xref: /linux/drivers/iio/adc/ina2xx-adc.c (revision 110e6f26af80dfd90b6e5c645b1aed7228aa580d)
1 /*
2  * INA2XX Current and Power Monitors
3  *
4  * Copyright 2015 Baylibre SAS.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * Based on linux/drivers/iio/adc/ad7291.c
11  * Copyright 2010-2011 Analog Devices Inc.
12  *
13  * Based on linux/drivers/hwmon/ina2xx.c
14  * Copyright 2012 Lothar Felten <l-felten@ti.com>
15  *
16  * Licensed under the GPL-2 or later.
17  *
18  * IIO driver for INA219-220-226-230-231
19  *
20  * Configurable 7-bit I2C slave address from 0x40 to 0x4F
21  */
22 
23 #include <linux/delay.h>
24 #include <linux/i2c.h>
25 #include <linux/iio/kfifo_buf.h>
26 #include <linux/iio/sysfs.h>
27 #include <linux/kthread.h>
28 #include <linux/module.h>
29 #include <linux/regmap.h>
30 #include <linux/util_macros.h>
31 
32 #include <linux/platform_data/ina2xx.h>
33 
34 /* INA2XX registers definition */
35 #define INA2XX_CONFIG                   0x00
36 #define INA2XX_SHUNT_VOLTAGE            0x01	/* readonly */
37 #define INA2XX_BUS_VOLTAGE              0x02	/* readonly */
38 #define INA2XX_POWER                    0x03	/* readonly */
39 #define INA2XX_CURRENT                  0x04	/* readonly */
40 #define INA2XX_CALIBRATION              0x05
41 
42 #define INA226_ALERT_MASK		GENMASK(2, 1)
43 #define INA266_CVRF			BIT(3)
44 
45 #define INA2XX_MAX_REGISTERS            8
46 
47 /* settings - depend on use case */
48 #define INA219_CONFIG_DEFAULT           0x399F	/* PGA=8 */
49 #define INA226_CONFIG_DEFAULT           0x4327
50 #define INA226_DEFAULT_AVG              4
51 #define INA226_DEFAULT_IT		1110
52 
53 #define INA2XX_RSHUNT_DEFAULT           10000
54 
55 /*
56  * bit mask for reading the averaging setting in the configuration register
57  * FIXME: use regmap_fields.
58  */
59 #define INA2XX_MODE_MASK	GENMASK(3, 0)
60 
61 #define INA226_AVG_MASK		GENMASK(11, 9)
62 #define INA226_SHIFT_AVG(val)	((val) << 9)
63 
64 /* Integration time for VBus */
65 #define INA226_ITB_MASK		GENMASK(8, 6)
66 #define INA226_SHIFT_ITB(val)	((val) << 6)
67 
68 /* Integration time for VShunt */
69 #define INA226_ITS_MASK		GENMASK(5, 3)
70 #define INA226_SHIFT_ITS(val)	((val) << 3)
71 
72 /* Cosmetic macro giving the sampling period for a full P=UxI cycle */
73 #define SAMPLING_PERIOD(c)	((c->int_time_vbus + c->int_time_vshunt) \
74 				 * c->avg)
75 
76 static bool ina2xx_is_writeable_reg(struct device *dev, unsigned int reg)
77 {
78 	return (reg == INA2XX_CONFIG) || (reg > INA2XX_CURRENT);
79 }
80 
81 static bool ina2xx_is_volatile_reg(struct device *dev, unsigned int reg)
82 {
83 	return (reg != INA2XX_CONFIG);
84 }
85 
86 static inline bool is_signed_reg(unsigned int reg)
87 {
88 	return (reg == INA2XX_SHUNT_VOLTAGE) || (reg == INA2XX_CURRENT);
89 }
90 
91 static const struct regmap_config ina2xx_regmap_config = {
92 	.reg_bits = 8,
93 	.val_bits = 16,
94 	.max_register = INA2XX_MAX_REGISTERS,
95 	.writeable_reg = ina2xx_is_writeable_reg,
96 	.volatile_reg = ina2xx_is_volatile_reg,
97 };
98 
99 enum ina2xx_ids { ina219, ina226 };
100 
101 struct ina2xx_config {
102 	u16 config_default;
103 	int calibration_factor;
104 	int shunt_div;
105 	int bus_voltage_shift;
106 	int bus_voltage_lsb;	/* uV */
107 	int power_lsb;		/* uW */
108 };
109 
110 struct ina2xx_chip_info {
111 	struct regmap *regmap;
112 	struct task_struct *task;
113 	const struct ina2xx_config *config;
114 	struct mutex state_lock;
115 	unsigned int shunt_resistor;
116 	int avg;
117 	s64 prev_ns; /* track buffer capture time, check for underruns */
118 	int int_time_vbus; /* Bus voltage integration time uS */
119 	int int_time_vshunt; /* Shunt voltage integration time uS */
120 	bool allow_async_readout;
121 };
122 
123 static const struct ina2xx_config ina2xx_config[] = {
124 	[ina219] = {
125 		.config_default = INA219_CONFIG_DEFAULT,
126 		.calibration_factor = 40960000,
127 		.shunt_div = 100,
128 		.bus_voltage_shift = 3,
129 		.bus_voltage_lsb = 4000,
130 		.power_lsb = 20000,
131 	},
132 	[ina226] = {
133 		.config_default = INA226_CONFIG_DEFAULT,
134 		.calibration_factor = 5120000,
135 		.shunt_div = 400,
136 		.bus_voltage_shift = 0,
137 		.bus_voltage_lsb = 1250,
138 		.power_lsb = 25000,
139 	},
140 };
141 
142 static int ina2xx_read_raw(struct iio_dev *indio_dev,
143 			   struct iio_chan_spec const *chan,
144 			   int *val, int *val2, long mask)
145 {
146 	int ret;
147 	struct ina2xx_chip_info *chip = iio_priv(indio_dev);
148 	unsigned int regval;
149 
150 	switch (mask) {
151 	case IIO_CHAN_INFO_RAW:
152 		ret = regmap_read(chip->regmap, chan->address, &regval);
153 		if (ret)
154 			return ret;
155 
156 		if (is_signed_reg(chan->address))
157 			*val = (s16) regval;
158 		else
159 			*val  = regval;
160 
161 		return IIO_VAL_INT;
162 
163 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
164 		*val = chip->avg;
165 		return IIO_VAL_INT;
166 
167 	case IIO_CHAN_INFO_INT_TIME:
168 		*val = 0;
169 		if (chan->address == INA2XX_SHUNT_VOLTAGE)
170 			*val2 = chip->int_time_vshunt;
171 		else
172 			*val2 = chip->int_time_vbus;
173 
174 		return IIO_VAL_INT_PLUS_MICRO;
175 
176 	case IIO_CHAN_INFO_SAMP_FREQ:
177 		/*
178 		 * Sample freq is read only, it is a consequence of
179 		 * 1/AVG*(CT_bus+CT_shunt).
180 		 */
181 		*val = DIV_ROUND_CLOSEST(1000000, SAMPLING_PERIOD(chip));
182 
183 		return IIO_VAL_INT;
184 
185 	case IIO_CHAN_INFO_SCALE:
186 		switch (chan->address) {
187 		case INA2XX_SHUNT_VOLTAGE:
188 			/* processed (mV) = raw*1000/shunt_div */
189 			*val2 = chip->config->shunt_div;
190 			*val = 1000;
191 			return IIO_VAL_FRACTIONAL;
192 
193 		case INA2XX_BUS_VOLTAGE:
194 			/* processed (mV) = raw*lsb (uV) / (1000 << shift) */
195 			*val = chip->config->bus_voltage_lsb;
196 			*val2 = 1000 << chip->config->bus_voltage_shift;
197 			return IIO_VAL_FRACTIONAL;
198 
199 		case INA2XX_POWER:
200 			/* processed (mW) = raw*lsb (uW) / 1000 */
201 			*val = chip->config->power_lsb;
202 			*val2 = 1000;
203 			return IIO_VAL_FRACTIONAL;
204 
205 		case INA2XX_CURRENT:
206 			/* processed (mA) = raw (mA) */
207 			*val = 1;
208 			return IIO_VAL_INT;
209 		}
210 	}
211 
212 	return -EINVAL;
213 }
214 
215 /*
216  * Available averaging rates for ina226. The indices correspond with
217  * the bit values expected by the chip (according to the ina226 datasheet,
218  * table 3 AVG bit settings, found at
219  * http://www.ti.com/lit/ds/symlink/ina226.pdf.
220  */
221 static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
222 
223 static int ina226_set_average(struct ina2xx_chip_info *chip, unsigned int val,
224 			      unsigned int *config)
225 {
226 	int bits;
227 
228 	if (val > 1024 || val < 1)
229 		return -EINVAL;
230 
231 	bits = find_closest(val, ina226_avg_tab,
232 			    ARRAY_SIZE(ina226_avg_tab));
233 
234 	chip->avg = ina226_avg_tab[bits];
235 
236 	*config &= ~INA226_AVG_MASK;
237 	*config |= INA226_SHIFT_AVG(bits) & INA226_AVG_MASK;
238 
239 	return 0;
240 }
241 
242 /* Conversion times in uS */
243 static const int ina226_conv_time_tab[] = { 140, 204, 332, 588, 1100,
244 					    2116, 4156, 8244 };
245 
246 static int ina226_set_int_time_vbus(struct ina2xx_chip_info *chip,
247 				    unsigned int val_us, unsigned int *config)
248 {
249 	int bits;
250 
251 	if (val_us > 8244 || val_us < 140)
252 		return -EINVAL;
253 
254 	bits = find_closest(val_us, ina226_conv_time_tab,
255 			    ARRAY_SIZE(ina226_conv_time_tab));
256 
257 	chip->int_time_vbus = ina226_conv_time_tab[bits];
258 
259 	*config &= ~INA226_ITB_MASK;
260 	*config |= INA226_SHIFT_ITB(bits) & INA226_ITB_MASK;
261 
262 	return 0;
263 }
264 
265 static int ina226_set_int_time_vshunt(struct ina2xx_chip_info *chip,
266 				      unsigned int val_us, unsigned int *config)
267 {
268 	int bits;
269 
270 	if (val_us > 8244 || val_us < 140)
271 		return -EINVAL;
272 
273 	bits = find_closest(val_us, ina226_conv_time_tab,
274 			    ARRAY_SIZE(ina226_conv_time_tab));
275 
276 	chip->int_time_vshunt = ina226_conv_time_tab[bits];
277 
278 	*config &= ~INA226_ITS_MASK;
279 	*config |= INA226_SHIFT_ITS(bits) & INA226_ITS_MASK;
280 
281 	return 0;
282 }
283 
284 static int ina2xx_write_raw(struct iio_dev *indio_dev,
285 			    struct iio_chan_spec const *chan,
286 			    int val, int val2, long mask)
287 {
288 	struct ina2xx_chip_info *chip = iio_priv(indio_dev);
289 	unsigned int config, tmp;
290 	int ret;
291 
292 	if (iio_buffer_enabled(indio_dev))
293 		return -EBUSY;
294 
295 	mutex_lock(&chip->state_lock);
296 
297 	ret = regmap_read(chip->regmap, INA2XX_CONFIG, &config);
298 	if (ret)
299 		goto err;
300 
301 	tmp = config;
302 
303 	switch (mask) {
304 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
305 		ret = ina226_set_average(chip, val, &tmp);
306 		break;
307 
308 	case IIO_CHAN_INFO_INT_TIME:
309 		if (chan->address == INA2XX_SHUNT_VOLTAGE)
310 			ret = ina226_set_int_time_vshunt(chip, val2, &tmp);
311 		else
312 			ret = ina226_set_int_time_vbus(chip, val2, &tmp);
313 		break;
314 
315 	default:
316 		ret = -EINVAL;
317 	}
318 
319 	if (!ret && (tmp != config))
320 		ret = regmap_write(chip->regmap, INA2XX_CONFIG, tmp);
321 err:
322 	mutex_unlock(&chip->state_lock);
323 
324 	return ret;
325 }
326 
327 static ssize_t ina2xx_allow_async_readout_show(struct device *dev,
328 					   struct device_attribute *attr,
329 					   char *buf)
330 {
331 	struct ina2xx_chip_info *chip = iio_priv(dev_to_iio_dev(dev));
332 
333 	return sprintf(buf, "%d\n", chip->allow_async_readout);
334 }
335 
336 static ssize_t ina2xx_allow_async_readout_store(struct device *dev,
337 				struct device_attribute *attr,
338 				const char *buf, size_t len)
339 {
340 	struct ina2xx_chip_info *chip = iio_priv(dev_to_iio_dev(dev));
341 	bool val;
342 	int ret;
343 
344 	ret = strtobool((const char *) buf, &val);
345 	if (ret)
346 		return ret;
347 
348 	chip->allow_async_readout = val;
349 
350 	return len;
351 }
352 
353 static int set_shunt_resistor(struct ina2xx_chip_info *chip, unsigned int val)
354 {
355 	if (val <= 0 || val > chip->config->calibration_factor)
356 		return -EINVAL;
357 
358 	chip->shunt_resistor = val;
359 
360 	return 0;
361 }
362 
363 static ssize_t ina2xx_shunt_resistor_show(struct device *dev,
364 					  struct device_attribute *attr,
365 					  char *buf)
366 {
367 	struct ina2xx_chip_info *chip = iio_priv(dev_to_iio_dev(dev));
368 
369 	return sprintf(buf, "%d\n", chip->shunt_resistor);
370 }
371 
372 static ssize_t ina2xx_shunt_resistor_store(struct device *dev,
373 					   struct device_attribute *attr,
374 					   const char *buf, size_t len)
375 {
376 	struct ina2xx_chip_info *chip = iio_priv(dev_to_iio_dev(dev));
377 	unsigned long val;
378 	int ret;
379 
380 	ret = kstrtoul((const char *) buf, 10, &val);
381 	if (ret)
382 		return ret;
383 
384 	ret = set_shunt_resistor(chip, val);
385 	if (ret)
386 		return ret;
387 
388 	return len;
389 }
390 
391 #define INA2XX_CHAN(_type, _index, _address) { \
392 	.type = (_type), \
393 	.address = (_address), \
394 	.indexed = 1, \
395 	.channel = (_index), \
396 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \
397 	| BIT(IIO_CHAN_INFO_SCALE), \
398 	.info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
399 				   BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
400 	.scan_index = (_index), \
401 	.scan_type = { \
402 		.sign = 'u', \
403 		.realbits = 16, \
404 		.storagebits = 16, \
405 		.endianness = IIO_CPU, \
406 	} \
407 }
408 
409 /*
410  * Sampling Freq is a consequence of the integration times of
411  * the Voltage channels.
412  */
413 #define INA2XX_CHAN_VOLTAGE(_index, _address) { \
414 	.type = IIO_VOLTAGE, \
415 	.address = (_address), \
416 	.indexed = 1, \
417 	.channel = (_index), \
418 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
419 			      BIT(IIO_CHAN_INFO_SCALE) | \
420 			      BIT(IIO_CHAN_INFO_INT_TIME), \
421 	.scan_index = (_index), \
422 	.scan_type = { \
423 		.sign = 'u', \
424 		.realbits = 16, \
425 		.storagebits = 16, \
426 		.endianness = IIO_LE, \
427 	} \
428 }
429 
430 static const struct iio_chan_spec ina2xx_channels[] = {
431 	INA2XX_CHAN_VOLTAGE(0, INA2XX_SHUNT_VOLTAGE),
432 	INA2XX_CHAN_VOLTAGE(1, INA2XX_BUS_VOLTAGE),
433 	INA2XX_CHAN(IIO_POWER, 2, INA2XX_POWER),
434 	INA2XX_CHAN(IIO_CURRENT, 3, INA2XX_CURRENT),
435 	IIO_CHAN_SOFT_TIMESTAMP(4),
436 };
437 
438 static int ina2xx_work_buffer(struct iio_dev *indio_dev)
439 {
440 	struct ina2xx_chip_info *chip = iio_priv(indio_dev);
441 	unsigned short data[8];
442 	int bit, ret, i = 0;
443 	s64 time_a, time_b;
444 	unsigned int alert;
445 
446 	time_a = iio_get_time_ns();
447 
448 	/*
449 	 * Because the timer thread and the chip conversion clock
450 	 * are asynchronous, the period difference will eventually
451 	 * result in reading V[k-1] again, or skip V[k] at time Tk.
452 	 * In order to resync the timer with the conversion process
453 	 * we check the ConVersionReadyFlag.
454 	 * On hardware that supports using the ALERT pin to toggle a
455 	 * GPIO a triggered buffer could be used instead.
456 	 * For now, we pay for that extra read of the ALERT register
457 	 */
458 	if (!chip->allow_async_readout)
459 		do {
460 			ret = regmap_read(chip->regmap, INA226_ALERT_MASK,
461 					  &alert);
462 			if (ret < 0)
463 				return ret;
464 
465 			alert &= INA266_CVRF;
466 		} while (!alert);
467 
468 	/*
469 	 * Single register reads: bulk_read will not work with ina226
470 	 * as there is no auto-increment of the address register for
471 	 * data length longer than 16bits.
472 	 */
473 	for_each_set_bit(bit, indio_dev->active_scan_mask,
474 			 indio_dev->masklength) {
475 		unsigned int val;
476 
477 		ret = regmap_read(chip->regmap,
478 				  INA2XX_SHUNT_VOLTAGE + bit, &val);
479 		if (ret < 0)
480 			return ret;
481 
482 		data[i++] = val;
483 	}
484 
485 	time_b = iio_get_time_ns();
486 
487 	iio_push_to_buffers_with_timestamp(indio_dev,
488 					   (unsigned int *)data, time_a);
489 
490 	chip->prev_ns = time_a;
491 
492 	return (unsigned long)(time_b - time_a) / 1000;
493 };
494 
495 static int ina2xx_capture_thread(void *data)
496 {
497 	struct iio_dev *indio_dev = data;
498 	struct ina2xx_chip_info *chip = iio_priv(indio_dev);
499 	unsigned int sampling_us = SAMPLING_PERIOD(chip);
500 	int buffer_us;
501 
502 	/*
503 	 * Poll a bit faster than the chip internal Fs, in case
504 	 * we wish to sync with the conversion ready flag.
505 	 */
506 	if (!chip->allow_async_readout)
507 		sampling_us -= 200;
508 
509 	do {
510 		buffer_us = ina2xx_work_buffer(indio_dev);
511 		if (buffer_us < 0)
512 			return buffer_us;
513 
514 		if (sampling_us > buffer_us)
515 			udelay(sampling_us - buffer_us);
516 
517 	} while (!kthread_should_stop());
518 
519 	return 0;
520 }
521 
522 static int ina2xx_buffer_enable(struct iio_dev *indio_dev)
523 {
524 	struct ina2xx_chip_info *chip = iio_priv(indio_dev);
525 	unsigned int sampling_us = SAMPLING_PERIOD(chip);
526 
527 	dev_dbg(&indio_dev->dev, "Enabling buffer w/ scan_mask %02x, freq = %d, avg =%u\n",
528 		(unsigned int)(*indio_dev->active_scan_mask),
529 		1000000 / sampling_us, chip->avg);
530 
531 	dev_dbg(&indio_dev->dev, "Expected work period: %u us\n", sampling_us);
532 	dev_dbg(&indio_dev->dev, "Async readout mode: %d\n",
533 		chip->allow_async_readout);
534 
535 	chip->prev_ns = iio_get_time_ns();
536 
537 	chip->task = kthread_run(ina2xx_capture_thread, (void *)indio_dev,
538 				 "%s:%d-%uus", indio_dev->name, indio_dev->id,
539 				 sampling_us);
540 
541 	return PTR_ERR_OR_ZERO(chip->task);
542 }
543 
544 static int ina2xx_buffer_disable(struct iio_dev *indio_dev)
545 {
546 	struct ina2xx_chip_info *chip = iio_priv(indio_dev);
547 
548 	if (chip->task) {
549 		kthread_stop(chip->task);
550 		chip->task = NULL;
551 	}
552 
553 	return 0;
554 }
555 
556 static const struct iio_buffer_setup_ops ina2xx_setup_ops = {
557 	.postenable = &ina2xx_buffer_enable,
558 	.predisable = &ina2xx_buffer_disable,
559 };
560 
561 static int ina2xx_debug_reg(struct iio_dev *indio_dev,
562 			    unsigned reg, unsigned writeval, unsigned *readval)
563 {
564 	struct ina2xx_chip_info *chip = iio_priv(indio_dev);
565 
566 	if (!readval)
567 		return regmap_write(chip->regmap, reg, writeval);
568 
569 	return regmap_read(chip->regmap, reg, readval);
570 }
571 
572 /* Possible integration times for vshunt and vbus */
573 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.000140 0.000204 0.000332 0.000588 0.001100 0.002116 0.004156 0.008244");
574 
575 static IIO_DEVICE_ATTR(in_allow_async_readout, S_IRUGO | S_IWUSR,
576 		       ina2xx_allow_async_readout_show,
577 		       ina2xx_allow_async_readout_store, 0);
578 
579 static IIO_DEVICE_ATTR(in_shunt_resistor, S_IRUGO | S_IWUSR,
580 		       ina2xx_shunt_resistor_show,
581 		       ina2xx_shunt_resistor_store, 0);
582 
583 static struct attribute *ina2xx_attributes[] = {
584 	&iio_dev_attr_in_allow_async_readout.dev_attr.attr,
585 	&iio_const_attr_integration_time_available.dev_attr.attr,
586 	&iio_dev_attr_in_shunt_resistor.dev_attr.attr,
587 	NULL,
588 };
589 
590 static const struct attribute_group ina2xx_attribute_group = {
591 	.attrs = ina2xx_attributes,
592 };
593 
594 static const struct iio_info ina2xx_info = {
595 	.driver_module = THIS_MODULE,
596 	.attrs = &ina2xx_attribute_group,
597 	.read_raw = ina2xx_read_raw,
598 	.write_raw = ina2xx_write_raw,
599 	.debugfs_reg_access = ina2xx_debug_reg,
600 };
601 
602 /* Initialize the configuration and calibration registers. */
603 static int ina2xx_init(struct ina2xx_chip_info *chip, unsigned int config)
604 {
605 	u16 regval;
606 	int ret;
607 
608 	ret = regmap_write(chip->regmap, INA2XX_CONFIG, config);
609 	if (ret)
610 		return ret;
611 
612 	/*
613 	 * Set current LSB to 1mA, shunt is in uOhms
614 	 * (equation 13 in datasheet). We hardcode a Current_LSB
615 	 * of 1.0 x10-6. The only remaining parameter is RShunt.
616 	 * There is no need to expose the CALIBRATION register
617 	 * to the user for now.
618 	 */
619 	regval = DIV_ROUND_CLOSEST(chip->config->calibration_factor,
620 				   chip->shunt_resistor);
621 
622 	return regmap_write(chip->regmap, INA2XX_CALIBRATION, regval);
623 }
624 
625 static int ina2xx_probe(struct i2c_client *client,
626 			const struct i2c_device_id *id)
627 {
628 	struct ina2xx_chip_info *chip;
629 	struct iio_dev *indio_dev;
630 	struct iio_buffer *buffer;
631 	unsigned int val;
632 	int ret;
633 
634 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
635 	if (!indio_dev)
636 		return -ENOMEM;
637 
638 	chip = iio_priv(indio_dev);
639 
640 	/* This is only used for device removal purposes. */
641 	i2c_set_clientdata(client, indio_dev);
642 
643 	chip->regmap = devm_regmap_init_i2c(client, &ina2xx_regmap_config);
644 	if (IS_ERR(chip->regmap)) {
645 		dev_err(&client->dev, "failed to allocate register map\n");
646 		return PTR_ERR(chip->regmap);
647 	}
648 
649 	chip->config = &ina2xx_config[id->driver_data];
650 
651 	mutex_init(&chip->state_lock);
652 
653 	if (of_property_read_u32(client->dev.of_node,
654 				 "shunt-resistor", &val) < 0) {
655 		struct ina2xx_platform_data *pdata =
656 		    dev_get_platdata(&client->dev);
657 
658 		if (pdata)
659 			val = pdata->shunt_uohms;
660 		else
661 			val = INA2XX_RSHUNT_DEFAULT;
662 	}
663 
664 	ret = set_shunt_resistor(chip, val);
665 	if (ret)
666 		return ret;
667 
668 	/* Patch the current config register with default. */
669 	val = chip->config->config_default;
670 
671 	if (id->driver_data == ina226) {
672 		ina226_set_average(chip, INA226_DEFAULT_AVG, &val);
673 		ina226_set_int_time_vbus(chip, INA226_DEFAULT_IT, &val);
674 		ina226_set_int_time_vshunt(chip, INA226_DEFAULT_IT, &val);
675 	}
676 
677 	ret = ina2xx_init(chip, val);
678 	if (ret) {
679 		dev_err(&client->dev, "error configuring the device\n");
680 		return ret;
681 	}
682 
683 	indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
684 	indio_dev->dev.parent = &client->dev;
685 	indio_dev->channels = ina2xx_channels;
686 	indio_dev->num_channels = ARRAY_SIZE(ina2xx_channels);
687 	indio_dev->name = id->name;
688 	indio_dev->info = &ina2xx_info;
689 	indio_dev->setup_ops = &ina2xx_setup_ops;
690 
691 	buffer = devm_iio_kfifo_allocate(&indio_dev->dev);
692 	if (!buffer)
693 		return -ENOMEM;
694 
695 	iio_device_attach_buffer(indio_dev, buffer);
696 
697 	return iio_device_register(indio_dev);
698 }
699 
700 static int ina2xx_remove(struct i2c_client *client)
701 {
702 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
703 	struct ina2xx_chip_info *chip = iio_priv(indio_dev);
704 
705 	iio_device_unregister(indio_dev);
706 
707 	/* Powerdown */
708 	return regmap_update_bits(chip->regmap, INA2XX_CONFIG,
709 				  INA2XX_MODE_MASK, 0);
710 }
711 
712 static const struct i2c_device_id ina2xx_id[] = {
713 	{"ina219", ina219},
714 	{"ina220", ina219},
715 	{"ina226", ina226},
716 	{"ina230", ina226},
717 	{"ina231", ina226},
718 	{}
719 };
720 MODULE_DEVICE_TABLE(i2c, ina2xx_id);
721 
722 static struct i2c_driver ina2xx_driver = {
723 	.driver = {
724 		   .name = KBUILD_MODNAME,
725 	},
726 	.probe = ina2xx_probe,
727 	.remove = ina2xx_remove,
728 	.id_table = ina2xx_id,
729 };
730 module_i2c_driver(ina2xx_driver);
731 
732 MODULE_AUTHOR("Marc Titinger <marc.titinger@baylibre.com>");
733 MODULE_DESCRIPTION("Texas Instruments INA2XX ADC driver");
734 MODULE_LICENSE("GPL v2");
735