM |
392 | return ret; |
393 | } | |
394 | ||
2690be90 PM |
395 | static int ltr501_remove(struct i2c_client *client) |
396 | { | |
397 | struct iio_dev *indio_dev = i2c_get_clientdata(client); | |
398 | ||
399 | iio_device_unregister(indio_dev); | |
400 | iio_triggered_buffer_cleanup(indio_dev); | |
401 | ltr501_powerdown(iio_priv(indio_dev)); | |
402 | ||
403 | return 0; | |
404 | } | |
405 | ||
406 | #ifdef CONFIG_PM_SLEEP | |
407 | static int ltr501_suspend(struct device *dev) | |
408 | { | |
409 | struct ltr501_data *data = iio_priv(i2c_get_clientdata( | |
410 | to_i2c_client(dev))); | |
411 | return ltr501_powerdown(data); | |
412 | } | |
413 | ||
414 | static int ltr501_resume(struct device *dev) | |
415 | { | |
416 | struct ltr501_data *data = iio_priv(i2c_get_clientdata( | |
417 | to_i2c_client(dev))); | |
418 | ||
419 | return ltr501_write_contr(data->client, data->als_contr, | |
420 | data->ps_contr); | |
421 | } | |
422 | #endif | |
423 | ||
424 | static SIMPLE_DEV_PM_OPS(ltr501_pm_ops, ltr501_suspend, ltr501_resume); | |
425 | ||
426 | static const struct i2c_device_id ltr501_id[] = { | |
427 | { "ltr501", 0 }, | |
428 | { } | |
429 | }; | |
430 | MODULE_DEVICE_TABLE(i2c, ltr501_id); | |
431 | ||
432 | static struct i2c_driver ltr501_driver = { | |
433 | .driver = { | |
434 | .name = LTR501_DRV_NAME, | |
435 | .pm = <r501_pm_ops, | |
436 | .owner = THIS_MODULE, | |
437 | }, | |
438 | .probe = ltr501_probe, | |
439 | .remove = ltr501_remove, | |
440 | .id_table = ltr501_id, | |
441 | }; | |
442 | ||
443 | module_i2c_driver(ltr501_driver); | |
444 | ||
445 | MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>"); | |
446 | MODULE_DESCRIPTION("Lite-On LTR501 ambient light and proximity sensor driver"); | |
447 | MODULE_LICENSE("GPL"); |