xref: /openbmc/linux/drivers/hwmon/lm90.c (revision de6da33e)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * lm90.c - Part of lm_sensors, Linux kernel modules for hardware
4  *          monitoring
5  * Copyright (C) 2003-2010  Jean Delvare <jdelvare@suse.de>
6  *
7  * Based on the lm83 driver. The LM90 is a sensor chip made by National
8  * Semiconductor. It reports up to two temperatures (its own plus up to
9  * one external one) with a 0.125 deg resolution (1 deg for local
10  * temperature) and a 3-4 deg accuracy.
11  *
12  * This driver also supports the LM89 and LM99, two other sensor chips
13  * made by National Semiconductor. Both have an increased remote
14  * temperature measurement accuracy (1 degree), and the LM99
15  * additionally shifts remote temperatures (measured and limits) by 16
16  * degrees, which allows for higher temperatures measurement.
17  * Note that there is no way to differentiate between both chips.
18  * When device is auto-detected, the driver will assume an LM99.
19  *
20  * This driver also supports the LM86, another sensor chip made by
21  * National Semiconductor. It is exactly similar to the LM90 except it
22  * has a higher accuracy.
23  *
24  * This driver also supports the ADM1032, a sensor chip made by Analog
25  * Devices. That chip is similar to the LM90, with a few differences
26  * that are not handled by this driver. Among others, it has a higher
27  * accuracy than the LM90, much like the LM86 does.
28  *
29  * This driver also supports the MAX6657, MAX6658 and MAX6659 sensor
30  * chips made by Maxim. These chips are similar to the LM86.
31  * Note that there is no easy way to differentiate between the three
32  * variants. We use the device address to detect MAX6659, which will result
33  * in a detection as max6657 if it is on address 0x4c. The extra address
34  * and features of the MAX6659 are only supported if the chip is configured
35  * explicitly as max6659, or if its address is not 0x4c.
36  * These chips lack the remote temperature offset feature.
37  *
38  * This driver also supports the MAX6654 chip made by Maxim. This chip can
39  * be at 9 different addresses, similar to MAX6680/MAX6681. The MAX6654 is
40  * otherwise similar to MAX6657/MAX6658/MAX6659. Extended range is available
41  * by setting the configuration register accordingly, and is done during
42  * initialization. Extended precision is only available at conversion rates
43  * of 1 Hz and slower. Note that extended precision is not enabled by
44  * default, as this driver initializes all chips to 2 Hz by design.
45  *
46  * This driver also supports the MAX6646, MAX6647, MAX6648, MAX6649 and
47  * MAX6692 chips made by Maxim.  These are again similar to the LM86,
48  * but they use unsigned temperature values and can report temperatures
49  * from 0 to 145 degrees.
50  *
51  * This driver also supports the MAX6680 and MAX6681, two other sensor
52  * chips made by Maxim. These are quite similar to the other Maxim
53  * chips. The MAX6680 and MAX6681 only differ in the pinout so they can
54  * be treated identically.
55  *
56  * This driver also supports the MAX6695 and MAX6696, two other sensor
57  * chips made by Maxim. These are also quite similar to other Maxim
58  * chips, but support three temperature sensors instead of two. MAX6695
59  * and MAX6696 only differ in the pinout so they can be treated identically.
60  *
61  * This driver also supports ADT7461 and ADT7461A from Analog Devices as well as
62  * NCT1008 from ON Semiconductor. The chips are supported in both compatibility
63  * and extended mode. They are mostly compatible with LM90 except for a data
64  * format difference for the temperature value registers.
65  *
66  * This driver also supports the SA56004 from Philips. This device is
67  * pin-compatible with the LM86, the ED/EDP parts are also address-compatible.
68  *
69  * This driver also supports the G781 from GMT. This device is compatible
70  * with the ADM1032.
71  *
72  * This driver also supports TMP451 and TMP461 from Texas Instruments.
73  * Those devices are supported in both compatibility and extended mode.
74  * They are mostly compatible with ADT7461 except for local temperature
75  * low byte register and max conversion rate.
76  *
77  * Since the LM90 was the first chipset supported by this driver, most
78  * comments will refer to this chipset, but are actually general and
79  * concern all supported chipsets, unless mentioned otherwise.
80  */
81 
82 #include <linux/module.h>
83 #include <linux/init.h>
84 #include <linux/slab.h>
85 #include <linux/jiffies.h>
86 #include <linux/i2c.h>
87 #include <linux/hwmon.h>
88 #include <linux/err.h>
89 #include <linux/mutex.h>
90 #include <linux/of_device.h>
91 #include <linux/sysfs.h>
92 #include <linux/interrupt.h>
93 #include <linux/regulator/consumer.h>
94 
95 /*
96  * Addresses to scan
97  * Address is fully defined internally and cannot be changed except for
98  * MAX6659, MAX6680 and MAX6681.
99  * LM86, LM89, LM90, LM99, ADM1032, ADM1032-1, ADT7461, ADT7461A, MAX6649,
100  * MAX6657, MAX6658, NCT1008 and W83L771 have address 0x4c.
101  * ADM1032-2, ADT7461-2, ADT7461A-2, LM89-1, LM99-1, MAX6646, and NCT1008D
102  * have address 0x4d.
103  * MAX6647 has address 0x4e.
104  * MAX6659 can have address 0x4c, 0x4d or 0x4e.
105  * MAX6654, MAX6680, and MAX6681 can have address 0x18, 0x19, 0x1a, 0x29,
106  * 0x2a, 0x2b, 0x4c, 0x4d or 0x4e.
107  * SA56004 can have address 0x48 through 0x4F.
108  */
109 
110 static const unsigned short normal_i2c[] = {
111 	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x48, 0x49, 0x4a, 0x4b, 0x4c,
112 	0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
113 
114 enum chips { lm90, adm1032, lm99, lm86, max6657, max6659, adt7461, max6680,
115 	max6646, w83l771, max6696, sa56004, g781, tmp451, tmp461, max6654 };
116 
117 /*
118  * The LM90 registers
119  */
120 
121 #define LM90_REG_R_MAN_ID		0xFE
122 #define LM90_REG_R_CHIP_ID		0xFF
123 #define LM90_REG_R_CONFIG1		0x03
124 #define LM90_REG_W_CONFIG1		0x09
125 #define LM90_REG_R_CONFIG2		0xBF
126 #define LM90_REG_W_CONFIG2		0xBF
127 #define LM90_REG_R_CONVRATE		0x04
128 #define LM90_REG_W_CONVRATE		0x0A
129 #define LM90_REG_R_STATUS		0x02
130 #define LM90_REG_R_LOCAL_TEMP		0x00
131 #define LM90_REG_R_LOCAL_HIGH		0x05
132 #define LM90_REG_W_LOCAL_HIGH		0x0B
133 #define LM90_REG_R_LOCAL_LOW		0x06
134 #define LM90_REG_W_LOCAL_LOW		0x0C
135 #define LM90_REG_R_LOCAL_CRIT		0x20
136 #define LM90_REG_W_LOCAL_CRIT		0x20
137 #define LM90_REG_R_REMOTE_TEMPH		0x01
138 #define LM90_REG_R_REMOTE_TEMPL		0x10
139 #define LM90_REG_R_REMOTE_OFFSH		0x11
140 #define LM90_REG_W_REMOTE_OFFSH		0x11
141 #define LM90_REG_R_REMOTE_OFFSL		0x12
142 #define LM90_REG_W_REMOTE_OFFSL		0x12
143 #define LM90_REG_R_REMOTE_HIGHH		0x07
144 #define LM90_REG_W_REMOTE_HIGHH		0x0D
145 #define LM90_REG_R_REMOTE_HIGHL		0x13
146 #define LM90_REG_W_REMOTE_HIGHL		0x13
147 #define LM90_REG_R_REMOTE_LOWH		0x08
148 #define LM90_REG_W_REMOTE_LOWH		0x0E
149 #define LM90_REG_R_REMOTE_LOWL		0x14
150 #define LM90_REG_W_REMOTE_LOWL		0x14
151 #define LM90_REG_R_REMOTE_CRIT		0x19
152 #define LM90_REG_W_REMOTE_CRIT		0x19
153 #define LM90_REG_R_TCRIT_HYST		0x21
154 #define LM90_REG_W_TCRIT_HYST		0x21
155 
156 /* MAX6646/6647/6649/6654/6657/6658/6659/6695/6696 registers */
157 
158 #define MAX6657_REG_R_LOCAL_TEMPL	0x11
159 #define MAX6696_REG_R_STATUS2		0x12
160 #define MAX6659_REG_R_REMOTE_EMERG	0x16
161 #define MAX6659_REG_W_REMOTE_EMERG	0x16
162 #define MAX6659_REG_R_LOCAL_EMERG	0x17
163 #define MAX6659_REG_W_LOCAL_EMERG	0x17
164 
165 /*  SA56004 registers */
166 
167 #define SA56004_REG_R_LOCAL_TEMPL 0x22
168 
169 #define LM90_MAX_CONVRATE_MS	16000	/* Maximum conversion rate in ms */
170 
171 /* TMP451/TMP461 registers */
172 #define TMP451_REG_R_LOCAL_TEMPL	0x15
173 #define TMP451_REG_CONALERT		0x22
174 
175 #define TMP461_REG_CHEN			0x16
176 #define TMP461_REG_DFC			0x24
177 
178 /*
179  * Device flags
180  */
181 #define LM90_FLAG_ADT7461_EXT	(1 << 0) /* ADT7461 extended mode	*/
182 /* Device features */
183 #define LM90_HAVE_OFFSET	(1 << 1) /* temperature offset register	*/
184 #define LM90_HAVE_REM_LIMIT_EXT	(1 << 3) /* extended remote limit	*/
185 #define LM90_HAVE_EMERGENCY	(1 << 4) /* 3rd upper (emergency) limit	*/
186 #define LM90_HAVE_EMERGENCY_ALARM (1 << 5)/* emergency alarm		*/
187 #define LM90_HAVE_TEMP3		(1 << 6) /* 3rd temperature sensor	*/
188 #define LM90_HAVE_BROKEN_ALERT	(1 << 7) /* Broken alert		*/
189 #define LM90_HAVE_EXTENDED_TEMP	(1 << 8) /* extended temperature support*/
190 #define LM90_PAUSE_FOR_CONFIG	(1 << 9) /* Pause conversion for config	*/
191 
192 /* LM90 status */
193 #define LM90_STATUS_LTHRM	(1 << 0) /* local THERM limit tripped */
194 #define LM90_STATUS_RTHRM	(1 << 1) /* remote THERM limit tripped */
195 #define LM90_STATUS_ROPEN	(1 << 2) /* remote is an open circuit */
196 #define LM90_STATUS_RLOW	(1 << 3) /* remote low temp limit tripped */
197 #define LM90_STATUS_RHIGH	(1 << 4) /* remote high temp limit tripped */
198 #define LM90_STATUS_LLOW	(1 << 5) /* local low temp limit tripped */
199 #define LM90_STATUS_LHIGH	(1 << 6) /* local high temp limit tripped */
200 
201 #define MAX6696_STATUS2_R2THRM	(1 << 1) /* remote2 THERM limit tripped */
202 #define MAX6696_STATUS2_R2OPEN	(1 << 2) /* remote2 is an open circuit */
203 #define MAX6696_STATUS2_R2LOW	(1 << 3) /* remote2 low temp limit tripped */
204 #define MAX6696_STATUS2_R2HIGH	(1 << 4) /* remote2 high temp limit tripped */
205 #define MAX6696_STATUS2_ROT2	(1 << 5) /* remote emergency limit tripped */
206 #define MAX6696_STATUS2_R2OT2	(1 << 6) /* remote2 emergency limit tripped */
207 #define MAX6696_STATUS2_LOT2	(1 << 7) /* local emergency limit tripped */
208 
209 /*
210  * Driver data (common to all clients)
211  */
212 
213 static const struct i2c_device_id lm90_id[] = {
214 	{ "adm1032", adm1032 },
215 	{ "adt7461", adt7461 },
216 	{ "adt7461a", adt7461 },
217 	{ "g781", g781 },
218 	{ "lm90", lm90 },
219 	{ "lm86", lm86 },
220 	{ "lm89", lm86 },
221 	{ "lm99", lm99 },
222 	{ "max6646", max6646 },
223 	{ "max6647", max6646 },
224 	{ "max6649", max6646 },
225 	{ "max6654", max6654 },
226 	{ "max6657", max6657 },
227 	{ "max6658", max6657 },
228 	{ "max6659", max6659 },
229 	{ "max6680", max6680 },
230 	{ "max6681", max6680 },
231 	{ "max6695", max6696 },
232 	{ "max6696", max6696 },
233 	{ "nct1008", adt7461 },
234 	{ "w83l771", w83l771 },
235 	{ "sa56004", sa56004 },
236 	{ "tmp451", tmp451 },
237 	{ "tmp461", tmp461 },
238 	{ }
239 };
240 MODULE_DEVICE_TABLE(i2c, lm90_id);
241 
242 static const struct of_device_id __maybe_unused lm90_of_match[] = {
243 	{
244 		.compatible = "adi,adm1032",
245 		.data = (void *)adm1032
246 	},
247 	{
248 		.compatible = "adi,adt7461",
249 		.data = (void *)adt7461
250 	},
251 	{
252 		.compatible = "adi,adt7461a",
253 		.data = (void *)adt7461
254 	},
255 	{
256 		.compatible = "gmt,g781",
257 		.data = (void *)g781
258 	},
259 	{
260 		.compatible = "national,lm90",
261 		.data = (void *)lm90
262 	},
263 	{
264 		.compatible = "national,lm86",
265 		.data = (void *)lm86
266 	},
267 	{
268 		.compatible = "national,lm89",
269 		.data = (void *)lm86
270 	},
271 	{
272 		.compatible = "national,lm99",
273 		.data = (void *)lm99
274 	},
275 	{
276 		.compatible = "dallas,max6646",
277 		.data = (void *)max6646
278 	},
279 	{
280 		.compatible = "dallas,max6647",
281 		.data = (void *)max6646
282 	},
283 	{
284 		.compatible = "dallas,max6649",
285 		.data = (void *)max6646
286 	},
287 	{
288 		.compatible = "dallas,max6654",
289 		.data = (void *)max6654
290 	},
291 	{
292 		.compatible = "dallas,max6657",
293 		.data = (void *)max6657
294 	},
295 	{
296 		.compatible = "dallas,max6658",
297 		.data = (void *)max6657
298 	},
299 	{
300 		.compatible = "dallas,max6659",
301 		.data = (void *)max6659
302 	},
303 	{
304 		.compatible = "dallas,max6680",
305 		.data = (void *)max6680
306 	},
307 	{
308 		.compatible = "dallas,max6681",
309 		.data = (void *)max6680
310 	},
311 	{
312 		.compatible = "dallas,max6695",
313 		.data = (void *)max6696
314 	},
315 	{
316 		.compatible = "dallas,max6696",
317 		.data = (void *)max6696
318 	},
319 	{
320 		.compatible = "onnn,nct1008",
321 		.data = (void *)adt7461
322 	},
323 	{
324 		.compatible = "winbond,w83l771",
325 		.data = (void *)w83l771
326 	},
327 	{
328 		.compatible = "nxp,sa56004",
329 		.data = (void *)sa56004
330 	},
331 	{
332 		.compatible = "ti,tmp451",
333 		.data = (void *)tmp451
334 	},
335 	{
336 		.compatible = "ti,tmp461",
337 		.data = (void *)tmp461
338 	},
339 	{ },
340 };
341 MODULE_DEVICE_TABLE(of, lm90_of_match);
342 
343 /*
344  * chip type specific parameters
345  */
346 struct lm90_params {
347 	u32 flags;		/* Capabilities */
348 	u16 alert_alarms;	/* Which alarm bits trigger ALERT# */
349 				/* Upper 8 bits for max6695/96 */
350 	u8 max_convrate;	/* Maximum conversion rate register value */
351 	u8 reg_local_ext;	/* Extended local temp register (optional) */
352 };
353 
354 static const struct lm90_params lm90_params[] = {
355 	[adm1032] = {
356 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
357 		  | LM90_HAVE_BROKEN_ALERT,
358 		.alert_alarms = 0x7c,
359 		.max_convrate = 10,
360 	},
361 	[adt7461] = {
362 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
363 		  | LM90_HAVE_BROKEN_ALERT | LM90_HAVE_EXTENDED_TEMP,
364 		.alert_alarms = 0x7c,
365 		.max_convrate = 10,
366 	},
367 	[g781] = {
368 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
369 		  | LM90_HAVE_BROKEN_ALERT,
370 		.alert_alarms = 0x7c,
371 		.max_convrate = 8,
372 	},
373 	[lm86] = {
374 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT,
375 		.alert_alarms = 0x7b,
376 		.max_convrate = 9,
377 	},
378 	[lm90] = {
379 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT,
380 		.alert_alarms = 0x7b,
381 		.max_convrate = 9,
382 	},
383 	[lm99] = {
384 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT,
385 		.alert_alarms = 0x7b,
386 		.max_convrate = 9,
387 	},
388 	[max6646] = {
389 		.alert_alarms = 0x7c,
390 		.max_convrate = 6,
391 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
392 	},
393 	[max6654] = {
394 		.alert_alarms = 0x7c,
395 		.max_convrate = 7,
396 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
397 	},
398 	[max6657] = {
399 		.flags = LM90_PAUSE_FOR_CONFIG,
400 		.alert_alarms = 0x7c,
401 		.max_convrate = 8,
402 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
403 	},
404 	[max6659] = {
405 		.flags = LM90_HAVE_EMERGENCY,
406 		.alert_alarms = 0x7c,
407 		.max_convrate = 8,
408 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
409 	},
410 	[max6680] = {
411 		.flags = LM90_HAVE_OFFSET,
412 		.alert_alarms = 0x7c,
413 		.max_convrate = 7,
414 	},
415 	[max6696] = {
416 		.flags = LM90_HAVE_EMERGENCY
417 		  | LM90_HAVE_EMERGENCY_ALARM | LM90_HAVE_TEMP3,
418 		.alert_alarms = 0x1c7c,
419 		.max_convrate = 6,
420 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
421 	},
422 	[w83l771] = {
423 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT,
424 		.alert_alarms = 0x7c,
425 		.max_convrate = 8,
426 	},
427 	[sa56004] = {
428 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT,
429 		.alert_alarms = 0x7b,
430 		.max_convrate = 9,
431 		.reg_local_ext = SA56004_REG_R_LOCAL_TEMPL,
432 	},
433 	[tmp451] = {
434 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
435 		  | LM90_HAVE_BROKEN_ALERT | LM90_HAVE_EXTENDED_TEMP,
436 		.alert_alarms = 0x7c,
437 		.max_convrate = 9,
438 		.reg_local_ext = TMP451_REG_R_LOCAL_TEMPL,
439 	},
440 	[tmp461] = {
441 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
442 		  | LM90_HAVE_BROKEN_ALERT | LM90_HAVE_EXTENDED_TEMP,
443 		.alert_alarms = 0x7c,
444 		.max_convrate = 9,
445 		.reg_local_ext = TMP451_REG_R_LOCAL_TEMPL,
446 	},
447 };
448 
449 /*
450  * TEMP8 register index
451  */
452 enum lm90_temp8_reg_index {
453 	LOCAL_LOW = 0,
454 	LOCAL_HIGH,
455 	LOCAL_CRIT,
456 	REMOTE_CRIT,
457 	LOCAL_EMERG,	/* max6659 and max6695/96 */
458 	REMOTE_EMERG,	/* max6659 and max6695/96 */
459 	REMOTE2_CRIT,	/* max6695/96 only */
460 	REMOTE2_EMERG,	/* max6695/96 only */
461 	TEMP8_REG_NUM
462 };
463 
464 /*
465  * TEMP11 register index
466  */
467 enum lm90_temp11_reg_index {
468 	REMOTE_TEMP = 0,
469 	REMOTE_LOW,
470 	REMOTE_HIGH,
471 	REMOTE_OFFSET,	/* except max6646, max6657/58/59, and max6695/96 */
472 	LOCAL_TEMP,
473 	REMOTE2_TEMP,	/* max6695/96 only */
474 	REMOTE2_LOW,	/* max6695/96 only */
475 	REMOTE2_HIGH,	/* max6695/96 only */
476 	TEMP11_REG_NUM
477 };
478 
479 /*
480  * Client data (each client gets its own)
481  */
482 
483 struct lm90_data {
484 	struct i2c_client *client;
485 	struct device *hwmon_dev;
486 	u32 channel_config[4];
487 	struct hwmon_channel_info temp_info;
488 	const struct hwmon_channel_info *info[3];
489 	struct hwmon_chip_info chip;
490 	struct mutex update_lock;
491 	bool valid;		/* true if register values are valid */
492 	unsigned long last_updated; /* in jiffies */
493 	int kind;
494 	u32 flags;
495 
496 	unsigned int update_interval; /* in milliseconds */
497 
498 	u8 config;		/* Current configuration register value */
499 	u8 config_orig;		/* Original configuration register value */
500 	u8 convrate_orig;	/* Original conversion rate register value */
501 	u16 alert_alarms;	/* Which alarm bits trigger ALERT# */
502 				/* Upper 8 bits for max6695/96 */
503 	u8 max_convrate;	/* Maximum conversion rate */
504 	u8 reg_local_ext;	/* local extension register offset */
505 
506 	/* registers values */
507 	s8 temp8[TEMP8_REG_NUM];
508 	s16 temp11[TEMP11_REG_NUM];
509 	u8 temp_hyst;
510 	u16 alarms; /* bitvector (upper 8 bits for max6695/96) */
511 };
512 
513 /*
514  * Support functions
515  */
516 
517 /*
518  * The ADM1032 supports PEC but not on write byte transactions, so we need
519  * to explicitly ask for a transaction without PEC.
520  */
521 static inline s32 adm1032_write_byte(struct i2c_client *client, u8 value)
522 {
523 	return i2c_smbus_xfer(client->adapter, client->addr,
524 			      client->flags & ~I2C_CLIENT_PEC,
525 			      I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL);
526 }
527 
528 /*
529  * It is assumed that client->update_lock is held (unless we are in
530  * detection or initialization steps). This matters when PEC is enabled,
531  * because we don't want the address pointer to change between the write
532  * byte and the read byte transactions.
533  */
534 static int lm90_read_reg(struct i2c_client *client, u8 reg)
535 {
536 	int err;
537 
538 	if (client->flags & I2C_CLIENT_PEC) {
539 		err = adm1032_write_byte(client, reg);
540 		if (err >= 0)
541 			err = i2c_smbus_read_byte(client);
542 	} else
543 		err = i2c_smbus_read_byte_data(client, reg);
544 
545 	return err;
546 }
547 
548 static int lm90_read16(struct i2c_client *client, u8 regh, u8 regl)
549 {
550 	int oldh, newh, l;
551 
552 	/*
553 	 * There is a trick here. We have to read two registers to have the
554 	 * sensor temperature, but we have to beware a conversion could occur
555 	 * between the readings. The datasheet says we should either use
556 	 * the one-shot conversion register, which we don't want to do
557 	 * (disables hardware monitoring) or monitor the busy bit, which is
558 	 * impossible (we can't read the values and monitor that bit at the
559 	 * exact same time). So the solution used here is to read the high
560 	 * byte once, then the low byte, then the high byte again. If the new
561 	 * high byte matches the old one, then we have a valid reading. Else
562 	 * we have to read the low byte again, and now we believe we have a
563 	 * correct reading.
564 	 */
565 	oldh = lm90_read_reg(client, regh);
566 	if (oldh < 0)
567 		return oldh;
568 	l = lm90_read_reg(client, regl);
569 	if (l < 0)
570 		return l;
571 	newh = lm90_read_reg(client, regh);
572 	if (newh < 0)
573 		return newh;
574 	if (oldh != newh) {
575 		l = lm90_read_reg(client, regl);
576 		if (l < 0)
577 			return l;
578 	}
579 	return (newh << 8) | l;
580 }
581 
582 static int lm90_update_confreg(struct lm90_data *data, u8 config)
583 {
584 	if (data->config != config) {
585 		int err;
586 
587 		err = i2c_smbus_write_byte_data(data->client,
588 						LM90_REG_W_CONFIG1,
589 						config);
590 		if (err)
591 			return err;
592 		data->config = config;
593 	}
594 	return 0;
595 }
596 
597 /*
598  * client->update_lock must be held when calling this function (unless we are
599  * in detection or initialization steps), and while a remote channel other
600  * than channel 0 is selected. Also, calling code must make sure to re-select
601  * external channel 0 before releasing the lock. This is necessary because
602  * various registers have different meanings as a result of selecting a
603  * non-default remote channel.
604  */
605 static int lm90_select_remote_channel(struct lm90_data *data, int channel)
606 {
607 	int err = 0;
608 
609 	if (data->kind == max6696) {
610 		u8 config = data->config & ~0x08;
611 
612 		if (channel)
613 			config |= 0x08;
614 		err = lm90_update_confreg(data, config);
615 	}
616 	return err;
617 }
618 
619 static int lm90_write_convrate(struct lm90_data *data, int val)
620 {
621 	u8 config = data->config;
622 	int err;
623 
624 	/* Save config and pause conversion */
625 	if (data->flags & LM90_PAUSE_FOR_CONFIG) {
626 		err = lm90_update_confreg(data, config | 0x40);
627 		if (err < 0)
628 			return err;
629 	}
630 
631 	/* Set conv rate */
632 	err = i2c_smbus_write_byte_data(data->client, LM90_REG_W_CONVRATE, val);
633 
634 	/* Revert change to config */
635 	lm90_update_confreg(data, config);
636 
637 	return err;
638 }
639 
640 /*
641  * Set conversion rate.
642  * client->update_lock must be held when calling this function (unless we are
643  * in detection or initialization steps).
644  */
645 static int lm90_set_convrate(struct i2c_client *client, struct lm90_data *data,
646 			     unsigned int interval)
647 {
648 	unsigned int update_interval;
649 	int i, err;
650 
651 	/* Shift calculations to avoid rounding errors */
652 	interval <<= 6;
653 
654 	/* find the nearest update rate */
655 	for (i = 0, update_interval = LM90_MAX_CONVRATE_MS << 6;
656 	     i < data->max_convrate; i++, update_interval >>= 1)
657 		if (interval >= update_interval * 3 / 4)
658 			break;
659 
660 	err = lm90_write_convrate(data, i);
661 	data->update_interval = DIV_ROUND_CLOSEST(update_interval, 64);
662 	return err;
663 }
664 
665 static int lm90_update_limits(struct device *dev)
666 {
667 	struct lm90_data *data = dev_get_drvdata(dev);
668 	struct i2c_client *client = data->client;
669 	int val;
670 
671 	val = lm90_read_reg(client, LM90_REG_R_LOCAL_CRIT);
672 	if (val < 0)
673 		return val;
674 	data->temp8[LOCAL_CRIT] = val;
675 
676 	val = lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT);
677 	if (val < 0)
678 		return val;
679 	data->temp8[REMOTE_CRIT] = val;
680 
681 	val = lm90_read_reg(client, LM90_REG_R_TCRIT_HYST);
682 	if (val < 0)
683 		return val;
684 	data->temp_hyst = val;
685 
686 	val = lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH);
687 	if (val < 0)
688 		return val;
689 	data->temp11[REMOTE_LOW] = val << 8;
690 
691 	if (data->flags & LM90_HAVE_REM_LIMIT_EXT) {
692 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_LOWL);
693 		if (val < 0)
694 			return val;
695 		data->temp11[REMOTE_LOW] |= val;
696 	}
697 
698 	val = lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH);
699 	if (val < 0)
700 		return val;
701 	data->temp11[REMOTE_HIGH] = val << 8;
702 
703 	if (data->flags & LM90_HAVE_REM_LIMIT_EXT) {
704 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHL);
705 		if (val < 0)
706 			return val;
707 		data->temp11[REMOTE_HIGH] |= val;
708 	}
709 
710 	if (data->flags & LM90_HAVE_OFFSET) {
711 		val = lm90_read16(client, LM90_REG_R_REMOTE_OFFSH,
712 				  LM90_REG_R_REMOTE_OFFSL);
713 		if (val < 0)
714 			return val;
715 		data->temp11[REMOTE_OFFSET] = val;
716 	}
717 
718 	if (data->flags & LM90_HAVE_EMERGENCY) {
719 		val = lm90_read_reg(client, MAX6659_REG_R_LOCAL_EMERG);
720 		if (val < 0)
721 			return val;
722 		data->temp8[LOCAL_EMERG] = val;
723 
724 		val = lm90_read_reg(client, MAX6659_REG_R_REMOTE_EMERG);
725 		if (val < 0)
726 			return val;
727 		data->temp8[REMOTE_EMERG] = val;
728 	}
729 
730 	if (data->kind == max6696) {
731 		val = lm90_select_remote_channel(data, 1);
732 		if (val < 0)
733 			return val;
734 
735 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT);
736 		if (val < 0)
737 			return val;
738 		data->temp8[REMOTE2_CRIT] = val;
739 
740 		val = lm90_read_reg(client, MAX6659_REG_R_REMOTE_EMERG);
741 		if (val < 0)
742 			return val;
743 		data->temp8[REMOTE2_EMERG] = val;
744 
745 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH);
746 		if (val < 0)
747 			return val;
748 		data->temp11[REMOTE2_LOW] = val << 8;
749 
750 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH);
751 		if (val < 0)
752 			return val;
753 		data->temp11[REMOTE2_HIGH] = val << 8;
754 
755 		lm90_select_remote_channel(data, 0);
756 	}
757 
758 	return 0;
759 }
760 
761 static int lm90_update_device(struct device *dev)
762 {
763 	struct lm90_data *data = dev_get_drvdata(dev);
764 	struct i2c_client *client = data->client;
765 	unsigned long next_update;
766 	int val;
767 
768 	if (!data->valid) {
769 		val = lm90_update_limits(dev);
770 		if (val < 0)
771 			return val;
772 	}
773 
774 	next_update = data->last_updated +
775 		      msecs_to_jiffies(data->update_interval);
776 	if (time_after(jiffies, next_update) || !data->valid) {
777 		dev_dbg(&client->dev, "Updating lm90 data.\n");
778 
779 		data->valid = false;
780 
781 		val = lm90_read_reg(client, LM90_REG_R_LOCAL_LOW);
782 		if (val < 0)
783 			return val;
784 		data->temp8[LOCAL_LOW] = val;
785 
786 		val = lm90_read_reg(client, LM90_REG_R_LOCAL_HIGH);
787 		if (val < 0)
788 			return val;
789 		data->temp8[LOCAL_HIGH] = val;
790 
791 		if (data->reg_local_ext) {
792 			val = lm90_read16(client, LM90_REG_R_LOCAL_TEMP,
793 					  data->reg_local_ext);
794 			if (val < 0)
795 				return val;
796 			data->temp11[LOCAL_TEMP] = val;
797 		} else {
798 			val = lm90_read_reg(client, LM90_REG_R_LOCAL_TEMP);
799 			if (val < 0)
800 				return val;
801 			data->temp11[LOCAL_TEMP] = val << 8;
802 		}
803 		val = lm90_read16(client, LM90_REG_R_REMOTE_TEMPH,
804 				  LM90_REG_R_REMOTE_TEMPL);
805 		if (val < 0)
806 			return val;
807 		data->temp11[REMOTE_TEMP] = val;
808 
809 		val = lm90_read_reg(client, LM90_REG_R_STATUS);
810 		if (val < 0)
811 			return val;
812 		data->alarms = val;	/* lower 8 bit of alarms */
813 
814 		if (data->kind == max6696) {
815 			val = lm90_select_remote_channel(data, 1);
816 			if (val < 0)
817 				return val;
818 
819 			val = lm90_read16(client, LM90_REG_R_REMOTE_TEMPH,
820 					  LM90_REG_R_REMOTE_TEMPL);
821 			if (val < 0) {
822 				lm90_select_remote_channel(data, 0);
823 				return val;
824 			}
825 			data->temp11[REMOTE2_TEMP] = val;
826 
827 			lm90_select_remote_channel(data, 0);
828 
829 			val = lm90_read_reg(client, MAX6696_REG_R_STATUS2);
830 			if (val < 0)
831 				return val;
832 			data->alarms |= val << 8;
833 		}
834 
835 		/*
836 		 * Re-enable ALERT# output if it was originally enabled and
837 		 * relevant alarms are all clear
838 		 */
839 		if (!(data->config_orig & 0x80) &&
840 		    !(data->alarms & data->alert_alarms)) {
841 			if (data->config & 0x80) {
842 				dev_dbg(&client->dev, "Re-enabling ALERT#\n");
843 				lm90_update_confreg(data, data->config & ~0x80);
844 			}
845 		}
846 
847 		data->last_updated = jiffies;
848 		data->valid = true;
849 	}
850 
851 	return 0;
852 }
853 
854 /*
855  * Conversions
856  * For local temperatures and limits, critical limits and the hysteresis
857  * value, the LM90 uses signed 8-bit values with LSB = 1 degree Celsius.
858  * For remote temperatures and limits, it uses signed 11-bit values with
859  * LSB = 0.125 degree Celsius, left-justified in 16-bit registers.  Some
860  * Maxim chips use unsigned values.
861  */
862 
863 static inline int temp_from_s8(s8 val)
864 {
865 	return val * 1000;
866 }
867 
868 static inline int temp_from_u8(u8 val)
869 {
870 	return val * 1000;
871 }
872 
873 static inline int temp_from_s16(s16 val)
874 {
875 	return val / 32 * 125;
876 }
877 
878 static inline int temp_from_u16(u16 val)
879 {
880 	return val / 32 * 125;
881 }
882 
883 static s8 temp_to_s8(long val)
884 {
885 	if (val <= -128000)
886 		return -128;
887 	if (val >= 127000)
888 		return 127;
889 	if (val < 0)
890 		return (val - 500) / 1000;
891 	return (val + 500) / 1000;
892 }
893 
894 static u8 temp_to_u8(long val)
895 {
896 	if (val <= 0)
897 		return 0;
898 	if (val >= 255000)
899 		return 255;
900 	return (val + 500) / 1000;
901 }
902 
903 static s16 temp_to_s16(long val)
904 {
905 	if (val <= -128000)
906 		return 0x8000;
907 	if (val >= 127875)
908 		return 0x7FE0;
909 	if (val < 0)
910 		return (val - 62) / 125 * 32;
911 	return (val + 62) / 125 * 32;
912 }
913 
914 static u8 hyst_to_reg(long val)
915 {
916 	if (val <= 0)
917 		return 0;
918 	if (val >= 30500)
919 		return 31;
920 	return (val + 500) / 1000;
921 }
922 
923 /*
924  * ADT7461 in compatibility mode is almost identical to LM90 except that
925  * attempts to write values that are outside the range 0 < temp < 127 are
926  * treated as the boundary value.
927  *
928  * ADT7461 in "extended mode" operation uses unsigned integers offset by
929  * 64 (e.g., 0 -> -64 degC).  The range is restricted to -64..191 degC.
930  */
931 static inline int temp_from_u8_adt7461(struct lm90_data *data, u8 val)
932 {
933 	if (data->flags & LM90_FLAG_ADT7461_EXT)
934 		return (val - 64) * 1000;
935 	return temp_from_s8(val);
936 }
937 
938 static inline int temp_from_u16_adt7461(struct lm90_data *data, u16 val)
939 {
940 	if (data->flags & LM90_FLAG_ADT7461_EXT)
941 		return (val - 0x4000) / 64 * 250;
942 	return temp_from_s16(val);
943 }
944 
945 static u8 temp_to_u8_adt7461(struct lm90_data *data, long val)
946 {
947 	if (data->flags & LM90_FLAG_ADT7461_EXT) {
948 		if (val <= -64000)
949 			return 0;
950 		if (val >= 191000)
951 			return 0xFF;
952 		return (val + 500 + 64000) / 1000;
953 	}
954 	if (val <= 0)
955 		return 0;
956 	if (val >= 127000)
957 		return 127;
958 	return (val + 500) / 1000;
959 }
960 
961 static u16 temp_to_u16_adt7461(struct lm90_data *data, long val)
962 {
963 	if (data->flags & LM90_FLAG_ADT7461_EXT) {
964 		if (val <= -64000)
965 			return 0;
966 		if (val >= 191750)
967 			return 0xFFC0;
968 		return (val + 64000 + 125) / 250 * 64;
969 	}
970 	if (val <= 0)
971 		return 0;
972 	if (val >= 127750)
973 		return 0x7FC0;
974 	return (val + 125) / 250 * 64;
975 }
976 
977 /* pec used for ADM1032 only */
978 static ssize_t pec_show(struct device *dev, struct device_attribute *dummy,
979 			char *buf)
980 {
981 	struct i2c_client *client = to_i2c_client(dev);
982 
983 	return sprintf(buf, "%d\n", !!(client->flags & I2C_CLIENT_PEC));
984 }
985 
986 static ssize_t pec_store(struct device *dev, struct device_attribute *dummy,
987 			 const char *buf, size_t count)
988 {
989 	struct i2c_client *client = to_i2c_client(dev);
990 	long val;
991 	int err;
992 
993 	err = kstrtol(buf, 10, &val);
994 	if (err < 0)
995 		return err;
996 
997 	switch (val) {
998 	case 0:
999 		client->flags &= ~I2C_CLIENT_PEC;
1000 		break;
1001 	case 1:
1002 		client->flags |= I2C_CLIENT_PEC;
1003 		break;
1004 	default:
1005 		return -EINVAL;
1006 	}
1007 
1008 	return count;
1009 }
1010 
1011 static DEVICE_ATTR_RW(pec);
1012 
1013 static int lm90_get_temp11(struct lm90_data *data, int index)
1014 {
1015 	s16 temp11 = data->temp11[index];
1016 	int temp;
1017 
1018 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1019 		temp = temp_from_u16_adt7461(data, temp11);
1020 	else if (data->kind == max6646)
1021 		temp = temp_from_u16(temp11);
1022 	else
1023 		temp = temp_from_s16(temp11);
1024 
1025 	/* +16 degrees offset for temp2 for the LM99 */
1026 	if (data->kind == lm99 && index <= 2)
1027 		temp += 16000;
1028 
1029 	return temp;
1030 }
1031 
1032 static int lm90_set_temp11(struct lm90_data *data, int index, long val)
1033 {
1034 	static struct reg {
1035 		u8 high;
1036 		u8 low;
1037 	} reg[] = {
1038 	[REMOTE_LOW] = { LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL },
1039 	[REMOTE_HIGH] = { LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL },
1040 	[REMOTE_OFFSET] = { LM90_REG_W_REMOTE_OFFSH, LM90_REG_W_REMOTE_OFFSL },
1041 	[REMOTE2_LOW] = { LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL },
1042 	[REMOTE2_HIGH] = { LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL }
1043 	};
1044 	struct i2c_client *client = data->client;
1045 	struct reg *regp = &reg[index];
1046 	int err;
1047 
1048 	/* +16 degrees offset for temp2 for the LM99 */
1049 	if (data->kind == lm99 && index <= 2) {
1050 		/* prevent integer underflow */
1051 		val = max(val, -128000l);
1052 		val -= 16000;
1053 	}
1054 
1055 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1056 		data->temp11[index] = temp_to_u16_adt7461(data, val);
1057 	else if (data->kind == max6646)
1058 		data->temp11[index] = temp_to_u8(val) << 8;
1059 	else if (data->flags & LM90_HAVE_REM_LIMIT_EXT)
1060 		data->temp11[index] = temp_to_s16(val);
1061 	else
1062 		data->temp11[index] = temp_to_s8(val) << 8;
1063 
1064 	lm90_select_remote_channel(data, index >= 3);
1065 	err = i2c_smbus_write_byte_data(client, regp->high,
1066 				  data->temp11[index] >> 8);
1067 	if (err < 0)
1068 		return err;
1069 	if (data->flags & LM90_HAVE_REM_LIMIT_EXT)
1070 		err = i2c_smbus_write_byte_data(client, regp->low,
1071 						data->temp11[index] & 0xff);
1072 
1073 	lm90_select_remote_channel(data, 0);
1074 	return err;
1075 }
1076 
1077 static int lm90_get_temp8(struct lm90_data *data, int index)
1078 {
1079 	s8 temp8 = data->temp8[index];
1080 	int temp;
1081 
1082 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1083 		temp = temp_from_u8_adt7461(data, temp8);
1084 	else if (data->kind == max6646)
1085 		temp = temp_from_u8(temp8);
1086 	else
1087 		temp = temp_from_s8(temp8);
1088 
1089 	/* +16 degrees offset for temp2 for the LM99 */
1090 	if (data->kind == lm99 && index == 3)
1091 		temp += 16000;
1092 
1093 	return temp;
1094 }
1095 
1096 static int lm90_set_temp8(struct lm90_data *data, int index, long val)
1097 {
1098 	static const u8 reg[TEMP8_REG_NUM] = {
1099 		LM90_REG_W_LOCAL_LOW,
1100 		LM90_REG_W_LOCAL_HIGH,
1101 		LM90_REG_W_LOCAL_CRIT,
1102 		LM90_REG_W_REMOTE_CRIT,
1103 		MAX6659_REG_W_LOCAL_EMERG,
1104 		MAX6659_REG_W_REMOTE_EMERG,
1105 		LM90_REG_W_REMOTE_CRIT,
1106 		MAX6659_REG_W_REMOTE_EMERG,
1107 	};
1108 	struct i2c_client *client = data->client;
1109 	int err;
1110 
1111 	/* +16 degrees offset for temp2 for the LM99 */
1112 	if (data->kind == lm99 && index == 3) {
1113 		/* prevent integer underflow */
1114 		val = max(val, -128000l);
1115 		val -= 16000;
1116 	}
1117 
1118 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1119 		data->temp8[index] = temp_to_u8_adt7461(data, val);
1120 	else if (data->kind == max6646)
1121 		data->temp8[index] = temp_to_u8(val);
1122 	else
1123 		data->temp8[index] = temp_to_s8(val);
1124 
1125 	lm90_select_remote_channel(data, index >= 6);
1126 	err = i2c_smbus_write_byte_data(client, reg[index], data->temp8[index]);
1127 	lm90_select_remote_channel(data, 0);
1128 
1129 	return err;
1130 }
1131 
1132 static int lm90_get_temphyst(struct lm90_data *data, int index)
1133 {
1134 	int temp;
1135 
1136 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1137 		temp = temp_from_u8_adt7461(data, data->temp8[index]);
1138 	else if (data->kind == max6646)
1139 		temp = temp_from_u8(data->temp8[index]);
1140 	else
1141 		temp = temp_from_s8(data->temp8[index]);
1142 
1143 	/* +16 degrees offset for temp2 for the LM99 */
1144 	if (data->kind == lm99 && index == 3)
1145 		temp += 16000;
1146 
1147 	return temp - temp_from_s8(data->temp_hyst);
1148 }
1149 
1150 static int lm90_set_temphyst(struct lm90_data *data, long val)
1151 {
1152 	struct i2c_client *client = data->client;
1153 	int temp;
1154 	int err;
1155 
1156 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1157 		temp = temp_from_u8_adt7461(data, data->temp8[LOCAL_CRIT]);
1158 	else if (data->kind == max6646)
1159 		temp = temp_from_u8(data->temp8[LOCAL_CRIT]);
1160 	else
1161 		temp = temp_from_s8(data->temp8[LOCAL_CRIT]);
1162 
1163 	/* prevent integer underflow */
1164 	val = max(val, -128000l);
1165 
1166 	data->temp_hyst = hyst_to_reg(temp - val);
1167 	err = i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST,
1168 					data->temp_hyst);
1169 	return err;
1170 }
1171 
1172 static const u8 lm90_temp_index[3] = {
1173 	LOCAL_TEMP, REMOTE_TEMP, REMOTE2_TEMP
1174 };
1175 
1176 static const u8 lm90_temp_min_index[3] = {
1177 	LOCAL_LOW, REMOTE_LOW, REMOTE2_LOW
1178 };
1179 
1180 static const u8 lm90_temp_max_index[3] = {
1181 	LOCAL_HIGH, REMOTE_HIGH, REMOTE2_HIGH
1182 };
1183 
1184 static const u8 lm90_temp_crit_index[3] = {
1185 	LOCAL_CRIT, REMOTE_CRIT, REMOTE2_CRIT
1186 };
1187 
1188 static const u8 lm90_temp_emerg_index[3] = {
1189 	LOCAL_EMERG, REMOTE_EMERG, REMOTE2_EMERG
1190 };
1191 
1192 static const u8 lm90_min_alarm_bits[3] = { 5, 3, 11 };
1193 static const u8 lm90_max_alarm_bits[3] = { 6, 4, 12 };
1194 static const u8 lm90_crit_alarm_bits[3] = { 0, 1, 9 };
1195 static const u8 lm90_emergency_alarm_bits[3] = { 15, 13, 14 };
1196 static const u8 lm90_fault_bits[3] = { 0, 2, 10 };
1197 
1198 static int lm90_temp_read(struct device *dev, u32 attr, int channel, long *val)
1199 {
1200 	struct lm90_data *data = dev_get_drvdata(dev);
1201 	int err;
1202 
1203 	mutex_lock(&data->update_lock);
1204 	err = lm90_update_device(dev);
1205 	mutex_unlock(&data->update_lock);
1206 	if (err)
1207 		return err;
1208 
1209 	switch (attr) {
1210 	case hwmon_temp_input:
1211 		*val = lm90_get_temp11(data, lm90_temp_index[channel]);
1212 		break;
1213 	case hwmon_temp_min_alarm:
1214 		*val = (data->alarms >> lm90_min_alarm_bits[channel]) & 1;
1215 		break;
1216 	case hwmon_temp_max_alarm:
1217 		*val = (data->alarms >> lm90_max_alarm_bits[channel]) & 1;
1218 		break;
1219 	case hwmon_temp_crit_alarm:
1220 		*val = (data->alarms >> lm90_crit_alarm_bits[channel]) & 1;
1221 		break;
1222 	case hwmon_temp_emergency_alarm:
1223 		*val = (data->alarms >> lm90_emergency_alarm_bits[channel]) & 1;
1224 		break;
1225 	case hwmon_temp_fault:
1226 		*val = (data->alarms >> lm90_fault_bits[channel]) & 1;
1227 		break;
1228 	case hwmon_temp_min:
1229 		if (channel == 0)
1230 			*val = lm90_get_temp8(data,
1231 					      lm90_temp_min_index[channel]);
1232 		else
1233 			*val = lm90_get_temp11(data,
1234 					       lm90_temp_min_index[channel]);
1235 		break;
1236 	case hwmon_temp_max:
1237 		if (channel == 0)
1238 			*val = lm90_get_temp8(data,
1239 					      lm90_temp_max_index[channel]);
1240 		else
1241 			*val = lm90_get_temp11(data,
1242 					       lm90_temp_max_index[channel]);
1243 		break;
1244 	case hwmon_temp_crit:
1245 		*val = lm90_get_temp8(data, lm90_temp_crit_index[channel]);
1246 		break;
1247 	case hwmon_temp_crit_hyst:
1248 		*val = lm90_get_temphyst(data, lm90_temp_crit_index[channel]);
1249 		break;
1250 	case hwmon_temp_emergency:
1251 		*val = lm90_get_temp8(data, lm90_temp_emerg_index[channel]);
1252 		break;
1253 	case hwmon_temp_emergency_hyst:
1254 		*val = lm90_get_temphyst(data, lm90_temp_emerg_index[channel]);
1255 		break;
1256 	case hwmon_temp_offset:
1257 		*val = lm90_get_temp11(data, REMOTE_OFFSET);
1258 		break;
1259 	default:
1260 		return -EOPNOTSUPP;
1261 	}
1262 	return 0;
1263 }
1264 
1265 static int lm90_temp_write(struct device *dev, u32 attr, int channel, long val)
1266 {
1267 	struct lm90_data *data = dev_get_drvdata(dev);
1268 	int err;
1269 
1270 	mutex_lock(&data->update_lock);
1271 
1272 	err = lm90_update_device(dev);
1273 	if (err)
1274 		goto error;
1275 
1276 	switch (attr) {
1277 	case hwmon_temp_min:
1278 		if (channel == 0)
1279 			err = lm90_set_temp8(data,
1280 					      lm90_temp_min_index[channel],
1281 					      val);
1282 		else
1283 			err = lm90_set_temp11(data,
1284 					      lm90_temp_min_index[channel],
1285 					      val);
1286 		break;
1287 	case hwmon_temp_max:
1288 		if (channel == 0)
1289 			err = lm90_set_temp8(data,
1290 					     lm90_temp_max_index[channel],
1291 					     val);
1292 		else
1293 			err = lm90_set_temp11(data,
1294 					      lm90_temp_max_index[channel],
1295 					      val);
1296 		break;
1297 	case hwmon_temp_crit:
1298 		err = lm90_set_temp8(data, lm90_temp_crit_index[channel], val);
1299 		break;
1300 	case hwmon_temp_crit_hyst:
1301 		err = lm90_set_temphyst(data, val);
1302 		break;
1303 	case hwmon_temp_emergency:
1304 		err = lm90_set_temp8(data, lm90_temp_emerg_index[channel], val);
1305 		break;
1306 	case hwmon_temp_offset:
1307 		err = lm90_set_temp11(data, REMOTE_OFFSET, val);
1308 		break;
1309 	default:
1310 		err = -EOPNOTSUPP;
1311 		break;
1312 	}
1313 error:
1314 	mutex_unlock(&data->update_lock);
1315 
1316 	return err;
1317 }
1318 
1319 static umode_t lm90_temp_is_visible(const void *data, u32 attr, int channel)
1320 {
1321 	switch (attr) {
1322 	case hwmon_temp_input:
1323 	case hwmon_temp_min_alarm:
1324 	case hwmon_temp_max_alarm:
1325 	case hwmon_temp_crit_alarm:
1326 	case hwmon_temp_emergency_alarm:
1327 	case hwmon_temp_emergency_hyst:
1328 	case hwmon_temp_fault:
1329 		return 0444;
1330 	case hwmon_temp_min:
1331 	case hwmon_temp_max:
1332 	case hwmon_temp_crit:
1333 	case hwmon_temp_emergency:
1334 	case hwmon_temp_offset:
1335 		return 0644;
1336 	case hwmon_temp_crit_hyst:
1337 		if (channel == 0)
1338 			return 0644;
1339 		return 0444;
1340 	default:
1341 		return 0;
1342 	}
1343 }
1344 
1345 static int lm90_chip_read(struct device *dev, u32 attr, int channel, long *val)
1346 {
1347 	struct lm90_data *data = dev_get_drvdata(dev);
1348 	int err;
1349 
1350 	mutex_lock(&data->update_lock);
1351 	err = lm90_update_device(dev);
1352 	mutex_unlock(&data->update_lock);
1353 	if (err)
1354 		return err;
1355 
1356 	switch (attr) {
1357 	case hwmon_chip_update_interval:
1358 		*val = data->update_interval;
1359 		break;
1360 	case hwmon_chip_alarms:
1361 		*val = data->alarms;
1362 		break;
1363 	default:
1364 		return -EOPNOTSUPP;
1365 	}
1366 
1367 	return 0;
1368 }
1369 
1370 static int lm90_chip_write(struct device *dev, u32 attr, int channel, long val)
1371 {
1372 	struct lm90_data *data = dev_get_drvdata(dev);
1373 	struct i2c_client *client = data->client;
1374 	int err;
1375 
1376 	mutex_lock(&data->update_lock);
1377 
1378 	err = lm90_update_device(dev);
1379 	if (err)
1380 		goto error;
1381 
1382 	switch (attr) {
1383 	case hwmon_chip_update_interval:
1384 		err = lm90_set_convrate(client, data,
1385 					clamp_val(val, 0, 100000));
1386 		break;
1387 	default:
1388 		err = -EOPNOTSUPP;
1389 		break;
1390 	}
1391 error:
1392 	mutex_unlock(&data->update_lock);
1393 
1394 	return err;
1395 }
1396 
1397 static umode_t lm90_chip_is_visible(const void *data, u32 attr, int channel)
1398 {
1399 	switch (attr) {
1400 	case hwmon_chip_update_interval:
1401 		return 0644;
1402 	case hwmon_chip_alarms:
1403 		return 0444;
1404 	default:
1405 		return 0;
1406 	}
1407 }
1408 
1409 static int lm90_read(struct device *dev, enum hwmon_sensor_types type,
1410 		     u32 attr, int channel, long *val)
1411 {
1412 	switch (type) {
1413 	case hwmon_chip:
1414 		return lm90_chip_read(dev, attr, channel, val);
1415 	case hwmon_temp:
1416 		return lm90_temp_read(dev, attr, channel, val);
1417 	default:
1418 		return -EOPNOTSUPP;
1419 	}
1420 }
1421 
1422 static int lm90_write(struct device *dev, enum hwmon_sensor_types type,
1423 		      u32 attr, int channel, long val)
1424 {
1425 	switch (type) {
1426 	case hwmon_chip:
1427 		return lm90_chip_write(dev, attr, channel, val);
1428 	case hwmon_temp:
1429 		return lm90_temp_write(dev, attr, channel, val);
1430 	default:
1431 		return -EOPNOTSUPP;
1432 	}
1433 }
1434 
1435 static umode_t lm90_is_visible(const void *data, enum hwmon_sensor_types type,
1436 			       u32 attr, int channel)
1437 {
1438 	switch (type) {
1439 	case hwmon_chip:
1440 		return lm90_chip_is_visible(data, attr, channel);
1441 	case hwmon_temp:
1442 		return lm90_temp_is_visible(data, attr, channel);
1443 	default:
1444 		return 0;
1445 	}
1446 }
1447 
1448 /* Return 0 if detection is successful, -ENODEV otherwise */
1449 static int lm90_detect(struct i2c_client *client,
1450 		       struct i2c_board_info *info)
1451 {
1452 	struct i2c_adapter *adapter = client->adapter;
1453 	int address = client->addr;
1454 	const char *name = NULL;
1455 	int man_id, chip_id, config1, config2, convrate;
1456 
1457 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
1458 		return -ENODEV;
1459 
1460 	/* detection and identification */
1461 	man_id = i2c_smbus_read_byte_data(client, LM90_REG_R_MAN_ID);
1462 	chip_id = i2c_smbus_read_byte_data(client, LM90_REG_R_CHIP_ID);
1463 	config1 = i2c_smbus_read_byte_data(client, LM90_REG_R_CONFIG1);
1464 	convrate = i2c_smbus_read_byte_data(client, LM90_REG_R_CONVRATE);
1465 	if (man_id < 0 || chip_id < 0 || config1 < 0 || convrate < 0)
1466 		return -ENODEV;
1467 
1468 	if (man_id == 0x01 || man_id == 0x5C || man_id == 0x41) {
1469 		config2 = i2c_smbus_read_byte_data(client, LM90_REG_R_CONFIG2);
1470 		if (config2 < 0)
1471 			return -ENODEV;
1472 	} else
1473 		config2 = 0;		/* Make compiler happy */
1474 
1475 	if ((address == 0x4C || address == 0x4D)
1476 	 && man_id == 0x01) { /* National Semiconductor */
1477 		if ((config1 & 0x2A) == 0x00
1478 		 && (config2 & 0xF8) == 0x00
1479 		 && convrate <= 0x09) {
1480 			if (address == 0x4C
1481 			 && (chip_id & 0xF0) == 0x20) { /* LM90 */
1482 				name = "lm90";
1483 			} else
1484 			if ((chip_id & 0xF0) == 0x30) { /* LM89/LM99 */
1485 				name = "lm99";
1486 				dev_info(&adapter->dev,
1487 					 "Assuming LM99 chip at 0x%02x\n",
1488 					 address);
1489 				dev_info(&adapter->dev,
1490 					 "If it is an LM89, instantiate it "
1491 					 "with the new_device sysfs "
1492 					 "interface\n");
1493 			} else
1494 			if (address == 0x4C
1495 			 && (chip_id & 0xF0) == 0x10) { /* LM86 */
1496 				name = "lm86";
1497 			}
1498 		}
1499 	} else
1500 	if ((address == 0x4C || address == 0x4D)
1501 	 && man_id == 0x41) { /* Analog Devices */
1502 		if ((chip_id & 0xF0) == 0x40 /* ADM1032 */
1503 		 && (config1 & 0x3F) == 0x00
1504 		 && convrate <= 0x0A) {
1505 			name = "adm1032";
1506 			/*
1507 			 * The ADM1032 supports PEC, but only if combined
1508 			 * transactions are not used.
1509 			 */
1510 			if (i2c_check_functionality(adapter,
1511 						    I2C_FUNC_SMBUS_BYTE))
1512 				info->flags |= I2C_CLIENT_PEC;
1513 		} else
1514 		if (chip_id == 0x51 /* ADT7461 */
1515 		 && (config1 & 0x1B) == 0x00
1516 		 && convrate <= 0x0A) {
1517 			name = "adt7461";
1518 		} else
1519 		if (chip_id == 0x57 /* ADT7461A, NCT1008 */
1520 		 && (config1 & 0x1B) == 0x00
1521 		 && convrate <= 0x0A) {
1522 			name = "adt7461a";
1523 		}
1524 	} else
1525 	if (man_id == 0x4D) { /* Maxim */
1526 		int emerg, emerg2, status2;
1527 
1528 		/*
1529 		 * We read MAX6659_REG_R_REMOTE_EMERG twice, and re-read
1530 		 * LM90_REG_R_MAN_ID in between. If MAX6659_REG_R_REMOTE_EMERG
1531 		 * exists, both readings will reflect the same value. Otherwise,
1532 		 * the readings will be different.
1533 		 */
1534 		emerg = i2c_smbus_read_byte_data(client,
1535 						 MAX6659_REG_R_REMOTE_EMERG);
1536 		man_id = i2c_smbus_read_byte_data(client,
1537 						  LM90_REG_R_MAN_ID);
1538 		emerg2 = i2c_smbus_read_byte_data(client,
1539 						  MAX6659_REG_R_REMOTE_EMERG);
1540 		status2 = i2c_smbus_read_byte_data(client,
1541 						   MAX6696_REG_R_STATUS2);
1542 		if (emerg < 0 || man_id < 0 || emerg2 < 0 || status2 < 0)
1543 			return -ENODEV;
1544 
1545 		/*
1546 		 * The MAX6657, MAX6658 and MAX6659 do NOT have a chip_id
1547 		 * register. Reading from that address will return the last
1548 		 * read value, which in our case is those of the man_id
1549 		 * register. Likewise, the config1 register seems to lack a
1550 		 * low nibble, so the value will be those of the previous
1551 		 * read, so in our case those of the man_id register.
1552 		 * MAX6659 has a third set of upper temperature limit registers.
1553 		 * Those registers also return values on MAX6657 and MAX6658,
1554 		 * thus the only way to detect MAX6659 is by its address.
1555 		 * For this reason it will be mis-detected as MAX6657 if its
1556 		 * address is 0x4C.
1557 		 */
1558 		if (chip_id == man_id
1559 		 && (address == 0x4C || address == 0x4D || address == 0x4E)
1560 		 && (config1 & 0x1F) == (man_id & 0x0F)
1561 		 && convrate <= 0x09) {
1562 			if (address == 0x4C)
1563 				name = "max6657";
1564 			else
1565 				name = "max6659";
1566 		} else
1567 		/*
1568 		 * Even though MAX6695 and MAX6696 do not have a chip ID
1569 		 * register, reading it returns 0x01. Bit 4 of the config1
1570 		 * register is unused and should return zero when read. Bit 0 of
1571 		 * the status2 register is unused and should return zero when
1572 		 * read.
1573 		 *
1574 		 * MAX6695 and MAX6696 have an additional set of temperature
1575 		 * limit registers. We can detect those chips by checking if
1576 		 * one of those registers exists.
1577 		 */
1578 		if (chip_id == 0x01
1579 		 && (config1 & 0x10) == 0x00
1580 		 && (status2 & 0x01) == 0x00
1581 		 && emerg == emerg2
1582 		 && convrate <= 0x07) {
1583 			name = "max6696";
1584 		} else
1585 		/*
1586 		 * The chip_id register of the MAX6680 and MAX6681 holds the
1587 		 * revision of the chip. The lowest bit of the config1 register
1588 		 * is unused and should return zero when read, so should the
1589 		 * second to last bit of config1 (software reset).
1590 		 */
1591 		if (chip_id == 0x01
1592 		 && (config1 & 0x03) == 0x00
1593 		 && convrate <= 0x07) {
1594 			name = "max6680";
1595 		} else
1596 		/*
1597 		 * The chip_id register of the MAX6646/6647/6649 holds the
1598 		 * revision of the chip. The lowest 6 bits of the config1
1599 		 * register are unused and should return zero when read.
1600 		 */
1601 		if (chip_id == 0x59
1602 		 && (config1 & 0x3f) == 0x00
1603 		 && convrate <= 0x07) {
1604 			name = "max6646";
1605 		} else
1606 		/*
1607 		 * The chip_id of the MAX6654 holds the revision of the chip.
1608 		 * The lowest 3 bits of the config1 register are unused and
1609 		 * should return zero when read.
1610 		 */
1611 		if (chip_id == 0x08
1612 		 && (config1 & 0x07) == 0x00
1613 		 && convrate <= 0x07) {
1614 			name = "max6654";
1615 		}
1616 	} else
1617 	if (address == 0x4C
1618 	 && man_id == 0x5C) { /* Winbond/Nuvoton */
1619 		if ((config1 & 0x2A) == 0x00
1620 		 && (config2 & 0xF8) == 0x00) {
1621 			if (chip_id == 0x01 /* W83L771W/G */
1622 			 && convrate <= 0x09) {
1623 				name = "w83l771";
1624 			} else
1625 			if ((chip_id & 0xFE) == 0x10 /* W83L771AWG/ASG */
1626 			 && convrate <= 0x08) {
1627 				name = "w83l771";
1628 			}
1629 		}
1630 	} else
1631 	if (address >= 0x48 && address <= 0x4F
1632 	 && man_id == 0xA1) { /*  NXP Semiconductor/Philips */
1633 		if (chip_id == 0x00
1634 		 && (config1 & 0x2A) == 0x00
1635 		 && (config2 & 0xFE) == 0x00
1636 		 && convrate <= 0x09) {
1637 			name = "sa56004";
1638 		}
1639 	} else
1640 	if ((address == 0x4C || address == 0x4D)
1641 	 && man_id == 0x47) { /* GMT */
1642 		if (chip_id == 0x01 /* G781 */
1643 		 && (config1 & 0x3F) == 0x00
1644 		 && convrate <= 0x08)
1645 			name = "g781";
1646 	} else
1647 	if (man_id == 0x55 && chip_id == 0x00 &&
1648 	    (config1 & 0x1B) == 0x00 && convrate <= 0x09) {
1649 		int local_ext, conalert, chen, dfc;
1650 
1651 		local_ext = i2c_smbus_read_byte_data(client,
1652 						     TMP451_REG_R_LOCAL_TEMPL);
1653 		conalert = i2c_smbus_read_byte_data(client,
1654 						    TMP451_REG_CONALERT);
1655 		chen = i2c_smbus_read_byte_data(client, TMP461_REG_CHEN);
1656 		dfc = i2c_smbus_read_byte_data(client, TMP461_REG_DFC);
1657 
1658 		if ((local_ext & 0x0F) == 0x00 &&
1659 		    (conalert & 0xf1) == 0x01 &&
1660 		    (chen & 0xfc) == 0x00 &&
1661 		    (dfc & 0xfc) == 0x00) {
1662 			if (address == 0x4c && !(chen & 0x03))
1663 				name = "tmp451";
1664 			else if (address >= 0x48 && address <= 0x4f)
1665 				name = "tmp461";
1666 		}
1667 	}
1668 
1669 	if (!name) { /* identification failed */
1670 		dev_dbg(&adapter->dev,
1671 			"Unsupported chip at 0x%02x (man_id=0x%02X, "
1672 			"chip_id=0x%02X)\n", address, man_id, chip_id);
1673 		return -ENODEV;
1674 	}
1675 
1676 	strlcpy(info->type, name, I2C_NAME_SIZE);
1677 
1678 	return 0;
1679 }
1680 
1681 static void lm90_restore_conf(void *_data)
1682 {
1683 	struct lm90_data *data = _data;
1684 	struct i2c_client *client = data->client;
1685 
1686 	/* Restore initial configuration */
1687 	lm90_write_convrate(data, data->convrate_orig);
1688 	i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
1689 				  data->config_orig);
1690 }
1691 
1692 static int lm90_init_client(struct i2c_client *client, struct lm90_data *data)
1693 {
1694 	int config, convrate;
1695 
1696 	convrate = lm90_read_reg(client, LM90_REG_R_CONVRATE);
1697 	if (convrate < 0)
1698 		return convrate;
1699 	data->convrate_orig = convrate;
1700 
1701 	/*
1702 	 * Start the conversions.
1703 	 */
1704 	config = lm90_read_reg(client, LM90_REG_R_CONFIG1);
1705 	if (config < 0)
1706 		return config;
1707 	data->config_orig = config;
1708 	data->config = config;
1709 
1710 	lm90_set_convrate(client, data, 500); /* 500ms; 2Hz conversion rate */
1711 
1712 	/* Check Temperature Range Select */
1713 	if (data->flags & LM90_HAVE_EXTENDED_TEMP) {
1714 		if (config & 0x04)
1715 			data->flags |= LM90_FLAG_ADT7461_EXT;
1716 	}
1717 
1718 	/*
1719 	 * Put MAX6680/MAX8881 into extended resolution (bit 0x10,
1720 	 * 0.125 degree resolution) and range (0x08, extend range
1721 	 * to -64 degree) mode for the remote temperature sensor.
1722 	 */
1723 	if (data->kind == max6680)
1724 		config |= 0x18;
1725 
1726 	/*
1727 	 * Put MAX6654 into extended range (0x20, extend minimum range from
1728 	 * 0 degrees to -64 degrees). Note that extended resolution is not
1729 	 * possible on the MAX6654 unless conversion rate is set to 1 Hz or
1730 	 * slower, which is intentionally not done by default.
1731 	 */
1732 	if (data->kind == max6654)
1733 		config |= 0x20;
1734 
1735 	/*
1736 	 * Select external channel 0 for max6695/96
1737 	 */
1738 	if (data->kind == max6696)
1739 		config &= ~0x08;
1740 
1741 	/*
1742 	 * Interrupt is enabled by default on reset, but it may be disabled
1743 	 * by bootloader, unmask it.
1744 	 */
1745 	if (client->irq)
1746 		config &= ~0x80;
1747 
1748 	config &= 0xBF;	/* run */
1749 	lm90_update_confreg(data, config);
1750 
1751 	return devm_add_action_or_reset(&client->dev, lm90_restore_conf, data);
1752 }
1753 
1754 static bool lm90_is_tripped(struct i2c_client *client, u16 *status)
1755 {
1756 	struct lm90_data *data = i2c_get_clientdata(client);
1757 	int st, st2 = 0;
1758 
1759 	st = lm90_read_reg(client, LM90_REG_R_STATUS);
1760 	if (st < 0)
1761 		return false;
1762 
1763 	if (data->kind == max6696) {
1764 		st2 = lm90_read_reg(client, MAX6696_REG_R_STATUS2);
1765 		if (st2 < 0)
1766 			return false;
1767 	}
1768 
1769 	*status = st | (st2 << 8);
1770 
1771 	if ((st & 0x7f) == 0 && (st2 & 0xfe) == 0)
1772 		return false;
1773 
1774 	if ((st & (LM90_STATUS_LLOW | LM90_STATUS_LHIGH | LM90_STATUS_LTHRM)) ||
1775 	    (st2 & MAX6696_STATUS2_LOT2))
1776 		dev_dbg(&client->dev,
1777 			"temp%d out of range, please check!\n", 1);
1778 	if ((st & (LM90_STATUS_RLOW | LM90_STATUS_RHIGH | LM90_STATUS_RTHRM)) ||
1779 	    (st2 & MAX6696_STATUS2_ROT2))
1780 		dev_dbg(&client->dev,
1781 			"temp%d out of range, please check!\n", 2);
1782 	if (st & LM90_STATUS_ROPEN)
1783 		dev_dbg(&client->dev,
1784 			"temp%d diode open, please check!\n", 2);
1785 	if (st2 & (MAX6696_STATUS2_R2LOW | MAX6696_STATUS2_R2HIGH |
1786 		   MAX6696_STATUS2_R2THRM | MAX6696_STATUS2_R2OT2))
1787 		dev_dbg(&client->dev,
1788 			"temp%d out of range, please check!\n", 3);
1789 	if (st2 & MAX6696_STATUS2_R2OPEN)
1790 		dev_dbg(&client->dev,
1791 			"temp%d diode open, please check!\n", 3);
1792 
1793 	if (st & LM90_STATUS_LLOW)
1794 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1795 				   hwmon_temp_min, 0);
1796 	if (st & LM90_STATUS_RLOW)
1797 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1798 				   hwmon_temp_min, 1);
1799 	if (st2 & MAX6696_STATUS2_R2LOW)
1800 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1801 				   hwmon_temp_min, 2);
1802 	if (st & LM90_STATUS_LHIGH)
1803 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1804 				   hwmon_temp_max, 0);
1805 	if (st & LM90_STATUS_RHIGH)
1806 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1807 				   hwmon_temp_max, 1);
1808 	if (st2 & MAX6696_STATUS2_R2HIGH)
1809 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1810 				   hwmon_temp_max, 2);
1811 
1812 	return true;
1813 }
1814 
1815 static irqreturn_t lm90_irq_thread(int irq, void *dev_id)
1816 {
1817 	struct i2c_client *client = dev_id;
1818 	u16 status;
1819 
1820 	if (lm90_is_tripped(client, &status))
1821 		return IRQ_HANDLED;
1822 	else
1823 		return IRQ_NONE;
1824 }
1825 
1826 static void lm90_remove_pec(void *dev)
1827 {
1828 	device_remove_file(dev, &dev_attr_pec);
1829 }
1830 
1831 static void lm90_regulator_disable(void *regulator)
1832 {
1833 	regulator_disable(regulator);
1834 }
1835 
1836 
1837 static const struct hwmon_ops lm90_ops = {
1838 	.is_visible = lm90_is_visible,
1839 	.read = lm90_read,
1840 	.write = lm90_write,
1841 };
1842 
1843 static int lm90_probe(struct i2c_client *client)
1844 {
1845 	struct device *dev = &client->dev;
1846 	struct i2c_adapter *adapter = client->adapter;
1847 	struct hwmon_channel_info *info;
1848 	struct regulator *regulator;
1849 	struct device *hwmon_dev;
1850 	struct lm90_data *data;
1851 	int err;
1852 
1853 	regulator = devm_regulator_get(dev, "vcc");
1854 	if (IS_ERR(regulator))
1855 		return PTR_ERR(regulator);
1856 
1857 	err = regulator_enable(regulator);
1858 	if (err < 0) {
1859 		dev_err(dev, "Failed to enable regulator: %d\n", err);
1860 		return err;
1861 	}
1862 
1863 	err = devm_add_action_or_reset(dev, lm90_regulator_disable, regulator);
1864 	if (err)
1865 		return err;
1866 
1867 	data = devm_kzalloc(dev, sizeof(struct lm90_data), GFP_KERNEL);
1868 	if (!data)
1869 		return -ENOMEM;
1870 
1871 	data->client = client;
1872 	i2c_set_clientdata(client, data);
1873 	mutex_init(&data->update_lock);
1874 
1875 	/* Set the device type */
1876 	if (client->dev.of_node)
1877 		data->kind = (enum chips)of_device_get_match_data(&client->dev);
1878 	else
1879 		data->kind = i2c_match_id(lm90_id, client)->driver_data;
1880 	if (data->kind == adm1032) {
1881 		if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
1882 			client->flags &= ~I2C_CLIENT_PEC;
1883 	}
1884 
1885 	/*
1886 	 * Different devices have different alarm bits triggering the
1887 	 * ALERT# output
1888 	 */
1889 	data->alert_alarms = lm90_params[data->kind].alert_alarms;
1890 
1891 	/* Set chip capabilities */
1892 	data->flags = lm90_params[data->kind].flags;
1893 
1894 	data->chip.ops = &lm90_ops;
1895 	data->chip.info = data->info;
1896 
1897 	data->info[0] = HWMON_CHANNEL_INFO(chip,
1898 		HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL | HWMON_C_ALARMS);
1899 	data->info[1] = &data->temp_info;
1900 
1901 	info = &data->temp_info;
1902 	info->type = hwmon_temp;
1903 	info->config = data->channel_config;
1904 
1905 	data->channel_config[0] = HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
1906 		HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MIN_ALARM |
1907 		HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM;
1908 	data->channel_config[1] = HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
1909 		HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_MIN_ALARM |
1910 		HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM | HWMON_T_FAULT;
1911 
1912 	if (data->flags & LM90_HAVE_OFFSET)
1913 		data->channel_config[1] |= HWMON_T_OFFSET;
1914 
1915 	if (data->flags & LM90_HAVE_EMERGENCY) {
1916 		data->channel_config[0] |= HWMON_T_EMERGENCY |
1917 			HWMON_T_EMERGENCY_HYST;
1918 		data->channel_config[1] |= HWMON_T_EMERGENCY |
1919 			HWMON_T_EMERGENCY_HYST;
1920 	}
1921 
1922 	if (data->flags & LM90_HAVE_EMERGENCY_ALARM) {
1923 		data->channel_config[0] |= HWMON_T_EMERGENCY_ALARM;
1924 		data->channel_config[1] |= HWMON_T_EMERGENCY_ALARM;
1925 	}
1926 
1927 	if (data->flags & LM90_HAVE_TEMP3) {
1928 		data->channel_config[2] = HWMON_T_INPUT |
1929 			HWMON_T_MIN | HWMON_T_MAX |
1930 			HWMON_T_CRIT | HWMON_T_CRIT_HYST |
1931 			HWMON_T_EMERGENCY | HWMON_T_EMERGENCY_HYST |
1932 			HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM |
1933 			HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY_ALARM |
1934 			HWMON_T_FAULT;
1935 	}
1936 
1937 	data->reg_local_ext = lm90_params[data->kind].reg_local_ext;
1938 
1939 	/* Set maximum conversion rate */
1940 	data->max_convrate = lm90_params[data->kind].max_convrate;
1941 
1942 	/* Initialize the LM90 chip */
1943 	err = lm90_init_client(client, data);
1944 	if (err < 0) {
1945 		dev_err(dev, "Failed to initialize device\n");
1946 		return err;
1947 	}
1948 
1949 	/*
1950 	 * The 'pec' attribute is attached to the i2c device and thus created
1951 	 * separately.
1952 	 */
1953 	if (client->flags & I2C_CLIENT_PEC) {
1954 		err = device_create_file(dev, &dev_attr_pec);
1955 		if (err)
1956 			return err;
1957 		err = devm_add_action_or_reset(dev, lm90_remove_pec, dev);
1958 		if (err)
1959 			return err;
1960 	}
1961 
1962 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
1963 							 data, &data->chip,
1964 							 NULL);
1965 	if (IS_ERR(hwmon_dev))
1966 		return PTR_ERR(hwmon_dev);
1967 
1968 	data->hwmon_dev = hwmon_dev;
1969 
1970 	if (client->irq) {
1971 		dev_dbg(dev, "IRQ: %d\n", client->irq);
1972 		err = devm_request_threaded_irq(dev, client->irq,
1973 						NULL, lm90_irq_thread,
1974 						IRQF_ONESHOT, "lm90", client);
1975 		if (err < 0) {
1976 			dev_err(dev, "cannot request IRQ %d\n", client->irq);
1977 			return err;
1978 		}
1979 	}
1980 
1981 	return 0;
1982 }
1983 
1984 static void lm90_alert(struct i2c_client *client, enum i2c_alert_protocol type,
1985 		       unsigned int flag)
1986 {
1987 	u16 alarms;
1988 
1989 	if (type != I2C_PROTOCOL_SMBUS_ALERT)
1990 		return;
1991 
1992 	if (lm90_is_tripped(client, &alarms)) {
1993 		/*
1994 		 * Disable ALERT# output, because these chips don't implement
1995 		 * SMBus alert correctly; they should only hold the alert line
1996 		 * low briefly.
1997 		 */
1998 		struct lm90_data *data = i2c_get_clientdata(client);
1999 
2000 		if ((data->flags & LM90_HAVE_BROKEN_ALERT) &&
2001 		    (alarms & data->alert_alarms)) {
2002 			dev_dbg(&client->dev, "Disabling ALERT#\n");
2003 			lm90_update_confreg(data, data->config | 0x80);
2004 		}
2005 	} else {
2006 		dev_dbg(&client->dev, "Everything OK\n");
2007 	}
2008 }
2009 
2010 static int __maybe_unused lm90_suspend(struct device *dev)
2011 {
2012 	struct lm90_data *data = dev_get_drvdata(dev);
2013 	struct i2c_client *client = data->client;
2014 
2015 	if (client->irq)
2016 		disable_irq(client->irq);
2017 
2018 	return 0;
2019 }
2020 
2021 static int __maybe_unused lm90_resume(struct device *dev)
2022 {
2023 	struct lm90_data *data = dev_get_drvdata(dev);
2024 	struct i2c_client *client = data->client;
2025 
2026 	if (client->irq)
2027 		enable_irq(client->irq);
2028 
2029 	return 0;
2030 }
2031 
2032 static SIMPLE_DEV_PM_OPS(lm90_pm_ops, lm90_suspend, lm90_resume);
2033 
2034 static struct i2c_driver lm90_driver = {
2035 	.class		= I2C_CLASS_HWMON,
2036 	.driver = {
2037 		.name	= "lm90",
2038 		.of_match_table = of_match_ptr(lm90_of_match),
2039 		.pm	= &lm90_pm_ops,
2040 	},
2041 	.probe_new	= lm90_probe,
2042 	.alert		= lm90_alert,
2043 	.id_table	= lm90_id,
2044 	.detect		= lm90_detect,
2045 	.address_list	= normal_i2c,
2046 };
2047 
2048 module_i2c_driver(lm90_driver);
2049 
2050 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
2051 MODULE_DESCRIPTION("LM90/ADM1032 driver");
2052 MODULE_LICENSE("GPL");
2053