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-rw-r--r--Documentation/hwmon/lm8553
1 files changed, 29 insertions, 24 deletions
diff --git a/Documentation/hwmon/lm85 b/Documentation/hwmon/lm85
index b98e0e0d1910..83cd5bb1ac79 100644
--- a/Documentation/hwmon/lm85
+++ b/Documentation/hwmon/lm85
@@ -14,6 +14,10 @@ Supported chips:
14 Prefix: 'adt7463' 14 Prefix: 'adt7463'
15 Addresses scanned: I2C 0x2c, 0x2d, 0x2e 15 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
16 Datasheet: http://www.onsemi.com/PowerSolutions/product.do?id=ADT7463 16 Datasheet: http://www.onsemi.com/PowerSolutions/product.do?id=ADT7463
17 * Analog Devices ADT7468
18 Prefix: 'adt7468'
19 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
20 Datasheet: http://www.onsemi.com/PowerSolutions/product.do?id=ADT7468
17 * SMSC EMC6D100, SMSC EMC6D101 21 * SMSC EMC6D100, SMSC EMC6D101
18 Prefix: 'emc6d100' 22 Prefix: 'emc6d100'
19 Addresses scanned: I2C 0x2c, 0x2d, 0x2e 23 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
@@ -34,7 +38,7 @@ Description
34----------- 38-----------
35 39
36This driver implements support for the National Semiconductor LM85 and 40This driver implements support for the National Semiconductor LM85 and
37compatible chips including the Analog Devices ADM1027, ADT7463 and 41compatible chips including the Analog Devices ADM1027, ADT7463, ADT7468 and
38SMSC EMC6D10x chips family. 42SMSC EMC6D10x chips family.
39 43
40The LM85 uses the 2-wire interface compatible with the SMBUS 2.0 44The LM85 uses the 2-wire interface compatible with the SMBUS 2.0
@@ -87,14 +91,15 @@ To smooth the response of fans to changes in temperature, the LM85 has an
87optional filter for smoothing temperatures. The ADM1027 has the same 91optional filter for smoothing temperatures. The ADM1027 has the same
88config option but uses it to rate limit the changes to fan speed instead. 92config option but uses it to rate limit the changes to fan speed instead.
89 93
90The ADM1027 and ADT7463 have a 10-bit ADC and can therefore measure 94The ADM1027, ADT7463 and ADT7468 have a 10-bit ADC and can therefore
91temperatures with 0.25 degC resolution. They also provide an offset to the 95measure temperatures with 0.25 degC resolution. They also provide an offset
92temperature readings that is automatically applied during measurement. 96to the temperature readings that is automatically applied during
93This offset can be used to zero out any errors due to traces and placement. 97measurement. This offset can be used to zero out any errors due to traces
94The documentation says that the offset is in 0.25 degC steps, but in 98and placement. The documentation says that the offset is in 0.25 degC
95initial testing of the ADM1027 it was 1.00 degC steps. Analog Devices has 99steps, but in initial testing of the ADM1027 it was 1.00 degC steps. Analog
96confirmed this "bug". The ADT7463 is reported to work as described in the 100Devices has confirmed this "bug". The ADT7463 is reported to work as
97documentation. The current lm85 driver does not show the offset register. 101described in the documentation. The current lm85 driver does not show the
102offset register.
98 103
99See the vendor datasheets for more information. There is application note 104See the vendor datasheets for more information. There is application note
100from National (AN-1260) with some additional information about the LM85. 105from National (AN-1260) with some additional information about the LM85.
@@ -125,17 +130,17 @@ datasheet for a complete description of the differences. Other than
125identifying the chip, the driver behaves no differently with regard to 130identifying the chip, the driver behaves no differently with regard to
126these two chips. The LM85B is recommended for new designs. 131these two chips. The LM85B is recommended for new designs.
127 132
128The ADM1027 and ADT7463 chips have an optional SMBALERT output that can be 133The ADM1027, ADT7463 and ADT7468 chips have an optional SMBALERT output
129used to signal the chipset in case a limit is exceeded or the temperature 134that can be used to signal the chipset in case a limit is exceeded or the
130sensors fail. Individual sensor interrupts can be masked so they won't 135temperature sensors fail. Individual sensor interrupts can be masked so
131trigger SMBALERT. The SMBALERT output if configured replaces one of the other 136they won't trigger SMBALERT. The SMBALERT output if configured replaces one
132functions (PWM2 or IN0). This functionality is not implemented in current 137of the other functions (PWM2 or IN0). This functionality is not implemented
133driver. 138in current driver.
134 139
135The ADT7463 also has an optional THERM output/input which can be connected 140The ADT7463 and ADT7468 also have an optional THERM output/input which can
136to the processor PROC_HOT output. If available, the autofan control 141be connected to the processor PROC_HOT output. If available, the autofan
137dynamic Tmin feature can be enabled to keep the system temperature within 142control dynamic Tmin feature can be enabled to keep the system temperature
138spec (just?!) with the least possible fan noise. 143within spec (just?!) with the least possible fan noise.
139 144
140Configuration Notes 145Configuration Notes
141------------------- 146-------------------
@@ -201,8 +206,8 @@ the temperatures to compensate for systemic errors in the
201measurements. These features are not currently supported by the lm85 206measurements. These features are not currently supported by the lm85
202driver. 207driver.
203 208
204In addition to the ADM1027 features, the ADT7463 also has Tmin control 209In addition to the ADM1027 features, the ADT7463 and ADT7468 also have
205and THERM asserted counts. Automatic Tmin control acts to adjust the 210Tmin control and THERM asserted counts. Automatic Tmin control acts to
206Tmin value to maintain the measured temperature sensor at a specified 211adjust the Tmin value to maintain the measured temperature sensor at a
207temperature. There isn't much documentation on this feature in the 212specified temperature. There isn't much documentation on this feature in
208ADT7463 data sheet. This is not supported by current driver. 213the ADT7463 data sheet. This is not supported by current driver.