1 // SPDX-License-Identifier: GPL-2.0-only
3 * Driver for Texas Instruments INA219, INA226 power monitor chips
6 * Zero Drift Bi-Directional Current/Power Monitor with I2C Interface
7 * Datasheet: https://www.ti.com/product/ina219
10 * Bi-Directional Current/Power Monitor with I2C Interface
11 * Datasheet: https://www.ti.com/product/ina220
14 * Bi-Directional Current/Power Monitor with I2C Interface
15 * Datasheet: https://www.ti.com/product/ina226
18 * Bi-directional Current/Power Monitor with I2C Interface
19 * Datasheet: https://www.ti.com/product/ina230
21 * Copyright (C) 2012 Lothar Felten <lothar.felten@gmail.com>
22 * Thanks to Jan Volkering
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>
36 #include <linux/delay.h>
37 #include <linux/util_macros.h>
38 #include <linux/regmap.h>
40 #include <linux/platform_data/ina2xx.h>
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
50 /* INA226 register definitions */
51 #define INA226_MASK_ENABLE 0x06
52 #define INA226_ALERT_LIMIT 0x07
53 #define INA226_DIE_ID 0xFF
56 #define INA219_REGISTERS 6
57 #define INA226_REGISTERS 8
59 #define INA2XX_MAX_REGISTERS 8
61 /* settings - depend on use case */
62 #define INA219_CONFIG_DEFAULT 0x399F /* PGA=8 */
63 #define INA226_CONFIG_DEFAULT 0x4527 /* averages=16 */
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 */
69 #define INA2XX_RSHUNT_DEFAULT 10000
71 /* bit mask for reading the averaging setting in the configuration register */
72 #define INA226_AVG_RD_MASK 0x0E00
74 #define INA226_READ_AVG(reg) (((reg) & INA226_AVG_RD_MASK) >> 9)
75 #define INA226_SHIFT_AVG(val) ((val) << 9)
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
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)
88 /* common attrs, ina226 attrs and NULL */
89 #define INA2XX_MAX_ATTRIBUTE_GROUPS 3
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.
95 #define INA226_TOTAL_CONV_TIME_DEFAULT 2200
97 static struct regmap_config ina2xx_regmap_config
= {
102 enum ina2xx_ids
{ ina219
, ina226
};
104 struct ina2xx_config
{
106 int calibration_value
;
109 int bus_voltage_shift
;
110 int bus_voltage_lsb
; /* uV */
111 int power_lsb_factor
;
115 const struct ina2xx_config
*config
;
120 struct mutex config_lock
;
121 struct regmap
*regmap
;
123 const struct attribute_group
*groups
[INA2XX_MAX_ATTRIBUTE_GROUPS
];
126 static const struct ina2xx_config ina2xx_config
[] = {
128 .config_default
= INA219_CONFIG_DEFAULT
,
129 .calibration_value
= 4096,
130 .registers
= INA219_REGISTERS
,
132 .bus_voltage_shift
= 3,
133 .bus_voltage_lsb
= 4000,
134 .power_lsb_factor
= 20,
137 .config_default
= INA226_CONFIG_DEFAULT
,
138 .calibration_value
= 2048,
139 .registers
= INA226_REGISTERS
,
141 .bus_voltage_shift
= 0,
142 .bus_voltage_lsb
= 1250,
143 .power_lsb_factor
= 25,
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.
153 static const int ina226_avg_tab
[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
155 static int ina226_reg_to_interval(u16 config
)
157 int avg
= ina226_avg_tab
[INA226_READ_AVG(config
)];
160 * Multiply the total conversion time by the number of averages.
161 * Return the result in milliseconds.
163 return DIV_ROUND_CLOSEST(avg
* INA226_TOTAL_CONV_TIME_DEFAULT
, 1000);
167 * Return the new, shifted AVG field value of CONFIG register,
168 * to use with regmap_update_bits
170 static u16
ina226_interval_to_reg(int interval
)
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
));
179 return INA226_SHIFT_AVG(avg_bits
);
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.
188 static int ina2xx_calibrate(struct ina2xx_data
*data
)
190 return regmap_write(data
->regmap
, INA2XX_CALIBRATION
,
191 data
->config
->calibration_value
);
195 * Initialize the configuration and calibration registers.
197 static int ina2xx_init(struct ina2xx_data
*data
)
199 int ret
= regmap_write(data
->regmap
, INA2XX_CONFIG
,
200 data
->config
->config_default
);
204 return ina2xx_calibrate(data
);
207 static int ina2xx_read_reg(struct device
*dev
, int reg
, unsigned int *regval
)
209 struct ina2xx_data
*data
= dev_get_drvdata(dev
);
212 dev_dbg(dev
, "Starting register %d read\n", reg
);
214 for (retry
= 5; retry
; retry
--) {
216 ret
= regmap_read(data
->regmap
, reg
, regval
);
220 dev_dbg(dev
, "read %d, val = 0x%04x\n", reg
, *regval
);
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.
233 ret
= regmap_read(data
->regmap
, INA2XX_CALIBRATION
,
239 dev_warn(dev
, "chip not calibrated, reinitializing\n");
241 ret
= ina2xx_init(data
);
245 * Let's make sure the power and current
246 * registers have been updated before trying
249 msleep(INA2XX_MAX_DELAY
);
257 * If we're here then although all write operations succeeded, the
258 * chip still returns 0 in the calibration register. Nothing more we
261 dev_err(dev
, "unable to reinitialize the chip\n");
265 static int ina2xx_get_value(struct ina2xx_data
*data
, u8 reg
,
271 case INA2XX_SHUNT_VOLTAGE
:
272 /* signed register */
273 val
= DIV_ROUND_CLOSEST((s16
)regval
, data
->config
->shunt_div
);
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);
281 val
= regval
* data
->power_lsb_uW
;
284 /* signed register, result in mA */
285 val
= (s16
)regval
* data
->current_lsb_uA
;
286 val
= DIV_ROUND_CLOSEST(val
, 1000);
288 case INA2XX_CALIBRATION
:
292 /* programmer goofed */
301 static ssize_t
ina2xx_value_show(struct device
*dev
,
302 struct device_attribute
*da
, char *buf
)
304 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(da
);
305 struct ina2xx_data
*data
= dev_get_drvdata(dev
);
308 int err
= ina2xx_read_reg(dev
, attr
->index
, ®val
);
313 return snprintf(buf
, PAGE_SIZE
, "%d\n",
314 ina2xx_get_value(data
, attr
->index
, regval
));
317 static int ina226_reg_to_alert(struct ina2xx_data
*data
, u8 bit
, u16 regval
)
322 case INA226_SHUNT_OVER_VOLTAGE_BIT
:
323 case INA226_SHUNT_UNDER_VOLTAGE_BIT
:
324 reg
= INA2XX_SHUNT_VOLTAGE
;
326 case INA226_BUS_OVER_VOLTAGE_BIT
:
327 case INA226_BUS_UNDER_VOLTAGE_BIT
:
328 reg
= INA2XX_BUS_VOLTAGE
;
330 case INA226_POWER_OVER_LIMIT_BIT
:
334 /* programmer goofed */
339 return ina2xx_get_value(data
, reg
, regval
);
343 * Turns alert limit values into register values.
344 * Opposite of the formula in ina2xx_get_value().
346 static s16
ina226_alert_to_reg(struct ina2xx_data
*data
, u8 bit
, int val
)
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
);
362 /* programmer goofed */
368 static ssize_t
ina226_alert_show(struct device
*dev
,
369 struct device_attribute
*da
, char *buf
)
371 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(da
);
372 struct ina2xx_data
*data
= dev_get_drvdata(dev
);
377 mutex_lock(&data
->config_lock
);
378 ret
= regmap_read(data
->regmap
, INA226_MASK_ENABLE
, ®val
);
382 if (regval
& BIT(attr
->index
)) {
383 ret
= regmap_read(data
->regmap
, INA226_ALERT_LIMIT
, ®val
);
386 val
= ina226_reg_to_alert(data
, attr
->index
, regval
);
389 ret
= snprintf(buf
, PAGE_SIZE
, "%d\n", val
);
391 mutex_unlock(&data
->config_lock
);
395 static ssize_t
ina226_alert_store(struct device
*dev
,
396 struct device_attribute
*da
,
397 const char *buf
, size_t count
)
399 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(da
);
400 struct ina2xx_data
*data
= dev_get_drvdata(dev
);
404 ret
= kstrtoul(buf
, 10, &val
);
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.
413 mutex_lock(&data
->config_lock
);
414 ret
= regmap_update_bits(data
->regmap
, INA226_MASK_ENABLE
,
415 INA226_ALERT_CONFIG_MASK
, 0);
419 ret
= regmap_write(data
->regmap
, INA226_ALERT_LIMIT
,
420 ina226_alert_to_reg(data
, attr
->index
, val
));
425 ret
= regmap_update_bits(data
->regmap
, INA226_MASK_ENABLE
,
426 INA226_ALERT_CONFIG_MASK
,
434 mutex_unlock(&data
->config_lock
);
438 static ssize_t
ina226_alarm_show(struct device
*dev
,
439 struct device_attribute
*da
, char *buf
)
441 struct sensor_device_attribute
*attr
= to_sensor_dev_attr(da
);
442 struct ina2xx_data
*data
= dev_get_drvdata(dev
);
447 ret
= regmap_read(data
->regmap
, INA226_MASK_ENABLE
, ®val
);
451 alarm
= (regval
& BIT(attr
->index
)) &&
452 (regval
& INA226_ALERT_FUNCTION_FLAG
);
453 return snprintf(buf
, PAGE_SIZE
, "%d\n", alarm
);
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
462 static int ina2xx_set_shunt(struct ina2xx_data
*data
, long val
)
464 unsigned int dividend
= DIV_ROUND_CLOSEST(1000000000,
465 data
->config
->shunt_div
);
466 if (val
<= 0 || val
> dividend
)
469 mutex_lock(&data
->config_lock
);
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
);
479 static ssize_t
ina2xx_shunt_show(struct device
*dev
,
480 struct device_attribute
*da
, char *buf
)
482 struct ina2xx_data
*data
= dev_get_drvdata(dev
);
484 return snprintf(buf
, PAGE_SIZE
, "%li\n", data
->rshunt
);
487 static ssize_t
ina2xx_shunt_store(struct device
*dev
,
488 struct device_attribute
*da
,
489 const char *buf
, size_t count
)
493 struct ina2xx_data
*data
= dev_get_drvdata(dev
);
495 status
= kstrtoul(buf
, 10, &val
);
499 status
= ina2xx_set_shunt(data
, val
);
505 static ssize_t
ina226_interval_store(struct device
*dev
,
506 struct device_attribute
*da
,
507 const char *buf
, size_t count
)
509 struct ina2xx_data
*data
= dev_get_drvdata(dev
);
513 status
= kstrtoul(buf
, 10, &val
);
517 if (val
> INT_MAX
|| val
== 0)
520 status
= regmap_update_bits(data
->regmap
, INA2XX_CONFIG
,
522 ina226_interval_to_reg(val
));
529 static ssize_t
ina226_interval_show(struct device
*dev
,
530 struct device_attribute
*da
, char *buf
)
532 struct ina2xx_data
*data
= dev_get_drvdata(dev
);
536 status
= regmap_read(data
->regmap
, INA2XX_CONFIG
, ®val
);
540 return snprintf(buf
, PAGE_SIZE
, "%d\n", ina226_reg_to_interval(regval
));
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
);
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
);
567 /* calculated current */
568 static SENSOR_DEVICE_ATTR_RO(curr1_input
, ina2xx_value
, INA2XX_CURRENT
);
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
);
578 /* shunt resistance */
579 static SENSOR_DEVICE_ATTR_RW(shunt_resistor
, ina2xx_shunt
, INA2XX_CALIBRATION
);
581 /* update interval (ina226 only) */
582 static SENSOR_DEVICE_ATTR_RW(update_interval
, ina226_interval
, 0);
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
,
594 static const struct attribute_group ina2xx_group
= {
595 .attrs
= ina2xx_attrs
,
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
,
613 static const struct attribute_group ina226_group
= {
614 .attrs
= ina226_attrs
,
617 static const struct i2c_device_id ina2xx_id
[];
619 static int ina2xx_probe(struct i2c_client
*client
)
621 struct device
*dev
= &client
->dev
;
622 struct ina2xx_data
*data
;
623 struct device
*hwmon_dev
;
626 enum ina2xx_ids chip
;
628 if (client
->dev
.of_node
)
629 chip
= (enum ina2xx_ids
)of_device_get_match_data(&client
->dev
);
631 chip
= i2c_match_id(ina2xx_id
, client
)->driver_data
;
633 data
= devm_kzalloc(dev
, sizeof(*data
), GFP_KERNEL
);
637 /* set the device type */
638 data
->config
= &ina2xx_config
[chip
];
639 mutex_init(&data
->config_lock
);
641 if (of_property_read_u32(dev
->of_node
, "shunt-resistor", &val
) < 0) {
642 struct ina2xx_platform_data
*pdata
= dev_get_platdata(dev
);
645 val
= pdata
->shunt_uohms
;
647 val
= INA2XX_RSHUNT_DEFAULT
;
650 ina2xx_set_shunt(data
, val
);
652 ina2xx_regmap_config
.max_register
= data
->config
->registers
;
654 data
->regmap
= devm_regmap_init_i2c(client
, &ina2xx_regmap_config
);
655 if (IS_ERR(data
->regmap
)) {
656 dev_err(dev
, "failed to allocate register map\n");
657 return PTR_ERR(data
->regmap
);
660 ret
= ina2xx_init(data
);
662 dev_err(dev
, "error configuring the device: %d\n", ret
);
666 data
->groups
[group
++] = &ina2xx_group
;
668 data
->groups
[group
++] = &ina226_group
;
670 hwmon_dev
= devm_hwmon_device_register_with_groups(dev
, client
->name
,
672 if (IS_ERR(hwmon_dev
))
673 return PTR_ERR(hwmon_dev
);
675 dev_info(dev
, "power monitor %s (Rshunt = %li uOhm)\n",
676 client
->name
, data
->rshunt
);
681 static const struct i2c_device_id ina2xx_id
[] = {
682 { "ina219", ina219
},
683 { "ina220", ina219
},
684 { "ina226", ina226
},
685 { "ina230", ina226
},
686 { "ina231", ina226
},
689 MODULE_DEVICE_TABLE(i2c
, ina2xx_id
);
691 static const struct of_device_id __maybe_unused ina2xx_of_match
[] = {
693 .compatible
= "ti,ina219",
694 .data
= (void *)ina219
697 .compatible
= "ti,ina220",
698 .data
= (void *)ina219
701 .compatible
= "ti,ina226",
702 .data
= (void *)ina226
705 .compatible
= "ti,ina230",
706 .data
= (void *)ina226
709 .compatible
= "ti,ina231",
710 .data
= (void *)ina226
714 MODULE_DEVICE_TABLE(of
, ina2xx_of_match
);
716 static struct i2c_driver ina2xx_driver
= {
719 .of_match_table
= of_match_ptr(ina2xx_of_match
),
721 .probe_new
= ina2xx_probe
,
722 .id_table
= ina2xx_id
,
725 module_i2c_driver(ina2xx_driver
);
727 MODULE_AUTHOR("Lothar Felten <l-felten@ti.com>");
728 MODULE_DESCRIPTION("ina2xx driver");
729 MODULE_LICENSE("GPL");