1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Driver for Lineage Compact Power Line series of power entry modules.
4 *
5 * Copyright (C) 2010, 2011 Ericsson AB.
6 *
7 * Documentation:
8 *  http://www.lineagepower.com/oem/pdf/CPLI2C.pdf
9 */
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/err.h>
15#include <linux/slab.h>
16#include <linux/i2c.h>
17#include <linux/hwmon.h>
18#include <linux/hwmon-sysfs.h>
19#include <linux/jiffies.h>
20
21/*
22 * This driver supports various Lineage Compact Power Line DC/DC and AC/DC
23 * converters such as CP1800, CP2000AC, CP2000DC, CP2100DC, and others.
24 *
25 * The devices are nominally PMBus compliant. However, most standard PMBus
26 * commands are not supported. Specifically, all hardware monitoring and
27 * status reporting commands are non-standard. For this reason, a standard
28 * PMBus driver can not be used.
29 *
30 * All Lineage CPL devices have a built-in I2C bus master selector (PCA9541).
31 * To ensure device access, this driver should only be used as client driver
32 * to the pca9541 I2C master selector driver.
33 */
34
35/* Command codes */
36#define PEM_OPERATION		0x01
37#define PEM_CLEAR_INFO_FLAGS	0x03
38#define PEM_VOUT_COMMAND	0x21
39#define PEM_VOUT_OV_FAULT_LIMIT	0x40
40#define PEM_READ_DATA_STRING	0xd0
41#define PEM_READ_INPUT_STRING	0xdc
42#define PEM_READ_FIRMWARE_REV	0xdd
43#define PEM_READ_RUN_TIMER	0xde
44#define PEM_FAN_HI_SPEED	0xdf
45#define PEM_FAN_NORMAL_SPEED	0xe0
46#define PEM_READ_FAN_SPEED	0xe1
47
48/* offsets in data string */
49#define PEM_DATA_STATUS_2	0
50#define PEM_DATA_STATUS_1	1
51#define PEM_DATA_ALARM_2	2
52#define PEM_DATA_ALARM_1	3
53#define PEM_DATA_VOUT_LSB	4
54#define PEM_DATA_VOUT_MSB	5
55#define PEM_DATA_CURRENT	6
56#define PEM_DATA_TEMP		7
57
58/* Virtual entries, to report constants */
59#define PEM_DATA_TEMP_MAX	10
60#define PEM_DATA_TEMP_CRIT	11
61
62/* offsets in input string */
63#define PEM_INPUT_VOLTAGE	0
64#define PEM_INPUT_POWER_LSB	1
65#define PEM_INPUT_POWER_MSB	2
66
67/* offsets in fan data */
68#define PEM_FAN_ADJUSTMENT	0
69#define PEM_FAN_FAN1		1
70#define PEM_FAN_FAN2		2
71#define PEM_FAN_FAN3		3
72
73/* Status register bits */
74#define STS1_OUTPUT_ON		(1 << 0)
75#define STS1_LEDS_FLASHING	(1 << 1)
76#define STS1_EXT_FAULT		(1 << 2)
77#define STS1_SERVICE_LED_ON	(1 << 3)
78#define STS1_SHUTDOWN_OCCURRED	(1 << 4)
79#define STS1_INT_FAULT		(1 << 5)
80#define STS1_ISOLATION_TEST_OK	(1 << 6)
81
82#define STS2_ENABLE_PIN_HI	(1 << 0)
83#define STS2_DATA_OUT_RANGE	(1 << 1)
84#define STS2_RESTARTED_OK	(1 << 1)
85#define STS2_ISOLATION_TEST_FAIL (1 << 3)
86#define STS2_HIGH_POWER_CAP	(1 << 4)
87#define STS2_INVALID_INSTR	(1 << 5)
88#define STS2_WILL_RESTART	(1 << 6)
89#define STS2_PEC_ERR		(1 << 7)
90
91/* Alarm register bits */
92#define ALRM1_VIN_OUT_LIMIT	(1 << 0)
93#define ALRM1_VOUT_OUT_LIMIT	(1 << 1)
94#define ALRM1_OV_VOLT_SHUTDOWN	(1 << 2)
95#define ALRM1_VIN_OVERCURRENT	(1 << 3)
96#define ALRM1_TEMP_WARNING	(1 << 4)
97#define ALRM1_TEMP_SHUTDOWN	(1 << 5)
98#define ALRM1_PRIMARY_FAULT	(1 << 6)
99#define ALRM1_POWER_LIMIT	(1 << 7)
100
101#define ALRM2_5V_OUT_LIMIT	(1 << 1)
102#define ALRM2_TEMP_FAULT	(1 << 2)
103#define ALRM2_OV_LOW		(1 << 3)
104#define ALRM2_DCDC_TEMP_HIGH	(1 << 4)
105#define ALRM2_PRI_TEMP_HIGH	(1 << 5)
106#define ALRM2_NO_PRIMARY	(1 << 6)
107#define ALRM2_FAN_FAULT		(1 << 7)
108
109#define FIRMWARE_REV_LEN	4
110#define DATA_STRING_LEN		9
111#define INPUT_STRING_LEN	5	/* 4 for most devices	*/
112#define FAN_SPEED_LEN		5
113
114struct pem_data {
115	struct i2c_client *client;
116	const struct attribute_group *groups[4];
117
118	struct mutex update_lock;
119	bool valid;
120	bool fans_supported;
121	int input_length;
122	unsigned long last_updated;	/* in jiffies */
123
124	u8 firmware_rev[FIRMWARE_REV_LEN];
125	u8 data_string[DATA_STRING_LEN];
126	u8 input_string[INPUT_STRING_LEN];
127	u8 fan_speed[FAN_SPEED_LEN];
128};
129
130static int pem_read_block(struct i2c_client *client, u8 command, u8 *data,
131			  int data_len)
132{
133	u8 block_buffer[I2C_SMBUS_BLOCK_MAX];
134	int result;
135
136	result = i2c_smbus_read_block_data(client, command, block_buffer);
137	if (unlikely(result < 0))
138		goto abort;
139	if (unlikely(result == 0xff || result != data_len)) {
140		result = -EIO;
141		goto abort;
142	}
143	memcpy(data, block_buffer, data_len);
144	result = 0;
145abort:
146	return result;
147}
148
149static struct pem_data *pem_update_device(struct device *dev)
150{
151	struct pem_data *data = dev_get_drvdata(dev);
152	struct i2c_client *client = data->client;
153	struct pem_data *ret = data;
154
155	mutex_lock(&data->update_lock);
156
157	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
158		int result;
159
160		/* Read data string */
161		result = pem_read_block(client, PEM_READ_DATA_STRING,
162					data->data_string,
163					sizeof(data->data_string));
164		if (unlikely(result < 0)) {
165			ret = ERR_PTR(result);
166			goto abort;
167		}
168
169		/* Read input string */
170		if (data->input_length) {
171			result = pem_read_block(client, PEM_READ_INPUT_STRING,
172						data->input_string,
173						data->input_length);
174			if (unlikely(result < 0)) {
175				ret = ERR_PTR(result);
176				goto abort;
177			}
178		}
179
180		/* Read fan speeds */
181		if (data->fans_supported) {
182			result = pem_read_block(client, PEM_READ_FAN_SPEED,
183						data->fan_speed,
184						sizeof(data->fan_speed));
185			if (unlikely(result < 0)) {
186				ret = ERR_PTR(result);
187				goto abort;
188			}
189		}
190
191		i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
192
193		data->last_updated = jiffies;
194		data->valid = true;
195	}
196abort:
197	mutex_unlock(&data->update_lock);
198	return ret;
199}
200
201static long pem_get_data(u8 *data, int len, int index)
202{
203	long val;
204
205	switch (index) {
206	case PEM_DATA_VOUT_LSB:
207		val = (data[index] + (data[index+1] << 8)) * 5 / 2;
208		break;
209	case PEM_DATA_CURRENT:
210		val = data[index] * 200;
211		break;
212	case PEM_DATA_TEMP:
213		val = data[index] * 1000;
214		break;
215	case PEM_DATA_TEMP_MAX:
216		val = 97 * 1000;	/* 97 degrees C per datasheet */
217		break;
218	case PEM_DATA_TEMP_CRIT:
219		val = 107 * 1000;	/* 107 degrees C per datasheet */
220		break;
221	default:
222		WARN_ON_ONCE(1);
223		val = 0;
224	}
225	return val;
226}
227
228static long pem_get_input(u8 *data, int len, int index)
229{
230	long val;
231
232	switch (index) {
233	case PEM_INPUT_VOLTAGE:
234		if (len == INPUT_STRING_LEN)
235			val = (data[index] + (data[index+1] << 8) - 75) * 1000;
236		else
237			val = (data[index] - 75) * 1000;
238		break;
239	case PEM_INPUT_POWER_LSB:
240		if (len == INPUT_STRING_LEN)
241			index++;
242		val = (data[index] + (data[index+1] << 8)) * 1000000L;
243		break;
244	default:
245		WARN_ON_ONCE(1);
246		val = 0;
247	}
248	return val;
249}
250
251static long pem_get_fan(u8 *data, int len, int index)
252{
253	long val;
254
255	switch (index) {
256	case PEM_FAN_FAN1:
257	case PEM_FAN_FAN2:
258	case PEM_FAN_FAN3:
259		val = data[index] * 100;
260		break;
261	default:
262		WARN_ON_ONCE(1);
263		val = 0;
264	}
265	return val;
266}
267
268/*
269 * Show boolean, either a fault or an alarm.
270 * .nr points to the register, .index is the bit mask to check
271 */
272static ssize_t pem_bool_show(struct device *dev, struct device_attribute *da,
273			     char *buf)
274{
275	struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
276	struct pem_data *data = pem_update_device(dev);
277	u8 status;
278
279	if (IS_ERR(data))
280		return PTR_ERR(data);
281
282	status = data->data_string[attr->nr] & attr->index;
283	return sysfs_emit(buf, "%d\n", !!status);
284}
285
286static ssize_t pem_data_show(struct device *dev, struct device_attribute *da,
287			     char *buf)
288{
289	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
290	struct pem_data *data = pem_update_device(dev);
291	long value;
292
293	if (IS_ERR(data))
294		return PTR_ERR(data);
295
296	value = pem_get_data(data->data_string, sizeof(data->data_string),
297			     attr->index);
298
299	return sysfs_emit(buf, "%ld\n", value);
300}
301
302static ssize_t pem_input_show(struct device *dev, struct device_attribute *da,
303			      char *buf)
304{
305	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
306	struct pem_data *data = pem_update_device(dev);
307	long value;
308
309	if (IS_ERR(data))
310		return PTR_ERR(data);
311
312	value = pem_get_input(data->input_string, sizeof(data->input_string),
313			      attr->index);
314
315	return sysfs_emit(buf, "%ld\n", value);
316}
317
318static ssize_t pem_fan_show(struct device *dev, struct device_attribute *da,
319			    char *buf)
320{
321	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
322	struct pem_data *data = pem_update_device(dev);
323	long value;
324
325	if (IS_ERR(data))
326		return PTR_ERR(data);
327
328	value = pem_get_fan(data->fan_speed, sizeof(data->fan_speed),
329			    attr->index);
330
331	return sysfs_emit(buf, "%ld\n", value);
332}
333
334/* Voltages */
335static SENSOR_DEVICE_ATTR_RO(in1_input, pem_data, PEM_DATA_VOUT_LSB);
336static SENSOR_DEVICE_ATTR_2_RO(in1_alarm, pem_bool, PEM_DATA_ALARM_1,
337			       ALRM1_VOUT_OUT_LIMIT);
338static SENSOR_DEVICE_ATTR_2_RO(in1_crit_alarm, pem_bool, PEM_DATA_ALARM_1,
339			       ALRM1_OV_VOLT_SHUTDOWN);
340static SENSOR_DEVICE_ATTR_RO(in2_input, pem_input, PEM_INPUT_VOLTAGE);
341static SENSOR_DEVICE_ATTR_2_RO(in2_alarm, pem_bool, PEM_DATA_ALARM_1,
342			       ALRM1_VIN_OUT_LIMIT | ALRM1_PRIMARY_FAULT);
343
344/* Currents */
345static SENSOR_DEVICE_ATTR_RO(curr1_input, pem_data, PEM_DATA_CURRENT);
346static SENSOR_DEVICE_ATTR_2_RO(curr1_alarm, pem_bool, PEM_DATA_ALARM_1,
347			       ALRM1_VIN_OVERCURRENT);
348
349/* Power */
350static SENSOR_DEVICE_ATTR_RO(power1_input, pem_input, PEM_INPUT_POWER_LSB);
351static SENSOR_DEVICE_ATTR_2_RO(power1_alarm, pem_bool, PEM_DATA_ALARM_1,
352			       ALRM1_POWER_LIMIT);
353
354/* Fans */
355static SENSOR_DEVICE_ATTR_RO(fan1_input, pem_fan, PEM_FAN_FAN1);
356static SENSOR_DEVICE_ATTR_RO(fan2_input, pem_fan, PEM_FAN_FAN2);
357static SENSOR_DEVICE_ATTR_RO(fan3_input, pem_fan, PEM_FAN_FAN3);
358static SENSOR_DEVICE_ATTR_2_RO(fan1_alarm, pem_bool, PEM_DATA_ALARM_2,
359			       ALRM2_FAN_FAULT);
360
361/* Temperatures */
362static SENSOR_DEVICE_ATTR_RO(temp1_input, pem_data, PEM_DATA_TEMP);
363static SENSOR_DEVICE_ATTR_RO(temp1_max, pem_data, PEM_DATA_TEMP_MAX);
364static SENSOR_DEVICE_ATTR_RO(temp1_crit, pem_data, PEM_DATA_TEMP_CRIT);
365static SENSOR_DEVICE_ATTR_2_RO(temp1_alarm, pem_bool, PEM_DATA_ALARM_1,
366			       ALRM1_TEMP_WARNING);
367static SENSOR_DEVICE_ATTR_2_RO(temp1_crit_alarm, pem_bool, PEM_DATA_ALARM_1,
368			       ALRM1_TEMP_SHUTDOWN);
369static SENSOR_DEVICE_ATTR_2_RO(temp1_fault, pem_bool, PEM_DATA_ALARM_2,
370			       ALRM2_TEMP_FAULT);
371
372static struct attribute *pem_attributes[] = {
373	&sensor_dev_attr_in1_input.dev_attr.attr,
374	&sensor_dev_attr_in1_alarm.dev_attr.attr,
375	&sensor_dev_attr_in1_crit_alarm.dev_attr.attr,
376	&sensor_dev_attr_in2_alarm.dev_attr.attr,
377
378	&sensor_dev_attr_curr1_alarm.dev_attr.attr,
379
380	&sensor_dev_attr_power1_alarm.dev_attr.attr,
381
382	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
383
384	&sensor_dev_attr_temp1_input.dev_attr.attr,
385	&sensor_dev_attr_temp1_max.dev_attr.attr,
386	&sensor_dev_attr_temp1_crit.dev_attr.attr,
387	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
388	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
389	&sensor_dev_attr_temp1_fault.dev_attr.attr,
390
391	NULL,
392};
393
394static const struct attribute_group pem_group = {
395	.attrs = pem_attributes,
396};
397
398static struct attribute *pem_input_attributes[] = {
399	&sensor_dev_attr_in2_input.dev_attr.attr,
400	&sensor_dev_attr_curr1_input.dev_attr.attr,
401	&sensor_dev_attr_power1_input.dev_attr.attr,
402	NULL
403};
404
405static const struct attribute_group pem_input_group = {
406	.attrs = pem_input_attributes,
407};
408
409static struct attribute *pem_fan_attributes[] = {
410	&sensor_dev_attr_fan1_input.dev_attr.attr,
411	&sensor_dev_attr_fan2_input.dev_attr.attr,
412	&sensor_dev_attr_fan3_input.dev_attr.attr,
413	NULL
414};
415
416static const struct attribute_group pem_fan_group = {
417	.attrs = pem_fan_attributes,
418};
419
420static int pem_probe(struct i2c_client *client)
421{
422	struct i2c_adapter *adapter = client->adapter;
423	struct device *dev = &client->dev;
424	struct device *hwmon_dev;
425	struct pem_data *data;
426	int ret, idx = 0;
427
428	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BLOCK_DATA
429				     | I2C_FUNC_SMBUS_WRITE_BYTE))
430		return -ENODEV;
431
432	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
433	if (!data)
434		return -ENOMEM;
435
436	data->client = client;
437	mutex_init(&data->update_lock);
438
439	/*
440	 * We use the next two commands to determine if the device is really
441	 * there.
442	 */
443	ret = pem_read_block(client, PEM_READ_FIRMWARE_REV,
444			     data->firmware_rev, sizeof(data->firmware_rev));
445	if (ret < 0)
446		return ret;
447
448	ret = i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
449	if (ret < 0)
450		return ret;
451
452	dev_info(dev, "Firmware revision %d.%d.%d\n",
453		 data->firmware_rev[0], data->firmware_rev[1],
454		 data->firmware_rev[2]);
455
456	/* sysfs hooks */
457	data->groups[idx++] = &pem_group;
458
459	/*
460	 * Check if input readings are supported.
461	 * This is the case if we can read input data,
462	 * and if the returned data is not all zeros.
463	 * Note that input alarms are always supported.
464	 */
465	ret = pem_read_block(client, PEM_READ_INPUT_STRING,
466			     data->input_string,
467			     sizeof(data->input_string) - 1);
468	if (!ret && (data->input_string[0] || data->input_string[1] ||
469		     data->input_string[2]))
470		data->input_length = sizeof(data->input_string) - 1;
471	else if (ret < 0) {
472		/* Input string is one byte longer for some devices */
473		ret = pem_read_block(client, PEM_READ_INPUT_STRING,
474				    data->input_string,
475				    sizeof(data->input_string));
476		if (!ret && (data->input_string[0] || data->input_string[1] ||
477			    data->input_string[2] || data->input_string[3]))
478			data->input_length = sizeof(data->input_string);
479	}
480
481	if (data->input_length)
482		data->groups[idx++] = &pem_input_group;
483
484	/*
485	 * Check if fan speed readings are supported.
486	 * This is the case if we can read fan speed data,
487	 * and if the returned data is not all zeros.
488	 * Note that the fan alarm is always supported.
489	 */
490	ret = pem_read_block(client, PEM_READ_FAN_SPEED,
491			     data->fan_speed,
492			     sizeof(data->fan_speed));
493	if (!ret && (data->fan_speed[0] || data->fan_speed[1] ||
494		     data->fan_speed[2] || data->fan_speed[3])) {
495		data->fans_supported = true;
496		data->groups[idx++] = &pem_fan_group;
497	}
498
499	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
500							   data, data->groups);
501	return PTR_ERR_OR_ZERO(hwmon_dev);
502}
503
504static const struct i2c_device_id pem_id[] = {
505	{"lineage_pem"},
506	{}
507};
508MODULE_DEVICE_TABLE(i2c, pem_id);
509
510static struct i2c_driver pem_driver = {
511	.driver = {
512		   .name = "lineage_pem",
513		   },
514	.probe = pem_probe,
515	.id_table = pem_id,
516};
517
518module_i2c_driver(pem_driver);
519
520MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
521MODULE_DESCRIPTION("Lineage CPL PEM hardware monitoring driver");
522MODULE_LICENSE("GPL");
523