1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Device driver for monitoring ambient light intensity (lux)
4  * within the TAOS tsl258x family of devices (tsl2580, tsl2581, tsl2583).
5  *
6  * Copyright (c) 2011, TAOS Corporation.
7  * Copyright (c) 2016-2017 Brian Masney <masneyb@onstation.org>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/i2c.h>
12 #include <linux/errno.h>
13 #include <linux/delay.h>
14 #include <linux/string.h>
15 #include <linux/mutex.h>
16 #include <linux/unistd.h>
17 #include <linux/slab.h>
18 #include <linux/module.h>
19 #include <linux/iio/iio.h>
20 #include <linux/iio/sysfs.h>
21 #include <linux/pm_runtime.h>
22 
23 /* Device Registers and Masks */
24 #define TSL2583_CNTRL			0x00
25 #define TSL2583_ALS_TIME		0X01
26 #define TSL2583_INTERRUPT		0x02
27 #define TSL2583_GAIN			0x07
28 #define TSL2583_REVID			0x11
29 #define TSL2583_CHIPID			0x12
30 #define TSL2583_ALS_CHAN0LO		0x14
31 #define TSL2583_ALS_CHAN0HI		0x15
32 #define TSL2583_ALS_CHAN1LO		0x16
33 #define TSL2583_ALS_CHAN1HI		0x17
34 #define TSL2583_TMR_LO			0x18
35 #define TSL2583_TMR_HI			0x19
36 
37 /* tsl2583 cmd reg masks */
38 #define TSL2583_CMD_REG			0x80
39 #define TSL2583_CMD_SPL_FN		0x60
40 #define TSL2583_CMD_ALS_INT_CLR		0x01
41 
42 /* tsl2583 cntrl reg masks */
43 #define TSL2583_CNTL_ADC_ENBL		0x02
44 #define TSL2583_CNTL_PWR_OFF		0x00
45 #define TSL2583_CNTL_PWR_ON		0x01
46 
47 /* tsl2583 status reg masks */
48 #define TSL2583_STA_ADC_VALID		0x01
49 #define TSL2583_STA_ADC_INTR		0x10
50 
51 /* Lux calculation constants */
52 #define TSL2583_LUX_CALC_OVER_FLOW	65535
53 
54 #define TSL2583_INTERRUPT_DISABLED	0x00
55 
56 #define TSL2583_CHIP_ID			0x90
57 #define TSL2583_CHIP_ID_MASK		0xf0
58 
59 #define TSL2583_POWER_OFF_DELAY_MS	2000
60 
61 /* Per-device data */
62 struct tsl2583_als_info {
63 	u16 als_ch0;
64 	u16 als_ch1;
65 	u16 lux;
66 };
67 
68 struct tsl2583_lux {
69 	unsigned int ratio;
70 	unsigned int ch0;
71 	unsigned int ch1;
72 };
73 
74 static const struct tsl2583_lux tsl2583_default_lux[] = {
75 	{  9830,  8520, 15729 },
76 	{ 12452, 10807, 23344 },
77 	{ 14746,  6383, 11705 },
78 	{ 17695,  4063,  6554 },
79 	{     0,     0,     0 }  /* Termination segment */
80 };
81 
82 #define TSL2583_MAX_LUX_TABLE_ENTRIES 11
83 
84 struct tsl2583_settings {
85 	int als_time;
86 	int als_gain;
87 	int als_gain_trim;
88 	int als_cal_target;
89 
90 	/*
91 	 * This structure is intentionally large to accommodate updates via
92 	 * sysfs. Sized to 11 = max 10 segments + 1 termination segment.
93 	 * Assumption is that one and only one type of glass used.
94 	 */
95 	struct tsl2583_lux als_device_lux[TSL2583_MAX_LUX_TABLE_ENTRIES];
96 };
97 
98 struct tsl2583_chip {
99 	struct mutex als_mutex;
100 	struct i2c_client *client;
101 	struct tsl2583_als_info als_cur_info;
102 	struct tsl2583_settings als_settings;
103 	int als_time_scale;
104 	int als_saturation;
105 };
106 
107 struct gainadj {
108 	s16 ch0;
109 	s16 ch1;
110 	s16 mean;
111 };
112 
113 /* Index = (0 - 3) Used to validate the gain selection index */
114 static const struct gainadj gainadj[] = {
115 	{ 1, 1, 1 },
116 	{ 8, 8, 8 },
117 	{ 16, 16, 16 },
118 	{ 107, 115, 111 }
119 };
120 
121 /*
122  * Provides initial operational parameter defaults.
123  * These defaults may be changed through the device's sysfs files.
124  */
tsl2583_defaults(struct tsl2583_chip * chip)125 static void tsl2583_defaults(struct tsl2583_chip *chip)
126 {
127 	/*
128 	 * The integration time must be a multiple of 50ms and within the
129 	 * range [50, 600] ms.
130 	 */
131 	chip->als_settings.als_time = 100;
132 
133 	/*
134 	 * This is an index into the gainadj table. Assume clear glass as the
135 	 * default.
136 	 */
137 	chip->als_settings.als_gain = 0;
138 
139 	/* Default gain trim to account for aperture effects */
140 	chip->als_settings.als_gain_trim = 1000;
141 
142 	/* Known external ALS reading used for calibration */
143 	chip->als_settings.als_cal_target = 130;
144 
145 	/* Default lux table. */
146 	memcpy(chip->als_settings.als_device_lux, tsl2583_default_lux,
147 	       sizeof(tsl2583_default_lux));
148 }
149 
150 /*
151  * Reads and calculates current lux value.
152  * The raw ch0 and ch1 values of the ambient light sensed in the last
153  * integration cycle are read from the device.
154  * Time scale factor array values are adjusted based on the integration time.
155  * The raw values are multiplied by a scale factor, and device gain is obtained
156  * using gain index. Limit checks are done next, then the ratio of a multiple
157  * of ch1 value, to the ch0 value, is calculated. The array als_device_lux[]
158  * declared above is then scanned to find the first ratio value that is just
159  * above the ratio we just calculated. The ch0 and ch1 multiplier constants in
160  * the array are then used along with the time scale factor array values, to
161  * calculate the lux.
162  */
tsl2583_get_lux(struct iio_dev * indio_dev)163 static int tsl2583_get_lux(struct iio_dev *indio_dev)
164 {
165 	u16 ch0, ch1; /* separated ch0/ch1 data from device */
166 	u32 lux; /* raw lux calculated from device data */
167 	u64 lux64;
168 	u32 ratio;
169 	u8 buf[5];
170 	struct tsl2583_lux *p;
171 	struct tsl2583_chip *chip = iio_priv(indio_dev);
172 	int i, ret;
173 
174 	ret = i2c_smbus_read_byte_data(chip->client, TSL2583_CMD_REG);
175 	if (ret < 0) {
176 		dev_err(&chip->client->dev, "%s: failed to read CMD_REG register\n",
177 			__func__);
178 		goto done;
179 	}
180 
181 	/* is data new & valid */
182 	if (!(ret & TSL2583_STA_ADC_INTR)) {
183 		dev_err(&chip->client->dev, "%s: data not valid; returning last value\n",
184 			__func__);
185 		ret = chip->als_cur_info.lux; /* return LAST VALUE */
186 		goto done;
187 	}
188 
189 	for (i = 0; i < 4; i++) {
190 		int reg = TSL2583_CMD_REG | (TSL2583_ALS_CHAN0LO + i);
191 
192 		ret = i2c_smbus_read_byte_data(chip->client, reg);
193 		if (ret < 0) {
194 			dev_err(&chip->client->dev, "%s: failed to read register %x\n",
195 				__func__, reg);
196 			goto done;
197 		}
198 		buf[i] = ret;
199 	}
200 
201 	/*
202 	 * Clear the pending interrupt status bit on the chip to allow the next
203 	 * integration cycle to start. This has to be done even though this
204 	 * driver currently does not support interrupts.
205 	 */
206 	ret = i2c_smbus_write_byte(chip->client,
207 				   (TSL2583_CMD_REG | TSL2583_CMD_SPL_FN |
208 				    TSL2583_CMD_ALS_INT_CLR));
209 	if (ret < 0) {
210 		dev_err(&chip->client->dev, "%s: failed to clear the interrupt bit\n",
211 			__func__);
212 		goto done; /* have no data, so return failure */
213 	}
214 
215 	/* extract ALS/lux data */
216 	ch0 = le16_to_cpup((const __le16 *)&buf[0]);
217 	ch1 = le16_to_cpup((const __le16 *)&buf[2]);
218 
219 	chip->als_cur_info.als_ch0 = ch0;
220 	chip->als_cur_info.als_ch1 = ch1;
221 
222 	if ((ch0 >= chip->als_saturation) || (ch1 >= chip->als_saturation))
223 		goto return_max;
224 
225 	if (!ch0) {
226 		/*
227 		 * The sensor appears to be in total darkness so set the
228 		 * calculated lux to 0 and return early to avoid a division by
229 		 * zero below when calculating the ratio.
230 		 */
231 		ret = 0;
232 		chip->als_cur_info.lux = 0;
233 		goto done;
234 	}
235 
236 	/* calculate ratio */
237 	ratio = (ch1 << 15) / ch0;
238 
239 	/* convert to unscaled lux using the pointer to the table */
240 	for (p = (struct tsl2583_lux *)chip->als_settings.als_device_lux;
241 	     p->ratio != 0 && p->ratio < ratio; p++)
242 		;
243 
244 	if (p->ratio == 0) {
245 		lux = 0;
246 	} else {
247 		u32 ch0lux, ch1lux;
248 
249 		ch0lux = ((ch0 * p->ch0) +
250 			  (gainadj[chip->als_settings.als_gain].ch0 >> 1))
251 			 / gainadj[chip->als_settings.als_gain].ch0;
252 		ch1lux = ((ch1 * p->ch1) +
253 			  (gainadj[chip->als_settings.als_gain].ch1 >> 1))
254 			 / gainadj[chip->als_settings.als_gain].ch1;
255 
256 		/* note: lux is 31 bit max at this point */
257 		if (ch1lux > ch0lux) {
258 			dev_dbg(&chip->client->dev, "%s: No Data - Returning 0\n",
259 				__func__);
260 			ret = 0;
261 			chip->als_cur_info.lux = 0;
262 			goto done;
263 		}
264 
265 		lux = ch0lux - ch1lux;
266 	}
267 
268 	/* adjust for active time scale */
269 	if (chip->als_time_scale == 0)
270 		lux = 0;
271 	else
272 		lux = (lux + (chip->als_time_scale >> 1)) /
273 			chip->als_time_scale;
274 
275 	/*
276 	 * Adjust for active gain scale.
277 	 * The tsl2583_default_lux tables above have a factor of 8192 built in,
278 	 * so we need to shift right.
279 	 * User-specified gain provides a multiplier.
280 	 * Apply user-specified gain before shifting right to retain precision.
281 	 * Use 64 bits to avoid overflow on multiplication.
282 	 * Then go back to 32 bits before division to avoid using div_u64().
283 	 */
284 	lux64 = lux;
285 	lux64 = lux64 * chip->als_settings.als_gain_trim;
286 	lux64 >>= 13;
287 	lux = lux64;
288 	lux = DIV_ROUND_CLOSEST(lux, 1000);
289 
290 	if (lux > TSL2583_LUX_CALC_OVER_FLOW) { /* check for overflow */
291 return_max:
292 		lux = TSL2583_LUX_CALC_OVER_FLOW;
293 	}
294 
295 	/* Update the structure with the latest VALID lux. */
296 	chip->als_cur_info.lux = lux;
297 	ret = lux;
298 
299 done:
300 	return ret;
301 }
302 
303 /*
304  * Obtain single reading and calculate the als_gain_trim (later used
305  * to derive actual lux).
306  * Return updated gain_trim value.
307  */
tsl2583_als_calibrate(struct iio_dev * indio_dev)308 static int tsl2583_als_calibrate(struct iio_dev *indio_dev)
309 {
310 	struct tsl2583_chip *chip = iio_priv(indio_dev);
311 	unsigned int gain_trim_val;
312 	int ret;
313 	int lux_val;
314 
315 	ret = i2c_smbus_read_byte_data(chip->client,
316 				       TSL2583_CMD_REG | TSL2583_CNTRL);
317 	if (ret < 0) {
318 		dev_err(&chip->client->dev,
319 			"%s: failed to read from the CNTRL register\n",
320 			__func__);
321 		return ret;
322 	}
323 
324 	if ((ret & (TSL2583_CNTL_ADC_ENBL | TSL2583_CNTL_PWR_ON))
325 			!= (TSL2583_CNTL_ADC_ENBL | TSL2583_CNTL_PWR_ON)) {
326 		dev_err(&chip->client->dev,
327 			"%s: Device is not powered on and/or ADC is not enabled\n",
328 			__func__);
329 		return -EINVAL;
330 	} else if ((ret & TSL2583_STA_ADC_VALID) != TSL2583_STA_ADC_VALID) {
331 		dev_err(&chip->client->dev,
332 			"%s: The two ADC channels have not completed an integration cycle\n",
333 			__func__);
334 		return -ENODATA;
335 	}
336 
337 	lux_val = tsl2583_get_lux(indio_dev);
338 	if (lux_val < 0) {
339 		dev_err(&chip->client->dev, "%s: failed to get lux\n",
340 			__func__);
341 		return lux_val;
342 	}
343 
344 	/* Avoid division by zero of lux_value later on */
345 	if (lux_val == 0) {
346 		dev_err(&chip->client->dev,
347 			"%s: lux_val of 0 will produce out of range trim_value\n",
348 			__func__);
349 		return -ENODATA;
350 	}
351 
352 	gain_trim_val = (unsigned int)(((chip->als_settings.als_cal_target)
353 			* chip->als_settings.als_gain_trim) / lux_val);
354 	if ((gain_trim_val < 250) || (gain_trim_val > 4000)) {
355 		dev_err(&chip->client->dev,
356 			"%s: trim_val of %d is not within the range [250, 4000]\n",
357 			__func__, gain_trim_val);
358 		return -ENODATA;
359 	}
360 
361 	chip->als_settings.als_gain_trim = (int)gain_trim_val;
362 
363 	return 0;
364 }
365 
tsl2583_set_als_time(struct tsl2583_chip * chip)366 static int tsl2583_set_als_time(struct tsl2583_chip *chip)
367 {
368 	int als_count, als_time, ret;
369 	u8 val;
370 
371 	/* determine als integration register */
372 	als_count = DIV_ROUND_CLOSEST(chip->als_settings.als_time * 100, 270);
373 	if (!als_count)
374 		als_count = 1; /* ensure at least one cycle */
375 
376 	/* convert back to time (encompasses overrides) */
377 	als_time = DIV_ROUND_CLOSEST(als_count * 27, 10);
378 
379 	val = 256 - als_count;
380 	ret = i2c_smbus_write_byte_data(chip->client,
381 					TSL2583_CMD_REG | TSL2583_ALS_TIME,
382 					val);
383 	if (ret < 0) {
384 		dev_err(&chip->client->dev, "%s: failed to set the als time to %d\n",
385 			__func__, val);
386 		return ret;
387 	}
388 
389 	/* set chip struct re scaling and saturation */
390 	chip->als_saturation = als_count * 922; /* 90% of full scale */
391 	chip->als_time_scale = DIV_ROUND_CLOSEST(als_time, 50);
392 
393 	return ret;
394 }
395 
tsl2583_set_als_gain(struct tsl2583_chip * chip)396 static int tsl2583_set_als_gain(struct tsl2583_chip *chip)
397 {
398 	int ret;
399 
400 	/* Set the gain based on als_settings struct */
401 	ret = i2c_smbus_write_byte_data(chip->client,
402 					TSL2583_CMD_REG | TSL2583_GAIN,
403 					chip->als_settings.als_gain);
404 	if (ret < 0)
405 		dev_err(&chip->client->dev,
406 			"%s: failed to set the gain to %d\n", __func__,
407 			chip->als_settings.als_gain);
408 
409 	return ret;
410 }
411 
tsl2583_set_power_state(struct tsl2583_chip * chip,u8 state)412 static int tsl2583_set_power_state(struct tsl2583_chip *chip, u8 state)
413 {
414 	int ret;
415 
416 	ret = i2c_smbus_write_byte_data(chip->client,
417 					TSL2583_CMD_REG | TSL2583_CNTRL, state);
418 	if (ret < 0)
419 		dev_err(&chip->client->dev,
420 			"%s: failed to set the power state to %d\n", __func__,
421 			state);
422 
423 	return ret;
424 }
425 
426 /*
427  * Turn the device on.
428  * Configuration must be set before calling this function.
429  */
tsl2583_chip_init_and_power_on(struct iio_dev * indio_dev)430 static int tsl2583_chip_init_and_power_on(struct iio_dev *indio_dev)
431 {
432 	struct tsl2583_chip *chip = iio_priv(indio_dev);
433 	int ret;
434 
435 	/* Power on the device; ADC off. */
436 	ret = tsl2583_set_power_state(chip, TSL2583_CNTL_PWR_ON);
437 	if (ret < 0)
438 		return ret;
439 
440 	ret = i2c_smbus_write_byte_data(chip->client,
441 					TSL2583_CMD_REG | TSL2583_INTERRUPT,
442 					TSL2583_INTERRUPT_DISABLED);
443 	if (ret < 0) {
444 		dev_err(&chip->client->dev,
445 			"%s: failed to disable interrupts\n", __func__);
446 		return ret;
447 	}
448 
449 	ret = tsl2583_set_als_time(chip);
450 	if (ret < 0)
451 		return ret;
452 
453 	ret = tsl2583_set_als_gain(chip);
454 	if (ret < 0)
455 		return ret;
456 
457 	usleep_range(3000, 3500);
458 
459 	ret = tsl2583_set_power_state(chip, TSL2583_CNTL_PWR_ON |
460 					    TSL2583_CNTL_ADC_ENBL);
461 	if (ret < 0)
462 		return ret;
463 
464 	return ret;
465 }
466 
467 /* Sysfs Interface Functions */
468 
in_illuminance_input_target_show(struct device * dev,struct device_attribute * attr,char * buf)469 static ssize_t in_illuminance_input_target_show(struct device *dev,
470 						struct device_attribute *attr,
471 						char *buf)
472 {
473 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
474 	struct tsl2583_chip *chip = iio_priv(indio_dev);
475 	int ret;
476 
477 	mutex_lock(&chip->als_mutex);
478 	ret = sprintf(buf, "%d\n", chip->als_settings.als_cal_target);
479 	mutex_unlock(&chip->als_mutex);
480 
481 	return ret;
482 }
483 
in_illuminance_input_target_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)484 static ssize_t in_illuminance_input_target_store(struct device *dev,
485 						 struct device_attribute *attr,
486 						 const char *buf, size_t len)
487 {
488 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
489 	struct tsl2583_chip *chip = iio_priv(indio_dev);
490 	int value;
491 
492 	if (kstrtoint(buf, 0, &value) || !value)
493 		return -EINVAL;
494 
495 	mutex_lock(&chip->als_mutex);
496 	chip->als_settings.als_cal_target = value;
497 	mutex_unlock(&chip->als_mutex);
498 
499 	return len;
500 }
501 
in_illuminance_calibrate_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)502 static ssize_t in_illuminance_calibrate_store(struct device *dev,
503 					      struct device_attribute *attr,
504 					      const char *buf, size_t len)
505 {
506 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
507 	struct tsl2583_chip *chip = iio_priv(indio_dev);
508 	int value, ret;
509 
510 	if (kstrtoint(buf, 0, &value) || value != 1)
511 		return -EINVAL;
512 
513 	mutex_lock(&chip->als_mutex);
514 
515 	ret = tsl2583_als_calibrate(indio_dev);
516 	if (ret < 0)
517 		goto done;
518 
519 	ret = len;
520 done:
521 	mutex_unlock(&chip->als_mutex);
522 
523 	return ret;
524 }
525 
in_illuminance_lux_table_show(struct device * dev,struct device_attribute * attr,char * buf)526 static ssize_t in_illuminance_lux_table_show(struct device *dev,
527 					     struct device_attribute *attr,
528 					     char *buf)
529 {
530 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
531 	struct tsl2583_chip *chip = iio_priv(indio_dev);
532 	unsigned int i;
533 	int offset = 0;
534 
535 	for (i = 0; i < ARRAY_SIZE(chip->als_settings.als_device_lux); i++) {
536 		offset += sprintf(buf + offset, "%u,%u,%u,",
537 				  chip->als_settings.als_device_lux[i].ratio,
538 				  chip->als_settings.als_device_lux[i].ch0,
539 				  chip->als_settings.als_device_lux[i].ch1);
540 		if (chip->als_settings.als_device_lux[i].ratio == 0) {
541 			/*
542 			 * We just printed the first "0" entry.
543 			 * Now get rid of the extra "," and break.
544 			 */
545 			offset--;
546 			break;
547 		}
548 	}
549 
550 	offset += sprintf(buf + offset, "\n");
551 
552 	return offset;
553 }
554 
in_illuminance_lux_table_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)555 static ssize_t in_illuminance_lux_table_store(struct device *dev,
556 					      struct device_attribute *attr,
557 					      const char *buf, size_t len)
558 {
559 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
560 	struct tsl2583_chip *chip = iio_priv(indio_dev);
561 	const unsigned int max_ints = TSL2583_MAX_LUX_TABLE_ENTRIES * 3;
562 	int value[TSL2583_MAX_LUX_TABLE_ENTRIES * 3 + 1];
563 	int ret = -EINVAL;
564 	unsigned int n;
565 
566 	mutex_lock(&chip->als_mutex);
567 
568 	get_options(buf, ARRAY_SIZE(value), value);
569 
570 	/*
571 	 * We now have an array of ints starting at value[1], and
572 	 * enumerated by value[0].
573 	 * We expect each group of three ints is one table entry,
574 	 * and the last table entry is all 0.
575 	 */
576 	n = value[0];
577 	if ((n % 3) || n < 6 || n > max_ints) {
578 		dev_err(dev,
579 			"%s: The number of entries in the lux table must be a multiple of 3 and within the range [6, %d]\n",
580 			__func__, max_ints);
581 		goto done;
582 	}
583 	if ((value[n - 2] | value[n - 1] | value[n]) != 0) {
584 		dev_err(dev, "%s: The last 3 entries in the lux table must be zeros.\n",
585 			__func__);
586 		goto done;
587 	}
588 
589 	memcpy(chip->als_settings.als_device_lux, &value[1],
590 	       value[0] * sizeof(value[1]));
591 
592 	ret = len;
593 
594 done:
595 	mutex_unlock(&chip->als_mutex);
596 
597 	return ret;
598 }
599 
600 static IIO_CONST_ATTR(in_illuminance_calibscale_available, "1 8 16 111");
601 static IIO_CONST_ATTR(in_illuminance_integration_time_available,
602 		      "0.050 0.100 0.150 0.200 0.250 0.300 0.350 0.400 0.450 0.500 0.550 0.600 0.650");
603 static IIO_DEVICE_ATTR_RW(in_illuminance_input_target, 0);
604 static IIO_DEVICE_ATTR_WO(in_illuminance_calibrate, 0);
605 static IIO_DEVICE_ATTR_RW(in_illuminance_lux_table, 0);
606 
607 static struct attribute *sysfs_attrs_ctrl[] = {
608 	&iio_const_attr_in_illuminance_calibscale_available.dev_attr.attr,
609 	&iio_const_attr_in_illuminance_integration_time_available.dev_attr.attr,
610 	&iio_dev_attr_in_illuminance_input_target.dev_attr.attr,
611 	&iio_dev_attr_in_illuminance_calibrate.dev_attr.attr,
612 	&iio_dev_attr_in_illuminance_lux_table.dev_attr.attr,
613 	NULL
614 };
615 
616 static const struct attribute_group tsl2583_attribute_group = {
617 	.attrs = sysfs_attrs_ctrl,
618 };
619 
620 static const struct iio_chan_spec tsl2583_channels[] = {
621 	{
622 		.type = IIO_LIGHT,
623 		.modified = 1,
624 		.channel2 = IIO_MOD_LIGHT_IR,
625 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
626 	},
627 	{
628 		.type = IIO_LIGHT,
629 		.modified = 1,
630 		.channel2 = IIO_MOD_LIGHT_BOTH,
631 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
632 	},
633 	{
634 		.type = IIO_LIGHT,
635 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
636 				      BIT(IIO_CHAN_INFO_CALIBBIAS) |
637 				      BIT(IIO_CHAN_INFO_CALIBSCALE) |
638 				      BIT(IIO_CHAN_INFO_INT_TIME),
639 	},
640 };
641 
tsl2583_set_pm_runtime_busy(struct tsl2583_chip * chip,bool on)642 static int tsl2583_set_pm_runtime_busy(struct tsl2583_chip *chip, bool on)
643 {
644 	int ret;
645 
646 	if (on) {
647 		ret = pm_runtime_resume_and_get(&chip->client->dev);
648 	} else {
649 		pm_runtime_mark_last_busy(&chip->client->dev);
650 		ret = pm_runtime_put_autosuspend(&chip->client->dev);
651 	}
652 
653 	return ret;
654 }
655 
tsl2583_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)656 static int tsl2583_read_raw(struct iio_dev *indio_dev,
657 			    struct iio_chan_spec const *chan,
658 			    int *val, int *val2, long mask)
659 {
660 	struct tsl2583_chip *chip = iio_priv(indio_dev);
661 	int ret, pm_ret;
662 
663 	ret = tsl2583_set_pm_runtime_busy(chip, true);
664 	if (ret < 0)
665 		return ret;
666 
667 	mutex_lock(&chip->als_mutex);
668 
669 	ret = -EINVAL;
670 	switch (mask) {
671 	case IIO_CHAN_INFO_RAW:
672 		if (chan->type == IIO_LIGHT) {
673 			ret = tsl2583_get_lux(indio_dev);
674 			if (ret < 0)
675 				goto read_done;
676 
677 			/*
678 			 * From page 20 of the TSL2581, TSL2583 data
679 			 * sheet (TAOS134 − MARCH 2011):
680 			 *
681 			 * One of the photodiodes (channel 0) is
682 			 * sensitive to both visible and infrared light,
683 			 * while the second photodiode (channel 1) is
684 			 * sensitive primarily to infrared light.
685 			 */
686 			if (chan->channel2 == IIO_MOD_LIGHT_BOTH)
687 				*val = chip->als_cur_info.als_ch0;
688 			else
689 				*val = chip->als_cur_info.als_ch1;
690 
691 			ret = IIO_VAL_INT;
692 		}
693 		break;
694 	case IIO_CHAN_INFO_PROCESSED:
695 		if (chan->type == IIO_LIGHT) {
696 			ret = tsl2583_get_lux(indio_dev);
697 			if (ret < 0)
698 				goto read_done;
699 
700 			*val = ret;
701 			ret = IIO_VAL_INT;
702 		}
703 		break;
704 	case IIO_CHAN_INFO_CALIBBIAS:
705 		if (chan->type == IIO_LIGHT) {
706 			*val = chip->als_settings.als_gain_trim;
707 			ret = IIO_VAL_INT;
708 		}
709 		break;
710 	case IIO_CHAN_INFO_CALIBSCALE:
711 		if (chan->type == IIO_LIGHT) {
712 			*val = gainadj[chip->als_settings.als_gain].mean;
713 			ret = IIO_VAL_INT;
714 		}
715 		break;
716 	case IIO_CHAN_INFO_INT_TIME:
717 		if (chan->type == IIO_LIGHT) {
718 			*val = 0;
719 			*val2 = chip->als_settings.als_time;
720 			ret = IIO_VAL_INT_PLUS_MICRO;
721 		}
722 		break;
723 	default:
724 		break;
725 	}
726 
727 read_done:
728 	mutex_unlock(&chip->als_mutex);
729 
730 	if (ret < 0) {
731 		tsl2583_set_pm_runtime_busy(chip, false);
732 		return ret;
733 	}
734 
735 	/*
736 	 * Preserve the ret variable if the call to
737 	 * tsl2583_set_pm_runtime_busy() is successful so the reading
738 	 * (if applicable) is returned to user space.
739 	 */
740 	pm_ret = tsl2583_set_pm_runtime_busy(chip, false);
741 	if (pm_ret < 0)
742 		return pm_ret;
743 
744 	return ret;
745 }
746 
tsl2583_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)747 static int tsl2583_write_raw(struct iio_dev *indio_dev,
748 			     struct iio_chan_spec const *chan,
749 			     int val, int val2, long mask)
750 {
751 	struct tsl2583_chip *chip = iio_priv(indio_dev);
752 	int ret;
753 
754 	ret = tsl2583_set_pm_runtime_busy(chip, true);
755 	if (ret < 0)
756 		return ret;
757 
758 	mutex_lock(&chip->als_mutex);
759 
760 	ret = -EINVAL;
761 	switch (mask) {
762 	case IIO_CHAN_INFO_CALIBBIAS:
763 		if (chan->type == IIO_LIGHT) {
764 			chip->als_settings.als_gain_trim = val;
765 			ret = 0;
766 		}
767 		break;
768 	case IIO_CHAN_INFO_CALIBSCALE:
769 		if (chan->type == IIO_LIGHT) {
770 			unsigned int i;
771 
772 			for (i = 0; i < ARRAY_SIZE(gainadj); i++) {
773 				if (gainadj[i].mean == val) {
774 					chip->als_settings.als_gain = i;
775 					ret = tsl2583_set_als_gain(chip);
776 					break;
777 				}
778 			}
779 		}
780 		break;
781 	case IIO_CHAN_INFO_INT_TIME:
782 		if (chan->type == IIO_LIGHT && !val && val2 >= 50 &&
783 		    val2 <= 650 && !(val2 % 50)) {
784 			chip->als_settings.als_time = val2;
785 			ret = tsl2583_set_als_time(chip);
786 		}
787 		break;
788 	default:
789 		break;
790 	}
791 
792 	mutex_unlock(&chip->als_mutex);
793 
794 	if (ret < 0) {
795 		tsl2583_set_pm_runtime_busy(chip, false);
796 		return ret;
797 	}
798 
799 	ret = tsl2583_set_pm_runtime_busy(chip, false);
800 	if (ret < 0)
801 		return ret;
802 
803 	return ret;
804 }
805 
806 static const struct iio_info tsl2583_info = {
807 	.attrs = &tsl2583_attribute_group,
808 	.read_raw = tsl2583_read_raw,
809 	.write_raw = tsl2583_write_raw,
810 };
811 
tsl2583_probe(struct i2c_client * clientp,const struct i2c_device_id * idp)812 static int tsl2583_probe(struct i2c_client *clientp,
813 			 const struct i2c_device_id *idp)
814 {
815 	int ret;
816 	struct tsl2583_chip *chip;
817 	struct iio_dev *indio_dev;
818 
819 	if (!i2c_check_functionality(clientp->adapter,
820 				     I2C_FUNC_SMBUS_BYTE_DATA)) {
821 		dev_err(&clientp->dev, "%s: i2c smbus byte data functionality is unsupported\n",
822 			__func__);
823 		return -EOPNOTSUPP;
824 	}
825 
826 	indio_dev = devm_iio_device_alloc(&clientp->dev, sizeof(*chip));
827 	if (!indio_dev)
828 		return -ENOMEM;
829 
830 	chip = iio_priv(indio_dev);
831 	chip->client = clientp;
832 	i2c_set_clientdata(clientp, indio_dev);
833 
834 	mutex_init(&chip->als_mutex);
835 
836 	ret = i2c_smbus_read_byte_data(clientp,
837 				       TSL2583_CMD_REG | TSL2583_CHIPID);
838 	if (ret < 0) {
839 		dev_err(&clientp->dev,
840 			"%s: failed to read the chip ID register\n", __func__);
841 		return ret;
842 	}
843 
844 	if ((ret & TSL2583_CHIP_ID_MASK) != TSL2583_CHIP_ID) {
845 		dev_err(&clientp->dev, "%s: received an unknown chip ID %x\n",
846 			__func__, ret);
847 		return -EINVAL;
848 	}
849 
850 	indio_dev->info = &tsl2583_info;
851 	indio_dev->channels = tsl2583_channels;
852 	indio_dev->num_channels = ARRAY_SIZE(tsl2583_channels);
853 	indio_dev->modes = INDIO_DIRECT_MODE;
854 	indio_dev->name = chip->client->name;
855 
856 	pm_runtime_enable(&clientp->dev);
857 	pm_runtime_set_autosuspend_delay(&clientp->dev,
858 					 TSL2583_POWER_OFF_DELAY_MS);
859 	pm_runtime_use_autosuspend(&clientp->dev);
860 
861 	ret = iio_device_register(indio_dev);
862 	if (ret) {
863 		dev_err(&clientp->dev, "%s: iio registration failed\n",
864 			__func__);
865 		return ret;
866 	}
867 
868 	/* Load up the V2 defaults (these are hard coded defaults for now) */
869 	tsl2583_defaults(chip);
870 
871 	dev_info(&clientp->dev, "Light sensor found.\n");
872 
873 	return 0;
874 }
875 
tsl2583_remove(struct i2c_client * client)876 static void tsl2583_remove(struct i2c_client *client)
877 {
878 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
879 	struct tsl2583_chip *chip = iio_priv(indio_dev);
880 
881 	iio_device_unregister(indio_dev);
882 
883 	pm_runtime_disable(&client->dev);
884 	pm_runtime_set_suspended(&client->dev);
885 
886 	tsl2583_set_power_state(chip, TSL2583_CNTL_PWR_OFF);
887 }
888 
tsl2583_suspend(struct device * dev)889 static int tsl2583_suspend(struct device *dev)
890 {
891 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
892 	struct tsl2583_chip *chip = iio_priv(indio_dev);
893 	int ret;
894 
895 	mutex_lock(&chip->als_mutex);
896 
897 	ret = tsl2583_set_power_state(chip, TSL2583_CNTL_PWR_OFF);
898 
899 	mutex_unlock(&chip->als_mutex);
900 
901 	return ret;
902 }
903 
tsl2583_resume(struct device * dev)904 static int tsl2583_resume(struct device *dev)
905 {
906 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
907 	struct tsl2583_chip *chip = iio_priv(indio_dev);
908 	int ret;
909 
910 	mutex_lock(&chip->als_mutex);
911 
912 	ret = tsl2583_chip_init_and_power_on(indio_dev);
913 
914 	mutex_unlock(&chip->als_mutex);
915 
916 	return ret;
917 }
918 
919 static DEFINE_RUNTIME_DEV_PM_OPS(tsl2583_pm_ops, tsl2583_suspend,
920 				 tsl2583_resume, NULL);
921 
922 static const struct i2c_device_id tsl2583_idtable[] = {
923 	{ "tsl2580", 0 },
924 	{ "tsl2581", 1 },
925 	{ "tsl2583", 2 },
926 	{}
927 };
928 MODULE_DEVICE_TABLE(i2c, tsl2583_idtable);
929 
930 static const struct of_device_id tsl2583_of_match[] = {
931 	{ .compatible = "amstaos,tsl2580", },
932 	{ .compatible = "amstaos,tsl2581", },
933 	{ .compatible = "amstaos,tsl2583", },
934 	{ },
935 };
936 MODULE_DEVICE_TABLE(of, tsl2583_of_match);
937 
938 /* Driver definition */
939 static struct i2c_driver tsl2583_driver = {
940 	.driver = {
941 		.name = "tsl2583",
942 		.pm = pm_ptr(&tsl2583_pm_ops),
943 		.of_match_table = tsl2583_of_match,
944 	},
945 	.id_table = tsl2583_idtable,
946 	.probe = tsl2583_probe,
947 	.remove = tsl2583_remove,
948 };
949 module_i2c_driver(tsl2583_driver);
950 
951 MODULE_AUTHOR("J. August Brenner <jbrenner@taosinc.com>");
952 MODULE_AUTHOR("Brian Masney <masneyb@onstation.org>");
953 MODULE_DESCRIPTION("TAOS tsl2583 ambient light sensor driver");
954 MODULE_LICENSE("GPL");
955