xref: /openbmc/linux/drivers/hwmon/emc6w201.c (revision be709d48)
1 /*
2  * emc6w201.c - Hardware monitoring driver for the SMSC EMC6W201
3  * Copyright (C) 2011  Jean Delvare <jdelvare@suse.de>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18  */
19 
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/slab.h>
23 #include <linux/jiffies.h>
24 #include <linux/i2c.h>
25 #include <linux/hwmon.h>
26 #include <linux/hwmon-sysfs.h>
27 #include <linux/err.h>
28 #include <linux/mutex.h>
29 
30 /*
31  * Addresses to scan
32  */
33 
34 static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, I2C_CLIENT_END };
35 
36 /*
37  * The EMC6W201 registers
38  */
39 
40 #define EMC6W201_REG_IN(nr)		(0x20 + (nr))
41 #define EMC6W201_REG_TEMP(nr)		(0x26 + (nr))
42 #define EMC6W201_REG_FAN(nr)		(0x2C + (nr) * 2)
43 #define EMC6W201_REG_COMPANY		0x3E
44 #define EMC6W201_REG_VERSTEP		0x3F
45 #define EMC6W201_REG_CONFIG		0x40
46 #define EMC6W201_REG_IN_LOW(nr)		(0x4A + (nr) * 2)
47 #define EMC6W201_REG_IN_HIGH(nr)	(0x4B + (nr) * 2)
48 #define EMC6W201_REG_TEMP_LOW(nr)	(0x56 + (nr) * 2)
49 #define EMC6W201_REG_TEMP_HIGH(nr)	(0x57 + (nr) * 2)
50 #define EMC6W201_REG_FAN_MIN(nr)	(0x62 + (nr) * 2)
51 
52 enum subfeature { input, min, max };
53 
54 /*
55  * Per-device data
56  */
57 
58 struct emc6w201_data {
59 	struct i2c_client *client;
60 	struct mutex update_lock;
61 	char valid; /* zero until following fields are valid */
62 	unsigned long last_updated; /* in jiffies */
63 
64 	/* registers values */
65 	u8 in[3][6];
66 	s8 temp[3][6];
67 	u16 fan[2][5];
68 };
69 
70 /*
71  * Combine LSB and MSB registers in a single value
72  * Locking: must be called with data->update_lock held
73  */
74 static u16 emc6w201_read16(struct i2c_client *client, u8 reg)
75 {
76 	int lsb, msb;
77 
78 	lsb = i2c_smbus_read_byte_data(client, reg);
79 	msb = i2c_smbus_read_byte_data(client, reg + 1);
80 	if (unlikely(lsb < 0 || msb < 0)) {
81 		dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n",
82 			16, "read", reg);
83 		return 0xFFFF;	/* Arbitrary value */
84 	}
85 
86 	return (msb << 8) | lsb;
87 }
88 
89 /*
90  * Write 16-bit value to LSB and MSB registers
91  * Locking: must be called with data->update_lock held
92  */
93 static int emc6w201_write16(struct i2c_client *client, u8 reg, u16 val)
94 {
95 	int err;
96 
97 	err = i2c_smbus_write_byte_data(client, reg, val & 0xff);
98 	if (likely(!err))
99 		err = i2c_smbus_write_byte_data(client, reg + 1, val >> 8);
100 	if (unlikely(err < 0))
101 		dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n",
102 			16, "write", reg);
103 
104 	return err;
105 }
106 
107 /* Read 8-bit value from register */
108 static u8 emc6w201_read8(struct i2c_client *client, u8 reg)
109 {
110 	int val;
111 
112 	val = i2c_smbus_read_byte_data(client, reg);
113 	if (unlikely(val < 0)) {
114 		dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n",
115 			8, "read", reg);
116 		return 0x00;	/* Arbitrary value */
117 	}
118 
119 	return val;
120 }
121 
122 /* Write 8-bit value to register */
123 static int emc6w201_write8(struct i2c_client *client, u8 reg, u8 val)
124 {
125 	int err;
126 
127 	err = i2c_smbus_write_byte_data(client, reg, val);
128 	if (unlikely(err < 0))
129 		dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n",
130 			8, "write", reg);
131 
132 	return err;
133 }
134 
135 static struct emc6w201_data *emc6w201_update_device(struct device *dev)
136 {
137 	struct emc6w201_data *data = dev_get_drvdata(dev);
138 	struct i2c_client *client = data->client;
139 	int nr;
140 
141 	mutex_lock(&data->update_lock);
142 
143 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
144 		for (nr = 0; nr < 6; nr++) {
145 			data->in[input][nr] =
146 				emc6w201_read8(client,
147 						EMC6W201_REG_IN(nr));
148 			data->in[min][nr] =
149 				emc6w201_read8(client,
150 						EMC6W201_REG_IN_LOW(nr));
151 			data->in[max][nr] =
152 				emc6w201_read8(client,
153 						EMC6W201_REG_IN_HIGH(nr));
154 		}
155 
156 		for (nr = 0; nr < 6; nr++) {
157 			data->temp[input][nr] =
158 				emc6w201_read8(client,
159 						EMC6W201_REG_TEMP(nr));
160 			data->temp[min][nr] =
161 				emc6w201_read8(client,
162 						EMC6W201_REG_TEMP_LOW(nr));
163 			data->temp[max][nr] =
164 				emc6w201_read8(client,
165 						EMC6W201_REG_TEMP_HIGH(nr));
166 		}
167 
168 		for (nr = 0; nr < 5; nr++) {
169 			data->fan[input][nr] =
170 				emc6w201_read16(client,
171 						EMC6W201_REG_FAN(nr));
172 			data->fan[min][nr] =
173 				emc6w201_read16(client,
174 						EMC6W201_REG_FAN_MIN(nr));
175 		}
176 
177 		data->last_updated = jiffies;
178 		data->valid = 1;
179 	}
180 
181 	mutex_unlock(&data->update_lock);
182 
183 	return data;
184 }
185 
186 /*
187  * Sysfs callback functions
188  */
189 
190 static const s16 nominal_mv[6] = { 2500, 1500, 3300, 5000, 1500, 1500 };
191 
192 static ssize_t in_show(struct device *dev, struct device_attribute *devattr,
193 		       char *buf)
194 {
195 	struct emc6w201_data *data = emc6w201_update_device(dev);
196 	int sf = to_sensor_dev_attr_2(devattr)->index;
197 	int nr = to_sensor_dev_attr_2(devattr)->nr;
198 
199 	return sprintf(buf, "%u\n",
200 		       (unsigned)data->in[sf][nr] * nominal_mv[nr] / 0xC0);
201 }
202 
203 static ssize_t in_store(struct device *dev, struct device_attribute *devattr,
204 			const char *buf, size_t count)
205 {
206 	struct emc6w201_data *data = dev_get_drvdata(dev);
207 	struct i2c_client *client = data->client;
208 	int sf = to_sensor_dev_attr_2(devattr)->index;
209 	int nr = to_sensor_dev_attr_2(devattr)->nr;
210 	int err;
211 	long val;
212 	u8 reg;
213 
214 	err = kstrtol(buf, 10, &val);
215 	if (err < 0)
216 		return err;
217 
218 	val = clamp_val(val, 0, 255 * nominal_mv[nr] / 192);
219 	val = DIV_ROUND_CLOSEST(val * 192, nominal_mv[nr]);
220 	reg = (sf == min) ? EMC6W201_REG_IN_LOW(nr)
221 			  : EMC6W201_REG_IN_HIGH(nr);
222 
223 	mutex_lock(&data->update_lock);
224 	data->in[sf][nr] = val;
225 	err = emc6w201_write8(client, reg, data->in[sf][nr]);
226 	mutex_unlock(&data->update_lock);
227 
228 	return err < 0 ? err : count;
229 }
230 
231 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
232 			 char *buf)
233 {
234 	struct emc6w201_data *data = emc6w201_update_device(dev);
235 	int sf = to_sensor_dev_attr_2(devattr)->index;
236 	int nr = to_sensor_dev_attr_2(devattr)->nr;
237 
238 	return sprintf(buf, "%d\n", (int)data->temp[sf][nr] * 1000);
239 }
240 
241 static ssize_t temp_store(struct device *dev,
242 			  struct device_attribute *devattr, const char *buf,
243 			  size_t count)
244 {
245 	struct emc6w201_data *data = dev_get_drvdata(dev);
246 	struct i2c_client *client = data->client;
247 	int sf = to_sensor_dev_attr_2(devattr)->index;
248 	int nr = to_sensor_dev_attr_2(devattr)->nr;
249 	int err;
250 	long val;
251 	u8 reg;
252 
253 	err = kstrtol(buf, 10, &val);
254 	if (err < 0)
255 		return err;
256 
257 	val = clamp_val(val, -127000, 127000);
258 	val = DIV_ROUND_CLOSEST(val, 1000);
259 	reg = (sf == min) ? EMC6W201_REG_TEMP_LOW(nr)
260 			  : EMC6W201_REG_TEMP_HIGH(nr);
261 
262 	mutex_lock(&data->update_lock);
263 	data->temp[sf][nr] = val;
264 	err = emc6w201_write8(client, reg, data->temp[sf][nr]);
265 	mutex_unlock(&data->update_lock);
266 
267 	return err < 0 ? err : count;
268 }
269 
270 static ssize_t fan_show(struct device *dev, struct device_attribute *devattr,
271 			char *buf)
272 {
273 	struct emc6w201_data *data = emc6w201_update_device(dev);
274 	int sf = to_sensor_dev_attr_2(devattr)->index;
275 	int nr = to_sensor_dev_attr_2(devattr)->nr;
276 	unsigned rpm;
277 
278 	if (data->fan[sf][nr] == 0 || data->fan[sf][nr] == 0xFFFF)
279 		rpm = 0;
280 	else
281 		rpm = 5400000U / data->fan[sf][nr];
282 
283 	return sprintf(buf, "%u\n", rpm);
284 }
285 
286 static ssize_t fan_store(struct device *dev, struct device_attribute *devattr,
287 			 const char *buf, size_t count)
288 {
289 	struct emc6w201_data *data = dev_get_drvdata(dev);
290 	struct i2c_client *client = data->client;
291 	int sf = to_sensor_dev_attr_2(devattr)->index;
292 	int nr = to_sensor_dev_attr_2(devattr)->nr;
293 	int err;
294 	unsigned long val;
295 
296 	err = kstrtoul(buf, 10, &val);
297 	if (err < 0)
298 		return err;
299 
300 	if (val == 0) {
301 		val = 0xFFFF;
302 	} else {
303 		val = DIV_ROUND_CLOSEST(5400000U, val);
304 		val = clamp_val(val, 0, 0xFFFE);
305 	}
306 
307 	mutex_lock(&data->update_lock);
308 	data->fan[sf][nr] = val;
309 	err = emc6w201_write16(client, EMC6W201_REG_FAN_MIN(nr),
310 			       data->fan[sf][nr]);
311 	mutex_unlock(&data->update_lock);
312 
313 	return err < 0 ? err : count;
314 }
315 
316 static SENSOR_DEVICE_ATTR_2_RO(in0_input, in, 0, input);
317 static SENSOR_DEVICE_ATTR_2_RW(in0_min, in, 0, min);
318 static SENSOR_DEVICE_ATTR_2_RW(in0_max, in, 0, max);
319 static SENSOR_DEVICE_ATTR_2_RO(in1_input, in, 1, input);
320 static SENSOR_DEVICE_ATTR_2_RW(in1_min, in, 1, min);
321 static SENSOR_DEVICE_ATTR_2_RW(in1_max, in, 1, max);
322 static SENSOR_DEVICE_ATTR_2_RO(in2_input, in, 2, input);
323 static SENSOR_DEVICE_ATTR_2_RW(in2_min, in, 2, min);
324 static SENSOR_DEVICE_ATTR_2_RW(in2_max, in, 2, max);
325 static SENSOR_DEVICE_ATTR_2_RO(in3_input, in, 3, input);
326 static SENSOR_DEVICE_ATTR_2_RW(in3_min, in, 3, min);
327 static SENSOR_DEVICE_ATTR_2_RW(in3_max, in, 3, max);
328 static SENSOR_DEVICE_ATTR_2_RO(in4_input, in, 4, input);
329 static SENSOR_DEVICE_ATTR_2_RW(in4_min, in, 4, min);
330 static SENSOR_DEVICE_ATTR_2_RW(in4_max, in, 4, max);
331 static SENSOR_DEVICE_ATTR_2_RO(in5_input, in, 5, input);
332 static SENSOR_DEVICE_ATTR_2_RW(in5_min, in, 5, min);
333 static SENSOR_DEVICE_ATTR_2_RW(in5_max, in, 5, max);
334 
335 static SENSOR_DEVICE_ATTR_2_RO(temp1_input, temp, 0, input);
336 static SENSOR_DEVICE_ATTR_2_RW(temp1_min, temp, 0, min);
337 static SENSOR_DEVICE_ATTR_2_RW(temp1_max, temp, 0, max);
338 static SENSOR_DEVICE_ATTR_2_RO(temp2_input, temp, 1, input);
339 static SENSOR_DEVICE_ATTR_2_RW(temp2_min, temp, 1, min);
340 static SENSOR_DEVICE_ATTR_2_RW(temp2_max, temp, 1, max);
341 static SENSOR_DEVICE_ATTR_2_RO(temp3_input, temp, 2, input);
342 static SENSOR_DEVICE_ATTR_2_RW(temp3_min, temp, 2, min);
343 static SENSOR_DEVICE_ATTR_2_RW(temp3_max, temp, 2, max);
344 static SENSOR_DEVICE_ATTR_2_RO(temp4_input, temp, 3, input);
345 static SENSOR_DEVICE_ATTR_2_RW(temp4_min, temp, 3, min);
346 static SENSOR_DEVICE_ATTR_2_RW(temp4_max, temp, 3, max);
347 static SENSOR_DEVICE_ATTR_2_RO(temp5_input, temp, 4, input);
348 static SENSOR_DEVICE_ATTR_2_RW(temp5_min, temp, 4, min);
349 static SENSOR_DEVICE_ATTR_2_RW(temp5_max, temp, 4, max);
350 static SENSOR_DEVICE_ATTR_2_RO(temp6_input, temp, 5, input);
351 static SENSOR_DEVICE_ATTR_2_RW(temp6_min, temp, 5, min);
352 static SENSOR_DEVICE_ATTR_2_RW(temp6_max, temp, 5, max);
353 
354 static SENSOR_DEVICE_ATTR_2_RO(fan1_input, fan, 0, input);
355 static SENSOR_DEVICE_ATTR_2_RW(fan1_min, fan, 0, min);
356 static SENSOR_DEVICE_ATTR_2_RO(fan2_input, fan, 1, input);
357 static SENSOR_DEVICE_ATTR_2_RW(fan2_min, fan, 1, min);
358 static SENSOR_DEVICE_ATTR_2_RO(fan3_input, fan, 2, input);
359 static SENSOR_DEVICE_ATTR_2_RW(fan3_min, fan, 2, min);
360 static SENSOR_DEVICE_ATTR_2_RO(fan4_input, fan, 3, input);
361 static SENSOR_DEVICE_ATTR_2_RW(fan4_min, fan, 3, min);
362 static SENSOR_DEVICE_ATTR_2_RO(fan5_input, fan, 4, input);
363 static SENSOR_DEVICE_ATTR_2_RW(fan5_min, fan, 4, min);
364 
365 static struct attribute *emc6w201_attrs[] = {
366 	&sensor_dev_attr_in0_input.dev_attr.attr,
367 	&sensor_dev_attr_in0_min.dev_attr.attr,
368 	&sensor_dev_attr_in0_max.dev_attr.attr,
369 	&sensor_dev_attr_in1_input.dev_attr.attr,
370 	&sensor_dev_attr_in1_min.dev_attr.attr,
371 	&sensor_dev_attr_in1_max.dev_attr.attr,
372 	&sensor_dev_attr_in2_input.dev_attr.attr,
373 	&sensor_dev_attr_in2_min.dev_attr.attr,
374 	&sensor_dev_attr_in2_max.dev_attr.attr,
375 	&sensor_dev_attr_in3_input.dev_attr.attr,
376 	&sensor_dev_attr_in3_min.dev_attr.attr,
377 	&sensor_dev_attr_in3_max.dev_attr.attr,
378 	&sensor_dev_attr_in4_input.dev_attr.attr,
379 	&sensor_dev_attr_in4_min.dev_attr.attr,
380 	&sensor_dev_attr_in4_max.dev_attr.attr,
381 	&sensor_dev_attr_in5_input.dev_attr.attr,
382 	&sensor_dev_attr_in5_min.dev_attr.attr,
383 	&sensor_dev_attr_in5_max.dev_attr.attr,
384 
385 	&sensor_dev_attr_temp1_input.dev_attr.attr,
386 	&sensor_dev_attr_temp1_min.dev_attr.attr,
387 	&sensor_dev_attr_temp1_max.dev_attr.attr,
388 	&sensor_dev_attr_temp2_input.dev_attr.attr,
389 	&sensor_dev_attr_temp2_min.dev_attr.attr,
390 	&sensor_dev_attr_temp2_max.dev_attr.attr,
391 	&sensor_dev_attr_temp3_input.dev_attr.attr,
392 	&sensor_dev_attr_temp3_min.dev_attr.attr,
393 	&sensor_dev_attr_temp3_max.dev_attr.attr,
394 	&sensor_dev_attr_temp4_input.dev_attr.attr,
395 	&sensor_dev_attr_temp4_min.dev_attr.attr,
396 	&sensor_dev_attr_temp4_max.dev_attr.attr,
397 	&sensor_dev_attr_temp5_input.dev_attr.attr,
398 	&sensor_dev_attr_temp5_min.dev_attr.attr,
399 	&sensor_dev_attr_temp5_max.dev_attr.attr,
400 	&sensor_dev_attr_temp6_input.dev_attr.attr,
401 	&sensor_dev_attr_temp6_min.dev_attr.attr,
402 	&sensor_dev_attr_temp6_max.dev_attr.attr,
403 
404 	&sensor_dev_attr_fan1_input.dev_attr.attr,
405 	&sensor_dev_attr_fan1_min.dev_attr.attr,
406 	&sensor_dev_attr_fan2_input.dev_attr.attr,
407 	&sensor_dev_attr_fan2_min.dev_attr.attr,
408 	&sensor_dev_attr_fan3_input.dev_attr.attr,
409 	&sensor_dev_attr_fan3_min.dev_attr.attr,
410 	&sensor_dev_attr_fan4_input.dev_attr.attr,
411 	&sensor_dev_attr_fan4_min.dev_attr.attr,
412 	&sensor_dev_attr_fan5_input.dev_attr.attr,
413 	&sensor_dev_attr_fan5_min.dev_attr.attr,
414 	NULL
415 };
416 
417 ATTRIBUTE_GROUPS(emc6w201);
418 
419 /*
420  * Driver interface
421  */
422 
423 /* Return 0 if detection is successful, -ENODEV otherwise */
424 static int emc6w201_detect(struct i2c_client *client,
425 			   struct i2c_board_info *info)
426 {
427 	struct i2c_adapter *adapter = client->adapter;
428 	int company, verstep, config;
429 
430 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
431 		return -ENODEV;
432 
433 	/* Identification */
434 	company = i2c_smbus_read_byte_data(client, EMC6W201_REG_COMPANY);
435 	if (company != 0x5C)
436 		return -ENODEV;
437 	verstep = i2c_smbus_read_byte_data(client, EMC6W201_REG_VERSTEP);
438 	if (verstep < 0 || (verstep & 0xF0) != 0xB0)
439 		return -ENODEV;
440 	if ((verstep & 0x0F) > 2) {
441 		dev_dbg(&client->dev, "Unknown EMC6W201 stepping %d\n",
442 			verstep & 0x0F);
443 		return -ENODEV;
444 	}
445 
446 	/* Check configuration */
447 	config = i2c_smbus_read_byte_data(client, EMC6W201_REG_CONFIG);
448 	if (config < 0 || (config & 0xF4) != 0x04)
449 		return -ENODEV;
450 	if (!(config & 0x01)) {
451 		dev_err(&client->dev, "Monitoring not enabled\n");
452 		return -ENODEV;
453 	}
454 
455 	strlcpy(info->type, "emc6w201", I2C_NAME_SIZE);
456 
457 	return 0;
458 }
459 
460 static int emc6w201_probe(struct i2c_client *client,
461 			  const struct i2c_device_id *id)
462 {
463 	struct device *dev = &client->dev;
464 	struct emc6w201_data *data;
465 	struct device *hwmon_dev;
466 
467 	data = devm_kzalloc(dev, sizeof(struct emc6w201_data), GFP_KERNEL);
468 	if (!data)
469 		return -ENOMEM;
470 
471 	data->client = client;
472 	mutex_init(&data->update_lock);
473 
474 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
475 							   data,
476 							   emc6w201_groups);
477 	return PTR_ERR_OR_ZERO(hwmon_dev);
478 }
479 
480 static const struct i2c_device_id emc6w201_id[] = {
481 	{ "emc6w201", 0 },
482 	{ }
483 };
484 MODULE_DEVICE_TABLE(i2c, emc6w201_id);
485 
486 static struct i2c_driver emc6w201_driver = {
487 	.class		= I2C_CLASS_HWMON,
488 	.driver = {
489 		.name	= "emc6w201",
490 	},
491 	.probe		= emc6w201_probe,
492 	.id_table	= emc6w201_id,
493 	.detect		= emc6w201_detect,
494 	.address_list	= normal_i2c,
495 };
496 
497 module_i2c_driver(emc6w201_driver);
498 
499 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
500 MODULE_DESCRIPTION("SMSC EMC6W201 hardware monitoring driver");
501 MODULE_LICENSE("GPL");
502