1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Driver for Texas Instruments TMP512, TMP513 power monitor chips
4 *
5 * TMP513:
6 * Thermal/Power Management with Triple Remote and
7 * Local Temperature Sensor and Current Shunt Monitor
8 * Datasheet: https://www.ti.com/lit/gpn/tmp513
9 *
10 * TMP512:
11 * Thermal/Power Management with Dual Remote
12 *	and Local Temperature Sensor and Current Shunt Monitor
13 * Datasheet: https://www.ti.com/lit/gpn/tmp512
14 *
15 * Copyright (C) 2019 Eric Tremblay <etremblay@distech-controls.com>
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; version 2 of the License.
20 */
21
22#include <linux/bitops.h>
23#include <linux/bug.h>
24#include <linux/device.h>
25#include <linux/err.h>
26#include <linux/hwmon.h>
27#include <linux/i2c.h>
28#include <linux/init.h>
29#include <linux/math.h>
30#include <linux/module.h>
31#include <linux/property.h>
32#include <linux/regmap.h>
33#include <linux/slab.h>
34#include <linux/types.h>
35#include <linux/units.h>
36
37// Common register definition
38#define TMP51X_SHUNT_CONFIG		0x00
39#define TMP51X_TEMP_CONFIG		0x01
40#define TMP51X_STATUS			0x02
41#define TMP51X_SMBUS_ALERT		0x03
42#define TMP51X_SHUNT_CURRENT_RESULT	0x04
43#define TMP51X_BUS_VOLTAGE_RESULT	0x05
44#define TMP51X_POWER_RESULT		0x06
45#define TMP51X_BUS_CURRENT_RESULT	0x07
46#define TMP51X_LOCAL_TEMP_RESULT	0x08
47#define TMP51X_REMOTE_TEMP_RESULT_1	0x09
48#define TMP51X_REMOTE_TEMP_RESULT_2	0x0A
49#define TMP51X_SHUNT_CURRENT_H_LIMIT	0x0C
50#define TMP51X_SHUNT_CURRENT_L_LIMIT	0x0D
51#define TMP51X_BUS_VOLTAGE_H_LIMIT	0x0E
52#define TMP51X_BUS_VOLTAGE_L_LIMIT	0x0F
53#define TMP51X_POWER_LIMIT		0x10
54#define TMP51X_LOCAL_TEMP_LIMIT	0x11
55#define TMP51X_REMOTE_TEMP_LIMIT_1	0x12
56#define TMP51X_REMOTE_TEMP_LIMIT_2	0x13
57#define TMP51X_SHUNT_CALIBRATION	0x15
58#define TMP51X_N_FACTOR_AND_HYST_1	0x16
59#define TMP51X_N_FACTOR_2		0x17
60#define TMP51X_MAN_ID_REG		0xFE
61#define TMP51X_DEVICE_ID_REG		0xFF
62
63// TMP513 specific register definition
64#define TMP513_REMOTE_TEMP_RESULT_3	0x0B
65#define TMP513_REMOTE_TEMP_LIMIT_3	0x14
66#define TMP513_N_FACTOR_3		0x18
67
68// Common attrs, and NULL
69#define TMP51X_MANUFACTURER_ID		0x55FF
70
71#define TMP512_DEVICE_ID		0x22FF
72#define TMP513_DEVICE_ID		0x23FF
73
74// Default config
75#define TMP51X_SHUNT_CONFIG_DEFAULT	0x399F
76#define TMP51X_SHUNT_VALUE_DEFAULT	1000
77#define TMP51X_VBUS_RANGE_DEFAULT	TMP51X_VBUS_RANGE_32V
78#define TMP51X_PGA_DEFAULT		8
79#define TMP51X_MAX_REGISTER_ADDR	0xFF
80
81// Mask and shift
82#define CURRENT_SENSE_VOLTAGE_320_MASK	0x1800
83#define CURRENT_SENSE_VOLTAGE_160_MASK	0x1000
84#define CURRENT_SENSE_VOLTAGE_80_MASK	0x0800
85#define CURRENT_SENSE_VOLTAGE_40_MASK	0
86
87#define TMP51X_BUS_VOLTAGE_MASK		0x2000
88#define TMP51X_NFACTOR_MASK		0xFF00
89#define TMP51X_HYST_MASK		0x00FF
90
91#define TMP51X_BUS_VOLTAGE_SHIFT	3
92#define TMP51X_TEMP_SHIFT		3
93
94// Alarms
95#define TMP51X_SHUNT_CURRENT_H_LIMIT_POS	15
96#define TMP51X_SHUNT_CURRENT_L_LIMIT_POS	14
97#define TMP51X_BUS_VOLTAGE_H_LIMIT_POS		13
98#define TMP51X_BUS_VOLTAGE_L_LIMIT_POS		12
99#define TMP51X_POWER_LIMIT_POS			11
100#define TMP51X_LOCAL_TEMP_LIMIT_POS		10
101#define TMP51X_REMOTE_TEMP_LIMIT_1_POS		9
102#define TMP51X_REMOTE_TEMP_LIMIT_2_POS		8
103#define TMP513_REMOTE_TEMP_LIMIT_3_POS		7
104
105#define TMP51X_VBUS_RANGE_32V		(32 * MICRO)
106#define TMP51X_VBUS_RANGE_16V		(16 * MICRO)
107
108// Max and Min value
109#define MAX_BUS_VOLTAGE_32_LIMIT	32764
110#define MAX_BUS_VOLTAGE_16_LIMIT	16382
111
112// Max possible value is -256 to +256 but datasheet indicated -40 to 125.
113#define MAX_TEMP_LIMIT			125000
114#define MIN_TEMP_LIMIT			-40000
115
116#define MAX_TEMP_HYST			127500
117
118#define TMP512_MAX_CHANNELS		3
119#define TMP513_MAX_CHANNELS		4
120
121#define TMP51X_TEMP_CONFIG_CONV_RATE	GENMASK(9, 7)
122#define TMP51X_TEMP_CONFIG_RC		BIT(10)
123#define TMP51X_TEMP_CHANNEL_MASK(n)	(GENMASK((n) - 1, 0) << 11)
124#define TMP51X_TEMP_CONFIG_CONT		BIT(15)
125#define TMP51X_TEMP_CONFIG_DEFAULT(n)					\
126	(TMP51X_TEMP_CHANNEL_MASK(n) | TMP51X_TEMP_CONFIG_CONT |	\
127	 TMP51X_TEMP_CONFIG_CONV_RATE | TMP51X_TEMP_CONFIG_RC)
128
129static const u8 TMP51X_TEMP_INPUT[4] = {
130	TMP51X_LOCAL_TEMP_RESULT,
131	TMP51X_REMOTE_TEMP_RESULT_1,
132	TMP51X_REMOTE_TEMP_RESULT_2,
133	TMP513_REMOTE_TEMP_RESULT_3
134};
135
136static const u8 TMP51X_TEMP_CRIT[4] = {
137	TMP51X_LOCAL_TEMP_LIMIT,
138	TMP51X_REMOTE_TEMP_LIMIT_1,
139	TMP51X_REMOTE_TEMP_LIMIT_2,
140	TMP513_REMOTE_TEMP_LIMIT_3
141};
142
143static const u8 TMP51X_TEMP_CRIT_ALARM[4] = {
144	TMP51X_LOCAL_TEMP_LIMIT_POS,
145	TMP51X_REMOTE_TEMP_LIMIT_1_POS,
146	TMP51X_REMOTE_TEMP_LIMIT_2_POS,
147	TMP513_REMOTE_TEMP_LIMIT_3_POS
148};
149
150static const u8 TMP51X_TEMP_CRIT_HYST[4] = {
151	TMP51X_N_FACTOR_AND_HYST_1,
152	TMP51X_N_FACTOR_AND_HYST_1,
153	TMP51X_N_FACTOR_AND_HYST_1,
154	TMP51X_N_FACTOR_AND_HYST_1
155};
156
157static const u8 TMP51X_CURR_INPUT[2] = {
158	TMP51X_SHUNT_CURRENT_RESULT,
159	TMP51X_BUS_CURRENT_RESULT
160};
161
162static struct regmap_config tmp51x_regmap_config = {
163	.reg_bits = 8,
164	.val_bits = 16,
165	.max_register = TMP51X_MAX_REGISTER_ADDR,
166};
167
168struct tmp51x_data {
169	u16 shunt_config;
170	u16 pga_gain;
171	u32 vbus_range_uvolt;
172
173	u16 temp_config;
174	u32 nfactor[3];
175
176	u32 shunt_uohms;
177
178	u32 curr_lsb_ua;
179	u32 pwr_lsb_uw;
180
181	u8 max_channels;
182	struct regmap *regmap;
183};
184
185// Set the shift based on the gain 8=4, 4=3, 2=2, 1=1
186static inline u8 tmp51x_get_pga_shift(struct tmp51x_data *data)
187{
188	return 5 - ffs(data->pga_gain);
189}
190
191static int tmp51x_get_value(struct tmp51x_data *data, u8 reg, u8 pos,
192			    unsigned int regval, long *val)
193{
194	switch (reg) {
195	case TMP51X_STATUS:
196		*val = (regval >> pos) & 1;
197		break;
198	case TMP51X_SHUNT_CURRENT_RESULT:
199	case TMP51X_SHUNT_CURRENT_H_LIMIT:
200	case TMP51X_SHUNT_CURRENT_L_LIMIT:
201		/*
202		 * The valus is read in voltage in the chip but reported as
203		 * current to the user.
204		 * 2's complement number shifted by one to four depending
205		 * on the pga gain setting. 1lsb = 10uV
206		 */
207		*val = sign_extend32(regval, 17 - tmp51x_get_pga_shift(data));
208		*val = DIV_ROUND_CLOSEST(*val * 10 * MILLI, data->shunt_uohms);
209		break;
210	case TMP51X_BUS_VOLTAGE_RESULT:
211	case TMP51X_BUS_VOLTAGE_H_LIMIT:
212	case TMP51X_BUS_VOLTAGE_L_LIMIT:
213		// 1lsb = 4mV
214		*val = (regval >> TMP51X_BUS_VOLTAGE_SHIFT) * 4;
215		break;
216	case TMP51X_POWER_RESULT:
217	case TMP51X_POWER_LIMIT:
218		// Power = (current * BusVoltage) / 5000
219		*val = regval * data->pwr_lsb_uw;
220		break;
221	case TMP51X_BUS_CURRENT_RESULT:
222		// Current = (ShuntVoltage * CalibrationRegister) / 4096
223		*val = sign_extend32(regval, 16) * data->curr_lsb_ua;
224		*val = DIV_ROUND_CLOSEST(*val, MILLI);
225		break;
226	case TMP51X_LOCAL_TEMP_RESULT:
227	case TMP51X_REMOTE_TEMP_RESULT_1:
228	case TMP51X_REMOTE_TEMP_RESULT_2:
229	case TMP513_REMOTE_TEMP_RESULT_3:
230	case TMP51X_LOCAL_TEMP_LIMIT:
231	case TMP51X_REMOTE_TEMP_LIMIT_1:
232	case TMP51X_REMOTE_TEMP_LIMIT_2:
233	case TMP513_REMOTE_TEMP_LIMIT_3:
234		// 1lsb = 0.0625 degrees centigrade
235		*val = sign_extend32(regval, 16) >> TMP51X_TEMP_SHIFT;
236		*val = DIV_ROUND_CLOSEST(*val * 625, 10);
237		break;
238	case TMP51X_N_FACTOR_AND_HYST_1:
239		// 1lsb = 0.5 degrees centigrade
240		*val = (regval & TMP51X_HYST_MASK) * 500;
241		break;
242	default:
243		// Programmer goofed
244		WARN_ON_ONCE(1);
245		*val = 0;
246		return -EOPNOTSUPP;
247	}
248
249	return 0;
250}
251
252static int tmp51x_set_value(struct tmp51x_data *data, u8 reg, long val)
253{
254	int regval, max_val;
255	u32 mask = 0;
256
257	switch (reg) {
258	case TMP51X_SHUNT_CURRENT_H_LIMIT:
259	case TMP51X_SHUNT_CURRENT_L_LIMIT:
260		/*
261		 * The user enter current value and we convert it to
262		 * voltage. 1lsb = 10uV
263		 */
264		val = DIV_ROUND_CLOSEST(val * data->shunt_uohms, 10 * MILLI);
265		max_val = U16_MAX >> tmp51x_get_pga_shift(data);
266		regval = clamp_val(val, -max_val, max_val);
267		break;
268	case TMP51X_BUS_VOLTAGE_H_LIMIT:
269	case TMP51X_BUS_VOLTAGE_L_LIMIT:
270		// 1lsb = 4mV
271		max_val = (data->vbus_range_uvolt == TMP51X_VBUS_RANGE_32V) ?
272			MAX_BUS_VOLTAGE_32_LIMIT : MAX_BUS_VOLTAGE_16_LIMIT;
273
274		val = clamp_val(DIV_ROUND_CLOSEST(val, 4), 0, max_val);
275		regval = val << TMP51X_BUS_VOLTAGE_SHIFT;
276		break;
277	case TMP51X_POWER_LIMIT:
278		regval = clamp_val(DIV_ROUND_CLOSEST(val, data->pwr_lsb_uw), 0,
279				   U16_MAX);
280		break;
281	case TMP51X_LOCAL_TEMP_LIMIT:
282	case TMP51X_REMOTE_TEMP_LIMIT_1:
283	case TMP51X_REMOTE_TEMP_LIMIT_2:
284	case TMP513_REMOTE_TEMP_LIMIT_3:
285		// 1lsb = 0.0625 degrees centigrade
286		val = clamp_val(val, MIN_TEMP_LIMIT, MAX_TEMP_LIMIT);
287		regval = DIV_ROUND_CLOSEST(val * 10, 625) << TMP51X_TEMP_SHIFT;
288		break;
289	case TMP51X_N_FACTOR_AND_HYST_1:
290		// 1lsb = 0.5 degrees centigrade
291		val = clamp_val(val, 0, MAX_TEMP_HYST);
292		regval = DIV_ROUND_CLOSEST(val, 500);
293		mask = TMP51X_HYST_MASK;
294		break;
295	default:
296		// Programmer goofed
297		WARN_ON_ONCE(1);
298		return -EOPNOTSUPP;
299	}
300
301	if (mask == 0)
302		return regmap_write(data->regmap, reg, regval);
303	else
304		return regmap_update_bits(data->regmap, reg, mask, regval);
305}
306
307static u8 tmp51x_get_reg(enum hwmon_sensor_types type, u32 attr, int channel)
308{
309	switch (type) {
310	case hwmon_temp:
311		switch (attr) {
312		case hwmon_temp_input:
313			return TMP51X_TEMP_INPUT[channel];
314		case hwmon_temp_crit_alarm:
315			return TMP51X_STATUS;
316		case hwmon_temp_crit:
317			return TMP51X_TEMP_CRIT[channel];
318		case hwmon_temp_crit_hyst:
319			return TMP51X_TEMP_CRIT_HYST[channel];
320		}
321		break;
322	case hwmon_in:
323		switch (attr) {
324		case hwmon_in_input:
325			return TMP51X_BUS_VOLTAGE_RESULT;
326		case hwmon_in_lcrit_alarm:
327		case hwmon_in_crit_alarm:
328			return TMP51X_STATUS;
329		case hwmon_in_lcrit:
330			return TMP51X_BUS_VOLTAGE_L_LIMIT;
331		case hwmon_in_crit:
332			return TMP51X_BUS_VOLTAGE_H_LIMIT;
333		}
334		break;
335	case hwmon_curr:
336		switch (attr) {
337		case hwmon_curr_input:
338			return TMP51X_CURR_INPUT[channel];
339		case hwmon_curr_lcrit_alarm:
340		case hwmon_curr_crit_alarm:
341			return TMP51X_STATUS;
342		case hwmon_curr_lcrit:
343			return TMP51X_SHUNT_CURRENT_L_LIMIT;
344		case hwmon_curr_crit:
345			return TMP51X_SHUNT_CURRENT_H_LIMIT;
346		}
347		break;
348	case hwmon_power:
349		switch (attr) {
350		case hwmon_power_input:
351			return TMP51X_POWER_RESULT;
352		case hwmon_power_crit_alarm:
353			return TMP51X_STATUS;
354		case hwmon_power_crit:
355			return TMP51X_POWER_LIMIT;
356		}
357		break;
358	default:
359		break;
360	}
361
362	return 0;
363}
364
365static u8 tmp51x_get_status_pos(enum hwmon_sensor_types type, u32 attr,
366				int channel)
367{
368	switch (type) {
369	case hwmon_temp:
370		switch (attr) {
371		case hwmon_temp_crit_alarm:
372			return TMP51X_TEMP_CRIT_ALARM[channel];
373		}
374		break;
375	case hwmon_in:
376		switch (attr) {
377		case hwmon_in_lcrit_alarm:
378			return TMP51X_BUS_VOLTAGE_L_LIMIT_POS;
379		case hwmon_in_crit_alarm:
380			return TMP51X_BUS_VOLTAGE_H_LIMIT_POS;
381		}
382		break;
383	case hwmon_curr:
384		switch (attr) {
385		case hwmon_curr_lcrit_alarm:
386			return TMP51X_SHUNT_CURRENT_L_LIMIT_POS;
387		case hwmon_curr_crit_alarm:
388			return TMP51X_SHUNT_CURRENT_H_LIMIT_POS;
389		}
390		break;
391	case hwmon_power:
392		switch (attr) {
393		case hwmon_power_crit_alarm:
394			return TMP51X_POWER_LIMIT_POS;
395		}
396		break;
397	default:
398		break;
399	}
400
401	return 0;
402}
403
404static int tmp51x_read(struct device *dev, enum hwmon_sensor_types type,
405		       u32 attr, int channel, long *val)
406{
407	struct tmp51x_data *data = dev_get_drvdata(dev);
408	int ret;
409	u32 regval;
410	u8 pos = 0, reg = 0;
411
412	reg = tmp51x_get_reg(type, attr, channel);
413	if (reg == 0)
414		return -EOPNOTSUPP;
415
416	if (reg == TMP51X_STATUS)
417		pos = tmp51x_get_status_pos(type, attr, channel);
418
419	ret = regmap_read(data->regmap, reg, &regval);
420	if (ret < 0)
421		return ret;
422
423	return tmp51x_get_value(data, reg, pos, regval, val);
424}
425
426static int tmp51x_write(struct device *dev, enum hwmon_sensor_types type,
427			u32 attr, int channel, long val)
428{
429	u8 reg = 0;
430
431	reg = tmp51x_get_reg(type, attr, channel);
432	if (reg == 0)
433		return -EOPNOTSUPP;
434
435	return tmp51x_set_value(dev_get_drvdata(dev), reg, val);
436}
437
438static umode_t tmp51x_is_visible(const void *_data,
439				 enum hwmon_sensor_types type, u32 attr,
440				 int channel)
441{
442	const struct tmp51x_data *data = _data;
443
444	switch (type) {
445	case hwmon_temp:
446		if (channel >= data->max_channels)
447			return 0;
448		switch (attr) {
449		case hwmon_temp_input:
450		case hwmon_temp_crit_alarm:
451			return 0444;
452		case hwmon_temp_crit:
453			return 0644;
454		case hwmon_temp_crit_hyst:
455			if (channel == 0)
456				return 0644;
457			return 0444;
458		}
459		break;
460	case hwmon_in:
461		switch (attr) {
462		case hwmon_in_input:
463		case hwmon_in_lcrit_alarm:
464		case hwmon_in_crit_alarm:
465			return 0444;
466		case hwmon_in_lcrit:
467		case hwmon_in_crit:
468			return 0644;
469		}
470		break;
471	case hwmon_curr:
472		if (!data->shunt_uohms)
473			return 0;
474
475		switch (attr) {
476		case hwmon_curr_input:
477		case hwmon_curr_lcrit_alarm:
478		case hwmon_curr_crit_alarm:
479			return 0444;
480		case hwmon_curr_lcrit:
481		case hwmon_curr_crit:
482			return 0644;
483		}
484		break;
485	case hwmon_power:
486		if (!data->shunt_uohms)
487			return 0;
488
489		switch (attr) {
490		case hwmon_power_input:
491		case hwmon_power_crit_alarm:
492			return 0444;
493		case hwmon_power_crit:
494			return 0644;
495		}
496		break;
497	default:
498		break;
499	}
500	return 0;
501}
502
503static const struct hwmon_channel_info * const tmp51x_info[] = {
504	HWMON_CHANNEL_INFO(temp,
505			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
506			   HWMON_T_CRIT_HYST,
507			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
508			   HWMON_T_CRIT_HYST,
509			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
510			   HWMON_T_CRIT_HYST,
511			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
512			   HWMON_T_CRIT_HYST),
513	HWMON_CHANNEL_INFO(in,
514			   HWMON_I_INPUT | HWMON_I_LCRIT | HWMON_I_LCRIT_ALARM |
515			   HWMON_I_CRIT | HWMON_I_CRIT_ALARM),
516	HWMON_CHANNEL_INFO(curr,
517			   HWMON_C_INPUT | HWMON_C_LCRIT | HWMON_C_LCRIT_ALARM |
518			   HWMON_C_CRIT | HWMON_C_CRIT_ALARM,
519			   HWMON_C_INPUT),
520	HWMON_CHANNEL_INFO(power,
521			   HWMON_P_INPUT | HWMON_P_CRIT | HWMON_P_CRIT_ALARM),
522	NULL
523};
524
525static const struct hwmon_ops tmp51x_hwmon_ops = {
526	.is_visible = tmp51x_is_visible,
527	.read = tmp51x_read,
528	.write = tmp51x_write,
529};
530
531static const struct hwmon_chip_info tmp51x_chip_info = {
532	.ops = &tmp51x_hwmon_ops,
533	.info = tmp51x_info,
534};
535
536/*
537 * Calibrate the tmp51x following the datasheet method
538 */
539static int tmp51x_calibrate(struct tmp51x_data *data)
540{
541	int vshunt_max = data->pga_gain * 40;
542	u64 max_curr_ma;
543	u32 div;
544
545	/*
546	 * If shunt_uohms is equal to 0, the calibration should be set to 0.
547	 * The consequence will be that the current and power measurement engine
548	 * of the sensor will not work. Temperature and voltage sensing will
549	 * continue to work.
550	 */
551	if (data->shunt_uohms == 0)
552		return regmap_write(data->regmap, TMP51X_SHUNT_CALIBRATION, 0);
553
554	max_curr_ma = DIV_ROUND_CLOSEST_ULL(vshunt_max * MICRO, data->shunt_uohms);
555
556	/*
557	 * Calculate the minimal bit resolution for the current and the power.
558	 * Those values will be used during register interpretation.
559	 */
560	data->curr_lsb_ua = DIV_ROUND_CLOSEST_ULL(max_curr_ma * MILLI, 32767);
561	data->pwr_lsb_uw = 20 * data->curr_lsb_ua;
562
563	div = DIV_ROUND_CLOSEST_ULL(data->curr_lsb_ua * data->shunt_uohms, MICRO);
564
565	return regmap_write(data->regmap, TMP51X_SHUNT_CALIBRATION,
566			    DIV_ROUND_CLOSEST(40960, div));
567}
568
569/*
570 * Initialize the configuration and calibration registers.
571 */
572static int tmp51x_init(struct tmp51x_data *data)
573{
574	unsigned int regval;
575	int ret = regmap_write(data->regmap, TMP51X_SHUNT_CONFIG,
576			       data->shunt_config);
577	if (ret < 0)
578		return ret;
579
580	ret = regmap_write(data->regmap, TMP51X_TEMP_CONFIG, data->temp_config);
581	if (ret < 0)
582		return ret;
583
584	// nFactor configuration
585	ret = regmap_update_bits(data->regmap, TMP51X_N_FACTOR_AND_HYST_1,
586				 TMP51X_NFACTOR_MASK, data->nfactor[0] << 8);
587	if (ret < 0)
588		return ret;
589
590	ret = regmap_write(data->regmap, TMP51X_N_FACTOR_2,
591			   data->nfactor[1] << 8);
592	if (ret < 0)
593		return ret;
594
595	if (data->max_channels == TMP513_MAX_CHANNELS) {
596		ret = regmap_write(data->regmap, TMP513_N_FACTOR_3,
597				   data->nfactor[2] << 8);
598		if (ret < 0)
599			return ret;
600	}
601
602	ret = tmp51x_calibrate(data);
603	if (ret < 0)
604		return ret;
605
606	// Read the status register before using as the datasheet propose
607	return regmap_read(data->regmap, TMP51X_STATUS, &regval);
608}
609
610static const struct i2c_device_id tmp51x_id[] = {
611	{ "tmp512", TMP512_MAX_CHANNELS },
612	{ "tmp513", TMP513_MAX_CHANNELS },
613	{ }
614};
615MODULE_DEVICE_TABLE(i2c, tmp51x_id);
616
617static const struct of_device_id tmp51x_of_match[] = {
618	{ .compatible = "ti,tmp512", .data = (void *)TMP512_MAX_CHANNELS },
619	{ .compatible = "ti,tmp513", .data = (void *)TMP513_MAX_CHANNELS },
620	{ }
621};
622MODULE_DEVICE_TABLE(of, tmp51x_of_match);
623
624static int tmp51x_vbus_range_to_reg(struct device *dev,
625				    struct tmp51x_data *data)
626{
627	if (data->vbus_range_uvolt == TMP51X_VBUS_RANGE_32V) {
628		data->shunt_config |= TMP51X_BUS_VOLTAGE_MASK;
629	} else if (data->vbus_range_uvolt == TMP51X_VBUS_RANGE_16V) {
630		data->shunt_config &= ~TMP51X_BUS_VOLTAGE_MASK;
631	} else {
632		return dev_err_probe(dev, -EINVAL,
633				     "ti,bus-range-microvolt is invalid: %u\n",
634				     data->vbus_range_uvolt);
635	}
636	return 0;
637}
638
639static int tmp51x_pga_gain_to_reg(struct device *dev, struct tmp51x_data *data)
640{
641	if (data->pga_gain == 8) {
642		data->shunt_config |= CURRENT_SENSE_VOLTAGE_320_MASK;
643	} else if (data->pga_gain == 4) {
644		data->shunt_config |= CURRENT_SENSE_VOLTAGE_160_MASK;
645	} else if (data->pga_gain == 2) {
646		data->shunt_config |= CURRENT_SENSE_VOLTAGE_80_MASK;
647	} else if (data->pga_gain == 1) {
648		data->shunt_config |= CURRENT_SENSE_VOLTAGE_40_MASK;
649	} else {
650		return dev_err_probe(dev, -EINVAL,
651				     "ti,pga-gain is invalid: %u\n", data->pga_gain);
652	}
653	return 0;
654}
655
656static int tmp51x_read_properties(struct device *dev, struct tmp51x_data *data)
657{
658	int ret;
659	u32 val;
660
661	ret = device_property_read_u32(dev, "shunt-resistor-micro-ohms", &val);
662	data->shunt_uohms = (ret >= 0) ? val : TMP51X_SHUNT_VALUE_DEFAULT;
663
664	ret = device_property_read_u32(dev, "ti,bus-range-microvolt", &val);
665	data->vbus_range_uvolt = (ret >= 0) ? val : TMP51X_VBUS_RANGE_DEFAULT;
666	ret = tmp51x_vbus_range_to_reg(dev, data);
667	if (ret < 0)
668		return ret;
669
670	ret = device_property_read_u32(dev, "ti,pga-gain", &val);
671	data->pga_gain = (ret >= 0) ? val : TMP51X_PGA_DEFAULT;
672	ret = tmp51x_pga_gain_to_reg(dev, data);
673	if (ret < 0)
674		return ret;
675
676	device_property_read_u32_array(dev, "ti,nfactor", data->nfactor,
677				       data->max_channels - 1);
678
679	// Check if shunt value is compatible with pga-gain
680	if (data->shunt_uohms > data->pga_gain * 40 * MICRO) {
681		return dev_err_probe(dev, -EINVAL,
682				     "shunt-resistor: %u too big for pga_gain: %u\n",
683				     data->shunt_uohms, data->pga_gain);
684	}
685
686	return 0;
687}
688
689static void tmp51x_use_default(struct tmp51x_data *data)
690{
691	data->vbus_range_uvolt = TMP51X_VBUS_RANGE_DEFAULT;
692	data->pga_gain = TMP51X_PGA_DEFAULT;
693	data->shunt_uohms = TMP51X_SHUNT_VALUE_DEFAULT;
694}
695
696static int tmp51x_configure(struct device *dev, struct tmp51x_data *data)
697{
698	data->shunt_config = TMP51X_SHUNT_CONFIG_DEFAULT;
699	data->temp_config = TMP51X_TEMP_CONFIG_DEFAULT(data->max_channels);
700
701	if (dev->of_node)
702		return tmp51x_read_properties(dev, data);
703
704	tmp51x_use_default(data);
705
706	return 0;
707}
708
709static int tmp51x_probe(struct i2c_client *client)
710{
711	struct device *dev = &client->dev;
712	struct tmp51x_data *data;
713	struct device *hwmon_dev;
714	int ret;
715
716	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
717	if (!data)
718		return -ENOMEM;
719
720	data->max_channels = (uintptr_t)i2c_get_match_data(client);
721
722	ret = tmp51x_configure(dev, data);
723	if (ret < 0)
724		return dev_err_probe(dev, ret, "error configuring the device\n");
725
726	data->regmap = devm_regmap_init_i2c(client, &tmp51x_regmap_config);
727	if (IS_ERR(data->regmap))
728		return dev_err_probe(dev, PTR_ERR(data->regmap),
729				     "failed to allocate register map\n");
730
731	ret = tmp51x_init(data);
732	if (ret < 0)
733		return dev_err_probe(dev, ret, "error configuring the device\n");
734
735	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
736							 data,
737							 &tmp51x_chip_info,
738							 NULL);
739	if (IS_ERR(hwmon_dev))
740		return PTR_ERR(hwmon_dev);
741
742	dev_dbg(dev, "power monitor %s\n", client->name);
743
744	return 0;
745}
746
747static struct i2c_driver tmp51x_driver = {
748	.driver = {
749		.name	= "tmp51x",
750		.of_match_table = tmp51x_of_match,
751	},
752	.probe		= tmp51x_probe,
753	.id_table	= tmp51x_id,
754};
755
756module_i2c_driver(tmp51x_driver);
757
758MODULE_AUTHOR("Eric Tremblay <etremblay@distechcontrols.com>");
759MODULE_DESCRIPTION("tmp51x driver");
760MODULE_LICENSE("GPL");
761