xref: /openbmc/linux/drivers/hwmon/nct7904.c (revision 015d239a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * nct7904.c - driver for Nuvoton NCT7904D.
4  *
5  * Copyright (c) 2015 Kontron
6  * Author: Vadim V. Vlasov <vvlasov@dev.rtsoft.ru>
7  *
8  * Copyright (c) 2019 Advantech
9  * Author: Amy.Shih <amy.shih@advantech.com.tw>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/device.h>
14 #include <linux/init.h>
15 #include <linux/i2c.h>
16 #include <linux/mutex.h>
17 #include <linux/hwmon.h>
18 
19 #define VENDOR_ID_REG		0x7A	/* Any bank */
20 #define NUVOTON_ID		0x50
21 #define CHIP_ID_REG		0x7B	/* Any bank */
22 #define NCT7904_ID		0xC5
23 #define DEVICE_ID_REG		0x7C	/* Any bank */
24 
25 #define BANK_SEL_REG		0xFF
26 #define BANK_0			0x00
27 #define BANK_1			0x01
28 #define BANK_2			0x02
29 #define BANK_3			0x03
30 #define BANK_4			0x04
31 #define BANK_MAX		0x04
32 
33 #define FANIN_MAX		12	/* Counted from 1 */
34 #define VSEN_MAX		21	/* VSEN1..14, 3VDD, VBAT, V3VSB,
35 					   LTD (not a voltage), VSEN17..19 */
36 #define FANCTL_MAX		4	/* Counted from 1 */
37 #define TCPU_MAX		8	/* Counted from 1 */
38 #define TEMP_MAX		4	/* Counted from 1 */
39 
40 #define VT_ADC_CTRL0_REG	0x20	/* Bank 0 */
41 #define VT_ADC_CTRL1_REG	0x21	/* Bank 0 */
42 #define VT_ADC_CTRL2_REG	0x22	/* Bank 0 */
43 #define FANIN_CTRL0_REG		0x24
44 #define FANIN_CTRL1_REG		0x25
45 #define DTS_T_CTRL0_REG		0x26
46 #define DTS_T_CTRL1_REG		0x27
47 #define VT_ADC_MD_REG		0x2E
48 
49 #define VSEN1_HV_LL_REG		0x02	/* Bank 1; 2 regs (HV/LV) per sensor */
50 #define VSEN1_LV_LL_REG		0x03	/* Bank 1; 2 regs (HV/LV) per sensor */
51 #define VSEN1_HV_HL_REG		0x00	/* Bank 1; 2 regs (HV/LV) per sensor */
52 #define VSEN1_LV_HL_REG		0x01	/* Bank 1; 2 regs (HV/LV) per sensor */
53 #define SMI_STS1_REG		0xC1	/* Bank 0; SMI Status Register */
54 #define SMI_STS3_REG		0xC3	/* Bank 0; SMI Status Register */
55 #define SMI_STS5_REG		0xC5	/* Bank 0; SMI Status Register */
56 #define SMI_STS7_REG		0xC7	/* Bank 0; SMI Status Register */
57 #define SMI_STS8_REG		0xC8	/* Bank 0; SMI Status Register */
58 
59 #define VSEN1_HV_REG		0x40	/* Bank 0; 2 regs (HV/LV) per sensor */
60 #define TEMP_CH1_HV_REG		0x42	/* Bank 0; same as VSEN2_HV */
61 #define LTD_HV_REG		0x62	/* Bank 0; 2 regs in VSEN range */
62 #define LTD_HV_HL_REG		0x44	/* Bank 1; 1 reg for LTD */
63 #define LTD_LV_HL_REG		0x45	/* Bank 1; 1 reg for LTD */
64 #define LTD_HV_LL_REG		0x46	/* Bank 1; 1 reg for LTD */
65 #define LTD_LV_LL_REG		0x47	/* Bank 1; 1 reg for LTD */
66 #define TEMP_CH1_CH_REG		0x05	/* Bank 1; 1 reg for LTD */
67 #define TEMP_CH1_W_REG		0x06	/* Bank 1; 1 reg for LTD */
68 #define TEMP_CH1_WH_REG		0x07	/* Bank 1; 1 reg for LTD */
69 #define TEMP_CH1_C_REG		0x04	/* Bank 1; 1 reg per sensor */
70 #define DTS_T_CPU1_C_REG	0x90	/* Bank 1; 1 reg per sensor */
71 #define DTS_T_CPU1_CH_REG	0x91	/* Bank 1; 1 reg per sensor */
72 #define DTS_T_CPU1_W_REG	0x92	/* Bank 1; 1 reg per sensor */
73 #define DTS_T_CPU1_WH_REG	0x93	/* Bank 1; 1 reg per sensor */
74 #define FANIN1_HV_REG		0x80	/* Bank 0; 2 regs (HV/LV) per sensor */
75 #define FANIN1_HV_HL_REG	0x60	/* Bank 1; 2 regs (HV/LV) per sensor */
76 #define FANIN1_LV_HL_REG	0x61	/* Bank 1; 2 regs (HV/LV) per sensor */
77 #define T_CPU1_HV_REG		0xA0	/* Bank 0; 2 regs (HV/LV) per sensor */
78 
79 #define PRTS_REG		0x03	/* Bank 2 */
80 #define PFE_REG			0x00	/* Bank 2; PECI Function Enable */
81 #define TSI_CTRL_REG		0x50	/* Bank 2; TSI Control Register */
82 #define FANCTL1_FMR_REG		0x00	/* Bank 3; 1 reg per channel */
83 #define FANCTL1_OUT_REG		0x10	/* Bank 3; 1 reg per channel */
84 
85 #define VOLT_MONITOR_MODE	0x0
86 #define THERMAL_DIODE_MODE	0x1
87 #define THERMISTOR_MODE		0x3
88 
89 #define ENABLE_TSI	BIT(1)
90 
91 static const unsigned short normal_i2c[] = {
92 	0x2d, 0x2e, I2C_CLIENT_END
93 };
94 
95 struct nct7904_data {
96 	struct i2c_client *client;
97 	struct mutex bank_lock;
98 	int bank_sel;
99 	u32 fanin_mask;
100 	u32 vsen_mask;
101 	u32 tcpu_mask;
102 	u8 fan_mode[FANCTL_MAX];
103 	u8 enable_dts;
104 	u8 has_dts;
105 	u8 temp_mode; /* 0: TR mode, 1: TD mode */
106 	u8 fan_alarm[2];
107 	u8 vsen_alarm[3];
108 };
109 
110 /* Access functions */
111 static int nct7904_bank_lock(struct nct7904_data *data, unsigned int bank)
112 {
113 	int ret;
114 
115 	mutex_lock(&data->bank_lock);
116 	if (data->bank_sel == bank)
117 		return 0;
118 	ret = i2c_smbus_write_byte_data(data->client, BANK_SEL_REG, bank);
119 	if (ret == 0)
120 		data->bank_sel = bank;
121 	else
122 		data->bank_sel = -1;
123 	return ret;
124 }
125 
126 static inline void nct7904_bank_release(struct nct7904_data *data)
127 {
128 	mutex_unlock(&data->bank_lock);
129 }
130 
131 /* Read 1-byte register. Returns unsigned reg or -ERRNO on error. */
132 static int nct7904_read_reg(struct nct7904_data *data,
133 			    unsigned int bank, unsigned int reg)
134 {
135 	struct i2c_client *client = data->client;
136 	int ret;
137 
138 	ret = nct7904_bank_lock(data, bank);
139 	if (ret == 0)
140 		ret = i2c_smbus_read_byte_data(client, reg);
141 
142 	nct7904_bank_release(data);
143 	return ret;
144 }
145 
146 /*
147  * Read 2-byte register. Returns register in big-endian format or
148  * -ERRNO on error.
149  */
150 static int nct7904_read_reg16(struct nct7904_data *data,
151 			      unsigned int bank, unsigned int reg)
152 {
153 	struct i2c_client *client = data->client;
154 	int ret, hi;
155 
156 	ret = nct7904_bank_lock(data, bank);
157 	if (ret == 0) {
158 		ret = i2c_smbus_read_byte_data(client, reg);
159 		if (ret >= 0) {
160 			hi = ret;
161 			ret = i2c_smbus_read_byte_data(client, reg + 1);
162 			if (ret >= 0)
163 				ret |= hi << 8;
164 		}
165 	}
166 
167 	nct7904_bank_release(data);
168 	return ret;
169 }
170 
171 /* Write 1-byte register. Returns 0 or -ERRNO on error. */
172 static int nct7904_write_reg(struct nct7904_data *data,
173 			     unsigned int bank, unsigned int reg, u8 val)
174 {
175 	struct i2c_client *client = data->client;
176 	int ret;
177 
178 	ret = nct7904_bank_lock(data, bank);
179 	if (ret == 0)
180 		ret = i2c_smbus_write_byte_data(client, reg, val);
181 
182 	nct7904_bank_release(data);
183 	return ret;
184 }
185 
186 static int nct7904_read_fan(struct device *dev, u32 attr, int channel,
187 			    long *val)
188 {
189 	struct nct7904_data *data = dev_get_drvdata(dev);
190 	unsigned int cnt, rpm;
191 	int ret;
192 
193 	switch (attr) {
194 	case hwmon_fan_input:
195 		ret = nct7904_read_reg16(data, BANK_0,
196 					 FANIN1_HV_REG + channel * 2);
197 		if (ret < 0)
198 			return ret;
199 		cnt = ((ret & 0xff00) >> 3) | (ret & 0x1f);
200 		if (cnt == 0x1fff)
201 			rpm = 0;
202 		else
203 			rpm = 1350000 / cnt;
204 		*val = rpm;
205 		return 0;
206 	case hwmon_fan_min:
207 		ret = nct7904_read_reg16(data, BANK_1,
208 					 FANIN1_HV_HL_REG + channel * 2);
209 		if (ret < 0)
210 			return ret;
211 		cnt = ((ret & 0xff00) >> 3) | (ret & 0x1f);
212 		if (cnt == 0x1fff)
213 			rpm = 0;
214 		else
215 			rpm = 1350000 / cnt;
216 		*val = rpm;
217 		return 0;
218 	case hwmon_fan_alarm:
219 		ret = nct7904_read_reg(data, BANK_0,
220 				       SMI_STS5_REG + (channel >> 3));
221 		if (ret < 0)
222 			return ret;
223 		if (!data->fan_alarm[channel >> 3])
224 			data->fan_alarm[channel >> 3] = ret & 0xff;
225 		else
226 			/* If there is new alarm showing up */
227 			data->fan_alarm[channel >> 3] |= (ret & 0xff);
228 		*val = (data->fan_alarm[channel >> 3] >> (channel & 0x07)) & 1;
229 		/* Needs to clean the alarm if alarm existing */
230 		if (*val)
231 			data->fan_alarm[channel >> 3] ^= 1 << (channel & 0x07);
232 		return 0;
233 	default:
234 		return -EOPNOTSUPP;
235 	}
236 }
237 
238 static umode_t nct7904_fan_is_visible(const void *_data, u32 attr, int channel)
239 {
240 	const struct nct7904_data *data = _data;
241 
242 	switch (attr) {
243 	case hwmon_fan_input:
244 	case hwmon_fan_alarm:
245 		if (data->fanin_mask & (1 << channel))
246 			return 0444;
247 		break;
248 	case hwmon_fan_min:
249 		if (data->fanin_mask & (1 << channel))
250 			return 0644;
251 		break;
252 	default:
253 		break;
254 	}
255 
256 	return 0;
257 }
258 
259 static u8 nct7904_chan_to_index[] = {
260 	0,	/* Not used */
261 	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
262 	18, 19, 20, 16
263 };
264 
265 static int nct7904_read_in(struct device *dev, u32 attr, int channel,
266 			   long *val)
267 {
268 	struct nct7904_data *data = dev_get_drvdata(dev);
269 	int ret, volt, index;
270 
271 	index = nct7904_chan_to_index[channel];
272 
273 	switch (attr) {
274 	case hwmon_in_input:
275 		ret = nct7904_read_reg16(data, BANK_0,
276 					 VSEN1_HV_REG + index * 2);
277 		if (ret < 0)
278 			return ret;
279 		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
280 		if (index < 14)
281 			volt *= 2; /* 0.002V scale */
282 		else
283 			volt *= 6; /* 0.006V scale */
284 		*val = volt;
285 		return 0;
286 	case hwmon_in_min:
287 		ret = nct7904_read_reg16(data, BANK_1,
288 					 VSEN1_HV_LL_REG + index * 4);
289 		if (ret < 0)
290 			return ret;
291 		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
292 		if (index < 14)
293 			volt *= 2; /* 0.002V scale */
294 		else
295 			volt *= 6; /* 0.006V scale */
296 		*val = volt;
297 		return 0;
298 	case hwmon_in_max:
299 		ret = nct7904_read_reg16(data, BANK_1,
300 					 VSEN1_HV_HL_REG + index * 4);
301 		if (ret < 0)
302 			return ret;
303 		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
304 		if (index < 14)
305 			volt *= 2; /* 0.002V scale */
306 		else
307 			volt *= 6; /* 0.006V scale */
308 		*val = volt;
309 		return 0;
310 	case hwmon_in_alarm:
311 		ret = nct7904_read_reg(data, BANK_0,
312 				       SMI_STS1_REG + (index >> 3));
313 		if (ret < 0)
314 			return ret;
315 		if (!data->vsen_alarm[index >> 3])
316 			data->vsen_alarm[index >> 3] = ret & 0xff;
317 		else
318 			/* If there is new alarm showing up */
319 			data->vsen_alarm[index >> 3] |= (ret & 0xff);
320 		*val = (data->vsen_alarm[index >> 3] >> (index & 0x07)) & 1;
321 		/* Needs to clean the alarm if alarm existing */
322 		if (*val)
323 			data->vsen_alarm[index >> 3] ^= 1 << (index & 0x07);
324 		return 0;
325 	default:
326 		return -EOPNOTSUPP;
327 	}
328 }
329 
330 static umode_t nct7904_in_is_visible(const void *_data, u32 attr, int channel)
331 {
332 	const struct nct7904_data *data = _data;
333 	int index = nct7904_chan_to_index[channel];
334 
335 	switch (attr) {
336 	case hwmon_in_input:
337 	case hwmon_in_alarm:
338 		if (channel > 0 && (data->vsen_mask & BIT(index)))
339 			return 0444;
340 		break;
341 	case hwmon_in_min:
342 	case hwmon_in_max:
343 		if (channel > 0 && (data->vsen_mask & BIT(index)))
344 			return 0644;
345 		break;
346 	default:
347 		break;
348 	}
349 
350 	return 0;
351 }
352 
353 static int nct7904_read_temp(struct device *dev, u32 attr, int channel,
354 			     long *val)
355 {
356 	struct nct7904_data *data = dev_get_drvdata(dev);
357 	int ret, temp;
358 	unsigned int reg1, reg2, reg3;
359 
360 	switch (attr) {
361 	case hwmon_temp_input:
362 		if (channel == 4)
363 			ret = nct7904_read_reg16(data, BANK_0, LTD_HV_REG);
364 		else if (channel < 5)
365 			ret = nct7904_read_reg16(data, BANK_0,
366 						 TEMP_CH1_HV_REG + channel * 4);
367 		else
368 			ret = nct7904_read_reg16(data, BANK_0,
369 						 T_CPU1_HV_REG + (channel - 5)
370 						 * 2);
371 		if (ret < 0)
372 			return ret;
373 		temp = ((ret & 0xff00) >> 5) | (ret & 0x7);
374 		*val = sign_extend32(temp, 10) * 125;
375 		return 0;
376 	case hwmon_temp_alarm:
377 		if (channel == 4) {
378 			ret = nct7904_read_reg(data, BANK_0,
379 					       SMI_STS3_REG);
380 			if (ret < 0)
381 				return ret;
382 			*val = (ret >> 1) & 1;
383 		} else if (channel < 4) {
384 			ret = nct7904_read_reg(data, BANK_0,
385 					       SMI_STS1_REG);
386 			if (ret < 0)
387 				return ret;
388 			*val = (ret >> (((channel * 2) + 1) & 0x07)) & 1;
389 		} else {
390 			if ((channel - 5) < 4) {
391 				ret = nct7904_read_reg(data, BANK_0,
392 						       SMI_STS7_REG +
393 						       ((channel - 5) >> 3));
394 				if (ret < 0)
395 					return ret;
396 				*val = (ret >> ((channel - 5) & 0x07)) & 1;
397 			} else {
398 				ret = nct7904_read_reg(data, BANK_0,
399 						       SMI_STS8_REG +
400 						       ((channel - 5) >> 3));
401 				if (ret < 0)
402 					return ret;
403 				*val = (ret >> (((channel - 5) & 0x07) - 4))
404 							& 1;
405 			}
406 		}
407 		return 0;
408 	case hwmon_temp_type:
409 		if (channel < 5) {
410 			if ((data->tcpu_mask >> channel) & 0x01) {
411 				if ((data->temp_mode >> channel) & 0x01)
412 					*val = 3; /* TD */
413 				else
414 					*val = 4; /* TR */
415 			} else {
416 				*val = 0;
417 			}
418 		} else {
419 			if ((data->has_dts >> (channel - 5)) & 0x01) {
420 				if (data->enable_dts & ENABLE_TSI)
421 					*val = 5; /* TSI */
422 				else
423 					*val = 6; /* PECI */
424 			} else {
425 				*val = 0;
426 			}
427 		}
428 		return 0;
429 	case hwmon_temp_max:
430 		reg1 = LTD_HV_LL_REG;
431 		reg2 = TEMP_CH1_W_REG;
432 		reg3 = DTS_T_CPU1_W_REG;
433 		break;
434 	case hwmon_temp_max_hyst:
435 		reg1 = LTD_LV_LL_REG;
436 		reg2 = TEMP_CH1_WH_REG;
437 		reg3 = DTS_T_CPU1_WH_REG;
438 		break;
439 	case hwmon_temp_crit:
440 		reg1 = LTD_HV_HL_REG;
441 		reg2 = TEMP_CH1_C_REG;
442 		reg3 = DTS_T_CPU1_C_REG;
443 		break;
444 	case hwmon_temp_crit_hyst:
445 		reg1 = LTD_LV_HL_REG;
446 		reg2 = TEMP_CH1_CH_REG;
447 		reg3 = DTS_T_CPU1_CH_REG;
448 		break;
449 	default:
450 		return -EOPNOTSUPP;
451 	}
452 
453 	if (channel == 4)
454 		ret = nct7904_read_reg(data, BANK_1, reg1);
455 	else if (channel < 5)
456 		ret = nct7904_read_reg(data, BANK_1,
457 				       reg2 + channel * 8);
458 	else
459 		ret = nct7904_read_reg(data, BANK_1,
460 				       reg3 + (channel - 5) * 4);
461 
462 	if (ret < 0)
463 		return ret;
464 	*val = ret * 1000;
465 	return 0;
466 }
467 
468 static umode_t nct7904_temp_is_visible(const void *_data, u32 attr, int channel)
469 {
470 	const struct nct7904_data *data = _data;
471 
472 	switch (attr) {
473 	case hwmon_temp_input:
474 	case hwmon_temp_alarm:
475 	case hwmon_temp_type:
476 		if (channel < 5) {
477 			if (data->tcpu_mask & BIT(channel))
478 				return 0444;
479 		} else {
480 			if (data->has_dts & BIT(channel - 5))
481 				return 0444;
482 		}
483 		break;
484 	case hwmon_temp_max:
485 	case hwmon_temp_max_hyst:
486 	case hwmon_temp_crit:
487 	case hwmon_temp_crit_hyst:
488 		if (channel < 5) {
489 			if (data->tcpu_mask & BIT(channel))
490 				return 0644;
491 		} else {
492 			if (data->has_dts & BIT(channel - 5))
493 				return 0644;
494 		}
495 		break;
496 	default:
497 		break;
498 	}
499 
500 	return 0;
501 }
502 
503 static int nct7904_read_pwm(struct device *dev, u32 attr, int channel,
504 			    long *val)
505 {
506 	struct nct7904_data *data = dev_get_drvdata(dev);
507 	int ret;
508 
509 	switch (attr) {
510 	case hwmon_pwm_input:
511 		ret = nct7904_read_reg(data, BANK_3, FANCTL1_OUT_REG + channel);
512 		if (ret < 0)
513 			return ret;
514 		*val = ret;
515 		return 0;
516 	case hwmon_pwm_enable:
517 		ret = nct7904_read_reg(data, BANK_3, FANCTL1_FMR_REG + channel);
518 		if (ret < 0)
519 			return ret;
520 
521 		*val = ret ? 2 : 1;
522 		return 0;
523 	default:
524 		return -EOPNOTSUPP;
525 	}
526 }
527 
528 static int nct7904_write_temp(struct device *dev, u32 attr, int channel,
529 			      long val)
530 {
531 	struct nct7904_data *data = dev_get_drvdata(dev);
532 	int ret;
533 	unsigned int reg1, reg2, reg3;
534 
535 	val = clamp_val(val / 1000, -128, 127);
536 
537 	switch (attr) {
538 	case hwmon_temp_max:
539 		reg1 = LTD_HV_LL_REG;
540 		reg2 = TEMP_CH1_W_REG;
541 		reg3 = DTS_T_CPU1_W_REG;
542 		break;
543 	case hwmon_temp_max_hyst:
544 		reg1 = LTD_LV_LL_REG;
545 		reg2 = TEMP_CH1_WH_REG;
546 		reg3 = DTS_T_CPU1_WH_REG;
547 		break;
548 	case hwmon_temp_crit:
549 		reg1 = LTD_HV_HL_REG;
550 		reg2 = TEMP_CH1_C_REG;
551 		reg3 = DTS_T_CPU1_C_REG;
552 		break;
553 	case hwmon_temp_crit_hyst:
554 		reg1 = LTD_LV_HL_REG;
555 		reg2 = TEMP_CH1_CH_REG;
556 		reg3 = DTS_T_CPU1_CH_REG;
557 		break;
558 	default:
559 		return -EOPNOTSUPP;
560 	}
561 	if (channel == 4)
562 		ret = nct7904_write_reg(data, BANK_1, reg1, val);
563 	else if (channel < 5)
564 		ret = nct7904_write_reg(data, BANK_1,
565 					reg2 + channel * 8, val);
566 	else
567 		ret = nct7904_write_reg(data, BANK_1,
568 					reg3 + (channel - 5) * 4, val);
569 
570 	return ret;
571 }
572 
573 static int nct7904_write_fan(struct device *dev, u32 attr, int channel,
574 			     long val)
575 {
576 	struct nct7904_data *data = dev_get_drvdata(dev);
577 	int ret;
578 	u8 tmp;
579 
580 	switch (attr) {
581 	case hwmon_fan_min:
582 		if (val <= 0)
583 			return -EINVAL;
584 
585 		val = clamp_val(DIV_ROUND_CLOSEST(1350000, val), 1, 0x1fff);
586 		tmp = (val >> 5) & 0xff;
587 		ret = nct7904_write_reg(data, BANK_1,
588 					FANIN1_HV_HL_REG + channel * 2, tmp);
589 		if (ret < 0)
590 			return ret;
591 		tmp = val & 0x1f;
592 		ret = nct7904_write_reg(data, BANK_1,
593 					FANIN1_LV_HL_REG + channel * 2, tmp);
594 		return ret;
595 	default:
596 		return -EOPNOTSUPP;
597 	}
598 }
599 
600 static int nct7904_write_in(struct device *dev, u32 attr, int channel,
601 			    long val)
602 {
603 	struct nct7904_data *data = dev_get_drvdata(dev);
604 	int ret, index, tmp;
605 
606 	index = nct7904_chan_to_index[channel];
607 
608 	if (index < 14)
609 		val = val / 2; /* 0.002V scale */
610 	else
611 		val = val / 6; /* 0.006V scale */
612 
613 	val = clamp_val(val, 0, 0x7ff);
614 
615 	switch (attr) {
616 	case hwmon_in_min:
617 		tmp = nct7904_read_reg(data, BANK_1,
618 				       VSEN1_LV_LL_REG + index * 4);
619 		if (tmp < 0)
620 			return tmp;
621 		tmp &= ~0x7;
622 		tmp |= val & 0x7;
623 		ret = nct7904_write_reg(data, BANK_1,
624 					VSEN1_LV_LL_REG + index * 4, tmp);
625 		if (ret < 0)
626 			return ret;
627 		tmp = nct7904_read_reg(data, BANK_1,
628 				       VSEN1_HV_LL_REG + index * 4);
629 		if (tmp < 0)
630 			return tmp;
631 		tmp = (val >> 3) & 0xff;
632 		ret = nct7904_write_reg(data, BANK_1,
633 					VSEN1_HV_LL_REG + index * 4, tmp);
634 		return ret;
635 	case hwmon_in_max:
636 		tmp = nct7904_read_reg(data, BANK_1,
637 				       VSEN1_LV_HL_REG + index * 4);
638 		if (tmp < 0)
639 			return tmp;
640 		tmp &= ~0x7;
641 		tmp |= val & 0x7;
642 		ret = nct7904_write_reg(data, BANK_1,
643 					VSEN1_LV_HL_REG + index * 4, tmp);
644 		if (ret < 0)
645 			return ret;
646 		tmp = nct7904_read_reg(data, BANK_1,
647 				       VSEN1_HV_HL_REG + index * 4);
648 		if (tmp < 0)
649 			return tmp;
650 		tmp = (val >> 3) & 0xff;
651 		ret = nct7904_write_reg(data, BANK_1,
652 					VSEN1_HV_HL_REG + index * 4, tmp);
653 		return ret;
654 	default:
655 		return -EOPNOTSUPP;
656 	}
657 }
658 
659 static int nct7904_write_pwm(struct device *dev, u32 attr, int channel,
660 			     long val)
661 {
662 	struct nct7904_data *data = dev_get_drvdata(dev);
663 	int ret;
664 
665 	switch (attr) {
666 	case hwmon_pwm_input:
667 		if (val < 0 || val > 255)
668 			return -EINVAL;
669 		ret = nct7904_write_reg(data, BANK_3, FANCTL1_OUT_REG + channel,
670 					val);
671 		return ret;
672 	case hwmon_pwm_enable:
673 		if (val < 1 || val > 2 ||
674 		    (val == 2 && !data->fan_mode[channel]))
675 			return -EINVAL;
676 		ret = nct7904_write_reg(data, BANK_3, FANCTL1_FMR_REG + channel,
677 					val == 2 ? data->fan_mode[channel] : 0);
678 		return ret;
679 	default:
680 		return -EOPNOTSUPP;
681 	}
682 }
683 
684 static umode_t nct7904_pwm_is_visible(const void *_data, u32 attr, int channel)
685 {
686 	switch (attr) {
687 	case hwmon_pwm_input:
688 	case hwmon_pwm_enable:
689 		return 0644;
690 	default:
691 		return 0;
692 	}
693 }
694 
695 static int nct7904_read(struct device *dev, enum hwmon_sensor_types type,
696 			u32 attr, int channel, long *val)
697 {
698 	switch (type) {
699 	case hwmon_in:
700 		return nct7904_read_in(dev, attr, channel, val);
701 	case hwmon_fan:
702 		return nct7904_read_fan(dev, attr, channel, val);
703 	case hwmon_pwm:
704 		return nct7904_read_pwm(dev, attr, channel, val);
705 	case hwmon_temp:
706 		return nct7904_read_temp(dev, attr, channel, val);
707 	default:
708 		return -EOPNOTSUPP;
709 	}
710 }
711 
712 static int nct7904_write(struct device *dev, enum hwmon_sensor_types type,
713 			 u32 attr, int channel, long val)
714 {
715 	switch (type) {
716 	case hwmon_in:
717 		return nct7904_write_in(dev, attr, channel, val);
718 	case hwmon_fan:
719 		return nct7904_write_fan(dev, attr, channel, val);
720 	case hwmon_pwm:
721 		return nct7904_write_pwm(dev, attr, channel, val);
722 	case hwmon_temp:
723 		return nct7904_write_temp(dev, attr, channel, val);
724 	default:
725 		return -EOPNOTSUPP;
726 	}
727 }
728 
729 static umode_t nct7904_is_visible(const void *data,
730 				  enum hwmon_sensor_types type,
731 				  u32 attr, int channel)
732 {
733 	switch (type) {
734 	case hwmon_in:
735 		return nct7904_in_is_visible(data, attr, channel);
736 	case hwmon_fan:
737 		return nct7904_fan_is_visible(data, attr, channel);
738 	case hwmon_pwm:
739 		return nct7904_pwm_is_visible(data, attr, channel);
740 	case hwmon_temp:
741 		return nct7904_temp_is_visible(data, attr, channel);
742 	default:
743 		return 0;
744 	}
745 }
746 
747 /* Return 0 if detection is successful, -ENODEV otherwise */
748 static int nct7904_detect(struct i2c_client *client,
749 			  struct i2c_board_info *info)
750 {
751 	struct i2c_adapter *adapter = client->adapter;
752 
753 	if (!i2c_check_functionality(adapter,
754 				     I2C_FUNC_SMBUS_READ_BYTE |
755 				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
756 		return -ENODEV;
757 
758 	/* Determine the chip type. */
759 	if (i2c_smbus_read_byte_data(client, VENDOR_ID_REG) != NUVOTON_ID ||
760 	    i2c_smbus_read_byte_data(client, CHIP_ID_REG) != NCT7904_ID ||
761 	    (i2c_smbus_read_byte_data(client, DEVICE_ID_REG) & 0xf0) != 0x50 ||
762 	    (i2c_smbus_read_byte_data(client, BANK_SEL_REG) & 0xf8) != 0x00)
763 		return -ENODEV;
764 
765 	strlcpy(info->type, "nct7904", I2C_NAME_SIZE);
766 
767 	return 0;
768 }
769 
770 static const struct hwmon_channel_info *nct7904_info[] = {
771 	HWMON_CHANNEL_INFO(in,
772 			   /* dummy, skipped in is_visible */
773 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
774 			   HWMON_I_ALARM,
775 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
776 			   HWMON_I_ALARM,
777 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
778 			   HWMON_I_ALARM,
779 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
780 			   HWMON_I_ALARM,
781 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
782 			   HWMON_I_ALARM,
783 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
784 			   HWMON_I_ALARM,
785 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
786 			   HWMON_I_ALARM,
787 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
788 			   HWMON_I_ALARM,
789 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
790 			   HWMON_I_ALARM,
791 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
792 			   HWMON_I_ALARM,
793 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
794 			   HWMON_I_ALARM,
795 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
796 			   HWMON_I_ALARM,
797 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
798 			   HWMON_I_ALARM,
799 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
800 			   HWMON_I_ALARM,
801 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
802 			   HWMON_I_ALARM,
803 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
804 			   HWMON_I_ALARM,
805 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
806 			   HWMON_I_ALARM,
807 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
808 			   HWMON_I_ALARM,
809 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
810 			   HWMON_I_ALARM,
811 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
812 			   HWMON_I_ALARM,
813 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
814 			   HWMON_I_ALARM),
815 	HWMON_CHANNEL_INFO(fan,
816 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
817 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
818 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
819 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
820 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
821 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
822 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
823 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM),
824 	HWMON_CHANNEL_INFO(pwm,
825 			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
826 			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
827 			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
828 			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
829 	HWMON_CHANNEL_INFO(temp,
830 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
831 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
832 			   HWMON_T_CRIT_HYST,
833 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
834 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
835 			   HWMON_T_CRIT_HYST,
836 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
837 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
838 			   HWMON_T_CRIT_HYST,
839 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
840 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
841 			   HWMON_T_CRIT_HYST,
842 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
843 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
844 			   HWMON_T_CRIT_HYST,
845 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
846 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
847 			   HWMON_T_CRIT_HYST,
848 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
849 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
850 			   HWMON_T_CRIT_HYST,
851 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
852 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
853 			   HWMON_T_CRIT_HYST,
854 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
855 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
856 			   HWMON_T_CRIT_HYST),
857 	NULL
858 };
859 
860 static const struct hwmon_ops nct7904_hwmon_ops = {
861 	.is_visible = nct7904_is_visible,
862 	.read = nct7904_read,
863 	.write = nct7904_write,
864 };
865 
866 static const struct hwmon_chip_info nct7904_chip_info = {
867 	.ops = &nct7904_hwmon_ops,
868 	.info = nct7904_info,
869 };
870 
871 static int nct7904_probe(struct i2c_client *client,
872 			 const struct i2c_device_id *id)
873 {
874 	struct nct7904_data *data;
875 	struct device *hwmon_dev;
876 	struct device *dev = &client->dev;
877 	int ret, i;
878 	u32 mask;
879 	u8 val, bit;
880 
881 	data = devm_kzalloc(dev, sizeof(struct nct7904_data), GFP_KERNEL);
882 	if (!data)
883 		return -ENOMEM;
884 
885 	data->client = client;
886 	mutex_init(&data->bank_lock);
887 	data->bank_sel = -1;
888 
889 	/* Setup sensor groups. */
890 	/* FANIN attributes */
891 	ret = nct7904_read_reg16(data, BANK_0, FANIN_CTRL0_REG);
892 	if (ret < 0)
893 		return ret;
894 	data->fanin_mask = (ret >> 8) | ((ret & 0xff) << 8);
895 
896 	/*
897 	 * VSEN attributes
898 	 *
899 	 * Note: voltage sensors overlap with external temperature
900 	 * sensors. So, if we ever decide to support the latter
901 	 * we will have to adjust 'vsen_mask' accordingly.
902 	 */
903 	mask = 0;
904 	ret = nct7904_read_reg16(data, BANK_0, VT_ADC_CTRL0_REG);
905 	if (ret >= 0)
906 		mask = (ret >> 8) | ((ret & 0xff) << 8);
907 	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL2_REG);
908 	if (ret >= 0)
909 		mask |= (ret << 16);
910 	data->vsen_mask = mask;
911 
912 	/* CPU_TEMP attributes */
913 	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL0_REG);
914 	if (ret < 0)
915 		return ret;
916 
917 	if ((ret & 0x6) == 0x6)
918 		data->tcpu_mask |= 1; /* TR1 */
919 	if ((ret & 0x18) == 0x18)
920 		data->tcpu_mask |= 2; /* TR2 */
921 	if ((ret & 0x20) == 0x20)
922 		data->tcpu_mask |= 4; /* TR3 */
923 	if ((ret & 0x80) == 0x80)
924 		data->tcpu_mask |= 8; /* TR4 */
925 
926 	/* LTD */
927 	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL2_REG);
928 	if (ret < 0)
929 		return ret;
930 	if ((ret & 0x02) == 0x02)
931 		data->tcpu_mask |= 0x10;
932 
933 	/* Multi-Function detecting for Volt and TR/TD */
934 	ret = nct7904_read_reg(data, BANK_0, VT_ADC_MD_REG);
935 	if (ret < 0)
936 		return ret;
937 
938 	data->temp_mode = 0;
939 	for (i = 0; i < 4; i++) {
940 		val = (ret >> (i * 2)) & 0x03;
941 		bit = (1 << i);
942 		if (val == VOLT_MONITOR_MODE) {
943 			data->tcpu_mask &= ~bit;
944 		} else if (val == THERMAL_DIODE_MODE && i < 2) {
945 			data->temp_mode |= bit;
946 			data->vsen_mask &= ~(0x06 << (i * 2));
947 		} else if (val == THERMISTOR_MODE) {
948 			data->vsen_mask &= ~(0x02 << (i * 2));
949 		} else {
950 			/* Reserved */
951 			data->tcpu_mask &= ~bit;
952 			data->vsen_mask &= ~(0x06 << (i * 2));
953 		}
954 	}
955 
956 	/* PECI */
957 	ret = nct7904_read_reg(data, BANK_2, PFE_REG);
958 	if (ret < 0)
959 		return ret;
960 	if (ret & 0x80) {
961 		data->enable_dts = 1; /* Enable DTS & PECI */
962 	} else {
963 		ret = nct7904_read_reg(data, BANK_2, TSI_CTRL_REG);
964 		if (ret < 0)
965 			return ret;
966 		if (ret & 0x80)
967 			data->enable_dts = 0x3; /* Enable DTS & TSI */
968 	}
969 
970 	/* Check DTS enable status */
971 	if (data->enable_dts) {
972 		ret = nct7904_read_reg(data, BANK_0, DTS_T_CTRL0_REG);
973 		if (ret < 0)
974 			return ret;
975 		data->has_dts = ret & 0xF;
976 		if (data->enable_dts & ENABLE_TSI) {
977 			ret = nct7904_read_reg(data, BANK_0, DTS_T_CTRL1_REG);
978 			if (ret < 0)
979 				return ret;
980 			data->has_dts |= (ret & 0xF) << 4;
981 		}
982 	}
983 
984 	for (i = 0; i < FANCTL_MAX; i++) {
985 		ret = nct7904_read_reg(data, BANK_3, FANCTL1_FMR_REG + i);
986 		if (ret < 0)
987 			return ret;
988 		data->fan_mode[i] = ret;
989 	}
990 
991 	hwmon_dev =
992 		devm_hwmon_device_register_with_info(dev, client->name, data,
993 						     &nct7904_chip_info, NULL);
994 	return PTR_ERR_OR_ZERO(hwmon_dev);
995 }
996 
997 static const struct i2c_device_id nct7904_id[] = {
998 	{"nct7904", 0},
999 	{}
1000 };
1001 MODULE_DEVICE_TABLE(i2c, nct7904_id);
1002 
1003 static struct i2c_driver nct7904_driver = {
1004 	.class = I2C_CLASS_HWMON,
1005 	.driver = {
1006 		.name = "nct7904",
1007 	},
1008 	.probe = nct7904_probe,
1009 	.id_table = nct7904_id,
1010 	.detect = nct7904_detect,
1011 	.address_list = normal_i2c,
1012 };
1013 
1014 module_i2c_driver(nct7904_driver);
1015 
1016 MODULE_AUTHOR("Vadim V. Vlasov <vvlasov@dev.rtsoft.ru>");
1017 MODULE_DESCRIPTION("Hwmon driver for NUVOTON NCT7904");
1018 MODULE_LICENSE("GPL");
1019