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authorMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-04-17 06:46:29 -0300
committerGuenter Roeck <linux@roeck-us.net>2019-04-17 10:37:23 -0700
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docs: hwmon: Add an index file and rename docs to *.rst
Now that all files were converted to ReST format, rename them and add an index. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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+Kernel driver emc1403
+=====================
+
+Supported chips:
+
+ * SMSC / Microchip EMC1402, EMC1412
+
+ Addresses scanned: I2C 0x18, 0x1c, 0x29, 0x4c, 0x4d, 0x5c
+
+ Prefix: 'emc1402'
+
+ Datasheets:
+
+ - http://ww1.microchip.com/downloads/en/DeviceDoc/1412.pdf
+ - http://ww1.microchip.com/downloads/en/DeviceDoc/1402.pdf
+
+ * SMSC / Microchip EMC1403, EMC1404, EMC1413, EMC1414
+
+ Addresses scanned: I2C 0x18, 0x29, 0x4c, 0x4d
+
+ Prefix: 'emc1403', 'emc1404'
+
+ Datasheets:
+
+ - http://ww1.microchip.com/downloads/en/DeviceDoc/1403_1404.pdf
+ - http://ww1.microchip.com/downloads/en/DeviceDoc/1413_1414.pdf
+
+ * SMSC / Microchip EMC1422
+
+ Addresses scanned: I2C 0x4c
+
+ Prefix: 'emc1422'
+
+ Datasheet:
+
+ - http://ww1.microchip.com/downloads/en/DeviceDoc/1422.pdf
+
+ * SMSC / Microchip EMC1423, EMC1424
+
+ Addresses scanned: I2C 0x4c
+
+ Prefix: 'emc1423', 'emc1424'
+
+ Datasheet:
+
+ - http://ww1.microchip.com/downloads/en/DeviceDoc/1423_1424.pdf
+
+Author:
+ Kalhan Trisal <kalhan.trisal@intel.com
+
+
+Description
+-----------
+
+The Standard Microsystems Corporation (SMSC) / Microchip EMC14xx chips
+contain up to four temperature sensors. EMC14x2 support two sensors
+(one internal, one external). EMC14x3 support three sensors (one internal,
+two external), and EMC14x4 support four sensors (one internal, three
+external).
+
+The chips implement three limits for each sensor: low (tempX_min), high
+(tempX_max) and critical (tempX_crit.) The chips also implement an
+hysteresis mechanism which applies to all limits. The relative difference
+is stored in a single register on the chip, which means that the relative
+difference between the limit and its hysteresis is always the same for
+all three limits.
+
+This implementation detail implies the following:
+
+* When setting a limit, its hysteresis will automatically follow, the
+ difference staying unchanged. For example, if the old critical limit
+ was 80 degrees C, and the hysteresis was 75 degrees C, and you change
+ the critical limit to 90 degrees C, then the hysteresis will
+ automatically change to 85 degrees C.
+* The hysteresis values can't be set independently. We decided to make
+ only temp1_crit_hyst writable, while all other hysteresis attributes
+ are read-only. Setting temp1_crit_hyst writes the difference between
+ temp1_crit_hyst and temp1_crit into the chip, and the same relative
+ hysteresis applies automatically to all other limits.
+* The limits should be set before the hysteresis.