xref: /openbmc/linux/drivers/hwmon/ina2xx.c (revision 3e8bd1ba)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for Texas Instruments INA219, INA226 power monitor chips
4  *
5  * INA219:
6  * Zero Drift Bi-Directional Current/Power Monitor with I2C Interface
7  * Datasheet: https://www.ti.com/product/ina219
8  *
9  * INA220:
10  * Bi-Directional Current/Power Monitor with I2C Interface
11  * Datasheet: https://www.ti.com/product/ina220
12  *
13  * INA226:
14  * Bi-Directional Current/Power Monitor with I2C Interface
15  * Datasheet: https://www.ti.com/product/ina226
16  *
17  * INA230:
18  * Bi-directional Current/Power Monitor with I2C Interface
19  * Datasheet: https://www.ti.com/product/ina230
20  *
21  * Copyright (C) 2012 Lothar Felten <lothar.felten@gmail.com>
22  * Thanks to Jan Volkering
23  */
24 
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/err.h>
29 #include <linux/slab.h>
30 #include <linux/i2c.h>
31 #include <linux/hwmon.h>
32 #include <linux/hwmon-sysfs.h>
33 #include <linux/jiffies.h>
34 #include <linux/of.h>
35 #include <linux/delay.h>
36 #include <linux/util_macros.h>
37 #include <linux/regmap.h>
38 
39 #include <linux/platform_data/ina2xx.h>
40 
41 /* common register definitions */
42 #define INA2XX_CONFIG			0x00
43 #define INA2XX_SHUNT_VOLTAGE		0x01 /* readonly */
44 #define INA2XX_BUS_VOLTAGE		0x02 /* readonly */
45 #define INA2XX_POWER			0x03 /* readonly */
46 #define INA2XX_CURRENT			0x04 /* readonly */
47 #define INA2XX_CALIBRATION		0x05
48 
49 /* INA226 register definitions */
50 #define INA226_MASK_ENABLE		0x06
51 #define INA226_ALERT_LIMIT		0x07
52 #define INA226_DIE_ID			0xFF
53 
54 /* register count */
55 #define INA219_REGISTERS		6
56 #define INA226_REGISTERS		8
57 
58 #define INA2XX_MAX_REGISTERS		8
59 
60 /* settings - depend on use case */
61 #define INA219_CONFIG_DEFAULT		0x399F	/* PGA=8 */
62 #define INA226_CONFIG_DEFAULT		0x4527	/* averages=16 */
63 
64 /* worst case is 68.10 ms (~14.6Hz, ina219) */
65 #define INA2XX_CONVERSION_RATE		15
66 #define INA2XX_MAX_DELAY		69 /* worst case delay in ms */
67 
68 #define INA2XX_RSHUNT_DEFAULT		10000
69 
70 /* bit mask for reading the averaging setting in the configuration register */
71 #define INA226_AVG_RD_MASK		0x0E00
72 
73 #define INA226_READ_AVG(reg)		(((reg) & INA226_AVG_RD_MASK) >> 9)
74 #define INA226_SHIFT_AVG(val)		((val) << 9)
75 
76 /* bit number of alert functions in Mask/Enable Register */
77 #define INA226_SHUNT_OVER_VOLTAGE_BIT	15
78 #define INA226_SHUNT_UNDER_VOLTAGE_BIT	14
79 #define INA226_BUS_OVER_VOLTAGE_BIT	13
80 #define INA226_BUS_UNDER_VOLTAGE_BIT	12
81 #define INA226_POWER_OVER_LIMIT_BIT	11
82 
83 /* bit mask for alert config bits of Mask/Enable Register */
84 #define INA226_ALERT_CONFIG_MASK	0xFC00
85 #define INA226_ALERT_FUNCTION_FLAG	BIT(4)
86 
87 /* common attrs, ina226 attrs and NULL */
88 #define INA2XX_MAX_ATTRIBUTE_GROUPS	3
89 
90 /*
91  * Both bus voltage and shunt voltage conversion times for ina226 are set
92  * to 0b0100 on POR, which translates to 2200 microseconds in total.
93  */
94 #define INA226_TOTAL_CONV_TIME_DEFAULT	2200
95 
96 static struct regmap_config ina2xx_regmap_config = {
97 	.reg_bits = 8,
98 	.val_bits = 16,
99 };
100 
101 enum ina2xx_ids { ina219, ina226 };
102 
103 struct ina2xx_config {
104 	u16 config_default;
105 	int calibration_value;
106 	int registers;
107 	int shunt_div;
108 	int bus_voltage_shift;
109 	int bus_voltage_lsb;	/* uV */
110 	int power_lsb_factor;
111 };
112 
113 struct ina2xx_data {
114 	const struct ina2xx_config *config;
115 
116 	long rshunt;
117 	long current_lsb_uA;
118 	long power_lsb_uW;
119 	struct mutex config_lock;
120 	struct regmap *regmap;
121 
122 	const struct attribute_group *groups[INA2XX_MAX_ATTRIBUTE_GROUPS];
123 };
124 
125 static const struct ina2xx_config ina2xx_config[] = {
126 	[ina219] = {
127 		.config_default = INA219_CONFIG_DEFAULT,
128 		.calibration_value = 4096,
129 		.registers = INA219_REGISTERS,
130 		.shunt_div = 100,
131 		.bus_voltage_shift = 3,
132 		.bus_voltage_lsb = 4000,
133 		.power_lsb_factor = 20,
134 	},
135 	[ina226] = {
136 		.config_default = INA226_CONFIG_DEFAULT,
137 		.calibration_value = 2048,
138 		.registers = INA226_REGISTERS,
139 		.shunt_div = 400,
140 		.bus_voltage_shift = 0,
141 		.bus_voltage_lsb = 1250,
142 		.power_lsb_factor = 25,
143 	},
144 };
145 
146 /*
147  * Available averaging rates for ina226. The indices correspond with
148  * the bit values expected by the chip (according to the ina226 datasheet,
149  * table 3 AVG bit settings, found at
150  * https://www.ti.com/lit/ds/symlink/ina226.pdf.
151  */
152 static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
153 
154 static int ina226_reg_to_interval(u16 config)
155 {
156 	int avg = ina226_avg_tab[INA226_READ_AVG(config)];
157 
158 	/*
159 	 * Multiply the total conversion time by the number of averages.
160 	 * Return the result in milliseconds.
161 	 */
162 	return DIV_ROUND_CLOSEST(avg * INA226_TOTAL_CONV_TIME_DEFAULT, 1000);
163 }
164 
165 /*
166  * Return the new, shifted AVG field value of CONFIG register,
167  * to use with regmap_update_bits
168  */
169 static u16 ina226_interval_to_reg(int interval)
170 {
171 	int avg, avg_bits;
172 
173 	avg = DIV_ROUND_CLOSEST(interval * 1000,
174 				INA226_TOTAL_CONV_TIME_DEFAULT);
175 	avg_bits = find_closest(avg, ina226_avg_tab,
176 				ARRAY_SIZE(ina226_avg_tab));
177 
178 	return INA226_SHIFT_AVG(avg_bits);
179 }
180 
181 /*
182  * Calibration register is set to the best value, which eliminates
183  * truncation errors on calculating current register in hardware.
184  * According to datasheet (eq. 3) the best values are 2048 for
185  * ina226 and 4096 for ina219. They are hardcoded as calibration_value.
186  */
187 static int ina2xx_calibrate(struct ina2xx_data *data)
188 {
189 	return regmap_write(data->regmap, INA2XX_CALIBRATION,
190 			    data->config->calibration_value);
191 }
192 
193 /*
194  * Initialize the configuration and calibration registers.
195  */
196 static int ina2xx_init(struct ina2xx_data *data)
197 {
198 	int ret = regmap_write(data->regmap, INA2XX_CONFIG,
199 			       data->config->config_default);
200 	if (ret < 0)
201 		return ret;
202 
203 	return ina2xx_calibrate(data);
204 }
205 
206 static int ina2xx_read_reg(struct device *dev, int reg, unsigned int *regval)
207 {
208 	struct ina2xx_data *data = dev_get_drvdata(dev);
209 	int ret, retry;
210 
211 	dev_dbg(dev, "Starting register %d read\n", reg);
212 
213 	for (retry = 5; retry; retry--) {
214 
215 		ret = regmap_read(data->regmap, reg, regval);
216 		if (ret < 0)
217 			return ret;
218 
219 		dev_dbg(dev, "read %d, val = 0x%04x\n", reg, *regval);
220 
221 		/*
222 		 * If the current value in the calibration register is 0, the
223 		 * power and current registers will also remain at 0. In case
224 		 * the chip has been reset let's check the calibration
225 		 * register and reinitialize if needed.
226 		 * We do that extra read of the calibration register if there
227 		 * is some hint of a chip reset.
228 		 */
229 		if (*regval == 0) {
230 			unsigned int cal;
231 
232 			ret = regmap_read(data->regmap, INA2XX_CALIBRATION,
233 					  &cal);
234 			if (ret < 0)
235 				return ret;
236 
237 			if (cal == 0) {
238 				dev_warn(dev, "chip not calibrated, reinitializing\n");
239 
240 				ret = ina2xx_init(data);
241 				if (ret < 0)
242 					return ret;
243 				/*
244 				 * Let's make sure the power and current
245 				 * registers have been updated before trying
246 				 * again.
247 				 */
248 				msleep(INA2XX_MAX_DELAY);
249 				continue;
250 			}
251 		}
252 		return 0;
253 	}
254 
255 	/*
256 	 * If we're here then although all write operations succeeded, the
257 	 * chip still returns 0 in the calibration register. Nothing more we
258 	 * can do here.
259 	 */
260 	dev_err(dev, "unable to reinitialize the chip\n");
261 	return -ENODEV;
262 }
263 
264 static int ina2xx_get_value(struct ina2xx_data *data, u8 reg,
265 			    unsigned int regval)
266 {
267 	int val;
268 
269 	switch (reg) {
270 	case INA2XX_SHUNT_VOLTAGE:
271 		/* signed register */
272 		val = DIV_ROUND_CLOSEST((s16)regval, data->config->shunt_div);
273 		break;
274 	case INA2XX_BUS_VOLTAGE:
275 		val = (regval >> data->config->bus_voltage_shift)
276 		  * data->config->bus_voltage_lsb;
277 		val = DIV_ROUND_CLOSEST(val, 1000);
278 		break;
279 	case INA2XX_POWER:
280 		val = regval * data->power_lsb_uW;
281 		break;
282 	case INA2XX_CURRENT:
283 		/* signed register, result in mA */
284 		val = (s16)regval * data->current_lsb_uA;
285 		val = DIV_ROUND_CLOSEST(val, 1000);
286 		break;
287 	case INA2XX_CALIBRATION:
288 		val = regval;
289 		break;
290 	default:
291 		/* programmer goofed */
292 		WARN_ON_ONCE(1);
293 		val = 0;
294 		break;
295 	}
296 
297 	return val;
298 }
299 
300 static ssize_t ina2xx_value_show(struct device *dev,
301 				 struct device_attribute *da, char *buf)
302 {
303 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
304 	struct ina2xx_data *data = dev_get_drvdata(dev);
305 	unsigned int regval;
306 
307 	int err = ina2xx_read_reg(dev, attr->index, &regval);
308 
309 	if (err < 0)
310 		return err;
311 
312 	return sysfs_emit(buf, "%d\n", ina2xx_get_value(data, attr->index, regval));
313 }
314 
315 static int ina226_reg_to_alert(struct ina2xx_data *data, u8 bit, u16 regval)
316 {
317 	int reg;
318 
319 	switch (bit) {
320 	case INA226_SHUNT_OVER_VOLTAGE_BIT:
321 	case INA226_SHUNT_UNDER_VOLTAGE_BIT:
322 		reg = INA2XX_SHUNT_VOLTAGE;
323 		break;
324 	case INA226_BUS_OVER_VOLTAGE_BIT:
325 	case INA226_BUS_UNDER_VOLTAGE_BIT:
326 		reg = INA2XX_BUS_VOLTAGE;
327 		break;
328 	case INA226_POWER_OVER_LIMIT_BIT:
329 		reg = INA2XX_POWER;
330 		break;
331 	default:
332 		/* programmer goofed */
333 		WARN_ON_ONCE(1);
334 		return 0;
335 	}
336 
337 	return ina2xx_get_value(data, reg, regval);
338 }
339 
340 /*
341  * Turns alert limit values into register values.
342  * Opposite of the formula in ina2xx_get_value().
343  */
344 static s16 ina226_alert_to_reg(struct ina2xx_data *data, u8 bit, int val)
345 {
346 	switch (bit) {
347 	case INA226_SHUNT_OVER_VOLTAGE_BIT:
348 	case INA226_SHUNT_UNDER_VOLTAGE_BIT:
349 		val *= data->config->shunt_div;
350 		return clamp_val(val, SHRT_MIN, SHRT_MAX);
351 	case INA226_BUS_OVER_VOLTAGE_BIT:
352 	case INA226_BUS_UNDER_VOLTAGE_BIT:
353 		val = (val * 1000) << data->config->bus_voltage_shift;
354 		val = DIV_ROUND_CLOSEST(val, data->config->bus_voltage_lsb);
355 		return clamp_val(val, 0, SHRT_MAX);
356 	case INA226_POWER_OVER_LIMIT_BIT:
357 		val = DIV_ROUND_CLOSEST(val, data->power_lsb_uW);
358 		return clamp_val(val, 0, USHRT_MAX);
359 	default:
360 		/* programmer goofed */
361 		WARN_ON_ONCE(1);
362 		return 0;
363 	}
364 }
365 
366 static ssize_t ina226_alert_show(struct device *dev,
367 				 struct device_attribute *da, char *buf)
368 {
369 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
370 	struct ina2xx_data *data = dev_get_drvdata(dev);
371 	int regval;
372 	int val = 0;
373 	int ret;
374 
375 	mutex_lock(&data->config_lock);
376 	ret = regmap_read(data->regmap, INA226_MASK_ENABLE, &regval);
377 	if (ret)
378 		goto abort;
379 
380 	if (regval & BIT(attr->index)) {
381 		ret = regmap_read(data->regmap, INA226_ALERT_LIMIT, &regval);
382 		if (ret)
383 			goto abort;
384 		val = ina226_reg_to_alert(data, attr->index, regval);
385 	}
386 
387 	ret = sysfs_emit(buf, "%d\n", val);
388 abort:
389 	mutex_unlock(&data->config_lock);
390 	return ret;
391 }
392 
393 static ssize_t ina226_alert_store(struct device *dev,
394 				  struct device_attribute *da,
395 				  const char *buf, size_t count)
396 {
397 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
398 	struct ina2xx_data *data = dev_get_drvdata(dev);
399 	unsigned long val;
400 	int ret;
401 
402 	ret = kstrtoul(buf, 10, &val);
403 	if (ret < 0)
404 		return ret;
405 
406 	/*
407 	 * Clear all alerts first to avoid accidentally triggering ALERT pin
408 	 * due to register write sequence. Then, only enable the alert
409 	 * if the value is non-zero.
410 	 */
411 	mutex_lock(&data->config_lock);
412 	ret = regmap_update_bits(data->regmap, INA226_MASK_ENABLE,
413 				 INA226_ALERT_CONFIG_MASK, 0);
414 	if (ret < 0)
415 		goto abort;
416 
417 	ret = regmap_write(data->regmap, INA226_ALERT_LIMIT,
418 			   ina226_alert_to_reg(data, attr->index, val));
419 	if (ret < 0)
420 		goto abort;
421 
422 	if (val != 0) {
423 		ret = regmap_update_bits(data->regmap, INA226_MASK_ENABLE,
424 					 INA226_ALERT_CONFIG_MASK,
425 					 BIT(attr->index));
426 		if (ret < 0)
427 			goto abort;
428 	}
429 
430 	ret = count;
431 abort:
432 	mutex_unlock(&data->config_lock);
433 	return ret;
434 }
435 
436 static ssize_t ina226_alarm_show(struct device *dev,
437 				 struct device_attribute *da, char *buf)
438 {
439 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
440 	struct ina2xx_data *data = dev_get_drvdata(dev);
441 	int regval;
442 	int alarm = 0;
443 	int ret;
444 
445 	ret = regmap_read(data->regmap, INA226_MASK_ENABLE, &regval);
446 	if (ret)
447 		return ret;
448 
449 	alarm = (regval & BIT(attr->index)) &&
450 		(regval & INA226_ALERT_FUNCTION_FLAG);
451 	return sysfs_emit(buf, "%d\n", alarm);
452 }
453 
454 /*
455  * In order to keep calibration register value fixed, the product
456  * of current_lsb and shunt_resistor should also be fixed and equal
457  * to shunt_voltage_lsb = 1 / shunt_div multiplied by 10^9 in order
458  * to keep the scale.
459  */
460 static int ina2xx_set_shunt(struct ina2xx_data *data, long val)
461 {
462 	unsigned int dividend = DIV_ROUND_CLOSEST(1000000000,
463 						  data->config->shunt_div);
464 	if (val <= 0 || val > dividend)
465 		return -EINVAL;
466 
467 	mutex_lock(&data->config_lock);
468 	data->rshunt = val;
469 	data->current_lsb_uA = DIV_ROUND_CLOSEST(dividend, val);
470 	data->power_lsb_uW = data->config->power_lsb_factor *
471 			     data->current_lsb_uA;
472 	mutex_unlock(&data->config_lock);
473 
474 	return 0;
475 }
476 
477 static ssize_t ina2xx_shunt_show(struct device *dev,
478 				 struct device_attribute *da, char *buf)
479 {
480 	struct ina2xx_data *data = dev_get_drvdata(dev);
481 
482 	return sysfs_emit(buf, "%li\n", data->rshunt);
483 }
484 
485 static ssize_t ina2xx_shunt_store(struct device *dev,
486 				  struct device_attribute *da,
487 				  const char *buf, size_t count)
488 {
489 	unsigned long val;
490 	int status;
491 	struct ina2xx_data *data = dev_get_drvdata(dev);
492 
493 	status = kstrtoul(buf, 10, &val);
494 	if (status < 0)
495 		return status;
496 
497 	status = ina2xx_set_shunt(data, val);
498 	if (status < 0)
499 		return status;
500 	return count;
501 }
502 
503 static ssize_t ina226_interval_store(struct device *dev,
504 				     struct device_attribute *da,
505 				     const char *buf, size_t count)
506 {
507 	struct ina2xx_data *data = dev_get_drvdata(dev);
508 	unsigned long val;
509 	int status;
510 
511 	status = kstrtoul(buf, 10, &val);
512 	if (status < 0)
513 		return status;
514 
515 	if (val > INT_MAX || val == 0)
516 		return -EINVAL;
517 
518 	status = regmap_update_bits(data->regmap, INA2XX_CONFIG,
519 				    INA226_AVG_RD_MASK,
520 				    ina226_interval_to_reg(val));
521 	if (status < 0)
522 		return status;
523 
524 	return count;
525 }
526 
527 static ssize_t ina226_interval_show(struct device *dev,
528 				    struct device_attribute *da, char *buf)
529 {
530 	struct ina2xx_data *data = dev_get_drvdata(dev);
531 	int status;
532 	unsigned int regval;
533 
534 	status = regmap_read(data->regmap, INA2XX_CONFIG, &regval);
535 	if (status)
536 		return status;
537 
538 	return sysfs_emit(buf, "%d\n", ina226_reg_to_interval(regval));
539 }
540 
541 /* shunt voltage */
542 static SENSOR_DEVICE_ATTR_RO(in0_input, ina2xx_value, INA2XX_SHUNT_VOLTAGE);
543 /* shunt voltage over/under voltage alert setting and alarm */
544 static SENSOR_DEVICE_ATTR_RW(in0_crit, ina226_alert,
545 			     INA226_SHUNT_OVER_VOLTAGE_BIT);
546 static SENSOR_DEVICE_ATTR_RW(in0_lcrit, ina226_alert,
547 			     INA226_SHUNT_UNDER_VOLTAGE_BIT);
548 static SENSOR_DEVICE_ATTR_RO(in0_crit_alarm, ina226_alarm,
549 			     INA226_SHUNT_OVER_VOLTAGE_BIT);
550 static SENSOR_DEVICE_ATTR_RO(in0_lcrit_alarm, ina226_alarm,
551 			     INA226_SHUNT_UNDER_VOLTAGE_BIT);
552 
553 /* bus voltage */
554 static SENSOR_DEVICE_ATTR_RO(in1_input, ina2xx_value, INA2XX_BUS_VOLTAGE);
555 /* bus voltage over/under voltage alert setting and alarm */
556 static SENSOR_DEVICE_ATTR_RW(in1_crit, ina226_alert,
557 			     INA226_BUS_OVER_VOLTAGE_BIT);
558 static SENSOR_DEVICE_ATTR_RW(in1_lcrit, ina226_alert,
559 			     INA226_BUS_UNDER_VOLTAGE_BIT);
560 static SENSOR_DEVICE_ATTR_RO(in1_crit_alarm, ina226_alarm,
561 			     INA226_BUS_OVER_VOLTAGE_BIT);
562 static SENSOR_DEVICE_ATTR_RO(in1_lcrit_alarm, ina226_alarm,
563 			     INA226_BUS_UNDER_VOLTAGE_BIT);
564 
565 /* calculated current */
566 static SENSOR_DEVICE_ATTR_RO(curr1_input, ina2xx_value, INA2XX_CURRENT);
567 
568 /* calculated power */
569 static SENSOR_DEVICE_ATTR_RO(power1_input, ina2xx_value, INA2XX_POWER);
570 /* over-limit power alert setting and alarm */
571 static SENSOR_DEVICE_ATTR_RW(power1_crit, ina226_alert,
572 			     INA226_POWER_OVER_LIMIT_BIT);
573 static SENSOR_DEVICE_ATTR_RO(power1_crit_alarm, ina226_alarm,
574 			     INA226_POWER_OVER_LIMIT_BIT);
575 
576 /* shunt resistance */
577 static SENSOR_DEVICE_ATTR_RW(shunt_resistor, ina2xx_shunt, INA2XX_CALIBRATION);
578 
579 /* update interval (ina226 only) */
580 static SENSOR_DEVICE_ATTR_RW(update_interval, ina226_interval, 0);
581 
582 /* pointers to created device attributes */
583 static struct attribute *ina2xx_attrs[] = {
584 	&sensor_dev_attr_in0_input.dev_attr.attr,
585 	&sensor_dev_attr_in1_input.dev_attr.attr,
586 	&sensor_dev_attr_curr1_input.dev_attr.attr,
587 	&sensor_dev_attr_power1_input.dev_attr.attr,
588 	&sensor_dev_attr_shunt_resistor.dev_attr.attr,
589 	NULL,
590 };
591 
592 static const struct attribute_group ina2xx_group = {
593 	.attrs = ina2xx_attrs,
594 };
595 
596 static struct attribute *ina226_attrs[] = {
597 	&sensor_dev_attr_in0_crit.dev_attr.attr,
598 	&sensor_dev_attr_in0_lcrit.dev_attr.attr,
599 	&sensor_dev_attr_in0_crit_alarm.dev_attr.attr,
600 	&sensor_dev_attr_in0_lcrit_alarm.dev_attr.attr,
601 	&sensor_dev_attr_in1_crit.dev_attr.attr,
602 	&sensor_dev_attr_in1_lcrit.dev_attr.attr,
603 	&sensor_dev_attr_in1_crit_alarm.dev_attr.attr,
604 	&sensor_dev_attr_in1_lcrit_alarm.dev_attr.attr,
605 	&sensor_dev_attr_power1_crit.dev_attr.attr,
606 	&sensor_dev_attr_power1_crit_alarm.dev_attr.attr,
607 	&sensor_dev_attr_update_interval.dev_attr.attr,
608 	NULL,
609 };
610 
611 static const struct attribute_group ina226_group = {
612 	.attrs = ina226_attrs,
613 };
614 
615 static const struct i2c_device_id ina2xx_id[];
616 
617 static int ina2xx_probe(struct i2c_client *client)
618 {
619 	struct device *dev = &client->dev;
620 	struct ina2xx_data *data;
621 	struct device *hwmon_dev;
622 	u32 val;
623 	int ret, group = 0;
624 	enum ina2xx_ids chip;
625 
626 	if (client->dev.of_node)
627 		chip = (uintptr_t)of_device_get_match_data(&client->dev);
628 	else
629 		chip = i2c_match_id(ina2xx_id, client)->driver_data;
630 
631 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
632 	if (!data)
633 		return -ENOMEM;
634 
635 	/* set the device type */
636 	data->config = &ina2xx_config[chip];
637 	mutex_init(&data->config_lock);
638 
639 	if (of_property_read_u32(dev->of_node, "shunt-resistor", &val) < 0) {
640 		struct ina2xx_platform_data *pdata = dev_get_platdata(dev);
641 
642 		if (pdata)
643 			val = pdata->shunt_uohms;
644 		else
645 			val = INA2XX_RSHUNT_DEFAULT;
646 	}
647 
648 	ina2xx_set_shunt(data, val);
649 
650 	ina2xx_regmap_config.max_register = data->config->registers;
651 
652 	data->regmap = devm_regmap_init_i2c(client, &ina2xx_regmap_config);
653 	if (IS_ERR(data->regmap)) {
654 		dev_err(dev, "failed to allocate register map\n");
655 		return PTR_ERR(data->regmap);
656 	}
657 
658 	ret = devm_regulator_get_enable(dev, "vs");
659 	if (ret)
660 		return dev_err_probe(dev, ret, "failed to enable vs regulator\n");
661 
662 	ret = ina2xx_init(data);
663 	if (ret < 0) {
664 		dev_err(dev, "error configuring the device: %d\n", ret);
665 		return -ENODEV;
666 	}
667 
668 	data->groups[group++] = &ina2xx_group;
669 	if (chip == ina226)
670 		data->groups[group++] = &ina226_group;
671 
672 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
673 							   data, data->groups);
674 	if (IS_ERR(hwmon_dev))
675 		return PTR_ERR(hwmon_dev);
676 
677 	dev_info(dev, "power monitor %s (Rshunt = %li uOhm)\n",
678 		 client->name, data->rshunt);
679 
680 	return 0;
681 }
682 
683 static const struct i2c_device_id ina2xx_id[] = {
684 	{ "ina219", ina219 },
685 	{ "ina220", ina219 },
686 	{ "ina226", ina226 },
687 	{ "ina230", ina226 },
688 	{ "ina231", ina226 },
689 	{ }
690 };
691 MODULE_DEVICE_TABLE(i2c, ina2xx_id);
692 
693 static const struct of_device_id __maybe_unused ina2xx_of_match[] = {
694 	{
695 		.compatible = "ti,ina219",
696 		.data = (void *)ina219
697 	},
698 	{
699 		.compatible = "ti,ina220",
700 		.data = (void *)ina219
701 	},
702 	{
703 		.compatible = "ti,ina226",
704 		.data = (void *)ina226
705 	},
706 	{
707 		.compatible = "ti,ina230",
708 		.data = (void *)ina226
709 	},
710 	{
711 		.compatible = "ti,ina231",
712 		.data = (void *)ina226
713 	},
714 	{ },
715 };
716 MODULE_DEVICE_TABLE(of, ina2xx_of_match);
717 
718 static struct i2c_driver ina2xx_driver = {
719 	.driver = {
720 		.name	= "ina2xx",
721 		.of_match_table = of_match_ptr(ina2xx_of_match),
722 	},
723 	.probe		= ina2xx_probe,
724 	.id_table	= ina2xx_id,
725 };
726 
727 module_i2c_driver(ina2xx_driver);
728 
729 MODULE_AUTHOR("Lothar Felten <l-felten@ti.com>");
730 MODULE_DESCRIPTION("ina2xx driver");
731 MODULE_LICENSE("GPL");
732