1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * jc42.c - driver for Jedec JC42.4 compliant temperature sensors
5 * Copyright (c) 2010 Ericsson AB.
7 * Derived from lm77.c by Andras BALI <drewie@freemail.hu>.
9 * JC42.4 compliant temperature sensors are typically used on memory modules.
12 #include <linux/bitops.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/slab.h>
16 #include <linux/jiffies.h>
17 #include <linux/i2c.h>
18 #include <linux/hwmon.h>
19 #include <linux/err.h>
20 #include <linux/mutex.h>
23 /* Addresses to scan */
24 static const unsigned short normal_i2c
[] = {
25 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END
};
27 /* JC42 registers. All registers are 16 bit. */
28 #define JC42_REG_CAP 0x00
29 #define JC42_REG_CONFIG 0x01
30 #define JC42_REG_TEMP_UPPER 0x02
31 #define JC42_REG_TEMP_LOWER 0x03
32 #define JC42_REG_TEMP_CRITICAL 0x04
33 #define JC42_REG_TEMP 0x05
34 #define JC42_REG_MANID 0x06
35 #define JC42_REG_DEVICEID 0x07
36 #define JC42_REG_SMBUS 0x22 /* NXP and Atmel, possibly others? */
38 /* Status bits in temperature register */
39 #define JC42_ALARM_CRIT_BIT 15
40 #define JC42_ALARM_MAX_BIT 14
41 #define JC42_ALARM_MIN_BIT 13
43 /* Configuration register defines */
44 #define JC42_CFG_CRIT_ONLY (1 << 2)
45 #define JC42_CFG_TCRIT_LOCK (1 << 6)
46 #define JC42_CFG_EVENT_LOCK (1 << 7)
47 #define JC42_CFG_SHUTDOWN (1 << 8)
48 #define JC42_CFG_HYST_SHIFT 9
49 #define JC42_CFG_HYST_MASK (0x03 << 9)
52 #define JC42_CAP_RANGE (1 << 2)
54 /* Manufacturer IDs */
55 #define ADT_MANID 0x11d4 /* Analog Devices */
56 #define ATMEL_MANID 0x001f /* Atmel */
57 #define ATMEL_MANID2 0x1114 /* Atmel */
58 #define MAX_MANID 0x004d /* Maxim */
59 #define IDT_MANID 0x00b3 /* IDT */
60 #define MCP_MANID 0x0054 /* Microchip */
61 #define NXP_MANID 0x1131 /* NXP Semiconductors */
62 #define ONS_MANID 0x1b09 /* ON Semiconductor */
63 #define STM_MANID 0x104a /* ST Microelectronics */
64 #define GT_MANID 0x1c68 /* Giantec */
65 #define GT_MANID2 0x132d /* Giantec, 2nd mfg ID */
68 #define SMBUS_STMOUT BIT(7) /* SMBus time-out, active low */
73 #define ADT7408_DEVID 0x0801
74 #define ADT7408_DEVID_MASK 0xffff
77 #define AT30TS00_DEVID 0x8201
78 #define AT30TS00_DEVID_MASK 0xffff
80 #define AT30TSE004_DEVID 0x2200
81 #define AT30TSE004_DEVID_MASK 0xffff
84 #define GT30TS00_DEVID 0x2200
85 #define GT30TS00_DEVID_MASK 0xff00
87 #define GT34TS02_DEVID 0x3300
88 #define GT34TS02_DEVID_MASK 0xff00
91 #define TSE2004_DEVID 0x2200
92 #define TSE2004_DEVID_MASK 0xff00
94 #define TS3000_DEVID 0x2900 /* Also matches TSE2002 */
95 #define TS3000_DEVID_MASK 0xff00
97 #define TS3001_DEVID 0x3000
98 #define TS3001_DEVID_MASK 0xff00
101 #define MAX6604_DEVID 0x3e00
102 #define MAX6604_DEVID_MASK 0xffff
105 #define MCP9804_DEVID 0x0200
106 #define MCP9804_DEVID_MASK 0xfffc
108 #define MCP9808_DEVID 0x0400
109 #define MCP9808_DEVID_MASK 0xfffc
111 #define MCP98242_DEVID 0x2000
112 #define MCP98242_DEVID_MASK 0xfffc
114 #define MCP98243_DEVID 0x2100
115 #define MCP98243_DEVID_MASK 0xfffc
117 #define MCP98244_DEVID 0x2200
118 #define MCP98244_DEVID_MASK 0xfffc
120 #define MCP9843_DEVID 0x0000 /* Also matches mcp9805 */
121 #define MCP9843_DEVID_MASK 0xfffe
124 #define SE97_DEVID 0xa200
125 #define SE97_DEVID_MASK 0xfffc
127 #define SE98_DEVID 0xa100
128 #define SE98_DEVID_MASK 0xfffc
130 /* ON Semiconductor */
131 #define CAT6095_DEVID 0x0800 /* Also matches CAT34TS02 */
132 #define CAT6095_DEVID_MASK 0xffe0
134 #define CAT34TS02C_DEVID 0x0a00
135 #define CAT34TS02C_DEVID_MASK 0xfff0
137 #define CAT34TS04_DEVID 0x2200
138 #define CAT34TS04_DEVID_MASK 0xfff0
140 /* ST Microelectronics */
141 #define STTS424_DEVID 0x0101
142 #define STTS424_DEVID_MASK 0xffff
144 #define STTS424E_DEVID 0x0000
145 #define STTS424E_DEVID_MASK 0xfffe
147 #define STTS2002_DEVID 0x0300
148 #define STTS2002_DEVID_MASK 0xffff
150 #define STTS2004_DEVID 0x2201
151 #define STTS2004_DEVID_MASK 0xffff
153 #define STTS3000_DEVID 0x0200
154 #define STTS3000_DEVID_MASK 0xffff
156 static u16 jc42_hysteresis
[] = { 0, 1500, 3000, 6000 };
164 static struct jc42_chips jc42_chips
[] = {
165 { ADT_MANID
, ADT7408_DEVID
, ADT7408_DEVID_MASK
},
166 { ATMEL_MANID
, AT30TS00_DEVID
, AT30TS00_DEVID_MASK
},
167 { ATMEL_MANID2
, AT30TSE004_DEVID
, AT30TSE004_DEVID_MASK
},
168 { GT_MANID
, GT30TS00_DEVID
, GT30TS00_DEVID_MASK
},
169 { GT_MANID2
, GT34TS02_DEVID
, GT34TS02_DEVID_MASK
},
170 { IDT_MANID
, TSE2004_DEVID
, TSE2004_DEVID_MASK
},
171 { IDT_MANID
, TS3000_DEVID
, TS3000_DEVID_MASK
},
172 { IDT_MANID
, TS3001_DEVID
, TS3001_DEVID_MASK
},
173 { MAX_MANID
, MAX6604_DEVID
, MAX6604_DEVID_MASK
},
174 { MCP_MANID
, MCP9804_DEVID
, MCP9804_DEVID_MASK
},
175 { MCP_MANID
, MCP9808_DEVID
, MCP9808_DEVID_MASK
},
176 { MCP_MANID
, MCP98242_DEVID
, MCP98242_DEVID_MASK
},
177 { MCP_MANID
, MCP98243_DEVID
, MCP98243_DEVID_MASK
},
178 { MCP_MANID
, MCP98244_DEVID
, MCP98244_DEVID_MASK
},
179 { MCP_MANID
, MCP9843_DEVID
, MCP9843_DEVID_MASK
},
180 { NXP_MANID
, SE97_DEVID
, SE97_DEVID_MASK
},
181 { ONS_MANID
, CAT6095_DEVID
, CAT6095_DEVID_MASK
},
182 { ONS_MANID
, CAT34TS02C_DEVID
, CAT34TS02C_DEVID_MASK
},
183 { ONS_MANID
, CAT34TS04_DEVID
, CAT34TS04_DEVID_MASK
},
184 { NXP_MANID
, SE98_DEVID
, SE98_DEVID_MASK
},
185 { STM_MANID
, STTS424_DEVID
, STTS424_DEVID_MASK
},
186 { STM_MANID
, STTS424E_DEVID
, STTS424E_DEVID_MASK
},
187 { STM_MANID
, STTS2002_DEVID
, STTS2002_DEVID_MASK
},
188 { STM_MANID
, STTS2004_DEVID
, STTS2004_DEVID_MASK
},
189 { STM_MANID
, STTS3000_DEVID
, STTS3000_DEVID_MASK
},
200 static const u8 temp_regs
[t_num_temp
] = {
201 [t_input
] = JC42_REG_TEMP
,
202 [t_crit
] = JC42_REG_TEMP_CRITICAL
,
203 [t_min
] = JC42_REG_TEMP_LOWER
,
204 [t_max
] = JC42_REG_TEMP_UPPER
,
207 /* Each client has this additional data */
209 struct i2c_client
*client
;
210 struct mutex update_lock
; /* protect register access */
211 bool extended
; /* true if extended range supported */
213 unsigned long last_updated
; /* In jiffies */
214 u16 orig_config
; /* original configuration */
215 u16 config
; /* current configuration */
216 u16 temp
[t_num_temp
];/* Temperatures */
219 #define JC42_TEMP_MIN_EXTENDED (-40000)
220 #define JC42_TEMP_MIN 0
221 #define JC42_TEMP_MAX 125000
223 static u16
jc42_temp_to_reg(long temp
, bool extended
)
225 int ntemp
= clamp_val(temp
,
226 extended
? JC42_TEMP_MIN_EXTENDED
:
227 JC42_TEMP_MIN
, JC42_TEMP_MAX
);
229 /* convert from 0.001 to 0.0625 resolution */
230 return (ntemp
* 2 / 125) & 0x1fff;
233 static int jc42_temp_from_reg(s16 reg
)
235 reg
= sign_extend32(reg
, 12);
237 /* convert from 0.0625 to 0.001 resolution */
238 return reg
* 125 / 2;
241 static struct jc42_data
*jc42_update_device(struct device
*dev
)
243 struct jc42_data
*data
= dev_get_drvdata(dev
);
244 struct i2c_client
*client
= data
->client
;
245 struct jc42_data
*ret
= data
;
248 mutex_lock(&data
->update_lock
);
250 if (time_after(jiffies
, data
->last_updated
+ HZ
) || !data
->valid
) {
251 for (i
= 0; i
< t_num_temp
; i
++) {
252 val
= i2c_smbus_read_word_swapped(client
, temp_regs
[i
]);
259 data
->last_updated
= jiffies
;
263 mutex_unlock(&data
->update_lock
);
267 static int jc42_read(struct device
*dev
, enum hwmon_sensor_types type
,
268 u32 attr
, int channel
, long *val
)
270 struct jc42_data
*data
= jc42_update_device(dev
);
274 return PTR_ERR(data
);
277 case hwmon_temp_input
:
278 *val
= jc42_temp_from_reg(data
->temp
[t_input
]);
281 *val
= jc42_temp_from_reg(data
->temp
[t_min
]);
284 *val
= jc42_temp_from_reg(data
->temp
[t_max
]);
286 case hwmon_temp_crit
:
287 *val
= jc42_temp_from_reg(data
->temp
[t_crit
]);
289 case hwmon_temp_max_hyst
:
290 temp
= jc42_temp_from_reg(data
->temp
[t_max
]);
291 hyst
= jc42_hysteresis
[(data
->config
& JC42_CFG_HYST_MASK
)
292 >> JC42_CFG_HYST_SHIFT
];
295 case hwmon_temp_crit_hyst
:
296 temp
= jc42_temp_from_reg(data
->temp
[t_crit
]);
297 hyst
= jc42_hysteresis
[(data
->config
& JC42_CFG_HYST_MASK
)
298 >> JC42_CFG_HYST_SHIFT
];
301 case hwmon_temp_min_alarm
:
302 *val
= (data
->temp
[t_input
] >> JC42_ALARM_MIN_BIT
) & 1;
304 case hwmon_temp_max_alarm
:
305 *val
= (data
->temp
[t_input
] >> JC42_ALARM_MAX_BIT
) & 1;
307 case hwmon_temp_crit_alarm
:
308 *val
= (data
->temp
[t_input
] >> JC42_ALARM_CRIT_BIT
) & 1;
315 static int jc42_write(struct device
*dev
, enum hwmon_sensor_types type
,
316 u32 attr
, int channel
, long val
)
318 struct jc42_data
*data
= dev_get_drvdata(dev
);
319 struct i2c_client
*client
= data
->client
;
323 mutex_lock(&data
->update_lock
);
327 data
->temp
[t_min
] = jc42_temp_to_reg(val
, data
->extended
);
328 ret
= i2c_smbus_write_word_swapped(client
, temp_regs
[t_min
],
332 data
->temp
[t_max
] = jc42_temp_to_reg(val
, data
->extended
);
333 ret
= i2c_smbus_write_word_swapped(client
, temp_regs
[t_max
],
336 case hwmon_temp_crit
:
337 data
->temp
[t_crit
] = jc42_temp_to_reg(val
, data
->extended
);
338 ret
= i2c_smbus_write_word_swapped(client
, temp_regs
[t_crit
],
341 case hwmon_temp_crit_hyst
:
343 * JC42.4 compliant chips only support four hysteresis values.
344 * Pick best choice and go from there.
346 val
= clamp_val(val
, (data
->extended
? JC42_TEMP_MIN_EXTENDED
347 : JC42_TEMP_MIN
) - 6000,
349 diff
= jc42_temp_from_reg(data
->temp
[t_crit
]) - val
;
353 hyst
= 1; /* 1.5 degrees C */
354 else if (diff
< 4500)
355 hyst
= 2; /* 3.0 degrees C */
357 hyst
= 3; /* 6.0 degrees C */
359 data
->config
= (data
->config
& ~JC42_CFG_HYST_MASK
) |
360 (hyst
<< JC42_CFG_HYST_SHIFT
);
361 ret
= i2c_smbus_write_word_swapped(data
->client
,
370 mutex_unlock(&data
->update_lock
);
375 static umode_t
jc42_is_visible(const void *_data
, enum hwmon_sensor_types type
,
376 u32 attr
, int channel
)
378 const struct jc42_data
*data
= _data
;
379 unsigned int config
= data
->config
;
385 if (!(config
& JC42_CFG_EVENT_LOCK
))
388 case hwmon_temp_crit
:
389 if (!(config
& JC42_CFG_TCRIT_LOCK
))
392 case hwmon_temp_crit_hyst
:
393 if (!(config
& (JC42_CFG_EVENT_LOCK
| JC42_CFG_TCRIT_LOCK
)))
396 case hwmon_temp_input
:
397 case hwmon_temp_max_hyst
:
398 case hwmon_temp_min_alarm
:
399 case hwmon_temp_max_alarm
:
400 case hwmon_temp_crit_alarm
:
409 /* Return 0 if detection is successful, -ENODEV otherwise */
410 static int jc42_detect(struct i2c_client
*client
, struct i2c_board_info
*info
)
412 struct i2c_adapter
*adapter
= client
->adapter
;
413 int i
, config
, cap
, manid
, devid
;
415 if (!i2c_check_functionality(adapter
, I2C_FUNC_SMBUS_BYTE_DATA
|
416 I2C_FUNC_SMBUS_WORD_DATA
))
419 cap
= i2c_smbus_read_word_swapped(client
, JC42_REG_CAP
);
420 config
= i2c_smbus_read_word_swapped(client
, JC42_REG_CONFIG
);
421 manid
= i2c_smbus_read_word_swapped(client
, JC42_REG_MANID
);
422 devid
= i2c_smbus_read_word_swapped(client
, JC42_REG_DEVICEID
);
424 if (cap
< 0 || config
< 0 || manid
< 0 || devid
< 0)
427 if ((cap
& 0xff00) || (config
& 0xf800))
430 for (i
= 0; i
< ARRAY_SIZE(jc42_chips
); i
++) {
431 struct jc42_chips
*chip
= &jc42_chips
[i
];
432 if (manid
== chip
->manid
&&
433 (devid
& chip
->devid_mask
) == chip
->devid
) {
434 strlcpy(info
->type
, "jc42", I2C_NAME_SIZE
);
441 static const struct hwmon_channel_info
*jc42_info
[] = {
442 HWMON_CHANNEL_INFO(temp
,
443 HWMON_T_INPUT
| HWMON_T_MIN
| HWMON_T_MAX
|
444 HWMON_T_CRIT
| HWMON_T_MAX_HYST
|
445 HWMON_T_CRIT_HYST
| HWMON_T_MIN_ALARM
|
446 HWMON_T_MAX_ALARM
| HWMON_T_CRIT_ALARM
),
450 static const struct hwmon_ops jc42_hwmon_ops
= {
451 .is_visible
= jc42_is_visible
,
456 static const struct hwmon_chip_info jc42_chip_info
= {
457 .ops
= &jc42_hwmon_ops
,
461 static int jc42_probe(struct i2c_client
*client
, const struct i2c_device_id
*id
)
463 struct device
*dev
= &client
->dev
;
464 struct device
*hwmon_dev
;
465 struct jc42_data
*data
;
468 data
= devm_kzalloc(dev
, sizeof(struct jc42_data
), GFP_KERNEL
);
472 data
->client
= client
;
473 i2c_set_clientdata(client
, data
);
474 mutex_init(&data
->update_lock
);
476 cap
= i2c_smbus_read_word_swapped(client
, JC42_REG_CAP
);
480 data
->extended
= !!(cap
& JC42_CAP_RANGE
);
482 if (device_property_read_bool(dev
, "smbus-timeout-disable")) {
486 * Not all chips support this register, but from a
487 * quick read of various datasheets no chip appears
488 * incompatible with the below attempt to disable
489 * the timeout. And the whole thing is opt-in...
491 smbus
= i2c_smbus_read_word_swapped(client
, JC42_REG_SMBUS
);
494 i2c_smbus_write_word_swapped(client
, JC42_REG_SMBUS
,
495 smbus
| SMBUS_STMOUT
);
498 config
= i2c_smbus_read_word_swapped(client
, JC42_REG_CONFIG
);
502 data
->orig_config
= config
;
503 if (config
& JC42_CFG_SHUTDOWN
) {
504 config
&= ~JC42_CFG_SHUTDOWN
;
505 i2c_smbus_write_word_swapped(client
, JC42_REG_CONFIG
, config
);
507 data
->config
= config
;
509 hwmon_dev
= devm_hwmon_device_register_with_info(dev
, "jc42",
510 data
, &jc42_chip_info
,
512 return PTR_ERR_OR_ZERO(hwmon_dev
);
515 static int jc42_remove(struct i2c_client
*client
)
517 struct jc42_data
*data
= i2c_get_clientdata(client
);
519 /* Restore original configuration except hysteresis */
520 if ((data
->config
& ~JC42_CFG_HYST_MASK
) !=
521 (data
->orig_config
& ~JC42_CFG_HYST_MASK
)) {
524 config
= (data
->orig_config
& ~JC42_CFG_HYST_MASK
)
525 | (data
->config
& JC42_CFG_HYST_MASK
);
526 i2c_smbus_write_word_swapped(client
, JC42_REG_CONFIG
, config
);
533 static int jc42_suspend(struct device
*dev
)
535 struct jc42_data
*data
= dev_get_drvdata(dev
);
537 data
->config
|= JC42_CFG_SHUTDOWN
;
538 i2c_smbus_write_word_swapped(data
->client
, JC42_REG_CONFIG
,
543 static int jc42_resume(struct device
*dev
)
545 struct jc42_data
*data
= dev_get_drvdata(dev
);
547 data
->config
&= ~JC42_CFG_SHUTDOWN
;
548 i2c_smbus_write_word_swapped(data
->client
, JC42_REG_CONFIG
,
553 static const struct dev_pm_ops jc42_dev_pm_ops
= {
554 .suspend
= jc42_suspend
,
555 .resume
= jc42_resume
,
558 #define JC42_DEV_PM_OPS (&jc42_dev_pm_ops)
560 #define JC42_DEV_PM_OPS NULL
561 #endif /* CONFIG_PM */
563 static const struct i2c_device_id jc42_id
[] = {
567 MODULE_DEVICE_TABLE(i2c
, jc42_id
);
570 static const struct of_device_id jc42_of_ids
[] = {
571 { .compatible
= "jedec,jc-42.4-temp", },
574 MODULE_DEVICE_TABLE(of
, jc42_of_ids
);
577 static struct i2c_driver jc42_driver
= {
578 .class = I2C_CLASS_SPD
| I2C_CLASS_HWMON
,
581 .pm
= JC42_DEV_PM_OPS
,
582 .of_match_table
= of_match_ptr(jc42_of_ids
),
585 .remove
= jc42_remove
,
587 .detect
= jc42_detect
,
588 .address_list
= normal_i2c
,
591 module_i2c_driver(jc42_driver
);
593 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
594 MODULE_DESCRIPTION("JC42 driver");
595 MODULE_LICENSE("GPL");