2 * Driver for the Texas Instruments / Burr Brown INA209
3 * Bidirectional Current/Power Monitor
5 * Copyright (C) 2012 Guenter Roeck <linux@roeck-us.net>
7 * Derived from Ira W. Snyder's original driver submission
8 * Copyright (C) 2008 Paul Hays <Paul.Hays@cattail.ca>
9 * Copyright (C) 2008-2009 Ira W. Snyder <iws@ovro.caltech.edu>
11 * Aligned with ina2xx driver
12 * Copyright (C) 2012 Lothar Felten <l-felten@ti.com>
13 * Thanks to Jan Volkering
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; version 2 of the License.
20 * http://www.ti.com/lit/gpn/ina209
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/err.h>
27 #include <linux/slab.h>
28 #include <linux/bug.h>
29 #include <linux/i2c.h>
30 #include <linux/hwmon.h>
31 #include <linux/hwmon-sysfs.h>
33 #include <linux/platform_data/ina2xx.h>
35 /* register definitions */
36 #define INA209_CONFIGURATION 0x00
37 #define INA209_STATUS 0x01
38 #define INA209_STATUS_MASK 0x02
39 #define INA209_SHUNT_VOLTAGE 0x03
40 #define INA209_BUS_VOLTAGE 0x04
41 #define INA209_POWER 0x05
42 #define INA209_CURRENT 0x06
43 #define INA209_SHUNT_VOLTAGE_POS_PEAK 0x07
44 #define INA209_SHUNT_VOLTAGE_NEG_PEAK 0x08
45 #define INA209_BUS_VOLTAGE_MAX_PEAK 0x09
46 #define INA209_BUS_VOLTAGE_MIN_PEAK 0x0a
47 #define INA209_POWER_PEAK 0x0b
48 #define INA209_SHUNT_VOLTAGE_POS_WARN 0x0c
49 #define INA209_SHUNT_VOLTAGE_NEG_WARN 0x0d
50 #define INA209_POWER_WARN 0x0e
51 #define INA209_BUS_VOLTAGE_OVER_WARN 0x0f
52 #define INA209_BUS_VOLTAGE_UNDER_WARN 0x10
53 #define INA209_POWER_OVER_LIMIT 0x11
54 #define INA209_BUS_VOLTAGE_OVER_LIMIT 0x12
55 #define INA209_BUS_VOLTAGE_UNDER_LIMIT 0x13
56 #define INA209_CRITICAL_DAC_POS 0x14
57 #define INA209_CRITICAL_DAC_NEG 0x15
58 #define INA209_CALIBRATION 0x16
60 #define INA209_REGISTERS 0x17
62 #define INA209_CONFIG_DEFAULT 0x3c47 /* PGA=8, full range */
63 #define INA209_SHUNT_DEFAULT 10000 /* uOhm */
66 struct i2c_client *client;
68 struct mutex update_lock;
70 unsigned long last_updated; /* in jiffies */
72 u16 regs[INA209_REGISTERS]; /* All chip registers */
74 u16 config_orig; /* Original configuration */
75 u16 calibration_orig; /* Original calibration */
79 static struct ina209_data *ina209_update_device(struct device *dev)
81 struct ina209_data *data = dev_get_drvdata(dev);
82 struct i2c_client *client = data->client;
83 struct ina209_data *ret = data;
87 mutex_lock(&data->update_lock);
90 time_after(jiffies, data->last_updated + data->update_interval)) {
91 for (i = 0; i < ARRAY_SIZE(data->regs); i++) {
92 val = i2c_smbus_read_word_swapped(client, i);
99 data->last_updated = jiffies;
103 mutex_unlock(&data->update_lock);
108 * Read a value from a device register and convert it to the
109 * appropriate sysfs units
111 static long ina209_from_reg(const u8 reg, const u16 val)
114 case INA209_SHUNT_VOLTAGE:
115 case INA209_SHUNT_VOLTAGE_POS_PEAK:
116 case INA209_SHUNT_VOLTAGE_NEG_PEAK:
117 case INA209_SHUNT_VOLTAGE_POS_WARN:
118 case INA209_SHUNT_VOLTAGE_NEG_WARN:
119 /* LSB=10 uV. Convert to mV. */
120 return DIV_ROUND_CLOSEST((s16)val, 100);
122 case INA209_BUS_VOLTAGE:
123 case INA209_BUS_VOLTAGE_MAX_PEAK:
124 case INA209_BUS_VOLTAGE_MIN_PEAK:
125 case INA209_BUS_VOLTAGE_OVER_WARN:
126 case INA209_BUS_VOLTAGE_UNDER_WARN:
127 case INA209_BUS_VOLTAGE_OVER_LIMIT:
128 case INA209_BUS_VOLTAGE_UNDER_LIMIT:
129 /* LSB=4 mV, last 3 bits unused */
130 return (val >> 3) * 4;
132 case INA209_CRITICAL_DAC_POS:
133 /* LSB=1 mV, in the upper 8 bits */
136 case INA209_CRITICAL_DAC_NEG:
137 /* LSB=1 mV, in the upper 8 bits */
138 return -1 * (val >> 8);
141 case INA209_POWER_PEAK:
142 case INA209_POWER_WARN:
143 case INA209_POWER_OVER_LIMIT:
144 /* LSB=20 mW. Convert to uW */
145 return val * 20 * 1000L;
148 /* LSB=1 mA (selected). Is in mA */
152 /* programmer goofed */
158 * Take a value and convert it to register format, clamping the value
159 * to the appropriate range.
161 static int ina209_to_reg(u8 reg, u16 old, long val)
164 case INA209_SHUNT_VOLTAGE_POS_WARN:
165 case INA209_SHUNT_VOLTAGE_NEG_WARN:
166 /* Limit to +- 320 mV, 10 uV LSB */
167 return clamp_val(val, -320, 320) * 100;
169 case INA209_BUS_VOLTAGE_OVER_WARN:
170 case INA209_BUS_VOLTAGE_UNDER_WARN:
171 case INA209_BUS_VOLTAGE_OVER_LIMIT:
172 case INA209_BUS_VOLTAGE_UNDER_LIMIT:
174 * Limit to 0-32000 mV, 4 mV LSB
176 * The last three bits aren't part of the value, but we'll
177 * preserve them in their original state.
179 return (DIV_ROUND_CLOSEST(clamp_val(val, 0, 32000), 4) << 3)
182 case INA209_CRITICAL_DAC_NEG:
184 * Limit to -255-0 mV, 1 mV LSB
185 * Convert the value to a positive value for the register
187 * The value lives in the top 8 bits only, be careful
188 * and keep original value of other bits.
190 return (clamp_val(-val, 0, 255) << 8) | (old & 0xff);
192 case INA209_CRITICAL_DAC_POS:
194 * Limit to 0-255 mV, 1 mV LSB
196 * The value lives in the top 8 bits only, be careful
197 * and keep original value of other bits.
199 return (clamp_val(val, 0, 255) << 8) | (old & 0xff);
201 case INA209_POWER_WARN:
202 case INA209_POWER_OVER_LIMIT:
204 return DIV_ROUND_CLOSEST(val, 20 * 1000);
207 /* Other registers are read-only, return access error */
211 static int ina209_interval_from_reg(u16 reg)
213 return 68 >> (15 - ((reg >> 3) & 0x0f));
216 static u16 ina209_reg_from_interval(u16 config, long interval)
224 for (i = 34 + 34 / 2; i; i >>= 1) {
230 return (config & 0xf807) | (adc << 3) | (adc << 7);
233 static ssize_t ina209_interval_store(struct device *dev,
234 struct device_attribute *da,
235 const char *buf, size_t count)
237 struct ina209_data *data = ina209_update_device(dev);
243 return PTR_ERR(data);
245 ret = kstrtol(buf, 10, &val);
249 mutex_lock(&data->update_lock);
250 regval = ina209_reg_from_interval(data->regs[INA209_CONFIGURATION],
252 i2c_smbus_write_word_swapped(data->client, INA209_CONFIGURATION,
254 data->regs[INA209_CONFIGURATION] = regval;
255 data->update_interval = ina209_interval_from_reg(regval);
256 mutex_unlock(&data->update_lock);
260 static ssize_t ina209_interval_show(struct device *dev,
261 struct device_attribute *da, char *buf)
263 struct ina209_data *data = dev_get_drvdata(dev);
265 return snprintf(buf, PAGE_SIZE, "%d\n", data->update_interval);
269 * History is reset by writing 1 into bit 0 of the respective peak register.
270 * Since more than one peak register may be affected by the scope of a
271 * reset_history attribute write, use a bit mask in attr->index to identify
272 * which registers are affected.
274 static u16 ina209_reset_history_regs[] = {
275 INA209_SHUNT_VOLTAGE_POS_PEAK,
276 INA209_SHUNT_VOLTAGE_NEG_PEAK,
277 INA209_BUS_VOLTAGE_MAX_PEAK,
278 INA209_BUS_VOLTAGE_MIN_PEAK,
282 static ssize_t ina209_history_store(struct device *dev,
283 struct device_attribute *da,
284 const char *buf, size_t count)
286 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
287 struct ina209_data *data = dev_get_drvdata(dev);
288 struct i2c_client *client = data->client;
289 u32 mask = attr->index;
293 ret = kstrtol(buf, 10, &val);
297 mutex_lock(&data->update_lock);
298 for (i = 0; i < ARRAY_SIZE(ina209_reset_history_regs); i++) {
300 i2c_smbus_write_word_swapped(client,
301 ina209_reset_history_regs[i], 1);
304 mutex_unlock(&data->update_lock);
308 static ssize_t ina209_value_store(struct device *dev,
309 struct device_attribute *da,
310 const char *buf, size_t count)
312 struct ina209_data *data = ina209_update_device(dev);
313 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
314 int reg = attr->index;
319 return PTR_ERR(data);
321 ret = kstrtol(buf, 10, &val);
325 mutex_lock(&data->update_lock);
326 ret = ina209_to_reg(reg, data->regs[reg], val);
331 i2c_smbus_write_word_swapped(data->client, reg, ret);
332 data->regs[reg] = ret;
334 mutex_unlock(&data->update_lock);
338 static ssize_t ina209_value_show(struct device *dev,
339 struct device_attribute *da, char *buf)
341 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
342 struct ina209_data *data = ina209_update_device(dev);
346 return PTR_ERR(data);
348 val = ina209_from_reg(attr->index, data->regs[attr->index]);
349 return snprintf(buf, PAGE_SIZE, "%ld\n", val);
352 static ssize_t ina209_alarm_show(struct device *dev,
353 struct device_attribute *da, char *buf)
355 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
356 struct ina209_data *data = ina209_update_device(dev);
357 const unsigned int mask = attr->index;
361 return PTR_ERR(data);
363 status = data->regs[INA209_STATUS];
366 * All alarms are in the INA209_STATUS register. To avoid a long
367 * switch statement, the mask is passed in attr->index
369 return snprintf(buf, PAGE_SIZE, "%u\n", !!(status & mask));
372 /* Shunt voltage, history, limits, alarms */
373 static SENSOR_DEVICE_ATTR_RO(in0_input, ina209_value, INA209_SHUNT_VOLTAGE);
374 static SENSOR_DEVICE_ATTR_RO(in0_input_highest, ina209_value,
375 INA209_SHUNT_VOLTAGE_POS_PEAK);
376 static SENSOR_DEVICE_ATTR_RO(in0_input_lowest, ina209_value,
377 INA209_SHUNT_VOLTAGE_NEG_PEAK);
378 static SENSOR_DEVICE_ATTR_WO(in0_reset_history, ina209_history,
379 (1 << 0) | (1 << 1));
380 static SENSOR_DEVICE_ATTR_RW(in0_max, ina209_value,
381 INA209_SHUNT_VOLTAGE_POS_WARN);
382 static SENSOR_DEVICE_ATTR_RW(in0_min, ina209_value,
383 INA209_SHUNT_VOLTAGE_NEG_WARN);
384 static SENSOR_DEVICE_ATTR_RW(in0_crit_max, ina209_value,
385 INA209_CRITICAL_DAC_POS);
386 static SENSOR_DEVICE_ATTR_RW(in0_crit_min, ina209_value,
387 INA209_CRITICAL_DAC_NEG);
389 static SENSOR_DEVICE_ATTR_RO(in0_min_alarm, ina209_alarm, 1 << 11);
390 static SENSOR_DEVICE_ATTR_RO(in0_max_alarm, ina209_alarm, 1 << 12);
391 static SENSOR_DEVICE_ATTR_RO(in0_crit_min_alarm, ina209_alarm, 1 << 6);
392 static SENSOR_DEVICE_ATTR_RO(in0_crit_max_alarm, ina209_alarm, 1 << 7);
394 /* Bus voltage, history, limits, alarms */
395 static SENSOR_DEVICE_ATTR_RO(in1_input, ina209_value, INA209_BUS_VOLTAGE);
396 static SENSOR_DEVICE_ATTR_RO(in1_input_highest, ina209_value,
397 INA209_BUS_VOLTAGE_MAX_PEAK);
398 static SENSOR_DEVICE_ATTR_RO(in1_input_lowest, ina209_value,
399 INA209_BUS_VOLTAGE_MIN_PEAK);
400 static SENSOR_DEVICE_ATTR_WO(in1_reset_history, ina209_history,
401 (1 << 2) | (1 << 3));
402 static SENSOR_DEVICE_ATTR_RW(in1_max, ina209_value,
403 INA209_BUS_VOLTAGE_OVER_WARN);
404 static SENSOR_DEVICE_ATTR_RW(in1_min, ina209_value,
405 INA209_BUS_VOLTAGE_UNDER_WARN);
406 static SENSOR_DEVICE_ATTR_RW(in1_crit_max, ina209_value,
407 INA209_BUS_VOLTAGE_OVER_LIMIT);
408 static SENSOR_DEVICE_ATTR_RW(in1_crit_min, ina209_value,
409 INA209_BUS_VOLTAGE_UNDER_LIMIT);
411 static SENSOR_DEVICE_ATTR_RO(in1_min_alarm, ina209_alarm, 1 << 14);
412 static SENSOR_DEVICE_ATTR_RO(in1_max_alarm, ina209_alarm, 1 << 15);
413 static SENSOR_DEVICE_ATTR_RO(in1_crit_min_alarm, ina209_alarm, 1 << 9);
414 static SENSOR_DEVICE_ATTR_RO(in1_crit_max_alarm, ina209_alarm, 1 << 10);
417 static SENSOR_DEVICE_ATTR_RO(power1_input, ina209_value, INA209_POWER);
418 static SENSOR_DEVICE_ATTR_RO(power1_input_highest, ina209_value,
420 static SENSOR_DEVICE_ATTR_WO(power1_reset_history, ina209_history, 1 << 4);
421 static SENSOR_DEVICE_ATTR_RW(power1_max, ina209_value, INA209_POWER_WARN);
422 static SENSOR_DEVICE_ATTR_RW(power1_crit, ina209_value,
423 INA209_POWER_OVER_LIMIT);
425 static SENSOR_DEVICE_ATTR_RO(power1_max_alarm, ina209_alarm, 1 << 13);
426 static SENSOR_DEVICE_ATTR_RO(power1_crit_alarm, ina209_alarm, 1 << 8);
429 static SENSOR_DEVICE_ATTR_RO(curr1_input, ina209_value, INA209_CURRENT);
431 static SENSOR_DEVICE_ATTR_RW(update_interval, ina209_interval, 0);
434 * Finally, construct an array of pointers to members of the above objects,
435 * as required for sysfs_create_group()
437 static struct attribute *ina209_attrs[] = {
438 &sensor_dev_attr_in0_input.dev_attr.attr,
439 &sensor_dev_attr_in0_input_highest.dev_attr.attr,
440 &sensor_dev_attr_in0_input_lowest.dev_attr.attr,
441 &sensor_dev_attr_in0_reset_history.dev_attr.attr,
442 &sensor_dev_attr_in0_max.dev_attr.attr,
443 &sensor_dev_attr_in0_min.dev_attr.attr,
444 &sensor_dev_attr_in0_crit_max.dev_attr.attr,
445 &sensor_dev_attr_in0_crit_min.dev_attr.attr,
446 &sensor_dev_attr_in0_max_alarm.dev_attr.attr,
447 &sensor_dev_attr_in0_min_alarm.dev_attr.attr,
448 &sensor_dev_attr_in0_crit_max_alarm.dev_attr.attr,
449 &sensor_dev_attr_in0_crit_min_alarm.dev_attr.attr,
451 &sensor_dev_attr_in1_input.dev_attr.attr,
452 &sensor_dev_attr_in1_input_highest.dev_attr.attr,
453 &sensor_dev_attr_in1_input_lowest.dev_attr.attr,
454 &sensor_dev_attr_in1_reset_history.dev_attr.attr,
455 &sensor_dev_attr_in1_max.dev_attr.attr,
456 &sensor_dev_attr_in1_min.dev_attr.attr,
457 &sensor_dev_attr_in1_crit_max.dev_attr.attr,
458 &sensor_dev_attr_in1_crit_min.dev_attr.attr,
459 &sensor_dev_attr_in1_max_alarm.dev_attr.attr,
460 &sensor_dev_attr_in1_min_alarm.dev_attr.attr,
461 &sensor_dev_attr_in1_crit_max_alarm.dev_attr.attr,
462 &sensor_dev_attr_in1_crit_min_alarm.dev_attr.attr,
464 &sensor_dev_attr_power1_input.dev_attr.attr,
465 &sensor_dev_attr_power1_input_highest.dev_attr.attr,
466 &sensor_dev_attr_power1_reset_history.dev_attr.attr,
467 &sensor_dev_attr_power1_max.dev_attr.attr,
468 &sensor_dev_attr_power1_crit.dev_attr.attr,
469 &sensor_dev_attr_power1_max_alarm.dev_attr.attr,
470 &sensor_dev_attr_power1_crit_alarm.dev_attr.attr,
472 &sensor_dev_attr_curr1_input.dev_attr.attr,
474 &sensor_dev_attr_update_interval.dev_attr.attr,
478 ATTRIBUTE_GROUPS(ina209);
480 static void ina209_restore_conf(struct i2c_client *client,
481 struct ina209_data *data)
483 /* Restore initial configuration */
484 i2c_smbus_write_word_swapped(client, INA209_CONFIGURATION,
486 i2c_smbus_write_word_swapped(client, INA209_CALIBRATION,
487 data->calibration_orig);
490 static int ina209_init_client(struct i2c_client *client,
491 struct ina209_data *data)
493 struct ina2xx_platform_data *pdata = dev_get_platdata(&client->dev);
497 reg = i2c_smbus_read_word_swapped(client, INA209_CALIBRATION);
500 data->calibration_orig = reg;
502 reg = i2c_smbus_read_word_swapped(client, INA209_CONFIGURATION);
505 data->config_orig = reg;
508 if (pdata->shunt_uohms <= 0)
510 shunt = pdata->shunt_uohms;
511 } else if (!of_property_read_u32(client->dev.of_node, "shunt-resistor",
516 shunt = data->calibration_orig ?
517 40960000 / data->calibration_orig : INA209_SHUNT_DEFAULT;
520 i2c_smbus_write_word_swapped(client, INA209_CONFIGURATION,
521 INA209_CONFIG_DEFAULT);
522 data->update_interval = ina209_interval_from_reg(INA209_CONFIG_DEFAULT);
525 * Calibrate current LSB to 1mA. Shunt is in uOhms.
526 * See equation 13 in datasheet.
528 i2c_smbus_write_word_swapped(client, INA209_CALIBRATION,
529 clamp_val(40960000 / shunt, 1, 65535));
531 /* Clear status register */
532 i2c_smbus_read_word_swapped(client, INA209_STATUS);
537 static int ina209_probe(struct i2c_client *client,
538 const struct i2c_device_id *id)
540 struct i2c_adapter *adapter = client->adapter;
541 struct ina209_data *data;
542 struct device *hwmon_dev;
545 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
548 data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
552 i2c_set_clientdata(client, data);
553 data->client = client;
554 mutex_init(&data->update_lock);
556 ret = ina209_init_client(client, data);
560 hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
562 data, ina209_groups);
563 if (IS_ERR(hwmon_dev)) {
564 ret = PTR_ERR(hwmon_dev);
565 goto out_restore_conf;
571 ina209_restore_conf(client, data);
575 static int ina209_remove(struct i2c_client *client)
577 struct ina209_data *data = i2c_get_clientdata(client);
579 ina209_restore_conf(client, data);
584 static const struct i2c_device_id ina209_id[] = {
588 MODULE_DEVICE_TABLE(i2c, ina209_id);
590 static const struct of_device_id __maybe_unused ina209_of_match[] = {
591 { .compatible = "ti,ina209" },
594 MODULE_DEVICE_TABLE(of, ina209_of_match);
596 /* This is the driver that will be inserted */
597 static struct i2c_driver ina209_driver = {
598 .class = I2C_CLASS_HWMON,
601 .of_match_table = of_match_ptr(ina209_of_match),
603 .probe = ina209_probe,
604 .remove = ina209_remove,
605 .id_table = ina209_id,
608 module_i2c_driver(ina209_driver);
610 MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>, Paul Hays <Paul.Hays@cattail.ca>, Guenter Roeck <linux@roeck-us.net>");
611 MODULE_DESCRIPTION("INA209 driver");
612 MODULE_LICENSE("GPL");