xref: /openbmc/linux/drivers/hwmon/lineage-pem.c (revision c4ee0af3)
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 #include <linux/jiffies.h>
33 
34 /*
35  * This driver supports various Lineage Compact Power Line DC/DC and AC/DC
36  * converters such as CP1800, CP2000AC, CP2000DC, CP2100DC, and others.
37  *
38  * The devices are nominally PMBus compliant. However, most standard PMBus
39  * commands are not supported. Specifically, all hardware monitoring and
40  * status reporting commands are non-standard. For this reason, a standard
41  * PMBus driver can not be used.
42  *
43  * All Lineage CPL devices have a built-in I2C bus master selector (PCA9541).
44  * To ensure device access, this driver should only be used as client driver
45  * to the pca9541 I2C master selector driver.
46  */
47 
48 /* Command codes */
49 #define PEM_OPERATION		0x01
50 #define PEM_CLEAR_INFO_FLAGS	0x03
51 #define PEM_VOUT_COMMAND	0x21
52 #define PEM_VOUT_OV_FAULT_LIMIT	0x40
53 #define PEM_READ_DATA_STRING	0xd0
54 #define PEM_READ_INPUT_STRING	0xdc
55 #define PEM_READ_FIRMWARE_REV	0xdd
56 #define PEM_READ_RUN_TIMER	0xde
57 #define PEM_FAN_HI_SPEED	0xdf
58 #define PEM_FAN_NORMAL_SPEED	0xe0
59 #define PEM_READ_FAN_SPEED	0xe1
60 
61 /* offsets in data string */
62 #define PEM_DATA_STATUS_2	0
63 #define PEM_DATA_STATUS_1	1
64 #define PEM_DATA_ALARM_2	2
65 #define PEM_DATA_ALARM_1	3
66 #define PEM_DATA_VOUT_LSB	4
67 #define PEM_DATA_VOUT_MSB	5
68 #define PEM_DATA_CURRENT	6
69 #define PEM_DATA_TEMP		7
70 
71 /* Virtual entries, to report constants */
72 #define PEM_DATA_TEMP_MAX	10
73 #define PEM_DATA_TEMP_CRIT	11
74 
75 /* offsets in input string */
76 #define PEM_INPUT_VOLTAGE	0
77 #define PEM_INPUT_POWER_LSB	1
78 #define PEM_INPUT_POWER_MSB	2
79 
80 /* offsets in fan data */
81 #define PEM_FAN_ADJUSTMENT	0
82 #define PEM_FAN_FAN1		1
83 #define PEM_FAN_FAN2		2
84 #define PEM_FAN_FAN3		3
85 
86 /* Status register bits */
87 #define STS1_OUTPUT_ON		(1 << 0)
88 #define STS1_LEDS_FLASHING	(1 << 1)
89 #define STS1_EXT_FAULT		(1 << 2)
90 #define STS1_SERVICE_LED_ON	(1 << 3)
91 #define STS1_SHUTDOWN_OCCURRED	(1 << 4)
92 #define STS1_INT_FAULT		(1 << 5)
93 #define STS1_ISOLATION_TEST_OK	(1 << 6)
94 
95 #define STS2_ENABLE_PIN_HI	(1 << 0)
96 #define STS2_DATA_OUT_RANGE	(1 << 1)
97 #define STS2_RESTARTED_OK	(1 << 1)
98 #define STS2_ISOLATION_TEST_FAIL (1 << 3)
99 #define STS2_HIGH_POWER_CAP	(1 << 4)
100 #define STS2_INVALID_INSTR	(1 << 5)
101 #define STS2_WILL_RESTART	(1 << 6)
102 #define STS2_PEC_ERR		(1 << 7)
103 
104 /* Alarm register bits */
105 #define ALRM1_VIN_OUT_LIMIT	(1 << 0)
106 #define ALRM1_VOUT_OUT_LIMIT	(1 << 1)
107 #define ALRM1_OV_VOLT_SHUTDOWN	(1 << 2)
108 #define ALRM1_VIN_OVERCURRENT	(1 << 3)
109 #define ALRM1_TEMP_WARNING	(1 << 4)
110 #define ALRM1_TEMP_SHUTDOWN	(1 << 5)
111 #define ALRM1_PRIMARY_FAULT	(1 << 6)
112 #define ALRM1_POWER_LIMIT	(1 << 7)
113 
114 #define ALRM2_5V_OUT_LIMIT	(1 << 1)
115 #define ALRM2_TEMP_FAULT	(1 << 2)
116 #define ALRM2_OV_LOW		(1 << 3)
117 #define ALRM2_DCDC_TEMP_HIGH	(1 << 4)
118 #define ALRM2_PRI_TEMP_HIGH	(1 << 5)
119 #define ALRM2_NO_PRIMARY	(1 << 6)
120 #define ALRM2_FAN_FAULT		(1 << 7)
121 
122 #define FIRMWARE_REV_LEN	4
123 #define DATA_STRING_LEN		9
124 #define INPUT_STRING_LEN	5	/* 4 for most devices	*/
125 #define FAN_SPEED_LEN		5
126 
127 struct pem_data {
128 	struct device *hwmon_dev;
129 
130 	struct mutex update_lock;
131 	bool valid;
132 	bool fans_supported;
133 	int input_length;
134 	unsigned long last_updated;	/* in jiffies */
135 
136 	u8 firmware_rev[FIRMWARE_REV_LEN];
137 	u8 data_string[DATA_STRING_LEN];
138 	u8 input_string[INPUT_STRING_LEN];
139 	u8 fan_speed[FAN_SPEED_LEN];
140 };
141 
142 static int pem_read_block(struct i2c_client *client, u8 command, u8 *data,
143 			  int data_len)
144 {
145 	u8 block_buffer[I2C_SMBUS_BLOCK_MAX];
146 	int result;
147 
148 	result = i2c_smbus_read_block_data(client, command, block_buffer);
149 	if (unlikely(result < 0))
150 		goto abort;
151 	if (unlikely(result == 0xff || result != data_len)) {
152 		result = -EIO;
153 		goto abort;
154 	}
155 	memcpy(data, block_buffer, data_len);
156 	result = 0;
157 abort:
158 	return result;
159 }
160 
161 static struct pem_data *pem_update_device(struct device *dev)
162 {
163 	struct i2c_client *client = to_i2c_client(dev);
164 	struct pem_data *data = i2c_get_clientdata(client);
165 	struct pem_data *ret = data;
166 
167 	mutex_lock(&data->update_lock);
168 
169 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
170 		int result;
171 
172 		/* Read data string */
173 		result = pem_read_block(client, PEM_READ_DATA_STRING,
174 					data->data_string,
175 					sizeof(data->data_string));
176 		if (unlikely(result < 0)) {
177 			ret = ERR_PTR(result);
178 			goto abort;
179 		}
180 
181 		/* Read input string */
182 		if (data->input_length) {
183 			result = pem_read_block(client, PEM_READ_INPUT_STRING,
184 						data->input_string,
185 						data->input_length);
186 			if (unlikely(result < 0)) {
187 				ret = ERR_PTR(result);
188 				goto abort;
189 			}
190 		}
191 
192 		/* Read fan speeds */
193 		if (data->fans_supported) {
194 			result = pem_read_block(client, PEM_READ_FAN_SPEED,
195 						data->fan_speed,
196 						sizeof(data->fan_speed));
197 			if (unlikely(result < 0)) {
198 				ret = ERR_PTR(result);
199 				goto abort;
200 			}
201 		}
202 
203 		i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
204 
205 		data->last_updated = jiffies;
206 		data->valid = 1;
207 	}
208 abort:
209 	mutex_unlock(&data->update_lock);
210 	return ret;
211 }
212 
213 static long pem_get_data(u8 *data, int len, int index)
214 {
215 	long val;
216 
217 	switch (index) {
218 	case PEM_DATA_VOUT_LSB:
219 		val = (data[index] + (data[index+1] << 8)) * 5 / 2;
220 		break;
221 	case PEM_DATA_CURRENT:
222 		val = data[index] * 200;
223 		break;
224 	case PEM_DATA_TEMP:
225 		val = data[index] * 1000;
226 		break;
227 	case PEM_DATA_TEMP_MAX:
228 		val = 97 * 1000;	/* 97 degrees C per datasheet */
229 		break;
230 	case PEM_DATA_TEMP_CRIT:
231 		val = 107 * 1000;	/* 107 degrees C per datasheet */
232 		break;
233 	default:
234 		WARN_ON_ONCE(1);
235 		val = 0;
236 	}
237 	return val;
238 }
239 
240 static long pem_get_input(u8 *data, int len, int index)
241 {
242 	long val;
243 
244 	switch (index) {
245 	case PEM_INPUT_VOLTAGE:
246 		if (len == INPUT_STRING_LEN)
247 			val = (data[index] + (data[index+1] << 8) - 75) * 1000;
248 		else
249 			val = (data[index] - 75) * 1000;
250 		break;
251 	case PEM_INPUT_POWER_LSB:
252 		if (len == INPUT_STRING_LEN)
253 			index++;
254 		val = (data[index] + (data[index+1] << 8)) * 1000000L;
255 		break;
256 	default:
257 		WARN_ON_ONCE(1);
258 		val = 0;
259 	}
260 	return val;
261 }
262 
263 static long pem_get_fan(u8 *data, int len, int index)
264 {
265 	long val;
266 
267 	switch (index) {
268 	case PEM_FAN_FAN1:
269 	case PEM_FAN_FAN2:
270 	case PEM_FAN_FAN3:
271 		val = data[index] * 100;
272 		break;
273 	default:
274 		WARN_ON_ONCE(1);
275 		val = 0;
276 	}
277 	return val;
278 }
279 
280 /*
281  * Show boolean, either a fault or an alarm.
282  * .nr points to the register, .index is the bit mask to check
283  */
284 static ssize_t pem_show_bool(struct device *dev,
285 			     struct device_attribute *da, char *buf)
286 {
287 	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
288 	struct pem_data *data = pem_update_device(dev);
289 	u8 status;
290 
291 	if (IS_ERR(data))
292 		return PTR_ERR(data);
293 
294 	status = data->data_string[attr->nr] & attr->index;
295 	return snprintf(buf, PAGE_SIZE, "%d\n", !!status);
296 }
297 
298 static ssize_t pem_show_data(struct device *dev, struct device_attribute *da,
299 			     char *buf)
300 {
301 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
302 	struct pem_data *data = pem_update_device(dev);
303 	long value;
304 
305 	if (IS_ERR(data))
306 		return PTR_ERR(data);
307 
308 	value = pem_get_data(data->data_string, sizeof(data->data_string),
309 			     attr->index);
310 
311 	return snprintf(buf, PAGE_SIZE, "%ld\n", value);
312 }
313 
314 static ssize_t pem_show_input(struct device *dev, struct device_attribute *da,
315 			      char *buf)
316 {
317 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
318 	struct pem_data *data = pem_update_device(dev);
319 	long value;
320 
321 	if (IS_ERR(data))
322 		return PTR_ERR(data);
323 
324 	value = pem_get_input(data->input_string, sizeof(data->input_string),
325 			      attr->index);
326 
327 	return snprintf(buf, PAGE_SIZE, "%ld\n", value);
328 }
329 
330 static ssize_t pem_show_fan(struct device *dev, struct device_attribute *da,
331 			    char *buf)
332 {
333 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
334 	struct pem_data *data = pem_update_device(dev);
335 	long value;
336 
337 	if (IS_ERR(data))
338 		return PTR_ERR(data);
339 
340 	value = pem_get_fan(data->fan_speed, sizeof(data->fan_speed),
341 			    attr->index);
342 
343 	return snprintf(buf, PAGE_SIZE, "%ld\n", value);
344 }
345 
346 /* Voltages */
347 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, pem_show_data, NULL,
348 			  PEM_DATA_VOUT_LSB);
349 static SENSOR_DEVICE_ATTR_2(in1_alarm, S_IRUGO, pem_show_bool, NULL,
350 			    PEM_DATA_ALARM_1, ALRM1_VOUT_OUT_LIMIT);
351 static SENSOR_DEVICE_ATTR_2(in1_crit_alarm, S_IRUGO, pem_show_bool, NULL,
352 			    PEM_DATA_ALARM_1, ALRM1_OV_VOLT_SHUTDOWN);
353 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, pem_show_input, NULL,
354 			  PEM_INPUT_VOLTAGE);
355 static SENSOR_DEVICE_ATTR_2(in2_alarm, S_IRUGO, pem_show_bool, NULL,
356 			    PEM_DATA_ALARM_1,
357 			    ALRM1_VIN_OUT_LIMIT | ALRM1_PRIMARY_FAULT);
358 
359 /* Currents */
360 static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, pem_show_data, NULL,
361 			  PEM_DATA_CURRENT);
362 static SENSOR_DEVICE_ATTR_2(curr1_alarm, S_IRUGO, pem_show_bool, NULL,
363 			    PEM_DATA_ALARM_1, ALRM1_VIN_OVERCURRENT);
364 
365 /* Power */
366 static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, pem_show_input, NULL,
367 			  PEM_INPUT_POWER_LSB);
368 static SENSOR_DEVICE_ATTR_2(power1_alarm, S_IRUGO, pem_show_bool, NULL,
369 			    PEM_DATA_ALARM_1, ALRM1_POWER_LIMIT);
370 
371 /* Fans */
372 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, pem_show_fan, NULL,
373 			  PEM_FAN_FAN1);
374 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, pem_show_fan, NULL,
375 			  PEM_FAN_FAN2);
376 static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, pem_show_fan, NULL,
377 			  PEM_FAN_FAN3);
378 static SENSOR_DEVICE_ATTR_2(fan1_alarm, S_IRUGO, pem_show_bool, NULL,
379 			    PEM_DATA_ALARM_2, ALRM2_FAN_FAULT);
380 
381 /* Temperatures */
382 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, pem_show_data, NULL,
383 			  PEM_DATA_TEMP);
384 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, pem_show_data, NULL,
385 			  PEM_DATA_TEMP_MAX);
386 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, pem_show_data, NULL,
387 			  PEM_DATA_TEMP_CRIT);
388 static SENSOR_DEVICE_ATTR_2(temp1_alarm, S_IRUGO, pem_show_bool, NULL,
389 			    PEM_DATA_ALARM_1, ALRM1_TEMP_WARNING);
390 static SENSOR_DEVICE_ATTR_2(temp1_crit_alarm, S_IRUGO, pem_show_bool, NULL,
391 			    PEM_DATA_ALARM_1, ALRM1_TEMP_SHUTDOWN);
392 static SENSOR_DEVICE_ATTR_2(temp1_fault, S_IRUGO, pem_show_bool, NULL,
393 			    PEM_DATA_ALARM_2, ALRM2_TEMP_FAULT);
394 
395 static struct attribute *pem_attributes[] = {
396 	&sensor_dev_attr_in1_input.dev_attr.attr,
397 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
398 	&sensor_dev_attr_in1_crit_alarm.dev_attr.attr,
399 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
400 
401 	&sensor_dev_attr_curr1_alarm.dev_attr.attr,
402 
403 	&sensor_dev_attr_power1_alarm.dev_attr.attr,
404 
405 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
406 
407 	&sensor_dev_attr_temp1_input.dev_attr.attr,
408 	&sensor_dev_attr_temp1_max.dev_attr.attr,
409 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
410 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
411 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
412 	&sensor_dev_attr_temp1_fault.dev_attr.attr,
413 
414 	NULL,
415 };
416 
417 static const struct attribute_group pem_group = {
418 	.attrs = pem_attributes,
419 };
420 
421 static struct attribute *pem_input_attributes[] = {
422 	&sensor_dev_attr_in2_input.dev_attr.attr,
423 	&sensor_dev_attr_curr1_input.dev_attr.attr,
424 	&sensor_dev_attr_power1_input.dev_attr.attr,
425 	NULL
426 };
427 
428 static const struct attribute_group pem_input_group = {
429 	.attrs = pem_input_attributes,
430 };
431 
432 static struct attribute *pem_fan_attributes[] = {
433 	&sensor_dev_attr_fan1_input.dev_attr.attr,
434 	&sensor_dev_attr_fan2_input.dev_attr.attr,
435 	&sensor_dev_attr_fan3_input.dev_attr.attr,
436 	NULL
437 };
438 
439 static const struct attribute_group pem_fan_group = {
440 	.attrs = pem_fan_attributes,
441 };
442 
443 static int pem_probe(struct i2c_client *client,
444 		     const struct i2c_device_id *id)
445 {
446 	struct i2c_adapter *adapter = client->adapter;
447 	struct pem_data *data;
448 	int ret;
449 
450 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BLOCK_DATA
451 				     | I2C_FUNC_SMBUS_WRITE_BYTE))
452 		return -ENODEV;
453 
454 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
455 	if (!data)
456 		return -ENOMEM;
457 
458 	i2c_set_clientdata(client, data);
459 	mutex_init(&data->update_lock);
460 
461 	/*
462 	 * We use the next two commands to determine if the device is really
463 	 * there.
464 	 */
465 	ret = pem_read_block(client, PEM_READ_FIRMWARE_REV,
466 			     data->firmware_rev, sizeof(data->firmware_rev));
467 	if (ret < 0)
468 		return ret;
469 
470 	ret = i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
471 	if (ret < 0)
472 		return ret;
473 
474 	dev_info(&client->dev, "Firmware revision %d.%d.%d\n",
475 		 data->firmware_rev[0], data->firmware_rev[1],
476 		 data->firmware_rev[2]);
477 
478 	/* Register sysfs hooks */
479 	ret = sysfs_create_group(&client->dev.kobj, &pem_group);
480 	if (ret)
481 		return ret;
482 
483 	/*
484 	 * Check if input readings are supported.
485 	 * This is the case if we can read input data,
486 	 * and if the returned data is not all zeros.
487 	 * Note that input alarms are always supported.
488 	 */
489 	ret = pem_read_block(client, PEM_READ_INPUT_STRING,
490 			     data->input_string,
491 			     sizeof(data->input_string) - 1);
492 	if (!ret && (data->input_string[0] || data->input_string[1] ||
493 		     data->input_string[2]))
494 		data->input_length = sizeof(data->input_string) - 1;
495 	else if (ret < 0) {
496 		/* Input string is one byte longer for some devices */
497 		ret = pem_read_block(client, PEM_READ_INPUT_STRING,
498 				    data->input_string,
499 				    sizeof(data->input_string));
500 		if (!ret && (data->input_string[0] || data->input_string[1] ||
501 			    data->input_string[2] || data->input_string[3]))
502 			data->input_length = sizeof(data->input_string);
503 	}
504 	ret = 0;
505 	if (data->input_length) {
506 		ret = sysfs_create_group(&client->dev.kobj, &pem_input_group);
507 		if (ret)
508 			goto out_remove_groups;
509 	}
510 
511 	/*
512 	 * Check if fan speed readings are supported.
513 	 * This is the case if we can read fan speed data,
514 	 * and if the returned data is not all zeros.
515 	 * Note that the fan alarm is always supported.
516 	 */
517 	ret = pem_read_block(client, PEM_READ_FAN_SPEED,
518 			     data->fan_speed,
519 			     sizeof(data->fan_speed));
520 	if (!ret && (data->fan_speed[0] || data->fan_speed[1] ||
521 		     data->fan_speed[2] || data->fan_speed[3])) {
522 		data->fans_supported = true;
523 		ret = sysfs_create_group(&client->dev.kobj, &pem_fan_group);
524 		if (ret)
525 			goto out_remove_groups;
526 	}
527 
528 	data->hwmon_dev = hwmon_device_register(&client->dev);
529 	if (IS_ERR(data->hwmon_dev)) {
530 		ret = PTR_ERR(data->hwmon_dev);
531 		goto out_remove_groups;
532 	}
533 
534 	return 0;
535 
536 out_remove_groups:
537 	sysfs_remove_group(&client->dev.kobj, &pem_input_group);
538 	sysfs_remove_group(&client->dev.kobj, &pem_fan_group);
539 	sysfs_remove_group(&client->dev.kobj, &pem_group);
540 	return ret;
541 }
542 
543 static int pem_remove(struct i2c_client *client)
544 {
545 	struct pem_data *data = i2c_get_clientdata(client);
546 
547 	hwmon_device_unregister(data->hwmon_dev);
548 
549 	sysfs_remove_group(&client->dev.kobj, &pem_input_group);
550 	sysfs_remove_group(&client->dev.kobj, &pem_fan_group);
551 	sysfs_remove_group(&client->dev.kobj, &pem_group);
552 
553 	return 0;
554 }
555 
556 static const struct i2c_device_id pem_id[] = {
557 	{"lineage_pem", 0},
558 	{}
559 };
560 MODULE_DEVICE_TABLE(i2c, pem_id);
561 
562 static struct i2c_driver pem_driver = {
563 	.driver = {
564 		   .name = "lineage_pem",
565 		   },
566 	.probe = pem_probe,
567 	.remove = pem_remove,
568 	.id_table = pem_id,
569 };
570 
571 module_i2c_driver(pem_driver);
572 
573 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
574 MODULE_DESCRIPTION("Lineage CPL PEM hardware monitoring driver");
575 MODULE_LICENSE("GPL");
576