xref: /openbmc/linux/drivers/hwmon/lineage-pem.c (revision be709d48)
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 i2c_client *client;
129 	const struct attribute_group *groups[4];
130 
131 	struct mutex update_lock;
132 	bool valid;
133 	bool fans_supported;
134 	int input_length;
135 	unsigned long last_updated;	/* in jiffies */
136 
137 	u8 firmware_rev[FIRMWARE_REV_LEN];
138 	u8 data_string[DATA_STRING_LEN];
139 	u8 input_string[INPUT_STRING_LEN];
140 	u8 fan_speed[FAN_SPEED_LEN];
141 };
142 
143 static int pem_read_block(struct i2c_client *client, u8 command, u8 *data,
144 			  int data_len)
145 {
146 	u8 block_buffer[I2C_SMBUS_BLOCK_MAX];
147 	int result;
148 
149 	result = i2c_smbus_read_block_data(client, command, block_buffer);
150 	if (unlikely(result < 0))
151 		goto abort;
152 	if (unlikely(result == 0xff || result != data_len)) {
153 		result = -EIO;
154 		goto abort;
155 	}
156 	memcpy(data, block_buffer, data_len);
157 	result = 0;
158 abort:
159 	return result;
160 }
161 
162 static struct pem_data *pem_update_device(struct device *dev)
163 {
164 	struct pem_data *data = dev_get_drvdata(dev);
165 	struct i2c_client *client = data->client;
166 	struct pem_data *ret = data;
167 
168 	mutex_lock(&data->update_lock);
169 
170 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
171 		int result;
172 
173 		/* Read data string */
174 		result = pem_read_block(client, PEM_READ_DATA_STRING,
175 					data->data_string,
176 					sizeof(data->data_string));
177 		if (unlikely(result < 0)) {
178 			ret = ERR_PTR(result);
179 			goto abort;
180 		}
181 
182 		/* Read input string */
183 		if (data->input_length) {
184 			result = pem_read_block(client, PEM_READ_INPUT_STRING,
185 						data->input_string,
186 						data->input_length);
187 			if (unlikely(result < 0)) {
188 				ret = ERR_PTR(result);
189 				goto abort;
190 			}
191 		}
192 
193 		/* Read fan speeds */
194 		if (data->fans_supported) {
195 			result = pem_read_block(client, PEM_READ_FAN_SPEED,
196 						data->fan_speed,
197 						sizeof(data->fan_speed));
198 			if (unlikely(result < 0)) {
199 				ret = ERR_PTR(result);
200 				goto abort;
201 			}
202 		}
203 
204 		i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
205 
206 		data->last_updated = jiffies;
207 		data->valid = 1;
208 	}
209 abort:
210 	mutex_unlock(&data->update_lock);
211 	return ret;
212 }
213 
214 static long pem_get_data(u8 *data, int len, int index)
215 {
216 	long val;
217 
218 	switch (index) {
219 	case PEM_DATA_VOUT_LSB:
220 		val = (data[index] + (data[index+1] << 8)) * 5 / 2;
221 		break;
222 	case PEM_DATA_CURRENT:
223 		val = data[index] * 200;
224 		break;
225 	case PEM_DATA_TEMP:
226 		val = data[index] * 1000;
227 		break;
228 	case PEM_DATA_TEMP_MAX:
229 		val = 97 * 1000;	/* 97 degrees C per datasheet */
230 		break;
231 	case PEM_DATA_TEMP_CRIT:
232 		val = 107 * 1000;	/* 107 degrees C per datasheet */
233 		break;
234 	default:
235 		WARN_ON_ONCE(1);
236 		val = 0;
237 	}
238 	return val;
239 }
240 
241 static long pem_get_input(u8 *data, int len, int index)
242 {
243 	long val;
244 
245 	switch (index) {
246 	case PEM_INPUT_VOLTAGE:
247 		if (len == INPUT_STRING_LEN)
248 			val = (data[index] + (data[index+1] << 8) - 75) * 1000;
249 		else
250 			val = (data[index] - 75) * 1000;
251 		break;
252 	case PEM_INPUT_POWER_LSB:
253 		if (len == INPUT_STRING_LEN)
254 			index++;
255 		val = (data[index] + (data[index+1] << 8)) * 1000000L;
256 		break;
257 	default:
258 		WARN_ON_ONCE(1);
259 		val = 0;
260 	}
261 	return val;
262 }
263 
264 static long pem_get_fan(u8 *data, int len, int index)
265 {
266 	long val;
267 
268 	switch (index) {
269 	case PEM_FAN_FAN1:
270 	case PEM_FAN_FAN2:
271 	case PEM_FAN_FAN3:
272 		val = data[index] * 100;
273 		break;
274 	default:
275 		WARN_ON_ONCE(1);
276 		val = 0;
277 	}
278 	return val;
279 }
280 
281 /*
282  * Show boolean, either a fault or an alarm.
283  * .nr points to the register, .index is the bit mask to check
284  */
285 static ssize_t pem_bool_show(struct device *dev, struct device_attribute *da,
286 			     char *buf)
287 {
288 	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
289 	struct pem_data *data = pem_update_device(dev);
290 	u8 status;
291 
292 	if (IS_ERR(data))
293 		return PTR_ERR(data);
294 
295 	status = data->data_string[attr->nr] & attr->index;
296 	return snprintf(buf, PAGE_SIZE, "%d\n", !!status);
297 }
298 
299 static ssize_t pem_data_show(struct device *dev, struct device_attribute *da,
300 			     char *buf)
301 {
302 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
303 	struct pem_data *data = pem_update_device(dev);
304 	long value;
305 
306 	if (IS_ERR(data))
307 		return PTR_ERR(data);
308 
309 	value = pem_get_data(data->data_string, sizeof(data->data_string),
310 			     attr->index);
311 
312 	return snprintf(buf, PAGE_SIZE, "%ld\n", value);
313 }
314 
315 static ssize_t pem_input_show(struct device *dev, struct device_attribute *da,
316 			      char *buf)
317 {
318 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
319 	struct pem_data *data = pem_update_device(dev);
320 	long value;
321 
322 	if (IS_ERR(data))
323 		return PTR_ERR(data);
324 
325 	value = pem_get_input(data->input_string, sizeof(data->input_string),
326 			      attr->index);
327 
328 	return snprintf(buf, PAGE_SIZE, "%ld\n", value);
329 }
330 
331 static ssize_t pem_fan_show(struct device *dev, struct device_attribute *da,
332 			    char *buf)
333 {
334 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
335 	struct pem_data *data = pem_update_device(dev);
336 	long value;
337 
338 	if (IS_ERR(data))
339 		return PTR_ERR(data);
340 
341 	value = pem_get_fan(data->fan_speed, sizeof(data->fan_speed),
342 			    attr->index);
343 
344 	return snprintf(buf, PAGE_SIZE, "%ld\n", value);
345 }
346 
347 /* Voltages */
348 static SENSOR_DEVICE_ATTR_RO(in1_input, pem_data, PEM_DATA_VOUT_LSB);
349 static SENSOR_DEVICE_ATTR_2_RO(in1_alarm, pem_bool, PEM_DATA_ALARM_1,
350 			       ALRM1_VOUT_OUT_LIMIT);
351 static SENSOR_DEVICE_ATTR_2_RO(in1_crit_alarm, pem_bool, PEM_DATA_ALARM_1,
352 			       ALRM1_OV_VOLT_SHUTDOWN);
353 static SENSOR_DEVICE_ATTR_RO(in2_input, pem_input, PEM_INPUT_VOLTAGE);
354 static SENSOR_DEVICE_ATTR_2_RO(in2_alarm, pem_bool, PEM_DATA_ALARM_1,
355 			       ALRM1_VIN_OUT_LIMIT | ALRM1_PRIMARY_FAULT);
356 
357 /* Currents */
358 static SENSOR_DEVICE_ATTR_RO(curr1_input, pem_data, PEM_DATA_CURRENT);
359 static SENSOR_DEVICE_ATTR_2_RO(curr1_alarm, pem_bool, PEM_DATA_ALARM_1,
360 			       ALRM1_VIN_OVERCURRENT);
361 
362 /* Power */
363 static SENSOR_DEVICE_ATTR_RO(power1_input, pem_input, PEM_INPUT_POWER_LSB);
364 static SENSOR_DEVICE_ATTR_2_RO(power1_alarm, pem_bool, PEM_DATA_ALARM_1,
365 			       ALRM1_POWER_LIMIT);
366 
367 /* Fans */
368 static SENSOR_DEVICE_ATTR_RO(fan1_input, pem_fan, PEM_FAN_FAN1);
369 static SENSOR_DEVICE_ATTR_RO(fan2_input, pem_fan, PEM_FAN_FAN2);
370 static SENSOR_DEVICE_ATTR_RO(fan3_input, pem_fan, PEM_FAN_FAN3);
371 static SENSOR_DEVICE_ATTR_2_RO(fan1_alarm, pem_bool, PEM_DATA_ALARM_2,
372 			       ALRM2_FAN_FAULT);
373 
374 /* Temperatures */
375 static SENSOR_DEVICE_ATTR_RO(temp1_input, pem_data, PEM_DATA_TEMP);
376 static SENSOR_DEVICE_ATTR_RO(temp1_max, pem_data, PEM_DATA_TEMP_MAX);
377 static SENSOR_DEVICE_ATTR_RO(temp1_crit, pem_data, PEM_DATA_TEMP_CRIT);
378 static SENSOR_DEVICE_ATTR_2_RO(temp1_alarm, pem_bool, PEM_DATA_ALARM_1,
379 			       ALRM1_TEMP_WARNING);
380 static SENSOR_DEVICE_ATTR_2_RO(temp1_crit_alarm, pem_bool, PEM_DATA_ALARM_1,
381 			       ALRM1_TEMP_SHUTDOWN);
382 static SENSOR_DEVICE_ATTR_2_RO(temp1_fault, pem_bool, PEM_DATA_ALARM_2,
383 			       ALRM2_TEMP_FAULT);
384 
385 static struct attribute *pem_attributes[] = {
386 	&sensor_dev_attr_in1_input.dev_attr.attr,
387 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
388 	&sensor_dev_attr_in1_crit_alarm.dev_attr.attr,
389 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
390 
391 	&sensor_dev_attr_curr1_alarm.dev_attr.attr,
392 
393 	&sensor_dev_attr_power1_alarm.dev_attr.attr,
394 
395 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
396 
397 	&sensor_dev_attr_temp1_input.dev_attr.attr,
398 	&sensor_dev_attr_temp1_max.dev_attr.attr,
399 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
400 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
401 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
402 	&sensor_dev_attr_temp1_fault.dev_attr.attr,
403 
404 	NULL,
405 };
406 
407 static const struct attribute_group pem_group = {
408 	.attrs = pem_attributes,
409 };
410 
411 static struct attribute *pem_input_attributes[] = {
412 	&sensor_dev_attr_in2_input.dev_attr.attr,
413 	&sensor_dev_attr_curr1_input.dev_attr.attr,
414 	&sensor_dev_attr_power1_input.dev_attr.attr,
415 	NULL
416 };
417 
418 static const struct attribute_group pem_input_group = {
419 	.attrs = pem_input_attributes,
420 };
421 
422 static struct attribute *pem_fan_attributes[] = {
423 	&sensor_dev_attr_fan1_input.dev_attr.attr,
424 	&sensor_dev_attr_fan2_input.dev_attr.attr,
425 	&sensor_dev_attr_fan3_input.dev_attr.attr,
426 	NULL
427 };
428 
429 static const struct attribute_group pem_fan_group = {
430 	.attrs = pem_fan_attributes,
431 };
432 
433 static int pem_probe(struct i2c_client *client,
434 		     const struct i2c_device_id *id)
435 {
436 	struct i2c_adapter *adapter = client->adapter;
437 	struct device *dev = &client->dev;
438 	struct device *hwmon_dev;
439 	struct pem_data *data;
440 	int ret, idx = 0;
441 
442 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BLOCK_DATA
443 				     | I2C_FUNC_SMBUS_WRITE_BYTE))
444 		return -ENODEV;
445 
446 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
447 	if (!data)
448 		return -ENOMEM;
449 
450 	data->client = client;
451 	mutex_init(&data->update_lock);
452 
453 	/*
454 	 * We use the next two commands to determine if the device is really
455 	 * there.
456 	 */
457 	ret = pem_read_block(client, PEM_READ_FIRMWARE_REV,
458 			     data->firmware_rev, sizeof(data->firmware_rev));
459 	if (ret < 0)
460 		return ret;
461 
462 	ret = i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
463 	if (ret < 0)
464 		return ret;
465 
466 	dev_info(dev, "Firmware revision %d.%d.%d\n",
467 		 data->firmware_rev[0], data->firmware_rev[1],
468 		 data->firmware_rev[2]);
469 
470 	/* sysfs hooks */
471 	data->groups[idx++] = &pem_group;
472 
473 	/*
474 	 * Check if input readings are supported.
475 	 * This is the case if we can read input data,
476 	 * and if the returned data is not all zeros.
477 	 * Note that input alarms are always supported.
478 	 */
479 	ret = pem_read_block(client, PEM_READ_INPUT_STRING,
480 			     data->input_string,
481 			     sizeof(data->input_string) - 1);
482 	if (!ret && (data->input_string[0] || data->input_string[1] ||
483 		     data->input_string[2]))
484 		data->input_length = sizeof(data->input_string) - 1;
485 	else if (ret < 0) {
486 		/* Input string is one byte longer for some devices */
487 		ret = pem_read_block(client, PEM_READ_INPUT_STRING,
488 				    data->input_string,
489 				    sizeof(data->input_string));
490 		if (!ret && (data->input_string[0] || data->input_string[1] ||
491 			    data->input_string[2] || data->input_string[3]))
492 			data->input_length = sizeof(data->input_string);
493 	}
494 
495 	if (data->input_length)
496 		data->groups[idx++] = &pem_input_group;
497 
498 	/*
499 	 * Check if fan speed readings are supported.
500 	 * This is the case if we can read fan speed data,
501 	 * and if the returned data is not all zeros.
502 	 * Note that the fan alarm is always supported.
503 	 */
504 	ret = pem_read_block(client, PEM_READ_FAN_SPEED,
505 			     data->fan_speed,
506 			     sizeof(data->fan_speed));
507 	if (!ret && (data->fan_speed[0] || data->fan_speed[1] ||
508 		     data->fan_speed[2] || data->fan_speed[3])) {
509 		data->fans_supported = true;
510 		data->groups[idx++] = &pem_fan_group;
511 	}
512 
513 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
514 							   data, data->groups);
515 	return PTR_ERR_OR_ZERO(hwmon_dev);
516 }
517 
518 static const struct i2c_device_id pem_id[] = {
519 	{"lineage_pem", 0},
520 	{}
521 };
522 MODULE_DEVICE_TABLE(i2c, pem_id);
523 
524 static struct i2c_driver pem_driver = {
525 	.driver = {
526 		   .name = "lineage_pem",
527 		   },
528 	.probe = pem_probe,
529 	.id_table = pem_id,
530 };
531 
532 module_i2c_driver(pem_driver);
533 
534 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
535 MODULE_DESCRIPTION("Lineage CPL PEM hardware monitoring driver");
536 MODULE_LICENSE("GPL");
537