xref: /openbmc/linux/drivers/hwmon/lm90.c (revision 10756dc5)
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 be
39  * at 9 different addresses, similar to MAX6680/MAX6681. The MAX6654 is similar
40  * to MAX6657/MAX6658/MAX6659, but does not support critical temperature
41  * limits. Extended range is available by setting the configuration register
42  * accordingly, and is done during initialization. Extended precision is only
43  * available at conversion rates of 1 Hz and slower. Note that extended
44  * precision is not enabled by default, as this driver initializes all chips
45  * to 2 Hz by design.
46  *
47  * This driver also supports the MAX6646, MAX6647, MAX6648, MAX6649 and
48  * MAX6692 chips made by Maxim.  These are again similar to the LM86,
49  * but they use unsigned temperature values and can report temperatures
50  * from 0 to 145 degrees.
51  *
52  * This driver also supports the MAX6680 and MAX6681, two other sensor
53  * chips made by Maxim. These are quite similar to the other Maxim
54  * chips. The MAX6680 and MAX6681 only differ in the pinout so they can
55  * be treated identically.
56  *
57  * This driver also supports the MAX6695 and MAX6696, two other sensor
58  * chips made by Maxim. These are also quite similar to other Maxim
59  * chips, but support three temperature sensors instead of two. MAX6695
60  * and MAX6696 only differ in the pinout so they can be treated identically.
61  *
62  * This driver also supports ADT7461 and ADT7461A from Analog Devices as well as
63  * NCT1008 from ON Semiconductor. The chips are supported in both compatibility
64  * and extended mode. They are mostly compatible with LM90 except for a data
65  * format difference for the temperature value registers.
66  *
67  * This driver also supports the SA56004 from Philips. This device is
68  * pin-compatible with the LM86, the ED/EDP parts are also address-compatible.
69  *
70  * This driver also supports the G781 from GMT. This device is compatible
71  * with the ADM1032.
72  *
73  * This driver also supports TMP451 and TMP461 from Texas Instruments.
74  * Those devices are supported in both compatibility and extended mode.
75  * They are mostly compatible with ADT7461 except for local temperature
76  * low byte register and max conversion rate.
77  *
78  * Since the LM90 was the first chipset supported by this driver, most
79  * comments will refer to this chipset, but are actually general and
80  * concern all supported chipsets, unless mentioned otherwise.
81  */
82 
83 #include <linux/module.h>
84 #include <linux/init.h>
85 #include <linux/slab.h>
86 #include <linux/jiffies.h>
87 #include <linux/i2c.h>
88 #include <linux/hwmon.h>
89 #include <linux/err.h>
90 #include <linux/mutex.h>
91 #include <linux/of_device.h>
92 #include <linux/sysfs.h>
93 #include <linux/interrupt.h>
94 #include <linux/regulator/consumer.h>
95 
96 /*
97  * Addresses to scan
98  * Address is fully defined internally and cannot be changed except for
99  * MAX6659, MAX6680 and MAX6681.
100  * LM86, LM89, LM90, LM99, ADM1032, ADM1032-1, ADT7461, ADT7461A, MAX6649,
101  * MAX6657, MAX6658, NCT1008 and W83L771 have address 0x4c.
102  * ADM1032-2, ADT7461-2, ADT7461A-2, LM89-1, LM99-1, MAX6646, and NCT1008D
103  * have address 0x4d.
104  * MAX6647 has address 0x4e.
105  * MAX6659 can have address 0x4c, 0x4d or 0x4e.
106  * MAX6654, MAX6680, and MAX6681 can have address 0x18, 0x19, 0x1a, 0x29,
107  * 0x2a, 0x2b, 0x4c, 0x4d or 0x4e.
108  * SA56004 can have address 0x48 through 0x4F.
109  */
110 
111 static const unsigned short normal_i2c[] = {
112 	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x48, 0x49, 0x4a, 0x4b, 0x4c,
113 	0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
114 
115 enum chips { lm90, adm1032, lm99, lm86, max6657, max6659, adt7461, max6680,
116 	max6646, w83l771, max6696, sa56004, g781, tmp451, tmp461, max6654 };
117 
118 /*
119  * The LM90 registers
120  */
121 
122 #define LM90_REG_R_MAN_ID		0xFE
123 #define LM90_REG_R_CHIP_ID		0xFF
124 #define LM90_REG_R_CONFIG1		0x03
125 #define LM90_REG_W_CONFIG1		0x09
126 #define LM90_REG_R_CONFIG2		0xBF
127 #define LM90_REG_W_CONFIG2		0xBF
128 #define LM90_REG_R_CONVRATE		0x04
129 #define LM90_REG_W_CONVRATE		0x0A
130 #define LM90_REG_R_STATUS		0x02
131 #define LM90_REG_R_LOCAL_TEMP		0x00
132 #define LM90_REG_R_LOCAL_HIGH		0x05
133 #define LM90_REG_W_LOCAL_HIGH		0x0B
134 #define LM90_REG_R_LOCAL_LOW		0x06
135 #define LM90_REG_W_LOCAL_LOW		0x0C
136 #define LM90_REG_R_LOCAL_CRIT		0x20
137 #define LM90_REG_W_LOCAL_CRIT		0x20
138 #define LM90_REG_R_REMOTE_TEMPH		0x01
139 #define LM90_REG_R_REMOTE_TEMPL		0x10
140 #define LM90_REG_R_REMOTE_OFFSH		0x11
141 #define LM90_REG_W_REMOTE_OFFSH		0x11
142 #define LM90_REG_R_REMOTE_OFFSL		0x12
143 #define LM90_REG_W_REMOTE_OFFSL		0x12
144 #define LM90_REG_R_REMOTE_HIGHH		0x07
145 #define LM90_REG_W_REMOTE_HIGHH		0x0D
146 #define LM90_REG_R_REMOTE_HIGHL		0x13
147 #define LM90_REG_W_REMOTE_HIGHL		0x13
148 #define LM90_REG_R_REMOTE_LOWH		0x08
149 #define LM90_REG_W_REMOTE_LOWH		0x0E
150 #define LM90_REG_R_REMOTE_LOWL		0x14
151 #define LM90_REG_W_REMOTE_LOWL		0x14
152 #define LM90_REG_R_REMOTE_CRIT		0x19
153 #define LM90_REG_W_REMOTE_CRIT		0x19
154 #define LM90_REG_R_TCRIT_HYST		0x21
155 #define LM90_REG_W_TCRIT_HYST		0x21
156 
157 /* MAX6646/6647/6649/6654/6657/6658/6659/6695/6696 registers */
158 
159 #define MAX6657_REG_R_LOCAL_TEMPL	0x11
160 #define MAX6696_REG_R_STATUS2		0x12
161 #define MAX6659_REG_R_REMOTE_EMERG	0x16
162 #define MAX6659_REG_W_REMOTE_EMERG	0x16
163 #define MAX6659_REG_R_LOCAL_EMERG	0x17
164 #define MAX6659_REG_W_LOCAL_EMERG	0x17
165 
166 /*  SA56004 registers */
167 
168 #define SA56004_REG_R_LOCAL_TEMPL 0x22
169 
170 #define LM90_MAX_CONVRATE_MS	16000	/* Maximum conversion rate in ms */
171 
172 /* TMP451/TMP461 registers */
173 #define TMP451_REG_R_LOCAL_TEMPL	0x15
174 #define TMP451_REG_CONALERT		0x22
175 
176 #define TMP461_REG_CHEN			0x16
177 #define TMP461_REG_DFC			0x24
178 
179 /*
180  * Device flags
181  */
182 #define LM90_FLAG_ADT7461_EXT	(1 << 0) /* ADT7461 extended mode	*/
183 /* Device features */
184 #define LM90_HAVE_OFFSET	(1 << 1) /* temperature offset register	*/
185 #define LM90_HAVE_REM_LIMIT_EXT	(1 << 3) /* extended remote limit	*/
186 #define LM90_HAVE_EMERGENCY	(1 << 4) /* 3rd upper (emergency) limit	*/
187 #define LM90_HAVE_EMERGENCY_ALARM (1 << 5)/* emergency alarm		*/
188 #define LM90_HAVE_TEMP3		(1 << 6) /* 3rd temperature sensor	*/
189 #define LM90_HAVE_BROKEN_ALERT	(1 << 7) /* Broken alert		*/
190 #define LM90_HAVE_EXTENDED_TEMP	(1 << 8) /* extended temperature support*/
191 #define LM90_PAUSE_FOR_CONFIG	(1 << 9) /* Pause conversion for config	*/
192 #define LM90_HAVE_CRIT		(1 << 10)/* Chip supports CRIT/OVERT register	*/
193 #define LM90_HAVE_CRIT_ALRM_SWP	(1 << 11)/* critical alarm bits swapped	*/
194 
195 /* LM90 status */
196 #define LM90_STATUS_LTHRM	(1 << 0) /* local THERM limit tripped */
197 #define LM90_STATUS_RTHRM	(1 << 1) /* remote THERM limit tripped */
198 #define LM90_STATUS_ROPEN	(1 << 2) /* remote is an open circuit */
199 #define LM90_STATUS_RLOW	(1 << 3) /* remote low temp limit tripped */
200 #define LM90_STATUS_RHIGH	(1 << 4) /* remote high temp limit tripped */
201 #define LM90_STATUS_LLOW	(1 << 5) /* local low temp limit tripped */
202 #define LM90_STATUS_LHIGH	(1 << 6) /* local high temp limit tripped */
203 #define LM90_STATUS_BUSY	(1 << 7) /* conversion is ongoing */
204 
205 #define MAX6696_STATUS2_R2THRM	(1 << 1) /* remote2 THERM limit tripped */
206 #define MAX6696_STATUS2_R2OPEN	(1 << 2) /* remote2 is an open circuit */
207 #define MAX6696_STATUS2_R2LOW	(1 << 3) /* remote2 low temp limit tripped */
208 #define MAX6696_STATUS2_R2HIGH	(1 << 4) /* remote2 high temp limit tripped */
209 #define MAX6696_STATUS2_ROT2	(1 << 5) /* remote emergency limit tripped */
210 #define MAX6696_STATUS2_R2OT2	(1 << 6) /* remote2 emergency limit tripped */
211 #define MAX6696_STATUS2_LOT2	(1 << 7) /* local emergency limit tripped */
212 
213 /*
214  * Driver data (common to all clients)
215  */
216 
217 static const struct i2c_device_id lm90_id[] = {
218 	{ "adm1032", adm1032 },
219 	{ "adt7461", adt7461 },
220 	{ "adt7461a", adt7461 },
221 	{ "g781", g781 },
222 	{ "lm90", lm90 },
223 	{ "lm86", lm86 },
224 	{ "lm89", lm86 },
225 	{ "lm99", lm99 },
226 	{ "max6646", max6646 },
227 	{ "max6647", max6646 },
228 	{ "max6649", max6646 },
229 	{ "max6654", max6654 },
230 	{ "max6657", max6657 },
231 	{ "max6658", max6657 },
232 	{ "max6659", max6659 },
233 	{ "max6680", max6680 },
234 	{ "max6681", max6680 },
235 	{ "max6695", max6696 },
236 	{ "max6696", max6696 },
237 	{ "nct1008", adt7461 },
238 	{ "w83l771", w83l771 },
239 	{ "sa56004", sa56004 },
240 	{ "tmp451", tmp451 },
241 	{ "tmp461", tmp461 },
242 	{ }
243 };
244 MODULE_DEVICE_TABLE(i2c, lm90_id);
245 
246 static const struct of_device_id __maybe_unused lm90_of_match[] = {
247 	{
248 		.compatible = "adi,adm1032",
249 		.data = (void *)adm1032
250 	},
251 	{
252 		.compatible = "adi,adt7461",
253 		.data = (void *)adt7461
254 	},
255 	{
256 		.compatible = "adi,adt7461a",
257 		.data = (void *)adt7461
258 	},
259 	{
260 		.compatible = "gmt,g781",
261 		.data = (void *)g781
262 	},
263 	{
264 		.compatible = "national,lm90",
265 		.data = (void *)lm90
266 	},
267 	{
268 		.compatible = "national,lm86",
269 		.data = (void *)lm86
270 	},
271 	{
272 		.compatible = "national,lm89",
273 		.data = (void *)lm86
274 	},
275 	{
276 		.compatible = "national,lm99",
277 		.data = (void *)lm99
278 	},
279 	{
280 		.compatible = "dallas,max6646",
281 		.data = (void *)max6646
282 	},
283 	{
284 		.compatible = "dallas,max6647",
285 		.data = (void *)max6646
286 	},
287 	{
288 		.compatible = "dallas,max6649",
289 		.data = (void *)max6646
290 	},
291 	{
292 		.compatible = "dallas,max6654",
293 		.data = (void *)max6654
294 	},
295 	{
296 		.compatible = "dallas,max6657",
297 		.data = (void *)max6657
298 	},
299 	{
300 		.compatible = "dallas,max6658",
301 		.data = (void *)max6657
302 	},
303 	{
304 		.compatible = "dallas,max6659",
305 		.data = (void *)max6659
306 	},
307 	{
308 		.compatible = "dallas,max6680",
309 		.data = (void *)max6680
310 	},
311 	{
312 		.compatible = "dallas,max6681",
313 		.data = (void *)max6680
314 	},
315 	{
316 		.compatible = "dallas,max6695",
317 		.data = (void *)max6696
318 	},
319 	{
320 		.compatible = "dallas,max6696",
321 		.data = (void *)max6696
322 	},
323 	{
324 		.compatible = "onnn,nct1008",
325 		.data = (void *)adt7461
326 	},
327 	{
328 		.compatible = "winbond,w83l771",
329 		.data = (void *)w83l771
330 	},
331 	{
332 		.compatible = "nxp,sa56004",
333 		.data = (void *)sa56004
334 	},
335 	{
336 		.compatible = "ti,tmp451",
337 		.data = (void *)tmp451
338 	},
339 	{
340 		.compatible = "ti,tmp461",
341 		.data = (void *)tmp461
342 	},
343 	{ },
344 };
345 MODULE_DEVICE_TABLE(of, lm90_of_match);
346 
347 /*
348  * chip type specific parameters
349  */
350 struct lm90_params {
351 	u32 flags;		/* Capabilities */
352 	u16 alert_alarms;	/* Which alarm bits trigger ALERT# */
353 				/* Upper 8 bits for max6695/96 */
354 	u8 max_convrate;	/* Maximum conversion rate register value */
355 	u8 reg_local_ext;	/* Extended local temp register (optional) */
356 };
357 
358 static const struct lm90_params lm90_params[] = {
359 	[adm1032] = {
360 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
361 		  | LM90_HAVE_BROKEN_ALERT | LM90_HAVE_CRIT,
362 		.alert_alarms = 0x7c,
363 		.max_convrate = 10,
364 	},
365 	[adt7461] = {
366 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
367 		  | LM90_HAVE_BROKEN_ALERT | LM90_HAVE_EXTENDED_TEMP
368 		  | LM90_HAVE_CRIT,
369 		.alert_alarms = 0x7c,
370 		.max_convrate = 10,
371 	},
372 	[g781] = {
373 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
374 		  | LM90_HAVE_BROKEN_ALERT | LM90_HAVE_CRIT,
375 		.alert_alarms = 0x7c,
376 		.max_convrate = 8,
377 	},
378 	[lm86] = {
379 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
380 		  | LM90_HAVE_CRIT,
381 		.alert_alarms = 0x7b,
382 		.max_convrate = 9,
383 	},
384 	[lm90] = {
385 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
386 		  | LM90_HAVE_CRIT,
387 		.alert_alarms = 0x7b,
388 		.max_convrate = 9,
389 	},
390 	[lm99] = {
391 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
392 		  | LM90_HAVE_CRIT,
393 		.alert_alarms = 0x7b,
394 		.max_convrate = 9,
395 	},
396 	[max6646] = {
397 		.flags = LM90_HAVE_CRIT,
398 		.alert_alarms = 0x7c,
399 		.max_convrate = 6,
400 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
401 	},
402 	[max6654] = {
403 		.alert_alarms = 0x7c,
404 		.max_convrate = 7,
405 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
406 	},
407 	[max6657] = {
408 		.flags = LM90_PAUSE_FOR_CONFIG | LM90_HAVE_CRIT,
409 		.alert_alarms = 0x7c,
410 		.max_convrate = 8,
411 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
412 	},
413 	[max6659] = {
414 		.flags = LM90_HAVE_EMERGENCY | LM90_HAVE_CRIT,
415 		.alert_alarms = 0x7c,
416 		.max_convrate = 8,
417 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
418 	},
419 	[max6680] = {
420 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_CRIT
421 		  | LM90_HAVE_CRIT_ALRM_SWP,
422 		.alert_alarms = 0x7c,
423 		.max_convrate = 7,
424 	},
425 	[max6696] = {
426 		.flags = LM90_HAVE_EMERGENCY
427 		  | LM90_HAVE_EMERGENCY_ALARM | LM90_HAVE_TEMP3 | LM90_HAVE_CRIT,
428 		.alert_alarms = 0x1c7c,
429 		.max_convrate = 6,
430 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
431 	},
432 	[w83l771] = {
433 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT | LM90_HAVE_CRIT,
434 		.alert_alarms = 0x7c,
435 		.max_convrate = 8,
436 	},
437 	[sa56004] = {
438 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT | LM90_HAVE_CRIT,
439 		.alert_alarms = 0x7b,
440 		.max_convrate = 9,
441 		.reg_local_ext = SA56004_REG_R_LOCAL_TEMPL,
442 	},
443 	[tmp451] = {
444 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
445 		  | LM90_HAVE_BROKEN_ALERT | LM90_HAVE_EXTENDED_TEMP | LM90_HAVE_CRIT,
446 		.alert_alarms = 0x7c,
447 		.max_convrate = 9,
448 		.reg_local_ext = TMP451_REG_R_LOCAL_TEMPL,
449 	},
450 	[tmp461] = {
451 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
452 		  | LM90_HAVE_BROKEN_ALERT | LM90_HAVE_EXTENDED_TEMP | LM90_HAVE_CRIT,
453 		.alert_alarms = 0x7c,
454 		.max_convrate = 9,
455 		.reg_local_ext = TMP451_REG_R_LOCAL_TEMPL,
456 	},
457 };
458 
459 /*
460  * TEMP8 register index
461  */
462 enum lm90_temp8_reg_index {
463 	LOCAL_LOW = 0,
464 	LOCAL_HIGH,
465 	LOCAL_CRIT,
466 	REMOTE_CRIT,
467 	LOCAL_EMERG,	/* max6659 and max6695/96 */
468 	REMOTE_EMERG,	/* max6659 and max6695/96 */
469 	REMOTE2_CRIT,	/* max6695/96 only */
470 	REMOTE2_EMERG,	/* max6695/96 only */
471 	TEMP8_REG_NUM
472 };
473 
474 /*
475  * TEMP11 register index
476  */
477 enum lm90_temp11_reg_index {
478 	REMOTE_TEMP = 0,
479 	REMOTE_LOW,
480 	REMOTE_HIGH,
481 	REMOTE_OFFSET,	/* except max6646, max6657/58/59, and max6695/96 */
482 	LOCAL_TEMP,
483 	REMOTE2_TEMP,	/* max6695/96 only */
484 	REMOTE2_LOW,	/* max6695/96 only */
485 	REMOTE2_HIGH,	/* max6695/96 only */
486 	TEMP11_REG_NUM
487 };
488 
489 /*
490  * Client data (each client gets its own)
491  */
492 
493 struct lm90_data {
494 	struct i2c_client *client;
495 	struct device *hwmon_dev;
496 	u32 channel_config[4];
497 	struct hwmon_channel_info temp_info;
498 	const struct hwmon_channel_info *info[3];
499 	struct hwmon_chip_info chip;
500 	struct mutex update_lock;
501 	bool valid;		/* true if register values are valid */
502 	unsigned long last_updated; /* in jiffies */
503 	int kind;
504 	u32 flags;
505 
506 	unsigned int update_interval; /* in milliseconds */
507 
508 	u8 config;		/* Current configuration register value */
509 	u8 config_orig;		/* Original configuration register value */
510 	u8 convrate_orig;	/* Original conversion rate register value */
511 	u16 alert_alarms;	/* Which alarm bits trigger ALERT# */
512 				/* Upper 8 bits for max6695/96 */
513 	u8 max_convrate;	/* Maximum conversion rate */
514 	u8 reg_local_ext;	/* local extension register offset */
515 
516 	/* registers values */
517 	s8 temp8[TEMP8_REG_NUM];
518 	s16 temp11[TEMP11_REG_NUM];
519 	u8 temp_hyst;
520 	u16 alarms; /* bitvector (upper 8 bits for max6695/96) */
521 };
522 
523 /*
524  * Support functions
525  */
526 
527 /*
528  * The ADM1032 supports PEC but not on write byte transactions, so we need
529  * to explicitly ask for a transaction without PEC.
530  */
531 static inline s32 adm1032_write_byte(struct i2c_client *client, u8 value)
532 {
533 	return i2c_smbus_xfer(client->adapter, client->addr,
534 			      client->flags & ~I2C_CLIENT_PEC,
535 			      I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL);
536 }
537 
538 /*
539  * It is assumed that client->update_lock is held (unless we are in
540  * detection or initialization steps). This matters when PEC is enabled,
541  * because we don't want the address pointer to change between the write
542  * byte and the read byte transactions.
543  */
544 static int lm90_read_reg(struct i2c_client *client, u8 reg)
545 {
546 	int err;
547 
548 	if (client->flags & I2C_CLIENT_PEC) {
549 		err = adm1032_write_byte(client, reg);
550 		if (err >= 0)
551 			err = i2c_smbus_read_byte(client);
552 	} else
553 		err = i2c_smbus_read_byte_data(client, reg);
554 
555 	return err;
556 }
557 
558 static int lm90_read16(struct i2c_client *client, u8 regh, u8 regl)
559 {
560 	int oldh, newh, l;
561 
562 	/*
563 	 * There is a trick here. We have to read two registers to have the
564 	 * sensor temperature, but we have to beware a conversion could occur
565 	 * between the readings. The datasheet says we should either use
566 	 * the one-shot conversion register, which we don't want to do
567 	 * (disables hardware monitoring) or monitor the busy bit, which is
568 	 * impossible (we can't read the values and monitor that bit at the
569 	 * exact same time). So the solution used here is to read the high
570 	 * byte once, then the low byte, then the high byte again. If the new
571 	 * high byte matches the old one, then we have a valid reading. Else
572 	 * we have to read the low byte again, and now we believe we have a
573 	 * correct reading.
574 	 */
575 	oldh = lm90_read_reg(client, regh);
576 	if (oldh < 0)
577 		return oldh;
578 	l = lm90_read_reg(client, regl);
579 	if (l < 0)
580 		return l;
581 	newh = lm90_read_reg(client, regh);
582 	if (newh < 0)
583 		return newh;
584 	if (oldh != newh) {
585 		l = lm90_read_reg(client, regl);
586 		if (l < 0)
587 			return l;
588 	}
589 	return (newh << 8) | l;
590 }
591 
592 static int lm90_update_confreg(struct lm90_data *data, u8 config)
593 {
594 	if (data->config != config) {
595 		int err;
596 
597 		err = i2c_smbus_write_byte_data(data->client,
598 						LM90_REG_W_CONFIG1,
599 						config);
600 		if (err)
601 			return err;
602 		data->config = config;
603 	}
604 	return 0;
605 }
606 
607 /*
608  * client->update_lock must be held when calling this function (unless we are
609  * in detection or initialization steps), and while a remote channel other
610  * than channel 0 is selected. Also, calling code must make sure to re-select
611  * external channel 0 before releasing the lock. This is necessary because
612  * various registers have different meanings as a result of selecting a
613  * non-default remote channel.
614  */
615 static int lm90_select_remote_channel(struct lm90_data *data, int channel)
616 {
617 	int err = 0;
618 
619 	if (data->kind == max6696) {
620 		u8 config = data->config & ~0x08;
621 
622 		if (channel)
623 			config |= 0x08;
624 		err = lm90_update_confreg(data, config);
625 	}
626 	return err;
627 }
628 
629 static int lm90_write_convrate(struct lm90_data *data, int val)
630 {
631 	u8 config = data->config;
632 	int err;
633 
634 	/* Save config and pause conversion */
635 	if (data->flags & LM90_PAUSE_FOR_CONFIG) {
636 		err = lm90_update_confreg(data, config | 0x40);
637 		if (err < 0)
638 			return err;
639 	}
640 
641 	/* Set conv rate */
642 	err = i2c_smbus_write_byte_data(data->client, LM90_REG_W_CONVRATE, val);
643 
644 	/* Revert change to config */
645 	lm90_update_confreg(data, config);
646 
647 	return err;
648 }
649 
650 /*
651  * Set conversion rate.
652  * client->update_lock must be held when calling this function (unless we are
653  * in detection or initialization steps).
654  */
655 static int lm90_set_convrate(struct i2c_client *client, struct lm90_data *data,
656 			     unsigned int interval)
657 {
658 	unsigned int update_interval;
659 	int i, err;
660 
661 	/* Shift calculations to avoid rounding errors */
662 	interval <<= 6;
663 
664 	/* find the nearest update rate */
665 	for (i = 0, update_interval = LM90_MAX_CONVRATE_MS << 6;
666 	     i < data->max_convrate; i++, update_interval >>= 1)
667 		if (interval >= update_interval * 3 / 4)
668 			break;
669 
670 	err = lm90_write_convrate(data, i);
671 	data->update_interval = DIV_ROUND_CLOSEST(update_interval, 64);
672 	return err;
673 }
674 
675 static int lm90_update_limits(struct device *dev)
676 {
677 	struct lm90_data *data = dev_get_drvdata(dev);
678 	struct i2c_client *client = data->client;
679 	int val;
680 
681 	if (data->flags & LM90_HAVE_CRIT) {
682 		val = lm90_read_reg(client, LM90_REG_R_LOCAL_CRIT);
683 		if (val < 0)
684 			return val;
685 		data->temp8[LOCAL_CRIT] = val;
686 
687 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT);
688 		if (val < 0)
689 			return val;
690 		data->temp8[REMOTE_CRIT] = val;
691 
692 		val = lm90_read_reg(client, LM90_REG_R_TCRIT_HYST);
693 		if (val < 0)
694 			return val;
695 		data->temp_hyst = val;
696 	}
697 
698 	val = lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH);
699 	if (val < 0)
700 		return val;
701 	data->temp11[REMOTE_LOW] = val << 8;
702 
703 	if (data->flags & LM90_HAVE_REM_LIMIT_EXT) {
704 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_LOWL);
705 		if (val < 0)
706 			return val;
707 		data->temp11[REMOTE_LOW] |= val;
708 	}
709 
710 	val = lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH);
711 	if (val < 0)
712 		return val;
713 	data->temp11[REMOTE_HIGH] = val << 8;
714 
715 	if (data->flags & LM90_HAVE_REM_LIMIT_EXT) {
716 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHL);
717 		if (val < 0)
718 			return val;
719 		data->temp11[REMOTE_HIGH] |= val;
720 	}
721 
722 	if (data->flags & LM90_HAVE_OFFSET) {
723 		val = lm90_read16(client, LM90_REG_R_REMOTE_OFFSH,
724 				  LM90_REG_R_REMOTE_OFFSL);
725 		if (val < 0)
726 			return val;
727 		data->temp11[REMOTE_OFFSET] = val;
728 	}
729 
730 	if (data->flags & LM90_HAVE_EMERGENCY) {
731 		val = lm90_read_reg(client, MAX6659_REG_R_LOCAL_EMERG);
732 		if (val < 0)
733 			return val;
734 		data->temp8[LOCAL_EMERG] = val;
735 
736 		val = lm90_read_reg(client, MAX6659_REG_R_REMOTE_EMERG);
737 		if (val < 0)
738 			return val;
739 		data->temp8[REMOTE_EMERG] = val;
740 	}
741 
742 	if (data->kind == max6696) {
743 		val = lm90_select_remote_channel(data, 1);
744 		if (val < 0)
745 			return val;
746 
747 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_CRIT);
748 		if (val < 0)
749 			return val;
750 		data->temp8[REMOTE2_CRIT] = val;
751 
752 		val = lm90_read_reg(client, MAX6659_REG_R_REMOTE_EMERG);
753 		if (val < 0)
754 			return val;
755 		data->temp8[REMOTE2_EMERG] = val;
756 
757 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_LOWH);
758 		if (val < 0)
759 			return val;
760 		data->temp11[REMOTE2_LOW] = val << 8;
761 
762 		val = lm90_read_reg(client, LM90_REG_R_REMOTE_HIGHH);
763 		if (val < 0)
764 			return val;
765 		data->temp11[REMOTE2_HIGH] = val << 8;
766 
767 		lm90_select_remote_channel(data, 0);
768 	}
769 
770 	return 0;
771 }
772 
773 static int lm90_update_device(struct device *dev)
774 {
775 	struct lm90_data *data = dev_get_drvdata(dev);
776 	struct i2c_client *client = data->client;
777 	unsigned long next_update;
778 	int val;
779 
780 	if (!data->valid) {
781 		val = lm90_update_limits(dev);
782 		if (val < 0)
783 			return val;
784 	}
785 
786 	next_update = data->last_updated +
787 		      msecs_to_jiffies(data->update_interval);
788 	if (time_after(jiffies, next_update) || !data->valid) {
789 		dev_dbg(&client->dev, "Updating lm90 data.\n");
790 
791 		data->valid = false;
792 
793 		val = lm90_read_reg(client, LM90_REG_R_LOCAL_LOW);
794 		if (val < 0)
795 			return val;
796 		data->temp8[LOCAL_LOW] = val;
797 
798 		val = lm90_read_reg(client, LM90_REG_R_LOCAL_HIGH);
799 		if (val < 0)
800 			return val;
801 		data->temp8[LOCAL_HIGH] = val;
802 
803 		if (data->reg_local_ext) {
804 			val = lm90_read16(client, LM90_REG_R_LOCAL_TEMP,
805 					  data->reg_local_ext);
806 			if (val < 0)
807 				return val;
808 			data->temp11[LOCAL_TEMP] = val;
809 		} else {
810 			val = lm90_read_reg(client, LM90_REG_R_LOCAL_TEMP);
811 			if (val < 0)
812 				return val;
813 			data->temp11[LOCAL_TEMP] = val << 8;
814 		}
815 		val = lm90_read16(client, LM90_REG_R_REMOTE_TEMPH,
816 				  LM90_REG_R_REMOTE_TEMPL);
817 		if (val < 0)
818 			return val;
819 		data->temp11[REMOTE_TEMP] = val;
820 
821 		val = lm90_read_reg(client, LM90_REG_R_STATUS);
822 		if (val < 0)
823 			return val;
824 		data->alarms = val & ~LM90_STATUS_BUSY;
825 
826 		if (data->kind == max6696) {
827 			val = lm90_select_remote_channel(data, 1);
828 			if (val < 0)
829 				return val;
830 
831 			val = lm90_read16(client, LM90_REG_R_REMOTE_TEMPH,
832 					  LM90_REG_R_REMOTE_TEMPL);
833 			if (val < 0) {
834 				lm90_select_remote_channel(data, 0);
835 				return val;
836 			}
837 			data->temp11[REMOTE2_TEMP] = val;
838 
839 			lm90_select_remote_channel(data, 0);
840 
841 			val = lm90_read_reg(client, MAX6696_REG_R_STATUS2);
842 			if (val < 0)
843 				return val;
844 			data->alarms |= val << 8;
845 		}
846 
847 		/*
848 		 * Re-enable ALERT# output if it was originally enabled and
849 		 * relevant alarms are all clear
850 		 */
851 		if (!(data->config_orig & 0x80) &&
852 		    !(data->alarms & data->alert_alarms)) {
853 			if (data->config & 0x80) {
854 				dev_dbg(&client->dev, "Re-enabling ALERT#\n");
855 				lm90_update_confreg(data, data->config & ~0x80);
856 			}
857 		}
858 
859 		data->last_updated = jiffies;
860 		data->valid = true;
861 	}
862 
863 	return 0;
864 }
865 
866 /*
867  * Conversions
868  * For local temperatures and limits, critical limits and the hysteresis
869  * value, the LM90 uses signed 8-bit values with LSB = 1 degree Celsius.
870  * For remote temperatures and limits, it uses signed 11-bit values with
871  * LSB = 0.125 degree Celsius, left-justified in 16-bit registers.  Some
872  * Maxim chips use unsigned values.
873  */
874 
875 static inline int temp_from_s8(s8 val)
876 {
877 	return val * 1000;
878 }
879 
880 static inline int temp_from_u8(u8 val)
881 {
882 	return val * 1000;
883 }
884 
885 static inline int temp_from_s16(s16 val)
886 {
887 	return val / 32 * 125;
888 }
889 
890 static inline int temp_from_u16(u16 val)
891 {
892 	return val / 32 * 125;
893 }
894 
895 static s8 temp_to_s8(long val)
896 {
897 	if (val <= -128000)
898 		return -128;
899 	if (val >= 127000)
900 		return 127;
901 	if (val < 0)
902 		return (val - 500) / 1000;
903 	return (val + 500) / 1000;
904 }
905 
906 static u8 temp_to_u8(long val)
907 {
908 	if (val <= 0)
909 		return 0;
910 	if (val >= 255000)
911 		return 255;
912 	return (val + 500) / 1000;
913 }
914 
915 static s16 temp_to_s16(long val)
916 {
917 	if (val <= -128000)
918 		return 0x8000;
919 	if (val >= 127875)
920 		return 0x7FE0;
921 	if (val < 0)
922 		return (val - 62) / 125 * 32;
923 	return (val + 62) / 125 * 32;
924 }
925 
926 static u8 hyst_to_reg(long val)
927 {
928 	if (val <= 0)
929 		return 0;
930 	if (val >= 30500)
931 		return 31;
932 	return (val + 500) / 1000;
933 }
934 
935 /*
936  * ADT7461 in compatibility mode is almost identical to LM90 except that
937  * attempts to write values that are outside the range 0 < temp < 127 are
938  * treated as the boundary value.
939  *
940  * ADT7461 in "extended mode" operation uses unsigned integers offset by
941  * 64 (e.g., 0 -> -64 degC).  The range is restricted to -64..191 degC.
942  */
943 static inline int temp_from_u8_adt7461(struct lm90_data *data, u8 val)
944 {
945 	if (data->flags & LM90_FLAG_ADT7461_EXT)
946 		return (val - 64) * 1000;
947 	return temp_from_s8(val);
948 }
949 
950 static inline int temp_from_u16_adt7461(struct lm90_data *data, u16 val)
951 {
952 	if (data->flags & LM90_FLAG_ADT7461_EXT)
953 		return (val - 0x4000) / 64 * 250;
954 	return temp_from_s16(val);
955 }
956 
957 static u8 temp_to_u8_adt7461(struct lm90_data *data, long val)
958 {
959 	if (data->flags & LM90_FLAG_ADT7461_EXT) {
960 		if (val <= -64000)
961 			return 0;
962 		if (val >= 191000)
963 			return 0xFF;
964 		return (val + 500 + 64000) / 1000;
965 	}
966 	if (val <= 0)
967 		return 0;
968 	if (val >= 127000)
969 		return 127;
970 	return (val + 500) / 1000;
971 }
972 
973 static u16 temp_to_u16_adt7461(struct lm90_data *data, long val)
974 {
975 	if (data->flags & LM90_FLAG_ADT7461_EXT) {
976 		if (val <= -64000)
977 			return 0;
978 		if (val >= 191750)
979 			return 0xFFC0;
980 		return (val + 64000 + 125) / 250 * 64;
981 	}
982 	if (val <= 0)
983 		return 0;
984 	if (val >= 127750)
985 		return 0x7FC0;
986 	return (val + 125) / 250 * 64;
987 }
988 
989 /* pec used for ADM1032 only */
990 static ssize_t pec_show(struct device *dev, struct device_attribute *dummy,
991 			char *buf)
992 {
993 	struct i2c_client *client = to_i2c_client(dev);
994 
995 	return sprintf(buf, "%d\n", !!(client->flags & I2C_CLIENT_PEC));
996 }
997 
998 static ssize_t pec_store(struct device *dev, struct device_attribute *dummy,
999 			 const char *buf, size_t count)
1000 {
1001 	struct i2c_client *client = to_i2c_client(dev);
1002 	long val;
1003 	int err;
1004 
1005 	err = kstrtol(buf, 10, &val);
1006 	if (err < 0)
1007 		return err;
1008 
1009 	switch (val) {
1010 	case 0:
1011 		client->flags &= ~I2C_CLIENT_PEC;
1012 		break;
1013 	case 1:
1014 		client->flags |= I2C_CLIENT_PEC;
1015 		break;
1016 	default:
1017 		return -EINVAL;
1018 	}
1019 
1020 	return count;
1021 }
1022 
1023 static DEVICE_ATTR_RW(pec);
1024 
1025 static int lm90_get_temp11(struct lm90_data *data, int index)
1026 {
1027 	s16 temp11 = data->temp11[index];
1028 	int temp;
1029 
1030 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1031 		temp = temp_from_u16_adt7461(data, temp11);
1032 	else if (data->kind == max6646)
1033 		temp = temp_from_u16(temp11);
1034 	else
1035 		temp = temp_from_s16(temp11);
1036 
1037 	/* +16 degrees offset for temp2 for the LM99 */
1038 	if (data->kind == lm99 && index <= 2)
1039 		temp += 16000;
1040 
1041 	return temp;
1042 }
1043 
1044 static int lm90_set_temp11(struct lm90_data *data, int index, long val)
1045 {
1046 	static struct reg {
1047 		u8 high;
1048 		u8 low;
1049 	} reg[] = {
1050 	[REMOTE_LOW] = { LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL },
1051 	[REMOTE_HIGH] = { LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL },
1052 	[REMOTE_OFFSET] = { LM90_REG_W_REMOTE_OFFSH, LM90_REG_W_REMOTE_OFFSL },
1053 	[REMOTE2_LOW] = { LM90_REG_W_REMOTE_LOWH, LM90_REG_W_REMOTE_LOWL },
1054 	[REMOTE2_HIGH] = { LM90_REG_W_REMOTE_HIGHH, LM90_REG_W_REMOTE_HIGHL }
1055 	};
1056 	struct i2c_client *client = data->client;
1057 	struct reg *regp = &reg[index];
1058 	int err;
1059 
1060 	/* +16 degrees offset for temp2 for the LM99 */
1061 	if (data->kind == lm99 && index <= 2) {
1062 		/* prevent integer underflow */
1063 		val = max(val, -128000l);
1064 		val -= 16000;
1065 	}
1066 
1067 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1068 		data->temp11[index] = temp_to_u16_adt7461(data, val);
1069 	else if (data->kind == max6646)
1070 		data->temp11[index] = temp_to_u8(val) << 8;
1071 	else if (data->flags & LM90_HAVE_REM_LIMIT_EXT)
1072 		data->temp11[index] = temp_to_s16(val);
1073 	else
1074 		data->temp11[index] = temp_to_s8(val) << 8;
1075 
1076 	lm90_select_remote_channel(data, index >= 3);
1077 	err = i2c_smbus_write_byte_data(client, regp->high,
1078 				  data->temp11[index] >> 8);
1079 	if (err < 0)
1080 		return err;
1081 	if (data->flags & LM90_HAVE_REM_LIMIT_EXT)
1082 		err = i2c_smbus_write_byte_data(client, regp->low,
1083 						data->temp11[index] & 0xff);
1084 
1085 	lm90_select_remote_channel(data, 0);
1086 	return err;
1087 }
1088 
1089 static int lm90_get_temp8(struct lm90_data *data, int index)
1090 {
1091 	s8 temp8 = data->temp8[index];
1092 	int temp;
1093 
1094 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1095 		temp = temp_from_u8_adt7461(data, temp8);
1096 	else if (data->kind == max6646)
1097 		temp = temp_from_u8(temp8);
1098 	else
1099 		temp = temp_from_s8(temp8);
1100 
1101 	/* +16 degrees offset for temp2 for the LM99 */
1102 	if (data->kind == lm99 && index == 3)
1103 		temp += 16000;
1104 
1105 	return temp;
1106 }
1107 
1108 static int lm90_set_temp8(struct lm90_data *data, int index, long val)
1109 {
1110 	static const u8 reg[TEMP8_REG_NUM] = {
1111 		LM90_REG_W_LOCAL_LOW,
1112 		LM90_REG_W_LOCAL_HIGH,
1113 		LM90_REG_W_LOCAL_CRIT,
1114 		LM90_REG_W_REMOTE_CRIT,
1115 		MAX6659_REG_W_LOCAL_EMERG,
1116 		MAX6659_REG_W_REMOTE_EMERG,
1117 		LM90_REG_W_REMOTE_CRIT,
1118 		MAX6659_REG_W_REMOTE_EMERG,
1119 	};
1120 	struct i2c_client *client = data->client;
1121 	int err;
1122 
1123 	/* +16 degrees offset for temp2 for the LM99 */
1124 	if (data->kind == lm99 && index == 3) {
1125 		/* prevent integer underflow */
1126 		val = max(val, -128000l);
1127 		val -= 16000;
1128 	}
1129 
1130 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1131 		data->temp8[index] = temp_to_u8_adt7461(data, val);
1132 	else if (data->kind == max6646)
1133 		data->temp8[index] = temp_to_u8(val);
1134 	else
1135 		data->temp8[index] = temp_to_s8(val);
1136 
1137 	lm90_select_remote_channel(data, index >= 6);
1138 	err = i2c_smbus_write_byte_data(client, reg[index], data->temp8[index]);
1139 	lm90_select_remote_channel(data, 0);
1140 
1141 	return err;
1142 }
1143 
1144 static int lm90_get_temphyst(struct lm90_data *data, int index)
1145 {
1146 	int temp;
1147 
1148 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1149 		temp = temp_from_u8_adt7461(data, data->temp8[index]);
1150 	else if (data->kind == max6646)
1151 		temp = temp_from_u8(data->temp8[index]);
1152 	else
1153 		temp = temp_from_s8(data->temp8[index]);
1154 
1155 	/* +16 degrees offset for temp2 for the LM99 */
1156 	if (data->kind == lm99 && index == 3)
1157 		temp += 16000;
1158 
1159 	return temp - temp_from_s8(data->temp_hyst);
1160 }
1161 
1162 static int lm90_set_temphyst(struct lm90_data *data, long val)
1163 {
1164 	struct i2c_client *client = data->client;
1165 	int temp;
1166 	int err;
1167 
1168 	if (data->flags & LM90_HAVE_EXTENDED_TEMP)
1169 		temp = temp_from_u8_adt7461(data, data->temp8[LOCAL_CRIT]);
1170 	else if (data->kind == max6646)
1171 		temp = temp_from_u8(data->temp8[LOCAL_CRIT]);
1172 	else
1173 		temp = temp_from_s8(data->temp8[LOCAL_CRIT]);
1174 
1175 	/* prevent integer overflow/underflow */
1176 	val = clamp_val(val, -128000l, 255000l);
1177 
1178 	data->temp_hyst = hyst_to_reg(temp - val);
1179 	err = i2c_smbus_write_byte_data(client, LM90_REG_W_TCRIT_HYST,
1180 					data->temp_hyst);
1181 	return err;
1182 }
1183 
1184 static const u8 lm90_temp_index[3] = {
1185 	LOCAL_TEMP, REMOTE_TEMP, REMOTE2_TEMP
1186 };
1187 
1188 static const u8 lm90_temp_min_index[3] = {
1189 	LOCAL_LOW, REMOTE_LOW, REMOTE2_LOW
1190 };
1191 
1192 static const u8 lm90_temp_max_index[3] = {
1193 	LOCAL_HIGH, REMOTE_HIGH, REMOTE2_HIGH
1194 };
1195 
1196 static const u8 lm90_temp_crit_index[3] = {
1197 	LOCAL_CRIT, REMOTE_CRIT, REMOTE2_CRIT
1198 };
1199 
1200 static const u8 lm90_temp_emerg_index[3] = {
1201 	LOCAL_EMERG, REMOTE_EMERG, REMOTE2_EMERG
1202 };
1203 
1204 static const u8 lm90_min_alarm_bits[3] = { 5, 3, 11 };
1205 static const u8 lm90_max_alarm_bits[3] = { 6, 4, 12 };
1206 static const u8 lm90_crit_alarm_bits[3] = { 0, 1, 9 };
1207 static const u8 lm90_crit_alarm_bits_swapped[3] = { 1, 0, 9 };
1208 static const u8 lm90_emergency_alarm_bits[3] = { 15, 13, 14 };
1209 static const u8 lm90_fault_bits[3] = { 0, 2, 10 };
1210 
1211 static int lm90_temp_read(struct device *dev, u32 attr, int channel, long *val)
1212 {
1213 	struct lm90_data *data = dev_get_drvdata(dev);
1214 	int err;
1215 
1216 	mutex_lock(&data->update_lock);
1217 	err = lm90_update_device(dev);
1218 	mutex_unlock(&data->update_lock);
1219 	if (err)
1220 		return err;
1221 
1222 	switch (attr) {
1223 	case hwmon_temp_input:
1224 		*val = lm90_get_temp11(data, lm90_temp_index[channel]);
1225 		break;
1226 	case hwmon_temp_min_alarm:
1227 		*val = (data->alarms >> lm90_min_alarm_bits[channel]) & 1;
1228 		break;
1229 	case hwmon_temp_max_alarm:
1230 		*val = (data->alarms >> lm90_max_alarm_bits[channel]) & 1;
1231 		break;
1232 	case hwmon_temp_crit_alarm:
1233 		if (data->flags & LM90_HAVE_CRIT_ALRM_SWP)
1234 			*val = (data->alarms >> lm90_crit_alarm_bits_swapped[channel]) & 1;
1235 		else
1236 			*val = (data->alarms >> lm90_crit_alarm_bits[channel]) & 1;
1237 		break;
1238 	case hwmon_temp_emergency_alarm:
1239 		*val = (data->alarms >> lm90_emergency_alarm_bits[channel]) & 1;
1240 		break;
1241 	case hwmon_temp_fault:
1242 		*val = (data->alarms >> lm90_fault_bits[channel]) & 1;
1243 		break;
1244 	case hwmon_temp_min:
1245 		if (channel == 0)
1246 			*val = lm90_get_temp8(data,
1247 					      lm90_temp_min_index[channel]);
1248 		else
1249 			*val = lm90_get_temp11(data,
1250 					       lm90_temp_min_index[channel]);
1251 		break;
1252 	case hwmon_temp_max:
1253 		if (channel == 0)
1254 			*val = lm90_get_temp8(data,
1255 					      lm90_temp_max_index[channel]);
1256 		else
1257 			*val = lm90_get_temp11(data,
1258 					       lm90_temp_max_index[channel]);
1259 		break;
1260 	case hwmon_temp_crit:
1261 		*val = lm90_get_temp8(data, lm90_temp_crit_index[channel]);
1262 		break;
1263 	case hwmon_temp_crit_hyst:
1264 		*val = lm90_get_temphyst(data, lm90_temp_crit_index[channel]);
1265 		break;
1266 	case hwmon_temp_emergency:
1267 		*val = lm90_get_temp8(data, lm90_temp_emerg_index[channel]);
1268 		break;
1269 	case hwmon_temp_emergency_hyst:
1270 		*val = lm90_get_temphyst(data, lm90_temp_emerg_index[channel]);
1271 		break;
1272 	case hwmon_temp_offset:
1273 		*val = lm90_get_temp11(data, REMOTE_OFFSET);
1274 		break;
1275 	default:
1276 		return -EOPNOTSUPP;
1277 	}
1278 	return 0;
1279 }
1280 
1281 static int lm90_temp_write(struct device *dev, u32 attr, int channel, long val)
1282 {
1283 	struct lm90_data *data = dev_get_drvdata(dev);
1284 	int err;
1285 
1286 	mutex_lock(&data->update_lock);
1287 
1288 	err = lm90_update_device(dev);
1289 	if (err)
1290 		goto error;
1291 
1292 	switch (attr) {
1293 	case hwmon_temp_min:
1294 		if (channel == 0)
1295 			err = lm90_set_temp8(data,
1296 					      lm90_temp_min_index[channel],
1297 					      val);
1298 		else
1299 			err = lm90_set_temp11(data,
1300 					      lm90_temp_min_index[channel],
1301 					      val);
1302 		break;
1303 	case hwmon_temp_max:
1304 		if (channel == 0)
1305 			err = lm90_set_temp8(data,
1306 					     lm90_temp_max_index[channel],
1307 					     val);
1308 		else
1309 			err = lm90_set_temp11(data,
1310 					      lm90_temp_max_index[channel],
1311 					      val);
1312 		break;
1313 	case hwmon_temp_crit:
1314 		err = lm90_set_temp8(data, lm90_temp_crit_index[channel], val);
1315 		break;
1316 	case hwmon_temp_crit_hyst:
1317 		err = lm90_set_temphyst(data, val);
1318 		break;
1319 	case hwmon_temp_emergency:
1320 		err = lm90_set_temp8(data, lm90_temp_emerg_index[channel], val);
1321 		break;
1322 	case hwmon_temp_offset:
1323 		err = lm90_set_temp11(data, REMOTE_OFFSET, val);
1324 		break;
1325 	default:
1326 		err = -EOPNOTSUPP;
1327 		break;
1328 	}
1329 error:
1330 	mutex_unlock(&data->update_lock);
1331 
1332 	return err;
1333 }
1334 
1335 static umode_t lm90_temp_is_visible(const void *data, u32 attr, int channel)
1336 {
1337 	switch (attr) {
1338 	case hwmon_temp_input:
1339 	case hwmon_temp_min_alarm:
1340 	case hwmon_temp_max_alarm:
1341 	case hwmon_temp_crit_alarm:
1342 	case hwmon_temp_emergency_alarm:
1343 	case hwmon_temp_emergency_hyst:
1344 	case hwmon_temp_fault:
1345 		return 0444;
1346 	case hwmon_temp_min:
1347 	case hwmon_temp_max:
1348 	case hwmon_temp_crit:
1349 	case hwmon_temp_emergency:
1350 	case hwmon_temp_offset:
1351 		return 0644;
1352 	case hwmon_temp_crit_hyst:
1353 		if (channel == 0)
1354 			return 0644;
1355 		return 0444;
1356 	default:
1357 		return 0;
1358 	}
1359 }
1360 
1361 static int lm90_chip_read(struct device *dev, u32 attr, int channel, long *val)
1362 {
1363 	struct lm90_data *data = dev_get_drvdata(dev);
1364 	int err;
1365 
1366 	mutex_lock(&data->update_lock);
1367 	err = lm90_update_device(dev);
1368 	mutex_unlock(&data->update_lock);
1369 	if (err)
1370 		return err;
1371 
1372 	switch (attr) {
1373 	case hwmon_chip_update_interval:
1374 		*val = data->update_interval;
1375 		break;
1376 	case hwmon_chip_alarms:
1377 		*val = data->alarms;
1378 		break;
1379 	default:
1380 		return -EOPNOTSUPP;
1381 	}
1382 
1383 	return 0;
1384 }
1385 
1386 static int lm90_chip_write(struct device *dev, u32 attr, int channel, long val)
1387 {
1388 	struct lm90_data *data = dev_get_drvdata(dev);
1389 	struct i2c_client *client = data->client;
1390 	int err;
1391 
1392 	mutex_lock(&data->update_lock);
1393 
1394 	err = lm90_update_device(dev);
1395 	if (err)
1396 		goto error;
1397 
1398 	switch (attr) {
1399 	case hwmon_chip_update_interval:
1400 		err = lm90_set_convrate(client, data,
1401 					clamp_val(val, 0, 100000));
1402 		break;
1403 	default:
1404 		err = -EOPNOTSUPP;
1405 		break;
1406 	}
1407 error:
1408 	mutex_unlock(&data->update_lock);
1409 
1410 	return err;
1411 }
1412 
1413 static umode_t lm90_chip_is_visible(const void *data, u32 attr, int channel)
1414 {
1415 	switch (attr) {
1416 	case hwmon_chip_update_interval:
1417 		return 0644;
1418 	case hwmon_chip_alarms:
1419 		return 0444;
1420 	default:
1421 		return 0;
1422 	}
1423 }
1424 
1425 static int lm90_read(struct device *dev, enum hwmon_sensor_types type,
1426 		     u32 attr, int channel, long *val)
1427 {
1428 	switch (type) {
1429 	case hwmon_chip:
1430 		return lm90_chip_read(dev, attr, channel, val);
1431 	case hwmon_temp:
1432 		return lm90_temp_read(dev, attr, channel, val);
1433 	default:
1434 		return -EOPNOTSUPP;
1435 	}
1436 }
1437 
1438 static int lm90_write(struct device *dev, enum hwmon_sensor_types type,
1439 		      u32 attr, int channel, long val)
1440 {
1441 	switch (type) {
1442 	case hwmon_chip:
1443 		return lm90_chip_write(dev, attr, channel, val);
1444 	case hwmon_temp:
1445 		return lm90_temp_write(dev, attr, channel, val);
1446 	default:
1447 		return -EOPNOTSUPP;
1448 	}
1449 }
1450 
1451 static umode_t lm90_is_visible(const void *data, enum hwmon_sensor_types type,
1452 			       u32 attr, int channel)
1453 {
1454 	switch (type) {
1455 	case hwmon_chip:
1456 		return lm90_chip_is_visible(data, attr, channel);
1457 	case hwmon_temp:
1458 		return lm90_temp_is_visible(data, attr, channel);
1459 	default:
1460 		return 0;
1461 	}
1462 }
1463 
1464 /* Return 0 if detection is successful, -ENODEV otherwise */
1465 static int lm90_detect(struct i2c_client *client,
1466 		       struct i2c_board_info *info)
1467 {
1468 	struct i2c_adapter *adapter = client->adapter;
1469 	int address = client->addr;
1470 	const char *name = NULL;
1471 	int man_id, chip_id, config1, config2, convrate;
1472 
1473 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
1474 		return -ENODEV;
1475 
1476 	/* detection and identification */
1477 	man_id = i2c_smbus_read_byte_data(client, LM90_REG_R_MAN_ID);
1478 	chip_id = i2c_smbus_read_byte_data(client, LM90_REG_R_CHIP_ID);
1479 	config1 = i2c_smbus_read_byte_data(client, LM90_REG_R_CONFIG1);
1480 	convrate = i2c_smbus_read_byte_data(client, LM90_REG_R_CONVRATE);
1481 	if (man_id < 0 || chip_id < 0 || config1 < 0 || convrate < 0)
1482 		return -ENODEV;
1483 
1484 	if (man_id == 0x01 || man_id == 0x5C || man_id == 0xA1) {
1485 		config2 = i2c_smbus_read_byte_data(client, LM90_REG_R_CONFIG2);
1486 		if (config2 < 0)
1487 			return -ENODEV;
1488 	}
1489 
1490 	if ((address == 0x4C || address == 0x4D)
1491 	 && man_id == 0x01) { /* National Semiconductor */
1492 		if ((config1 & 0x2A) == 0x00
1493 		 && (config2 & 0xF8) == 0x00
1494 		 && convrate <= 0x09) {
1495 			if (address == 0x4C
1496 			 && (chip_id & 0xF0) == 0x20) { /* LM90 */
1497 				name = "lm90";
1498 			} else
1499 			if ((chip_id & 0xF0) == 0x30) { /* LM89/LM99 */
1500 				name = "lm99";
1501 				dev_info(&adapter->dev,
1502 					 "Assuming LM99 chip at 0x%02x\n",
1503 					 address);
1504 				dev_info(&adapter->dev,
1505 					 "If it is an LM89, instantiate it "
1506 					 "with the new_device sysfs "
1507 					 "interface\n");
1508 			} else
1509 			if (address == 0x4C
1510 			 && (chip_id & 0xF0) == 0x10) { /* LM86 */
1511 				name = "lm86";
1512 			}
1513 		}
1514 	} else
1515 	if ((address == 0x4C || address == 0x4D)
1516 	 && man_id == 0x41) { /* Analog Devices */
1517 		if ((chip_id & 0xF0) == 0x40 /* ADM1032 */
1518 		 && (config1 & 0x3F) == 0x00
1519 		 && convrate <= 0x0A) {
1520 			name = "adm1032";
1521 			/*
1522 			 * The ADM1032 supports PEC, but only if combined
1523 			 * transactions are not used.
1524 			 */
1525 			if (i2c_check_functionality(adapter,
1526 						    I2C_FUNC_SMBUS_BYTE))
1527 				info->flags |= I2C_CLIENT_PEC;
1528 		} else
1529 		if (chip_id == 0x51 /* ADT7461 */
1530 		 && (config1 & 0x1B) == 0x00
1531 		 && convrate <= 0x0A) {
1532 			name = "adt7461";
1533 		} else
1534 		if (chip_id == 0x57 /* ADT7461A, NCT1008 */
1535 		 && (config1 & 0x1B) == 0x00
1536 		 && convrate <= 0x0A) {
1537 			name = "adt7461a";
1538 		}
1539 	} else
1540 	if (man_id == 0x4D) { /* Maxim */
1541 		int emerg, emerg2, status2;
1542 
1543 		/*
1544 		 * We read MAX6659_REG_R_REMOTE_EMERG twice, and re-read
1545 		 * LM90_REG_R_MAN_ID in between. If MAX6659_REG_R_REMOTE_EMERG
1546 		 * exists, both readings will reflect the same value. Otherwise,
1547 		 * the readings will be different.
1548 		 */
1549 		emerg = i2c_smbus_read_byte_data(client,
1550 						 MAX6659_REG_R_REMOTE_EMERG);
1551 		man_id = i2c_smbus_read_byte_data(client,
1552 						  LM90_REG_R_MAN_ID);
1553 		emerg2 = i2c_smbus_read_byte_data(client,
1554 						  MAX6659_REG_R_REMOTE_EMERG);
1555 		status2 = i2c_smbus_read_byte_data(client,
1556 						   MAX6696_REG_R_STATUS2);
1557 		if (emerg < 0 || man_id < 0 || emerg2 < 0 || status2 < 0)
1558 			return -ENODEV;
1559 
1560 		/*
1561 		 * The MAX6657, MAX6658 and MAX6659 do NOT have a chip_id
1562 		 * register. Reading from that address will return the last
1563 		 * read value, which in our case is those of the man_id
1564 		 * register. Likewise, the config1 register seems to lack a
1565 		 * low nibble, so the value will be those of the previous
1566 		 * read, so in our case those of the man_id register.
1567 		 * MAX6659 has a third set of upper temperature limit registers.
1568 		 * Those registers also return values on MAX6657 and MAX6658,
1569 		 * thus the only way to detect MAX6659 is by its address.
1570 		 * For this reason it will be mis-detected as MAX6657 if its
1571 		 * address is 0x4C.
1572 		 */
1573 		if (chip_id == man_id
1574 		 && (address == 0x4C || address == 0x4D || address == 0x4E)
1575 		 && (config1 & 0x1F) == (man_id & 0x0F)
1576 		 && convrate <= 0x09) {
1577 			if (address == 0x4C)
1578 				name = "max6657";
1579 			else
1580 				name = "max6659";
1581 		} else
1582 		/*
1583 		 * Even though MAX6695 and MAX6696 do not have a chip ID
1584 		 * register, reading it returns 0x01. Bit 4 of the config1
1585 		 * register is unused and should return zero when read. Bit 0 of
1586 		 * the status2 register is unused and should return zero when
1587 		 * read.
1588 		 *
1589 		 * MAX6695 and MAX6696 have an additional set of temperature
1590 		 * limit registers. We can detect those chips by checking if
1591 		 * one of those registers exists.
1592 		 */
1593 		if (chip_id == 0x01
1594 		 && (config1 & 0x10) == 0x00
1595 		 && (status2 & 0x01) == 0x00
1596 		 && emerg == emerg2
1597 		 && convrate <= 0x07) {
1598 			name = "max6696";
1599 		} else
1600 		/*
1601 		 * The chip_id register of the MAX6680 and MAX6681 holds the
1602 		 * revision of the chip. The lowest bit of the config1 register
1603 		 * is unused and should return zero when read, so should the
1604 		 * second to last bit of config1 (software reset).
1605 		 */
1606 		if (chip_id == 0x01
1607 		 && (config1 & 0x03) == 0x00
1608 		 && convrate <= 0x07) {
1609 			name = "max6680";
1610 		} else
1611 		/*
1612 		 * The chip_id register of the MAX6646/6647/6649 holds the
1613 		 * revision of the chip. The lowest 6 bits of the config1
1614 		 * register are unused and should return zero when read.
1615 		 */
1616 		if (chip_id == 0x59
1617 		 && (config1 & 0x3f) == 0x00
1618 		 && convrate <= 0x07) {
1619 			name = "max6646";
1620 		} else
1621 		/*
1622 		 * The chip_id of the MAX6654 holds the revision of the chip.
1623 		 * The lowest 3 bits of the config1 register are unused and
1624 		 * should return zero when read.
1625 		 */
1626 		if (chip_id == 0x08
1627 		 && (config1 & 0x07) == 0x00
1628 		 && convrate <= 0x07) {
1629 			name = "max6654";
1630 		}
1631 	} else
1632 	if (address == 0x4C
1633 	 && man_id == 0x5C) { /* Winbond/Nuvoton */
1634 		if ((config1 & 0x2A) == 0x00
1635 		 && (config2 & 0xF8) == 0x00) {
1636 			if (chip_id == 0x01 /* W83L771W/G */
1637 			 && convrate <= 0x09) {
1638 				name = "w83l771";
1639 			} else
1640 			if ((chip_id & 0xFE) == 0x10 /* W83L771AWG/ASG */
1641 			 && convrate <= 0x08) {
1642 				name = "w83l771";
1643 			}
1644 		}
1645 	} else
1646 	if (address >= 0x48 && address <= 0x4F
1647 	 && man_id == 0xA1) { /*  NXP Semiconductor/Philips */
1648 		if (chip_id == 0x00
1649 		 && (config1 & 0x2A) == 0x00
1650 		 && (config2 & 0xFE) == 0x00
1651 		 && convrate <= 0x09) {
1652 			name = "sa56004";
1653 		}
1654 	} else
1655 	if ((address == 0x4C || address == 0x4D)
1656 	 && man_id == 0x47) { /* GMT */
1657 		if (chip_id == 0x01 /* G781 */
1658 		 && (config1 & 0x3F) == 0x00
1659 		 && convrate <= 0x08)
1660 			name = "g781";
1661 	} else
1662 	if (man_id == 0x55 && chip_id == 0x00 &&
1663 	    (config1 & 0x1B) == 0x00 && convrate <= 0x09) {
1664 		int local_ext, conalert, chen, dfc;
1665 
1666 		local_ext = i2c_smbus_read_byte_data(client,
1667 						     TMP451_REG_R_LOCAL_TEMPL);
1668 		conalert = i2c_smbus_read_byte_data(client,
1669 						    TMP451_REG_CONALERT);
1670 		chen = i2c_smbus_read_byte_data(client, TMP461_REG_CHEN);
1671 		dfc = i2c_smbus_read_byte_data(client, TMP461_REG_DFC);
1672 
1673 		if ((local_ext & 0x0F) == 0x00 &&
1674 		    (conalert & 0xf1) == 0x01 &&
1675 		    (chen & 0xfc) == 0x00 &&
1676 		    (dfc & 0xfc) == 0x00) {
1677 			if (address == 0x4c && !(chen & 0x03))
1678 				name = "tmp451";
1679 			else if (address >= 0x48 && address <= 0x4f)
1680 				name = "tmp461";
1681 		}
1682 	}
1683 
1684 	if (!name) { /* identification failed */
1685 		dev_dbg(&adapter->dev,
1686 			"Unsupported chip at 0x%02x (man_id=0x%02X, "
1687 			"chip_id=0x%02X)\n", address, man_id, chip_id);
1688 		return -ENODEV;
1689 	}
1690 
1691 	strlcpy(info->type, name, I2C_NAME_SIZE);
1692 
1693 	return 0;
1694 }
1695 
1696 static void lm90_restore_conf(void *_data)
1697 {
1698 	struct lm90_data *data = _data;
1699 	struct i2c_client *client = data->client;
1700 
1701 	/* Restore initial configuration */
1702 	lm90_write_convrate(data, data->convrate_orig);
1703 	i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1,
1704 				  data->config_orig);
1705 }
1706 
1707 static int lm90_init_client(struct i2c_client *client, struct lm90_data *data)
1708 {
1709 	int config, convrate;
1710 
1711 	convrate = lm90_read_reg(client, LM90_REG_R_CONVRATE);
1712 	if (convrate < 0)
1713 		return convrate;
1714 	data->convrate_orig = convrate;
1715 
1716 	/*
1717 	 * Start the conversions.
1718 	 */
1719 	config = lm90_read_reg(client, LM90_REG_R_CONFIG1);
1720 	if (config < 0)
1721 		return config;
1722 	data->config_orig = config;
1723 	data->config = config;
1724 
1725 	lm90_set_convrate(client, data, 500); /* 500ms; 2Hz conversion rate */
1726 
1727 	/* Check Temperature Range Select */
1728 	if (data->flags & LM90_HAVE_EXTENDED_TEMP) {
1729 		if (config & 0x04)
1730 			data->flags |= LM90_FLAG_ADT7461_EXT;
1731 	}
1732 
1733 	/*
1734 	 * Put MAX6680/MAX8881 into extended resolution (bit 0x10,
1735 	 * 0.125 degree resolution) and range (0x08, extend range
1736 	 * to -64 degree) mode for the remote temperature sensor.
1737 	 */
1738 	if (data->kind == max6680)
1739 		config |= 0x18;
1740 
1741 	/*
1742 	 * Put MAX6654 into extended range (0x20, extend minimum range from
1743 	 * 0 degrees to -64 degrees). Note that extended resolution is not
1744 	 * possible on the MAX6654 unless conversion rate is set to 1 Hz or
1745 	 * slower, which is intentionally not done by default.
1746 	 */
1747 	if (data->kind == max6654)
1748 		config |= 0x20;
1749 
1750 	/*
1751 	 * Select external channel 0 for max6695/96
1752 	 */
1753 	if (data->kind == max6696)
1754 		config &= ~0x08;
1755 
1756 	/*
1757 	 * Interrupt is enabled by default on reset, but it may be disabled
1758 	 * by bootloader, unmask it.
1759 	 */
1760 	if (client->irq)
1761 		config &= ~0x80;
1762 
1763 	config &= 0xBF;	/* run */
1764 	lm90_update_confreg(data, config);
1765 
1766 	return devm_add_action_or_reset(&client->dev, lm90_restore_conf, data);
1767 }
1768 
1769 static bool lm90_is_tripped(struct i2c_client *client, u16 *status)
1770 {
1771 	struct lm90_data *data = i2c_get_clientdata(client);
1772 	int st, st2 = 0;
1773 
1774 	st = lm90_read_reg(client, LM90_REG_R_STATUS);
1775 	if (st < 0)
1776 		return false;
1777 
1778 	if (data->kind == max6696) {
1779 		st2 = lm90_read_reg(client, MAX6696_REG_R_STATUS2);
1780 		if (st2 < 0)
1781 			return false;
1782 	}
1783 
1784 	*status = st | (st2 << 8);
1785 
1786 	if ((st & 0x7f) == 0 && (st2 & 0xfe) == 0)
1787 		return false;
1788 
1789 	if ((st & (LM90_STATUS_LLOW | LM90_STATUS_LHIGH | LM90_STATUS_LTHRM)) ||
1790 	    (st2 & MAX6696_STATUS2_LOT2))
1791 		dev_dbg(&client->dev,
1792 			"temp%d out of range, please check!\n", 1);
1793 	if ((st & (LM90_STATUS_RLOW | LM90_STATUS_RHIGH | LM90_STATUS_RTHRM)) ||
1794 	    (st2 & MAX6696_STATUS2_ROT2))
1795 		dev_dbg(&client->dev,
1796 			"temp%d out of range, please check!\n", 2);
1797 	if (st & LM90_STATUS_ROPEN)
1798 		dev_dbg(&client->dev,
1799 			"temp%d diode open, please check!\n", 2);
1800 	if (st2 & (MAX6696_STATUS2_R2LOW | MAX6696_STATUS2_R2HIGH |
1801 		   MAX6696_STATUS2_R2THRM | MAX6696_STATUS2_R2OT2))
1802 		dev_dbg(&client->dev,
1803 			"temp%d out of range, please check!\n", 3);
1804 	if (st2 & MAX6696_STATUS2_R2OPEN)
1805 		dev_dbg(&client->dev,
1806 			"temp%d diode open, please check!\n", 3);
1807 
1808 	if (st & LM90_STATUS_LLOW)
1809 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1810 				   hwmon_temp_min, 0);
1811 	if (st & LM90_STATUS_RLOW)
1812 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1813 				   hwmon_temp_min, 1);
1814 	if (st2 & MAX6696_STATUS2_R2LOW)
1815 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1816 				   hwmon_temp_min, 2);
1817 	if (st & LM90_STATUS_LHIGH)
1818 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1819 				   hwmon_temp_max, 0);
1820 	if (st & LM90_STATUS_RHIGH)
1821 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1822 				   hwmon_temp_max, 1);
1823 	if (st2 & MAX6696_STATUS2_R2HIGH)
1824 		hwmon_notify_event(data->hwmon_dev, hwmon_temp,
1825 				   hwmon_temp_max, 2);
1826 
1827 	return true;
1828 }
1829 
1830 static irqreturn_t lm90_irq_thread(int irq, void *dev_id)
1831 {
1832 	struct i2c_client *client = dev_id;
1833 	u16 status;
1834 
1835 	if (lm90_is_tripped(client, &status))
1836 		return IRQ_HANDLED;
1837 	else
1838 		return IRQ_NONE;
1839 }
1840 
1841 static void lm90_remove_pec(void *dev)
1842 {
1843 	device_remove_file(dev, &dev_attr_pec);
1844 }
1845 
1846 static void lm90_regulator_disable(void *regulator)
1847 {
1848 	regulator_disable(regulator);
1849 }
1850 
1851 
1852 static const struct hwmon_ops lm90_ops = {
1853 	.is_visible = lm90_is_visible,
1854 	.read = lm90_read,
1855 	.write = lm90_write,
1856 };
1857 
1858 static int lm90_probe(struct i2c_client *client)
1859 {
1860 	struct device *dev = &client->dev;
1861 	struct i2c_adapter *adapter = client->adapter;
1862 	struct hwmon_channel_info *info;
1863 	struct regulator *regulator;
1864 	struct device *hwmon_dev;
1865 	struct lm90_data *data;
1866 	int err;
1867 
1868 	regulator = devm_regulator_get(dev, "vcc");
1869 	if (IS_ERR(regulator))
1870 		return PTR_ERR(regulator);
1871 
1872 	err = regulator_enable(regulator);
1873 	if (err < 0) {
1874 		dev_err(dev, "Failed to enable regulator: %d\n", err);
1875 		return err;
1876 	}
1877 
1878 	err = devm_add_action_or_reset(dev, lm90_regulator_disable, regulator);
1879 	if (err)
1880 		return err;
1881 
1882 	data = devm_kzalloc(dev, sizeof(struct lm90_data), GFP_KERNEL);
1883 	if (!data)
1884 		return -ENOMEM;
1885 
1886 	data->client = client;
1887 	i2c_set_clientdata(client, data);
1888 	mutex_init(&data->update_lock);
1889 
1890 	/* Set the device type */
1891 	if (client->dev.of_node)
1892 		data->kind = (enum chips)of_device_get_match_data(&client->dev);
1893 	else
1894 		data->kind = i2c_match_id(lm90_id, client)->driver_data;
1895 	if (data->kind == adm1032) {
1896 		if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
1897 			client->flags &= ~I2C_CLIENT_PEC;
1898 	}
1899 
1900 	/*
1901 	 * Different devices have different alarm bits triggering the
1902 	 * ALERT# output
1903 	 */
1904 	data->alert_alarms = lm90_params[data->kind].alert_alarms;
1905 
1906 	/* Set chip capabilities */
1907 	data->flags = lm90_params[data->kind].flags;
1908 
1909 	data->chip.ops = &lm90_ops;
1910 	data->chip.info = data->info;
1911 
1912 	data->info[0] = HWMON_CHANNEL_INFO(chip,
1913 		HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL | HWMON_C_ALARMS);
1914 	data->info[1] = &data->temp_info;
1915 
1916 	info = &data->temp_info;
1917 	info->type = hwmon_temp;
1918 	info->config = data->channel_config;
1919 
1920 	data->channel_config[0] = HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
1921 		HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM;
1922 	data->channel_config[1] = HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
1923 		HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM | HWMON_T_FAULT;
1924 
1925 	if (data->flags & LM90_HAVE_CRIT) {
1926 		data->channel_config[0] |= HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_CRIT_HYST;
1927 		data->channel_config[1] |= HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_CRIT_HYST;
1928 	}
1929 
1930 	if (data->flags & LM90_HAVE_OFFSET)
1931 		data->channel_config[1] |= HWMON_T_OFFSET;
1932 
1933 	if (data->flags & LM90_HAVE_EMERGENCY) {
1934 		data->channel_config[0] |= HWMON_T_EMERGENCY |
1935 			HWMON_T_EMERGENCY_HYST;
1936 		data->channel_config[1] |= HWMON_T_EMERGENCY |
1937 			HWMON_T_EMERGENCY_HYST;
1938 	}
1939 
1940 	if (data->flags & LM90_HAVE_EMERGENCY_ALARM) {
1941 		data->channel_config[0] |= HWMON_T_EMERGENCY_ALARM;
1942 		data->channel_config[1] |= HWMON_T_EMERGENCY_ALARM;
1943 	}
1944 
1945 	if (data->flags & LM90_HAVE_TEMP3) {
1946 		data->channel_config[2] = HWMON_T_INPUT |
1947 			HWMON_T_MIN | HWMON_T_MAX |
1948 			HWMON_T_CRIT | HWMON_T_CRIT_HYST |
1949 			HWMON_T_EMERGENCY | HWMON_T_EMERGENCY_HYST |
1950 			HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM |
1951 			HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY_ALARM |
1952 			HWMON_T_FAULT;
1953 	}
1954 
1955 	data->reg_local_ext = lm90_params[data->kind].reg_local_ext;
1956 
1957 	/* Set maximum conversion rate */
1958 	data->max_convrate = lm90_params[data->kind].max_convrate;
1959 
1960 	/* Initialize the LM90 chip */
1961 	err = lm90_init_client(client, data);
1962 	if (err < 0) {
1963 		dev_err(dev, "Failed to initialize device\n");
1964 		return err;
1965 	}
1966 
1967 	/*
1968 	 * The 'pec' attribute is attached to the i2c device and thus created
1969 	 * separately.
1970 	 */
1971 	if (client->flags & I2C_CLIENT_PEC) {
1972 		err = device_create_file(dev, &dev_attr_pec);
1973 		if (err)
1974 			return err;
1975 		err = devm_add_action_or_reset(dev, lm90_remove_pec, dev);
1976 		if (err)
1977 			return err;
1978 	}
1979 
1980 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
1981 							 data, &data->chip,
1982 							 NULL);
1983 	if (IS_ERR(hwmon_dev))
1984 		return PTR_ERR(hwmon_dev);
1985 
1986 	data->hwmon_dev = hwmon_dev;
1987 
1988 	if (client->irq) {
1989 		dev_dbg(dev, "IRQ: %d\n", client->irq);
1990 		err = devm_request_threaded_irq(dev, client->irq,
1991 						NULL, lm90_irq_thread,
1992 						IRQF_ONESHOT, "lm90", client);
1993 		if (err < 0) {
1994 			dev_err(dev, "cannot request IRQ %d\n", client->irq);
1995 			return err;
1996 		}
1997 	}
1998 
1999 	return 0;
2000 }
2001 
2002 static void lm90_alert(struct i2c_client *client, enum i2c_alert_protocol type,
2003 		       unsigned int flag)
2004 {
2005 	u16 alarms;
2006 
2007 	if (type != I2C_PROTOCOL_SMBUS_ALERT)
2008 		return;
2009 
2010 	if (lm90_is_tripped(client, &alarms)) {
2011 		/*
2012 		 * Disable ALERT# output, because these chips don't implement
2013 		 * SMBus alert correctly; they should only hold the alert line
2014 		 * low briefly.
2015 		 */
2016 		struct lm90_data *data = i2c_get_clientdata(client);
2017 
2018 		if ((data->flags & LM90_HAVE_BROKEN_ALERT) &&
2019 		    (alarms & data->alert_alarms)) {
2020 			dev_dbg(&client->dev, "Disabling ALERT#\n");
2021 			lm90_update_confreg(data, data->config | 0x80);
2022 		}
2023 	} else {
2024 		dev_dbg(&client->dev, "Everything OK\n");
2025 	}
2026 }
2027 
2028 static int __maybe_unused lm90_suspend(struct device *dev)
2029 {
2030 	struct lm90_data *data = dev_get_drvdata(dev);
2031 	struct i2c_client *client = data->client;
2032 
2033 	if (client->irq)
2034 		disable_irq(client->irq);
2035 
2036 	return 0;
2037 }
2038 
2039 static int __maybe_unused lm90_resume(struct device *dev)
2040 {
2041 	struct lm90_data *data = dev_get_drvdata(dev);
2042 	struct i2c_client *client = data->client;
2043 
2044 	if (client->irq)
2045 		enable_irq(client->irq);
2046 
2047 	return 0;
2048 }
2049 
2050 static SIMPLE_DEV_PM_OPS(lm90_pm_ops, lm90_suspend, lm90_resume);
2051 
2052 static struct i2c_driver lm90_driver = {
2053 	.class		= I2C_CLASS_HWMON,
2054 	.driver = {
2055 		.name	= "lm90",
2056 		.of_match_table = of_match_ptr(lm90_of_match),
2057 		.pm	= &lm90_pm_ops,
2058 	},
2059 	.probe_new	= lm90_probe,
2060 	.alert		= lm90_alert,
2061 	.id_table	= lm90_id,
2062 	.detect		= lm90_detect,
2063 	.address_list	= normal_i2c,
2064 };
2065 
2066 module_i2c_driver(lm90_driver);
2067 
2068 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
2069 MODULE_DESCRIPTION("LM90/ADM1032 driver");
2070 MODULE_LICENSE("GPL");
2071