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
127struct 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
143static 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;
158abort:
159	return result;
160}
161
162static 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	}
209abort:
210	mutex_unlock(&data->update_lock);
211	return ret;
212}
213
214static 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
241static 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
264static 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 */
285static ssize_t pem_show_bool(struct device *dev,
286			     struct device_attribute *da, 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
299static ssize_t pem_show_data(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
315static ssize_t pem_show_input(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
331static ssize_t pem_show_fan(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 */
348static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, pem_show_data, NULL,
349			  PEM_DATA_VOUT_LSB);
350static SENSOR_DEVICE_ATTR_2(in1_alarm, S_IRUGO, pem_show_bool, NULL,
351			    PEM_DATA_ALARM_1, ALRM1_VOUT_OUT_LIMIT);
352static SENSOR_DEVICE_ATTR_2(in1_crit_alarm, S_IRUGO, pem_show_bool, NULL,
353			    PEM_DATA_ALARM_1, ALRM1_OV_VOLT_SHUTDOWN);
354static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, pem_show_input, NULL,
355			  PEM_INPUT_VOLTAGE);
356static SENSOR_DEVICE_ATTR_2(in2_alarm, S_IRUGO, pem_show_bool, NULL,
357			    PEM_DATA_ALARM_1,
358			    ALRM1_VIN_OUT_LIMIT | ALRM1_PRIMARY_FAULT);
359
360/* Currents */
361static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, pem_show_data, NULL,
362			  PEM_DATA_CURRENT);
363static SENSOR_DEVICE_ATTR_2(curr1_alarm, S_IRUGO, pem_show_bool, NULL,
364			    PEM_DATA_ALARM_1, ALRM1_VIN_OVERCURRENT);
365
366/* Power */
367static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, pem_show_input, NULL,
368			  PEM_INPUT_POWER_LSB);
369static SENSOR_DEVICE_ATTR_2(power1_alarm, S_IRUGO, pem_show_bool, NULL,
370			    PEM_DATA_ALARM_1, ALRM1_POWER_LIMIT);
371
372/* Fans */
373static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, pem_show_fan, NULL,
374			  PEM_FAN_FAN1);
375static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, pem_show_fan, NULL,
376			  PEM_FAN_FAN2);
377static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, pem_show_fan, NULL,
378			  PEM_FAN_FAN3);
379static SENSOR_DEVICE_ATTR_2(fan1_alarm, S_IRUGO, pem_show_bool, NULL,
380			    PEM_DATA_ALARM_2, ALRM2_FAN_FAULT);
381
382/* Temperatures */
383static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, pem_show_data, NULL,
384			  PEM_DATA_TEMP);
385static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, pem_show_data, NULL,
386			  PEM_DATA_TEMP_MAX);
387static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, pem_show_data, NULL,
388			  PEM_DATA_TEMP_CRIT);
389static SENSOR_DEVICE_ATTR_2(temp1_alarm, S_IRUGO, pem_show_bool, NULL,
390			    PEM_DATA_ALARM_1, ALRM1_TEMP_WARNING);
391static SENSOR_DEVICE_ATTR_2(temp1_crit_alarm, S_IRUGO, pem_show_bool, NULL,
392			    PEM_DATA_ALARM_1, ALRM1_TEMP_SHUTDOWN);
393static SENSOR_DEVICE_ATTR_2(temp1_fault, S_IRUGO, pem_show_bool, NULL,
394			    PEM_DATA_ALARM_2, ALRM2_TEMP_FAULT);
395
396static struct attribute *pem_attributes[] = {
397	&sensor_dev_attr_in1_input.dev_attr.attr,
398	&sensor_dev_attr_in1_alarm.dev_attr.attr,
399	&sensor_dev_attr_in1_crit_alarm.dev_attr.attr,
400	&sensor_dev_attr_in2_alarm.dev_attr.attr,
401
402	&sensor_dev_attr_curr1_alarm.dev_attr.attr,
403
404	&sensor_dev_attr_power1_alarm.dev_attr.attr,
405
406	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
407
408	&sensor_dev_attr_temp1_input.dev_attr.attr,
409	&sensor_dev_attr_temp1_max.dev_attr.attr,
410	&sensor_dev_attr_temp1_crit.dev_attr.attr,
411	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
412	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
413	&sensor_dev_attr_temp1_fault.dev_attr.attr,
414
415	NULL,
416};
417
418static const struct attribute_group pem_group = {
419	.attrs = pem_attributes,
420};
421
422static struct attribute *pem_input_attributes[] = {
423	&sensor_dev_attr_in2_input.dev_attr.attr,
424	&sensor_dev_attr_curr1_input.dev_attr.attr,
425	&sensor_dev_attr_power1_input.dev_attr.attr,
426	NULL
427};
428
429static const struct attribute_group pem_input_group = {
430	.attrs = pem_input_attributes,
431};
432
433static struct attribute *pem_fan_attributes[] = {
434	&sensor_dev_attr_fan1_input.dev_attr.attr,
435	&sensor_dev_attr_fan2_input.dev_attr.attr,
436	&sensor_dev_attr_fan3_input.dev_attr.attr,
437	NULL
438};
439
440static const struct attribute_group pem_fan_group = {
441	.attrs = pem_fan_attributes,
442};
443
444static int pem_probe(struct i2c_client *client,
445		     const struct i2c_device_id *id)
446{
447	struct i2c_adapter *adapter = client->adapter;
448	struct device *dev = &client->dev;
449	struct device *hwmon_dev;
450	struct pem_data *data;
451	int ret, idx = 0;
452
453	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BLOCK_DATA
454				     | I2C_FUNC_SMBUS_WRITE_BYTE))
455		return -ENODEV;
456
457	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
458	if (!data)
459		return -ENOMEM;
460
461	data->client = client;
462	mutex_init(&data->update_lock);
463
464	/*
465	 * We use the next two commands to determine if the device is really
466	 * there.
467	 */
468	ret = pem_read_block(client, PEM_READ_FIRMWARE_REV,
469			     data->firmware_rev, sizeof(data->firmware_rev));
470	if (ret < 0)
471		return ret;
472
473	ret = i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
474	if (ret < 0)
475		return ret;
476
477	dev_info(dev, "Firmware revision %d.%d.%d\n",
478		 data->firmware_rev[0], data->firmware_rev[1],
479		 data->firmware_rev[2]);
480
481	/* sysfs hooks */
482	data->groups[idx++] = &pem_group;
483
484	/*
485	 * Check if input readings are supported.
486	 * This is the case if we can read input data,
487	 * and if the returned data is not all zeros.
488	 * Note that input alarms are always supported.
489	 */
490	ret = pem_read_block(client, PEM_READ_INPUT_STRING,
491			     data->input_string,
492			     sizeof(data->input_string) - 1);
493	if (!ret && (data->input_string[0] || data->input_string[1] ||
494		     data->input_string[2]))
495		data->input_length = sizeof(data->input_string) - 1;
496	else if (ret < 0) {
497		/* Input string is one byte longer for some devices */
498		ret = pem_read_block(client, PEM_READ_INPUT_STRING,
499				    data->input_string,
500				    sizeof(data->input_string));
501		if (!ret && (data->input_string[0] || data->input_string[1] ||
502			    data->input_string[2] || data->input_string[3]))
503			data->input_length = sizeof(data->input_string);
504	}
505
506	if (data->input_length)
507		data->groups[idx++] = &pem_input_group;
508
509	/*
510	 * Check if fan speed readings are supported.
511	 * This is the case if we can read fan speed data,
512	 * and if the returned data is not all zeros.
513	 * Note that the fan alarm is always supported.
514	 */
515	ret = pem_read_block(client, PEM_READ_FAN_SPEED,
516			     data->fan_speed,
517			     sizeof(data->fan_speed));
518	if (!ret && (data->fan_speed[0] || data->fan_speed[1] ||
519		     data->fan_speed[2] || data->fan_speed[3])) {
520		data->fans_supported = true;
521		data->groups[idx++] = &pem_fan_group;
522	}
523
524	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
525							   data, data->groups);
526	return PTR_ERR_OR_ZERO(hwmon_dev);
527}
528
529static const struct i2c_device_id pem_id[] = {
530	{"lineage_pem", 0},
531	{}
532};
533MODULE_DEVICE_TABLE(i2c, pem_id);
534
535static struct i2c_driver pem_driver = {
536	.driver = {
537		   .name = "lineage_pem",
538		   },
539	.probe = pem_probe,
540	.id_table = pem_id,
541};
542
543module_i2c_driver(pem_driver);
544
545MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
546MODULE_DESCRIPTION("Lineage CPL PEM hardware monitoring driver");
547MODULE_LICENSE("GPL");
548