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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_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
97static struct regmap_config ina2xx_regmap_config = {
98 .reg_bits = 8,
99 .val_bits = 16,
100};
101
102enum ina2xx_ids { ina219, ina226 };
103
104struct 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
114struct 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
126static 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 * https://www.ti.com/lit/ds/symlink/ina226.pdf.
152 */
153static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
154
155static 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 */
170static 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 */
188static 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 */
197static 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
207static 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
265static 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
301static 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, ®val);
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
317static 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 */
346static 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
368static 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, ®val);
379 if (ret)
380 goto abort;
381
382 if (regval & BIT(attr->index)) {
383 ret = regmap_read(data->regmap, INA226_ALERT_LIMIT, ®val);
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);
390abort:
391 mutex_unlock(&data->config_lock);
392 return ret;
393}
394
395static 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;
433abort:
434 mutex_unlock(&data->config_lock);
435 return ret;
436}
437
438static 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, ®val);
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 */
462static 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
479static 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
487static 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
505static 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
529static 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, ®val);
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 */
544static SENSOR_DEVICE_ATTR_RO(in0_input, ina2xx_value, INA2XX_SHUNT_VOLTAGE);
545/* shunt voltage over/under voltage alert setting and alarm */
546static SENSOR_DEVICE_ATTR_RW(in0_crit, ina226_alert,
547 INA226_SHUNT_OVER_VOLTAGE_BIT);
548static SENSOR_DEVICE_ATTR_RW(in0_lcrit, ina226_alert,
549 INA226_SHUNT_UNDER_VOLTAGE_BIT);
550static SENSOR_DEVICE_ATTR_RO(in0_crit_alarm, ina226_alarm,
551 INA226_SHUNT_OVER_VOLTAGE_BIT);
552static SENSOR_DEVICE_ATTR_RO(in0_lcrit_alarm, ina226_alarm,
553 INA226_SHUNT_UNDER_VOLTAGE_BIT);
554
555/* bus voltage */
556static SENSOR_DEVICE_ATTR_RO(in1_input, ina2xx_value, INA2XX_BUS_VOLTAGE);
557/* bus voltage over/under voltage alert setting and alarm */
558static SENSOR_DEVICE_ATTR_RW(in1_crit, ina226_alert,
559 INA226_BUS_OVER_VOLTAGE_BIT);
560static SENSOR_DEVICE_ATTR_RW(in1_lcrit, ina226_alert,
561 INA226_BUS_UNDER_VOLTAGE_BIT);
562static SENSOR_DEVICE_ATTR_RO(in1_crit_alarm, ina226_alarm,
563 INA226_BUS_OVER_VOLTAGE_BIT);
564static SENSOR_DEVICE_ATTR_RO(in1_lcrit_alarm, ina226_alarm,
565 INA226_BUS_UNDER_VOLTAGE_BIT);
566
567/* calculated current */
568static SENSOR_DEVICE_ATTR_RO(curr1_input, ina2xx_value, INA2XX_CURRENT);
569
570/* calculated power */
571static SENSOR_DEVICE_ATTR_RO(power1_input, ina2xx_value, INA2XX_POWER);
572/* over-limit power alert setting and alarm */
573static SENSOR_DEVICE_ATTR_RW(power1_crit, ina226_alert,
574 INA226_POWER_OVER_LIMIT_BIT);
575static SENSOR_DEVICE_ATTR_RO(power1_crit_alarm, ina226_alarm,
576 INA226_POWER_OVER_LIMIT_BIT);
577
578/* shunt resistance */
579static SENSOR_DEVICE_ATTR_RW(shunt_resistor, ina2xx_shunt, INA2XX_CALIBRATION);
580
581/* update interval (ina226 only) */
582static SENSOR_DEVICE_ATTR_RW(update_interval, ina226_interval, 0);
583
584/* pointers to created device attributes */
585static 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
594static const struct attribute_group ina2xx_group = {
595 .attrs = ina2xx_attrs,
596};
597
598static 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
613static const struct attribute_group ina226_group = {
614 .attrs = ina226_attrs,
615};
616
617static 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
680static const struct i2c_device_id ina2xx_id[] = {
681 { "ina219", ina219 },
682 { "ina220", ina219 },
683 { "ina226", ina226 },
684 { "ina230", ina226 },
685 { "ina231", ina226 },
686 { }
687};
688MODULE_DEVICE_TABLE(i2c, ina2xx_id);
689
690static 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};
713MODULE_DEVICE_TABLE(of, ina2xx_of_match);
714
715static 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
724module_i2c_driver(ina2xx_driver);
725
726MODULE_AUTHOR("Lothar Felten <l-felten@ti.com>");
727MODULE_DESCRIPTION("ina2xx driver");
728MODULE_LICENSE("GPL");
1/*
2 * Driver for Texas Instruments INA219, INA226 power monitor chips
3 *
4 * INA219:
5 * Zero Drift Bi-Directional Current/Power Monitor with I2C Interface
6 * Datasheet: http://www.ti.com/product/ina219
7 *
8 * INA220:
9 * Bi-Directional Current/Power Monitor with I2C Interface
10 * Datasheet: http://www.ti.com/product/ina220
11 *
12 * INA226:
13 * Bi-Directional Current/Power Monitor with I2C Interface
14 * Datasheet: http://www.ti.com/product/ina226
15 *
16 * INA230:
17 * Bi-directional Current/Power Monitor with I2C Interface
18 * Datasheet: http://www.ti.com/product/ina230
19 *
20 * Copyright (C) 2012 Lothar Felten <l-felten@ti.com>
21 * Thanks to Jan Volkering
22 *
23 * This program is free software; you can redistribute it and/or modify
24 * it under the terms of the GNU General Public License as published by
25 * the Free Software Foundation; version 2 of the License.
26 */
27
28#include <linux/kernel.h>
29#include <linux/module.h>
30#include <linux/init.h>
31#include <linux/err.h>
32#include <linux/slab.h>
33#include <linux/i2c.h>
34#include <linux/hwmon.h>
35#include <linux/hwmon-sysfs.h>
36#include <linux/jiffies.h>
37#include <linux/of.h>
38#include <linux/delay.h>
39#include <linux/util_macros.h>
40#include <linux/regmap.h>
41
42#include <linux/platform_data/ina2xx.h>
43
44/* common register definitions */
45#define INA2XX_CONFIG 0x00
46#define INA2XX_SHUNT_VOLTAGE 0x01 /* readonly */
47#define INA2XX_BUS_VOLTAGE 0x02 /* readonly */
48#define INA2XX_POWER 0x03 /* readonly */
49#define INA2XX_CURRENT 0x04 /* readonly */
50#define INA2XX_CALIBRATION 0x05
51
52/* INA226 register definitions */
53#define INA226_MASK_ENABLE 0x06
54#define INA226_ALERT_LIMIT 0x07
55#define INA226_DIE_ID 0xFF
56
57/* register count */
58#define INA219_REGISTERS 6
59#define INA226_REGISTERS 8
60
61#define INA2XX_MAX_REGISTERS 8
62
63/* settings - depend on use case */
64#define INA219_CONFIG_DEFAULT 0x399F /* PGA=8 */
65#define INA226_CONFIG_DEFAULT 0x4527 /* averages=16 */
66
67/* worst case is 68.10 ms (~14.6Hz, ina219) */
68#define INA2XX_CONVERSION_RATE 15
69#define INA2XX_MAX_DELAY 69 /* worst case delay in ms */
70
71#define INA2XX_RSHUNT_DEFAULT 10000
72
73/* bit mask for reading the averaging setting in the configuration register */
74#define INA226_AVG_RD_MASK 0x0E00
75
76#define INA226_READ_AVG(reg) (((reg) & INA226_AVG_RD_MASK) >> 9)
77#define INA226_SHIFT_AVG(val) ((val) << 9)
78
79/* common attrs, ina226 attrs and NULL */
80#define INA2XX_MAX_ATTRIBUTE_GROUPS 3
81
82/*
83 * Both bus voltage and shunt voltage conversion times for ina226 are set
84 * to 0b0100 on POR, which translates to 2200 microseconds in total.
85 */
86#define INA226_TOTAL_CONV_TIME_DEFAULT 2200
87
88static struct regmap_config ina2xx_regmap_config = {
89 .reg_bits = 8,
90 .val_bits = 16,
91};
92
93enum ina2xx_ids { ina219, ina226 };
94
95struct ina2xx_config {
96 u16 config_default;
97 int calibration_factor;
98 int registers;
99 int shunt_div;
100 int bus_voltage_shift;
101 int bus_voltage_lsb; /* uV */
102 int power_lsb; /* uW */
103};
104
105struct ina2xx_data {
106 const struct ina2xx_config *config;
107
108 long rshunt;
109 struct mutex config_lock;
110 struct regmap *regmap;
111
112 const struct attribute_group *groups[INA2XX_MAX_ATTRIBUTE_GROUPS];
113};
114
115static const struct ina2xx_config ina2xx_config[] = {
116 [ina219] = {
117 .config_default = INA219_CONFIG_DEFAULT,
118 .calibration_factor = 40960000,
119 .registers = INA219_REGISTERS,
120 .shunt_div = 100,
121 .bus_voltage_shift = 3,
122 .bus_voltage_lsb = 4000,
123 .power_lsb = 20000,
124 },
125 [ina226] = {
126 .config_default = INA226_CONFIG_DEFAULT,
127 .calibration_factor = 5120000,
128 .registers = INA226_REGISTERS,
129 .shunt_div = 400,
130 .bus_voltage_shift = 0,
131 .bus_voltage_lsb = 1250,
132 .power_lsb = 25000,
133 },
134};
135
136/*
137 * Available averaging rates for ina226. The indices correspond with
138 * the bit values expected by the chip (according to the ina226 datasheet,
139 * table 3 AVG bit settings, found at
140 * http://www.ti.com/lit/ds/symlink/ina226.pdf.
141 */
142static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
143
144static int ina226_reg_to_interval(u16 config)
145{
146 int avg = ina226_avg_tab[INA226_READ_AVG(config)];
147
148 /*
149 * Multiply the total conversion time by the number of averages.
150 * Return the result in milliseconds.
151 */
152 return DIV_ROUND_CLOSEST(avg * INA226_TOTAL_CONV_TIME_DEFAULT, 1000);
153}
154
155/*
156 * Return the new, shifted AVG field value of CONFIG register,
157 * to use with regmap_update_bits
158 */
159static u16 ina226_interval_to_reg(int interval)
160{
161 int avg, avg_bits;
162
163 avg = DIV_ROUND_CLOSEST(interval * 1000,
164 INA226_TOTAL_CONV_TIME_DEFAULT);
165 avg_bits = find_closest(avg, ina226_avg_tab,
166 ARRAY_SIZE(ina226_avg_tab));
167
168 return INA226_SHIFT_AVG(avg_bits);
169}
170
171static int ina2xx_calibrate(struct ina2xx_data *data)
172{
173 u16 val = DIV_ROUND_CLOSEST(data->config->calibration_factor,
174 data->rshunt);
175
176 return regmap_write(data->regmap, INA2XX_CALIBRATION, val);
177}
178
179/*
180 * Initialize the configuration and calibration registers.
181 */
182static int ina2xx_init(struct ina2xx_data *data)
183{
184 int ret = regmap_write(data->regmap, INA2XX_CONFIG,
185 data->config->config_default);
186 if (ret < 0)
187 return ret;
188
189 /*
190 * Set current LSB to 1mA, shunt is in uOhms
191 * (equation 13 in datasheet).
192 */
193 return ina2xx_calibrate(data);
194}
195
196static int ina2xx_read_reg(struct device *dev, int reg, unsigned int *regval)
197{
198 struct ina2xx_data *data = dev_get_drvdata(dev);
199 int ret, retry;
200
201 dev_dbg(dev, "Starting register %d read\n", reg);
202
203 for (retry = 5; retry; retry--) {
204
205 ret = regmap_read(data->regmap, reg, regval);
206 if (ret < 0)
207 return ret;
208
209 dev_dbg(dev, "read %d, val = 0x%04x\n", reg, *regval);
210
211 /*
212 * If the current value in the calibration register is 0, the
213 * power and current registers will also remain at 0. In case
214 * the chip has been reset let's check the calibration
215 * register and reinitialize if needed.
216 * We do that extra read of the calibration register if there
217 * is some hint of a chip reset.
218 */
219 if (*regval == 0) {
220 unsigned int cal;
221
222 ret = regmap_read(data->regmap, INA2XX_CALIBRATION,
223 &cal);
224 if (ret < 0)
225 return ret;
226
227 if (cal == 0) {
228 dev_warn(dev, "chip not calibrated, reinitializing\n");
229
230 ret = ina2xx_init(data);
231 if (ret < 0)
232 return ret;
233 /*
234 * Let's make sure the power and current
235 * registers have been updated before trying
236 * again.
237 */
238 msleep(INA2XX_MAX_DELAY);
239 continue;
240 }
241 }
242 return 0;
243 }
244
245 /*
246 * If we're here then although all write operations succeeded, the
247 * chip still returns 0 in the calibration register. Nothing more we
248 * can do here.
249 */
250 dev_err(dev, "unable to reinitialize the chip\n");
251 return -ENODEV;
252}
253
254static int ina2xx_get_value(struct ina2xx_data *data, u8 reg,
255 unsigned int regval)
256{
257 int val;
258
259 switch (reg) {
260 case INA2XX_SHUNT_VOLTAGE:
261 /* signed register */
262 val = DIV_ROUND_CLOSEST((s16)regval, data->config->shunt_div);
263 break;
264 case INA2XX_BUS_VOLTAGE:
265 val = (regval >> data->config->bus_voltage_shift)
266 * data->config->bus_voltage_lsb;
267 val = DIV_ROUND_CLOSEST(val, 1000);
268 break;
269 case INA2XX_POWER:
270 val = regval * data->config->power_lsb;
271 break;
272 case INA2XX_CURRENT:
273 /* signed register, LSB=1mA (selected), in mA */
274 val = (s16)regval;
275 break;
276 case INA2XX_CALIBRATION:
277 val = DIV_ROUND_CLOSEST(data->config->calibration_factor,
278 regval);
279 break;
280 default:
281 /* programmer goofed */
282 WARN_ON_ONCE(1);
283 val = 0;
284 break;
285 }
286
287 return val;
288}
289
290static ssize_t ina2xx_show_value(struct device *dev,
291 struct device_attribute *da, char *buf)
292{
293 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
294 struct ina2xx_data *data = dev_get_drvdata(dev);
295 unsigned int regval;
296
297 int err = ina2xx_read_reg(dev, attr->index, ®val);
298
299 if (err < 0)
300 return err;
301
302 return snprintf(buf, PAGE_SIZE, "%d\n",
303 ina2xx_get_value(data, attr->index, regval));
304}
305
306static ssize_t ina2xx_set_shunt(struct device *dev,
307 struct device_attribute *da,
308 const char *buf, size_t count)
309{
310 unsigned long val;
311 int status;
312 struct ina2xx_data *data = dev_get_drvdata(dev);
313
314 status = kstrtoul(buf, 10, &val);
315 if (status < 0)
316 return status;
317
318 if (val == 0 ||
319 /* Values greater than the calibration factor make no sense. */
320 val > data->config->calibration_factor)
321 return -EINVAL;
322
323 mutex_lock(&data->config_lock);
324 data->rshunt = val;
325 status = ina2xx_calibrate(data);
326 mutex_unlock(&data->config_lock);
327 if (status < 0)
328 return status;
329
330 return count;
331}
332
333static ssize_t ina226_set_interval(struct device *dev,
334 struct device_attribute *da,
335 const char *buf, size_t count)
336{
337 struct ina2xx_data *data = dev_get_drvdata(dev);
338 unsigned long val;
339 int status;
340
341 status = kstrtoul(buf, 10, &val);
342 if (status < 0)
343 return status;
344
345 if (val > INT_MAX || val == 0)
346 return -EINVAL;
347
348 status = regmap_update_bits(data->regmap, INA2XX_CONFIG,
349 INA226_AVG_RD_MASK,
350 ina226_interval_to_reg(val));
351 if (status < 0)
352 return status;
353
354 return count;
355}
356
357static ssize_t ina226_show_interval(struct device *dev,
358 struct device_attribute *da, char *buf)
359{
360 struct ina2xx_data *data = dev_get_drvdata(dev);
361 int status;
362 unsigned int regval;
363
364 status = regmap_read(data->regmap, INA2XX_CONFIG, ®val);
365 if (status)
366 return status;
367
368 return snprintf(buf, PAGE_SIZE, "%d\n", ina226_reg_to_interval(regval));
369}
370
371/* shunt voltage */
372static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ina2xx_show_value, NULL,
373 INA2XX_SHUNT_VOLTAGE);
374
375/* bus voltage */
376static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ina2xx_show_value, NULL,
377 INA2XX_BUS_VOLTAGE);
378
379/* calculated current */
380static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ina2xx_show_value, NULL,
381 INA2XX_CURRENT);
382
383/* calculated power */
384static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, ina2xx_show_value, NULL,
385 INA2XX_POWER);
386
387/* shunt resistance */
388static SENSOR_DEVICE_ATTR(shunt_resistor, S_IRUGO | S_IWUSR,
389 ina2xx_show_value, ina2xx_set_shunt,
390 INA2XX_CALIBRATION);
391
392/* update interval (ina226 only) */
393static SENSOR_DEVICE_ATTR(update_interval, S_IRUGO | S_IWUSR,
394 ina226_show_interval, ina226_set_interval, 0);
395
396/* pointers to created device attributes */
397static struct attribute *ina2xx_attrs[] = {
398 &sensor_dev_attr_in0_input.dev_attr.attr,
399 &sensor_dev_attr_in1_input.dev_attr.attr,
400 &sensor_dev_attr_curr1_input.dev_attr.attr,
401 &sensor_dev_attr_power1_input.dev_attr.attr,
402 &sensor_dev_attr_shunt_resistor.dev_attr.attr,
403 NULL,
404};
405
406static const struct attribute_group ina2xx_group = {
407 .attrs = ina2xx_attrs,
408};
409
410static struct attribute *ina226_attrs[] = {
411 &sensor_dev_attr_update_interval.dev_attr.attr,
412 NULL,
413};
414
415static const struct attribute_group ina226_group = {
416 .attrs = ina226_attrs,
417};
418
419static int ina2xx_probe(struct i2c_client *client,
420 const struct i2c_device_id *id)
421{
422 struct device *dev = &client->dev;
423 struct ina2xx_data *data;
424 struct device *hwmon_dev;
425 u32 val;
426 int ret, group = 0;
427
428 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
429 if (!data)
430 return -ENOMEM;
431
432 /* set the device type */
433 data->config = &ina2xx_config[id->driver_data];
434
435 if (of_property_read_u32(dev->of_node, "shunt-resistor", &val) < 0) {
436 struct ina2xx_platform_data *pdata = dev_get_platdata(dev);
437
438 if (pdata)
439 val = pdata->shunt_uohms;
440 else
441 val = INA2XX_RSHUNT_DEFAULT;
442 }
443
444 if (val <= 0 || val > data->config->calibration_factor)
445 return -ENODEV;
446
447 data->rshunt = val;
448
449 ina2xx_regmap_config.max_register = data->config->registers;
450
451 data->regmap = devm_regmap_init_i2c(client, &ina2xx_regmap_config);
452 if (IS_ERR(data->regmap)) {
453 dev_err(dev, "failed to allocate register map\n");
454 return PTR_ERR(data->regmap);
455 }
456
457 ret = ina2xx_init(data);
458 if (ret < 0) {
459 dev_err(dev, "error configuring the device: %d\n", ret);
460 return -ENODEV;
461 }
462
463 mutex_init(&data->config_lock);
464
465 data->groups[group++] = &ina2xx_group;
466 if (id->driver_data == ina226)
467 data->groups[group++] = &ina226_group;
468
469 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
470 data, data->groups);
471 if (IS_ERR(hwmon_dev))
472 return PTR_ERR(hwmon_dev);
473
474 dev_info(dev, "power monitor %s (Rshunt = %li uOhm)\n",
475 id->name, data->rshunt);
476
477 return 0;
478}
479
480static const struct i2c_device_id ina2xx_id[] = {
481 { "ina219", ina219 },
482 { "ina220", ina219 },
483 { "ina226", ina226 },
484 { "ina230", ina226 },
485 { "ina231", ina226 },
486 { }
487};
488MODULE_DEVICE_TABLE(i2c, ina2xx_id);
489
490static struct i2c_driver ina2xx_driver = {
491 .driver = {
492 .name = "ina2xx",
493 },
494 .probe = ina2xx_probe,
495 .id_table = ina2xx_id,
496};
497
498module_i2c_driver(ina2xx_driver);
499
500MODULE_AUTHOR("Lothar Felten <l-felten@ti.com>");
501MODULE_DESCRIPTION("ina2xx driver");
502MODULE_LICENSE("GPL");