1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * IIO driver for PAC1934 Multi-Channel DC Power/Energy Monitor
4 *
5 * Copyright (C) 2017-2024 Microchip Technology Inc. and its subsidiaries
6 *
7 * Author: Bogdan Bolocan <bogdan.bolocan@microchip.com>
8 * Author: Victor Tudose
9 * Author: Marius Cristea <marius.cristea@microchip.com>
10 *
11 * Datasheet for PAC1931, PAC1932, PAC1933 and PAC1934 can be found here:
12 * https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ProductDocuments/DataSheets/PAC1931-Family-Data-Sheet-DS20005850E.pdf
13 */
14
15 #include <linux/acpi.h>
16 #include <linux/bitfield.h>
17 #include <linux/delay.h>
18 #include <linux/device.h>
19 #include <linux/i2c.h>
20 #include <linux/iio/iio.h>
21 #include <linux/iio/sysfs.h>
22 #include <linux/unaligned.h>
23
24 /*
25 * maximum accumulation time should be (17 * 60 * 1000) around 17 minutes@1024 sps
26 * till PAC1934 accumulation registers starts to saturate
27 */
28 #define PAC1934_MAX_RFSH_LIMIT_MS 60000
29 /* 50msec is the timeout for validity of the cached registers */
30 #define PAC1934_MIN_POLLING_TIME_MS 50
31 /*
32 * 1000usec is the minimum wait time for normal conversions when sample
33 * rate doesn't change
34 */
35 #define PAC1934_MIN_UPDATE_WAIT_TIME_US 1000
36
37 /* 32000mV */
38 #define PAC1934_VOLTAGE_MILLIVOLTS_MAX 32000
39 /* voltage bits resolution when set for unsigned values */
40 #define PAC1934_VOLTAGE_U_RES 16
41 /* voltage bits resolution when set for signed values */
42 #define PAC1934_VOLTAGE_S_RES 15
43
44 /*
45 * max signed value that can be stored on 32 bits and 8 digits fractional value
46 * (2^31 - 1) * 10^8 + 99999999
47 */
48 #define PAC_193X_MAX_POWER_ACC 214748364799999999LL
49 /*
50 * min signed value that can be stored on 32 bits and 8 digits fractional value
51 * -(2^31) * 10^8 - 99999999
52 */
53 #define PAC_193X_MIN_POWER_ACC -214748364899999999LL
54
55 #define PAC1934_MAX_NUM_CHANNELS 4
56
57 #define PAC1934_MEAS_REG_LEN 76
58 #define PAC1934_CTRL_REG_LEN 12
59
60 #define PAC1934_DEFAULT_CHIP_SAMP_SPEED_HZ 1024
61
62 /* I2C address map */
63 #define PAC1934_REFRESH_REG_ADDR 0x00
64 #define PAC1934_CTRL_REG_ADDR 0x01
65 #define PAC1934_ACC_COUNT_REG_ADDR 0x02
66 #define PAC1934_VPOWER_ACC_1_ADDR 0x03
67 #define PAC1934_VPOWER_ACC_2_ADDR 0x04
68 #define PAC1934_VPOWER_ACC_3_ADDR 0x05
69 #define PAC1934_VPOWER_ACC_4_ADDR 0x06
70 #define PAC1934_VBUS_1_ADDR 0x07
71 #define PAC1934_VBUS_2_ADDR 0x08
72 #define PAC1934_VBUS_3_ADDR 0x09
73 #define PAC1934_VBUS_4_ADDR 0x0A
74 #define PAC1934_VSENSE_1_ADDR 0x0B
75 #define PAC1934_VSENSE_2_ADDR 0x0C
76 #define PAC1934_VSENSE_3_ADDR 0x0D
77 #define PAC1934_VSENSE_4_ADDR 0x0E
78 #define PAC1934_VBUS_AVG_1_ADDR 0x0F
79 #define PAC1934_VBUS_AVG_2_ADDR 0x10
80 #define PAC1934_VBUS_AVG_3_ADDR 0x11
81 #define PAC1934_VBUS_AVG_4_ADDR 0x12
82 #define PAC1934_VSENSE_AVG_1_ADDR 0x13
83 #define PAC1934_VSENSE_AVG_2_ADDR 0x14
84 #define PAC1934_VSENSE_AVG_3_ADDR 0x15
85 #define PAC1934_VSENSE_AVG_4_ADDR 0x16
86 #define PAC1934_VPOWER_1_ADDR 0x17
87 #define PAC1934_VPOWER_2_ADDR 0x18
88 #define PAC1934_VPOWER_3_ADDR 0x19
89 #define PAC1934_VPOWER_4_ADDR 0x1A
90 #define PAC1934_REFRESH_V_REG_ADDR 0x1F
91 #define PAC1934_CTRL_STAT_REGS_ADDR 0x1C
92 #define PAC1934_PID_REG_ADDR 0xFD
93 #define PAC1934_MID_REG_ADDR 0xFE
94 #define PAC1934_RID_REG_ADDR 0xFF
95
96 /* PRODUCT ID REGISTER + MANUFACTURER ID REGISTER + REVISION ID REGISTER */
97 #define PAC1934_ID_REG_LEN 3
98 #define PAC1934_PID_IDX 0
99 #define PAC1934_MID_IDX 1
100 #define PAC1934_RID_IDX 2
101
102 #define PAC1934_ACPI_GET_NAMES_AND_MOHMS_VALS 1
103 #define PAC1934_ACPI_GET_UOHMS_VALS 2
104 #define PAC1934_ACPI_GET_BIPOLAR_SETTINGS 4
105 #define PAC1934_ACPI_GET_SAMP 5
106
107 #define PAC1934_SAMPLE_RATE_SHIFT 6
108
109 #define PAC1934_VBUS_SENSE_REG_LEN 2
110 #define PAC1934_ACC_REG_LEN 3
111 #define PAC1934_VPOWER_REG_LEN 4
112 #define PAC1934_VPOWER_ACC_REG_LEN 6
113 #define PAC1934_MAX_REGISTER_LENGTH 6
114
115 #define PAC1934_CUSTOM_ATTR_FOR_CHANNEL 1
116
117 /*
118 * relative offsets when using multi-byte reads/writes even though these
119 * bytes are read one after the other, they are not at adjacent memory
120 * locations within the I2C memory map. The chip can skip some addresses
121 */
122 #define PAC1934_CHANNEL_DIS_REG_OFF 0
123 #define PAC1934_NEG_PWR_REG_OFF 1
124
125 /*
126 * when reading/writing multiple bytes from offset PAC1934_CHANNEL_DIS_REG_OFF,
127 * the chip jumps over the 0x1E (REFRESH_G) and 0x1F (REFRESH_V) offsets
128 */
129 #define PAC1934_SLOW_REG_OFF 2
130 #define PAC1934_CTRL_ACT_REG_OFF 3
131 #define PAC1934_CHANNEL_DIS_ACT_REG_OFF 4
132 #define PAC1934_NEG_PWR_ACT_REG_OFF 5
133 #define PAC1934_CTRL_LAT_REG_OFF 6
134 #define PAC1934_CHANNEL_DIS_LAT_REG_OFF 7
135 #define PAC1934_NEG_PWR_LAT_REG_OFF 8
136 #define PAC1934_PID_REG_OFF 9
137 #define PAC1934_MID_REG_OFF 10
138 #define PAC1934_REV_REG_OFF 11
139 #define PAC1934_CTRL_STATUS_INFO_LEN 12
140
141 #define PAC1934_MID 0x5D
142 #define PAC1931_PID 0x58
143 #define PAC1932_PID 0x59
144 #define PAC1933_PID 0x5A
145 #define PAC1934_PID 0x5B
146
147 /* Scale constant = (10^3 * 3.2 * 10^9 / 2^28) for mili Watt-second */
148 #define PAC1934_SCALE_CONSTANT 11921
149
150 #define PAC1934_MAX_VPOWER_RSHIFTED_BY_28B 11921
151 #define PAC1934_MAX_VSENSE_RSHIFTED_BY_16B 1525
152
153 #define PAC1934_DEV_ATTR(name) (&iio_dev_attr_##name.dev_attr.attr)
154
155 #define PAC1934_CRTL_SAMPLE_RATE_MASK GENMASK(7, 6)
156 #define PAC1934_CHAN_SLEEP_MASK BIT(5)
157 #define PAC1934_CHAN_SLEEP_SET BIT(5)
158 #define PAC1934_CHAN_SINGLE_MASK BIT(4)
159 #define PAC1934_CHAN_SINGLE_SHOT_SET BIT(4)
160 #define PAC1934_CHAN_ALERT_MASK BIT(3)
161 #define PAC1934_CHAN_ALERT_EN BIT(3)
162 #define PAC1934_CHAN_ALERT_CC_MASK BIT(2)
163 #define PAC1934_CHAN_ALERT_CC_EN BIT(2)
164 #define PAC1934_CHAN_OVF_ALERT_MASK BIT(1)
165 #define PAC1934_CHAN_OVF_ALERT_EN BIT(1)
166 #define PAC1934_CHAN_OVF_MASK BIT(0)
167
168 #define PAC1934_CHAN_DIS_CH1_OFF_MASK BIT(7)
169 #define PAC1934_CHAN_DIS_CH2_OFF_MASK BIT(6)
170 #define PAC1934_CHAN_DIS_CH3_OFF_MASK BIT(5)
171 #define PAC1934_CHAN_DIS_CH4_OFF_MASK BIT(4)
172 #define PAC1934_SMBUS_TIMEOUT_MASK BIT(3)
173 #define PAC1934_SMBUS_BYTECOUNT_MASK BIT(2)
174 #define PAC1934_SMBUS_NO_SKIP_MASK BIT(1)
175
176 #define PAC1934_NEG_PWR_CH1_BIDI_MASK BIT(7)
177 #define PAC1934_NEG_PWR_CH2_BIDI_MASK BIT(6)
178 #define PAC1934_NEG_PWR_CH3_BIDI_MASK BIT(5)
179 #define PAC1934_NEG_PWR_CH4_BIDI_MASK BIT(4)
180 #define PAC1934_NEG_PWR_CH1_BIDV_MASK BIT(3)
181 #define PAC1934_NEG_PWR_CH2_BIDV_MASK BIT(2)
182 #define PAC1934_NEG_PWR_CH3_BIDV_MASK BIT(1)
183 #define PAC1934_NEG_PWR_CH4_BIDV_MASK BIT(0)
184
185 /*
186 * Universal Unique Identifier (UUID),
187 * 033771E0-1705-47B4-9535-D1BBE14D9A09,
188 * is reserved to Microchip for the PAC1934.
189 */
190 #define PAC1934_DSM_UUID "033771E0-1705-47B4-9535-D1BBE14D9A09"
191
192 enum pac1934_ids {
193 PAC1931,
194 PAC1932,
195 PAC1933,
196 PAC1934
197 };
198
199 enum pac1934_samps {
200 PAC1934_SAMP_1024SPS,
201 PAC1934_SAMP_256SPS,
202 PAC1934_SAMP_64SPS,
203 PAC1934_SAMP_8SPS
204 };
205
206 /*
207 * these indexes are exactly describing the element order within a single
208 * PAC1934 phys channel IIO channel descriptor; see the static const struct
209 * iio_chan_spec pac1934_single_channel[] declaration
210 */
211 enum pac1934_ch_idx {
212 PAC1934_CH_ENERGY,
213 PAC1934_CH_POWER,
214 PAC1934_CH_VOLTAGE,
215 PAC1934_CH_CURRENT,
216 PAC1934_CH_VOLTAGE_AVERAGE,
217 PAC1934_CH_CURRENT_AVERAGE
218 };
219
220 /**
221 * struct pac1934_features - features of a pac1934 instance
222 * @phys_channels: number of physical channels supported by the chip
223 * @name: chip's name
224 */
225 struct pac1934_features {
226 u8 phys_channels;
227 const char *name;
228 };
229
230 static const unsigned int samp_rate_map_tbl[] = {
231 [PAC1934_SAMP_1024SPS] = 1024,
232 [PAC1934_SAMP_256SPS] = 256,
233 [PAC1934_SAMP_64SPS] = 64,
234 [PAC1934_SAMP_8SPS] = 8,
235 };
236
237 static const struct pac1934_features pac1934_chip_config[] = {
238 [PAC1931] = {
239 .phys_channels = 1,
240 .name = "pac1931",
241 },
242 [PAC1932] = {
243 .phys_channels = 2,
244 .name = "pac1932",
245 },
246 [PAC1933] = {
247 .phys_channels = 3,
248 .name = "pac1933",
249 },
250 [PAC1934] = {
251 .phys_channels = 4,
252 .name = "pac1934",
253 },
254 };
255
256 /**
257 * struct reg_data - data from the registers
258 * @meas_regs: snapshot of raw measurements registers
259 * @ctrl_regs: snapshot of control registers
260 * @energy_sec_acc: snapshot of energy values
261 * @vpower_acc: accumulated vpower values
262 * @vpower: snapshot of vpower registers
263 * @vbus: snapshot of vbus registers
264 * @vbus_avg: averages of vbus registers
265 * @vsense: snapshot of vsense registers
266 * @vsense_avg: averages of vsense registers
267 * @num_enabled_channels: count of how many chip channels are currently enabled
268 */
269 struct reg_data {
270 u8 meas_regs[PAC1934_MEAS_REG_LEN];
271 u8 ctrl_regs[PAC1934_CTRL_REG_LEN];
272 s64 energy_sec_acc[PAC1934_MAX_NUM_CHANNELS];
273 s64 vpower_acc[PAC1934_MAX_NUM_CHANNELS];
274 s32 vpower[PAC1934_MAX_NUM_CHANNELS];
275 s32 vbus[PAC1934_MAX_NUM_CHANNELS];
276 s32 vbus_avg[PAC1934_MAX_NUM_CHANNELS];
277 s32 vsense[PAC1934_MAX_NUM_CHANNELS];
278 s32 vsense_avg[PAC1934_MAX_NUM_CHANNELS];
279 u8 num_enabled_channels;
280 };
281
282 /**
283 * struct pac1934_chip_info - information about the chip
284 * @client: the i2c-client attached to the device
285 * @lock: synchronize access to driver's state members
286 * @work_chip_rfsh: work queue used for refresh commands
287 * @phys_channels: phys channels count
288 * @active_channels: array of values, true means that channel is active
289 * @enable_energy: array of values, true means that channel energy is measured
290 * @bi_dir: array of bools, true means that channel is bidirectional
291 * @chip_variant: chip variant
292 * @chip_revision: chip revision
293 * @shunts: shunts
294 * @chip_reg_data: chip reg data
295 * @sample_rate_value: sampling frequency
296 * @labels: table with channels labels
297 * @iio_info: iio_info
298 * @tstamp: chip's uptime
299 */
300 struct pac1934_chip_info {
301 struct i2c_client *client;
302 struct mutex lock; /* synchronize access to driver's state members */
303 struct delayed_work work_chip_rfsh;
304 u8 phys_channels;
305 bool active_channels[PAC1934_MAX_NUM_CHANNELS];
306 bool enable_energy[PAC1934_MAX_NUM_CHANNELS];
307 bool bi_dir[PAC1934_MAX_NUM_CHANNELS];
308 u8 chip_variant;
309 u8 chip_revision;
310 u32 shunts[PAC1934_MAX_NUM_CHANNELS];
311 struct reg_data chip_reg_data;
312 s32 sample_rate_value;
313 char *labels[PAC1934_MAX_NUM_CHANNELS];
314 struct iio_info iio_info;
315 unsigned long tstamp;
316 };
317
318 #define TO_PAC1934_CHIP_INFO(d) container_of(d, struct pac1934_chip_info, work_chip_rfsh)
319
320 #define PAC1934_VPOWER_ACC_CHANNEL(_index, _si, _address) { \
321 .type = IIO_ENERGY, \
322 .address = (_address), \
323 .indexed = 1, \
324 .channel = (_index), \
325 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
326 BIT(IIO_CHAN_INFO_SCALE) | \
327 BIT(IIO_CHAN_INFO_ENABLE), \
328 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
329 .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
330 .scan_index = (_si), \
331 .scan_type = { \
332 .sign = 'u', \
333 .realbits = 48, \
334 .storagebits = 64, \
335 .endianness = IIO_CPU, \
336 } \
337 }
338
339 #define PAC1934_VBUS_CHANNEL(_index, _si, _address) { \
340 .type = IIO_VOLTAGE, \
341 .address = (_address), \
342 .indexed = 1, \
343 .channel = (_index), \
344 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
345 BIT(IIO_CHAN_INFO_SCALE), \
346 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
347 .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
348 .scan_index = (_si), \
349 .scan_type = { \
350 .sign = 'u', \
351 .realbits = 16, \
352 .storagebits = 16, \
353 .endianness = IIO_CPU, \
354 } \
355 }
356
357 #define PAC1934_VBUS_AVG_CHANNEL(_index, _si, _address) { \
358 .type = IIO_VOLTAGE, \
359 .address = (_address), \
360 .indexed = 1, \
361 .channel = (_index), \
362 .info_mask_separate = BIT(IIO_CHAN_INFO_AVERAGE_RAW) | \
363 BIT(IIO_CHAN_INFO_SCALE), \
364 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
365 .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
366 .scan_index = (_si), \
367 .scan_type = { \
368 .sign = 'u', \
369 .realbits = 16, \
370 .storagebits = 16, \
371 .endianness = IIO_CPU, \
372 } \
373 }
374
375 #define PAC1934_VSENSE_CHANNEL(_index, _si, _address) { \
376 .type = IIO_CURRENT, \
377 .address = (_address), \
378 .indexed = 1, \
379 .channel = (_index), \
380 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
381 BIT(IIO_CHAN_INFO_SCALE), \
382 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
383 .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
384 .scan_index = (_si), \
385 .scan_type = { \
386 .sign = 'u', \
387 .realbits = 16, \
388 .storagebits = 16, \
389 .endianness = IIO_CPU, \
390 } \
391 }
392
393 #define PAC1934_VSENSE_AVG_CHANNEL(_index, _si, _address) { \
394 .type = IIO_CURRENT, \
395 .address = (_address), \
396 .indexed = 1, \
397 .channel = (_index), \
398 .info_mask_separate = BIT(IIO_CHAN_INFO_AVERAGE_RAW) | \
399 BIT(IIO_CHAN_INFO_SCALE), \
400 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
401 .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
402 .scan_index = (_si), \
403 .scan_type = { \
404 .sign = 'u', \
405 .realbits = 16, \
406 .storagebits = 16, \
407 .endianness = IIO_CPU, \
408 } \
409 }
410
411 #define PAC1934_VPOWER_CHANNEL(_index, _si, _address) { \
412 .type = IIO_POWER, \
413 .address = (_address), \
414 .indexed = 1, \
415 .channel = (_index), \
416 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
417 BIT(IIO_CHAN_INFO_SCALE), \
418 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
419 .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
420 .scan_index = (_si), \
421 .scan_type = { \
422 .sign = 'u', \
423 .realbits = 28, \
424 .storagebits = 32, \
425 .shift = 4, \
426 .endianness = IIO_CPU, \
427 } \
428 }
429
430 static const struct iio_chan_spec pac1934_single_channel[] = {
431 PAC1934_VPOWER_ACC_CHANNEL(0, 0, PAC1934_VPOWER_ACC_1_ADDR),
432 PAC1934_VPOWER_CHANNEL(0, 0, PAC1934_VPOWER_1_ADDR),
433 PAC1934_VBUS_CHANNEL(0, 0, PAC1934_VBUS_1_ADDR),
434 PAC1934_VSENSE_CHANNEL(0, 0, PAC1934_VSENSE_1_ADDR),
435 PAC1934_VBUS_AVG_CHANNEL(0, 0, PAC1934_VBUS_AVG_1_ADDR),
436 PAC1934_VSENSE_AVG_CHANNEL(0, 0, PAC1934_VSENSE_AVG_1_ADDR),
437 };
438
439 /* Low-level I2c functions used to transfer up to 76 bytes at once */
pac1934_i2c_read(struct i2c_client * client,u8 reg_addr,void * databuf,u8 len)440 static int pac1934_i2c_read(struct i2c_client *client, u8 reg_addr,
441 void *databuf, u8 len)
442 {
443 int ret;
444 struct i2c_msg msgs[2] = {
445 {
446 .addr = client->addr,
447 .len = 1,
448 .buf = (u8 *)®_addr,
449 },
450 {
451 .addr = client->addr,
452 .len = len,
453 .buf = databuf,
454 .flags = I2C_M_RD
455 }
456 };
457
458 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
459 if (ret < 0)
460 return ret;
461
462 return 0;
463 }
464
pac1934_get_samp_rate_idx(struct pac1934_chip_info * info,u32 new_samp_rate)465 static int pac1934_get_samp_rate_idx(struct pac1934_chip_info *info,
466 u32 new_samp_rate)
467 {
468 int cnt;
469
470 for (cnt = 0; cnt < ARRAY_SIZE(samp_rate_map_tbl); cnt++)
471 if (new_samp_rate == samp_rate_map_tbl[cnt])
472 return cnt;
473
474 /* not a valid sample rate value */
475 return -EINVAL;
476 }
477
pac1934_shunt_value_show(struct device * dev,struct device_attribute * attr,char * buf)478 static ssize_t pac1934_shunt_value_show(struct device *dev,
479 struct device_attribute *attr,
480 char *buf)
481 {
482 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
483 struct pac1934_chip_info *info = iio_priv(indio_dev);
484 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
485
486 return sysfs_emit(buf, "%u\n", info->shunts[this_attr->address]);
487 }
488
pac1934_shunt_value_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)489 static ssize_t pac1934_shunt_value_store(struct device *dev,
490 struct device_attribute *attr,
491 const char *buf, size_t count)
492 {
493 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
494 struct pac1934_chip_info *info = iio_priv(indio_dev);
495 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
496 int sh_val;
497
498 if (kstrtouint(buf, 10, &sh_val)) {
499 dev_err(dev, "Shunt value is not valid\n");
500 return -EINVAL;
501 }
502
503 scoped_guard(mutex, &info->lock)
504 info->shunts[this_attr->address] = sh_val;
505
506 return count;
507 }
508
pac1934_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * channel,const int ** vals,int * type,int * length,long mask)509 static int pac1934_read_avail(struct iio_dev *indio_dev,
510 struct iio_chan_spec const *channel,
511 const int **vals, int *type, int *length, long mask)
512 {
513 switch (mask) {
514 case IIO_CHAN_INFO_SAMP_FREQ:
515 *type = IIO_VAL_INT;
516 *vals = samp_rate_map_tbl;
517 *length = ARRAY_SIZE(samp_rate_map_tbl);
518 return IIO_AVAIL_LIST;
519 }
520
521 return -EINVAL;
522 }
523
pac1934_send_refresh(struct pac1934_chip_info * info,u8 refresh_cmd,u32 wait_time)524 static int pac1934_send_refresh(struct pac1934_chip_info *info,
525 u8 refresh_cmd, u32 wait_time)
526 {
527 /* this function only sends REFRESH or REFRESH_V */
528 struct i2c_client *client = info->client;
529 int ret;
530 u8 bidir_reg;
531 bool revision_bug = false;
532
533 if (info->chip_revision == 2 || info->chip_revision == 3) {
534 /*
535 * chip rev 2 and 3 bug workaround
536 * see: PAC1934 Family Data Sheet Errata DS80000836A.pdf
537 */
538 revision_bug = true;
539
540 bidir_reg =
541 FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDI_MASK, info->bi_dir[0]) |
542 FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDI_MASK, info->bi_dir[1]) |
543 FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDI_MASK, info->bi_dir[2]) |
544 FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDI_MASK, info->bi_dir[3]) |
545 FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDV_MASK, info->bi_dir[0]) |
546 FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDV_MASK, info->bi_dir[1]) |
547 FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDV_MASK, info->bi_dir[2]) |
548 FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDV_MASK, info->bi_dir[3]);
549
550 ret = i2c_smbus_write_byte_data(client,
551 PAC1934_CTRL_STAT_REGS_ADDR +
552 PAC1934_NEG_PWR_REG_OFF,
553 bidir_reg);
554 if (ret)
555 return ret;
556 }
557
558 ret = i2c_smbus_write_byte(client, refresh_cmd);
559 if (ret) {
560 dev_err(&client->dev, "%s - cannot send 0x%02X\n",
561 __func__, refresh_cmd);
562 return ret;
563 }
564
565 if (revision_bug) {
566 /*
567 * chip rev 2 and 3 bug workaround - write again the same
568 * register write the updated registers back
569 */
570 ret = i2c_smbus_write_byte_data(client,
571 PAC1934_CTRL_STAT_REGS_ADDR +
572 PAC1934_NEG_PWR_REG_OFF, bidir_reg);
573 if (ret)
574 return ret;
575 }
576
577 /* register data retrieval timestamp */
578 info->tstamp = jiffies;
579
580 /* wait till the data is available */
581 usleep_range(wait_time, wait_time + 100);
582
583 return ret;
584 }
585
pac1934_reg_snapshot(struct pac1934_chip_info * info,bool do_refresh,u8 refresh_cmd,u32 wait_time)586 static int pac1934_reg_snapshot(struct pac1934_chip_info *info,
587 bool do_refresh, u8 refresh_cmd, u32 wait_time)
588 {
589 int ret;
590 struct i2c_client *client = info->client;
591 u8 samp_shift, ctrl_regs_tmp;
592 u8 *offset_reg_data_p;
593 u16 tmp_value;
594 u32 samp_rate, cnt, tmp;
595 s64 curr_energy, inc;
596 u64 tmp_energy;
597 struct reg_data *reg_data;
598
599 guard(mutex)(&info->lock);
600
601 if (do_refresh) {
602 ret = pac1934_send_refresh(info, refresh_cmd, wait_time);
603 if (ret < 0) {
604 dev_err(&client->dev,
605 "%s - cannot send refresh\n",
606 __func__);
607 return ret;
608 }
609 }
610
611 ret = i2c_smbus_read_i2c_block_data(client, PAC1934_CTRL_STAT_REGS_ADDR,
612 PAC1934_CTRL_REG_LEN,
613 (u8 *)info->chip_reg_data.ctrl_regs);
614 if (ret < 0) {
615 dev_err(&client->dev,
616 "%s - cannot read ctrl/status registers\n",
617 __func__);
618 return ret;
619 }
620
621 reg_data = &info->chip_reg_data;
622
623 /* read the data registers */
624 ret = pac1934_i2c_read(client, PAC1934_ACC_COUNT_REG_ADDR,
625 (u8 *)reg_data->meas_regs, PAC1934_MEAS_REG_LEN);
626 if (ret) {
627 dev_err(&client->dev,
628 "%s - cannot read ACC_COUNT register: %d:%d\n",
629 __func__, ret, PAC1934_MEAS_REG_LEN);
630 return ret;
631 }
632
633 /* see how much shift is required by the sample rate */
634 samp_rate = samp_rate_map_tbl[((reg_data->ctrl_regs[PAC1934_CTRL_LAT_REG_OFF]) >> 6)];
635 samp_shift = get_count_order(samp_rate);
636
637 ctrl_regs_tmp = reg_data->ctrl_regs[PAC1934_CHANNEL_DIS_LAT_REG_OFF];
638 offset_reg_data_p = ®_data->meas_regs[PAC1934_ACC_REG_LEN];
639
640 /* start with VPOWER_ACC */
641 for (cnt = 0; cnt < info->phys_channels; cnt++) {
642 /* check if the channel is active, skip all fields if disabled */
643 if ((ctrl_regs_tmp << cnt) & 0x80)
644 continue;
645
646 /* skip if the energy accumulation is disabled */
647 if (info->enable_energy[cnt]) {
648 curr_energy = info->chip_reg_data.energy_sec_acc[cnt];
649
650 tmp_energy = get_unaligned_be48(offset_reg_data_p);
651
652 if (info->bi_dir[cnt])
653 reg_data->vpower_acc[cnt] = sign_extend64(tmp_energy, 47);
654 else
655 reg_data->vpower_acc[cnt] = tmp_energy;
656
657 /*
658 * compute the scaled to 1 second accumulated energy value;
659 * energy accumulator scaled to 1sec = VPOWER_ACC/2^samp_shift
660 * the chip's sampling rate is 2^samp_shift samples/sec
661 */
662 inc = (reg_data->vpower_acc[cnt] >> samp_shift);
663
664 /* add the power_acc field */
665 curr_energy += inc;
666
667 clamp(curr_energy, PAC_193X_MIN_POWER_ACC, PAC_193X_MAX_POWER_ACC);
668
669 reg_data->energy_sec_acc[cnt] = curr_energy;
670 }
671
672 offset_reg_data_p += PAC1934_VPOWER_ACC_REG_LEN;
673 }
674
675 /* continue with VBUS */
676 for (cnt = 0; cnt < info->phys_channels; cnt++) {
677 if ((ctrl_regs_tmp << cnt) & 0x80)
678 continue;
679
680 tmp_value = get_unaligned_be16(offset_reg_data_p);
681
682 if (info->bi_dir[cnt])
683 reg_data->vbus[cnt] = sign_extend32((u32)(tmp_value), 15);
684 else
685 reg_data->vbus[cnt] = tmp_value;
686
687 offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
688 }
689
690 /* VSENSE */
691 for (cnt = 0; cnt < info->phys_channels; cnt++) {
692 if ((ctrl_regs_tmp << cnt) & 0x80)
693 continue;
694
695 tmp_value = get_unaligned_be16(offset_reg_data_p);
696
697 if (info->bi_dir[cnt])
698 reg_data->vsense[cnt] = sign_extend32((u32)(tmp_value), 15);
699 else
700 reg_data->vsense[cnt] = tmp_value;
701
702 offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
703 }
704
705 /* VBUS_AVG */
706 for (cnt = 0; cnt < info->phys_channels; cnt++) {
707 if ((ctrl_regs_tmp << cnt) & 0x80)
708 continue;
709
710 tmp_value = get_unaligned_be16(offset_reg_data_p);
711
712 if (info->bi_dir[cnt])
713 reg_data->vbus_avg[cnt] = sign_extend32((u32)(tmp_value), 15);
714 else
715 reg_data->vbus_avg[cnt] = tmp_value;
716
717 offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
718 }
719
720 /* VSENSE_AVG */
721 for (cnt = 0; cnt < info->phys_channels; cnt++) {
722 if ((ctrl_regs_tmp << cnt) & 0x80)
723 continue;
724
725 tmp_value = get_unaligned_be16(offset_reg_data_p);
726
727 if (info->bi_dir[cnt])
728 reg_data->vsense_avg[cnt] = sign_extend32((u32)(tmp_value), 15);
729 else
730 reg_data->vsense_avg[cnt] = tmp_value;
731
732 offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
733 }
734
735 /* VPOWER */
736 for (cnt = 0; cnt < info->phys_channels; cnt++) {
737 if ((ctrl_regs_tmp << cnt) & 0x80)
738 continue;
739
740 tmp = get_unaligned_be32(offset_reg_data_p) >> 4;
741
742 if (info->bi_dir[cnt])
743 reg_data->vpower[cnt] = sign_extend32(tmp, 27);
744 else
745 reg_data->vpower[cnt] = tmp;
746
747 offset_reg_data_p += PAC1934_VPOWER_REG_LEN;
748 }
749
750 return 0;
751 }
752
pac1934_retrieve_data(struct pac1934_chip_info * info,u32 wait_time)753 static int pac1934_retrieve_data(struct pac1934_chip_info *info,
754 u32 wait_time)
755 {
756 int ret = 0;
757
758 /*
759 * check if the minimal elapsed time has passed and if so,
760 * re-read the chip, otherwise the cached info is just fine
761 */
762 if (time_after(jiffies, info->tstamp + msecs_to_jiffies(PAC1934_MIN_POLLING_TIME_MS))) {
763 ret = pac1934_reg_snapshot(info, true, PAC1934_REFRESH_REG_ADDR,
764 wait_time);
765
766 /*
767 * Re-schedule the work for the read registers on timeout
768 * (to prevent chip registers saturation)
769 */
770 mod_delayed_work(system_wq, &info->work_chip_rfsh,
771 msecs_to_jiffies(PAC1934_MAX_RFSH_LIMIT_MS));
772 }
773
774 return ret;
775 }
776
pac1934_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)777 static int pac1934_read_raw(struct iio_dev *indio_dev,
778 struct iio_chan_spec const *chan, int *val,
779 int *val2, long mask)
780 {
781 struct pac1934_chip_info *info = iio_priv(indio_dev);
782 s64 curr_energy;
783 int ret, channel = chan->channel - 1;
784
785 /*
786 * For AVG the index should be between 5 to 8.
787 * To calculate PAC1934_CH_VOLTAGE_AVERAGE,
788 * respectively PAC1934_CH_CURRENT real index, we need
789 * to remove the added offset (PAC1934_MAX_NUM_CHANNELS).
790 */
791 if (channel >= PAC1934_MAX_NUM_CHANNELS)
792 channel = channel - PAC1934_MAX_NUM_CHANNELS;
793
794 ret = pac1934_retrieve_data(info, PAC1934_MIN_UPDATE_WAIT_TIME_US);
795 if (ret < 0)
796 return ret;
797
798 switch (mask) {
799 case IIO_CHAN_INFO_RAW:
800 switch (chan->type) {
801 case IIO_VOLTAGE:
802 *val = info->chip_reg_data.vbus[channel];
803 return IIO_VAL_INT;
804 case IIO_CURRENT:
805 *val = info->chip_reg_data.vsense[channel];
806 return IIO_VAL_INT;
807 case IIO_POWER:
808 *val = info->chip_reg_data.vpower[channel];
809 return IIO_VAL_INT;
810 case IIO_ENERGY:
811 curr_energy = info->chip_reg_data.energy_sec_acc[channel];
812 *val = (u32)curr_energy;
813 *val2 = (u32)(curr_energy >> 32);
814 return IIO_VAL_INT_64;
815 default:
816 return -EINVAL;
817 }
818 case IIO_CHAN_INFO_AVERAGE_RAW:
819 switch (chan->type) {
820 case IIO_VOLTAGE:
821 *val = info->chip_reg_data.vbus_avg[channel];
822 return IIO_VAL_INT;
823 case IIO_CURRENT:
824 *val = info->chip_reg_data.vsense_avg[channel];
825 return IIO_VAL_INT;
826 default:
827 return -EINVAL;
828 }
829 case IIO_CHAN_INFO_SCALE:
830 switch (chan->address) {
831 /* Voltages - scale for millivolts */
832 case PAC1934_VBUS_1_ADDR:
833 case PAC1934_VBUS_2_ADDR:
834 case PAC1934_VBUS_3_ADDR:
835 case PAC1934_VBUS_4_ADDR:
836 case PAC1934_VBUS_AVG_1_ADDR:
837 case PAC1934_VBUS_AVG_2_ADDR:
838 case PAC1934_VBUS_AVG_3_ADDR:
839 case PAC1934_VBUS_AVG_4_ADDR:
840 *val = PAC1934_VOLTAGE_MILLIVOLTS_MAX;
841 if (chan->scan_type.sign == 'u')
842 *val2 = PAC1934_VOLTAGE_U_RES;
843 else
844 *val2 = PAC1934_VOLTAGE_S_RES;
845 return IIO_VAL_FRACTIONAL_LOG2;
846 /*
847 * Currents - scale for mA - depends on the
848 * channel's shunt value
849 * (100mV * 1000000) / (2^16 * shunt(uohm))
850 */
851 case PAC1934_VSENSE_1_ADDR:
852 case PAC1934_VSENSE_2_ADDR:
853 case PAC1934_VSENSE_3_ADDR:
854 case PAC1934_VSENSE_4_ADDR:
855 case PAC1934_VSENSE_AVG_1_ADDR:
856 case PAC1934_VSENSE_AVG_2_ADDR:
857 case PAC1934_VSENSE_AVG_3_ADDR:
858 case PAC1934_VSENSE_AVG_4_ADDR:
859 *val = PAC1934_MAX_VSENSE_RSHIFTED_BY_16B;
860 if (chan->scan_type.sign == 'u')
861 *val2 = info->shunts[channel];
862 else
863 *val2 = info->shunts[channel] >> 1;
864 return IIO_VAL_FRACTIONAL;
865 /*
866 * Power - uW - it will use the combined scale
867 * for current and voltage
868 * current(mA) * voltage(mV) = power (uW)
869 */
870 case PAC1934_VPOWER_1_ADDR:
871 case PAC1934_VPOWER_2_ADDR:
872 case PAC1934_VPOWER_3_ADDR:
873 case PAC1934_VPOWER_4_ADDR:
874 *val = PAC1934_MAX_VPOWER_RSHIFTED_BY_28B;
875 if (chan->scan_type.sign == 'u')
876 *val2 = info->shunts[channel];
877 else
878 *val2 = info->shunts[channel] >> 1;
879 return IIO_VAL_FRACTIONAL;
880 case PAC1934_VPOWER_ACC_1_ADDR:
881 case PAC1934_VPOWER_ACC_2_ADDR:
882 case PAC1934_VPOWER_ACC_3_ADDR:
883 case PAC1934_VPOWER_ACC_4_ADDR:
884 /*
885 * expresses the 32 bit scale value here compute
886 * the scale for energy (miliWatt-second or miliJoule)
887 */
888 *val = PAC1934_SCALE_CONSTANT;
889
890 if (chan->scan_type.sign == 'u')
891 *val2 = info->shunts[channel];
892 else
893 *val2 = info->shunts[channel] >> 1;
894 return IIO_VAL_FRACTIONAL;
895 default:
896 return -EINVAL;
897 }
898 case IIO_CHAN_INFO_SAMP_FREQ:
899 *val = info->sample_rate_value;
900 return IIO_VAL_INT;
901 case IIO_CHAN_INFO_ENABLE:
902 *val = info->enable_energy[channel];
903 return IIO_VAL_INT;
904 default:
905 return -EINVAL;
906 }
907 }
908
pac1934_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)909 static int pac1934_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
910 int val, int val2, long mask)
911 {
912 struct pac1934_chip_info *info = iio_priv(indio_dev);
913 struct i2c_client *client = info->client;
914 int ret = -EINVAL;
915 s32 old_samp_rate;
916 u8 ctrl_reg;
917
918 switch (mask) {
919 case IIO_CHAN_INFO_SAMP_FREQ:
920 ret = pac1934_get_samp_rate_idx(info, val);
921 if (ret < 0)
922 return ret;
923
924 /* write the new sampling value and trigger a snapshot(incl refresh) */
925 scoped_guard(mutex, &info->lock) {
926 ctrl_reg = FIELD_PREP(PAC1934_CRTL_SAMPLE_RATE_MASK, ret);
927 ret = i2c_smbus_write_byte_data(client, PAC1934_CTRL_REG_ADDR, ctrl_reg);
928 if (ret) {
929 dev_err(&client->dev,
930 "%s - can't update sample rate\n",
931 __func__);
932 return ret;
933 }
934 }
935
936 old_samp_rate = info->sample_rate_value;
937 info->sample_rate_value = val;
938
939 /*
940 * now, force a snapshot with refresh - call retrieve
941 * data in order to update the refresh timer
942 * alter the timestamp in order to force trigger a
943 * register snapshot and a timestamp update
944 */
945 info->tstamp -= msecs_to_jiffies(PAC1934_MIN_POLLING_TIME_MS);
946 ret = pac1934_retrieve_data(info, (1024 / old_samp_rate) * 1000);
947 if (ret < 0) {
948 dev_err(&client->dev,
949 "%s - cannot snapshot ctrl and measurement regs\n",
950 __func__);
951 return ret;
952 }
953
954 return 0;
955 case IIO_CHAN_INFO_ENABLE:
956 scoped_guard(mutex, &info->lock) {
957 info->enable_energy[chan->channel - 1] = val ? true : false;
958 if (!val)
959 info->chip_reg_data.energy_sec_acc[chan->channel - 1] = 0;
960 }
961
962 return 0;
963 default:
964 return -EINVAL;
965 }
966 }
967
pac1934_read_label(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,char * label)968 static int pac1934_read_label(struct iio_dev *indio_dev,
969 struct iio_chan_spec const *chan, char *label)
970 {
971 struct pac1934_chip_info *info = iio_priv(indio_dev);
972
973 switch (chan->address) {
974 case PAC1934_VBUS_1_ADDR:
975 case PAC1934_VBUS_2_ADDR:
976 case PAC1934_VBUS_3_ADDR:
977 case PAC1934_VBUS_4_ADDR:
978 return sysfs_emit(label, "%s_VBUS_%d\n",
979 info->labels[chan->scan_index],
980 chan->scan_index + 1);
981 case PAC1934_VBUS_AVG_1_ADDR:
982 case PAC1934_VBUS_AVG_2_ADDR:
983 case PAC1934_VBUS_AVG_3_ADDR:
984 case PAC1934_VBUS_AVG_4_ADDR:
985 return sysfs_emit(label, "%s_VBUS_AVG_%d\n",
986 info->labels[chan->scan_index],
987 chan->scan_index + 1);
988 case PAC1934_VSENSE_1_ADDR:
989 case PAC1934_VSENSE_2_ADDR:
990 case PAC1934_VSENSE_3_ADDR:
991 case PAC1934_VSENSE_4_ADDR:
992 return sysfs_emit(label, "%s_IBUS_%d\n",
993 info->labels[chan->scan_index],
994 chan->scan_index + 1);
995 case PAC1934_VSENSE_AVG_1_ADDR:
996 case PAC1934_VSENSE_AVG_2_ADDR:
997 case PAC1934_VSENSE_AVG_3_ADDR:
998 case PAC1934_VSENSE_AVG_4_ADDR:
999 return sysfs_emit(label, "%s_IBUS_AVG_%d\n",
1000 info->labels[chan->scan_index],
1001 chan->scan_index + 1);
1002 case PAC1934_VPOWER_1_ADDR:
1003 case PAC1934_VPOWER_2_ADDR:
1004 case PAC1934_VPOWER_3_ADDR:
1005 case PAC1934_VPOWER_4_ADDR:
1006 return sysfs_emit(label, "%s_POWER_%d\n",
1007 info->labels[chan->scan_index],
1008 chan->scan_index + 1);
1009 case PAC1934_VPOWER_ACC_1_ADDR:
1010 case PAC1934_VPOWER_ACC_2_ADDR:
1011 case PAC1934_VPOWER_ACC_3_ADDR:
1012 case PAC1934_VPOWER_ACC_4_ADDR:
1013 return sysfs_emit(label, "%s_ENERGY_%d\n",
1014 info->labels[chan->scan_index],
1015 chan->scan_index + 1);
1016 }
1017
1018 return 0;
1019 }
1020
pac1934_work_periodic_rfsh(struct work_struct * work)1021 static void pac1934_work_periodic_rfsh(struct work_struct *work)
1022 {
1023 struct pac1934_chip_info *info = TO_PAC1934_CHIP_INFO((struct delayed_work *)work);
1024 struct device *dev = &info->client->dev;
1025
1026 dev_dbg(dev, "%s - Periodic refresh\n", __func__);
1027
1028 /* do a REFRESH, then read */
1029 pac1934_reg_snapshot(info, true, PAC1934_REFRESH_REG_ADDR,
1030 PAC1934_MIN_UPDATE_WAIT_TIME_US);
1031
1032 schedule_delayed_work(&info->work_chip_rfsh,
1033 msecs_to_jiffies(PAC1934_MAX_RFSH_LIMIT_MS));
1034 }
1035
pac1934_read_revision(struct pac1934_chip_info * info,u8 * buf)1036 static int pac1934_read_revision(struct pac1934_chip_info *info, u8 *buf)
1037 {
1038 int ret;
1039 struct i2c_client *client = info->client;
1040
1041 ret = i2c_smbus_read_i2c_block_data(client, PAC1934_PID_REG_ADDR,
1042 PAC1934_ID_REG_LEN,
1043 buf);
1044 if (ret < 0) {
1045 dev_err(&client->dev, "cannot read revision\n");
1046 return ret;
1047 }
1048
1049 return 0;
1050 }
1051
pac1934_chip_identify(struct pac1934_chip_info * info)1052 static int pac1934_chip_identify(struct pac1934_chip_info *info)
1053 {
1054 u8 rev_info[PAC1934_ID_REG_LEN];
1055 struct device *dev = &info->client->dev;
1056 int ret = 0;
1057
1058 ret = pac1934_read_revision(info, (u8 *)rev_info);
1059 if (ret)
1060 return ret;
1061
1062 info->chip_variant = rev_info[PAC1934_PID_IDX];
1063 info->chip_revision = rev_info[PAC1934_RID_IDX];
1064
1065 dev_dbg(dev, "Chip variant: 0x%02X\n", info->chip_variant);
1066 dev_dbg(dev, "Chip revision: 0x%02X\n", info->chip_revision);
1067
1068 switch (info->chip_variant) {
1069 case PAC1934_PID:
1070 return PAC1934;
1071 case PAC1933_PID:
1072 return PAC1933;
1073 case PAC1932_PID:
1074 return PAC1932;
1075 case PAC1931_PID:
1076 return PAC1931;
1077 default:
1078 return -EINVAL;
1079 }
1080 }
1081
1082 /*
1083 * documentation related to the ACPI device definition
1084 * https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ApplicationNotes/ApplicationNotes/PAC1934-Integration-Notes-for-Microsoft-Windows-10-and-Windows-11-Driver-Support-DS00002534.pdf
1085 */
pac1934_acpi_parse_channel_config(struct i2c_client * client,struct pac1934_chip_info * info)1086 static int pac1934_acpi_parse_channel_config(struct i2c_client *client,
1087 struct pac1934_chip_info *info)
1088 {
1089 acpi_handle handle;
1090 union acpi_object *rez;
1091 struct device *dev = &client->dev;
1092 unsigned short bi_dir_mask;
1093 int idx, i;
1094 guid_t guid;
1095
1096 handle = ACPI_HANDLE(dev);
1097
1098 guid_parse(PAC1934_DSM_UUID, &guid);
1099
1100 rez = acpi_evaluate_dsm(handle, &guid, 0, PAC1934_ACPI_GET_NAMES_AND_MOHMS_VALS, NULL);
1101 if (!rez)
1102 return -EINVAL;
1103
1104 for (i = 0; i < rez->package.count; i += 2) {
1105 idx = i / 2;
1106 info->labels[idx] =
1107 devm_kmemdup(dev, rez->package.elements[i].string.pointer,
1108 (size_t)rez->package.elements[i].string.length + 1,
1109 GFP_KERNEL);
1110 info->labels[idx][rez->package.elements[i].string.length] = '\0';
1111 info->shunts[idx] = rez->package.elements[i + 1].integer.value * 1000;
1112 info->active_channels[idx] = (info->shunts[idx] != 0);
1113 }
1114
1115 ACPI_FREE(rez);
1116
1117 rez = acpi_evaluate_dsm(handle, &guid, 1, PAC1934_ACPI_GET_UOHMS_VALS, NULL);
1118 if (!rez) {
1119 /*
1120 * initializing with default values
1121 * we assume all channels are unidirectional(the mask is zero)
1122 * and assign the default sampling rate
1123 */
1124 info->sample_rate_value = PAC1934_DEFAULT_CHIP_SAMP_SPEED_HZ;
1125 return 0;
1126 }
1127
1128 for (i = 0; i < rez->package.count; i++) {
1129 idx = i;
1130 info->shunts[idx] = rez->package.elements[i].integer.value;
1131 info->active_channels[idx] = (info->shunts[idx] != 0);
1132 }
1133
1134 ACPI_FREE(rez);
1135
1136 rez = acpi_evaluate_dsm(handle, &guid, 1, PAC1934_ACPI_GET_BIPOLAR_SETTINGS, NULL);
1137 if (!rez)
1138 return -EINVAL;
1139
1140 bi_dir_mask = rez->package.elements[0].integer.value;
1141 info->bi_dir[0] = ((bi_dir_mask & (1 << 3)) | (bi_dir_mask & (1 << 7))) != 0;
1142 info->bi_dir[1] = ((bi_dir_mask & (1 << 2)) | (bi_dir_mask & (1 << 6))) != 0;
1143 info->bi_dir[2] = ((bi_dir_mask & (1 << 1)) | (bi_dir_mask & (1 << 5))) != 0;
1144 info->bi_dir[3] = ((bi_dir_mask & (1 << 0)) | (bi_dir_mask & (1 << 4))) != 0;
1145
1146 ACPI_FREE(rez);
1147
1148 rez = acpi_evaluate_dsm(handle, &guid, 1, PAC1934_ACPI_GET_SAMP, NULL);
1149 if (!rez)
1150 return -EINVAL;
1151
1152 info->sample_rate_value = rez->package.elements[0].integer.value;
1153
1154 ACPI_FREE(rez);
1155
1156 return 0;
1157 }
1158
pac1934_fw_parse_channel_config(struct i2c_client * client,struct pac1934_chip_info * info)1159 static int pac1934_fw_parse_channel_config(struct i2c_client *client,
1160 struct pac1934_chip_info *info)
1161 {
1162 struct device *dev = &client->dev;
1163 unsigned int current_channel;
1164 int idx, ret;
1165
1166 info->sample_rate_value = 1024;
1167 current_channel = 1;
1168
1169 device_for_each_child_node_scoped(dev, node) {
1170 ret = fwnode_property_read_u32(node, "reg", &idx);
1171 if (ret)
1172 return dev_err_probe(dev, ret,
1173 "reading invalid channel index\n");
1174
1175 /* adjust idx to match channel index (1 to 4) from the datasheet */
1176 idx--;
1177
1178 if (current_channel >= (info->phys_channels + 1) ||
1179 idx >= info->phys_channels || idx < 0)
1180 return dev_err_probe(dev, -EINVAL,
1181 "%s: invalid channel_index %d value\n",
1182 fwnode_get_name(node), idx);
1183
1184 /* enable channel */
1185 info->active_channels[idx] = true;
1186
1187 ret = fwnode_property_read_u32(node, "shunt-resistor-micro-ohms",
1188 &info->shunts[idx]);
1189 if (ret)
1190 return dev_err_probe(dev, ret,
1191 "%s: invalid shunt-resistor value: %d\n",
1192 fwnode_get_name(node), info->shunts[idx]);
1193
1194 if (fwnode_property_present(node, "label")) {
1195 ret = fwnode_property_read_string(node, "label",
1196 (const char **)&info->labels[idx]);
1197 if (ret)
1198 return dev_err_probe(dev, ret,
1199 "%s: invalid rail-name value\n",
1200 fwnode_get_name(node));
1201 }
1202
1203 info->bi_dir[idx] = fwnode_property_read_bool(node, "bipolar");
1204
1205 current_channel++;
1206 }
1207
1208 return 0;
1209 }
1210
pac1934_cancel_delayed_work(void * dwork)1211 static void pac1934_cancel_delayed_work(void *dwork)
1212 {
1213 cancel_delayed_work_sync(dwork);
1214 }
1215
pac1934_chip_configure(struct pac1934_chip_info * info)1216 static int pac1934_chip_configure(struct pac1934_chip_info *info)
1217 {
1218 int cnt, ret;
1219 struct i2c_client *client = info->client;
1220 u8 regs[PAC1934_CTRL_STATUS_INFO_LEN], idx, ctrl_reg;
1221 u32 wait_time;
1222
1223 info->chip_reg_data.num_enabled_channels = 0;
1224 for (cnt = 0; cnt < info->phys_channels; cnt++) {
1225 if (info->active_channels[cnt])
1226 info->chip_reg_data.num_enabled_channels++;
1227 }
1228
1229 /*
1230 * read whatever information was gathered before the driver was loaded
1231 * establish which channels are enabled/disabled and then establish the
1232 * information retrieval mode (using SKIP or no).
1233 * Read the chip ID values
1234 */
1235 ret = i2c_smbus_read_i2c_block_data(client, PAC1934_CTRL_STAT_REGS_ADDR,
1236 ARRAY_SIZE(regs),
1237 (u8 *)regs);
1238 if (ret < 0) {
1239 dev_err_probe(&client->dev, ret,
1240 "%s - cannot read regs from 0x%02X\n",
1241 __func__, PAC1934_CTRL_STAT_REGS_ADDR);
1242 return ret;
1243 }
1244
1245 /* write the CHANNEL_DIS and the NEG_PWR registers */
1246 regs[PAC1934_CHANNEL_DIS_REG_OFF] =
1247 FIELD_PREP(PAC1934_CHAN_DIS_CH1_OFF_MASK, info->active_channels[0] ? 0 : 1) |
1248 FIELD_PREP(PAC1934_CHAN_DIS_CH2_OFF_MASK, info->active_channels[1] ? 0 : 1) |
1249 FIELD_PREP(PAC1934_CHAN_DIS_CH3_OFF_MASK, info->active_channels[2] ? 0 : 1) |
1250 FIELD_PREP(PAC1934_CHAN_DIS_CH4_OFF_MASK, info->active_channels[3] ? 0 : 1) |
1251 FIELD_PREP(PAC1934_SMBUS_TIMEOUT_MASK, 0) |
1252 FIELD_PREP(PAC1934_SMBUS_BYTECOUNT_MASK, 0) |
1253 FIELD_PREP(PAC1934_SMBUS_NO_SKIP_MASK, 0);
1254
1255 regs[PAC1934_NEG_PWR_REG_OFF] =
1256 FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDI_MASK, info->bi_dir[0]) |
1257 FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDI_MASK, info->bi_dir[1]) |
1258 FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDI_MASK, info->bi_dir[2]) |
1259 FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDI_MASK, info->bi_dir[3]) |
1260 FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDV_MASK, info->bi_dir[0]) |
1261 FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDV_MASK, info->bi_dir[1]) |
1262 FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDV_MASK, info->bi_dir[2]) |
1263 FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDV_MASK, info->bi_dir[3]);
1264
1265 /* no SLOW triggered REFRESH, clear POR */
1266 regs[PAC1934_SLOW_REG_OFF] = 0;
1267
1268 ret = i2c_smbus_write_block_data(client, PAC1934_CTRL_STAT_REGS_ADDR,
1269 ARRAY_SIZE(regs), (u8 *)regs);
1270 if (ret)
1271 return ret;
1272
1273 /* Default sampling rate */
1274 ctrl_reg = FIELD_PREP(PAC1934_CRTL_SAMPLE_RATE_MASK, PAC1934_SAMP_1024SPS);
1275
1276 ret = i2c_smbus_write_byte_data(client, PAC1934_CTRL_REG_ADDR, ctrl_reg);
1277 if (ret)
1278 return ret;
1279
1280 /*
1281 * send a REFRESH to the chip, so the new settings take place
1282 * as well as resetting the accumulators
1283 */
1284 ret = i2c_smbus_write_byte(client, PAC1934_REFRESH_REG_ADDR);
1285 if (ret) {
1286 dev_err(&client->dev,
1287 "%s - cannot send 0x%02X\n",
1288 __func__, PAC1934_REFRESH_REG_ADDR);
1289 return ret;
1290 }
1291
1292 /*
1293 * get the current(in the chip) sampling speed and compute the
1294 * required timeout based on its value
1295 * the timeout is 1/sampling_speed
1296 */
1297 idx = regs[PAC1934_CTRL_ACT_REG_OFF] >> PAC1934_SAMPLE_RATE_SHIFT;
1298 wait_time = (1024 / samp_rate_map_tbl[idx]) * 1000;
1299
1300 /*
1301 * wait the maximum amount of time to be on the safe side
1302 * the maximum wait time is for 8sps
1303 */
1304 usleep_range(wait_time, wait_time + 100);
1305
1306 INIT_DELAYED_WORK(&info->work_chip_rfsh, pac1934_work_periodic_rfsh);
1307 /* Setup the latest moment for reading the regs before saturation */
1308 schedule_delayed_work(&info->work_chip_rfsh,
1309 msecs_to_jiffies(PAC1934_MAX_RFSH_LIMIT_MS));
1310
1311 return devm_add_action_or_reset(&client->dev, pac1934_cancel_delayed_work,
1312 &info->work_chip_rfsh);
1313 }
1314
pac1934_prep_iio_channels(struct pac1934_chip_info * info,struct iio_dev * indio_dev)1315 static int pac1934_prep_iio_channels(struct pac1934_chip_info *info, struct iio_dev *indio_dev)
1316 {
1317 struct iio_chan_spec *ch_sp;
1318 int channel_size, attribute_count, cnt;
1319 void *dyn_ch_struct, *tmp_data;
1320 struct device *dev = &info->client->dev;
1321
1322 /* find out dynamically how many IIO channels we need */
1323 attribute_count = 0;
1324 channel_size = 0;
1325 for (cnt = 0; cnt < info->phys_channels; cnt++) {
1326 if (!info->active_channels[cnt])
1327 continue;
1328
1329 /* add the size of the properties of one chip physical channel */
1330 channel_size += sizeof(pac1934_single_channel);
1331 /* count how many enabled channels we have */
1332 attribute_count += ARRAY_SIZE(pac1934_single_channel);
1333 dev_dbg(dev, ":%s: Channel %d active\n", __func__, cnt + 1);
1334 }
1335
1336 dyn_ch_struct = devm_kzalloc(dev, channel_size, GFP_KERNEL);
1337 if (!dyn_ch_struct)
1338 return -EINVAL;
1339
1340 tmp_data = dyn_ch_struct;
1341
1342 /* populate the dynamic channels and make all the adjustments */
1343 for (cnt = 0; cnt < info->phys_channels; cnt++) {
1344 if (!info->active_channels[cnt])
1345 continue;
1346
1347 memcpy(tmp_data, pac1934_single_channel, sizeof(pac1934_single_channel));
1348 ch_sp = (struct iio_chan_spec *)tmp_data;
1349 ch_sp[PAC1934_CH_ENERGY].channel = cnt + 1;
1350 ch_sp[PAC1934_CH_ENERGY].scan_index = cnt;
1351 ch_sp[PAC1934_CH_ENERGY].address = cnt + PAC1934_VPOWER_ACC_1_ADDR;
1352 ch_sp[PAC1934_CH_POWER].channel = cnt + 1;
1353 ch_sp[PAC1934_CH_POWER].scan_index = cnt;
1354 ch_sp[PAC1934_CH_POWER].address = cnt + PAC1934_VPOWER_1_ADDR;
1355 ch_sp[PAC1934_CH_VOLTAGE].channel = cnt + 1;
1356 ch_sp[PAC1934_CH_VOLTAGE].scan_index = cnt;
1357 ch_sp[PAC1934_CH_VOLTAGE].address = cnt + PAC1934_VBUS_1_ADDR;
1358 ch_sp[PAC1934_CH_CURRENT].channel = cnt + 1;
1359 ch_sp[PAC1934_CH_CURRENT].scan_index = cnt;
1360 ch_sp[PAC1934_CH_CURRENT].address = cnt + PAC1934_VSENSE_1_ADDR;
1361
1362 /*
1363 * In order to be able to use labels for PAC1934_CH_VOLTAGE, and
1364 * PAC1934_CH_VOLTAGE_AVERAGE,respectively PAC1934_CH_CURRENT
1365 * and PAC1934_CH_CURRENT_AVERAGE we need to use different
1366 * channel numbers. We will add +5 (+1 to maximum PAC channels).
1367 */
1368 ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].channel = cnt + 5;
1369 ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].scan_index = cnt;
1370 ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].address = cnt + PAC1934_VBUS_AVG_1_ADDR;
1371 ch_sp[PAC1934_CH_CURRENT_AVERAGE].channel = cnt + 5;
1372 ch_sp[PAC1934_CH_CURRENT_AVERAGE].scan_index = cnt;
1373 ch_sp[PAC1934_CH_CURRENT_AVERAGE].address = cnt + PAC1934_VSENSE_AVG_1_ADDR;
1374
1375 /*
1376 * now modify the parameters in all channels if the
1377 * whole chip rail(channel) is bi-directional
1378 */
1379 if (info->bi_dir[cnt]) {
1380 ch_sp[PAC1934_CH_ENERGY].scan_type.sign = 's';
1381 ch_sp[PAC1934_CH_ENERGY].scan_type.realbits = 47;
1382 ch_sp[PAC1934_CH_POWER].scan_type.sign = 's';
1383 ch_sp[PAC1934_CH_POWER].scan_type.realbits = 27;
1384 ch_sp[PAC1934_CH_VOLTAGE].scan_type.sign = 's';
1385 ch_sp[PAC1934_CH_VOLTAGE].scan_type.realbits = 15;
1386 ch_sp[PAC1934_CH_CURRENT].scan_type.sign = 's';
1387 ch_sp[PAC1934_CH_CURRENT].scan_type.realbits = 15;
1388 ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].scan_type.sign = 's';
1389 ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].scan_type.realbits = 15;
1390 ch_sp[PAC1934_CH_CURRENT_AVERAGE].scan_type.sign = 's';
1391 ch_sp[PAC1934_CH_CURRENT_AVERAGE].scan_type.realbits = 15;
1392 }
1393 tmp_data += sizeof(pac1934_single_channel);
1394 }
1395
1396 /*
1397 * send the updated dynamic channel structure information towards IIO
1398 * prepare the required field for IIO class registration
1399 */
1400 indio_dev->num_channels = attribute_count;
1401 indio_dev->channels = (const struct iio_chan_spec *)dyn_ch_struct;
1402
1403 return 0;
1404 }
1405
1406 static IIO_DEVICE_ATTR(in_shunt_resistor1, 0644,
1407 pac1934_shunt_value_show, pac1934_shunt_value_store, 0);
1408 static IIO_DEVICE_ATTR(in_shunt_resistor2, 0644,
1409 pac1934_shunt_value_show, pac1934_shunt_value_store, 1);
1410 static IIO_DEVICE_ATTR(in_shunt_resistor3, 0644,
1411 pac1934_shunt_value_show, pac1934_shunt_value_store, 2);
1412 static IIO_DEVICE_ATTR(in_shunt_resistor4, 0644,
1413 pac1934_shunt_value_show, pac1934_shunt_value_store, 3);
1414
pac1934_prep_custom_attributes(struct pac1934_chip_info * info,struct iio_dev * indio_dev)1415 static int pac1934_prep_custom_attributes(struct pac1934_chip_info *info,
1416 struct iio_dev *indio_dev)
1417 {
1418 int i, active_channels_count = 0;
1419 struct attribute **pac1934_custom_attr;
1420 struct attribute_group *pac1934_group;
1421 struct device *dev = &info->client->dev;
1422
1423 for (i = 0 ; i < info->phys_channels; i++)
1424 if (info->active_channels[i])
1425 active_channels_count++;
1426
1427 pac1934_group = devm_kzalloc(dev, sizeof(*pac1934_group), GFP_KERNEL);
1428 if (!pac1934_group)
1429 return -ENOMEM;
1430
1431 pac1934_custom_attr = devm_kzalloc(dev,
1432 (PAC1934_CUSTOM_ATTR_FOR_CHANNEL *
1433 active_channels_count)
1434 * sizeof(*pac1934_group) + 1,
1435 GFP_KERNEL);
1436 if (!pac1934_custom_attr)
1437 return -ENOMEM;
1438
1439 i = 0;
1440 if (info->active_channels[0])
1441 pac1934_custom_attr[i++] = PAC1934_DEV_ATTR(in_shunt_resistor1);
1442
1443 if (info->active_channels[1])
1444 pac1934_custom_attr[i++] = PAC1934_DEV_ATTR(in_shunt_resistor2);
1445
1446 if (info->active_channels[2])
1447 pac1934_custom_attr[i++] = PAC1934_DEV_ATTR(in_shunt_resistor3);
1448
1449 if (info->active_channels[3])
1450 pac1934_custom_attr[i] = PAC1934_DEV_ATTR(in_shunt_resistor4);
1451
1452 pac1934_group->attrs = pac1934_custom_attr;
1453 info->iio_info.attrs = pac1934_group;
1454
1455 return 0;
1456 }
1457
pac1934_mutex_destroy(void * data)1458 static void pac1934_mutex_destroy(void *data)
1459 {
1460 struct mutex *lock = data;
1461
1462 mutex_destroy(lock);
1463 }
1464
1465 static const struct iio_info pac1934_info = {
1466 .read_raw = pac1934_read_raw,
1467 .write_raw = pac1934_write_raw,
1468 .read_avail = pac1934_read_avail,
1469 .read_label = pac1934_read_label,
1470 };
1471
pac1934_probe(struct i2c_client * client)1472 static int pac1934_probe(struct i2c_client *client)
1473 {
1474 struct pac1934_chip_info *info;
1475 const struct pac1934_features *chip;
1476 struct iio_dev *indio_dev;
1477 int cnt, ret;
1478 struct device *dev = &client->dev;
1479
1480 indio_dev = devm_iio_device_alloc(dev, sizeof(*info));
1481 if (!indio_dev)
1482 return -ENOMEM;
1483
1484 info = iio_priv(indio_dev);
1485
1486 info->client = client;
1487
1488 /* always start with energy accumulation enabled */
1489 for (cnt = 0; cnt < PAC1934_MAX_NUM_CHANNELS; cnt++)
1490 info->enable_energy[cnt] = true;
1491
1492 ret = pac1934_chip_identify(info);
1493 if (ret < 0) {
1494 /*
1495 * If failed to identify the hardware based on internal
1496 * registers, try using fallback compatible in device tree
1497 * to deal with some newer part number.
1498 */
1499 chip = i2c_get_match_data(client);
1500 if (!chip)
1501 return -EINVAL;
1502
1503 info->phys_channels = chip->phys_channels;
1504 indio_dev->name = chip->name;
1505 } else {
1506 info->phys_channels = pac1934_chip_config[ret].phys_channels;
1507 indio_dev->name = pac1934_chip_config[ret].name;
1508 }
1509
1510 if (acpi_match_device(dev->driver->acpi_match_table, dev))
1511 ret = pac1934_acpi_parse_channel_config(client, info);
1512 else
1513 /*
1514 * This makes it possible to use also ACPI PRP0001 for
1515 * registering the device using device tree properties.
1516 */
1517 ret = pac1934_fw_parse_channel_config(client, info);
1518
1519 if (ret)
1520 return dev_err_probe(dev, ret,
1521 "parameter parsing returned an error\n");
1522
1523 mutex_init(&info->lock);
1524 ret = devm_add_action_or_reset(dev, pac1934_mutex_destroy,
1525 &info->lock);
1526 if (ret < 0)
1527 return ret;
1528
1529 /*
1530 * do now any chip specific initialization (e.g. read/write
1531 * some registers), enable/disable certain channels, change the sampling
1532 * rate to the requested value
1533 */
1534 ret = pac1934_chip_configure(info);
1535 if (ret < 0)
1536 return ret;
1537
1538 /* prepare the channel information */
1539 ret = pac1934_prep_iio_channels(info, indio_dev);
1540 if (ret < 0)
1541 return ret;
1542
1543 info->iio_info = pac1934_info;
1544 indio_dev->info = &info->iio_info;
1545 indio_dev->modes = INDIO_DIRECT_MODE;
1546
1547 ret = pac1934_prep_custom_attributes(info, indio_dev);
1548 if (ret < 0)
1549 return dev_err_probe(dev, ret,
1550 "Can't configure custom attributes for PAC1934 device\n");
1551
1552 /*
1553 * read whatever has been accumulated in the chip so far
1554 * and reset the accumulators
1555 */
1556 ret = pac1934_reg_snapshot(info, true, PAC1934_REFRESH_REG_ADDR,
1557 PAC1934_MIN_UPDATE_WAIT_TIME_US);
1558 if (ret < 0)
1559 return ret;
1560
1561 ret = devm_iio_device_register(dev, indio_dev);
1562 if (ret < 0)
1563 return dev_err_probe(dev, ret,
1564 "Can't register IIO device\n");
1565
1566 return 0;
1567 }
1568
1569 static const struct i2c_device_id pac1934_id[] = {
1570 { .name = "pac1931", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1931] },
1571 { .name = "pac1932", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1932] },
1572 { .name = "pac1933", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1933] },
1573 { .name = "pac1934", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1934] },
1574 { }
1575 };
1576 MODULE_DEVICE_TABLE(i2c, pac1934_id);
1577
1578 static const struct of_device_id pac1934_of_match[] = {
1579 {
1580 .compatible = "microchip,pac1931",
1581 .data = &pac1934_chip_config[PAC1931]
1582 },
1583 {
1584 .compatible = "microchip,pac1932",
1585 .data = &pac1934_chip_config[PAC1932]
1586 },
1587 {
1588 .compatible = "microchip,pac1933",
1589 .data = &pac1934_chip_config[PAC1933]
1590 },
1591 {
1592 .compatible = "microchip,pac1934",
1593 .data = &pac1934_chip_config[PAC1934]
1594 },
1595 { }
1596 };
1597 MODULE_DEVICE_TABLE(of, pac1934_of_match);
1598
1599 /*
1600 * using MCHP1930 to be compatible with BIOS ACPI. See example:
1601 * https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ApplicationNotes/ApplicationNotes/PAC1934-Integration-Notes-for-Microsoft-Windows-10-and-Windows-11-Driver-Support-DS00002534.pdf
1602 */
1603 static const struct acpi_device_id pac1934_acpi_match[] = {
1604 { "MCHP1930", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1934] },
1605 { }
1606 };
1607 MODULE_DEVICE_TABLE(acpi, pac1934_acpi_match);
1608
1609 static struct i2c_driver pac1934_driver = {
1610 .driver = {
1611 .name = "pac1934",
1612 .of_match_table = pac1934_of_match,
1613 .acpi_match_table = pac1934_acpi_match
1614 },
1615 .probe = pac1934_probe,
1616 .id_table = pac1934_id,
1617 };
1618
1619 module_i2c_driver(pac1934_driver);
1620
1621 MODULE_AUTHOR("Bogdan Bolocan <bogdan.bolocan@microchip.com>");
1622 MODULE_AUTHOR("Victor Tudose");
1623 MODULE_AUTHOR("Marius Cristea <marius.cristea@microchip.com>");
1624 MODULE_DESCRIPTION("IIO driver for PAC1934 Multi-Channel DC Power/Energy Monitor");
1625 MODULE_LICENSE("GPL");
1626