xref: /openbmc/linux/drivers/hwmon/lineage-pem.c (revision 95e9fd10)
1 /*
2  * Driver for Lineage Compact Power Line series of power entry modules.
3  *
4  * Copyright (C) 2010, 2011 Ericsson AB.
5  *
6  * Documentation:
7  *  http://www.lineagepower.com/oem/pdf/CPLI2C.pdf
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  */
23 
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/err.h>
28 #include <linux/slab.h>
29 #include <linux/i2c.h>
30 #include <linux/hwmon.h>
31 #include <linux/hwmon-sysfs.h>
32 
33 /*
34  * This driver supports various Lineage Compact Power Line DC/DC and AC/DC
35  * converters such as CP1800, CP2000AC, CP2000DC, CP2100DC, and others.
36  *
37  * The devices are nominally PMBus compliant. However, most standard PMBus
38  * commands are not supported. Specifically, all hardware monitoring and
39  * status reporting commands are non-standard. For this reason, a standard
40  * PMBus driver can not be used.
41  *
42  * All Lineage CPL devices have a built-in I2C bus master selector (PCA9541).
43  * To ensure device access, this driver should only be used as client driver
44  * to the pca9541 I2C master selector driver.
45  */
46 
47 /* Command codes */
48 #define PEM_OPERATION		0x01
49 #define PEM_CLEAR_INFO_FLAGS	0x03
50 #define PEM_VOUT_COMMAND	0x21
51 #define PEM_VOUT_OV_FAULT_LIMIT	0x40
52 #define PEM_READ_DATA_STRING	0xd0
53 #define PEM_READ_INPUT_STRING	0xdc
54 #define PEM_READ_FIRMWARE_REV	0xdd
55 #define PEM_READ_RUN_TIMER	0xde
56 #define PEM_FAN_HI_SPEED	0xdf
57 #define PEM_FAN_NORMAL_SPEED	0xe0
58 #define PEM_READ_FAN_SPEED	0xe1
59 
60 /* offsets in data string */
61 #define PEM_DATA_STATUS_2	0
62 #define PEM_DATA_STATUS_1	1
63 #define PEM_DATA_ALARM_2	2
64 #define PEM_DATA_ALARM_1	3
65 #define PEM_DATA_VOUT_LSB	4
66 #define PEM_DATA_VOUT_MSB	5
67 #define PEM_DATA_CURRENT	6
68 #define PEM_DATA_TEMP		7
69 
70 /* Virtual entries, to report constants */
71 #define PEM_DATA_TEMP_MAX	10
72 #define PEM_DATA_TEMP_CRIT	11
73 
74 /* offsets in input string */
75 #define PEM_INPUT_VOLTAGE	0
76 #define PEM_INPUT_POWER_LSB	1
77 #define PEM_INPUT_POWER_MSB	2
78 
79 /* offsets in fan data */
80 #define PEM_FAN_ADJUSTMENT	0
81 #define PEM_FAN_FAN1		1
82 #define PEM_FAN_FAN2		2
83 #define PEM_FAN_FAN3		3
84 
85 /* Status register bits */
86 #define STS1_OUTPUT_ON		(1 << 0)
87 #define STS1_LEDS_FLASHING	(1 << 1)
88 #define STS1_EXT_FAULT		(1 << 2)
89 #define STS1_SERVICE_LED_ON	(1 << 3)
90 #define STS1_SHUTDOWN_OCCURRED	(1 << 4)
91 #define STS1_INT_FAULT		(1 << 5)
92 #define STS1_ISOLATION_TEST_OK	(1 << 6)
93 
94 #define STS2_ENABLE_PIN_HI	(1 << 0)
95 #define STS2_DATA_OUT_RANGE	(1 << 1)
96 #define STS2_RESTARTED_OK	(1 << 1)
97 #define STS2_ISOLATION_TEST_FAIL (1 << 3)
98 #define STS2_HIGH_POWER_CAP	(1 << 4)
99 #define STS2_INVALID_INSTR	(1 << 5)
100 #define STS2_WILL_RESTART	(1 << 6)
101 #define STS2_PEC_ERR		(1 << 7)
102 
103 /* Alarm register bits */
104 #define ALRM1_VIN_OUT_LIMIT	(1 << 0)
105 #define ALRM1_VOUT_OUT_LIMIT	(1 << 1)
106 #define ALRM1_OV_VOLT_SHUTDOWN	(1 << 2)
107 #define ALRM1_VIN_OVERCURRENT	(1 << 3)
108 #define ALRM1_TEMP_WARNING	(1 << 4)
109 #define ALRM1_TEMP_SHUTDOWN	(1 << 5)
110 #define ALRM1_PRIMARY_FAULT	(1 << 6)
111 #define ALRM1_POWER_LIMIT	(1 << 7)
112 
113 #define ALRM2_5V_OUT_LIMIT	(1 << 1)
114 #define ALRM2_TEMP_FAULT	(1 << 2)
115 #define ALRM2_OV_LOW		(1 << 3)
116 #define ALRM2_DCDC_TEMP_HIGH	(1 << 4)
117 #define ALRM2_PRI_TEMP_HIGH	(1 << 5)
118 #define ALRM2_NO_PRIMARY	(1 << 6)
119 #define ALRM2_FAN_FAULT		(1 << 7)
120 
121 #define FIRMWARE_REV_LEN	4
122 #define DATA_STRING_LEN		9
123 #define INPUT_STRING_LEN	5	/* 4 for most devices	*/
124 #define FAN_SPEED_LEN		5
125 
126 struct pem_data {
127 	struct device *hwmon_dev;
128 
129 	struct mutex update_lock;
130 	bool valid;
131 	bool fans_supported;
132 	int input_length;
133 	unsigned long last_updated;	/* in jiffies */
134 
135 	u8 firmware_rev[FIRMWARE_REV_LEN];
136 	u8 data_string[DATA_STRING_LEN];
137 	u8 input_string[INPUT_STRING_LEN];
138 	u8 fan_speed[FAN_SPEED_LEN];
139 };
140 
141 static int pem_read_block(struct i2c_client *client, u8 command, u8 *data,
142 			  int data_len)
143 {
144 	u8 block_buffer[I2C_SMBUS_BLOCK_MAX];
145 	int result;
146 
147 	result = i2c_smbus_read_block_data(client, command, block_buffer);
148 	if (unlikely(result < 0))
149 		goto abort;
150 	if (unlikely(result == 0xff || result != data_len)) {
151 		result = -EIO;
152 		goto abort;
153 	}
154 	memcpy(data, block_buffer, data_len);
155 	result = 0;
156 abort:
157 	return result;
158 }
159 
160 static struct pem_data *pem_update_device(struct device *dev)
161 {
162 	struct i2c_client *client = to_i2c_client(dev);
163 	struct pem_data *data = i2c_get_clientdata(client);
164 	struct pem_data *ret = data;
165 
166 	mutex_lock(&data->update_lock);
167 
168 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
169 		int result;
170 
171 		/* Read data string */
172 		result = pem_read_block(client, PEM_READ_DATA_STRING,
173 					data->data_string,
174 					sizeof(data->data_string));
175 		if (unlikely(result < 0)) {
176 			ret = ERR_PTR(result);
177 			goto abort;
178 		}
179 
180 		/* Read input string */
181 		if (data->input_length) {
182 			result = pem_read_block(client, PEM_READ_INPUT_STRING,
183 						data->input_string,
184 						data->input_length);
185 			if (unlikely(result < 0)) {
186 				ret = ERR_PTR(result);
187 				goto abort;
188 			}
189 		}
190 
191 		/* Read fan speeds */
192 		if (data->fans_supported) {
193 			result = pem_read_block(client, PEM_READ_FAN_SPEED,
194 						data->fan_speed,
195 						sizeof(data->fan_speed));
196 			if (unlikely(result < 0)) {
197 				ret = ERR_PTR(result);
198 				goto abort;
199 			}
200 		}
201 
202 		i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
203 
204 		data->last_updated = jiffies;
205 		data->valid = 1;
206 	}
207 abort:
208 	mutex_unlock(&data->update_lock);
209 	return ret;
210 }
211 
212 static long pem_get_data(u8 *data, int len, int index)
213 {
214 	long val;
215 
216 	switch (index) {
217 	case PEM_DATA_VOUT_LSB:
218 		val = (data[index] + (data[index+1] << 8)) * 5 / 2;
219 		break;
220 	case PEM_DATA_CURRENT:
221 		val = data[index] * 200;
222 		break;
223 	case PEM_DATA_TEMP:
224 		val = data[index] * 1000;
225 		break;
226 	case PEM_DATA_TEMP_MAX:
227 		val = 97 * 1000;	/* 97 degrees C per datasheet */
228 		break;
229 	case PEM_DATA_TEMP_CRIT:
230 		val = 107 * 1000;	/* 107 degrees C per datasheet */
231 		break;
232 	default:
233 		WARN_ON_ONCE(1);
234 		val = 0;
235 	}
236 	return val;
237 }
238 
239 static long pem_get_input(u8 *data, int len, int index)
240 {
241 	long val;
242 
243 	switch (index) {
244 	case PEM_INPUT_VOLTAGE:
245 		if (len == INPUT_STRING_LEN)
246 			val = (data[index] + (data[index+1] << 8) - 75) * 1000;
247 		else
248 			val = (data[index] - 75) * 1000;
249 		break;
250 	case PEM_INPUT_POWER_LSB:
251 		if (len == INPUT_STRING_LEN)
252 			index++;
253 		val = (data[index] + (data[index+1] << 8)) * 1000000L;
254 		break;
255 	default:
256 		WARN_ON_ONCE(1);
257 		val = 0;
258 	}
259 	return val;
260 }
261 
262 static long pem_get_fan(u8 *data, int len, int index)
263 {
264 	long val;
265 
266 	switch (index) {
267 	case PEM_FAN_FAN1:
268 	case PEM_FAN_FAN2:
269 	case PEM_FAN_FAN3:
270 		val = data[index] * 100;
271 		break;
272 	default:
273 		WARN_ON_ONCE(1);
274 		val = 0;
275 	}
276 	return val;
277 }
278 
279 /*
280  * Show boolean, either a fault or an alarm.
281  * .nr points to the register, .index is the bit mask to check
282  */
283 static ssize_t pem_show_bool(struct device *dev,
284 			     struct device_attribute *da, char *buf)
285 {
286 	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
287 	struct pem_data *data = pem_update_device(dev);
288 	u8 status;
289 
290 	if (IS_ERR(data))
291 		return PTR_ERR(data);
292 
293 	status = data->data_string[attr->nr] & attr->index;
294 	return snprintf(buf, PAGE_SIZE, "%d\n", !!status);
295 }
296 
297 static ssize_t pem_show_data(struct device *dev, struct device_attribute *da,
298 			     char *buf)
299 {
300 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
301 	struct pem_data *data = pem_update_device(dev);
302 	long value;
303 
304 	if (IS_ERR(data))
305 		return PTR_ERR(data);
306 
307 	value = pem_get_data(data->data_string, sizeof(data->data_string),
308 			     attr->index);
309 
310 	return snprintf(buf, PAGE_SIZE, "%ld\n", value);
311 }
312 
313 static ssize_t pem_show_input(struct device *dev, struct device_attribute *da,
314 			      char *buf)
315 {
316 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
317 	struct pem_data *data = pem_update_device(dev);
318 	long value;
319 
320 	if (IS_ERR(data))
321 		return PTR_ERR(data);
322 
323 	value = pem_get_input(data->input_string, sizeof(data->input_string),
324 			      attr->index);
325 
326 	return snprintf(buf, PAGE_SIZE, "%ld\n", value);
327 }
328 
329 static ssize_t pem_show_fan(struct device *dev, struct device_attribute *da,
330 			    char *buf)
331 {
332 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
333 	struct pem_data *data = pem_update_device(dev);
334 	long value;
335 
336 	if (IS_ERR(data))
337 		return PTR_ERR(data);
338 
339 	value = pem_get_fan(data->fan_speed, sizeof(data->fan_speed),
340 			    attr->index);
341 
342 	return snprintf(buf, PAGE_SIZE, "%ld\n", value);
343 }
344 
345 /* Voltages */
346 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, pem_show_data, NULL,
347 			  PEM_DATA_VOUT_LSB);
348 static SENSOR_DEVICE_ATTR_2(in1_alarm, S_IRUGO, pem_show_bool, NULL,
349 			    PEM_DATA_ALARM_1, ALRM1_VOUT_OUT_LIMIT);
350 static SENSOR_DEVICE_ATTR_2(in1_crit_alarm, S_IRUGO, pem_show_bool, NULL,
351 			    PEM_DATA_ALARM_1, ALRM1_OV_VOLT_SHUTDOWN);
352 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, pem_show_input, NULL,
353 			  PEM_INPUT_VOLTAGE);
354 static SENSOR_DEVICE_ATTR_2(in2_alarm, S_IRUGO, pem_show_bool, NULL,
355 			    PEM_DATA_ALARM_1,
356 			    ALRM1_VIN_OUT_LIMIT | ALRM1_PRIMARY_FAULT);
357 
358 /* Currents */
359 static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, pem_show_data, NULL,
360 			  PEM_DATA_CURRENT);
361 static SENSOR_DEVICE_ATTR_2(curr1_alarm, S_IRUGO, pem_show_bool, NULL,
362 			    PEM_DATA_ALARM_1, ALRM1_VIN_OVERCURRENT);
363 
364 /* Power */
365 static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, pem_show_input, NULL,
366 			  PEM_INPUT_POWER_LSB);
367 static SENSOR_DEVICE_ATTR_2(power1_alarm, S_IRUGO, pem_show_bool, NULL,
368 			    PEM_DATA_ALARM_1, ALRM1_POWER_LIMIT);
369 
370 /* Fans */
371 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, pem_show_fan, NULL,
372 			  PEM_FAN_FAN1);
373 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, pem_show_fan, NULL,
374 			  PEM_FAN_FAN2);
375 static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, pem_show_fan, NULL,
376 			  PEM_FAN_FAN3);
377 static SENSOR_DEVICE_ATTR_2(fan1_alarm, S_IRUGO, pem_show_bool, NULL,
378 			    PEM_DATA_ALARM_2, ALRM2_FAN_FAULT);
379 
380 /* Temperatures */
381 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, pem_show_data, NULL,
382 			  PEM_DATA_TEMP);
383 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, pem_show_data, NULL,
384 			  PEM_DATA_TEMP_MAX);
385 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, pem_show_data, NULL,
386 			  PEM_DATA_TEMP_CRIT);
387 static SENSOR_DEVICE_ATTR_2(temp1_alarm, S_IRUGO, pem_show_bool, NULL,
388 			    PEM_DATA_ALARM_1, ALRM1_TEMP_WARNING);
389 static SENSOR_DEVICE_ATTR_2(temp1_crit_alarm, S_IRUGO, pem_show_bool, NULL,
390 			    PEM_DATA_ALARM_1, ALRM1_TEMP_SHUTDOWN);
391 static SENSOR_DEVICE_ATTR_2(temp1_fault, S_IRUGO, pem_show_bool, NULL,
392 			    PEM_DATA_ALARM_2, ALRM2_TEMP_FAULT);
393 
394 static struct attribute *pem_attributes[] = {
395 	&sensor_dev_attr_in1_input.dev_attr.attr,
396 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
397 	&sensor_dev_attr_in1_crit_alarm.dev_attr.attr,
398 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
399 
400 	&sensor_dev_attr_curr1_alarm.dev_attr.attr,
401 
402 	&sensor_dev_attr_power1_alarm.dev_attr.attr,
403 
404 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
405 
406 	&sensor_dev_attr_temp1_input.dev_attr.attr,
407 	&sensor_dev_attr_temp1_max.dev_attr.attr,
408 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
409 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
410 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
411 	&sensor_dev_attr_temp1_fault.dev_attr.attr,
412 
413 	NULL,
414 };
415 
416 static const struct attribute_group pem_group = {
417 	.attrs = pem_attributes,
418 };
419 
420 static struct attribute *pem_input_attributes[] = {
421 	&sensor_dev_attr_in2_input.dev_attr.attr,
422 	&sensor_dev_attr_curr1_input.dev_attr.attr,
423 	&sensor_dev_attr_power1_input.dev_attr.attr,
424 };
425 
426 static const struct attribute_group pem_input_group = {
427 	.attrs = pem_input_attributes,
428 };
429 
430 static struct attribute *pem_fan_attributes[] = {
431 	&sensor_dev_attr_fan1_input.dev_attr.attr,
432 	&sensor_dev_attr_fan2_input.dev_attr.attr,
433 	&sensor_dev_attr_fan3_input.dev_attr.attr,
434 };
435 
436 static const struct attribute_group pem_fan_group = {
437 	.attrs = pem_fan_attributes,
438 };
439 
440 static int pem_probe(struct i2c_client *client,
441 		     const struct i2c_device_id *id)
442 {
443 	struct i2c_adapter *adapter = client->adapter;
444 	struct pem_data *data;
445 	int ret;
446 
447 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BLOCK_DATA
448 				     | I2C_FUNC_SMBUS_WRITE_BYTE))
449 		return -ENODEV;
450 
451 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
452 	if (!data)
453 		return -ENOMEM;
454 
455 	i2c_set_clientdata(client, data);
456 	mutex_init(&data->update_lock);
457 
458 	/*
459 	 * We use the next two commands to determine if the device is really
460 	 * there.
461 	 */
462 	ret = pem_read_block(client, PEM_READ_FIRMWARE_REV,
463 			     data->firmware_rev, sizeof(data->firmware_rev));
464 	if (ret < 0)
465 		return ret;
466 
467 	ret = i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
468 	if (ret < 0)
469 		return ret;
470 
471 	dev_info(&client->dev, "Firmware revision %d.%d.%d\n",
472 		 data->firmware_rev[0], data->firmware_rev[1],
473 		 data->firmware_rev[2]);
474 
475 	/* Register sysfs hooks */
476 	ret = sysfs_create_group(&client->dev.kobj, &pem_group);
477 	if (ret)
478 		return ret;
479 
480 	/*
481 	 * Check if input readings are supported.
482 	 * This is the case if we can read input data,
483 	 * and if the returned data is not all zeros.
484 	 * Note that input alarms are always supported.
485 	 */
486 	ret = pem_read_block(client, PEM_READ_INPUT_STRING,
487 			     data->input_string,
488 			     sizeof(data->input_string) - 1);
489 	if (!ret && (data->input_string[0] || data->input_string[1] ||
490 		     data->input_string[2]))
491 		data->input_length = sizeof(data->input_string) - 1;
492 	else if (ret < 0) {
493 		/* Input string is one byte longer for some devices */
494 		ret = pem_read_block(client, PEM_READ_INPUT_STRING,
495 				    data->input_string,
496 				    sizeof(data->input_string));
497 		if (!ret && (data->input_string[0] || data->input_string[1] ||
498 			    data->input_string[2] || data->input_string[3]))
499 			data->input_length = sizeof(data->input_string);
500 	}
501 	ret = 0;
502 	if (data->input_length) {
503 		ret = sysfs_create_group(&client->dev.kobj, &pem_input_group);
504 		if (ret)
505 			goto out_remove_groups;
506 	}
507 
508 	/*
509 	 * Check if fan speed readings are supported.
510 	 * This is the case if we can read fan speed data,
511 	 * and if the returned data is not all zeros.
512 	 * Note that the fan alarm is always supported.
513 	 */
514 	ret = pem_read_block(client, PEM_READ_FAN_SPEED,
515 			     data->fan_speed,
516 			     sizeof(data->fan_speed));
517 	if (!ret && (data->fan_speed[0] || data->fan_speed[1] ||
518 		     data->fan_speed[2] || data->fan_speed[3])) {
519 		data->fans_supported = true;
520 		ret = sysfs_create_group(&client->dev.kobj, &pem_fan_group);
521 		if (ret)
522 			goto out_remove_groups;
523 	}
524 
525 	data->hwmon_dev = hwmon_device_register(&client->dev);
526 	if (IS_ERR(data->hwmon_dev)) {
527 		ret = PTR_ERR(data->hwmon_dev);
528 		goto out_remove_groups;
529 	}
530 
531 	return 0;
532 
533 out_remove_groups:
534 	sysfs_remove_group(&client->dev.kobj, &pem_input_group);
535 	sysfs_remove_group(&client->dev.kobj, &pem_fan_group);
536 	sysfs_remove_group(&client->dev.kobj, &pem_group);
537 	return ret;
538 }
539 
540 static int pem_remove(struct i2c_client *client)
541 {
542 	struct pem_data *data = i2c_get_clientdata(client);
543 
544 	hwmon_device_unregister(data->hwmon_dev);
545 
546 	sysfs_remove_group(&client->dev.kobj, &pem_input_group);
547 	sysfs_remove_group(&client->dev.kobj, &pem_fan_group);
548 	sysfs_remove_group(&client->dev.kobj, &pem_group);
549 
550 	return 0;
551 }
552 
553 static const struct i2c_device_id pem_id[] = {
554 	{"lineage_pem", 0},
555 	{}
556 };
557 MODULE_DEVICE_TABLE(i2c, pem_id);
558 
559 static struct i2c_driver pem_driver = {
560 	.driver = {
561 		   .name = "lineage_pem",
562 		   },
563 	.probe = pem_probe,
564 	.remove = pem_remove,
565 	.id_table = pem_id,
566 };
567 
568 module_i2c_driver(pem_driver);
569 
570 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
571 MODULE_DESCRIPTION("Lineage CPL PEM hardware monitoring driver");
572 MODULE_LICENSE("GPL");
573