Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
hwmon: (ina238) Add support for current limits
Since the shunt voltage register and the current register now report the
same values, use the shunt voltage limit registers to report and adjust
current limits, using the same LSB as the LSB used for the actual current
register.
Handle current register accuracy differences in separate function to
improve code readability.
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz> # INA780
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
+87
-22
+4
Documentation/hwmon/ina238.rst
+4
Documentation/hwmon/ina238.rst
···
82
82
(SQ52206 only)
83
83
84
84
curr1_input Current measurement (mA)
85
+
curr1_min Minimum current threshold (mA)
86
+
curr1_min_alarm Minimum current alarm
87
+
curr1_max Maximum current threshold (mA)
88
+
curr1_max_alarm Maximum current alarm
85
89
86
90
energy1_input Energy measurement (uJ)
87
91
(SQ52206 and INA237 only)
+83
-22
drivers/hwmon/ina238.c
+83
-22
drivers/hwmon/ina238.c
···
335
335
}
336
336
}
337
337
338
-
static int ina238_read_current(struct device *dev, u32 attr, long *val)
338
+
static int __ina238_read_curr(struct ina238_data *data, long *val)
339
+
{
340
+
u32 lsb = data->current_lsb;
341
+
int err, regval;
342
+
343
+
if (data->config->has_20bit_voltage_current) {
344
+
err = ina238_read_field_s20(data->client, INA238_CURRENT, ®val);
345
+
if (err)
346
+
return err;
347
+
lsb /= 16; /* Adjust accuracy */
348
+
} else {
349
+
err = regmap_read(data->regmap, INA238_CURRENT, ®val);
350
+
if (err)
351
+
return err;
352
+
regval = (s16)regval;
353
+
}
354
+
355
+
*val = DIV_S64_ROUND_CLOSEST((s64)regval * lsb, 1000);
356
+
return 0;
357
+
}
358
+
359
+
static int ina238_read_curr(struct device *dev, u32 attr, long *val)
339
360
{
340
361
struct ina238_data *data = dev_get_drvdata(dev);
362
+
int reg, mask = 0;
341
363
int regval;
342
364
int err;
343
365
366
+
if (attr == hwmon_curr_input)
367
+
return __ina238_read_curr(data, val);
368
+
344
369
switch (attr) {
345
-
case hwmon_curr_input:
346
-
if (data->config->has_20bit_voltage_current) {
347
-
err = ina238_read_field_s20(data->client, INA238_CURRENT, ®val);
348
-
if (err)
349
-
return err;
350
-
} else {
351
-
err = regmap_read(data->regmap, INA238_CURRENT, ®val);
352
-
if (err < 0)
353
-
return err;
354
-
/* sign-extend */
355
-
regval = (s16)regval;
356
-
}
357
-
358
-
/* Signed register. Result in mA */
359
-
*val = DIV_S64_ROUND_CLOSEST((s64)regval * data->current_lsb, 1000);
360
-
361
-
/* Account for 4 bit offset */
362
-
if (data->config->has_20bit_voltage_current)
363
-
*val /= 16;
370
+
case hwmon_curr_min:
371
+
reg = INA238_SHUNT_UNDER_VOLTAGE;
372
+
break;
373
+
case hwmon_curr_min_alarm:
374
+
reg = INA238_DIAG_ALERT;
375
+
mask = INA238_DIAG_ALERT_SHNTUL;
376
+
break;
377
+
case hwmon_curr_max:
378
+
reg = INA238_SHUNT_OVER_VOLTAGE;
379
+
break;
380
+
case hwmon_curr_max_alarm:
381
+
reg = INA238_DIAG_ALERT;
382
+
mask = INA238_DIAG_ALERT_SHNTOL;
364
383
break;
365
384
default:
366
385
return -EOPNOTSUPP;
367
386
}
368
387
388
+
err = regmap_read(data->regmap, reg, ®val);
389
+
if (err < 0)
390
+
return err;
391
+
392
+
if (mask)
393
+
*val = !!(regval & mask);
394
+
else
395
+
*val = DIV_S64_ROUND_CLOSEST((s64)(s16)regval * data->current_lsb, 1000);
396
+
369
397
return 0;
398
+
}
399
+
400
+
static int ina238_write_curr(struct device *dev, u32 attr, long val)
401
+
{
402
+
struct ina238_data *data = dev_get_drvdata(dev);
403
+
int regval;
404
+
405
+
/* Set baseline range to avoid over/underflows */
406
+
val = clamp_val(val, -1000000, 1000000);
407
+
/* Scale */
408
+
val = DIV_ROUND_CLOSEST(val * 1000, data->current_lsb);
409
+
/* Clamp to register size */
410
+
regval = clamp_val(val, S16_MIN, S16_MAX) & 0xffff;
411
+
412
+
switch (attr) {
413
+
case hwmon_curr_min:
414
+
return regmap_write(data->regmap, INA238_SHUNT_UNDER_VOLTAGE,
415
+
regval);
416
+
case hwmon_curr_max:
417
+
return regmap_write(data->regmap, INA238_SHUNT_OVER_VOLTAGE,
418
+
regval);
419
+
default:
420
+
return -EOPNOTSUPP;
421
+
}
370
422
}
371
423
372
424
static int ina238_read_power(struct device *dev, u32 attr, long *val)
···
573
521
case hwmon_in:
574
522
return ina238_read_in(dev, attr, channel, val);
575
523
case hwmon_curr:
576
-
return ina238_read_current(dev, attr, val);
524
+
return ina238_read_curr(dev, attr, val);
577
525
case hwmon_power:
578
526
return ina238_read_power(dev, attr, val);
579
527
case hwmon_temp:
···
595
543
switch (type) {
596
544
case hwmon_in:
597
545
err = ina238_write_in(dev, attr, channel, val);
546
+
break;
547
+
case hwmon_curr:
548
+
err = ina238_write_curr(dev, attr, val);
598
549
break;
599
550
case hwmon_power:
600
551
err = ina238_write_power_max(dev, val);
···
637
582
case hwmon_curr:
638
583
switch (attr) {
639
584
case hwmon_curr_input:
585
+
case hwmon_curr_max_alarm:
586
+
case hwmon_curr_min_alarm:
640
587
return 0444;
588
+
case hwmon_curr_max:
589
+
case hwmon_curr_min:
590
+
return 0644;
641
591
default:
642
592
return 0;
643
593
}
···
687
627
INA238_HWMON_IN_CONFIG),
688
628
HWMON_CHANNEL_INFO(curr,
689
629
/* 0: current through shunt */
690
-
HWMON_C_INPUT),
630
+
HWMON_C_INPUT | HWMON_C_MIN | HWMON_C_MIN_ALARM |
631
+
HWMON_C_MAX | HWMON_C_MAX_ALARM),
691
632
HWMON_CHANNEL_INFO(power,
692
633
/* 0: power */
693
634
HWMON_P_INPUT | HWMON_P_MAX |