xref: /linux/drivers/iio/light/rpr0521.c (revision 18f90d372cf35b387663f1567de701e5393f6eb5)
1 /*
2  * RPR-0521 ROHM Ambient Light and Proximity Sensor
3  *
4  * Copyright (c) 2015, Intel Corporation.
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  * IIO driver for RPR-0521RS (7-bit I2C slave address 0x38).
11  *
12  * TODO: illuminance channel
13  */
14 
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/i2c.h>
18 #include <linux/regmap.h>
19 #include <linux/delay.h>
20 #include <linux/acpi.h>
21 
22 #include <linux/iio/iio.h>
23 #include <linux/iio/buffer.h>
24 #include <linux/iio/trigger.h>
25 #include <linux/iio/trigger_consumer.h>
26 #include <linux/iio/triggered_buffer.h>
27 #include <linux/iio/sysfs.h>
28 #include <linux/pm_runtime.h>
29 
30 #define RPR0521_REG_SYSTEM_CTRL		0x40
31 #define RPR0521_REG_MODE_CTRL		0x41
32 #define RPR0521_REG_ALS_CTRL		0x42
33 #define RPR0521_REG_PXS_CTRL		0x43
34 #define RPR0521_REG_PXS_DATA		0x44 /* 16-bit, little endian */
35 #define RPR0521_REG_ALS_DATA0		0x46 /* 16-bit, little endian */
36 #define RPR0521_REG_ALS_DATA1		0x48 /* 16-bit, little endian */
37 #define RPR0521_REG_INTERRUPT		0x4A
38 #define RPR0521_REG_PS_OFFSET_LSB	0x53
39 #define RPR0521_REG_ID			0x92
40 
41 #define RPR0521_MODE_ALS_MASK		BIT(7)
42 #define RPR0521_MODE_PXS_MASK		BIT(6)
43 #define RPR0521_MODE_MEAS_TIME_MASK	GENMASK(3, 0)
44 #define RPR0521_ALS_DATA0_GAIN_MASK	GENMASK(5, 4)
45 #define RPR0521_ALS_DATA0_GAIN_SHIFT	4
46 #define RPR0521_ALS_DATA1_GAIN_MASK	GENMASK(3, 2)
47 #define RPR0521_ALS_DATA1_GAIN_SHIFT	2
48 #define RPR0521_PXS_GAIN_MASK		GENMASK(5, 4)
49 #define RPR0521_PXS_GAIN_SHIFT		4
50 #define RPR0521_PXS_PERSISTENCE_MASK	GENMASK(3, 0)
51 #define RPR0521_INTERRUPT_INT_TRIG_PS_MASK	BIT(0)
52 #define RPR0521_INTERRUPT_INT_TRIG_ALS_MASK	BIT(1)
53 #define RPR0521_INTERRUPT_INT_REASSERT_MASK	BIT(3)
54 #define RPR0521_INTERRUPT_ALS_INT_STATUS_MASK	BIT(6)
55 #define RPR0521_INTERRUPT_PS_INT_STATUS_MASK	BIT(7)
56 
57 #define RPR0521_MODE_ALS_ENABLE		BIT(7)
58 #define RPR0521_MODE_ALS_DISABLE	0x00
59 #define RPR0521_MODE_PXS_ENABLE		BIT(6)
60 #define RPR0521_MODE_PXS_DISABLE	0x00
61 #define RPR0521_PXS_PERSISTENCE_DRDY	0x00
62 
63 #define RPR0521_INTERRUPT_INT_TRIG_PS_ENABLE	BIT(0)
64 #define RPR0521_INTERRUPT_INT_TRIG_PS_DISABLE	0x00
65 #define RPR0521_INTERRUPT_INT_TRIG_ALS_ENABLE	BIT(1)
66 #define RPR0521_INTERRUPT_INT_TRIG_ALS_DISABLE	0x00
67 #define RPR0521_INTERRUPT_INT_REASSERT_ENABLE	BIT(3)
68 #define RPR0521_INTERRUPT_INT_REASSERT_DISABLE	0x00
69 
70 #define RPR0521_MANUFACT_ID		0xE0
71 #define RPR0521_DEFAULT_MEAS_TIME	0x06 /* ALS - 100ms, PXS - 100ms */
72 
73 #define RPR0521_DRV_NAME		"RPR0521"
74 #define RPR0521_IRQ_NAME		"rpr0521_event"
75 #define RPR0521_REGMAP_NAME		"rpr0521_regmap"
76 
77 #define RPR0521_SLEEP_DELAY_MS	2000
78 
79 #define RPR0521_ALS_SCALE_AVAIL "0.007812 0.015625 0.5 1"
80 #define RPR0521_PXS_SCALE_AVAIL "0.125 0.5 1"
81 
82 struct rpr0521_gain {
83 	int scale;
84 	int uscale;
85 };
86 
87 static const struct rpr0521_gain rpr0521_als_gain[4] = {
88 	{1, 0},		/* x1 */
89 	{0, 500000},	/* x2 */
90 	{0, 15625},	/* x64 */
91 	{0, 7812},	/* x128 */
92 };
93 
94 static const struct rpr0521_gain rpr0521_pxs_gain[3] = {
95 	{1, 0},		/* x1 */
96 	{0, 500000},	/* x2 */
97 	{0, 125000},	/* x4 */
98 };
99 
100 enum rpr0521_channel {
101 	RPR0521_CHAN_PXS,
102 	RPR0521_CHAN_ALS_DATA0,
103 	RPR0521_CHAN_ALS_DATA1,
104 };
105 
106 struct rpr0521_reg_desc {
107 	u8 address;
108 	u8 device_mask;
109 };
110 
111 static const struct rpr0521_reg_desc rpr0521_data_reg[] = {
112 	[RPR0521_CHAN_PXS]	= {
113 		.address	= RPR0521_REG_PXS_DATA,
114 		.device_mask	= RPR0521_MODE_PXS_MASK,
115 	},
116 	[RPR0521_CHAN_ALS_DATA0] = {
117 		.address	= RPR0521_REG_ALS_DATA0,
118 		.device_mask	= RPR0521_MODE_ALS_MASK,
119 	},
120 	[RPR0521_CHAN_ALS_DATA1] = {
121 		.address	= RPR0521_REG_ALS_DATA1,
122 		.device_mask	= RPR0521_MODE_ALS_MASK,
123 	},
124 };
125 
126 static const struct rpr0521_gain_info {
127 	u8 reg;
128 	u8 mask;
129 	u8 shift;
130 	const struct rpr0521_gain *gain;
131 	int size;
132 } rpr0521_gain[] = {
133 	[RPR0521_CHAN_PXS] = {
134 		.reg	= RPR0521_REG_PXS_CTRL,
135 		.mask	= RPR0521_PXS_GAIN_MASK,
136 		.shift	= RPR0521_PXS_GAIN_SHIFT,
137 		.gain	= rpr0521_pxs_gain,
138 		.size	= ARRAY_SIZE(rpr0521_pxs_gain),
139 	},
140 	[RPR0521_CHAN_ALS_DATA0] = {
141 		.reg	= RPR0521_REG_ALS_CTRL,
142 		.mask	= RPR0521_ALS_DATA0_GAIN_MASK,
143 		.shift	= RPR0521_ALS_DATA0_GAIN_SHIFT,
144 		.gain	= rpr0521_als_gain,
145 		.size	= ARRAY_SIZE(rpr0521_als_gain),
146 	},
147 	[RPR0521_CHAN_ALS_DATA1] = {
148 		.reg	= RPR0521_REG_ALS_CTRL,
149 		.mask	= RPR0521_ALS_DATA1_GAIN_MASK,
150 		.shift	= RPR0521_ALS_DATA1_GAIN_SHIFT,
151 		.gain	= rpr0521_als_gain,
152 		.size	= ARRAY_SIZE(rpr0521_als_gain),
153 	},
154 };
155 
156 struct rpr0521_samp_freq {
157 	int	als_hz;
158 	int	als_uhz;
159 	int	pxs_hz;
160 	int	pxs_uhz;
161 };
162 
163 static const struct rpr0521_samp_freq rpr0521_samp_freq_i[13] = {
164 /*	{ALS, PXS},		   W==currently writable option */
165 	{0, 0, 0, 0},		/* W0000, 0=standby */
166 	{0, 0, 100, 0},		/*  0001 */
167 	{0, 0, 25, 0},		/*  0010 */
168 	{0, 0, 10, 0},		/*  0011 */
169 	{0, 0, 2, 500000},	/*  0100 */
170 	{10, 0, 20, 0},		/*  0101 */
171 	{10, 0, 10, 0},		/* W0110 */
172 	{10, 0, 2, 500000},	/*  0111 */
173 	{2, 500000, 20, 0},	/*  1000, measurement 100ms, sleep 300ms */
174 	{2, 500000, 10, 0},	/*  1001, measurement 100ms, sleep 300ms */
175 	{2, 500000, 0, 0},	/*  1010, high sensitivity mode */
176 	{2, 500000, 2, 500000},	/* W1011, high sensitivity mode */
177 	{20, 0, 20, 0}	/* 1100, ALS_data x 0.5, see specification P.18 */
178 };
179 
180 struct rpr0521_data {
181 	struct i2c_client *client;
182 
183 	/* protect device params updates (e.g state, gain) */
184 	struct mutex lock;
185 
186 	/* device active status */
187 	bool als_dev_en;
188 	bool pxs_dev_en;
189 
190 	struct iio_trigger *drdy_trigger0;
191 	s64 irq_timestamp;
192 
193 	/* optimize runtime pm ops - enable/disable device only if needed */
194 	bool als_ps_need_en;
195 	bool pxs_ps_need_en;
196 	bool als_need_dis;
197 	bool pxs_need_dis;
198 
199 	struct regmap *regmap;
200 };
201 
202 static IIO_CONST_ATTR(in_intensity_scale_available, RPR0521_ALS_SCALE_AVAIL);
203 static IIO_CONST_ATTR(in_proximity_scale_available, RPR0521_PXS_SCALE_AVAIL);
204 
205 /*
206  * Start with easy freq first, whole table of freq combinations is more
207  * complicated.
208  */
209 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("2.5 10");
210 
211 static struct attribute *rpr0521_attributes[] = {
212 	&iio_const_attr_in_intensity_scale_available.dev_attr.attr,
213 	&iio_const_attr_in_proximity_scale_available.dev_attr.attr,
214 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
215 	NULL,
216 };
217 
218 static const struct attribute_group rpr0521_attribute_group = {
219 	.attrs = rpr0521_attributes,
220 };
221 
222 /* Order of the channel data in buffer */
223 enum rpr0521_scan_index_order {
224 	RPR0521_CHAN_INDEX_PXS,
225 	RPR0521_CHAN_INDEX_BOTH,
226 	RPR0521_CHAN_INDEX_IR,
227 };
228 
229 static const unsigned long rpr0521_available_scan_masks[] = {
230 	BIT(RPR0521_CHAN_INDEX_PXS) | BIT(RPR0521_CHAN_INDEX_BOTH) |
231 	BIT(RPR0521_CHAN_INDEX_IR),
232 	0
233 };
234 
235 static const struct iio_chan_spec rpr0521_channels[] = {
236 	{
237 		.type = IIO_PROXIMITY,
238 		.address = RPR0521_CHAN_PXS,
239 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
240 			BIT(IIO_CHAN_INFO_OFFSET) |
241 			BIT(IIO_CHAN_INFO_SCALE),
242 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
243 		.scan_index = RPR0521_CHAN_INDEX_PXS,
244 		.scan_type = {
245 			.sign = 'u',
246 			.realbits = 16,
247 			.storagebits = 16,
248 			.endianness = IIO_LE,
249 		},
250 	},
251 	{
252 		.type = IIO_INTENSITY,
253 		.modified = 1,
254 		.address = RPR0521_CHAN_ALS_DATA0,
255 		.channel2 = IIO_MOD_LIGHT_BOTH,
256 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
257 			BIT(IIO_CHAN_INFO_SCALE),
258 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
259 		.scan_index = RPR0521_CHAN_INDEX_BOTH,
260 		.scan_type = {
261 			.sign = 'u',
262 			.realbits = 16,
263 			.storagebits = 16,
264 			.endianness = IIO_LE,
265 		},
266 	},
267 	{
268 		.type = IIO_INTENSITY,
269 		.modified = 1,
270 		.address = RPR0521_CHAN_ALS_DATA1,
271 		.channel2 = IIO_MOD_LIGHT_IR,
272 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
273 			BIT(IIO_CHAN_INFO_SCALE),
274 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
275 		.scan_index = RPR0521_CHAN_INDEX_IR,
276 		.scan_type = {
277 			.sign = 'u',
278 			.realbits = 16,
279 			.storagebits = 16,
280 			.endianness = IIO_LE,
281 		},
282 	},
283 };
284 
285 static int rpr0521_als_enable(struct rpr0521_data *data, u8 status)
286 {
287 	int ret;
288 
289 	ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
290 				 RPR0521_MODE_ALS_MASK,
291 				 status);
292 	if (ret < 0)
293 		return ret;
294 
295 	if (status & RPR0521_MODE_ALS_MASK)
296 		data->als_dev_en = true;
297 	else
298 		data->als_dev_en = false;
299 
300 	return 0;
301 }
302 
303 static int rpr0521_pxs_enable(struct rpr0521_data *data, u8 status)
304 {
305 	int ret;
306 
307 	ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
308 				 RPR0521_MODE_PXS_MASK,
309 				 status);
310 	if (ret < 0)
311 		return ret;
312 
313 	if (status & RPR0521_MODE_PXS_MASK)
314 		data->pxs_dev_en = true;
315 	else
316 		data->pxs_dev_en = false;
317 
318 	return 0;
319 }
320 
321 /**
322  * rpr0521_set_power_state - handles runtime PM state and sensors enabled status
323  *
324  * @data: rpr0521 device private data
325  * @on: state to be set for devices in @device_mask
326  * @device_mask: bitmask specifying for which device we need to update @on state
327  *
328  * Calls for this function must be balanced so that each ON should have matching
329  * OFF. Otherwise pm usage_count gets out of sync.
330  */
331 static int rpr0521_set_power_state(struct rpr0521_data *data, bool on,
332 				   u8 device_mask)
333 {
334 #ifdef CONFIG_PM
335 	int ret;
336 
337 	if (device_mask & RPR0521_MODE_ALS_MASK) {
338 		data->als_ps_need_en = on;
339 		data->als_need_dis = !on;
340 	}
341 
342 	if (device_mask & RPR0521_MODE_PXS_MASK) {
343 		data->pxs_ps_need_en = on;
344 		data->pxs_need_dis = !on;
345 	}
346 
347 	/*
348 	 * On: _resume() is called only when we are suspended
349 	 * Off: _suspend() is called after delay if _resume() is not
350 	 * called before that.
351 	 * Note: If either measurement is re-enabled before _suspend(),
352 	 * both stay enabled until _suspend().
353 	 */
354 	if (on) {
355 		ret = pm_runtime_get_sync(&data->client->dev);
356 	} else {
357 		pm_runtime_mark_last_busy(&data->client->dev);
358 		ret = pm_runtime_put_autosuspend(&data->client->dev);
359 	}
360 	if (ret < 0) {
361 		dev_err(&data->client->dev,
362 			"Failed: rpr0521_set_power_state for %d, ret %d\n",
363 			on, ret);
364 		if (on)
365 			pm_runtime_put_noidle(&data->client->dev);
366 
367 		return ret;
368 	}
369 
370 	if (on) {
371 		/* If _resume() was not called, enable measurement now. */
372 		if (data->als_ps_need_en) {
373 			ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
374 			if (ret)
375 				return ret;
376 			data->als_ps_need_en = false;
377 		}
378 
379 		if (data->pxs_ps_need_en) {
380 			ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
381 			if (ret)
382 				return ret;
383 			data->pxs_ps_need_en = false;
384 		}
385 	}
386 #endif
387 	return 0;
388 }
389 
390 /* Interrupt register tells if this sensor caused the interrupt or not. */
391 static inline bool rpr0521_is_triggered(struct rpr0521_data *data)
392 {
393 	int ret;
394 	int reg;
395 
396 	ret = regmap_read(data->regmap, RPR0521_REG_INTERRUPT, &reg);
397 	if (ret < 0)
398 		return false;   /* Reg read failed. */
399 	if (reg &
400 	    (RPR0521_INTERRUPT_ALS_INT_STATUS_MASK |
401 	    RPR0521_INTERRUPT_PS_INT_STATUS_MASK))
402 		return true;
403 	else
404 		return false;   /* Int not from this sensor. */
405 }
406 
407 /* IRQ to trigger handler */
408 static irqreturn_t rpr0521_drdy_irq_handler(int irq, void *private)
409 {
410 	struct iio_dev *indio_dev = private;
411 	struct rpr0521_data *data = iio_priv(indio_dev);
412 
413 	data->irq_timestamp = iio_get_time_ns(indio_dev);
414 	/*
415 	 * We need to wake the thread to read the interrupt reg. It
416 	 * is not possible to do that here because regmap_read takes a
417 	 * mutex.
418 	 */
419 
420 	return IRQ_WAKE_THREAD;
421 }
422 
423 static irqreturn_t rpr0521_drdy_irq_thread(int irq, void *private)
424 {
425 	struct iio_dev *indio_dev = private;
426 	struct rpr0521_data *data = iio_priv(indio_dev);
427 
428 	if (rpr0521_is_triggered(data)) {
429 		iio_trigger_poll_chained(data->drdy_trigger0);
430 		return IRQ_HANDLED;
431 	}
432 
433 	return IRQ_NONE;
434 }
435 
436 static irqreturn_t rpr0521_trigger_consumer_store_time(int irq, void *p)
437 {
438 	struct iio_poll_func *pf = p;
439 	struct iio_dev *indio_dev = pf->indio_dev;
440 
441 	/* Other trigger polls store time here. */
442 	if (!iio_trigger_using_own(indio_dev))
443 		pf->timestamp = iio_get_time_ns(indio_dev);
444 
445 	return IRQ_WAKE_THREAD;
446 }
447 
448 static irqreturn_t rpr0521_trigger_consumer_handler(int irq, void *p)
449 {
450 	struct iio_poll_func *pf = p;
451 	struct iio_dev *indio_dev = pf->indio_dev;
452 	struct rpr0521_data *data = iio_priv(indio_dev);
453 	int err;
454 
455 	u8 buffer[16]; /* 3 16-bit channels + padding + ts */
456 
457 	/* Use irq timestamp when reasonable. */
458 	if (iio_trigger_using_own(indio_dev) && data->irq_timestamp) {
459 		pf->timestamp = data->irq_timestamp;
460 		data->irq_timestamp = 0;
461 	}
462 	/* Other chained trigger polls get timestamp only here. */
463 	if (!pf->timestamp)
464 		pf->timestamp = iio_get_time_ns(indio_dev);
465 
466 	err = regmap_bulk_read(data->regmap, RPR0521_REG_PXS_DATA,
467 		&buffer,
468 		(3 * 2) + 1);	/* 3 * 16-bit + (discarded) int clear reg. */
469 	if (!err)
470 		iio_push_to_buffers_with_timestamp(indio_dev,
471 						   buffer, pf->timestamp);
472 	else
473 		dev_err(&data->client->dev,
474 			"Trigger consumer can't read from sensor.\n");
475 	pf->timestamp = 0;
476 
477 	iio_trigger_notify_done(indio_dev->trig);
478 
479 	return IRQ_HANDLED;
480 }
481 
482 static int rpr0521_write_int_enable(struct rpr0521_data *data)
483 {
484 	int err;
485 
486 	/* Interrupt after each measurement */
487 	err = regmap_update_bits(data->regmap, RPR0521_REG_PXS_CTRL,
488 		RPR0521_PXS_PERSISTENCE_MASK,
489 		RPR0521_PXS_PERSISTENCE_DRDY);
490 	if (err) {
491 		dev_err(&data->client->dev, "PS control reg write fail.\n");
492 		return -EBUSY;
493 		}
494 
495 	/* Ignore latch and mode because of drdy */
496 	err = regmap_write(data->regmap, RPR0521_REG_INTERRUPT,
497 		RPR0521_INTERRUPT_INT_REASSERT_DISABLE |
498 		RPR0521_INTERRUPT_INT_TRIG_ALS_DISABLE |
499 		RPR0521_INTERRUPT_INT_TRIG_PS_ENABLE
500 		);
501 	if (err) {
502 		dev_err(&data->client->dev, "Interrupt setup write fail.\n");
503 		return -EBUSY;
504 		}
505 
506 	return 0;
507 }
508 
509 static int rpr0521_write_int_disable(struct rpr0521_data *data)
510 {
511 	/* Don't care of clearing mode, assert and latch. */
512 	return regmap_write(data->regmap, RPR0521_REG_INTERRUPT,
513 				RPR0521_INTERRUPT_INT_TRIG_ALS_DISABLE |
514 				RPR0521_INTERRUPT_INT_TRIG_PS_DISABLE
515 				);
516 }
517 
518 /*
519  * Trigger producer enable / disable. Note that there will be trigs only when
520  * measurement data is ready to be read.
521  */
522 static int rpr0521_pxs_drdy_set_state(struct iio_trigger *trigger,
523 	bool enable_drdy)
524 {
525 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trigger);
526 	struct rpr0521_data *data = iio_priv(indio_dev);
527 	int err;
528 
529 	if (enable_drdy)
530 		err = rpr0521_write_int_enable(data);
531 	else
532 		err = rpr0521_write_int_disable(data);
533 	if (err)
534 		dev_err(&data->client->dev, "rpr0521_pxs_drdy_set_state failed\n");
535 
536 	return err;
537 }
538 
539 static const struct iio_trigger_ops rpr0521_trigger_ops = {
540 	.set_trigger_state = rpr0521_pxs_drdy_set_state,
541 	};
542 
543 
544 static int rpr0521_buffer_preenable(struct iio_dev *indio_dev)
545 {
546 	int err;
547 	struct rpr0521_data *data = iio_priv(indio_dev);
548 
549 	mutex_lock(&data->lock);
550 	err = rpr0521_set_power_state(data, true,
551 		(RPR0521_MODE_PXS_MASK | RPR0521_MODE_ALS_MASK));
552 	mutex_unlock(&data->lock);
553 	if (err)
554 		dev_err(&data->client->dev, "_buffer_preenable fail\n");
555 
556 	return err;
557 }
558 
559 static int rpr0521_buffer_postdisable(struct iio_dev *indio_dev)
560 {
561 	int err;
562 	struct rpr0521_data *data = iio_priv(indio_dev);
563 
564 	mutex_lock(&data->lock);
565 	err = rpr0521_set_power_state(data, false,
566 		(RPR0521_MODE_PXS_MASK | RPR0521_MODE_ALS_MASK));
567 	mutex_unlock(&data->lock);
568 	if (err)
569 		dev_err(&data->client->dev, "_buffer_postdisable fail\n");
570 
571 	return err;
572 }
573 
574 static const struct iio_buffer_setup_ops rpr0521_buffer_setup_ops = {
575 	.preenable = rpr0521_buffer_preenable,
576 	.postenable = iio_triggered_buffer_postenable,
577 	.predisable = iio_triggered_buffer_predisable,
578 	.postdisable = rpr0521_buffer_postdisable,
579 };
580 
581 static int rpr0521_get_gain(struct rpr0521_data *data, int chan,
582 			    int *val, int *val2)
583 {
584 	int ret, reg, idx;
585 
586 	ret = regmap_read(data->regmap, rpr0521_gain[chan].reg, &reg);
587 	if (ret < 0)
588 		return ret;
589 
590 	idx = (rpr0521_gain[chan].mask & reg) >> rpr0521_gain[chan].shift;
591 	*val = rpr0521_gain[chan].gain[idx].scale;
592 	*val2 = rpr0521_gain[chan].gain[idx].uscale;
593 
594 	return 0;
595 }
596 
597 static int rpr0521_set_gain(struct rpr0521_data *data, int chan,
598 			    int val, int val2)
599 {
600 	int i, idx = -EINVAL;
601 
602 	/* get gain index */
603 	for (i = 0; i < rpr0521_gain[chan].size; i++)
604 		if (val == rpr0521_gain[chan].gain[i].scale &&
605 		    val2 == rpr0521_gain[chan].gain[i].uscale) {
606 			idx = i;
607 			break;
608 		}
609 
610 	if (idx < 0)
611 		return idx;
612 
613 	return regmap_update_bits(data->regmap, rpr0521_gain[chan].reg,
614 				  rpr0521_gain[chan].mask,
615 				  idx << rpr0521_gain[chan].shift);
616 }
617 
618 static int rpr0521_read_samp_freq(struct rpr0521_data *data,
619 				enum iio_chan_type chan_type,
620 			    int *val, int *val2)
621 {
622 	int reg, ret;
623 
624 	ret = regmap_read(data->regmap, RPR0521_REG_MODE_CTRL, &reg);
625 	if (ret < 0)
626 		return ret;
627 
628 	reg &= RPR0521_MODE_MEAS_TIME_MASK;
629 	if (reg >= ARRAY_SIZE(rpr0521_samp_freq_i))
630 		return -EINVAL;
631 
632 	switch (chan_type) {
633 	case IIO_INTENSITY:
634 		*val = rpr0521_samp_freq_i[reg].als_hz;
635 		*val2 = rpr0521_samp_freq_i[reg].als_uhz;
636 		return 0;
637 
638 	case IIO_PROXIMITY:
639 		*val = rpr0521_samp_freq_i[reg].pxs_hz;
640 		*val2 = rpr0521_samp_freq_i[reg].pxs_uhz;
641 		return 0;
642 
643 	default:
644 		return -EINVAL;
645 	}
646 }
647 
648 static int rpr0521_write_samp_freq_common(struct rpr0521_data *data,
649 				enum iio_chan_type chan_type,
650 				int val, int val2)
651 {
652 	int i;
653 
654 	/*
655 	 * Ignore channel
656 	 * both pxs and als are setup only to same freq because of simplicity
657 	 */
658 	switch (val) {
659 	case 0:
660 		i = 0;
661 		break;
662 
663 	case 2:
664 		if (val2 != 500000)
665 			return -EINVAL;
666 
667 		i = 11;
668 		break;
669 
670 	case 10:
671 		i = 6;
672 		break;
673 
674 	default:
675 		return -EINVAL;
676 	}
677 
678 	return regmap_update_bits(data->regmap,
679 		RPR0521_REG_MODE_CTRL,
680 		RPR0521_MODE_MEAS_TIME_MASK,
681 		i);
682 }
683 
684 static int rpr0521_read_ps_offset(struct rpr0521_data *data, int *offset)
685 {
686 	int ret;
687 	__le16 buffer;
688 
689 	ret = regmap_bulk_read(data->regmap,
690 		RPR0521_REG_PS_OFFSET_LSB, &buffer, sizeof(buffer));
691 
692 	if (ret < 0) {
693 		dev_err(&data->client->dev, "Failed to read PS OFFSET register\n");
694 		return ret;
695 	}
696 	*offset = le16_to_cpu(buffer);
697 
698 	return ret;
699 }
700 
701 static int rpr0521_write_ps_offset(struct rpr0521_data *data, int offset)
702 {
703 	int ret;
704 	__le16 buffer;
705 
706 	buffer = cpu_to_le16(offset & 0x3ff);
707 	ret = regmap_raw_write(data->regmap,
708 		RPR0521_REG_PS_OFFSET_LSB, &buffer, sizeof(buffer));
709 
710 	if (ret < 0) {
711 		dev_err(&data->client->dev, "Failed to write PS OFFSET register\n");
712 		return ret;
713 	}
714 
715 	return ret;
716 }
717 
718 static int rpr0521_read_raw(struct iio_dev *indio_dev,
719 			    struct iio_chan_spec const *chan, int *val,
720 			    int *val2, long mask)
721 {
722 	struct rpr0521_data *data = iio_priv(indio_dev);
723 	int ret;
724 	int busy;
725 	u8 device_mask;
726 	__le16 raw_data;
727 
728 	switch (mask) {
729 	case IIO_CHAN_INFO_RAW:
730 		if (chan->type != IIO_INTENSITY && chan->type != IIO_PROXIMITY)
731 			return -EINVAL;
732 
733 		busy = iio_device_claim_direct_mode(indio_dev);
734 		if (busy)
735 			return -EBUSY;
736 
737 		device_mask = rpr0521_data_reg[chan->address].device_mask;
738 
739 		mutex_lock(&data->lock);
740 		ret = rpr0521_set_power_state(data, true, device_mask);
741 		if (ret < 0)
742 			goto rpr0521_read_raw_out;
743 
744 		ret = regmap_bulk_read(data->regmap,
745 				       rpr0521_data_reg[chan->address].address,
746 				       &raw_data, sizeof(raw_data));
747 		if (ret < 0) {
748 			rpr0521_set_power_state(data, false, device_mask);
749 			goto rpr0521_read_raw_out;
750 		}
751 
752 		ret = rpr0521_set_power_state(data, false, device_mask);
753 
754 rpr0521_read_raw_out:
755 		mutex_unlock(&data->lock);
756 		iio_device_release_direct_mode(indio_dev);
757 		if (ret < 0)
758 			return ret;
759 
760 		*val = le16_to_cpu(raw_data);
761 
762 		return IIO_VAL_INT;
763 
764 	case IIO_CHAN_INFO_SCALE:
765 		mutex_lock(&data->lock);
766 		ret = rpr0521_get_gain(data, chan->address, val, val2);
767 		mutex_unlock(&data->lock);
768 		if (ret < 0)
769 			return ret;
770 
771 		return IIO_VAL_INT_PLUS_MICRO;
772 
773 	case IIO_CHAN_INFO_SAMP_FREQ:
774 		mutex_lock(&data->lock);
775 		ret = rpr0521_read_samp_freq(data, chan->type, val, val2);
776 		mutex_unlock(&data->lock);
777 		if (ret < 0)
778 			return ret;
779 
780 		return IIO_VAL_INT_PLUS_MICRO;
781 
782 	case IIO_CHAN_INFO_OFFSET:
783 		mutex_lock(&data->lock);
784 		ret = rpr0521_read_ps_offset(data, val);
785 		mutex_unlock(&data->lock);
786 		if (ret < 0)
787 			return ret;
788 
789 		return IIO_VAL_INT;
790 
791 	default:
792 		return -EINVAL;
793 	}
794 }
795 
796 static int rpr0521_write_raw(struct iio_dev *indio_dev,
797 			     struct iio_chan_spec const *chan, int val,
798 			     int val2, long mask)
799 {
800 	struct rpr0521_data *data = iio_priv(indio_dev);
801 	int ret;
802 
803 	switch (mask) {
804 	case IIO_CHAN_INFO_SCALE:
805 		mutex_lock(&data->lock);
806 		ret = rpr0521_set_gain(data, chan->address, val, val2);
807 		mutex_unlock(&data->lock);
808 
809 		return ret;
810 
811 	case IIO_CHAN_INFO_SAMP_FREQ:
812 		mutex_lock(&data->lock);
813 		ret = rpr0521_write_samp_freq_common(data, chan->type,
814 						     val, val2);
815 		mutex_unlock(&data->lock);
816 
817 		return ret;
818 
819 	case IIO_CHAN_INFO_OFFSET:
820 		mutex_lock(&data->lock);
821 		ret = rpr0521_write_ps_offset(data, val);
822 		mutex_unlock(&data->lock);
823 
824 		return ret;
825 
826 	default:
827 		return -EINVAL;
828 	}
829 }
830 
831 static const struct iio_info rpr0521_info = {
832 	.read_raw	= rpr0521_read_raw,
833 	.write_raw	= rpr0521_write_raw,
834 	.attrs		= &rpr0521_attribute_group,
835 };
836 
837 static int rpr0521_init(struct rpr0521_data *data)
838 {
839 	int ret;
840 	int id;
841 
842 	ret = regmap_read(data->regmap, RPR0521_REG_ID, &id);
843 	if (ret < 0) {
844 		dev_err(&data->client->dev, "Failed to read REG_ID register\n");
845 		return ret;
846 	}
847 
848 	if (id != RPR0521_MANUFACT_ID) {
849 		dev_err(&data->client->dev, "Wrong id, got %x, expected %x\n",
850 			id, RPR0521_MANUFACT_ID);
851 		return -ENODEV;
852 	}
853 
854 	/* set default measurement time - 100 ms for both ALS and PS */
855 	ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
856 				 RPR0521_MODE_MEAS_TIME_MASK,
857 				 RPR0521_DEFAULT_MEAS_TIME);
858 	if (ret) {
859 		pr_err("regmap_update_bits returned %d\n", ret);
860 		return ret;
861 	}
862 
863 #ifndef CONFIG_PM
864 	ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
865 	if (ret < 0)
866 		return ret;
867 	ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
868 	if (ret < 0)
869 		return ret;
870 #endif
871 
872 	data->irq_timestamp = 0;
873 
874 	return 0;
875 }
876 
877 static int rpr0521_poweroff(struct rpr0521_data *data)
878 {
879 	int ret;
880 	int tmp;
881 
882 	ret = regmap_update_bits(data->regmap, RPR0521_REG_MODE_CTRL,
883 				 RPR0521_MODE_ALS_MASK |
884 				 RPR0521_MODE_PXS_MASK,
885 				 RPR0521_MODE_ALS_DISABLE |
886 				 RPR0521_MODE_PXS_DISABLE);
887 	if (ret < 0)
888 		return ret;
889 
890 	data->als_dev_en = false;
891 	data->pxs_dev_en = false;
892 
893 	/*
894 	 * Int pin keeps state after power off. Set pin to high impedance
895 	 * mode to prevent power drain.
896 	 */
897 	ret = regmap_read(data->regmap, RPR0521_REG_INTERRUPT, &tmp);
898 	if (ret) {
899 		dev_err(&data->client->dev, "Failed to reset int pin.\n");
900 		return ret;
901 	}
902 
903 	return 0;
904 }
905 
906 static bool rpr0521_is_volatile_reg(struct device *dev, unsigned int reg)
907 {
908 	switch (reg) {
909 	case RPR0521_REG_MODE_CTRL:
910 	case RPR0521_REG_ALS_CTRL:
911 	case RPR0521_REG_PXS_CTRL:
912 		return false;
913 	default:
914 		return true;
915 	}
916 }
917 
918 static const struct regmap_config rpr0521_regmap_config = {
919 	.name		= RPR0521_REGMAP_NAME,
920 
921 	.reg_bits	= 8,
922 	.val_bits	= 8,
923 
924 	.max_register	= RPR0521_REG_ID,
925 	.cache_type	= REGCACHE_RBTREE,
926 	.volatile_reg	= rpr0521_is_volatile_reg,
927 };
928 
929 static int rpr0521_probe(struct i2c_client *client,
930 			 const struct i2c_device_id *id)
931 {
932 	struct rpr0521_data *data;
933 	struct iio_dev *indio_dev;
934 	struct regmap *regmap;
935 	int ret;
936 
937 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
938 	if (!indio_dev)
939 		return -ENOMEM;
940 
941 	regmap = devm_regmap_init_i2c(client, &rpr0521_regmap_config);
942 	if (IS_ERR(regmap)) {
943 		dev_err(&client->dev, "regmap_init failed!\n");
944 		return PTR_ERR(regmap);
945 	}
946 
947 	data = iio_priv(indio_dev);
948 	i2c_set_clientdata(client, indio_dev);
949 	data->client = client;
950 	data->regmap = regmap;
951 
952 	mutex_init(&data->lock);
953 
954 	indio_dev->dev.parent = &client->dev;
955 	indio_dev->info = &rpr0521_info;
956 	indio_dev->name = RPR0521_DRV_NAME;
957 	indio_dev->channels = rpr0521_channels;
958 	indio_dev->num_channels = ARRAY_SIZE(rpr0521_channels);
959 	indio_dev->modes = INDIO_DIRECT_MODE;
960 
961 	ret = rpr0521_init(data);
962 	if (ret < 0) {
963 		dev_err(&client->dev, "rpr0521 chip init failed\n");
964 		return ret;
965 	}
966 
967 	ret = pm_runtime_set_active(&client->dev);
968 	if (ret < 0)
969 		goto err_poweroff;
970 
971 	pm_runtime_enable(&client->dev);
972 	pm_runtime_set_autosuspend_delay(&client->dev, RPR0521_SLEEP_DELAY_MS);
973 	pm_runtime_use_autosuspend(&client->dev);
974 
975 	/*
976 	 * If sensor write/read is needed in _probe after _use_autosuspend,
977 	 * sensor needs to be _resumed first using rpr0521_set_power_state().
978 	 */
979 
980 	/* IRQ to trigger setup */
981 	if (client->irq) {
982 		/* Trigger0 producer setup */
983 		data->drdy_trigger0 = devm_iio_trigger_alloc(
984 			indio_dev->dev.parent,
985 			"%s-dev%d", indio_dev->name, indio_dev->id);
986 		if (!data->drdy_trigger0) {
987 			ret = -ENOMEM;
988 			goto err_pm_disable;
989 		}
990 		data->drdy_trigger0->dev.parent = indio_dev->dev.parent;
991 		data->drdy_trigger0->ops = &rpr0521_trigger_ops;
992 		indio_dev->available_scan_masks = rpr0521_available_scan_masks;
993 		iio_trigger_set_drvdata(data->drdy_trigger0, indio_dev);
994 
995 		/* Ties irq to trigger producer handler. */
996 		ret = devm_request_threaded_irq(&client->dev, client->irq,
997 			rpr0521_drdy_irq_handler, rpr0521_drdy_irq_thread,
998 			IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
999 			RPR0521_IRQ_NAME, indio_dev);
1000 		if (ret < 0) {
1001 			dev_err(&client->dev, "request irq %d for trigger0 failed\n",
1002 				client->irq);
1003 			goto err_pm_disable;
1004 			}
1005 
1006 		ret = devm_iio_trigger_register(indio_dev->dev.parent,
1007 						data->drdy_trigger0);
1008 		if (ret) {
1009 			dev_err(&client->dev, "iio trigger register failed\n");
1010 			goto err_pm_disable;
1011 		}
1012 
1013 		/*
1014 		 * Now whole pipe from physical interrupt (irq defined by
1015 		 * devicetree to device) to trigger0 output is set up.
1016 		 */
1017 
1018 		/* Trigger consumer setup */
1019 		ret = devm_iio_triggered_buffer_setup(indio_dev->dev.parent,
1020 			indio_dev,
1021 			rpr0521_trigger_consumer_store_time,
1022 			rpr0521_trigger_consumer_handler,
1023 			&rpr0521_buffer_setup_ops);
1024 		if (ret < 0) {
1025 			dev_err(&client->dev, "iio triggered buffer setup failed\n");
1026 			goto err_pm_disable;
1027 		}
1028 	}
1029 
1030 	ret = iio_device_register(indio_dev);
1031 	if (ret)
1032 		goto err_pm_disable;
1033 
1034 	return 0;
1035 
1036 err_pm_disable:
1037 	pm_runtime_disable(&client->dev);
1038 	pm_runtime_set_suspended(&client->dev);
1039 	pm_runtime_put_noidle(&client->dev);
1040 err_poweroff:
1041 	rpr0521_poweroff(data);
1042 
1043 	return ret;
1044 }
1045 
1046 static int rpr0521_remove(struct i2c_client *client)
1047 {
1048 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
1049 
1050 	iio_device_unregister(indio_dev);
1051 
1052 	pm_runtime_disable(&client->dev);
1053 	pm_runtime_set_suspended(&client->dev);
1054 	pm_runtime_put_noidle(&client->dev);
1055 
1056 	rpr0521_poweroff(iio_priv(indio_dev));
1057 
1058 	return 0;
1059 }
1060 
1061 #ifdef CONFIG_PM
1062 static int rpr0521_runtime_suspend(struct device *dev)
1063 {
1064 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1065 	struct rpr0521_data *data = iio_priv(indio_dev);
1066 	int ret;
1067 
1068 	mutex_lock(&data->lock);
1069 	/* If measurements are enabled, enable them on resume */
1070 	if (!data->als_need_dis)
1071 		data->als_ps_need_en = data->als_dev_en;
1072 	if (!data->pxs_need_dis)
1073 		data->pxs_ps_need_en = data->pxs_dev_en;
1074 
1075 	/* disable channels and sets {als,pxs}_dev_en to false */
1076 	ret = rpr0521_poweroff(data);
1077 	regcache_mark_dirty(data->regmap);
1078 	mutex_unlock(&data->lock);
1079 
1080 	return ret;
1081 }
1082 
1083 static int rpr0521_runtime_resume(struct device *dev)
1084 {
1085 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1086 	struct rpr0521_data *data = iio_priv(indio_dev);
1087 	int ret;
1088 
1089 	regcache_sync(data->regmap);
1090 	if (data->als_ps_need_en) {
1091 		ret = rpr0521_als_enable(data, RPR0521_MODE_ALS_ENABLE);
1092 		if (ret < 0)
1093 			return ret;
1094 		data->als_ps_need_en = false;
1095 	}
1096 
1097 	if (data->pxs_ps_need_en) {
1098 		ret = rpr0521_pxs_enable(data, RPR0521_MODE_PXS_ENABLE);
1099 		if (ret < 0)
1100 			return ret;
1101 		data->pxs_ps_need_en = false;
1102 	}
1103 	msleep(100);	//wait for first measurement result
1104 
1105 	return 0;
1106 }
1107 #endif
1108 
1109 static const struct dev_pm_ops rpr0521_pm_ops = {
1110 	SET_RUNTIME_PM_OPS(rpr0521_runtime_suspend,
1111 			   rpr0521_runtime_resume, NULL)
1112 };
1113 
1114 static const struct acpi_device_id rpr0521_acpi_match[] = {
1115 	{"RPR0521", 0},
1116 	{ }
1117 };
1118 MODULE_DEVICE_TABLE(acpi, rpr0521_acpi_match);
1119 
1120 static const struct i2c_device_id rpr0521_id[] = {
1121 	{"rpr0521", 0},
1122 	{ }
1123 };
1124 
1125 MODULE_DEVICE_TABLE(i2c, rpr0521_id);
1126 
1127 static struct i2c_driver rpr0521_driver = {
1128 	.driver = {
1129 		.name	= RPR0521_DRV_NAME,
1130 		.pm	= &rpr0521_pm_ops,
1131 		.acpi_match_table = ACPI_PTR(rpr0521_acpi_match),
1132 	},
1133 	.probe		= rpr0521_probe,
1134 	.remove		= rpr0521_remove,
1135 	.id_table	= rpr0521_id,
1136 };
1137 
1138 module_i2c_driver(rpr0521_driver);
1139 
1140 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
1141 MODULE_DESCRIPTION("RPR0521 ROHM Ambient Light and Proximity Sensor driver");
1142 MODULE_LICENSE("GPL v2");
1143