xref: /openbmc/linux/drivers/hwmon/ina2xx.c (revision b8265621)
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: http://www.ti.com/product/ina219
8  *
9  * INA220:
10  * Bi-Directional Current/Power Monitor with I2C Interface
11  * Datasheet: http://www.ti.com/product/ina220
12  *
13  * INA226:
14  * Bi-Directional Current/Power Monitor with I2C Interface
15  * Datasheet: http://www.ti.com/product/ina226
16  *
17  * INA230:
18  * Bi-directional Current/Power Monitor with I2C Interface
19  * Datasheet: http://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_device.h>
35 #include <linux/of.h>
36 #include <linux/delay.h>
37 #include <linux/util_macros.h>
38 #include <linux/regmap.h>
39 
40 #include <linux/platform_data/ina2xx.h>
41 
42 /* common register definitions */
43 #define INA2XX_CONFIG			0x00
44 #define INA2XX_SHUNT_VOLTAGE		0x01 /* readonly */
45 #define INA2XX_BUS_VOLTAGE		0x02 /* readonly */
46 #define INA2XX_POWER			0x03 /* readonly */
47 #define INA2XX_CURRENT			0x04 /* readonly */
48 #define INA2XX_CALIBRATION		0x05
49 
50 /* INA226 register definitions */
51 #define INA226_MASK_ENABLE		0x06
52 #define INA226_ALERT_LIMIT		0x07
53 #define INA226_DIE_ID			0xFF
54 
55 /* register count */
56 #define INA219_REGISTERS		6
57 #define INA226_REGISTERS		8
58 
59 #define INA2XX_MAX_REGISTERS		8
60 
61 /* settings - depend on use case */
62 #define INA219_CONFIG_DEFAULT		0x399F	/* PGA=8 */
63 #define INA226_CONFIG_DEFAULT		0x4527	/* averages=16 */
64 
65 /* worst case is 68.10 ms (~14.6Hz, ina219) */
66 #define INA2XX_CONVERSION_RATE		15
67 #define INA2XX_MAX_DELAY		69 /* worst case delay in ms */
68 
69 #define INA2XX_RSHUNT_DEFAULT		10000
70 
71 /* bit mask for reading the averaging setting in the configuration register */
72 #define INA226_AVG_RD_MASK		0x0E00
73 
74 #define INA226_READ_AVG(reg)		(((reg) & INA226_AVG_RD_MASK) >> 9)
75 #define INA226_SHIFT_AVG(val)		((val) << 9)
76 
77 /* bit number of alert functions in Mask/Enable Register */
78 #define INA226_SHUNT_OVER_VOLTAGE_BIT	15
79 #define INA226_SHUNT_UNDER_VOLTAGE_BIT	14
80 #define INA226_BUS_OVER_VOLTAGE_BIT	13
81 #define INA226_BUS_UNDER_VOLTAGE_BIT	12
82 #define INA226_POWER_OVER_LIMIT_BIT	11
83 
84 /* bit mask for alert config bits of Mask/Enable Register */
85 #define INA226_ALERT_CONFIG_MASK	0xFC00
86 #define INA226_ALERT_FUNCTION_FLAG	BIT(4)
87 
88 /* common attrs, ina226 attrs and NULL */
89 #define INA2XX_MAX_ATTRIBUTE_GROUPS	3
90 
91 /*
92  * Both bus voltage and shunt voltage conversion times for ina226 are set
93  * to 0b0100 on POR, which translates to 2200 microseconds in total.
94  */
95 #define INA226_TOTAL_CONV_TIME_DEFAULT	2200
96 
97 static struct regmap_config ina2xx_regmap_config = {
98 	.reg_bits = 8,
99 	.val_bits = 16,
100 };
101 
102 enum ina2xx_ids { ina219, ina226 };
103 
104 struct ina2xx_config {
105 	u16 config_default;
106 	int calibration_value;
107 	int registers;
108 	int shunt_div;
109 	int bus_voltage_shift;
110 	int bus_voltage_lsb;	/* uV */
111 	int power_lsb_factor;
112 };
113 
114 struct ina2xx_data {
115 	const struct ina2xx_config *config;
116 
117 	long rshunt;
118 	long current_lsb_uA;
119 	long power_lsb_uW;
120 	struct mutex config_lock;
121 	struct regmap *regmap;
122 
123 	const struct attribute_group *groups[INA2XX_MAX_ATTRIBUTE_GROUPS];
124 };
125 
126 static const struct ina2xx_config ina2xx_config[] = {
127 	[ina219] = {
128 		.config_default = INA219_CONFIG_DEFAULT,
129 		.calibration_value = 4096,
130 		.registers = INA219_REGISTERS,
131 		.shunt_div = 100,
132 		.bus_voltage_shift = 3,
133 		.bus_voltage_lsb = 4000,
134 		.power_lsb_factor = 20,
135 	},
136 	[ina226] = {
137 		.config_default = INA226_CONFIG_DEFAULT,
138 		.calibration_value = 2048,
139 		.registers = INA226_REGISTERS,
140 		.shunt_div = 400,
141 		.bus_voltage_shift = 0,
142 		.bus_voltage_lsb = 1250,
143 		.power_lsb_factor = 25,
144 	},
145 };
146 
147 /*
148  * Available averaging rates for ina226. The indices correspond with
149  * the bit values expected by the chip (according to the ina226 datasheet,
150  * table 3 AVG bit settings, found at
151  * http://www.ti.com/lit/ds/symlink/ina226.pdf.
152  */
153 static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
154 
155 static int ina226_reg_to_interval(u16 config)
156 {
157 	int avg = ina226_avg_tab[INA226_READ_AVG(config)];
158 
159 	/*
160 	 * Multiply the total conversion time by the number of averages.
161 	 * Return the result in milliseconds.
162 	 */
163 	return DIV_ROUND_CLOSEST(avg * INA226_TOTAL_CONV_TIME_DEFAULT, 1000);
164 }
165 
166 /*
167  * Return the new, shifted AVG field value of CONFIG register,
168  * to use with regmap_update_bits
169  */
170 static u16 ina226_interval_to_reg(int interval)
171 {
172 	int avg, avg_bits;
173 
174 	avg = DIV_ROUND_CLOSEST(interval * 1000,
175 				INA226_TOTAL_CONV_TIME_DEFAULT);
176 	avg_bits = find_closest(avg, ina226_avg_tab,
177 				ARRAY_SIZE(ina226_avg_tab));
178 
179 	return INA226_SHIFT_AVG(avg_bits);
180 }
181 
182 /*
183  * Calibration register is set to the best value, which eliminates
184  * truncation errors on calculating current register in hardware.
185  * According to datasheet (eq. 3) the best values are 2048 for
186  * ina226 and 4096 for ina219. They are hardcoded as calibration_value.
187  */
188 static int ina2xx_calibrate(struct ina2xx_data *data)
189 {
190 	return regmap_write(data->regmap, INA2XX_CALIBRATION,
191 			    data->config->calibration_value);
192 }
193 
194 /*
195  * Initialize the configuration and calibration registers.
196  */
197 static int ina2xx_init(struct ina2xx_data *data)
198 {
199 	int ret = regmap_write(data->regmap, INA2XX_CONFIG,
200 			       data->config->config_default);
201 	if (ret < 0)
202 		return ret;
203 
204 	return ina2xx_calibrate(data);
205 }
206 
207 static int ina2xx_read_reg(struct device *dev, int reg, unsigned int *regval)
208 {
209 	struct ina2xx_data *data = dev_get_drvdata(dev);
210 	int ret, retry;
211 
212 	dev_dbg(dev, "Starting register %d read\n", reg);
213 
214 	for (retry = 5; retry; retry--) {
215 
216 		ret = regmap_read(data->regmap, reg, regval);
217 		if (ret < 0)
218 			return ret;
219 
220 		dev_dbg(dev, "read %d, val = 0x%04x\n", reg, *regval);
221 
222 		/*
223 		 * If the current value in the calibration register is 0, the
224 		 * power and current registers will also remain at 0. In case
225 		 * the chip has been reset let's check the calibration
226 		 * register and reinitialize if needed.
227 		 * We do that extra read of the calibration register if there
228 		 * is some hint of a chip reset.
229 		 */
230 		if (*regval == 0) {
231 			unsigned int cal;
232 
233 			ret = regmap_read(data->regmap, INA2XX_CALIBRATION,
234 					  &cal);
235 			if (ret < 0)
236 				return ret;
237 
238 			if (cal == 0) {
239 				dev_warn(dev, "chip not calibrated, reinitializing\n");
240 
241 				ret = ina2xx_init(data);
242 				if (ret < 0)
243 					return ret;
244 				/*
245 				 * Let's make sure the power and current
246 				 * registers have been updated before trying
247 				 * again.
248 				 */
249 				msleep(INA2XX_MAX_DELAY);
250 				continue;
251 			}
252 		}
253 		return 0;
254 	}
255 
256 	/*
257 	 * If we're here then although all write operations succeeded, the
258 	 * chip still returns 0 in the calibration register. Nothing more we
259 	 * can do here.
260 	 */
261 	dev_err(dev, "unable to reinitialize the chip\n");
262 	return -ENODEV;
263 }
264 
265 static int ina2xx_get_value(struct ina2xx_data *data, u8 reg,
266 			    unsigned int regval)
267 {
268 	int val;
269 
270 	switch (reg) {
271 	case INA2XX_SHUNT_VOLTAGE:
272 		/* signed register */
273 		val = DIV_ROUND_CLOSEST((s16)regval, data->config->shunt_div);
274 		break;
275 	case INA2XX_BUS_VOLTAGE:
276 		val = (regval >> data->config->bus_voltage_shift)
277 		  * data->config->bus_voltage_lsb;
278 		val = DIV_ROUND_CLOSEST(val, 1000);
279 		break;
280 	case INA2XX_POWER:
281 		val = regval * data->power_lsb_uW;
282 		break;
283 	case INA2XX_CURRENT:
284 		/* signed register, result in mA */
285 		val = (s16)regval * data->current_lsb_uA;
286 		val = DIV_ROUND_CLOSEST(val, 1000);
287 		break;
288 	case INA2XX_CALIBRATION:
289 		val = regval;
290 		break;
291 	default:
292 		/* programmer goofed */
293 		WARN_ON_ONCE(1);
294 		val = 0;
295 		break;
296 	}
297 
298 	return val;
299 }
300 
301 static ssize_t ina2xx_value_show(struct device *dev,
302 				 struct device_attribute *da, char *buf)
303 {
304 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
305 	struct ina2xx_data *data = dev_get_drvdata(dev);
306 	unsigned int regval;
307 
308 	int err = ina2xx_read_reg(dev, attr->index, &regval);
309 
310 	if (err < 0)
311 		return err;
312 
313 	return snprintf(buf, PAGE_SIZE, "%d\n",
314 			ina2xx_get_value(data, attr->index, regval));
315 }
316 
317 static int ina226_reg_to_alert(struct ina2xx_data *data, u8 bit, u16 regval)
318 {
319 	int reg;
320 
321 	switch (bit) {
322 	case INA226_SHUNT_OVER_VOLTAGE_BIT:
323 	case INA226_SHUNT_UNDER_VOLTAGE_BIT:
324 		reg = INA2XX_SHUNT_VOLTAGE;
325 		break;
326 	case INA226_BUS_OVER_VOLTAGE_BIT:
327 	case INA226_BUS_UNDER_VOLTAGE_BIT:
328 		reg = INA2XX_BUS_VOLTAGE;
329 		break;
330 	case INA226_POWER_OVER_LIMIT_BIT:
331 		reg = INA2XX_POWER;
332 		break;
333 	default:
334 		/* programmer goofed */
335 		WARN_ON_ONCE(1);
336 		return 0;
337 	}
338 
339 	return ina2xx_get_value(data, reg, regval);
340 }
341 
342 /*
343  * Turns alert limit values into register values.
344  * Opposite of the formula in ina2xx_get_value().
345  */
346 static s16 ina226_alert_to_reg(struct ina2xx_data *data, u8 bit, int val)
347 {
348 	switch (bit) {
349 	case INA226_SHUNT_OVER_VOLTAGE_BIT:
350 	case INA226_SHUNT_UNDER_VOLTAGE_BIT:
351 		val *= data->config->shunt_div;
352 		return clamp_val(val, SHRT_MIN, SHRT_MAX);
353 	case INA226_BUS_OVER_VOLTAGE_BIT:
354 	case INA226_BUS_UNDER_VOLTAGE_BIT:
355 		val = (val * 1000) << data->config->bus_voltage_shift;
356 		val = DIV_ROUND_CLOSEST(val, data->config->bus_voltage_lsb);
357 		return clamp_val(val, 0, SHRT_MAX);
358 	case INA226_POWER_OVER_LIMIT_BIT:
359 		val = DIV_ROUND_CLOSEST(val, data->power_lsb_uW);
360 		return clamp_val(val, 0, USHRT_MAX);
361 	default:
362 		/* programmer goofed */
363 		WARN_ON_ONCE(1);
364 		return 0;
365 	}
366 }
367 
368 static ssize_t ina226_alert_show(struct device *dev,
369 				 struct device_attribute *da, char *buf)
370 {
371 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
372 	struct ina2xx_data *data = dev_get_drvdata(dev);
373 	int regval;
374 	int val = 0;
375 	int ret;
376 
377 	mutex_lock(&data->config_lock);
378 	ret = regmap_read(data->regmap, INA226_MASK_ENABLE, &regval);
379 	if (ret)
380 		goto abort;
381 
382 	if (regval & BIT(attr->index)) {
383 		ret = regmap_read(data->regmap, INA226_ALERT_LIMIT, &regval);
384 		if (ret)
385 			goto abort;
386 		val = ina226_reg_to_alert(data, attr->index, regval);
387 	}
388 
389 	ret = snprintf(buf, PAGE_SIZE, "%d\n", val);
390 abort:
391 	mutex_unlock(&data->config_lock);
392 	return ret;
393 }
394 
395 static ssize_t ina226_alert_store(struct device *dev,
396 				  struct device_attribute *da,
397 				  const char *buf, size_t count)
398 {
399 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
400 	struct ina2xx_data *data = dev_get_drvdata(dev);
401 	unsigned long val;
402 	int ret;
403 
404 	ret = kstrtoul(buf, 10, &val);
405 	if (ret < 0)
406 		return ret;
407 
408 	/*
409 	 * Clear all alerts first to avoid accidentally triggering ALERT pin
410 	 * due to register write sequence. Then, only enable the alert
411 	 * if the value is non-zero.
412 	 */
413 	mutex_lock(&data->config_lock);
414 	ret = regmap_update_bits(data->regmap, INA226_MASK_ENABLE,
415 				 INA226_ALERT_CONFIG_MASK, 0);
416 	if (ret < 0)
417 		goto abort;
418 
419 	ret = regmap_write(data->regmap, INA226_ALERT_LIMIT,
420 			   ina226_alert_to_reg(data, attr->index, val));
421 	if (ret < 0)
422 		goto abort;
423 
424 	if (val != 0) {
425 		ret = regmap_update_bits(data->regmap, INA226_MASK_ENABLE,
426 					 INA226_ALERT_CONFIG_MASK,
427 					 BIT(attr->index));
428 		if (ret < 0)
429 			goto abort;
430 	}
431 
432 	ret = count;
433 abort:
434 	mutex_unlock(&data->config_lock);
435 	return ret;
436 }
437 
438 static ssize_t ina226_alarm_show(struct device *dev,
439 				 struct device_attribute *da, char *buf)
440 {
441 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
442 	struct ina2xx_data *data = dev_get_drvdata(dev);
443 	int regval;
444 	int alarm = 0;
445 	int ret;
446 
447 	ret = regmap_read(data->regmap, INA226_MASK_ENABLE, &regval);
448 	if (ret)
449 		return ret;
450 
451 	alarm = (regval & BIT(attr->index)) &&
452 		(regval & INA226_ALERT_FUNCTION_FLAG);
453 	return snprintf(buf, PAGE_SIZE, "%d\n", alarm);
454 }
455 
456 /*
457  * In order to keep calibration register value fixed, the product
458  * of current_lsb and shunt_resistor should also be fixed and equal
459  * to shunt_voltage_lsb = 1 / shunt_div multiplied by 10^9 in order
460  * to keep the scale.
461  */
462 static int ina2xx_set_shunt(struct ina2xx_data *data, long val)
463 {
464 	unsigned int dividend = DIV_ROUND_CLOSEST(1000000000,
465 						  data->config->shunt_div);
466 	if (val <= 0 || val > dividend)
467 		return -EINVAL;
468 
469 	mutex_lock(&data->config_lock);
470 	data->rshunt = val;
471 	data->current_lsb_uA = DIV_ROUND_CLOSEST(dividend, val);
472 	data->power_lsb_uW = data->config->power_lsb_factor *
473 			     data->current_lsb_uA;
474 	mutex_unlock(&data->config_lock);
475 
476 	return 0;
477 }
478 
479 static ssize_t ina2xx_shunt_show(struct device *dev,
480 				 struct device_attribute *da, char *buf)
481 {
482 	struct ina2xx_data *data = dev_get_drvdata(dev);
483 
484 	return snprintf(buf, PAGE_SIZE, "%li\n", data->rshunt);
485 }
486 
487 static ssize_t ina2xx_shunt_store(struct device *dev,
488 				  struct device_attribute *da,
489 				  const char *buf, size_t count)
490 {
491 	unsigned long val;
492 	int status;
493 	struct ina2xx_data *data = dev_get_drvdata(dev);
494 
495 	status = kstrtoul(buf, 10, &val);
496 	if (status < 0)
497 		return status;
498 
499 	status = ina2xx_set_shunt(data, val);
500 	if (status < 0)
501 		return status;
502 	return count;
503 }
504 
505 static ssize_t ina226_interval_store(struct device *dev,
506 				     struct device_attribute *da,
507 				     const char *buf, size_t count)
508 {
509 	struct ina2xx_data *data = dev_get_drvdata(dev);
510 	unsigned long val;
511 	int status;
512 
513 	status = kstrtoul(buf, 10, &val);
514 	if (status < 0)
515 		return status;
516 
517 	if (val > INT_MAX || val == 0)
518 		return -EINVAL;
519 
520 	status = regmap_update_bits(data->regmap, INA2XX_CONFIG,
521 				    INA226_AVG_RD_MASK,
522 				    ina226_interval_to_reg(val));
523 	if (status < 0)
524 		return status;
525 
526 	return count;
527 }
528 
529 static ssize_t ina226_interval_show(struct device *dev,
530 				    struct device_attribute *da, char *buf)
531 {
532 	struct ina2xx_data *data = dev_get_drvdata(dev);
533 	int status;
534 	unsigned int regval;
535 
536 	status = regmap_read(data->regmap, INA2XX_CONFIG, &regval);
537 	if (status)
538 		return status;
539 
540 	return snprintf(buf, PAGE_SIZE, "%d\n", ina226_reg_to_interval(regval));
541 }
542 
543 /* shunt voltage */
544 static SENSOR_DEVICE_ATTR_RO(in0_input, ina2xx_value, INA2XX_SHUNT_VOLTAGE);
545 /* shunt voltage over/under voltage alert setting and alarm */
546 static SENSOR_DEVICE_ATTR_RW(in0_crit, ina226_alert,
547 			     INA226_SHUNT_OVER_VOLTAGE_BIT);
548 static SENSOR_DEVICE_ATTR_RW(in0_lcrit, ina226_alert,
549 			     INA226_SHUNT_UNDER_VOLTAGE_BIT);
550 static SENSOR_DEVICE_ATTR_RO(in0_crit_alarm, ina226_alarm,
551 			     INA226_SHUNT_OVER_VOLTAGE_BIT);
552 static SENSOR_DEVICE_ATTR_RO(in0_lcrit_alarm, ina226_alarm,
553 			     INA226_SHUNT_UNDER_VOLTAGE_BIT);
554 
555 /* bus voltage */
556 static SENSOR_DEVICE_ATTR_RO(in1_input, ina2xx_value, INA2XX_BUS_VOLTAGE);
557 /* bus voltage over/under voltage alert setting and alarm */
558 static SENSOR_DEVICE_ATTR_RW(in1_crit, ina226_alert,
559 			     INA226_BUS_OVER_VOLTAGE_BIT);
560 static SENSOR_DEVICE_ATTR_RW(in1_lcrit, ina226_alert,
561 			     INA226_BUS_UNDER_VOLTAGE_BIT);
562 static SENSOR_DEVICE_ATTR_RO(in1_crit_alarm, ina226_alarm,
563 			     INA226_BUS_OVER_VOLTAGE_BIT);
564 static SENSOR_DEVICE_ATTR_RO(in1_lcrit_alarm, ina226_alarm,
565 			     INA226_BUS_UNDER_VOLTAGE_BIT);
566 
567 /* calculated current */
568 static SENSOR_DEVICE_ATTR_RO(curr1_input, ina2xx_value, INA2XX_CURRENT);
569 
570 /* calculated power */
571 static SENSOR_DEVICE_ATTR_RO(power1_input, ina2xx_value, INA2XX_POWER);
572 /* over-limit power alert setting and alarm */
573 static SENSOR_DEVICE_ATTR_RW(power1_crit, ina226_alert,
574 			     INA226_POWER_OVER_LIMIT_BIT);
575 static SENSOR_DEVICE_ATTR_RO(power1_crit_alarm, ina226_alarm,
576 			     INA226_POWER_OVER_LIMIT_BIT);
577 
578 /* shunt resistance */
579 static SENSOR_DEVICE_ATTR_RW(shunt_resistor, ina2xx_shunt, INA2XX_CALIBRATION);
580 
581 /* update interval (ina226 only) */
582 static SENSOR_DEVICE_ATTR_RW(update_interval, ina226_interval, 0);
583 
584 /* pointers to created device attributes */
585 static struct attribute *ina2xx_attrs[] = {
586 	&sensor_dev_attr_in0_input.dev_attr.attr,
587 	&sensor_dev_attr_in1_input.dev_attr.attr,
588 	&sensor_dev_attr_curr1_input.dev_attr.attr,
589 	&sensor_dev_attr_power1_input.dev_attr.attr,
590 	&sensor_dev_attr_shunt_resistor.dev_attr.attr,
591 	NULL,
592 };
593 
594 static const struct attribute_group ina2xx_group = {
595 	.attrs = ina2xx_attrs,
596 };
597 
598 static struct attribute *ina226_attrs[] = {
599 	&sensor_dev_attr_in0_crit.dev_attr.attr,
600 	&sensor_dev_attr_in0_lcrit.dev_attr.attr,
601 	&sensor_dev_attr_in0_crit_alarm.dev_attr.attr,
602 	&sensor_dev_attr_in0_lcrit_alarm.dev_attr.attr,
603 	&sensor_dev_attr_in1_crit.dev_attr.attr,
604 	&sensor_dev_attr_in1_lcrit.dev_attr.attr,
605 	&sensor_dev_attr_in1_crit_alarm.dev_attr.attr,
606 	&sensor_dev_attr_in1_lcrit_alarm.dev_attr.attr,
607 	&sensor_dev_attr_power1_crit.dev_attr.attr,
608 	&sensor_dev_attr_power1_crit_alarm.dev_attr.attr,
609 	&sensor_dev_attr_update_interval.dev_attr.attr,
610 	NULL,
611 };
612 
613 static const struct attribute_group ina226_group = {
614 	.attrs = ina226_attrs,
615 };
616 
617 static int ina2xx_probe(struct i2c_client *client,
618 			const struct i2c_device_id *id)
619 {
620 	struct device *dev = &client->dev;
621 	struct ina2xx_data *data;
622 	struct device *hwmon_dev;
623 	u32 val;
624 	int ret, group = 0;
625 	enum ina2xx_ids chip;
626 
627 	if (client->dev.of_node)
628 		chip = (enum ina2xx_ids)of_device_get_match_data(&client->dev);
629 	else
630 		chip = id->driver_data;
631 
632 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
633 	if (!data)
634 		return -ENOMEM;
635 
636 	/* set the device type */
637 	data->config = &ina2xx_config[chip];
638 	mutex_init(&data->config_lock);
639 
640 	if (of_property_read_u32(dev->of_node, "shunt-resistor", &val) < 0) {
641 		struct ina2xx_platform_data *pdata = dev_get_platdata(dev);
642 
643 		if (pdata)
644 			val = pdata->shunt_uohms;
645 		else
646 			val = INA2XX_RSHUNT_DEFAULT;
647 	}
648 
649 	ina2xx_set_shunt(data, val);
650 
651 	ina2xx_regmap_config.max_register = data->config->registers;
652 
653 	data->regmap = devm_regmap_init_i2c(client, &ina2xx_regmap_config);
654 	if (IS_ERR(data->regmap)) {
655 		dev_err(dev, "failed to allocate register map\n");
656 		return PTR_ERR(data->regmap);
657 	}
658 
659 	ret = ina2xx_init(data);
660 	if (ret < 0) {
661 		dev_err(dev, "error configuring the device: %d\n", ret);
662 		return -ENODEV;
663 	}
664 
665 	data->groups[group++] = &ina2xx_group;
666 	if (chip == ina226)
667 		data->groups[group++] = &ina226_group;
668 
669 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
670 							   data, data->groups);
671 	if (IS_ERR(hwmon_dev))
672 		return PTR_ERR(hwmon_dev);
673 
674 	dev_info(dev, "power monitor %s (Rshunt = %li uOhm)\n",
675 		 client->name, data->rshunt);
676 
677 	return 0;
678 }
679 
680 static const struct i2c_device_id ina2xx_id[] = {
681 	{ "ina219", ina219 },
682 	{ "ina220", ina219 },
683 	{ "ina226", ina226 },
684 	{ "ina230", ina226 },
685 	{ "ina231", ina226 },
686 	{ }
687 };
688 MODULE_DEVICE_TABLE(i2c, ina2xx_id);
689 
690 static const struct of_device_id __maybe_unused ina2xx_of_match[] = {
691 	{
692 		.compatible = "ti,ina219",
693 		.data = (void *)ina219
694 	},
695 	{
696 		.compatible = "ti,ina220",
697 		.data = (void *)ina219
698 	},
699 	{
700 		.compatible = "ti,ina226",
701 		.data = (void *)ina226
702 	},
703 	{
704 		.compatible = "ti,ina230",
705 		.data = (void *)ina226
706 	},
707 	{
708 		.compatible = "ti,ina231",
709 		.data = (void *)ina226
710 	},
711 	{ },
712 };
713 MODULE_DEVICE_TABLE(of, ina2xx_of_match);
714 
715 static struct i2c_driver ina2xx_driver = {
716 	.driver = {
717 		.name	= "ina2xx",
718 		.of_match_table = of_match_ptr(ina2xx_of_match),
719 	},
720 	.probe		= ina2xx_probe,
721 	.id_table	= ina2xx_id,
722 };
723 
724 module_i2c_driver(ina2xx_driver);
725 
726 MODULE_AUTHOR("Lothar Felten <l-felten@ti.com>");
727 MODULE_DESCRIPTION("ina2xx driver");
728 MODULE_LICENSE("GPL");
729