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 	unsigned int regs[2] = {ADT7X10_T_HYST, ADT7X10_REG_TEMP[index]};
174 	int hyst, ret;
175 	u16 regdata[2];
176 
177 	ret = regmap_multi_reg_read(data->regmap, regs, regdata, 2);
178 	if (ret)
179 		return ret;
180 
181 	hyst = (regdata[0] & ADT7X10_T_HYST_MASK) * 1000;
182 
183 	/*
184 	 * hysteresis is stored as a 4 bit offset in the device, convert it
185 	 * to an absolute value
186 	 */
187 	/* min has positive offset, others have negative */
188 	if (index == adt7x10_t_alarm_low)
189 		hyst = -hyst;
190 
191 	*val = ADT7X10_REG_TO_TEMP(data, regdata[1]) - hyst;
192 	return 0;
193 }
194 
adt7x10_hyst_write(struct adt7x10_data * data,long hyst)195 static int adt7x10_hyst_write(struct adt7x10_data *data, long hyst)
196 {
197 	unsigned int regval;
198 	int limit, ret;
199 
200 	mutex_lock(&data->update_lock);
201 
202 	/* convert absolute hysteresis value to a 4 bit delta value */
203 	ret = regmap_read(data->regmap, ADT7X10_T_ALARM_HIGH, &regval);
204 	if (ret < 0)
205 		goto abort;
206 
207 	limit = ADT7X10_REG_TO_TEMP(data, regval);
208 
209 	hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX);
210 	regval = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000), 0,
211 			   ADT7X10_T_HYST_MASK);
212 	ret = regmap_write(data->regmap, ADT7X10_T_HYST, regval);
213 abort:
214 	mutex_unlock(&data->update_lock);
215 	return ret;
216 }
217 
adt7x10_alarm_read(struct adt7x10_data * data,int index,long * val)218 static int adt7x10_alarm_read(struct adt7x10_data *data, int index, long *val)
219 {
220 	unsigned int status;
221 	int ret;
222 
223 	ret = regmap_read(data->regmap, ADT7X10_STATUS, &status);
224 	if (ret < 0)
225 		return ret;
226 
227 	*val = !!(status & index);
228 
229 	return 0;
230 }
231 
adt7x10_is_visible(const void * data,enum hwmon_sensor_types type,u32 attr,int channel)232 static umode_t adt7x10_is_visible(const void *data,
233 				  enum hwmon_sensor_types type,
234 				  u32 attr, int channel)
235 {
236 	switch (attr) {
237 	case hwmon_temp_max:
238 	case hwmon_temp_min:
239 	case hwmon_temp_crit:
240 	case hwmon_temp_max_hyst:
241 		return 0644;
242 	case hwmon_temp_input:
243 	case hwmon_temp_min_alarm:
244 	case hwmon_temp_max_alarm:
245 	case hwmon_temp_crit_alarm:
246 	case hwmon_temp_min_hyst:
247 	case hwmon_temp_crit_hyst:
248 		return 0444;
249 	default:
250 		break;
251 	}
252 
253 	return 0;
254 }
255 
adt7x10_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)256 static int adt7x10_read(struct device *dev, enum hwmon_sensor_types type,
257 			u32 attr, int channel, long *val)
258 {
259 	struct adt7x10_data *data = dev_get_drvdata(dev);
260 
261 	switch (attr) {
262 	case hwmon_temp_input:
263 		return adt7x10_temp_read(data, adt7x10_temperature, val);
264 	case hwmon_temp_max:
265 		return adt7x10_temp_read(data, adt7x10_t_alarm_high, val);
266 	case hwmon_temp_min:
267 		return adt7x10_temp_read(data, adt7x10_t_alarm_low, val);
268 	case hwmon_temp_crit:
269 		return adt7x10_temp_read(data, adt7x10_t_crit, val);
270 	case hwmon_temp_max_hyst:
271 		return adt7x10_hyst_read(data, adt7x10_t_alarm_high, val);
272 	case hwmon_temp_min_hyst:
273 		return adt7x10_hyst_read(data, adt7x10_t_alarm_low, val);
274 	case hwmon_temp_crit_hyst:
275 		return adt7x10_hyst_read(data, adt7x10_t_crit, val);
276 	case hwmon_temp_min_alarm:
277 		return adt7x10_alarm_read(data, ADT7X10_STAT_T_LOW, val);
278 	case hwmon_temp_max_alarm:
279 		return adt7x10_alarm_read(data, ADT7X10_STAT_T_HIGH, val);
280 	case hwmon_temp_crit_alarm:
281 		return adt7x10_alarm_read(data, ADT7X10_STAT_T_CRIT, val);
282 	default:
283 		return -EOPNOTSUPP;
284 	}
285 }
286 
adt7x10_write(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long val)287 static int adt7x10_write(struct device *dev, enum hwmon_sensor_types type,
288 			 u32 attr, int channel, long val)
289 {
290 	struct adt7x10_data *data = dev_get_drvdata(dev);
291 
292 	switch (attr) {
293 	case hwmon_temp_max:
294 		return adt7x10_temp_write(data, adt7x10_t_alarm_high, val);
295 	case hwmon_temp_min:
296 		return adt7x10_temp_write(data, adt7x10_t_alarm_low, val);
297 	case hwmon_temp_crit:
298 		return adt7x10_temp_write(data, adt7x10_t_crit, val);
299 	case hwmon_temp_max_hyst:
300 		return adt7x10_hyst_write(data, val);
301 	default:
302 		return -EOPNOTSUPP;
303 	}
304 }
305 
306 static const struct hwmon_channel_info * const adt7x10_info[] = {
307 	HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN |
308 			   HWMON_T_CRIT | HWMON_T_MAX_HYST | HWMON_T_MIN_HYST |
309 			   HWMON_T_CRIT_HYST | HWMON_T_MIN_ALARM |
310 			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM),
311 	NULL,
312 };
313 
314 static const struct hwmon_ops adt7x10_hwmon_ops = {
315 	.is_visible = adt7x10_is_visible,
316 	.read = adt7x10_read,
317 	.write = adt7x10_write,
318 };
319 
320 static const struct hwmon_chip_info adt7x10_chip_info = {
321 	.ops = &adt7x10_hwmon_ops,
322 	.info = adt7x10_info,
323 };
324 
adt7x10_restore_config(void * private)325 static void adt7x10_restore_config(void *private)
326 {
327 	struct adt7x10_data *data = private;
328 
329 	regmap_write(data->regmap, ADT7X10_CONFIG, data->oldconfig);
330 }
331 
adt7x10_probe(struct device * dev,const char * name,int irq,struct regmap * regmap)332 int adt7x10_probe(struct device *dev, const char *name, int irq,
333 		  struct regmap *regmap)
334 {
335 	struct adt7x10_data *data;
336 	unsigned int config;
337 	struct device *hdev;
338 	int ret;
339 
340 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
341 	if (!data)
342 		return -ENOMEM;
343 
344 	data->regmap = regmap;
345 
346 	dev_set_drvdata(dev, data);
347 	mutex_init(&data->update_lock);
348 
349 	/* configure as specified */
350 	ret = regmap_read(regmap, ADT7X10_CONFIG, &config);
351 	if (ret < 0) {
352 		dev_dbg(dev, "Can't read config? %d\n", ret);
353 		return ret;
354 	}
355 	data->oldconfig = config;
356 
357 	/*
358 	 * Set to 16 bit resolution, continous conversion and comparator mode.
359 	 */
360 	data->config = data->oldconfig;
361 	data->config &= ~(ADT7X10_MODE_MASK | ADT7X10_CT_POLARITY |
362 			ADT7X10_INT_POLARITY);
363 	data->config |= ADT7X10_FULL | ADT7X10_RESOLUTION | ADT7X10_EVENT_MODE;
364 
365 	if (data->config != data->oldconfig) {
366 		ret = regmap_write(regmap, ADT7X10_CONFIG, data->config);
367 		if (ret)
368 			return ret;
369 		ret = devm_add_action_or_reset(dev, adt7x10_restore_config, data);
370 		if (ret)
371 			return ret;
372 	}
373 	dev_dbg(dev, "Config %02x\n", data->config);
374 
375 	hdev = devm_hwmon_device_register_with_info(dev, name, data,
376 						    &adt7x10_chip_info, NULL);
377 	if (IS_ERR(hdev))
378 		return PTR_ERR(hdev);
379 
380 	if (irq > 0) {
381 		ret = devm_request_threaded_irq(dev, irq, NULL,
382 						adt7x10_irq_handler,
383 						IRQF_TRIGGER_FALLING |
384 						IRQF_ONESHOT,
385 						dev_name(dev), hdev);
386 		if (ret)
387 			return ret;
388 	}
389 
390 	return 0;
391 }
392 EXPORT_SYMBOL_GPL(adt7x10_probe);
393 
adt7x10_suspend(struct device * dev)394 static int adt7x10_suspend(struct device *dev)
395 {
396 	struct adt7x10_data *data = dev_get_drvdata(dev);
397 
398 	return regmap_write(data->regmap, ADT7X10_CONFIG,
399 			    data->config | ADT7X10_PD);
400 }
401 
adt7x10_resume(struct device * dev)402 static int adt7x10_resume(struct device *dev)
403 {
404 	struct adt7x10_data *data = dev_get_drvdata(dev);
405 
406 	return regmap_write(data->regmap, ADT7X10_CONFIG, data->config);
407 }
408 
409 EXPORT_SIMPLE_DEV_PM_OPS(adt7x10_dev_pm_ops, adt7x10_suspend, adt7x10_resume);
410 
411 MODULE_AUTHOR("Hartmut Knaack");
412 MODULE_DESCRIPTION("ADT7410/ADT7420, ADT7310/ADT7320 common code");
413 MODULE_LICENSE("GPL");
414