hwmon: (adt7410) Add support for the adt7310/adt7320

The adt7310/adt7320 is the SPI version of the adt7410/adt7420. The register map
layout is a bit different, i.e. the register addresses differ between the two
variants, but the bit layouts of the individual registers are identical. So both
chip variants can easily be supported by the same driver. The issue of non
matching register address layouts is solved by a simple look-up table which
translates the I2C addresses to the SPI addresses.

The patch moves the bulk of the adt7410 driver to a common module that will be
shared by the adt7410 and adt7310 drivers. This common module implements the
driver logic and uses a set of virtual functions to perform IO access. The
adt7410 and adt7310 driver modules provide proper implementations of these IO
accessor functions for I2C respective SPI.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 30 insertions, 17 deletions

diff --git a/Documentation/hwmon/adt7410 b/Documentation/hwmon/adt7410
index 58150c480e5..9817941e5f1 100644
--- a/Documentation/hwmon/adt7410
+++ b/Documentation/hwmon/adt7410
@@ -12,29 +12,42 @@ Supported chips:
     Addresses scanned: None
     Datasheet: Publicly available at the Analog Devices website
                http://www.analog.com/static/imported-files/data_sheets/ADT7420.pdf
+  * Analog Devices ADT7310
+    Prefix: 'adt7310'
+    Addresses scanned: None
+    Datasheet: Publicly available at the Analog Devices website
+               http://www.analog.com/static/imported-files/data_sheets/ADT7310.pdf
+  * Analog Devices ADT7320
+    Prefix: 'adt7320'
+    Addresses scanned: None
+    Datasheet: Publicly available at the Analog Devices website
+               http://www.analog.com/static/imported-files/data_sheets/ADT7320.pdf
 
 Author: Hartmut Knaack <knaack.h@gmx.de>
 
 Description
 -----------
 
-The ADT7410 is a temperature sensor with rated temperature range of -55°C to
-+150°C. It has a high accuracy of +/-0.5°C and can be operated at a resolution
-of 13 bits (0.0625°C) or 16 bits (0.0078°C). The sensor provides an INT pin to
-indicate that a minimum or maximum temperature set point has been exceeded, as
-well as a critical temperature (CT) pin to indicate that the critical
-temperature set point has been exceeded. Both pins can be set up with a common
-hysteresis of 0°C - 15°C and a fault queue, ranging from 1 to 4 events. Both
-pins can individually set to be active-low or active-high, while the whole
-device can either run in comparator mode or interrupt mode. The ADT7410
-supports continous temperature sampling, as well as sampling one temperature
-value per second or even justget one sample on demand for power saving.
-Besides, it can completely power down its ADC, if power management is
-required.
-
-The ADT7420 is register compatible, the only differences being the package,
-a slightly narrower operating temperature range (-40°C to +150°C), and a
-better accuracy (0.25°C instead of 0.50°C.)
+The ADT7310/ADT7410 is a temperature sensor with rated temperature range of
+-55°C to +150°C. It has a high accuracy of +/-0.5°C and can be operated at a
+resolution of 13 bits (0.0625°C) or 16 bits (0.0078°C). The sensor provides an
+INT pin to indicate that a minimum or maximum temperature set point has been
+exceeded, as well as a critical temperature (CT) pin to indicate that the
+critical temperature set point has been exceeded. Both pins can be set up with a
+common hysteresis of 0°C - 15°C and a fault queue, ranging from 1 to 4 events.
+Both pins can individually set to be active-low or active-high, while the whole
+device can either run in comparator mode or interrupt mode. The ADT7410 supports
+continuous temperature sampling, as well as sampling one temperature value per
+second or even just get one sample on demand for power saving. Besides, it can
+completely power down its ADC, if power management is required.
+
+The ADT7320/ADT7420 is register compatible, the only differences being the
+package, a slightly narrower operating temperature range (-40°C to +150°C), and
+a better accuracy (0.25°C instead of 0.50°C.)
+
+The difference between the ADT7310/ADT7320 and ADT7410/ADT7420 is the control
+interface, the ADT7310 and ADT7320 use SPI while the ADT7410 and ADT7420 use
+I2C.
 
 Configuration Notes
 -------------------