1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * INA3221 Triple Current/Voltage Monitor
4 *
5 * Copyright (C) 2016 Texas Instruments Incorporated - https://www.ti.com/
6 * Andrew F. Davis <afd@ti.com>
7 */
8
9#include <linux/debugfs.h>
10#include <linux/hwmon.h>
11#include <linux/hwmon-sysfs.h>
12#include <linux/i2c.h>
13#include <linux/module.h>
14#include <linux/mutex.h>
15#include <linux/of.h>
16#include <linux/pm_runtime.h>
17#include <linux/regmap.h>
18#include <linux/util_macros.h>
19
20#define INA3221_DRIVER_NAME "ina3221"
21
22#define INA3221_CONFIG 0x00
23#define INA3221_SHUNT1 0x01
24#define INA3221_BUS1 0x02
25#define INA3221_SHUNT2 0x03
26#define INA3221_BUS2 0x04
27#define INA3221_SHUNT3 0x05
28#define INA3221_BUS3 0x06
29#define INA3221_CRIT1 0x07
30#define INA3221_WARN1 0x08
31#define INA3221_CRIT2 0x09
32#define INA3221_WARN2 0x0a
33#define INA3221_CRIT3 0x0b
34#define INA3221_WARN3 0x0c
35#define INA3221_SHUNT_SUM 0x0d
36#define INA3221_CRIT_SUM 0x0e
37#define INA3221_MASK_ENABLE 0x0f
38
39#define INA3221_CONFIG_MODE_MASK GENMASK(2, 0)
40#define INA3221_CONFIG_MODE_POWERDOWN 0
41#define INA3221_CONFIG_MODE_SHUNT BIT(0)
42#define INA3221_CONFIG_MODE_BUS BIT(1)
43#define INA3221_CONFIG_MODE_CONTINUOUS BIT(2)
44#define INA3221_CONFIG_VSH_CT_SHIFT 3
45#define INA3221_CONFIG_VSH_CT_MASK GENMASK(5, 3)
46#define INA3221_CONFIG_VSH_CT(x) (((x) & GENMASK(5, 3)) >> 3)
47#define INA3221_CONFIG_VBUS_CT_SHIFT 6
48#define INA3221_CONFIG_VBUS_CT_MASK GENMASK(8, 6)
49#define INA3221_CONFIG_VBUS_CT(x) (((x) & GENMASK(8, 6)) >> 6)
50#define INA3221_CONFIG_AVG_SHIFT 9
51#define INA3221_CONFIG_AVG_MASK GENMASK(11, 9)
52#define INA3221_CONFIG_AVG(x) (((x) & GENMASK(11, 9)) >> 9)
53#define INA3221_CONFIG_CHs_EN_MASK GENMASK(14, 12)
54#define INA3221_CONFIG_CHx_EN(x) BIT(14 - (x))
55
56#define INA3221_MASK_ENABLE_SCC_MASK GENMASK(14, 12)
57
58#define INA3221_CONFIG_DEFAULT 0x7127
59#define INA3221_RSHUNT_DEFAULT 10000
60
61enum ina3221_fields {
62 /* Configuration */
63 F_RST,
64
65 /* Status Flags */
66 F_CVRF,
67
68 /* Warning Flags */
69 F_WF3, F_WF2, F_WF1,
70
71 /* Alert Flags: SF is the summation-alert flag */
72 F_SF, F_CF3, F_CF2, F_CF1,
73
74 /* sentinel */
75 F_MAX_FIELDS
76};
77
78static const struct reg_field ina3221_reg_fields[] = {
79 [F_RST] = REG_FIELD(INA3221_CONFIG, 15, 15),
80
81 [F_CVRF] = REG_FIELD(INA3221_MASK_ENABLE, 0, 0),
82 [F_WF3] = REG_FIELD(INA3221_MASK_ENABLE, 3, 3),
83 [F_WF2] = REG_FIELD(INA3221_MASK_ENABLE, 4, 4),
84 [F_WF1] = REG_FIELD(INA3221_MASK_ENABLE, 5, 5),
85 [F_SF] = REG_FIELD(INA3221_MASK_ENABLE, 6, 6),
86 [F_CF3] = REG_FIELD(INA3221_MASK_ENABLE, 7, 7),
87 [F_CF2] = REG_FIELD(INA3221_MASK_ENABLE, 8, 8),
88 [F_CF1] = REG_FIELD(INA3221_MASK_ENABLE, 9, 9),
89};
90
91enum ina3221_channels {
92 INA3221_CHANNEL1,
93 INA3221_CHANNEL2,
94 INA3221_CHANNEL3,
95 INA3221_NUM_CHANNELS
96};
97
98/**
99 * struct ina3221_input - channel input source specific information
100 * @label: label of channel input source
101 * @shunt_resistor: shunt resistor value of channel input source
102 * @disconnected: connection status of channel input source
103 * @summation_disable: channel summation status of input source
104 */
105struct ina3221_input {
106 const char *label;
107 int shunt_resistor;
108 bool disconnected;
109 bool summation_disable;
110};
111
112/**
113 * struct ina3221_data - device specific information
114 * @pm_dev: Device pointer for pm runtime
115 * @regmap: Register map of the device
116 * @fields: Register fields of the device
117 * @inputs: Array of channel input source specific structures
118 * @lock: mutex lock to serialize sysfs attribute accesses
119 * @debugfs: Pointer to debugfs entry for device
120 * @reg_config: Register value of INA3221_CONFIG
121 * @summation_shunt_resistor: equivalent shunt resistor value for summation
122 * @summation_channel_control: Value written to SCC field in INA3221_MASK_ENABLE
123 * @single_shot: running in single-shot operating mode
124 */
125struct ina3221_data {
126 struct device *pm_dev;
127 struct regmap *regmap;
128 struct regmap_field *fields[F_MAX_FIELDS];
129 struct ina3221_input inputs[INA3221_NUM_CHANNELS];
130 struct mutex lock;
131 struct dentry *debugfs;
132 u32 reg_config;
133 int summation_shunt_resistor;
134 u32 summation_channel_control;
135
136 bool single_shot;
137};
138
139static inline bool ina3221_is_enabled(struct ina3221_data *ina, int channel)
140{
141 /* Summation channel checks shunt resistor values */
142 if (channel > INA3221_CHANNEL3)
143 return ina->summation_shunt_resistor != 0;
144
145 return pm_runtime_active(dev: ina->pm_dev) &&
146 (ina->reg_config & INA3221_CONFIG_CHx_EN(channel));
147}
148
149/*
150 * Helper function to return the resistor value for current summation.
151 *
152 * There is a condition to calculate current summation -- all the shunt
153 * resistor values should be the same, so as to simply fit the formula:
154 * current summation = shunt voltage summation / shunt resistor
155 *
156 * Returns the equivalent shunt resistor value on success or 0 on failure
157 */
158static inline int ina3221_summation_shunt_resistor(struct ina3221_data *ina)
159{
160 struct ina3221_input *input = ina->inputs;
161 int i, shunt_resistor = 0;
162
163 for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
164 if (input[i].disconnected || !input[i].shunt_resistor ||
165 input[i].summation_disable)
166 continue;
167 if (!shunt_resistor) {
168 /* Found the reference shunt resistor value */
169 shunt_resistor = input[i].shunt_resistor;
170 } else {
171 /* No summation if resistor values are different */
172 if (shunt_resistor != input[i].shunt_resistor)
173 return 0;
174 }
175 }
176
177 return shunt_resistor;
178}
179
180/* Lookup table for Bus and Shunt conversion times in usec */
181static const u16 ina3221_conv_time[] = {
182 140, 204, 332, 588, 1100, 2116, 4156, 8244,
183};
184
185/* Lookup table for number of samples using in averaging mode */
186static const int ina3221_avg_samples[] = {
187 1, 4, 16, 64, 128, 256, 512, 1024,
188};
189
190/* Converting update_interval in msec to conversion time in usec */
191static inline u32 ina3221_interval_ms_to_conv_time(u16 config, int interval)
192{
193 u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK);
194 u32 samples_idx = INA3221_CONFIG_AVG(config);
195 u32 samples = ina3221_avg_samples[samples_idx];
196
197 /* Bisect the result to Bus and Shunt conversion times */
198 return DIV_ROUND_CLOSEST(interval * 1000 / 2, channels * samples);
199}
200
201/* Converting CONFIG register value to update_interval in usec */
202static inline u32 ina3221_reg_to_interval_us(u16 config)
203{
204 u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK);
205 u32 vbus_ct_idx = INA3221_CONFIG_VBUS_CT(config);
206 u32 vsh_ct_idx = INA3221_CONFIG_VSH_CT(config);
207 u32 vbus_ct = ina3221_conv_time[vbus_ct_idx];
208 u32 vsh_ct = ina3221_conv_time[vsh_ct_idx];
209
210 /* Calculate total conversion time */
211 return channels * (vbus_ct + vsh_ct);
212}
213
214static inline int ina3221_wait_for_data(struct ina3221_data *ina)
215{
216 u32 wait, cvrf;
217
218 wait = ina3221_reg_to_interval_us(config: ina->reg_config);
219
220 /* Polling the CVRF bit to make sure read data is ready */
221 return regmap_field_read_poll_timeout(ina->fields[F_CVRF],
222 cvrf, cvrf, wait, wait * 2);
223}
224
225static int ina3221_read_value(struct ina3221_data *ina, unsigned int reg,
226 int *val)
227{
228 unsigned int regval;
229 int ret;
230
231 ret = regmap_read(map: ina->regmap, reg, val: &regval);
232 if (ret)
233 return ret;
234
235 /*
236 * Shunt Voltage Sum register has 14-bit value with 1-bit shift
237 * Other Shunt Voltage registers have 12 bits with 3-bit shift
238 */
239 if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM)
240 *val = sign_extend32(value: regval >> 1, index: 14);
241 else
242 *val = sign_extend32(value: regval >> 3, index: 12);
243
244 return 0;
245}
246
247static const u8 ina3221_in_reg[] = {
248 INA3221_BUS1,
249 INA3221_BUS2,
250 INA3221_BUS3,
251 INA3221_SHUNT1,
252 INA3221_SHUNT2,
253 INA3221_SHUNT3,
254 INA3221_SHUNT_SUM,
255};
256
257static int ina3221_read_chip(struct device *dev, u32 attr, long *val)
258{
259 struct ina3221_data *ina = dev_get_drvdata(dev);
260 int regval;
261
262 switch (attr) {
263 case hwmon_chip_samples:
264 regval = INA3221_CONFIG_AVG(ina->reg_config);
265 *val = ina3221_avg_samples[regval];
266 return 0;
267 case hwmon_chip_update_interval:
268 /* Return in msec */
269 *val = ina3221_reg_to_interval_us(config: ina->reg_config);
270 *val = DIV_ROUND_CLOSEST(*val, 1000);
271 return 0;
272 default:
273 return -EOPNOTSUPP;
274 }
275}
276
277static int ina3221_read_in(struct device *dev, u32 attr, int channel, long *val)
278{
279 const bool is_shunt = channel > INA3221_CHANNEL3;
280 struct ina3221_data *ina = dev_get_drvdata(dev);
281 u8 reg = ina3221_in_reg[channel];
282 int regval, ret;
283
284 /*
285 * Translate shunt channel index to sensor channel index except
286 * the 7th channel (6 since being 0-aligned) is for summation.
287 */
288 if (channel != 6)
289 channel %= INA3221_NUM_CHANNELS;
290
291 switch (attr) {
292 case hwmon_in_input:
293 if (!ina3221_is_enabled(ina, channel))
294 return -ENODATA;
295
296 /* Write CONFIG register to trigger a single-shot measurement */
297 if (ina->single_shot) {
298 regmap_write(map: ina->regmap, INA3221_CONFIG,
299 val: ina->reg_config);
300
301 ret = ina3221_wait_for_data(ina);
302 if (ret)
303 return ret;
304 }
305
306 ret = ina3221_read_value(ina, reg, val: &regval);
307 if (ret)
308 return ret;
309
310 /*
311 * Scale of shunt voltage (uV): LSB is 40uV
312 * Scale of bus voltage (mV): LSB is 8mV
313 */
314 *val = regval * (is_shunt ? 40 : 8);
315 return 0;
316 case hwmon_in_enable:
317 *val = ina3221_is_enabled(ina, channel);
318 return 0;
319 default:
320 return -EOPNOTSUPP;
321 }
322}
323
324static const u8 ina3221_curr_reg[][INA3221_NUM_CHANNELS + 1] = {
325 [hwmon_curr_input] = { INA3221_SHUNT1, INA3221_SHUNT2,
326 INA3221_SHUNT3, INA3221_SHUNT_SUM },
327 [hwmon_curr_max] = { INA3221_WARN1, INA3221_WARN2, INA3221_WARN3, 0 },
328 [hwmon_curr_crit] = { INA3221_CRIT1, INA3221_CRIT2,
329 INA3221_CRIT3, INA3221_CRIT_SUM },
330 [hwmon_curr_max_alarm] = { F_WF1, F_WF2, F_WF3, 0 },
331 [hwmon_curr_crit_alarm] = { F_CF1, F_CF2, F_CF3, F_SF },
332};
333
334static int ina3221_read_curr(struct device *dev, u32 attr,
335 int channel, long *val)
336{
337 struct ina3221_data *ina = dev_get_drvdata(dev);
338 struct ina3221_input *input = ina->inputs;
339 u8 reg = ina3221_curr_reg[attr][channel];
340 int resistance_uo, voltage_nv;
341 int regval, ret;
342
343 if (channel > INA3221_CHANNEL3)
344 resistance_uo = ina->summation_shunt_resistor;
345 else
346 resistance_uo = input[channel].shunt_resistor;
347
348 switch (attr) {
349 case hwmon_curr_input:
350 if (!ina3221_is_enabled(ina, channel))
351 return -ENODATA;
352
353 /* Write CONFIG register to trigger a single-shot measurement */
354 if (ina->single_shot) {
355 regmap_write(map: ina->regmap, INA3221_CONFIG,
356 val: ina->reg_config);
357
358 ret = ina3221_wait_for_data(ina);
359 if (ret)
360 return ret;
361 }
362
363 fallthrough;
364 case hwmon_curr_crit:
365 case hwmon_curr_max:
366 if (!resistance_uo)
367 return -ENODATA;
368
369 ret = ina3221_read_value(ina, reg, val: &regval);
370 if (ret)
371 return ret;
372
373 /* Scale of shunt voltage: LSB is 40uV (40000nV) */
374 voltage_nv = regval * 40000;
375 /* Return current in mA */
376 *val = DIV_ROUND_CLOSEST(voltage_nv, resistance_uo);
377 return 0;
378 case hwmon_curr_crit_alarm:
379 case hwmon_curr_max_alarm:
380 /* No actual register read if channel is disabled */
381 if (!ina3221_is_enabled(ina, channel)) {
382 /* Return 0 for alert flags */
383 *val = 0;
384 return 0;
385 }
386 ret = regmap_field_read(field: ina->fields[reg], val: &regval);
387 if (ret)
388 return ret;
389 *val = regval;
390 return 0;
391 default:
392 return -EOPNOTSUPP;
393 }
394}
395
396static int ina3221_write_chip(struct device *dev, u32 attr, long val)
397{
398 struct ina3221_data *ina = dev_get_drvdata(dev);
399 int ret, idx;
400 u32 tmp;
401
402 switch (attr) {
403 case hwmon_chip_samples:
404 idx = find_closest(val, ina3221_avg_samples,
405 ARRAY_SIZE(ina3221_avg_samples));
406
407 tmp = (ina->reg_config & ~INA3221_CONFIG_AVG_MASK) |
408 (idx << INA3221_CONFIG_AVG_SHIFT);
409 ret = regmap_write(map: ina->regmap, INA3221_CONFIG, val: tmp);
410 if (ret)
411 return ret;
412
413 /* Update reg_config accordingly */
414 ina->reg_config = tmp;
415 return 0;
416 case hwmon_chip_update_interval:
417 tmp = ina3221_interval_ms_to_conv_time(config: ina->reg_config, interval: val);
418 idx = find_closest(tmp, ina3221_conv_time,
419 ARRAY_SIZE(ina3221_conv_time));
420
421 /* Update Bus and Shunt voltage conversion times */
422 tmp = INA3221_CONFIG_VBUS_CT_MASK | INA3221_CONFIG_VSH_CT_MASK;
423 tmp = (ina->reg_config & ~tmp) |
424 (idx << INA3221_CONFIG_VBUS_CT_SHIFT) |
425 (idx << INA3221_CONFIG_VSH_CT_SHIFT);
426 ret = regmap_write(map: ina->regmap, INA3221_CONFIG, val: tmp);
427 if (ret)
428 return ret;
429
430 /* Update reg_config accordingly */
431 ina->reg_config = tmp;
432 return 0;
433 default:
434 return -EOPNOTSUPP;
435 }
436}
437
438static int ina3221_write_curr(struct device *dev, u32 attr,
439 int channel, long val)
440{
441 struct ina3221_data *ina = dev_get_drvdata(dev);
442 struct ina3221_input *input = ina->inputs;
443 u8 reg = ina3221_curr_reg[attr][channel];
444 int resistance_uo, current_ma, voltage_uv;
445 int regval;
446
447 if (channel > INA3221_CHANNEL3)
448 resistance_uo = ina->summation_shunt_resistor;
449 else
450 resistance_uo = input[channel].shunt_resistor;
451
452 if (!resistance_uo)
453 return -EOPNOTSUPP;
454
455 /* clamp current */
456 current_ma = clamp_val(val,
457 INT_MIN / resistance_uo,
458 INT_MAX / resistance_uo);
459
460 voltage_uv = DIV_ROUND_CLOSEST(current_ma * resistance_uo, 1000);
461
462 /* clamp voltage */
463 voltage_uv = clamp_val(voltage_uv, -163800, 163800);
464
465 /*
466 * Formula to convert voltage_uv to register value:
467 * regval = (voltage_uv / scale) << shift
468 * Note:
469 * The scale is 40uV for all shunt voltage registers
470 * Shunt Voltage Sum register left-shifts 1 bit
471 * All other Shunt Voltage registers shift 3 bits
472 * Results:
473 * SHUNT_SUM: (1 / 40uV) << 1 = 1 / 20uV
474 * SHUNT[1-3]: (1 / 40uV) << 3 = 1 / 5uV
475 */
476 if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM)
477 regval = DIV_ROUND_CLOSEST(voltage_uv, 20) & 0xfffe;
478 else
479 regval = DIV_ROUND_CLOSEST(voltage_uv, 5) & 0xfff8;
480
481 return regmap_write(map: ina->regmap, reg, val: regval);
482}
483
484static int ina3221_write_enable(struct device *dev, int channel, bool enable)
485{
486 struct ina3221_data *ina = dev_get_drvdata(dev);
487 u16 config, mask = INA3221_CONFIG_CHx_EN(channel);
488 u16 config_old = ina->reg_config & mask;
489 u32 tmp;
490 int ret;
491
492 config = enable ? mask : 0;
493
494 /* Bypass if enable status is not being changed */
495 if (config_old == config)
496 return 0;
497
498 /* For enabling routine, increase refcount and resume() at first */
499 if (enable) {
500 ret = pm_runtime_resume_and_get(dev: ina->pm_dev);
501 if (ret < 0) {
502 dev_err(dev, "Failed to get PM runtime\n");
503 return ret;
504 }
505 }
506
507 /* Enable or disable the channel */
508 tmp = (ina->reg_config & ~mask) | (config & mask);
509 ret = regmap_write(map: ina->regmap, INA3221_CONFIG, val: tmp);
510 if (ret)
511 goto fail;
512
513 /* Cache the latest config register value */
514 ina->reg_config = tmp;
515
516 /* For disabling routine, decrease refcount or suspend() at last */
517 if (!enable)
518 pm_runtime_put_sync(dev: ina->pm_dev);
519
520 return 0;
521
522fail:
523 if (enable) {
524 dev_err(dev, "Failed to enable channel %d: error %d\n",
525 channel, ret);
526 pm_runtime_put_sync(dev: ina->pm_dev);
527 }
528
529 return ret;
530}
531
532static int ina3221_read(struct device *dev, enum hwmon_sensor_types type,
533 u32 attr, int channel, long *val)
534{
535 struct ina3221_data *ina = dev_get_drvdata(dev);
536 int ret;
537
538 mutex_lock(&ina->lock);
539
540 switch (type) {
541 case hwmon_chip:
542 ret = ina3221_read_chip(dev, attr, val);
543 break;
544 case hwmon_in:
545 /* 0-align channel ID */
546 ret = ina3221_read_in(dev, attr, channel: channel - 1, val);
547 break;
548 case hwmon_curr:
549 ret = ina3221_read_curr(dev, attr, channel, val);
550 break;
551 default:
552 ret = -EOPNOTSUPP;
553 break;
554 }
555
556 mutex_unlock(lock: &ina->lock);
557
558 return ret;
559}
560
561static int ina3221_write(struct device *dev, enum hwmon_sensor_types type,
562 u32 attr, int channel, long val)
563{
564 struct ina3221_data *ina = dev_get_drvdata(dev);
565 int ret;
566
567 mutex_lock(&ina->lock);
568
569 switch (type) {
570 case hwmon_chip:
571 ret = ina3221_write_chip(dev, attr, val);
572 break;
573 case hwmon_in:
574 /* 0-align channel ID */
575 ret = ina3221_write_enable(dev, channel: channel - 1, enable: val);
576 break;
577 case hwmon_curr:
578 ret = ina3221_write_curr(dev, attr, channel, val);
579 break;
580 default:
581 ret = -EOPNOTSUPP;
582 break;
583 }
584
585 mutex_unlock(lock: &ina->lock);
586
587 return ret;
588}
589
590static int ina3221_read_string(struct device *dev, enum hwmon_sensor_types type,
591 u32 attr, int channel, const char **str)
592{
593 struct ina3221_data *ina = dev_get_drvdata(dev);
594 int index = channel - 1;
595
596 if (channel == 7)
597 *str = "sum of shunt voltages";
598 else
599 *str = ina->inputs[index].label;
600
601 return 0;
602}
603
604static umode_t ina3221_is_visible(const void *drvdata,
605 enum hwmon_sensor_types type,
606 u32 attr, int channel)
607{
608 const struct ina3221_data *ina = drvdata;
609 const struct ina3221_input *input = NULL;
610
611 switch (type) {
612 case hwmon_chip:
613 switch (attr) {
614 case hwmon_chip_samples:
615 case hwmon_chip_update_interval:
616 return 0644;
617 default:
618 return 0;
619 }
620 case hwmon_in:
621 /* Ignore in0_ */
622 if (channel == 0)
623 return 0;
624
625 switch (attr) {
626 case hwmon_in_label:
627 if (channel - 1 <= INA3221_CHANNEL3)
628 input = &ina->inputs[channel - 1];
629 else if (channel == 7)
630 return 0444;
631 /* Hide label node if label is not provided */
632 return (input && input->label) ? 0444 : 0;
633 case hwmon_in_input:
634 return 0444;
635 case hwmon_in_enable:
636 return 0644;
637 default:
638 return 0;
639 }
640 case hwmon_curr:
641 switch (attr) {
642 case hwmon_curr_input:
643 case hwmon_curr_crit_alarm:
644 case hwmon_curr_max_alarm:
645 return 0444;
646 case hwmon_curr_crit:
647 case hwmon_curr_max:
648 return 0644;
649 default:
650 return 0;
651 }
652 default:
653 return 0;
654 }
655}
656
657#define INA3221_HWMON_CURR_CONFIG (HWMON_C_INPUT | \
658 HWMON_C_CRIT | HWMON_C_CRIT_ALARM | \
659 HWMON_C_MAX | HWMON_C_MAX_ALARM)
660
661static const struct hwmon_channel_info * const ina3221_info[] = {
662 HWMON_CHANNEL_INFO(chip,
663 HWMON_C_SAMPLES,
664 HWMON_C_UPDATE_INTERVAL),
665 HWMON_CHANNEL_INFO(in,
666 /* 0: dummy, skipped in is_visible */
667 HWMON_I_INPUT,
668 /* 1-3: input voltage Channels */
669 HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
670 HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
671 HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
672 /* 4-6: shunt voltage Channels */
673 HWMON_I_INPUT,
674 HWMON_I_INPUT,
675 HWMON_I_INPUT,
676 /* 7: summation of shunt voltage channels */
677 HWMON_I_INPUT | HWMON_I_LABEL),
678 HWMON_CHANNEL_INFO(curr,
679 /* 1-3: current channels*/
680 INA3221_HWMON_CURR_CONFIG,
681 INA3221_HWMON_CURR_CONFIG,
682 INA3221_HWMON_CURR_CONFIG,
683 /* 4: summation of current channels */
684 HWMON_C_INPUT | HWMON_C_CRIT | HWMON_C_CRIT_ALARM),
685 NULL
686};
687
688static const struct hwmon_ops ina3221_hwmon_ops = {
689 .is_visible = ina3221_is_visible,
690 .read_string = ina3221_read_string,
691 .read = ina3221_read,
692 .write = ina3221_write,
693};
694
695static const struct hwmon_chip_info ina3221_chip_info = {
696 .ops = &ina3221_hwmon_ops,
697 .info = ina3221_info,
698};
699
700/* Extra attribute groups */
701static ssize_t ina3221_shunt_show(struct device *dev,
702 struct device_attribute *attr, char *buf)
703{
704 struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
705 struct ina3221_data *ina = dev_get_drvdata(dev);
706 unsigned int channel = sd_attr->index;
707 struct ina3221_input *input = &ina->inputs[channel];
708
709 return sysfs_emit(buf, fmt: "%d\n", input->shunt_resistor);
710}
711
712static ssize_t ina3221_shunt_store(struct device *dev,
713 struct device_attribute *attr,
714 const char *buf, size_t count)
715{
716 struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
717 struct ina3221_data *ina = dev_get_drvdata(dev);
718 unsigned int channel = sd_attr->index;
719 struct ina3221_input *input = &ina->inputs[channel];
720 int val;
721 int ret;
722
723 ret = kstrtoint(s: buf, base: 0, res: &val);
724 if (ret)
725 return ret;
726
727 val = clamp_val(val, 1, INT_MAX);
728
729 input->shunt_resistor = val;
730
731 /* Update summation_shunt_resistor for summation channel */
732 ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina);
733
734 return count;
735}
736
737/* shunt resistance */
738static SENSOR_DEVICE_ATTR_RW(shunt1_resistor, ina3221_shunt, INA3221_CHANNEL1);
739static SENSOR_DEVICE_ATTR_RW(shunt2_resistor, ina3221_shunt, INA3221_CHANNEL2);
740static SENSOR_DEVICE_ATTR_RW(shunt3_resistor, ina3221_shunt, INA3221_CHANNEL3);
741
742static struct attribute *ina3221_attrs[] = {
743 &sensor_dev_attr_shunt1_resistor.dev_attr.attr,
744 &sensor_dev_attr_shunt2_resistor.dev_attr.attr,
745 &sensor_dev_attr_shunt3_resistor.dev_attr.attr,
746 NULL,
747};
748ATTRIBUTE_GROUPS(ina3221);
749
750static const struct regmap_range ina3221_yes_ranges[] = {
751 regmap_reg_range(INA3221_CONFIG, INA3221_BUS3),
752 regmap_reg_range(INA3221_SHUNT_SUM, INA3221_SHUNT_SUM),
753 regmap_reg_range(INA3221_MASK_ENABLE, INA3221_MASK_ENABLE),
754};
755
756static const struct regmap_access_table ina3221_volatile_table = {
757 .yes_ranges = ina3221_yes_ranges,
758 .n_yes_ranges = ARRAY_SIZE(ina3221_yes_ranges),
759};
760
761static const struct regmap_config ina3221_regmap_config = {
762 .reg_bits = 8,
763 .val_bits = 16,
764
765 .cache_type = REGCACHE_RBTREE,
766 .volatile_table = &ina3221_volatile_table,
767};
768
769static int ina3221_probe_child_from_dt(struct device *dev,
770 struct device_node *child,
771 struct ina3221_data *ina)
772{
773 struct ina3221_input *input;
774 u32 val;
775 int ret;
776
777 ret = of_property_read_u32(np: child, propname: "reg", out_value: &val);
778 if (ret) {
779 dev_err(dev, "missing reg property of %pOFn\n", child);
780 return ret;
781 } else if (val > INA3221_CHANNEL3) {
782 dev_err(dev, "invalid reg %d of %pOFn\n", val, child);
783 return -EINVAL;
784 }
785
786 input = &ina->inputs[val];
787
788 /* Log the disconnected channel input */
789 if (!of_device_is_available(device: child)) {
790 input->disconnected = true;
791 return 0;
792 }
793
794 /* Save the connected input label if available */
795 of_property_read_string(np: child, propname: "label", out_string: &input->label);
796
797 /* summation channel control */
798 input->summation_disable = of_property_read_bool(np: child, propname: "ti,summation-disable");
799
800 /* Overwrite default shunt resistor value optionally */
801 if (!of_property_read_u32(np: child, propname: "shunt-resistor-micro-ohms", out_value: &val)) {
802 if (val < 1 || val > INT_MAX) {
803 dev_err(dev, "invalid shunt resistor value %u of %pOFn\n",
804 val, child);
805 return -EINVAL;
806 }
807 input->shunt_resistor = val;
808 }
809
810 return 0;
811}
812
813static int ina3221_probe_from_dt(struct device *dev, struct ina3221_data *ina)
814{
815 const struct device_node *np = dev->of_node;
816 struct device_node *child;
817 int ret;
818
819 /* Compatible with non-DT platforms */
820 if (!np)
821 return 0;
822
823 ina->single_shot = of_property_read_bool(np, propname: "ti,single-shot");
824
825 for_each_child_of_node(np, child) {
826 ret = ina3221_probe_child_from_dt(dev, child, ina);
827 if (ret) {
828 of_node_put(node: child);
829 return ret;
830 }
831 }
832
833 return 0;
834}
835
836static int ina3221_probe(struct i2c_client *client)
837{
838 struct device *dev = &client->dev;
839 struct ina3221_data *ina;
840 struct device *hwmon_dev;
841 char name[32];
842 int i, ret;
843
844 ina = devm_kzalloc(dev, size: sizeof(*ina), GFP_KERNEL);
845 if (!ina)
846 return -ENOMEM;
847
848 ina->regmap = devm_regmap_init_i2c(client, &ina3221_regmap_config);
849 if (IS_ERR(ptr: ina->regmap)) {
850 dev_err(dev, "Unable to allocate register map\n");
851 return PTR_ERR(ptr: ina->regmap);
852 }
853
854 for (i = 0; i < F_MAX_FIELDS; i++) {
855 ina->fields[i] = devm_regmap_field_alloc(dev,
856 regmap: ina->regmap,
857 reg_field: ina3221_reg_fields[i]);
858 if (IS_ERR(ptr: ina->fields[i])) {
859 dev_err(dev, "Unable to allocate regmap fields\n");
860 return PTR_ERR(ptr: ina->fields[i]);
861 }
862 }
863
864 for (i = 0; i < INA3221_NUM_CHANNELS; i++)
865 ina->inputs[i].shunt_resistor = INA3221_RSHUNT_DEFAULT;
866
867 ret = ina3221_probe_from_dt(dev, ina);
868 if (ret) {
869 dev_err(dev, "Unable to probe from device tree\n");
870 return ret;
871 }
872
873 /* The driver will be reset, so use reset value */
874 ina->reg_config = INA3221_CONFIG_DEFAULT;
875
876 /* Clear continuous bit to use single-shot mode */
877 if (ina->single_shot)
878 ina->reg_config &= ~INA3221_CONFIG_MODE_CONTINUOUS;
879
880 /* Disable channels if their inputs are disconnected */
881 for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
882 if (ina->inputs[i].disconnected)
883 ina->reg_config &= ~INA3221_CONFIG_CHx_EN(i);
884 }
885
886 /* Initialize summation_shunt_resistor for summation channel control */
887 ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina);
888 for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
889 if (!ina->inputs[i].summation_disable)
890 ina->summation_channel_control |= BIT(14 - i);
891 }
892
893 ina->pm_dev = dev;
894 mutex_init(&ina->lock);
895 dev_set_drvdata(dev, data: ina);
896
897 /* Enable PM runtime -- status is suspended by default */
898 pm_runtime_enable(dev: ina->pm_dev);
899
900 /* Initialize (resume) the device */
901 for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
902 if (ina->inputs[i].disconnected)
903 continue;
904 /* Match the refcount with number of enabled channels */
905 ret = pm_runtime_get_sync(dev: ina->pm_dev);
906 if (ret < 0)
907 goto fail;
908 }
909
910 hwmon_dev = devm_hwmon_device_register_with_info(dev, name: client->name, drvdata: ina,
911 info: &ina3221_chip_info,
912 extra_groups: ina3221_groups);
913 if (IS_ERR(ptr: hwmon_dev)) {
914 dev_err(dev, "Unable to register hwmon device\n");
915 ret = PTR_ERR(ptr: hwmon_dev);
916 goto fail;
917 }
918
919 scnprintf(buf: name, size: sizeof(name), fmt: "%s-%s", INA3221_DRIVER_NAME, dev_name(dev));
920 ina->debugfs = debugfs_create_dir(name, NULL);
921
922 for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
923 scnprintf(buf: name, size: sizeof(name), fmt: "in%d_summation_disable", i);
924 debugfs_create_bool(name, mode: 0400, parent: ina->debugfs,
925 value: &ina->inputs[i].summation_disable);
926 }
927
928 return 0;
929
930fail:
931 pm_runtime_disable(dev: ina->pm_dev);
932 pm_runtime_set_suspended(dev: ina->pm_dev);
933 /* pm_runtime_put_noidle() will decrease the PM refcount until 0 */
934 for (i = 0; i < INA3221_NUM_CHANNELS; i++)
935 pm_runtime_put_noidle(dev: ina->pm_dev);
936 mutex_destroy(lock: &ina->lock);
937
938 return ret;
939}
940
941static void ina3221_remove(struct i2c_client *client)
942{
943 struct ina3221_data *ina = dev_get_drvdata(dev: &client->dev);
944 int i;
945
946 debugfs_remove_recursive(dentry: ina->debugfs);
947
948 pm_runtime_disable(dev: ina->pm_dev);
949 pm_runtime_set_suspended(dev: ina->pm_dev);
950
951 /* pm_runtime_put_noidle() will decrease the PM refcount until 0 */
952 for (i = 0; i < INA3221_NUM_CHANNELS; i++)
953 pm_runtime_put_noidle(dev: ina->pm_dev);
954
955 mutex_destroy(lock: &ina->lock);
956}
957
958static int ina3221_suspend(struct device *dev)
959{
960 struct ina3221_data *ina = dev_get_drvdata(dev);
961 int ret;
962
963 /* Save config register value and enable cache-only */
964 ret = regmap_read(map: ina->regmap, INA3221_CONFIG, val: &ina->reg_config);
965 if (ret)
966 return ret;
967
968 /* Set to power-down mode for power saving */
969 ret = regmap_update_bits(map: ina->regmap, INA3221_CONFIG,
970 INA3221_CONFIG_MODE_MASK,
971 INA3221_CONFIG_MODE_POWERDOWN);
972 if (ret)
973 return ret;
974
975 regcache_cache_only(map: ina->regmap, enable: true);
976 regcache_mark_dirty(map: ina->regmap);
977
978 return 0;
979}
980
981static int ina3221_resume(struct device *dev)
982{
983 struct ina3221_data *ina = dev_get_drvdata(dev);
984 int ret;
985
986 regcache_cache_only(map: ina->regmap, enable: false);
987
988 /* Software reset the chip */
989 ret = regmap_field_write(field: ina->fields[F_RST], val: true);
990 if (ret) {
991 dev_err(dev, "Unable to reset device\n");
992 return ret;
993 }
994
995 /* Restore cached register values to hardware */
996 ret = regcache_sync(map: ina->regmap);
997 if (ret)
998 return ret;
999
1000 /* Restore config register value to hardware */
1001 ret = regmap_write(map: ina->regmap, INA3221_CONFIG, val: ina->reg_config);
1002 if (ret)
1003 return ret;
1004
1005 /* Initialize summation channel control */
1006 if (ina->summation_shunt_resistor) {
1007 /*
1008 * Sum only channels that are not disabled for summation.
1009 * Shunt measurements of disconnected channels should
1010 * be 0, so it does not matter for summation.
1011 */
1012 ret = regmap_update_bits(map: ina->regmap, INA3221_MASK_ENABLE,
1013 INA3221_MASK_ENABLE_SCC_MASK,
1014 val: ina->summation_channel_control);
1015 if (ret) {
1016 dev_err(dev, "Unable to control summation channel\n");
1017 return ret;
1018 }
1019 }
1020
1021 return 0;
1022}
1023
1024static DEFINE_RUNTIME_DEV_PM_OPS(ina3221_pm, ina3221_suspend, ina3221_resume,
1025 NULL);
1026
1027static const struct of_device_id ina3221_of_match_table[] = {
1028 { .compatible = "ti,ina3221", },
1029 { /* sentinel */ }
1030};
1031MODULE_DEVICE_TABLE(of, ina3221_of_match_table);
1032
1033static const struct i2c_device_id ina3221_ids[] = {
1034 { "ina3221", 0 },
1035 { /* sentinel */ }
1036};
1037MODULE_DEVICE_TABLE(i2c, ina3221_ids);
1038
1039static struct i2c_driver ina3221_i2c_driver = {
1040 .probe = ina3221_probe,
1041 .remove = ina3221_remove,
1042 .driver = {
1043 .name = INA3221_DRIVER_NAME,
1044 .of_match_table = ina3221_of_match_table,
1045 .pm = pm_ptr(&ina3221_pm),
1046 },
1047 .id_table = ina3221_ids,
1048};
1049module_i2c_driver(ina3221_i2c_driver);
1050
1051MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
1052MODULE_DESCRIPTION("Texas Instruments INA3221 HWMon Driver");
1053MODULE_LICENSE("GPL v2");
1054

source code of linux/drivers/hwmon/ina3221.c