xref: /linux/drivers/hwmon/tmp513.c (revision d74276290cf92bc16d129fc38883ab448128048c)
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 
129 static 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 
136 static 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 
143 static 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 
150 static 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 
157 static const u8 TMP51X_CURR_INPUT[2] = {
158 	TMP51X_SHUNT_CURRENT_RESULT,
159 	TMP51X_BUS_CURRENT_RESULT
160 };
161 
162 static const struct regmap_config tmp51x_regmap_config = {
163 	.reg_bits = 8,
164 	.val_bits = 16,
165 	.max_register = TMP51X_MAX_REGISTER_ADDR,
166 };
167 
168 struct 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 -> 1, 4 -> 2, 2 -> 3, 1 -> 4
tmp51x_get_pga_shift(struct tmp51x_data * data)186 static inline u8 tmp51x_get_pga_shift(struct tmp51x_data *data)
187 {
188 	return 5 - ffs(data->pga_gain);
189 }
190 
tmp51x_get_value(struct tmp51x_data * data,u8 reg,u8 pos,unsigned int regval,long * val)191 static 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,
208 				     reg == TMP51X_SHUNT_CURRENT_RESULT ?
209 				     16 - tmp51x_get_pga_shift(data) : 15);
210 		*val = DIV_ROUND_CLOSEST(*val * 10 * MILLI, data->shunt_uohms);
211 		break;
212 	case TMP51X_BUS_VOLTAGE_RESULT:
213 	case TMP51X_BUS_VOLTAGE_H_LIMIT:
214 	case TMP51X_BUS_VOLTAGE_L_LIMIT:
215 		// 1lsb = 4mV
216 		*val = (regval >> TMP51X_BUS_VOLTAGE_SHIFT) * 4;
217 		break;
218 	case TMP51X_POWER_RESULT:
219 	case TMP51X_POWER_LIMIT:
220 		// Power = (current * BusVoltage) / 5000
221 		*val = regval * data->pwr_lsb_uw;
222 		break;
223 	case TMP51X_BUS_CURRENT_RESULT:
224 		// Current = (ShuntVoltage * CalibrationRegister) / 4096
225 		*val = sign_extend32(regval, 15) * (long)data->curr_lsb_ua;
226 		*val = DIV_ROUND_CLOSEST(*val, MILLI);
227 		break;
228 	case TMP51X_LOCAL_TEMP_RESULT:
229 	case TMP51X_REMOTE_TEMP_RESULT_1:
230 	case TMP51X_REMOTE_TEMP_RESULT_2:
231 	case TMP513_REMOTE_TEMP_RESULT_3:
232 	case TMP51X_LOCAL_TEMP_LIMIT:
233 	case TMP51X_REMOTE_TEMP_LIMIT_1:
234 	case TMP51X_REMOTE_TEMP_LIMIT_2:
235 	case TMP513_REMOTE_TEMP_LIMIT_3:
236 		// 1lsb = 0.0625 degrees centigrade
237 		*val = sign_extend32(regval, 15) >> TMP51X_TEMP_SHIFT;
238 		*val = DIV_ROUND_CLOSEST(*val * 625, 10);
239 		break;
240 	case TMP51X_N_FACTOR_AND_HYST_1:
241 		// 1lsb = 0.5 degrees centigrade
242 		*val = (regval & TMP51X_HYST_MASK) * 500;
243 		break;
244 	default:
245 		// Programmer goofed
246 		WARN_ON_ONCE(1);
247 		*val = 0;
248 		return -EOPNOTSUPP;
249 	}
250 
251 	return 0;
252 }
253 
tmp51x_set_value(struct tmp51x_data * data,u8 reg,long val)254 static int tmp51x_set_value(struct tmp51x_data *data, u8 reg, long val)
255 {
256 	int regval, max_val;
257 	u32 mask = 0;
258 
259 	switch (reg) {
260 	case TMP51X_SHUNT_CURRENT_H_LIMIT:
261 	case TMP51X_SHUNT_CURRENT_L_LIMIT:
262 		/*
263 		 * The user enter current value and we convert it to
264 		 * voltage. 1lsb = 10uV
265 		 */
266 		val = DIV_ROUND_CLOSEST(val * data->shunt_uohms, 10 * MILLI);
267 		max_val = U16_MAX >> tmp51x_get_pga_shift(data);
268 		regval = clamp_val(val, -max_val, max_val);
269 		break;
270 	case TMP51X_BUS_VOLTAGE_H_LIMIT:
271 	case TMP51X_BUS_VOLTAGE_L_LIMIT:
272 		// 1lsb = 4mV
273 		max_val = (data->vbus_range_uvolt == TMP51X_VBUS_RANGE_32V) ?
274 			MAX_BUS_VOLTAGE_32_LIMIT : MAX_BUS_VOLTAGE_16_LIMIT;
275 
276 		val = clamp_val(DIV_ROUND_CLOSEST(val, 4), 0, max_val);
277 		regval = val << TMP51X_BUS_VOLTAGE_SHIFT;
278 		break;
279 	case TMP51X_POWER_LIMIT:
280 		regval = clamp_val(DIV_ROUND_CLOSEST(val, data->pwr_lsb_uw), 0,
281 				   U16_MAX);
282 		break;
283 	case TMP51X_LOCAL_TEMP_LIMIT:
284 	case TMP51X_REMOTE_TEMP_LIMIT_1:
285 	case TMP51X_REMOTE_TEMP_LIMIT_2:
286 	case TMP513_REMOTE_TEMP_LIMIT_3:
287 		// 1lsb = 0.0625 degrees centigrade
288 		val = clamp_val(val, MIN_TEMP_LIMIT, MAX_TEMP_LIMIT);
289 		regval = DIV_ROUND_CLOSEST(val * 10, 625) << TMP51X_TEMP_SHIFT;
290 		break;
291 	case TMP51X_N_FACTOR_AND_HYST_1:
292 		// 1lsb = 0.5 degrees centigrade
293 		val = clamp_val(val, 0, MAX_TEMP_HYST);
294 		regval = DIV_ROUND_CLOSEST(val, 500);
295 		mask = TMP51X_HYST_MASK;
296 		break;
297 	default:
298 		// Programmer goofed
299 		WARN_ON_ONCE(1);
300 		return -EOPNOTSUPP;
301 	}
302 
303 	if (mask == 0)
304 		return regmap_write(data->regmap, reg, regval);
305 	else
306 		return regmap_update_bits(data->regmap, reg, mask, regval);
307 }
308 
tmp51x_get_reg(enum hwmon_sensor_types type,u32 attr,int channel)309 static u8 tmp51x_get_reg(enum hwmon_sensor_types type, u32 attr, int channel)
310 {
311 	switch (type) {
312 	case hwmon_temp:
313 		switch (attr) {
314 		case hwmon_temp_input:
315 			return TMP51X_TEMP_INPUT[channel];
316 		case hwmon_temp_crit_alarm:
317 			return TMP51X_STATUS;
318 		case hwmon_temp_crit:
319 			return TMP51X_TEMP_CRIT[channel];
320 		case hwmon_temp_crit_hyst:
321 			return TMP51X_TEMP_CRIT_HYST[channel];
322 		}
323 		break;
324 	case hwmon_in:
325 		switch (attr) {
326 		case hwmon_in_input:
327 			return TMP51X_BUS_VOLTAGE_RESULT;
328 		case hwmon_in_lcrit_alarm:
329 		case hwmon_in_crit_alarm:
330 			return TMP51X_STATUS;
331 		case hwmon_in_lcrit:
332 			return TMP51X_BUS_VOLTAGE_L_LIMIT;
333 		case hwmon_in_crit:
334 			return TMP51X_BUS_VOLTAGE_H_LIMIT;
335 		}
336 		break;
337 	case hwmon_curr:
338 		switch (attr) {
339 		case hwmon_curr_input:
340 			return TMP51X_CURR_INPUT[channel];
341 		case hwmon_curr_lcrit_alarm:
342 		case hwmon_curr_crit_alarm:
343 			return TMP51X_STATUS;
344 		case hwmon_curr_lcrit:
345 			return TMP51X_SHUNT_CURRENT_L_LIMIT;
346 		case hwmon_curr_crit:
347 			return TMP51X_SHUNT_CURRENT_H_LIMIT;
348 		}
349 		break;
350 	case hwmon_power:
351 		switch (attr) {
352 		case hwmon_power_input:
353 			return TMP51X_POWER_RESULT;
354 		case hwmon_power_crit_alarm:
355 			return TMP51X_STATUS;
356 		case hwmon_power_crit:
357 			return TMP51X_POWER_LIMIT;
358 		}
359 		break;
360 	default:
361 		break;
362 	}
363 
364 	return 0;
365 }
366 
tmp51x_get_status_pos(enum hwmon_sensor_types type,u32 attr,int channel)367 static u8 tmp51x_get_status_pos(enum hwmon_sensor_types type, u32 attr,
368 				int channel)
369 {
370 	switch (type) {
371 	case hwmon_temp:
372 		switch (attr) {
373 		case hwmon_temp_crit_alarm:
374 			return TMP51X_TEMP_CRIT_ALARM[channel];
375 		}
376 		break;
377 	case hwmon_in:
378 		switch (attr) {
379 		case hwmon_in_lcrit_alarm:
380 			return TMP51X_BUS_VOLTAGE_L_LIMIT_POS;
381 		case hwmon_in_crit_alarm:
382 			return TMP51X_BUS_VOLTAGE_H_LIMIT_POS;
383 		}
384 		break;
385 	case hwmon_curr:
386 		switch (attr) {
387 		case hwmon_curr_lcrit_alarm:
388 			return TMP51X_SHUNT_CURRENT_L_LIMIT_POS;
389 		case hwmon_curr_crit_alarm:
390 			return TMP51X_SHUNT_CURRENT_H_LIMIT_POS;
391 		}
392 		break;
393 	case hwmon_power:
394 		switch (attr) {
395 		case hwmon_power_crit_alarm:
396 			return TMP51X_POWER_LIMIT_POS;
397 		}
398 		break;
399 	default:
400 		break;
401 	}
402 
403 	return 0;
404 }
405 
tmp51x_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)406 static int tmp51x_read(struct device *dev, enum hwmon_sensor_types type,
407 		       u32 attr, int channel, long *val)
408 {
409 	struct tmp51x_data *data = dev_get_drvdata(dev);
410 	int ret;
411 	u32 regval;
412 	u8 pos = 0, reg = 0;
413 
414 	reg = tmp51x_get_reg(type, attr, channel);
415 	if (reg == 0)
416 		return -EOPNOTSUPP;
417 
418 	if (reg == TMP51X_STATUS)
419 		pos = tmp51x_get_status_pos(type, attr, channel);
420 
421 	ret = regmap_read(data->regmap, reg, &regval);
422 	if (ret < 0)
423 		return ret;
424 
425 	return tmp51x_get_value(data, reg, pos, regval, val);
426 }
427 
tmp51x_write(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long val)428 static int tmp51x_write(struct device *dev, enum hwmon_sensor_types type,
429 			u32 attr, int channel, long val)
430 {
431 	u8 reg = 0;
432 
433 	reg = tmp51x_get_reg(type, attr, channel);
434 	if (reg == 0)
435 		return -EOPNOTSUPP;
436 
437 	return tmp51x_set_value(dev_get_drvdata(dev), reg, val);
438 }
439 
tmp51x_is_visible(const void * _data,enum hwmon_sensor_types type,u32 attr,int channel)440 static umode_t tmp51x_is_visible(const void *_data,
441 				 enum hwmon_sensor_types type, u32 attr,
442 				 int channel)
443 {
444 	const struct tmp51x_data *data = _data;
445 
446 	switch (type) {
447 	case hwmon_temp:
448 		if (channel >= data->max_channels)
449 			return 0;
450 		switch (attr) {
451 		case hwmon_temp_input:
452 		case hwmon_temp_crit_alarm:
453 			return 0444;
454 		case hwmon_temp_crit:
455 			return 0644;
456 		case hwmon_temp_crit_hyst:
457 			if (channel == 0)
458 				return 0644;
459 			return 0444;
460 		}
461 		break;
462 	case hwmon_in:
463 		switch (attr) {
464 		case hwmon_in_input:
465 		case hwmon_in_lcrit_alarm:
466 		case hwmon_in_crit_alarm:
467 			return 0444;
468 		case hwmon_in_lcrit:
469 		case hwmon_in_crit:
470 			return 0644;
471 		}
472 		break;
473 	case hwmon_curr:
474 		if (!data->shunt_uohms)
475 			return 0;
476 
477 		switch (attr) {
478 		case hwmon_curr_input:
479 		case hwmon_curr_lcrit_alarm:
480 		case hwmon_curr_crit_alarm:
481 			return 0444;
482 		case hwmon_curr_lcrit:
483 		case hwmon_curr_crit:
484 			return 0644;
485 		}
486 		break;
487 	case hwmon_power:
488 		if (!data->shunt_uohms)
489 			return 0;
490 
491 		switch (attr) {
492 		case hwmon_power_input:
493 		case hwmon_power_crit_alarm:
494 			return 0444;
495 		case hwmon_power_crit:
496 			return 0644;
497 		}
498 		break;
499 	default:
500 		break;
501 	}
502 	return 0;
503 }
504 
505 static const struct hwmon_channel_info * const tmp51x_info[] = {
506 	HWMON_CHANNEL_INFO(temp,
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_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
514 			   HWMON_T_CRIT_HYST),
515 	HWMON_CHANNEL_INFO(in,
516 			   HWMON_I_INPUT | HWMON_I_LCRIT | HWMON_I_LCRIT_ALARM |
517 			   HWMON_I_CRIT | HWMON_I_CRIT_ALARM),
518 	HWMON_CHANNEL_INFO(curr,
519 			   HWMON_C_INPUT | HWMON_C_LCRIT | HWMON_C_LCRIT_ALARM |
520 			   HWMON_C_CRIT | HWMON_C_CRIT_ALARM,
521 			   HWMON_C_INPUT),
522 	HWMON_CHANNEL_INFO(power,
523 			   HWMON_P_INPUT | HWMON_P_CRIT | HWMON_P_CRIT_ALARM),
524 	NULL
525 };
526 
527 static const struct hwmon_ops tmp51x_hwmon_ops = {
528 	.is_visible = tmp51x_is_visible,
529 	.read = tmp51x_read,
530 	.write = tmp51x_write,
531 };
532 
533 static const struct hwmon_chip_info tmp51x_chip_info = {
534 	.ops = &tmp51x_hwmon_ops,
535 	.info = tmp51x_info,
536 };
537 
538 /*
539  * Calibrate the tmp51x following the datasheet method
540  */
tmp51x_calibrate(struct tmp51x_data * data)541 static int tmp51x_calibrate(struct tmp51x_data *data)
542 {
543 	int vshunt_max = data->pga_gain * 40;
544 	u64 max_curr_ma;
545 	u32 div;
546 
547 	/*
548 	 * If shunt_uohms is equal to 0, the calibration should be set to 0.
549 	 * The consequence will be that the current and power measurement engine
550 	 * of the sensor will not work. Temperature and voltage sensing will
551 	 * continue to work.
552 	 */
553 	if (data->shunt_uohms == 0)
554 		return regmap_write(data->regmap, TMP51X_SHUNT_CALIBRATION, 0);
555 
556 	max_curr_ma = DIV_ROUND_CLOSEST_ULL(vshunt_max * MICRO, data->shunt_uohms);
557 
558 	/*
559 	 * Calculate the minimal bit resolution for the current and the power.
560 	 * Those values will be used during register interpretation.
561 	 */
562 	data->curr_lsb_ua = DIV_ROUND_CLOSEST_ULL(max_curr_ma * MILLI, 32767);
563 	data->pwr_lsb_uw = 20 * data->curr_lsb_ua;
564 
565 	div = DIV_ROUND_CLOSEST_ULL(data->curr_lsb_ua * data->shunt_uohms, MICRO);
566 
567 	return regmap_write(data->regmap, TMP51X_SHUNT_CALIBRATION,
568 			    DIV_ROUND_CLOSEST(40960, div));
569 }
570 
571 /*
572  * Initialize the configuration and calibration registers.
573  */
tmp51x_init(struct tmp51x_data * data)574 static int tmp51x_init(struct tmp51x_data *data)
575 {
576 	unsigned int regval;
577 	int ret = regmap_write(data->regmap, TMP51X_SHUNT_CONFIG,
578 			       data->shunt_config);
579 	if (ret < 0)
580 		return ret;
581 
582 	ret = regmap_write(data->regmap, TMP51X_TEMP_CONFIG, data->temp_config);
583 	if (ret < 0)
584 		return ret;
585 
586 	// nFactor configuration
587 	ret = regmap_update_bits(data->regmap, TMP51X_N_FACTOR_AND_HYST_1,
588 				 TMP51X_NFACTOR_MASK, data->nfactor[0] << 8);
589 	if (ret < 0)
590 		return ret;
591 
592 	ret = regmap_write(data->regmap, TMP51X_N_FACTOR_2,
593 			   data->nfactor[1] << 8);
594 	if (ret < 0)
595 		return ret;
596 
597 	if (data->max_channels == TMP513_MAX_CHANNELS) {
598 		ret = regmap_write(data->regmap, TMP513_N_FACTOR_3,
599 				   data->nfactor[2] << 8);
600 		if (ret < 0)
601 			return ret;
602 	}
603 
604 	ret = tmp51x_calibrate(data);
605 	if (ret < 0)
606 		return ret;
607 
608 	// Read the status register before using as the datasheet propose
609 	return regmap_read(data->regmap, TMP51X_STATUS, &regval);
610 }
611 
612 static const struct i2c_device_id tmp51x_id[] = {
613 	{ "tmp512", TMP512_MAX_CHANNELS },
614 	{ "tmp513", TMP513_MAX_CHANNELS },
615 	{ }
616 };
617 MODULE_DEVICE_TABLE(i2c, tmp51x_id);
618 
619 static const struct of_device_id tmp51x_of_match[] = {
620 	{ .compatible = "ti,tmp512", .data = (void *)TMP512_MAX_CHANNELS },
621 	{ .compatible = "ti,tmp513", .data = (void *)TMP513_MAX_CHANNELS },
622 	{ }
623 };
624 MODULE_DEVICE_TABLE(of, tmp51x_of_match);
625 
tmp51x_vbus_range_to_reg(struct device * dev,struct tmp51x_data * data)626 static int tmp51x_vbus_range_to_reg(struct device *dev,
627 				    struct tmp51x_data *data)
628 {
629 	if (data->vbus_range_uvolt == TMP51X_VBUS_RANGE_32V) {
630 		data->shunt_config |= TMP51X_BUS_VOLTAGE_MASK;
631 	} else if (data->vbus_range_uvolt == TMP51X_VBUS_RANGE_16V) {
632 		data->shunt_config &= ~TMP51X_BUS_VOLTAGE_MASK;
633 	} else {
634 		return dev_err_probe(dev, -EINVAL,
635 				     "ti,bus-range-microvolt is invalid: %u\n",
636 				     data->vbus_range_uvolt);
637 	}
638 	return 0;
639 }
640 
tmp51x_pga_gain_to_reg(struct device * dev,struct tmp51x_data * data)641 static int tmp51x_pga_gain_to_reg(struct device *dev, struct tmp51x_data *data)
642 {
643 	if (data->pga_gain == 8) {
644 		data->shunt_config |= CURRENT_SENSE_VOLTAGE_320_MASK;
645 	} else if (data->pga_gain == 4) {
646 		data->shunt_config |= CURRENT_SENSE_VOLTAGE_160_MASK;
647 	} else if (data->pga_gain == 2) {
648 		data->shunt_config |= CURRENT_SENSE_VOLTAGE_80_MASK;
649 	} else if (data->pga_gain == 1) {
650 		data->shunt_config |= CURRENT_SENSE_VOLTAGE_40_MASK;
651 	} else {
652 		return dev_err_probe(dev, -EINVAL,
653 				     "ti,pga-gain is invalid: %u\n", data->pga_gain);
654 	}
655 	return 0;
656 }
657 
tmp51x_read_properties(struct device * dev,struct tmp51x_data * data)658 static int tmp51x_read_properties(struct device *dev, struct tmp51x_data *data)
659 {
660 	int ret;
661 	u32 val;
662 
663 	ret = device_property_read_u32(dev, "shunt-resistor-micro-ohms", &val);
664 	data->shunt_uohms = (ret >= 0) ? val : TMP51X_SHUNT_VALUE_DEFAULT;
665 
666 	ret = device_property_read_u32(dev, "ti,bus-range-microvolt", &val);
667 	data->vbus_range_uvolt = (ret >= 0) ? val : TMP51X_VBUS_RANGE_DEFAULT;
668 	ret = tmp51x_vbus_range_to_reg(dev, data);
669 	if (ret < 0)
670 		return ret;
671 
672 	ret = device_property_read_u32(dev, "ti,pga-gain", &val);
673 	data->pga_gain = (ret >= 0) ? val : TMP51X_PGA_DEFAULT;
674 	ret = tmp51x_pga_gain_to_reg(dev, data);
675 	if (ret < 0)
676 		return ret;
677 
678 	device_property_read_u32_array(dev, "ti,nfactor", data->nfactor,
679 				       data->max_channels - 1);
680 
681 	// Check if shunt value is compatible with pga-gain
682 	if (data->shunt_uohms > data->pga_gain * 40 * MICRO) {
683 		return dev_err_probe(dev, -EINVAL,
684 				     "shunt-resistor: %u too big for pga_gain: %u\n",
685 				     data->shunt_uohms, data->pga_gain);
686 	}
687 
688 	return 0;
689 }
690 
tmp51x_use_default(struct tmp51x_data * data)691 static void tmp51x_use_default(struct tmp51x_data *data)
692 {
693 	data->vbus_range_uvolt = TMP51X_VBUS_RANGE_DEFAULT;
694 	data->pga_gain = TMP51X_PGA_DEFAULT;
695 	data->shunt_uohms = TMP51X_SHUNT_VALUE_DEFAULT;
696 }
697 
tmp51x_configure(struct device * dev,struct tmp51x_data * data)698 static int tmp51x_configure(struct device *dev, struct tmp51x_data *data)
699 {
700 	data->shunt_config = TMP51X_SHUNT_CONFIG_DEFAULT;
701 	data->temp_config = TMP51X_TEMP_CONFIG_DEFAULT(data->max_channels);
702 
703 	if (dev->of_node)
704 		return tmp51x_read_properties(dev, data);
705 
706 	tmp51x_use_default(data);
707 
708 	return 0;
709 }
710 
tmp51x_probe(struct i2c_client * client)711 static int tmp51x_probe(struct i2c_client *client)
712 {
713 	struct device *dev = &client->dev;
714 	struct tmp51x_data *data;
715 	struct device *hwmon_dev;
716 	int ret;
717 
718 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
719 	if (!data)
720 		return -ENOMEM;
721 
722 	data->max_channels = (uintptr_t)i2c_get_match_data(client);
723 
724 	ret = tmp51x_configure(dev, data);
725 	if (ret < 0)
726 		return dev_err_probe(dev, ret, "error configuring the device\n");
727 
728 	data->regmap = devm_regmap_init_i2c(client, &tmp51x_regmap_config);
729 	if (IS_ERR(data->regmap))
730 		return dev_err_probe(dev, PTR_ERR(data->regmap),
731 				     "failed to allocate register map\n");
732 
733 	ret = tmp51x_init(data);
734 	if (ret < 0)
735 		return dev_err_probe(dev, ret, "error configuring the device\n");
736 
737 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
738 							 data,
739 							 &tmp51x_chip_info,
740 							 NULL);
741 	if (IS_ERR(hwmon_dev))
742 		return PTR_ERR(hwmon_dev);
743 
744 	dev_dbg(dev, "power monitor %s\n", client->name);
745 
746 	return 0;
747 }
748 
749 static struct i2c_driver tmp51x_driver = {
750 	.driver = {
751 		.name	= "tmp51x",
752 		.of_match_table = tmp51x_of_match,
753 	},
754 	.probe		= tmp51x_probe,
755 	.id_table	= tmp51x_id,
756 };
757 
758 module_i2c_driver(tmp51x_driver);
759 
760 MODULE_AUTHOR("Eric Tremblay <etremblay@distechcontrols.com>");
761 MODULE_DESCRIPTION("tmp51x driver");
762 MODULE_LICENSE("GPL");
763