xref: /linux/drivers/iio/adc/pac1934.c (revision 266aa3b4812e97942a8ce5c7aafa7da059f7b5b8)
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 <asm/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 struct samp_rate_mapping {
231 	u16 samp_rate;
232 	u8 shift2value;
233 };
234 
235 static const unsigned int samp_rate_map_tbl[] = {
236 	[PAC1934_SAMP_1024SPS] = 1024,
237 	[PAC1934_SAMP_256SPS] = 256,
238 	[PAC1934_SAMP_64SPS] = 64,
239 	[PAC1934_SAMP_8SPS] = 8,
240 };
241 
242 static const struct pac1934_features pac1934_chip_config[] = {
243 	[PAC1931] = {
244 	    .phys_channels = 1,
245 	    .name = "pac1931",
246 	},
247 	[PAC1932] = {
248 	    .phys_channels = 2,
249 	    .name = "pac1932",
250 	},
251 	[PAC1933] = {
252 	    .phys_channels = 3,
253 	    .name = "pac1933",
254 	},
255 	[PAC1934] = {
256 	    .phys_channels = 4,
257 	    .name = "pac1934",
258 	},
259 };
260 
261 /**
262  * struct reg_data - data from the registers
263  * @meas_regs:			snapshot of raw measurements registers
264  * @ctrl_regs:			snapshot of control registers
265  * @energy_sec_acc:		snapshot of energy values
266  * @vpower_acc:			accumulated vpower values
267  * @vpower:			snapshot of vpower registers
268  * @vbus:			snapshot of vbus registers
269  * @vbus_avg:			averages of vbus registers
270  * @vsense:			snapshot of vsense registers
271  * @vsense_avg:			averages of vsense registers
272  * @num_enabled_channels:	count of how many chip channels are currently enabled
273  */
274 struct reg_data {
275 	u8	meas_regs[PAC1934_MEAS_REG_LEN];
276 	u8	ctrl_regs[PAC1934_CTRL_REG_LEN];
277 	s64	energy_sec_acc[PAC1934_MAX_NUM_CHANNELS];
278 	s64	vpower_acc[PAC1934_MAX_NUM_CHANNELS];
279 	s32	vpower[PAC1934_MAX_NUM_CHANNELS];
280 	s32	vbus[PAC1934_MAX_NUM_CHANNELS];
281 	s32	vbus_avg[PAC1934_MAX_NUM_CHANNELS];
282 	s32	vsense[PAC1934_MAX_NUM_CHANNELS];
283 	s32	vsense_avg[PAC1934_MAX_NUM_CHANNELS];
284 	u8	num_enabled_channels;
285 };
286 
287 /**
288  * struct pac1934_chip_info - information about the chip
289  * @client:			the i2c-client attached to the device
290  * @lock:			synchronize access to driver's state members
291  * @work_chip_rfsh:		work queue used for refresh commands
292  * @phys_channels:		phys channels count
293  * @active_channels:		array of values, true means that channel is active
294  * @enable_energy:		array of values, true means that channel energy is measured
295  * @bi_dir:			array of bools, true means that channel is bidirectional
296  * @chip_variant:		chip variant
297  * @chip_revision:		chip revision
298  * @shunts:			shunts
299  * @chip_reg_data:		chip reg data
300  * @sample_rate_value:		sampling frequency
301  * @labels:			table with channels labels
302  * @iio_info:			iio_info
303  * @tstamp:			chip's uptime
304  */
305 struct pac1934_chip_info {
306 	struct i2c_client	*client;
307 	struct mutex		lock; /* synchronize access to driver's state members */
308 	struct delayed_work	work_chip_rfsh;
309 	u8			phys_channels;
310 	bool			active_channels[PAC1934_MAX_NUM_CHANNELS];
311 	bool			enable_energy[PAC1934_MAX_NUM_CHANNELS];
312 	bool			bi_dir[PAC1934_MAX_NUM_CHANNELS];
313 	u8			chip_variant;
314 	u8			chip_revision;
315 	u32			shunts[PAC1934_MAX_NUM_CHANNELS];
316 	struct reg_data		chip_reg_data;
317 	s32			sample_rate_value;
318 	char			*labels[PAC1934_MAX_NUM_CHANNELS];
319 	struct iio_info		iio_info;
320 	unsigned long		tstamp;
321 };
322 
323 #define TO_PAC1934_CHIP_INFO(d) container_of(d, struct pac1934_chip_info, work_chip_rfsh)
324 
325 #define PAC1934_VPOWER_ACC_CHANNEL(_index, _si, _address) {			\
326 	.type = IIO_ENERGY,							\
327 	.address = (_address),							\
328 	.indexed = 1,								\
329 	.channel = (_index),							\
330 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW)	|			\
331 			      BIT(IIO_CHAN_INFO_SCALE)	|			\
332 			      BIT(IIO_CHAN_INFO_ENABLE),			\
333 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),		\
334 	.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
335 	.scan_index = (_si),							\
336 	.scan_type = {								\
337 		.sign = 'u',							\
338 		.realbits = 48,							\
339 		.storagebits = 64,						\
340 		.endianness = IIO_CPU,						\
341 	}									\
342 }
343 
344 #define PAC1934_VBUS_CHANNEL(_index, _si, _address) {				\
345 	.type = IIO_VOLTAGE,							\
346 	.address = (_address),							\
347 	.indexed = 1,								\
348 	.channel = (_index),							\
349 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW)	|			\
350 			      BIT(IIO_CHAN_INFO_SCALE),				\
351 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),		\
352 	.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
353 	.scan_index = (_si),							\
354 	.scan_type = {								\
355 		.sign = 'u',							\
356 		.realbits = 16,							\
357 		.storagebits = 16,						\
358 		.endianness = IIO_CPU,						\
359 	}									\
360 }
361 
362 #define PAC1934_VBUS_AVG_CHANNEL(_index, _si, _address) {			\
363 	.type = IIO_VOLTAGE,							\
364 	.address = (_address),							\
365 	.indexed = 1,								\
366 	.channel = (_index),							\
367 	.info_mask_separate = BIT(IIO_CHAN_INFO_AVERAGE_RAW)	|		\
368 			      BIT(IIO_CHAN_INFO_SCALE),				\
369 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),		\
370 	.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
371 	.scan_index = (_si),							\
372 	.scan_type = {								\
373 		.sign = 'u',							\
374 		.realbits = 16,							\
375 		.storagebits = 16,						\
376 		.endianness = IIO_CPU,						\
377 	}									\
378 }
379 
380 #define PAC1934_VSENSE_CHANNEL(_index, _si, _address) {				\
381 	.type = IIO_CURRENT,							\
382 	.address = (_address),							\
383 	.indexed = 1,								\
384 	.channel = (_index),							\
385 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW)	|			\
386 			      BIT(IIO_CHAN_INFO_SCALE),				\
387 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),		\
388 	.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
389 	.scan_index = (_si),							\
390 	.scan_type = {								\
391 		.sign = 'u',							\
392 		.realbits = 16,							\
393 		.storagebits = 16,						\
394 		.endianness = IIO_CPU,						\
395 	}									\
396 }
397 
398 #define PAC1934_VSENSE_AVG_CHANNEL(_index, _si, _address) {			\
399 	.type = IIO_CURRENT,							\
400 	.address = (_address),							\
401 	.indexed = 1,								\
402 	.channel = (_index),							\
403 	.info_mask_separate = BIT(IIO_CHAN_INFO_AVERAGE_RAW)	|		\
404 			      BIT(IIO_CHAN_INFO_SCALE),				\
405 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),		\
406 	.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
407 	.scan_index = (_si),							\
408 	.scan_type = {								\
409 		.sign = 'u',							\
410 		.realbits = 16,							\
411 		.storagebits = 16,						\
412 		.endianness = IIO_CPU,						\
413 	}									\
414 }
415 
416 #define PAC1934_VPOWER_CHANNEL(_index, _si, _address) {				\
417 	.type = IIO_POWER,							\
418 	.address = (_address),							\
419 	.indexed = 1,								\
420 	.channel = (_index),							\
421 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW)	|			\
422 			      BIT(IIO_CHAN_INFO_SCALE),				\
423 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),		\
424 	.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
425 	.scan_index = (_si),							\
426 	.scan_type = {								\
427 		.sign = 'u',							\
428 		.realbits = 28,							\
429 		.storagebits = 32,						\
430 		.shift = 4,							\
431 		.endianness = IIO_CPU,						\
432 	}									\
433 }
434 
435 static const struct iio_chan_spec pac1934_single_channel[] = {
436 	PAC1934_VPOWER_ACC_CHANNEL(0, 0, PAC1934_VPOWER_ACC_1_ADDR),
437 	PAC1934_VPOWER_CHANNEL(0, 0, PAC1934_VPOWER_1_ADDR),
438 	PAC1934_VBUS_CHANNEL(0, 0, PAC1934_VBUS_1_ADDR),
439 	PAC1934_VSENSE_CHANNEL(0, 0, PAC1934_VSENSE_1_ADDR),
440 	PAC1934_VBUS_AVG_CHANNEL(0, 0, PAC1934_VBUS_AVG_1_ADDR),
441 	PAC1934_VSENSE_AVG_CHANNEL(0, 0, PAC1934_VSENSE_AVG_1_ADDR),
442 };
443 
444 /* Low-level I2c functions used to transfer up to 76 bytes at once */
445 static int pac1934_i2c_read(struct i2c_client *client, u8 reg_addr,
446 			    void *databuf, u8 len)
447 {
448 	int ret;
449 	struct i2c_msg msgs[2] = {
450 		{
451 			.addr = client->addr,
452 			.len = 1,
453 			.buf = (u8 *)&reg_addr,
454 		},
455 		{
456 			.addr = client->addr,
457 			.len = len,
458 			.buf = databuf,
459 			.flags = I2C_M_RD
460 		}
461 	};
462 
463 	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
464 	if (ret < 0)
465 		return ret;
466 
467 	return 0;
468 }
469 
470 static int pac1934_get_samp_rate_idx(struct pac1934_chip_info *info,
471 				     u32 new_samp_rate)
472 {
473 	int cnt;
474 
475 	for (cnt = 0; cnt < ARRAY_SIZE(samp_rate_map_tbl); cnt++)
476 		if (new_samp_rate == samp_rate_map_tbl[cnt])
477 			return cnt;
478 
479 	/* not a valid sample rate value */
480 	return -EINVAL;
481 }
482 
483 static ssize_t pac1934_shunt_value_show(struct device *dev,
484 					struct device_attribute *attr,
485 					char *buf)
486 {
487 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
488 	struct pac1934_chip_info *info = iio_priv(indio_dev);
489 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
490 
491 	return sysfs_emit(buf, "%u\n", info->shunts[this_attr->address]);
492 }
493 
494 static ssize_t pac1934_shunt_value_store(struct device *dev,
495 					 struct device_attribute *attr,
496 					 const char *buf, size_t count)
497 {
498 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
499 	struct pac1934_chip_info *info = iio_priv(indio_dev);
500 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
501 	int sh_val;
502 
503 	if (kstrtouint(buf, 10, &sh_val)) {
504 		dev_err(dev, "Shunt value is not valid\n");
505 		return -EINVAL;
506 	}
507 
508 	scoped_guard(mutex, &info->lock)
509 		info->shunts[this_attr->address] = sh_val;
510 
511 	return count;
512 }
513 
514 static int pac1934_read_avail(struct iio_dev *indio_dev,
515 			      struct iio_chan_spec const *channel,
516 			      const int **vals, int *type, int *length, long mask)
517 {
518 	switch (mask) {
519 	case IIO_CHAN_INFO_SAMP_FREQ:
520 		*type = IIO_VAL_INT;
521 		*vals = samp_rate_map_tbl;
522 		*length = ARRAY_SIZE(samp_rate_map_tbl);
523 		return IIO_AVAIL_LIST;
524 	}
525 
526 	return -EINVAL;
527 }
528 
529 static int pac1934_send_refresh(struct pac1934_chip_info *info,
530 				u8 refresh_cmd, u32 wait_time)
531 {
532 	/* this function only sends REFRESH or REFRESH_V */
533 	struct i2c_client *client = info->client;
534 	int ret;
535 	u8 bidir_reg;
536 	bool revision_bug = false;
537 
538 	if (info->chip_revision == 2 || info->chip_revision == 3) {
539 		/*
540 		 * chip rev 2 and 3 bug workaround
541 		 * see: PAC1934 Family Data Sheet Errata DS80000836A.pdf
542 		 */
543 		revision_bug = true;
544 
545 		bidir_reg =
546 			FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDI_MASK, info->bi_dir[0]) |
547 			FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDI_MASK, info->bi_dir[1]) |
548 			FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDI_MASK, info->bi_dir[2]) |
549 			FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDI_MASK, info->bi_dir[3]) |
550 			FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDV_MASK, info->bi_dir[0]) |
551 			FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDV_MASK, info->bi_dir[1]) |
552 			FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDV_MASK, info->bi_dir[2]) |
553 			FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDV_MASK, info->bi_dir[3]);
554 
555 		ret = i2c_smbus_write_byte_data(client,
556 						PAC1934_CTRL_STAT_REGS_ADDR +
557 						PAC1934_NEG_PWR_REG_OFF,
558 						bidir_reg);
559 		if (ret)
560 			return ret;
561 	}
562 
563 	ret = i2c_smbus_write_byte(client, refresh_cmd);
564 	if (ret) {
565 		dev_err(&client->dev, "%s - cannot send 0x%02X\n",
566 			__func__, refresh_cmd);
567 		return ret;
568 	}
569 
570 	if (revision_bug) {
571 		/*
572 		 * chip rev 2 and 3 bug workaround - write again the same
573 		 * register write the updated registers back
574 		 */
575 		ret = i2c_smbus_write_byte_data(client,
576 						PAC1934_CTRL_STAT_REGS_ADDR +
577 						PAC1934_NEG_PWR_REG_OFF, bidir_reg);
578 		if (ret)
579 			return ret;
580 	}
581 
582 	/* register data retrieval timestamp */
583 	info->tstamp = jiffies;
584 
585 	/* wait till the data is available */
586 	usleep_range(wait_time, wait_time + 100);
587 
588 	return ret;
589 }
590 
591 static int pac1934_reg_snapshot(struct pac1934_chip_info *info,
592 				bool do_refresh, u8 refresh_cmd, u32 wait_time)
593 {
594 	int ret;
595 	struct i2c_client *client = info->client;
596 	u8 samp_shift, ctrl_regs_tmp;
597 	u8 *offset_reg_data_p;
598 	u16 tmp_value;
599 	u32 samp_rate, cnt, tmp;
600 	s64 curr_energy, inc;
601 	u64 tmp_energy;
602 	struct reg_data *reg_data;
603 
604 	guard(mutex)(&info->lock);
605 
606 	if (do_refresh) {
607 		ret = pac1934_send_refresh(info, refresh_cmd, wait_time);
608 		if (ret < 0) {
609 			dev_err(&client->dev,
610 				"%s - cannot send refresh\n",
611 				__func__);
612 			return ret;
613 		}
614 	}
615 
616 	ret = i2c_smbus_read_i2c_block_data(client, PAC1934_CTRL_STAT_REGS_ADDR,
617 					    PAC1934_CTRL_REG_LEN,
618 					    (u8 *)info->chip_reg_data.ctrl_regs);
619 	if (ret < 0) {
620 		dev_err(&client->dev,
621 			"%s - cannot read ctrl/status registers\n",
622 			__func__);
623 		return ret;
624 	}
625 
626 	reg_data = &info->chip_reg_data;
627 
628 	/* read the data registers */
629 	ret = pac1934_i2c_read(client, PAC1934_ACC_COUNT_REG_ADDR,
630 			       (u8 *)reg_data->meas_regs, PAC1934_MEAS_REG_LEN);
631 	if (ret) {
632 		dev_err(&client->dev,
633 			"%s - cannot read ACC_COUNT register: %d:%d\n",
634 			__func__, ret, PAC1934_MEAS_REG_LEN);
635 		return ret;
636 	}
637 
638 	/* see how much shift is required by the sample rate */
639 	samp_rate = samp_rate_map_tbl[((reg_data->ctrl_regs[PAC1934_CTRL_LAT_REG_OFF]) >> 6)];
640 	samp_shift = get_count_order(samp_rate);
641 
642 	ctrl_regs_tmp = reg_data->ctrl_regs[PAC1934_CHANNEL_DIS_LAT_REG_OFF];
643 	offset_reg_data_p = &reg_data->meas_regs[PAC1934_ACC_REG_LEN];
644 
645 	/* start with VPOWER_ACC */
646 	for (cnt = 0; cnt < info->phys_channels; cnt++) {
647 		/* check if the channel is active, skip all fields if disabled */
648 		if ((ctrl_regs_tmp << cnt) & 0x80)
649 			continue;
650 
651 		/* skip if the energy accumulation is disabled */
652 		if (info->enable_energy[cnt]) {
653 			curr_energy = info->chip_reg_data.energy_sec_acc[cnt];
654 
655 			tmp_energy = get_unaligned_be48(offset_reg_data_p);
656 
657 			if (info->bi_dir[cnt])
658 				reg_data->vpower_acc[cnt] = sign_extend64(tmp_energy, 47);
659 			else
660 				reg_data->vpower_acc[cnt] = tmp_energy;
661 
662 			/*
663 			 * compute the scaled to 1 second accumulated energy value;
664 			 * energy accumulator scaled to 1sec = VPOWER_ACC/2^samp_shift
665 			 * the chip's sampling rate is 2^samp_shift samples/sec
666 			 */
667 			inc = (reg_data->vpower_acc[cnt] >> samp_shift);
668 
669 			/* add the power_acc field */
670 			curr_energy += inc;
671 
672 			clamp(curr_energy, PAC_193X_MIN_POWER_ACC, PAC_193X_MAX_POWER_ACC);
673 
674 			reg_data->energy_sec_acc[cnt] = curr_energy;
675 		}
676 
677 		offset_reg_data_p += PAC1934_VPOWER_ACC_REG_LEN;
678 	}
679 
680 	/* continue with VBUS */
681 	for (cnt = 0; cnt < info->phys_channels; cnt++) {
682 		if ((ctrl_regs_tmp << cnt) & 0x80)
683 			continue;
684 
685 		tmp_value = get_unaligned_be16(offset_reg_data_p);
686 
687 		if (info->bi_dir[cnt])
688 			reg_data->vbus[cnt] = sign_extend32((u32)(tmp_value), 15);
689 		else
690 			reg_data->vbus[cnt] = tmp_value;
691 
692 		offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
693 	}
694 
695 	/* VSENSE */
696 	for (cnt = 0; cnt < info->phys_channels; cnt++) {
697 		if ((ctrl_regs_tmp << cnt) & 0x80)
698 			continue;
699 
700 		tmp_value = get_unaligned_be16(offset_reg_data_p);
701 
702 		if (info->bi_dir[cnt])
703 			reg_data->vsense[cnt] = sign_extend32((u32)(tmp_value), 15);
704 		else
705 			reg_data->vsense[cnt] = tmp_value;
706 
707 		offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
708 	}
709 
710 	/* VBUS_AVG */
711 	for (cnt = 0; cnt < info->phys_channels; cnt++) {
712 		if ((ctrl_regs_tmp << cnt) & 0x80)
713 			continue;
714 
715 		tmp_value = get_unaligned_be16(offset_reg_data_p);
716 
717 		if (info->bi_dir[cnt])
718 			reg_data->vbus_avg[cnt] = sign_extend32((u32)(tmp_value), 15);
719 		else
720 			reg_data->vbus_avg[cnt] = tmp_value;
721 
722 		offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
723 	}
724 
725 	/* VSENSE_AVG */
726 	for (cnt = 0; cnt < info->phys_channels; cnt++) {
727 		if ((ctrl_regs_tmp << cnt) & 0x80)
728 			continue;
729 
730 		tmp_value = get_unaligned_be16(offset_reg_data_p);
731 
732 		if (info->bi_dir[cnt])
733 			reg_data->vsense_avg[cnt] = sign_extend32((u32)(tmp_value), 15);
734 		else
735 			reg_data->vsense_avg[cnt] = tmp_value;
736 
737 		offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
738 	}
739 
740 	/* VPOWER */
741 	for (cnt = 0; cnt < info->phys_channels; cnt++) {
742 		if ((ctrl_regs_tmp << cnt) & 0x80)
743 			continue;
744 
745 		tmp = get_unaligned_be32(offset_reg_data_p) >> 4;
746 
747 		if (info->bi_dir[cnt])
748 			reg_data->vpower[cnt] = sign_extend32(tmp, 27);
749 		else
750 			reg_data->vpower[cnt] = tmp;
751 
752 		offset_reg_data_p += PAC1934_VPOWER_REG_LEN;
753 	}
754 
755 	return 0;
756 }
757 
758 static int pac1934_retrieve_data(struct pac1934_chip_info *info,
759 				 u32 wait_time)
760 {
761 	int ret = 0;
762 
763 	/*
764 	 * check if the minimal elapsed time has passed and if so,
765 	 * re-read the chip, otherwise the cached info is just fine
766 	 */
767 	if (time_after(jiffies, info->tstamp + msecs_to_jiffies(PAC1934_MIN_POLLING_TIME_MS))) {
768 		ret = pac1934_reg_snapshot(info, true, PAC1934_REFRESH_REG_ADDR,
769 					   wait_time);
770 
771 		/*
772 		 * Re-schedule the work for the read registers on timeout
773 		 * (to prevent chip registers saturation)
774 		 */
775 		mod_delayed_work(system_wq, &info->work_chip_rfsh,
776 				 msecs_to_jiffies(PAC1934_MAX_RFSH_LIMIT_MS));
777 	}
778 
779 	return ret;
780 }
781 
782 static int pac1934_read_raw(struct iio_dev *indio_dev,
783 			    struct iio_chan_spec const *chan, int *val,
784 			    int *val2, long mask)
785 {
786 	struct pac1934_chip_info *info = iio_priv(indio_dev);
787 	s64 curr_energy;
788 	int ret, channel = chan->channel - 1;
789 
790 	/*
791 	 * For AVG the index should be between 5 to 8.
792 	 * To calculate PAC1934_CH_VOLTAGE_AVERAGE,
793 	 * respectively PAC1934_CH_CURRENT real index, we need
794 	 * to remove the added offset (PAC1934_MAX_NUM_CHANNELS).
795 	 */
796 	if (channel >= PAC1934_MAX_NUM_CHANNELS)
797 		channel = channel - PAC1934_MAX_NUM_CHANNELS;
798 
799 	ret = pac1934_retrieve_data(info, PAC1934_MIN_UPDATE_WAIT_TIME_US);
800 	if (ret < 0)
801 		return ret;
802 
803 	switch (mask) {
804 	case IIO_CHAN_INFO_RAW:
805 		switch (chan->type) {
806 		case IIO_VOLTAGE:
807 			*val = info->chip_reg_data.vbus[channel];
808 			return IIO_VAL_INT;
809 		case IIO_CURRENT:
810 			*val = info->chip_reg_data.vsense[channel];
811 			return IIO_VAL_INT;
812 		case IIO_POWER:
813 			*val = info->chip_reg_data.vpower[channel];
814 			return IIO_VAL_INT;
815 		case IIO_ENERGY:
816 			curr_energy = info->chip_reg_data.energy_sec_acc[channel];
817 			*val = (u32)curr_energy;
818 			*val2 = (u32)(curr_energy >> 32);
819 			return IIO_VAL_INT_64;
820 		default:
821 			return -EINVAL;
822 		}
823 	case IIO_CHAN_INFO_AVERAGE_RAW:
824 		switch (chan->type) {
825 		case IIO_VOLTAGE:
826 			*val = info->chip_reg_data.vbus_avg[channel];
827 			return IIO_VAL_INT;
828 		case IIO_CURRENT:
829 			*val = info->chip_reg_data.vsense_avg[channel];
830 			return IIO_VAL_INT;
831 		default:
832 			return -EINVAL;
833 		}
834 	case IIO_CHAN_INFO_SCALE:
835 		switch (chan->address) {
836 		/* Voltages - scale for millivolts */
837 		case PAC1934_VBUS_1_ADDR:
838 		case PAC1934_VBUS_2_ADDR:
839 		case PAC1934_VBUS_3_ADDR:
840 		case PAC1934_VBUS_4_ADDR:
841 		case PAC1934_VBUS_AVG_1_ADDR:
842 		case PAC1934_VBUS_AVG_2_ADDR:
843 		case PAC1934_VBUS_AVG_3_ADDR:
844 		case PAC1934_VBUS_AVG_4_ADDR:
845 			*val = PAC1934_VOLTAGE_MILLIVOLTS_MAX;
846 			if (chan->scan_type.sign == 'u')
847 				*val2 = PAC1934_VOLTAGE_U_RES;
848 			else
849 				*val2 = PAC1934_VOLTAGE_S_RES;
850 			return IIO_VAL_FRACTIONAL_LOG2;
851 		/*
852 		 * Currents - scale for mA - depends on the
853 		 * channel's shunt value
854 		 * (100mV * 1000000) / (2^16 * shunt(uohm))
855 		 */
856 		case PAC1934_VSENSE_1_ADDR:
857 		case PAC1934_VSENSE_2_ADDR:
858 		case PAC1934_VSENSE_3_ADDR:
859 		case PAC1934_VSENSE_4_ADDR:
860 		case PAC1934_VSENSE_AVG_1_ADDR:
861 		case PAC1934_VSENSE_AVG_2_ADDR:
862 		case PAC1934_VSENSE_AVG_3_ADDR:
863 		case PAC1934_VSENSE_AVG_4_ADDR:
864 			*val = PAC1934_MAX_VSENSE_RSHIFTED_BY_16B;
865 			if (chan->scan_type.sign == 'u')
866 				*val2 = info->shunts[channel];
867 			else
868 				*val2 = info->shunts[channel] >> 1;
869 			return IIO_VAL_FRACTIONAL;
870 		/*
871 		 * Power - uW - it will use the combined scale
872 		 * for current and voltage
873 		 * current(mA) * voltage(mV) = power (uW)
874 		 */
875 		case PAC1934_VPOWER_1_ADDR:
876 		case PAC1934_VPOWER_2_ADDR:
877 		case PAC1934_VPOWER_3_ADDR:
878 		case PAC1934_VPOWER_4_ADDR:
879 			*val = PAC1934_MAX_VPOWER_RSHIFTED_BY_28B;
880 			if (chan->scan_type.sign == 'u')
881 				*val2 = info->shunts[channel];
882 			else
883 				*val2 = info->shunts[channel] >> 1;
884 			return IIO_VAL_FRACTIONAL;
885 		case PAC1934_VPOWER_ACC_1_ADDR:
886 		case PAC1934_VPOWER_ACC_2_ADDR:
887 		case PAC1934_VPOWER_ACC_3_ADDR:
888 		case PAC1934_VPOWER_ACC_4_ADDR:
889 			/*
890 			 * expresses the 32 bit scale value here compute
891 			 * the scale for energy (miliWatt-second or miliJoule)
892 			 */
893 			*val = PAC1934_SCALE_CONSTANT;
894 
895 			if (chan->scan_type.sign == 'u')
896 				*val2 = info->shunts[channel];
897 			else
898 				*val2 = info->shunts[channel] >> 1;
899 			return IIO_VAL_FRACTIONAL;
900 		default:
901 			return -EINVAL;
902 		}
903 	case IIO_CHAN_INFO_SAMP_FREQ:
904 		*val = info->sample_rate_value;
905 		return IIO_VAL_INT;
906 	case IIO_CHAN_INFO_ENABLE:
907 		*val = info->enable_energy[channel];
908 		return IIO_VAL_INT;
909 	default:
910 		return -EINVAL;
911 	}
912 }
913 
914 static int pac1934_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
915 			     int val, int val2, long mask)
916 {
917 	struct pac1934_chip_info *info = iio_priv(indio_dev);
918 	struct i2c_client *client = info->client;
919 	int ret = -EINVAL;
920 	s32 old_samp_rate;
921 	u8 ctrl_reg;
922 
923 	switch (mask) {
924 	case IIO_CHAN_INFO_SAMP_FREQ:
925 		ret = pac1934_get_samp_rate_idx(info, val);
926 		if (ret < 0)
927 			return ret;
928 
929 		/* write the new sampling value and trigger a snapshot(incl refresh) */
930 		scoped_guard(mutex, &info->lock) {
931 			ctrl_reg = FIELD_PREP(PAC1934_CRTL_SAMPLE_RATE_MASK, ret);
932 			ret = i2c_smbus_write_byte_data(client, PAC1934_CTRL_REG_ADDR, ctrl_reg);
933 			if (ret) {
934 				dev_err(&client->dev,
935 					"%s - can't update sample rate\n",
936 					__func__);
937 				return ret;
938 			}
939 		}
940 
941 		old_samp_rate = info->sample_rate_value;
942 		info->sample_rate_value = val;
943 
944 		/*
945 		 * now, force a snapshot with refresh - call retrieve
946 		 * data in order to update the refresh timer
947 		 * alter the timestamp in order to force trigger a
948 		 * register snapshot and a timestamp update
949 		 */
950 		info->tstamp -= msecs_to_jiffies(PAC1934_MIN_POLLING_TIME_MS);
951 		ret = pac1934_retrieve_data(info, (1024 / old_samp_rate) * 1000);
952 		if (ret < 0) {
953 			dev_err(&client->dev,
954 				"%s - cannot snapshot ctrl and measurement regs\n",
955 				__func__);
956 			return ret;
957 		}
958 
959 		return 0;
960 	case IIO_CHAN_INFO_ENABLE:
961 		scoped_guard(mutex, &info->lock) {
962 			info->enable_energy[chan->channel - 1] = val ? true : false;
963 			if (!val)
964 				info->chip_reg_data.energy_sec_acc[chan->channel - 1] = 0;
965 		}
966 
967 		return 0;
968 	default:
969 		return -EINVAL;
970 	}
971 }
972 
973 static int pac1934_read_label(struct iio_dev *indio_dev,
974 			      struct iio_chan_spec const *chan, char *label)
975 {
976 	struct pac1934_chip_info *info = iio_priv(indio_dev);
977 
978 	switch (chan->address) {
979 	case PAC1934_VBUS_1_ADDR:
980 	case PAC1934_VBUS_2_ADDR:
981 	case PAC1934_VBUS_3_ADDR:
982 	case PAC1934_VBUS_4_ADDR:
983 		return sysfs_emit(label, "%s_VBUS_%d\n",
984 				  info->labels[chan->scan_index],
985 				  chan->scan_index + 1);
986 	case PAC1934_VBUS_AVG_1_ADDR:
987 	case PAC1934_VBUS_AVG_2_ADDR:
988 	case PAC1934_VBUS_AVG_3_ADDR:
989 	case PAC1934_VBUS_AVG_4_ADDR:
990 		return sysfs_emit(label, "%s_VBUS_AVG_%d\n",
991 				  info->labels[chan->scan_index],
992 				  chan->scan_index + 1);
993 	case PAC1934_VSENSE_1_ADDR:
994 	case PAC1934_VSENSE_2_ADDR:
995 	case PAC1934_VSENSE_3_ADDR:
996 	case PAC1934_VSENSE_4_ADDR:
997 		return sysfs_emit(label, "%s_IBUS_%d\n",
998 				  info->labels[chan->scan_index],
999 				  chan->scan_index + 1);
1000 	case PAC1934_VSENSE_AVG_1_ADDR:
1001 	case PAC1934_VSENSE_AVG_2_ADDR:
1002 	case PAC1934_VSENSE_AVG_3_ADDR:
1003 	case PAC1934_VSENSE_AVG_4_ADDR:
1004 		return sysfs_emit(label, "%s_IBUS_AVG_%d\n",
1005 				  info->labels[chan->scan_index],
1006 				  chan->scan_index + 1);
1007 	case PAC1934_VPOWER_1_ADDR:
1008 	case PAC1934_VPOWER_2_ADDR:
1009 	case PAC1934_VPOWER_3_ADDR:
1010 	case PAC1934_VPOWER_4_ADDR:
1011 		return sysfs_emit(label, "%s_POWER_%d\n",
1012 				  info->labels[chan->scan_index],
1013 				  chan->scan_index + 1);
1014 	case PAC1934_VPOWER_ACC_1_ADDR:
1015 	case PAC1934_VPOWER_ACC_2_ADDR:
1016 	case PAC1934_VPOWER_ACC_3_ADDR:
1017 	case PAC1934_VPOWER_ACC_4_ADDR:
1018 		return sysfs_emit(label, "%s_ENERGY_%d\n",
1019 				  info->labels[chan->scan_index],
1020 				  chan->scan_index + 1);
1021 	}
1022 
1023 	return 0;
1024 }
1025 
1026 static void pac1934_work_periodic_rfsh(struct work_struct *work)
1027 {
1028 	struct pac1934_chip_info *info = TO_PAC1934_CHIP_INFO((struct delayed_work *)work);
1029 	struct device *dev = &info->client->dev;
1030 
1031 	dev_dbg(dev, "%s - Periodic refresh\n", __func__);
1032 
1033 	/* do a REFRESH, then read */
1034 	pac1934_reg_snapshot(info, true, PAC1934_REFRESH_REG_ADDR,
1035 			     PAC1934_MIN_UPDATE_WAIT_TIME_US);
1036 
1037 	schedule_delayed_work(&info->work_chip_rfsh,
1038 			      msecs_to_jiffies(PAC1934_MAX_RFSH_LIMIT_MS));
1039 }
1040 
1041 static int pac1934_read_revision(struct pac1934_chip_info *info, u8 *buf)
1042 {
1043 	int ret;
1044 	struct i2c_client *client = info->client;
1045 
1046 	ret = i2c_smbus_read_i2c_block_data(client, PAC1934_PID_REG_ADDR,
1047 					    PAC1934_ID_REG_LEN,
1048 					    buf);
1049 	if (ret < 0) {
1050 		dev_err(&client->dev, "cannot read revision\n");
1051 		return ret;
1052 	}
1053 
1054 	return 0;
1055 }
1056 
1057 static int pac1934_chip_identify(struct pac1934_chip_info *info)
1058 {
1059 	u8 rev_info[PAC1934_ID_REG_LEN];
1060 	struct device *dev = &info->client->dev;
1061 	int ret = 0;
1062 
1063 	ret = pac1934_read_revision(info, (u8 *)rev_info);
1064 	if (ret)
1065 		return ret;
1066 
1067 	info->chip_variant = rev_info[PAC1934_PID_IDX];
1068 	info->chip_revision = rev_info[PAC1934_RID_IDX];
1069 
1070 	dev_dbg(dev, "Chip variant: 0x%02X\n", info->chip_variant);
1071 	dev_dbg(dev, "Chip revision: 0x%02X\n", info->chip_revision);
1072 
1073 	switch (info->chip_variant) {
1074 	case PAC1934_PID:
1075 		return PAC1934;
1076 	case PAC1933_PID:
1077 		return PAC1933;
1078 	case PAC1932_PID:
1079 		return PAC1932;
1080 	case PAC1931_PID:
1081 		return PAC1931;
1082 	default:
1083 		return -EINVAL;
1084 	}
1085 }
1086 
1087 /*
1088  * documentation related to the ACPI device definition
1089  * https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ApplicationNotes/ApplicationNotes/PAC1934-Integration-Notes-for-Microsoft-Windows-10-and-Windows-11-Driver-Support-DS00002534.pdf
1090  */
1091 static int pac1934_acpi_parse_channel_config(struct i2c_client *client,
1092 					     struct pac1934_chip_info *info)
1093 {
1094 	acpi_handle handle;
1095 	union acpi_object *rez;
1096 	struct device *dev = &client->dev;
1097 	unsigned short bi_dir_mask;
1098 	int idx, i;
1099 	guid_t guid;
1100 
1101 	handle = ACPI_HANDLE(dev);
1102 
1103 	guid_parse(PAC1934_DSM_UUID, &guid);
1104 
1105 	rez = acpi_evaluate_dsm(handle, &guid, 0, PAC1934_ACPI_GET_NAMES_AND_MOHMS_VALS, NULL);
1106 	if (!rez)
1107 		return -EINVAL;
1108 
1109 	for (i = 0; i < rez->package.count; i += 2) {
1110 		idx = i / 2;
1111 		info->labels[idx] =
1112 			devm_kmemdup(dev, rez->package.elements[i].string.pointer,
1113 				     (size_t)rez->package.elements[i].string.length + 1,
1114 				     GFP_KERNEL);
1115 		info->labels[idx][rez->package.elements[i].string.length] = '\0';
1116 		info->shunts[idx] = rez->package.elements[i + 1].integer.value * 1000;
1117 		info->active_channels[idx] = (info->shunts[idx] != 0);
1118 	}
1119 
1120 	ACPI_FREE(rez);
1121 
1122 	rez = acpi_evaluate_dsm(handle, &guid, 1, PAC1934_ACPI_GET_UOHMS_VALS, NULL);
1123 	if (!rez) {
1124 		/*
1125 		 * initializing with default values
1126 		 * we assume all channels are unidirectional(the mask is zero)
1127 		 * and assign the default sampling rate
1128 		 */
1129 		info->sample_rate_value = PAC1934_DEFAULT_CHIP_SAMP_SPEED_HZ;
1130 		return 0;
1131 	}
1132 
1133 	for (i = 0; i < rez->package.count; i++) {
1134 		idx = i;
1135 		info->shunts[idx] = rez->package.elements[i].integer.value;
1136 		info->active_channels[idx] = (info->shunts[idx] != 0);
1137 	}
1138 
1139 	ACPI_FREE(rez);
1140 
1141 	rez = acpi_evaluate_dsm(handle, &guid, 1, PAC1934_ACPI_GET_BIPOLAR_SETTINGS, NULL);
1142 	if (!rez)
1143 		return -EINVAL;
1144 
1145 	bi_dir_mask = rez->package.elements[0].integer.value;
1146 	info->bi_dir[0] = ((bi_dir_mask & (1 << 3)) | (bi_dir_mask & (1 << 7))) != 0;
1147 	info->bi_dir[1] = ((bi_dir_mask & (1 << 2)) | (bi_dir_mask & (1 << 6))) != 0;
1148 	info->bi_dir[2] = ((bi_dir_mask & (1 << 1)) | (bi_dir_mask & (1 << 5))) != 0;
1149 	info->bi_dir[3] = ((bi_dir_mask & (1 << 0)) | (bi_dir_mask & (1 << 4))) != 0;
1150 
1151 	ACPI_FREE(rez);
1152 
1153 	rez = acpi_evaluate_dsm(handle, &guid, 1, PAC1934_ACPI_GET_SAMP, NULL);
1154 	if (!rez)
1155 		return -EINVAL;
1156 
1157 	info->sample_rate_value = rez->package.elements[0].integer.value;
1158 
1159 	ACPI_FREE(rez);
1160 
1161 	return 0;
1162 }
1163 
1164 static int pac1934_fw_parse_channel_config(struct i2c_client *client,
1165 					   struct pac1934_chip_info *info)
1166 {
1167 	struct device *dev = &client->dev;
1168 	unsigned int current_channel;
1169 	int idx, ret;
1170 
1171 	info->sample_rate_value = 1024;
1172 	current_channel = 1;
1173 
1174 	device_for_each_child_node_scoped(dev, node) {
1175 		ret = fwnode_property_read_u32(node, "reg", &idx);
1176 		if (ret)
1177 			return dev_err_probe(dev, ret,
1178 					     "reading invalid channel index\n");
1179 
1180 		/* adjust idx to match channel index (1 to 4) from the datasheet */
1181 		idx--;
1182 
1183 		if (current_channel >= (info->phys_channels + 1) ||
1184 		    idx >= info->phys_channels || idx < 0)
1185 			return dev_err_probe(dev, -EINVAL,
1186 					     "%s: invalid channel_index %d value\n",
1187 					     fwnode_get_name(node), idx);
1188 
1189 		/* enable channel */
1190 		info->active_channels[idx] = true;
1191 
1192 		ret = fwnode_property_read_u32(node, "shunt-resistor-micro-ohms",
1193 					       &info->shunts[idx]);
1194 		if (ret)
1195 			return dev_err_probe(dev, ret,
1196 					     "%s: invalid shunt-resistor value: %d\n",
1197 					     fwnode_get_name(node), info->shunts[idx]);
1198 
1199 		if (fwnode_property_present(node, "label")) {
1200 			ret = fwnode_property_read_string(node, "label",
1201 							  (const char **)&info->labels[idx]);
1202 			if (ret)
1203 				return dev_err_probe(dev, ret,
1204 						     "%s: invalid rail-name value\n",
1205 						     fwnode_get_name(node));
1206 		}
1207 
1208 		info->bi_dir[idx] = fwnode_property_read_bool(node, "bipolar");
1209 
1210 		current_channel++;
1211 	}
1212 
1213 	return 0;
1214 }
1215 
1216 static void pac1934_cancel_delayed_work(void *dwork)
1217 {
1218 	cancel_delayed_work_sync(dwork);
1219 }
1220 
1221 static int pac1934_chip_configure(struct pac1934_chip_info *info)
1222 {
1223 	int cnt, ret;
1224 	struct i2c_client *client = info->client;
1225 	u8 regs[PAC1934_CTRL_STATUS_INFO_LEN], idx, ctrl_reg;
1226 	u32 wait_time;
1227 
1228 	info->chip_reg_data.num_enabled_channels = 0;
1229 	for (cnt = 0;  cnt < info->phys_channels; cnt++) {
1230 		if (info->active_channels[cnt])
1231 			info->chip_reg_data.num_enabled_channels++;
1232 	}
1233 
1234 	/*
1235 	 * read whatever information was gathered before the driver was loaded
1236 	 * establish which channels are enabled/disabled and then establish the
1237 	 * information retrieval mode (using SKIP or no).
1238 	 * Read the chip ID values
1239 	 */
1240 	ret = i2c_smbus_read_i2c_block_data(client, PAC1934_CTRL_STAT_REGS_ADDR,
1241 					    ARRAY_SIZE(regs),
1242 					    (u8 *)regs);
1243 	if (ret < 0) {
1244 		dev_err_probe(&client->dev, ret,
1245 			      "%s - cannot read regs from 0x%02X\n",
1246 			      __func__, PAC1934_CTRL_STAT_REGS_ADDR);
1247 		return ret;
1248 	}
1249 
1250 	/* write the CHANNEL_DIS and the NEG_PWR registers */
1251 	regs[PAC1934_CHANNEL_DIS_REG_OFF] =
1252 		FIELD_PREP(PAC1934_CHAN_DIS_CH1_OFF_MASK, info->active_channels[0] ? 0 : 1) |
1253 		FIELD_PREP(PAC1934_CHAN_DIS_CH2_OFF_MASK, info->active_channels[1] ? 0 : 1) |
1254 		FIELD_PREP(PAC1934_CHAN_DIS_CH3_OFF_MASK, info->active_channels[2] ? 0 : 1) |
1255 		FIELD_PREP(PAC1934_CHAN_DIS_CH4_OFF_MASK, info->active_channels[3] ? 0 : 1) |
1256 		FIELD_PREP(PAC1934_SMBUS_TIMEOUT_MASK, 0) |
1257 		FIELD_PREP(PAC1934_SMBUS_BYTECOUNT_MASK, 0) |
1258 		FIELD_PREP(PAC1934_SMBUS_NO_SKIP_MASK, 0);
1259 
1260 	regs[PAC1934_NEG_PWR_REG_OFF] =
1261 		FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDI_MASK, info->bi_dir[0]) |
1262 		FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDI_MASK, info->bi_dir[1]) |
1263 		FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDI_MASK, info->bi_dir[2]) |
1264 		FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDI_MASK, info->bi_dir[3]) |
1265 		FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDV_MASK, info->bi_dir[0]) |
1266 		FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDV_MASK, info->bi_dir[1]) |
1267 		FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDV_MASK, info->bi_dir[2]) |
1268 		FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDV_MASK, info->bi_dir[3]);
1269 
1270 	/* no SLOW triggered REFRESH, clear POR */
1271 	regs[PAC1934_SLOW_REG_OFF] = 0;
1272 
1273 	ret =  i2c_smbus_write_block_data(client, PAC1934_CTRL_STAT_REGS_ADDR,
1274 					  ARRAY_SIZE(regs), (u8 *)regs);
1275 	if (ret)
1276 		return ret;
1277 
1278 	/* Default sampling rate */
1279 	ctrl_reg = FIELD_PREP(PAC1934_CRTL_SAMPLE_RATE_MASK, PAC1934_SAMP_1024SPS);
1280 
1281 	ret = i2c_smbus_write_byte_data(client, PAC1934_CTRL_REG_ADDR, ctrl_reg);
1282 	if (ret)
1283 		return ret;
1284 
1285 	/*
1286 	 * send a REFRESH to the chip, so the new settings take place
1287 	 * as well as resetting the accumulators
1288 	 */
1289 	ret = i2c_smbus_write_byte(client, PAC1934_REFRESH_REG_ADDR);
1290 	if (ret) {
1291 		dev_err(&client->dev,
1292 			"%s - cannot send 0x%02X\n",
1293 			__func__, PAC1934_REFRESH_REG_ADDR);
1294 		return ret;
1295 	}
1296 
1297 	/*
1298 	 * get the current(in the chip) sampling speed and compute the
1299 	 * required timeout based on its value
1300 	 * the timeout is 1/sampling_speed
1301 	 */
1302 	idx = regs[PAC1934_CTRL_ACT_REG_OFF] >> PAC1934_SAMPLE_RATE_SHIFT;
1303 	wait_time = (1024 / samp_rate_map_tbl[idx]) * 1000;
1304 
1305 	/*
1306 	 * wait the maximum amount of time to be on the safe side
1307 	 * the maximum wait time is for 8sps
1308 	 */
1309 	usleep_range(wait_time, wait_time + 100);
1310 
1311 	INIT_DELAYED_WORK(&info->work_chip_rfsh, pac1934_work_periodic_rfsh);
1312 	/* Setup the latest moment for reading the regs before saturation */
1313 	schedule_delayed_work(&info->work_chip_rfsh,
1314 			      msecs_to_jiffies(PAC1934_MAX_RFSH_LIMIT_MS));
1315 
1316 	return devm_add_action_or_reset(&client->dev, pac1934_cancel_delayed_work,
1317 					&info->work_chip_rfsh);
1318 }
1319 
1320 static int pac1934_prep_iio_channels(struct pac1934_chip_info *info, struct iio_dev *indio_dev)
1321 {
1322 	struct iio_chan_spec *ch_sp;
1323 	int channel_size, attribute_count, cnt;
1324 	void *dyn_ch_struct, *tmp_data;
1325 	struct device *dev = &info->client->dev;
1326 
1327 	/* find out dynamically how many IIO channels we need */
1328 	attribute_count = 0;
1329 	channel_size = 0;
1330 	for (cnt = 0; cnt < info->phys_channels; cnt++) {
1331 		if (!info->active_channels[cnt])
1332 			continue;
1333 
1334 		/* add the size of the properties of one chip physical channel */
1335 		channel_size += sizeof(pac1934_single_channel);
1336 		/* count how many enabled channels we have */
1337 		attribute_count += ARRAY_SIZE(pac1934_single_channel);
1338 		dev_dbg(dev, ":%s: Channel %d active\n", __func__, cnt + 1);
1339 	}
1340 
1341 	dyn_ch_struct = devm_kzalloc(dev, channel_size, GFP_KERNEL);
1342 	if (!dyn_ch_struct)
1343 		return -EINVAL;
1344 
1345 	tmp_data = dyn_ch_struct;
1346 
1347 	/* populate the dynamic channels and make all the adjustments */
1348 	for (cnt = 0; cnt < info->phys_channels; cnt++) {
1349 		if (!info->active_channels[cnt])
1350 			continue;
1351 
1352 		memcpy(tmp_data, pac1934_single_channel, sizeof(pac1934_single_channel));
1353 		ch_sp = (struct iio_chan_spec *)tmp_data;
1354 		ch_sp[PAC1934_CH_ENERGY].channel = cnt + 1;
1355 		ch_sp[PAC1934_CH_ENERGY].scan_index = cnt;
1356 		ch_sp[PAC1934_CH_ENERGY].address = cnt + PAC1934_VPOWER_ACC_1_ADDR;
1357 		ch_sp[PAC1934_CH_POWER].channel = cnt + 1;
1358 		ch_sp[PAC1934_CH_POWER].scan_index = cnt;
1359 		ch_sp[PAC1934_CH_POWER].address = cnt + PAC1934_VPOWER_1_ADDR;
1360 		ch_sp[PAC1934_CH_VOLTAGE].channel = cnt + 1;
1361 		ch_sp[PAC1934_CH_VOLTAGE].scan_index = cnt;
1362 		ch_sp[PAC1934_CH_VOLTAGE].address = cnt + PAC1934_VBUS_1_ADDR;
1363 		ch_sp[PAC1934_CH_CURRENT].channel = cnt + 1;
1364 		ch_sp[PAC1934_CH_CURRENT].scan_index = cnt;
1365 		ch_sp[PAC1934_CH_CURRENT].address = cnt + PAC1934_VSENSE_1_ADDR;
1366 
1367 		/*
1368 		 * In order to be able to use labels for PAC1934_CH_VOLTAGE, and
1369 		 * PAC1934_CH_VOLTAGE_AVERAGE,respectively PAC1934_CH_CURRENT
1370 		 * and PAC1934_CH_CURRENT_AVERAGE we need to use different
1371 		 * channel numbers. We will add +5 (+1 to maximum PAC channels).
1372 		 */
1373 		ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].channel = cnt + 5;
1374 		ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].scan_index = cnt;
1375 		ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].address = cnt + PAC1934_VBUS_AVG_1_ADDR;
1376 		ch_sp[PAC1934_CH_CURRENT_AVERAGE].channel = cnt + 5;
1377 		ch_sp[PAC1934_CH_CURRENT_AVERAGE].scan_index = cnt;
1378 		ch_sp[PAC1934_CH_CURRENT_AVERAGE].address = cnt + PAC1934_VSENSE_AVG_1_ADDR;
1379 
1380 		/*
1381 		 * now modify the parameters in all channels if the
1382 		 * whole chip rail(channel) is bi-directional
1383 		 */
1384 		if (info->bi_dir[cnt]) {
1385 			ch_sp[PAC1934_CH_ENERGY].scan_type.sign = 's';
1386 			ch_sp[PAC1934_CH_ENERGY].scan_type.realbits = 47;
1387 			ch_sp[PAC1934_CH_POWER].scan_type.sign = 's';
1388 			ch_sp[PAC1934_CH_POWER].scan_type.realbits = 27;
1389 			ch_sp[PAC1934_CH_VOLTAGE].scan_type.sign = 's';
1390 			ch_sp[PAC1934_CH_VOLTAGE].scan_type.realbits = 15;
1391 			ch_sp[PAC1934_CH_CURRENT].scan_type.sign = 's';
1392 			ch_sp[PAC1934_CH_CURRENT].scan_type.realbits = 15;
1393 			ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].scan_type.sign = 's';
1394 			ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].scan_type.realbits = 15;
1395 			ch_sp[PAC1934_CH_CURRENT_AVERAGE].scan_type.sign = 's';
1396 			ch_sp[PAC1934_CH_CURRENT_AVERAGE].scan_type.realbits = 15;
1397 		}
1398 		tmp_data += sizeof(pac1934_single_channel);
1399 	}
1400 
1401 	/*
1402 	 * send the updated dynamic channel structure information towards IIO
1403 	 * prepare the required field for IIO class registration
1404 	 */
1405 	indio_dev->num_channels = attribute_count;
1406 	indio_dev->channels = (const struct iio_chan_spec *)dyn_ch_struct;
1407 
1408 	return 0;
1409 }
1410 
1411 static IIO_DEVICE_ATTR(in_shunt_resistor1, 0644,
1412 		       pac1934_shunt_value_show, pac1934_shunt_value_store, 0);
1413 static IIO_DEVICE_ATTR(in_shunt_resistor2, 0644,
1414 		       pac1934_shunt_value_show, pac1934_shunt_value_store, 1);
1415 static IIO_DEVICE_ATTR(in_shunt_resistor3, 0644,
1416 		       pac1934_shunt_value_show, pac1934_shunt_value_store, 2);
1417 static IIO_DEVICE_ATTR(in_shunt_resistor4, 0644,
1418 		       pac1934_shunt_value_show, pac1934_shunt_value_store, 3);
1419 
1420 static int pac1934_prep_custom_attributes(struct pac1934_chip_info *info,
1421 					  struct iio_dev *indio_dev)
1422 {
1423 	int i, active_channels_count = 0;
1424 	struct attribute **pac1934_custom_attr;
1425 	struct attribute_group *pac1934_group;
1426 	struct device *dev = &info->client->dev;
1427 
1428 	for (i = 0 ; i < info->phys_channels; i++)
1429 		if (info->active_channels[i])
1430 			active_channels_count++;
1431 
1432 	pac1934_group = devm_kzalloc(dev, sizeof(*pac1934_group), GFP_KERNEL);
1433 	if (!pac1934_group)
1434 		return -ENOMEM;
1435 
1436 	pac1934_custom_attr = devm_kzalloc(dev,
1437 					   (PAC1934_CUSTOM_ATTR_FOR_CHANNEL *
1438 					   active_channels_count)
1439 					   * sizeof(*pac1934_group) + 1,
1440 					   GFP_KERNEL);
1441 	if (!pac1934_custom_attr)
1442 		return -ENOMEM;
1443 
1444 	i = 0;
1445 	if (info->active_channels[0])
1446 		pac1934_custom_attr[i++] = PAC1934_DEV_ATTR(in_shunt_resistor1);
1447 
1448 	if (info->active_channels[1])
1449 		pac1934_custom_attr[i++] = PAC1934_DEV_ATTR(in_shunt_resistor2);
1450 
1451 	if (info->active_channels[2])
1452 		pac1934_custom_attr[i++] = PAC1934_DEV_ATTR(in_shunt_resistor3);
1453 
1454 	if (info->active_channels[3])
1455 		pac1934_custom_attr[i] = PAC1934_DEV_ATTR(in_shunt_resistor4);
1456 
1457 	pac1934_group->attrs = pac1934_custom_attr;
1458 	info->iio_info.attrs = pac1934_group;
1459 
1460 	return 0;
1461 }
1462 
1463 static void pac1934_mutex_destroy(void *data)
1464 {
1465 	struct mutex *lock = data;
1466 
1467 	mutex_destroy(lock);
1468 }
1469 
1470 static const struct iio_info pac1934_info = {
1471 	.read_raw = pac1934_read_raw,
1472 	.write_raw = pac1934_write_raw,
1473 	.read_avail = pac1934_read_avail,
1474 	.read_label = pac1934_read_label,
1475 };
1476 
1477 static int pac1934_probe(struct i2c_client *client)
1478 {
1479 	struct pac1934_chip_info *info;
1480 	const struct pac1934_features *chip;
1481 	struct iio_dev *indio_dev;
1482 	int cnt, ret;
1483 	struct device *dev = &client->dev;
1484 
1485 	indio_dev = devm_iio_device_alloc(dev, sizeof(*info));
1486 	if (!indio_dev)
1487 		return -ENOMEM;
1488 
1489 	info = iio_priv(indio_dev);
1490 
1491 	info->client = client;
1492 
1493 	/* always start with energy accumulation enabled */
1494 	for (cnt = 0; cnt < PAC1934_MAX_NUM_CHANNELS; cnt++)
1495 		info->enable_energy[cnt] = true;
1496 
1497 	ret = pac1934_chip_identify(info);
1498 	if (ret < 0) {
1499 		/*
1500 		 * If failed to identify the hardware based on internal
1501 		 * registers, try using fallback compatible in device tree
1502 		 * to deal with some newer part number.
1503 		 */
1504 		chip = i2c_get_match_data(client);
1505 		if (!chip)
1506 			return -EINVAL;
1507 
1508 		info->phys_channels = chip->phys_channels;
1509 		indio_dev->name = chip->name;
1510 	} else {
1511 		info->phys_channels = pac1934_chip_config[ret].phys_channels;
1512 		indio_dev->name = pac1934_chip_config[ret].name;
1513 	}
1514 
1515 	if (acpi_match_device(dev->driver->acpi_match_table, dev))
1516 		ret = pac1934_acpi_parse_channel_config(client, info);
1517 	else
1518 		/*
1519 		 * This makes it possible to use also ACPI PRP0001 for
1520 		 * registering the device using device tree properties.
1521 		 */
1522 		ret = pac1934_fw_parse_channel_config(client, info);
1523 
1524 	if (ret)
1525 		return dev_err_probe(dev, ret,
1526 				     "parameter parsing returned an error\n");
1527 
1528 	mutex_init(&info->lock);
1529 	ret = devm_add_action_or_reset(dev, pac1934_mutex_destroy,
1530 				       &info->lock);
1531 	if (ret < 0)
1532 		return ret;
1533 
1534 	/*
1535 	 * do now any chip specific initialization (e.g. read/write
1536 	 * some registers), enable/disable certain channels, change the sampling
1537 	 * rate to the requested value
1538 	 */
1539 	ret = pac1934_chip_configure(info);
1540 	if (ret < 0)
1541 		return ret;
1542 
1543 	/* prepare the channel information */
1544 	ret = pac1934_prep_iio_channels(info, indio_dev);
1545 	if (ret < 0)
1546 		return ret;
1547 
1548 	info->iio_info = pac1934_info;
1549 	indio_dev->info = &info->iio_info;
1550 	indio_dev->modes = INDIO_DIRECT_MODE;
1551 
1552 	ret = pac1934_prep_custom_attributes(info, indio_dev);
1553 	if (ret < 0)
1554 		return dev_err_probe(dev, ret,
1555 				     "Can't configure custom attributes for PAC1934 device\n");
1556 
1557 	/*
1558 	 * read whatever has been accumulated in the chip so far
1559 	 * and reset the accumulators
1560 	 */
1561 	ret = pac1934_reg_snapshot(info, true, PAC1934_REFRESH_REG_ADDR,
1562 				   PAC1934_MIN_UPDATE_WAIT_TIME_US);
1563 	if (ret < 0)
1564 		return ret;
1565 
1566 	ret = devm_iio_device_register(dev, indio_dev);
1567 	if (ret < 0)
1568 		return dev_err_probe(dev, ret,
1569 				     "Can't register IIO device\n");
1570 
1571 	return 0;
1572 }
1573 
1574 static const struct i2c_device_id pac1934_id[] = {
1575 	{ .name = "pac1931", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1931] },
1576 	{ .name = "pac1932", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1932] },
1577 	{ .name = "pac1933", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1933] },
1578 	{ .name = "pac1934", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1934] },
1579 	{}
1580 };
1581 MODULE_DEVICE_TABLE(i2c, pac1934_id);
1582 
1583 static const struct of_device_id pac1934_of_match[] = {
1584 	{
1585 		.compatible = "microchip,pac1931",
1586 		.data = &pac1934_chip_config[PAC1931]
1587 	},
1588 	{
1589 		.compatible = "microchip,pac1932",
1590 		.data = &pac1934_chip_config[PAC1932]
1591 	},
1592 	{
1593 		.compatible = "microchip,pac1933",
1594 		.data = &pac1934_chip_config[PAC1933]
1595 	},
1596 	{
1597 		.compatible = "microchip,pac1934",
1598 		.data = &pac1934_chip_config[PAC1934]
1599 	},
1600 	{}
1601 };
1602 MODULE_DEVICE_TABLE(of, pac1934_of_match);
1603 
1604 /*
1605  * using MCHP1930 to be compatible with BIOS ACPI. See example:
1606  * https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ApplicationNotes/ApplicationNotes/PAC1934-Integration-Notes-for-Microsoft-Windows-10-and-Windows-11-Driver-Support-DS00002534.pdf
1607  */
1608 static const struct acpi_device_id pac1934_acpi_match[] = {
1609 	{ "MCHP1930", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1934] },
1610 	{}
1611 };
1612 MODULE_DEVICE_TABLE(acpi, pac1934_acpi_match);
1613 
1614 static struct i2c_driver pac1934_driver = {
1615 	.driver	 = {
1616 		.name = "pac1934",
1617 		.of_match_table = pac1934_of_match,
1618 		.acpi_match_table = pac1934_acpi_match
1619 	},
1620 	.probe = pac1934_probe,
1621 	.id_table = pac1934_id,
1622 };
1623 
1624 module_i2c_driver(pac1934_driver);
1625 
1626 MODULE_AUTHOR("Bogdan Bolocan <bogdan.bolocan@microchip.com>");
1627 MODULE_AUTHOR("Victor Tudose");
1628 MODULE_AUTHOR("Marius Cristea <marius.cristea@microchip.com>");
1629 MODULE_DESCRIPTION("IIO driver for PAC1934 Multi-Channel DC Power/Energy Monitor");
1630 MODULE_LICENSE("GPL");
1631