1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * adt7x10.c - Part of lm_sensors, Linux kernel modules for hardware
4  *	 monitoring
5  * This driver handles the ADT7410 and compatible digital temperature sensors.
6  * Hartmut Knaack <knaack.h@gmx.de> 2012-07-22
7  * based on lm75.c by Frodo Looijaard <frodol@dds.nl>
8  * and adt7410.c from iio-staging by Sonic Zhang <sonic.zhang@analog.com>
9  */
10 
11 #include <linux/device.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/slab.h>
15 #include <linux/jiffies.h>
16 #include <linux/hwmon.h>
17 #include <linux/err.h>
18 #include <linux/mutex.h>
19 #include <linux/delay.h>
20 #include <linux/interrupt.h>
21 #include <linux/regmap.h>
22 
23 #include "adt7x10.h"
24 
25 /*
26  * ADT7X10 status
27  */
28 #define ADT7X10_STAT_T_LOW		(1 << 4)
29 #define ADT7X10_STAT_T_HIGH		(1 << 5)
30 #define ADT7X10_STAT_T_CRIT		(1 << 6)
31 #define ADT7X10_STAT_NOT_RDY		(1 << 7)
32 
33 /*
34  * ADT7X10 config
35  */
36 #define ADT7X10_FAULT_QUEUE_MASK	(1 << 0 | 1 << 1)
37 #define ADT7X10_CT_POLARITY		(1 << 2)
38 #define ADT7X10_INT_POLARITY		(1 << 3)
39 #define ADT7X10_EVENT_MODE		(1 << 4)
40 #define ADT7X10_MODE_MASK		(1 << 5 | 1 << 6)
41 #define ADT7X10_FULL			(0 << 5 | 0 << 6)
42 #define ADT7X10_PD			(1 << 5 | 1 << 6)
43 #define ADT7X10_RESOLUTION		(1 << 7)
44 
45 /*
46  * ADT7X10 masks
47  */
48 #define ADT7X10_T13_VALUE_MASK		0xFFF8
49 #define ADT7X10_T_HYST_MASK		0xF
50 
51 /* straight from the datasheet */
52 #define ADT7X10_TEMP_MIN (-55000)
53 #define ADT7X10_TEMP_MAX 150000
54 
55 /* Each client has this additional data */
56 struct adt7x10_data {
57 	struct regmap		*regmap;
58 	struct mutex		update_lock;
59 	u8			config;
60 	u8			oldconfig;
61 	bool			valid;		/* true if temperature valid */
62 };
63 
64 enum {
65 	adt7x10_temperature = 0,
66 	adt7x10_t_alarm_high,
67 	adt7x10_t_alarm_low,
68 	adt7x10_t_crit,
69 };
70 
71 static const u8 ADT7X10_REG_TEMP[] = {
72 	[adt7x10_temperature] = ADT7X10_TEMPERATURE,		/* input */
73 	[adt7x10_t_alarm_high] = ADT7X10_T_ALARM_HIGH,		/* high */
74 	[adt7x10_t_alarm_low] = ADT7X10_T_ALARM_LOW,		/* low */
75 	[adt7x10_t_crit] = ADT7X10_T_CRIT,			/* critical */
76 };
77 
adt7x10_irq_handler(int irq,void * private)78 static irqreturn_t adt7x10_irq_handler(int irq, void *private)
79 {
80 	struct device *dev = private;
81 	struct adt7x10_data *d = dev_get_drvdata(dev);
82 	unsigned int status;
83 	int ret;
84 
85 	ret = regmap_read(d->regmap, ADT7X10_STATUS, &status);
86 	if (ret < 0)
87 		return IRQ_HANDLED;
88 
89 	if (status & ADT7X10_STAT_T_HIGH)
90 		hwmon_notify_event(dev, hwmon_temp, hwmon_temp_max_alarm, 0);
91 	if (status & ADT7X10_STAT_T_LOW)
92 		hwmon_notify_event(dev, hwmon_temp, hwmon_temp_min_alarm, 0);
93 	if (status & ADT7X10_STAT_T_CRIT)
94 		hwmon_notify_event(dev, hwmon_temp, hwmon_temp_crit_alarm, 0);
95 
96 	return IRQ_HANDLED;
97 }
98 
adt7x10_temp_ready(struct regmap * regmap)99 static int adt7x10_temp_ready(struct regmap *regmap)
100 {
101 	unsigned int status;
102 	int i, ret;
103 
104 	for (i = 0; i < 6; i++) {
105 		ret = regmap_read(regmap, ADT7X10_STATUS, &status);
106 		if (ret < 0)
107 			return ret;
108 		if (!(status & ADT7X10_STAT_NOT_RDY))
109 			return 0;
110 		msleep(60);
111 	}
112 	return -ETIMEDOUT;
113 }
114 
ADT7X10_TEMP_TO_REG(long temp)115 static s16 ADT7X10_TEMP_TO_REG(long temp)
116 {
117 	return DIV_ROUND_CLOSEST(clamp_val(temp, ADT7X10_TEMP_MIN,
118 					   ADT7X10_TEMP_MAX) * 128, 1000);
119 }
120 
ADT7X10_REG_TO_TEMP(struct adt7x10_data * data,s16 reg)121 static int ADT7X10_REG_TO_TEMP(struct adt7x10_data *data, s16 reg)
122 {
123 	/* in 13 bit mode, bits 0-2 are status flags - mask them out */
124 	if (!(data->config & ADT7X10_RESOLUTION))
125 		reg &= ADT7X10_T13_VALUE_MASK;
126 	/*
127 	 * temperature is stored in twos complement format, in steps of
128 	 * 1/128°C
129 	 */
130 	return DIV_ROUND_CLOSEST(reg * 1000, 128);
131 }
132 
133 /*-----------------------------------------------------------------------*/
134 
adt7x10_temp_read(struct adt7x10_data * data,int index,long * val)135 static int adt7x10_temp_read(struct adt7x10_data *data, int index, long *val)
136 {
137 	unsigned int regval;
138 	int ret;
139 
140 	mutex_lock(&data->update_lock);
141 	if (index == adt7x10_temperature && !data->valid) {
142 		/* wait for valid temperature */
143 		ret = adt7x10_temp_ready(data->regmap);
144 		if (ret) {
145 			mutex_unlock(&data->update_lock);
146 			return ret;
147 		}
148 		data->valid = true;
149 	}
150 	mutex_unlock(&data->update_lock);
151 
152 	ret = regmap_read(data->regmap, ADT7X10_REG_TEMP[index], &regval);
153 	if (ret)
154 		return ret;
155 
156 	*val = ADT7X10_REG_TO_TEMP(data, regval);
157 	return 0;
158 }
159 
adt7x10_temp_write(struct adt7x10_data * data,int index,long temp)160 static int adt7x10_temp_write(struct adt7x10_data *data, int index, long temp)
161 {
162 	int ret;
163 
164 	mutex_lock(&data->update_lock);
165 	ret = regmap_write(data->regmap, ADT7X10_REG_TEMP[index],
166 			   ADT7X10_TEMP_TO_REG(temp));
167 	mutex_unlock(&data->update_lock);
168 	return ret;
169 }
170 
adt7x10_hyst_read(struct adt7x10_data * data,int index,long * val)171 static int adt7x10_hyst_read(struct adt7x10_data *data, int index, long *val)
172 {
173 	int hyst, temp, ret;
174 
175 	mutex_lock(&data->update_lock);
176 	ret = regmap_read(data->regmap, ADT7X10_T_HYST, &hyst);
177 	if (ret) {
178 		mutex_unlock(&data->update_lock);
179 		return ret;
180 	}
181 
182 	ret = regmap_read(data->regmap, ADT7X10_REG_TEMP[index], &temp);
183 	mutex_unlock(&data->update_lock);
184 	if (ret)
185 		return ret;
186 
187 	hyst = (hyst & ADT7X10_T_HYST_MASK) * 1000;
188 
189 	/*
190 	 * hysteresis is stored as a 4 bit offset in the device, convert it
191 	 * to an absolute value
192 	 */
193 	/* min has positive offset, others have negative */
194 	if (index == adt7x10_t_alarm_low)
195 		hyst = -hyst;
196 
197 	*val = ADT7X10_REG_TO_TEMP(data, temp) - hyst;
198 	return 0;
199 }
200 
adt7x10_hyst_write(struct adt7x10_data * data,long hyst)201 static int adt7x10_hyst_write(struct adt7x10_data *data, long hyst)
202 {
203 	unsigned int regval;
204 	int limit, ret;
205 
206 	mutex_lock(&data->update_lock);
207 
208 	/* convert absolute hysteresis value to a 4 bit delta value */
209 	ret = regmap_read(data->regmap, ADT7X10_T_ALARM_HIGH, &regval);
210 	if (ret < 0)
211 		goto abort;
212 
213 	limit = ADT7X10_REG_TO_TEMP(data, regval);
214 
215 	hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX);
216 	regval = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000), 0,
217 			   ADT7X10_T_HYST_MASK);
218 	ret = regmap_write(data->regmap, ADT7X10_T_HYST, regval);
219 abort:
220 	mutex_unlock(&data->update_lock);
221 	return ret;
222 }
223 
adt7x10_alarm_read(struct adt7x10_data * data,int index,long * val)224 static int adt7x10_alarm_read(struct adt7x10_data *data, int index, long *val)
225 {
226 	unsigned int status;
227 	int ret;
228 
229 	ret = regmap_read(data->regmap, ADT7X10_STATUS, &status);
230 	if (ret < 0)
231 		return ret;
232 
233 	*val = !!(status & index);
234 
235 	return 0;
236 }
237 
adt7x10_is_visible(const void * data,enum hwmon_sensor_types type,u32 attr,int channel)238 static umode_t adt7x10_is_visible(const void *data,
239 				  enum hwmon_sensor_types type,
240 				  u32 attr, int channel)
241 {
242 	switch (attr) {
243 	case hwmon_temp_max:
244 	case hwmon_temp_min:
245 	case hwmon_temp_crit:
246 	case hwmon_temp_max_hyst:
247 		return 0644;
248 	case hwmon_temp_input:
249 	case hwmon_temp_min_alarm:
250 	case hwmon_temp_max_alarm:
251 	case hwmon_temp_crit_alarm:
252 	case hwmon_temp_min_hyst:
253 	case hwmon_temp_crit_hyst:
254 		return 0444;
255 	default:
256 		break;
257 	}
258 
259 	return 0;
260 }
261 
adt7x10_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)262 static int adt7x10_read(struct device *dev, enum hwmon_sensor_types type,
263 			u32 attr, int channel, long *val)
264 {
265 	struct adt7x10_data *data = dev_get_drvdata(dev);
266 
267 	switch (attr) {
268 	case hwmon_temp_input:
269 		return adt7x10_temp_read(data, adt7x10_temperature, val);
270 	case hwmon_temp_max:
271 		return adt7x10_temp_read(data, adt7x10_t_alarm_high, val);
272 	case hwmon_temp_min:
273 		return adt7x10_temp_read(data, adt7x10_t_alarm_low, val);
274 	case hwmon_temp_crit:
275 		return adt7x10_temp_read(data, adt7x10_t_crit, val);
276 	case hwmon_temp_max_hyst:
277 		return adt7x10_hyst_read(data, adt7x10_t_alarm_high, val);
278 	case hwmon_temp_min_hyst:
279 		return adt7x10_hyst_read(data, adt7x10_t_alarm_low, val);
280 	case hwmon_temp_crit_hyst:
281 		return adt7x10_hyst_read(data, adt7x10_t_crit, val);
282 	case hwmon_temp_min_alarm:
283 		return adt7x10_alarm_read(data, ADT7X10_STAT_T_LOW, val);
284 	case hwmon_temp_max_alarm:
285 		return adt7x10_alarm_read(data, ADT7X10_STAT_T_HIGH, val);
286 	case hwmon_temp_crit_alarm:
287 		return adt7x10_alarm_read(data, ADT7X10_STAT_T_CRIT, val);
288 	default:
289 		return -EOPNOTSUPP;
290 	}
291 }
292 
adt7x10_write(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long val)293 static int adt7x10_write(struct device *dev, enum hwmon_sensor_types type,
294 			 u32 attr, int channel, long val)
295 {
296 	struct adt7x10_data *data = dev_get_drvdata(dev);
297 
298 	switch (attr) {
299 	case hwmon_temp_max:
300 		return adt7x10_temp_write(data, adt7x10_t_alarm_high, val);
301 	case hwmon_temp_min:
302 		return adt7x10_temp_write(data, adt7x10_t_alarm_low, val);
303 	case hwmon_temp_crit:
304 		return adt7x10_temp_write(data, adt7x10_t_crit, val);
305 	case hwmon_temp_max_hyst:
306 		return adt7x10_hyst_write(data, val);
307 	default:
308 		return -EOPNOTSUPP;
309 	}
310 }
311 
312 static const struct hwmon_channel_info * const adt7x10_info[] = {
313 	HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN |
314 			   HWMON_T_CRIT | HWMON_T_MAX_HYST | HWMON_T_MIN_HYST |
315 			   HWMON_T_CRIT_HYST | HWMON_T_MIN_ALARM |
316 			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM),
317 	NULL,
318 };
319 
320 static const struct hwmon_ops adt7x10_hwmon_ops = {
321 	.is_visible = adt7x10_is_visible,
322 	.read = adt7x10_read,
323 	.write = adt7x10_write,
324 };
325 
326 static const struct hwmon_chip_info adt7x10_chip_info = {
327 	.ops = &adt7x10_hwmon_ops,
328 	.info = adt7x10_info,
329 };
330 
adt7x10_restore_config(void * private)331 static void adt7x10_restore_config(void *private)
332 {
333 	struct adt7x10_data *data = private;
334 
335 	regmap_write(data->regmap, ADT7X10_CONFIG, data->oldconfig);
336 }
337 
adt7x10_probe(struct device * dev,const char * name,int irq,struct regmap * regmap)338 int adt7x10_probe(struct device *dev, const char *name, int irq,
339 		  struct regmap *regmap)
340 {
341 	struct adt7x10_data *data;
342 	unsigned int config;
343 	struct device *hdev;
344 	int ret;
345 
346 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
347 	if (!data)
348 		return -ENOMEM;
349 
350 	data->regmap = regmap;
351 
352 	dev_set_drvdata(dev, data);
353 	mutex_init(&data->update_lock);
354 
355 	/* configure as specified */
356 	ret = regmap_read(regmap, ADT7X10_CONFIG, &config);
357 	if (ret < 0) {
358 		dev_dbg(dev, "Can't read config? %d\n", ret);
359 		return ret;
360 	}
361 	data->oldconfig = config;
362 
363 	/*
364 	 * Set to 16 bit resolution, continous conversion and comparator mode.
365 	 */
366 	data->config = data->oldconfig;
367 	data->config &= ~(ADT7X10_MODE_MASK | ADT7X10_CT_POLARITY |
368 			ADT7X10_INT_POLARITY);
369 	data->config |= ADT7X10_FULL | ADT7X10_RESOLUTION | ADT7X10_EVENT_MODE;
370 
371 	if (data->config != data->oldconfig) {
372 		ret = regmap_write(regmap, ADT7X10_CONFIG, data->config);
373 		if (ret)
374 			return ret;
375 		ret = devm_add_action_or_reset(dev, adt7x10_restore_config, data);
376 		if (ret)
377 			return ret;
378 	}
379 	dev_dbg(dev, "Config %02x\n", data->config);
380 
381 	hdev = devm_hwmon_device_register_with_info(dev, name, data,
382 						    &adt7x10_chip_info, NULL);
383 	if (IS_ERR(hdev))
384 		return PTR_ERR(hdev);
385 
386 	if (irq > 0) {
387 		ret = devm_request_threaded_irq(dev, irq, NULL,
388 						adt7x10_irq_handler,
389 						IRQF_TRIGGER_FALLING |
390 						IRQF_ONESHOT,
391 						dev_name(dev), hdev);
392 		if (ret)
393 			return ret;
394 	}
395 
396 	return 0;
397 }
398 EXPORT_SYMBOL_GPL(adt7x10_probe);
399 
adt7x10_suspend(struct device * dev)400 static int adt7x10_suspend(struct device *dev)
401 {
402 	struct adt7x10_data *data = dev_get_drvdata(dev);
403 
404 	return regmap_write(data->regmap, ADT7X10_CONFIG,
405 			    data->config | ADT7X10_PD);
406 }
407 
adt7x10_resume(struct device * dev)408 static int adt7x10_resume(struct device *dev)
409 {
410 	struct adt7x10_data *data = dev_get_drvdata(dev);
411 
412 	return regmap_write(data->regmap, ADT7X10_CONFIG, data->config);
413 }
414 
415 EXPORT_SIMPLE_DEV_PM_OPS(adt7x10_dev_pm_ops, adt7x10_suspend, adt7x10_resume);
416 
417 MODULE_AUTHOR("Hartmut Knaack");
418 MODULE_DESCRIPTION("ADT7410/ADT7420, ADT7310/ADT7320 common code");
419 MODULE_LICENSE("GPL");
420