hwmon: (adm1275) Add support for ADM1278

ADM1278 is mostly compatible to other chips of the same series.
Besides the usual difference in coefficients, it supports
a temperature sensor, and it can measure both input and output
voltage at the same time.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation/hwmon/adm1275

@@ -14,6 +14,10 @@ Supported chips:
     Prefix: 'adm1276'
     Addresses scanned: -
     Datasheet: www.analog.com/static/imported-files/data_sheets/ADM1276.pdf
+  * Analog Devices ADM1278
+    Prefix: 'adm1278'
+    Addresses scanned: -
+    Datasheet: www.analog.com/static/imported-files/data_sheets/ADM1278.pdf
   * Analog Devices ADM1293/ADM1294
     Prefix: 'adm1293', 'adm1294'
     Addresses scanned: -
@@ -26,12 +30,14 @@ Description
 -----------
 
 This driver supports hardware monitoring for Analog Devices ADM1075, ADM1275,
-ADM1276, ADM1293, and ADM1294 Hot-Swap Controller and Digital Power Monitors.
+ADM1276, ADM1278, ADM1293, and ADM1294 Hot-Swap Controller and Digital
+Power Monitors.
 
-ADM1075, ADM1275, ADM1276, ADM1293, and ADM1294 are hot-swap controllers that
-allow a circuit board to be removed from or inserted into a live backplane.
-They also feature current and voltage readback via an integrated 12
-bit analog-to-digital converter (ADC), accessed using a PMBus interface.
+ADM1075, ADM1275, ADM1276, ADM1278, ADM1293, and ADM1294 are hot-swap
+controllers that allow a circuit board to be removed from or inserted into
+a live backplane. They also feature current and voltage readback via an
+integrated 12 bit analog-to-digital converter (ADC), accessed using a
+PMBus interface.
 
 The driver is a client driver to the core PMBus driver. Please see
 Documentation/hwmon/pmbus for details on PMBus client drivers.
@@ -96,3 +102,14 @@ power1_reset_history	Write any value to reset history.
 
 			Power attributes are supported on ADM1075, ADM1276,
 			ADM1293, and ADM1294.
+
+temp1_input		Chip temperature.
+			Temperature attributes are only available on ADM1278.
+temp1_max		Maximum chip temperature.
+temp1_max_alarm		Temperature alarm.
+temp1_crit		Critical chip temperature.
+temp1_crit_alarm	Critical temperature high alarm.
+temp1_highest		Highest observed temperature.
+temp1_reset_history	Write any value to reset history.
+
+			Temperature attributes are supported on ADM1278.