• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1Kernel driver pmbus
2====================
3
4Supported chips:
5  * Ericsson BMR453, BMR454
6    Prefixes: 'bmr453', 'bmr454'
7    Addresses scanned: -
8    Datasheet:
9 http://archive.ericsson.net/service/internet/picov/get?DocNo=28701-EN/LZT146395
10  * ON Semiconductor ADP4000, NCP4200, NCP4208
11    Prefixes: 'adp4000', 'ncp4200', 'ncp4208'
12    Addresses scanned: -
13    Datasheets:
14	http://www.onsemi.com/pub_link/Collateral/ADP4000-D.PDF
15	http://www.onsemi.com/pub_link/Collateral/NCP4200-D.PDF
16	http://www.onsemi.com/pub_link/Collateral/JUNE%202009-%20REV.%200.PDF
17  * Lineage Power
18    Prefixes: 'mdt040', 'pdt003', 'pdt006', 'pdt012', 'udt020'
19    Addresses scanned: -
20    Datasheets:
21	http://www.lineagepower.com/oem/pdf/PDT003A0X.pdf
22	http://www.lineagepower.com/oem/pdf/PDT006A0X.pdf
23	http://www.lineagepower.com/oem/pdf/PDT012A0X.pdf
24	http://www.lineagepower.com/oem/pdf/UDT020A0X.pdf
25	http://www.lineagepower.com/oem/pdf/MDT040A0X.pdf
26  * Texas Instruments TPS40400
27    Prefixes: 'tps40400'
28    Addresses scanned: -
29    Datasheets:
30	http://www.ti.com/lit/gpn/tps40400
31  * Generic PMBus devices
32    Prefix: 'pmbus'
33    Addresses scanned: -
34    Datasheet: n.a.
35
36Author: Guenter Roeck <linux@roeck-us.net>
37
38
39Description
40-----------
41
42This driver supports hardware montoring for various PMBus compliant devices.
43It supports voltage, current, power, and temperature sensors as supported
44by the device.
45
46Each monitored channel has its own high and low limits, plus a critical
47limit.
48
49Fan support will be added in a later version of this driver.
50
51
52Usage Notes
53-----------
54
55This driver does not probe for PMBus devices, since there is no register
56which can be safely used to identify the chip (The MFG_ID register is not
57supported by all chips), and since there is no well defined address range for
58PMBus devices. You will have to instantiate the devices explicitly.
59
60Example: the following will load the driver for an LTC2978 at address 0x60
61on I2C bus #1:
62$ modprobe pmbus
63$ echo ltc2978 0x60 > /sys/bus/i2c/devices/i2c-1/new_device
64
65
66Platform data support
67---------------------
68
69Support for additional PMBus chips can be added by defining chip parameters in
70a new chip specific driver file. For example, (untested) code to add support for
71Emerson DS1200 power modules might look as follows.
72
73static struct pmbus_driver_info ds1200_info = {
74	.pages = 1,
75	/* Note: All other sensors are in linear mode */
76	.direct[PSC_VOLTAGE_OUT] = true,
77	.direct[PSC_TEMPERATURE] = true,
78	.direct[PSC_CURRENT_OUT] = true,
79	.m[PSC_VOLTAGE_IN] = 1,
80	.b[PSC_VOLTAGE_IN] = 0,
81	.R[PSC_VOLTAGE_IN] = 3,
82	.m[PSC_VOLTAGE_OUT] = 1,
83	.b[PSC_VOLTAGE_OUT] = 0,
84	.R[PSC_VOLTAGE_OUT] = 3,
85	.m[PSC_TEMPERATURE] = 1,
86	.b[PSC_TEMPERATURE] = 0,
87	.R[PSC_TEMPERATURE] = 3,
88	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_STATUS_INPUT
89		   | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
90		   | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
91		   | PMBUS_HAVE_PIN | PMBUS_HAVE_POUT
92		   | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
93		   | PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12,
94};
95
96static int ds1200_probe(struct i2c_client *client,
97			const struct i2c_device_id *id)
98{
99	return pmbus_do_probe(client, id, &ds1200_info);
100}
101
102static int ds1200_remove(struct i2c_client *client)
103{
104	return pmbus_do_remove(client);
105}
106
107static const struct i2c_device_id ds1200_id[] = {
108	{"ds1200", 0},
109	{}
110};
111
112MODULE_DEVICE_TABLE(i2c, ds1200_id);
113
114/* This is the driver that will be inserted */
115static struct i2c_driver ds1200_driver = {
116	.driver = {
117		   .name = "ds1200",
118		   },
119	.probe = ds1200_probe,
120	.remove = ds1200_remove,
121	.id_table = ds1200_id,
122};
123
124static int __init ds1200_init(void)
125{
126	return i2c_add_driver(&ds1200_driver);
127}
128
129static void __exit ds1200_exit(void)
130{
131	i2c_del_driver(&ds1200_driver);
132}
133
134
135Sysfs entries
136-------------
137
138When probing the chip, the driver identifies which PMBus registers are
139supported, and determines available sensors from this information.
140Attribute files only exist if respective sensors are supported by the chip.
141Labels are provided to inform the user about the sensor associated with
142a given sysfs entry.
143
144The following attributes are supported. Limits are read-write; all other
145attributes are read-only.
146
147inX_input		Measured voltage. From READ_VIN or READ_VOUT register.
148inX_min			Minimum Voltage.
149			From VIN_UV_WARN_LIMIT or VOUT_UV_WARN_LIMIT register.
150inX_max			Maximum voltage.
151			From VIN_OV_WARN_LIMIT or VOUT_OV_WARN_LIMIT register.
152inX_lcrit		Critical minimum Voltage.
153			From VIN_UV_FAULT_LIMIT or VOUT_UV_FAULT_LIMIT register.
154inX_crit		Critical maximum voltage.
155			From VIN_OV_FAULT_LIMIT or VOUT_OV_FAULT_LIMIT register.
156inX_min_alarm		Voltage low alarm. From VOLTAGE_UV_WARNING status.
157inX_max_alarm		Voltage high alarm. From VOLTAGE_OV_WARNING status.
158inX_lcrit_alarm		Voltage critical low alarm.
159			From VOLTAGE_UV_FAULT status.
160inX_crit_alarm		Voltage critical high alarm.
161			From VOLTAGE_OV_FAULT status.
162inX_label		"vin", "vcap", or "voutY"
163
164currX_input		Measured current. From READ_IIN or READ_IOUT register.
165currX_max		Maximum current.
166			From IIN_OC_WARN_LIMIT or IOUT_OC_WARN_LIMIT register.
167currX_lcrit		Critical minimum output current.
168			From IOUT_UC_FAULT_LIMIT register.
169currX_crit		Critical maximum current.
170			From IIN_OC_FAULT_LIMIT or IOUT_OC_FAULT_LIMIT register.
171currX_alarm		Current high alarm.
172			From IIN_OC_WARNING or IOUT_OC_WARNING status.
173currX_max_alarm		Current high alarm.
174			From IIN_OC_WARN_LIMIT or IOUT_OC_WARN_LIMIT status.
175currX_lcrit_alarm	Output current critical low alarm.
176			From IOUT_UC_FAULT status.
177currX_crit_alarm	Current critical high alarm.
178			From IIN_OC_FAULT or IOUT_OC_FAULT status.
179currX_label		"iin" or "ioutY"
180
181powerX_input		Measured power. From READ_PIN or READ_POUT register.
182powerX_cap		Output power cap. From POUT_MAX register.
183powerX_max		Power limit. From PIN_OP_WARN_LIMIT or
184			POUT_OP_WARN_LIMIT register.
185powerX_crit		Critical output power limit.
186			From POUT_OP_FAULT_LIMIT register.
187powerX_alarm		Power high alarm.
188			From PIN_OP_WARNING or POUT_OP_WARNING status.
189powerX_crit_alarm	Output power critical high alarm.
190			From POUT_OP_FAULT status.
191powerX_label		"pin" or "poutY"
192
193tempX_input		Measured temperature.
194			From READ_TEMPERATURE_X register.
195tempX_min		Mimimum temperature. From UT_WARN_LIMIT register.
196tempX_max		Maximum temperature. From OT_WARN_LIMIT register.
197tempX_lcrit		Critical low temperature.
198			From UT_FAULT_LIMIT register.
199tempX_crit		Critical high temperature.
200			From OT_FAULT_LIMIT register.
201tempX_min_alarm		Chip temperature low alarm. Set by comparing
202			READ_TEMPERATURE_X with UT_WARN_LIMIT if
203			TEMP_UT_WARNING status is set.
204tempX_max_alarm		Chip temperature high alarm. Set by comparing
205			READ_TEMPERATURE_X with OT_WARN_LIMIT if
206			TEMP_OT_WARNING status is set.
207tempX_lcrit_alarm	Chip temperature critical low alarm. Set by comparing
208			READ_TEMPERATURE_X with UT_FAULT_LIMIT if
209			TEMP_UT_FAULT status is set.
210tempX_crit_alarm	Chip temperature critical high alarm. Set by comparing
211			READ_TEMPERATURE_X with OT_FAULT_LIMIT if
212			TEMP_OT_FAULT status is set.
213