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/err.h>
23 #include <linux/hwmon.h>
24 #include <linux/i2c.h>
25 #include <linux/init.h>
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/regmap.h>
29 #include <linux/slab.h>
30 #include <linux/util_macros.h>
31 
32 // Common register definition
33 #define TMP51X_SHUNT_CONFIG		0x00
34 #define TMP51X_TEMP_CONFIG		0x01
35 #define TMP51X_STATUS			0x02
36 #define TMP51X_SMBUS_ALERT		0x03
37 #define TMP51X_SHUNT_CURRENT_RESULT	0x04
38 #define TMP51X_BUS_VOLTAGE_RESULT	0x05
39 #define TMP51X_POWER_RESULT		0x06
40 #define TMP51X_BUS_CURRENT_RESULT	0x07
41 #define TMP51X_LOCAL_TEMP_RESULT	0x08
42 #define TMP51X_REMOTE_TEMP_RESULT_1	0x09
43 #define TMP51X_REMOTE_TEMP_RESULT_2	0x0A
44 #define TMP51X_SHUNT_CURRENT_H_LIMIT	0x0C
45 #define TMP51X_SHUNT_CURRENT_L_LIMIT	0x0D
46 #define TMP51X_BUS_VOLTAGE_H_LIMIT	0x0E
47 #define TMP51X_BUS_VOLTAGE_L_LIMIT	0x0F
48 #define TMP51X_POWER_LIMIT		0x10
49 #define TMP51X_LOCAL_TEMP_LIMIT	0x11
50 #define TMP51X_REMOTE_TEMP_LIMIT_1	0x12
51 #define TMP51X_REMOTE_TEMP_LIMIT_2	0x13
52 #define TMP51X_SHUNT_CALIBRATION	0x15
53 #define TMP51X_N_FACTOR_AND_HYST_1	0x16
54 #define TMP51X_N_FACTOR_2		0x17
55 #define TMP51X_MAN_ID_REG		0xFE
56 #define TMP51X_DEVICE_ID_REG		0xFF
57 
58 // TMP513 specific register definition
59 #define TMP513_REMOTE_TEMP_RESULT_3	0x0B
60 #define TMP513_REMOTE_TEMP_LIMIT_3	0x14
61 #define TMP513_N_FACTOR_3		0x18
62 
63 // Common attrs, and NULL
64 #define TMP51X_MANUFACTURER_ID		0x55FF
65 
66 #define TMP512_DEVICE_ID		0x22FF
67 #define TMP513_DEVICE_ID		0x23FF
68 
69 // Default config
70 #define TMP51X_SHUNT_CONFIG_DEFAULT	0x399F
71 #define TMP51X_SHUNT_VALUE_DEFAULT	1000
72 #define TMP51X_VBUS_RANGE_DEFAULT	TMP51X_VBUS_RANGE_32V
73 #define TMP51X_PGA_DEFAULT		8
74 #define TMP51X_MAX_REGISTER_ADDR	0xFF
75 
76 #define TMP512_TEMP_CONFIG_DEFAULT	0xBF80
77 #define TMP513_TEMP_CONFIG_DEFAULT	0xFF80
78 
79 // Mask and shift
80 #define CURRENT_SENSE_VOLTAGE_320_MASK	0x1800
81 #define CURRENT_SENSE_VOLTAGE_160_MASK	0x1000
82 #define CURRENT_SENSE_VOLTAGE_80_MASK	0x0800
83 #define CURRENT_SENSE_VOLTAGE_40_MASK	0
84 
85 #define TMP51X_BUS_VOLTAGE_MASK		0x2000
86 #define TMP51X_NFACTOR_MASK		0xFF00
87 #define TMP51X_HYST_MASK		0x00FF
88 
89 #define TMP51X_BUS_VOLTAGE_SHIFT	3
90 #define TMP51X_TEMP_SHIFT		3
91 
92 // Alarms
93 #define TMP51X_SHUNT_CURRENT_H_LIMIT_POS	15
94 #define TMP51X_SHUNT_CURRENT_L_LIMIT_POS	14
95 #define TMP51X_BUS_VOLTAGE_H_LIMIT_POS		13
96 #define TMP51X_BUS_VOLTAGE_L_LIMIT_POS		12
97 #define TMP51X_POWER_LIMIT_POS			11
98 #define TMP51X_LOCAL_TEMP_LIMIT_POS		10
99 #define TMP51X_REMOTE_TEMP_LIMIT_1_POS		9
100 #define TMP51X_REMOTE_TEMP_LIMIT_2_POS		8
101 #define TMP513_REMOTE_TEMP_LIMIT_3_POS		7
102 
103 #define TMP51X_VBUS_RANGE_32V		32000000
104 #define TMP51X_VBUS_RANGE_16V		16000000
105 
106 // Max and Min value
107 #define MAX_BUS_VOLTAGE_32_LIMIT	32764
108 #define MAX_BUS_VOLTAGE_16_LIMIT	16382
109 
110 // Max possible value is -256 to +256 but datasheet indicated -40 to 125.
111 #define MAX_TEMP_LIMIT			125000
112 #define MIN_TEMP_LIMIT			-40000
113 
114 #define MAX_TEMP_HYST			127500
115 
116 static const u8 TMP51X_TEMP_INPUT[4] = {
117 	TMP51X_LOCAL_TEMP_RESULT,
118 	TMP51X_REMOTE_TEMP_RESULT_1,
119 	TMP51X_REMOTE_TEMP_RESULT_2,
120 	TMP513_REMOTE_TEMP_RESULT_3
121 };
122 
123 static const u8 TMP51X_TEMP_CRIT[4] = {
124 	TMP51X_LOCAL_TEMP_LIMIT,
125 	TMP51X_REMOTE_TEMP_LIMIT_1,
126 	TMP51X_REMOTE_TEMP_LIMIT_2,
127 	TMP513_REMOTE_TEMP_LIMIT_3
128 };
129 
130 static const u8 TMP51X_TEMP_CRIT_ALARM[4] = {
131 	TMP51X_LOCAL_TEMP_LIMIT_POS,
132 	TMP51X_REMOTE_TEMP_LIMIT_1_POS,
133 	TMP51X_REMOTE_TEMP_LIMIT_2_POS,
134 	TMP513_REMOTE_TEMP_LIMIT_3_POS
135 };
136 
137 static const u8 TMP51X_TEMP_CRIT_HYST[4] = {
138 	TMP51X_N_FACTOR_AND_HYST_1,
139 	TMP51X_N_FACTOR_AND_HYST_1,
140 	TMP51X_N_FACTOR_AND_HYST_1,
141 	TMP51X_N_FACTOR_AND_HYST_1
142 };
143 
144 static const u8 TMP51X_CURR_INPUT[2] = {
145 	TMP51X_SHUNT_CURRENT_RESULT,
146 	TMP51X_BUS_CURRENT_RESULT
147 };
148 
149 static struct regmap_config tmp51x_regmap_config = {
150 	.reg_bits = 8,
151 	.val_bits = 16,
152 	.max_register = TMP51X_MAX_REGISTER_ADDR,
153 };
154 
155 enum tmp51x_ids {
156 	tmp512, tmp513
157 };
158 
159 struct tmp51x_data {
160 	u16 shunt_config;
161 	u16 pga_gain;
162 	u32 vbus_range_uvolt;
163 
164 	u16 temp_config;
165 	u32 nfactor[3];
166 
167 	u32 shunt_uohms;
168 
169 	u32 curr_lsb_ua;
170 	u32 pwr_lsb_uw;
171 
172 	enum tmp51x_ids id;
173 	struct regmap *regmap;
174 };
175 
176 // Set the shift based on the gain 8=4, 4=3, 2=2, 1=1
tmp51x_get_pga_shift(struct tmp51x_data * data)177 static inline u8 tmp51x_get_pga_shift(struct tmp51x_data *data)
178 {
179 	return 5 - ffs(data->pga_gain);
180 }
181 
tmp51x_get_value(struct tmp51x_data * data,u8 reg,u8 pos,unsigned int regval,long * val)182 static int tmp51x_get_value(struct tmp51x_data *data, u8 reg, u8 pos,
183 			    unsigned int regval, long *val)
184 {
185 	switch (reg) {
186 	case TMP51X_STATUS:
187 		*val = (regval >> pos) & 1;
188 		break;
189 	case TMP51X_SHUNT_CURRENT_RESULT:
190 	case TMP51X_SHUNT_CURRENT_H_LIMIT:
191 	case TMP51X_SHUNT_CURRENT_L_LIMIT:
192 		/*
193 		 * The valus is read in voltage in the chip but reported as
194 		 * current to the user.
195 		 * 2's complement number shifted by one to four depending
196 		 * on the pga gain setting. 1lsb = 10uV
197 		 */
198 		*val = sign_extend32(regval, 17 - tmp51x_get_pga_shift(data));
199 		*val = DIV_ROUND_CLOSEST(*val * 10000, data->shunt_uohms);
200 		break;
201 	case TMP51X_BUS_VOLTAGE_RESULT:
202 	case TMP51X_BUS_VOLTAGE_H_LIMIT:
203 	case TMP51X_BUS_VOLTAGE_L_LIMIT:
204 		// 1lsb = 4mV
205 		*val = (regval >> TMP51X_BUS_VOLTAGE_SHIFT) * 4;
206 		break;
207 	case TMP51X_POWER_RESULT:
208 	case TMP51X_POWER_LIMIT:
209 		// Power = (current * BusVoltage) / 5000
210 		*val = regval * data->pwr_lsb_uw;
211 		break;
212 	case TMP51X_BUS_CURRENT_RESULT:
213 		// Current = (ShuntVoltage * CalibrationRegister) / 4096
214 		*val = sign_extend32(regval, 16) * data->curr_lsb_ua;
215 		*val = DIV_ROUND_CLOSEST(*val, 1000);
216 		break;
217 	case TMP51X_LOCAL_TEMP_RESULT:
218 	case TMP51X_REMOTE_TEMP_RESULT_1:
219 	case TMP51X_REMOTE_TEMP_RESULT_2:
220 	case TMP513_REMOTE_TEMP_RESULT_3:
221 	case TMP51X_LOCAL_TEMP_LIMIT:
222 	case TMP51X_REMOTE_TEMP_LIMIT_1:
223 	case TMP51X_REMOTE_TEMP_LIMIT_2:
224 	case TMP513_REMOTE_TEMP_LIMIT_3:
225 		// 1lsb = 0.0625 degrees centigrade
226 		*val = sign_extend32(regval, 16) >> TMP51X_TEMP_SHIFT;
227 		*val = DIV_ROUND_CLOSEST(*val * 625, 10);
228 		break;
229 	case TMP51X_N_FACTOR_AND_HYST_1:
230 		// 1lsb = 0.5 degrees centigrade
231 		*val = (regval & TMP51X_HYST_MASK) * 500;
232 		break;
233 	default:
234 		// Programmer goofed
235 		WARN_ON_ONCE(1);
236 		*val = 0;
237 		return -EOPNOTSUPP;
238 	}
239 
240 	return 0;
241 }
242 
tmp51x_set_value(struct tmp51x_data * data,u8 reg,long val)243 static int tmp51x_set_value(struct tmp51x_data *data, u8 reg, long val)
244 {
245 	int regval, max_val;
246 	u32 mask = 0;
247 
248 	switch (reg) {
249 	case TMP51X_SHUNT_CURRENT_H_LIMIT:
250 	case TMP51X_SHUNT_CURRENT_L_LIMIT:
251 		/*
252 		 * The user enter current value and we convert it to
253 		 * voltage. 1lsb = 10uV
254 		 */
255 		val = DIV_ROUND_CLOSEST(val * data->shunt_uohms, 10000);
256 		max_val = U16_MAX >> tmp51x_get_pga_shift(data);
257 		regval = clamp_val(val, -max_val, max_val);
258 		break;
259 	case TMP51X_BUS_VOLTAGE_H_LIMIT:
260 	case TMP51X_BUS_VOLTAGE_L_LIMIT:
261 		// 1lsb = 4mV
262 		max_val = (data->vbus_range_uvolt == TMP51X_VBUS_RANGE_32V) ?
263 			MAX_BUS_VOLTAGE_32_LIMIT : MAX_BUS_VOLTAGE_16_LIMIT;
264 
265 		val = clamp_val(DIV_ROUND_CLOSEST(val, 4), 0, max_val);
266 		regval = val << TMP51X_BUS_VOLTAGE_SHIFT;
267 		break;
268 	case TMP51X_POWER_LIMIT:
269 		regval = clamp_val(DIV_ROUND_CLOSEST(val, data->pwr_lsb_uw), 0,
270 				   U16_MAX);
271 		break;
272 	case TMP51X_LOCAL_TEMP_LIMIT:
273 	case TMP51X_REMOTE_TEMP_LIMIT_1:
274 	case TMP51X_REMOTE_TEMP_LIMIT_2:
275 	case TMP513_REMOTE_TEMP_LIMIT_3:
276 		// 1lsb = 0.0625 degrees centigrade
277 		val = clamp_val(val, MIN_TEMP_LIMIT, MAX_TEMP_LIMIT);
278 		regval = DIV_ROUND_CLOSEST(val * 10, 625) << TMP51X_TEMP_SHIFT;
279 		break;
280 	case TMP51X_N_FACTOR_AND_HYST_1:
281 		// 1lsb = 0.5 degrees centigrade
282 		val = clamp_val(val, 0, MAX_TEMP_HYST);
283 		regval = DIV_ROUND_CLOSEST(val, 500);
284 		mask = TMP51X_HYST_MASK;
285 		break;
286 	default:
287 		// Programmer goofed
288 		WARN_ON_ONCE(1);
289 		return -EOPNOTSUPP;
290 	}
291 
292 	if (mask == 0)
293 		return regmap_write(data->regmap, reg, regval);
294 	else
295 		return regmap_update_bits(data->regmap, reg, mask, regval);
296 }
297 
tmp51x_get_reg(enum hwmon_sensor_types type,u32 attr,int channel)298 static u8 tmp51x_get_reg(enum hwmon_sensor_types type, u32 attr, int channel)
299 {
300 	switch (type) {
301 	case hwmon_temp:
302 		switch (attr) {
303 		case hwmon_temp_input:
304 			return TMP51X_TEMP_INPUT[channel];
305 		case hwmon_temp_crit_alarm:
306 			return TMP51X_STATUS;
307 		case hwmon_temp_crit:
308 			return TMP51X_TEMP_CRIT[channel];
309 		case hwmon_temp_crit_hyst:
310 			return TMP51X_TEMP_CRIT_HYST[channel];
311 		}
312 		break;
313 	case hwmon_in:
314 		switch (attr) {
315 		case hwmon_in_input:
316 			return TMP51X_BUS_VOLTAGE_RESULT;
317 		case hwmon_in_lcrit_alarm:
318 		case hwmon_in_crit_alarm:
319 			return TMP51X_STATUS;
320 		case hwmon_in_lcrit:
321 			return TMP51X_BUS_VOLTAGE_L_LIMIT;
322 		case hwmon_in_crit:
323 			return TMP51X_BUS_VOLTAGE_H_LIMIT;
324 		}
325 		break;
326 	case hwmon_curr:
327 		switch (attr) {
328 		case hwmon_curr_input:
329 			return TMP51X_CURR_INPUT[channel];
330 		case hwmon_curr_lcrit_alarm:
331 		case hwmon_curr_crit_alarm:
332 			return TMP51X_STATUS;
333 		case hwmon_curr_lcrit:
334 			return TMP51X_SHUNT_CURRENT_L_LIMIT;
335 		case hwmon_curr_crit:
336 			return TMP51X_SHUNT_CURRENT_H_LIMIT;
337 		}
338 		break;
339 	case hwmon_power:
340 		switch (attr) {
341 		case hwmon_power_input:
342 			return TMP51X_POWER_RESULT;
343 		case hwmon_power_crit_alarm:
344 			return TMP51X_STATUS;
345 		case hwmon_power_crit:
346 			return TMP51X_POWER_LIMIT;
347 		}
348 		break;
349 	default:
350 		break;
351 	}
352 
353 	return 0;
354 }
355 
tmp51x_get_status_pos(enum hwmon_sensor_types type,u32 attr,int channel)356 static u8 tmp51x_get_status_pos(enum hwmon_sensor_types type, u32 attr,
357 				int channel)
358 {
359 	switch (type) {
360 	case hwmon_temp:
361 		switch (attr) {
362 		case hwmon_temp_crit_alarm:
363 			return TMP51X_TEMP_CRIT_ALARM[channel];
364 		}
365 		break;
366 	case hwmon_in:
367 		switch (attr) {
368 		case hwmon_in_lcrit_alarm:
369 			return TMP51X_BUS_VOLTAGE_L_LIMIT_POS;
370 		case hwmon_in_crit_alarm:
371 			return TMP51X_BUS_VOLTAGE_H_LIMIT_POS;
372 		}
373 		break;
374 	case hwmon_curr:
375 		switch (attr) {
376 		case hwmon_curr_lcrit_alarm:
377 			return TMP51X_SHUNT_CURRENT_L_LIMIT_POS;
378 		case hwmon_curr_crit_alarm:
379 			return TMP51X_SHUNT_CURRENT_H_LIMIT_POS;
380 		}
381 		break;
382 	case hwmon_power:
383 		switch (attr) {
384 		case hwmon_power_crit_alarm:
385 			return TMP51X_POWER_LIMIT_POS;
386 		}
387 		break;
388 	default:
389 		break;
390 	}
391 
392 	return 0;
393 }
394 
tmp51x_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)395 static int tmp51x_read(struct device *dev, enum hwmon_sensor_types type,
396 		       u32 attr, int channel, long *val)
397 {
398 	struct tmp51x_data *data = dev_get_drvdata(dev);
399 	int ret;
400 	u32 regval;
401 	u8 pos = 0, reg = 0;
402 
403 	reg = tmp51x_get_reg(type, attr, channel);
404 	if (reg == 0)
405 		return -EOPNOTSUPP;
406 
407 	if (reg == TMP51X_STATUS)
408 		pos = tmp51x_get_status_pos(type, attr, channel);
409 
410 	ret = regmap_read(data->regmap, reg, &regval);
411 	if (ret < 0)
412 		return ret;
413 
414 	return tmp51x_get_value(data, reg, pos, regval, val);
415 }
416 
tmp51x_write(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long val)417 static int tmp51x_write(struct device *dev, enum hwmon_sensor_types type,
418 			u32 attr, int channel, long val)
419 {
420 	u8 reg = 0;
421 
422 	reg = tmp51x_get_reg(type, attr, channel);
423 	if (reg == 0)
424 		return -EOPNOTSUPP;
425 
426 	return tmp51x_set_value(dev_get_drvdata(dev), reg, val);
427 }
428 
tmp51x_is_visible(const void * _data,enum hwmon_sensor_types type,u32 attr,int channel)429 static umode_t tmp51x_is_visible(const void *_data,
430 				 enum hwmon_sensor_types type, u32 attr,
431 				 int channel)
432 {
433 	const struct tmp51x_data *data = _data;
434 
435 	switch (type) {
436 	case hwmon_temp:
437 		if (data->id == tmp512 && channel == 3)
438 			return 0;
439 		switch (attr) {
440 		case hwmon_temp_input:
441 		case hwmon_temp_crit_alarm:
442 			return 0444;
443 		case hwmon_temp_crit:
444 			return 0644;
445 		case hwmon_temp_crit_hyst:
446 			if (channel == 0)
447 				return 0644;
448 			return 0444;
449 		}
450 		break;
451 	case hwmon_in:
452 		switch (attr) {
453 		case hwmon_in_input:
454 		case hwmon_in_lcrit_alarm:
455 		case hwmon_in_crit_alarm:
456 			return 0444;
457 		case hwmon_in_lcrit:
458 		case hwmon_in_crit:
459 			return 0644;
460 		}
461 		break;
462 	case hwmon_curr:
463 		if (!data->shunt_uohms)
464 			return 0;
465 
466 		switch (attr) {
467 		case hwmon_curr_input:
468 		case hwmon_curr_lcrit_alarm:
469 		case hwmon_curr_crit_alarm:
470 			return 0444;
471 		case hwmon_curr_lcrit:
472 		case hwmon_curr_crit:
473 			return 0644;
474 		}
475 		break;
476 	case hwmon_power:
477 		if (!data->shunt_uohms)
478 			return 0;
479 
480 		switch (attr) {
481 		case hwmon_power_input:
482 		case hwmon_power_crit_alarm:
483 			return 0444;
484 		case hwmon_power_crit:
485 			return 0644;
486 		}
487 		break;
488 	default:
489 		break;
490 	}
491 	return 0;
492 }
493 
494 static const struct hwmon_channel_info * const tmp51x_info[] = {
495 	HWMON_CHANNEL_INFO(temp,
496 			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
497 			   HWMON_T_CRIT_HYST,
498 			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
499 			   HWMON_T_CRIT_HYST,
500 			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
501 			   HWMON_T_CRIT_HYST,
502 			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
503 			   HWMON_T_CRIT_HYST),
504 	HWMON_CHANNEL_INFO(in,
505 			   HWMON_I_INPUT | HWMON_I_LCRIT | HWMON_I_LCRIT_ALARM |
506 			   HWMON_I_CRIT | HWMON_I_CRIT_ALARM),
507 	HWMON_CHANNEL_INFO(curr,
508 			   HWMON_C_INPUT | HWMON_C_LCRIT | HWMON_C_LCRIT_ALARM |
509 			   HWMON_C_CRIT | HWMON_C_CRIT_ALARM,
510 			   HWMON_C_INPUT),
511 	HWMON_CHANNEL_INFO(power,
512 			   HWMON_P_INPUT | HWMON_P_CRIT | HWMON_P_CRIT_ALARM),
513 	NULL
514 };
515 
516 static const struct hwmon_ops tmp51x_hwmon_ops = {
517 	.is_visible = tmp51x_is_visible,
518 	.read = tmp51x_read,
519 	.write = tmp51x_write,
520 };
521 
522 static const struct hwmon_chip_info tmp51x_chip_info = {
523 	.ops = &tmp51x_hwmon_ops,
524 	.info = tmp51x_info,
525 };
526 
527 /*
528  * Calibrate the tmp51x following the datasheet method
529  */
tmp51x_calibrate(struct tmp51x_data * data)530 static int tmp51x_calibrate(struct tmp51x_data *data)
531 {
532 	int vshunt_max = data->pga_gain * 40;
533 	u64 max_curr_ma;
534 	u32 div;
535 
536 	/*
537 	 * If shunt_uohms is equal to 0, the calibration should be set to 0.
538 	 * The consequence will be that the current and power measurement engine
539 	 * of the sensor will not work. Temperature and voltage sensing will
540 	 * continue to work.
541 	 */
542 	if (data->shunt_uohms == 0)
543 		return regmap_write(data->regmap, TMP51X_SHUNT_CALIBRATION, 0);
544 
545 	max_curr_ma = DIV_ROUND_CLOSEST_ULL(vshunt_max * 1000 * 1000,
546 					    data->shunt_uohms);
547 
548 	/*
549 	 * Calculate the minimal bit resolution for the current and the power.
550 	 * Those values will be used during register interpretation.
551 	 */
552 	data->curr_lsb_ua = DIV_ROUND_CLOSEST_ULL(max_curr_ma * 1000, 32767);
553 	data->pwr_lsb_uw = 20 * data->curr_lsb_ua;
554 
555 	div = DIV_ROUND_CLOSEST_ULL(data->curr_lsb_ua * data->shunt_uohms,
556 				    1000 * 1000);
557 
558 	return regmap_write(data->regmap, TMP51X_SHUNT_CALIBRATION,
559 			    DIV_ROUND_CLOSEST(40960, div));
560 }
561 
562 /*
563  * Initialize the configuration and calibration registers.
564  */
tmp51x_init(struct tmp51x_data * data)565 static int tmp51x_init(struct tmp51x_data *data)
566 {
567 	unsigned int regval;
568 	int ret = regmap_write(data->regmap, TMP51X_SHUNT_CONFIG,
569 			       data->shunt_config);
570 	if (ret < 0)
571 		return ret;
572 
573 	ret = regmap_write(data->regmap, TMP51X_TEMP_CONFIG, data->temp_config);
574 	if (ret < 0)
575 		return ret;
576 
577 	// nFactor configuration
578 	ret = regmap_update_bits(data->regmap, TMP51X_N_FACTOR_AND_HYST_1,
579 				 TMP51X_NFACTOR_MASK, data->nfactor[0] << 8);
580 	if (ret < 0)
581 		return ret;
582 
583 	ret = regmap_write(data->regmap, TMP51X_N_FACTOR_2,
584 			   data->nfactor[1] << 8);
585 	if (ret < 0)
586 		return ret;
587 
588 	if (data->id == tmp513) {
589 		ret = regmap_write(data->regmap, TMP513_N_FACTOR_3,
590 				   data->nfactor[2] << 8);
591 		if (ret < 0)
592 			return ret;
593 	}
594 
595 	ret = tmp51x_calibrate(data);
596 	if (ret < 0)
597 		return ret;
598 
599 	// Read the status register before using as the datasheet propose
600 	return regmap_read(data->regmap, TMP51X_STATUS, &regval);
601 }
602 
603 static const struct i2c_device_id tmp51x_id[] = {
604 	{ "tmp512", tmp512 },
605 	{ "tmp513", tmp513 },
606 	{ }
607 };
608 MODULE_DEVICE_TABLE(i2c, tmp51x_id);
609 
610 static const struct of_device_id tmp51x_of_match[] = {
611 	{
612 		.compatible = "ti,tmp512",
613 		.data = (void *)tmp512
614 	},
615 	{
616 		.compatible = "ti,tmp513",
617 		.data = (void *)tmp513
618 	},
619 	{ },
620 };
621 MODULE_DEVICE_TABLE(of, tmp51x_of_match);
622 
tmp51x_vbus_range_to_reg(struct device * dev,struct tmp51x_data * data)623 static int tmp51x_vbus_range_to_reg(struct device *dev,
624 				    struct tmp51x_data *data)
625 {
626 	if (data->vbus_range_uvolt == TMP51X_VBUS_RANGE_32V) {
627 		data->shunt_config |= TMP51X_BUS_VOLTAGE_MASK;
628 	} else if (data->vbus_range_uvolt == TMP51X_VBUS_RANGE_16V) {
629 		data->shunt_config &= ~TMP51X_BUS_VOLTAGE_MASK;
630 	} else {
631 		dev_err(dev, "ti,bus-range-microvolt is invalid: %u\n",
632 			data->vbus_range_uvolt);
633 		return -EINVAL;
634 	}
635 	return 0;
636 }
637 
tmp51x_pga_gain_to_reg(struct device * dev,struct tmp51x_data * data)638 static int tmp51x_pga_gain_to_reg(struct device *dev, struct tmp51x_data *data)
639 {
640 	if (data->pga_gain == 8) {
641 		data->shunt_config |= CURRENT_SENSE_VOLTAGE_320_MASK;
642 	} else if (data->pga_gain == 4) {
643 		data->shunt_config |= CURRENT_SENSE_VOLTAGE_160_MASK;
644 	} else if (data->pga_gain == 2) {
645 		data->shunt_config |= CURRENT_SENSE_VOLTAGE_80_MASK;
646 	} else if (data->pga_gain == 1) {
647 		data->shunt_config |= CURRENT_SENSE_VOLTAGE_40_MASK;
648 	} else {
649 		dev_err(dev, "ti,pga-gain is invalid: %u\n", data->pga_gain);
650 		return -EINVAL;
651 	}
652 	return 0;
653 }
654 
tmp51x_read_properties(struct device * dev,struct tmp51x_data * data)655 static int tmp51x_read_properties(struct device *dev, struct tmp51x_data *data)
656 {
657 	int ret;
658 	u32 nfactor[3];
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 	ret = device_property_read_u32_array(dev, "ti,nfactor", nfactor,
677 					    (data->id == tmp513) ? 3 : 2);
678 	if (ret >= 0)
679 		memcpy(data->nfactor, nfactor, (data->id == tmp513) ? 3 : 2);
680 
681 	// Check if shunt value is compatible with pga-gain
682 	if (data->shunt_uohms > data->pga_gain * 40 * 1000 * 1000) {
683 		dev_err(dev, "shunt-resistor: %u too big for pga_gain: %u\n",
684 			data->shunt_uohms, data->pga_gain);
685 		return -EINVAL;
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 = (data->id == tmp513) ?
702 			TMP513_TEMP_CONFIG_DEFAULT : TMP512_TEMP_CONFIG_DEFAULT;
703 
704 	if (dev->of_node)
705 		return tmp51x_read_properties(dev, data);
706 
707 	tmp51x_use_default(data);
708 
709 	return 0;
710 }
711 
tmp51x_probe(struct i2c_client * client)712 static int tmp51x_probe(struct i2c_client *client)
713 {
714 	struct device *dev = &client->dev;
715 	struct tmp51x_data *data;
716 	struct device *hwmon_dev;
717 	int ret;
718 
719 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
720 	if (!data)
721 		return -ENOMEM;
722 
723 	data->id = (uintptr_t)i2c_get_match_data(client);
724 
725 	ret = tmp51x_configure(dev, data);
726 	if (ret < 0) {
727 		dev_err(dev, "error configuring the device: %d\n", ret);
728 		return ret;
729 	}
730 
731 	data->regmap = devm_regmap_init_i2c(client, &tmp51x_regmap_config);
732 	if (IS_ERR(data->regmap)) {
733 		dev_err(dev, "failed to allocate register map\n");
734 		return PTR_ERR(data->regmap);
735 	}
736 
737 	ret = tmp51x_init(data);
738 	if (ret < 0) {
739 		dev_err(dev, "error configuring the device: %d\n", ret);
740 		return -ENODEV;
741 	}
742 
743 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
744 							 data,
745 							 &tmp51x_chip_info,
746 							 NULL);
747 	if (IS_ERR(hwmon_dev))
748 		return PTR_ERR(hwmon_dev);
749 
750 	dev_dbg(dev, "power monitor %s\n", client->name);
751 
752 	return 0;
753 }
754 
755 static struct i2c_driver tmp51x_driver = {
756 	.driver = {
757 		.name	= "tmp51x",
758 		.of_match_table = tmp51x_of_match,
759 	},
760 	.probe		= tmp51x_probe,
761 	.id_table	= tmp51x_id,
762 };
763 
764 module_i2c_driver(tmp51x_driver);
765 
766 MODULE_AUTHOR("Eric Tremblay <etremblay@distechcontrols.com>");
767 MODULE_DESCRIPTION("tmp51x driver");
768 MODULE_LICENSE("GPL");
769