hwmon: (lm70) Add TI TMP121 support

The Texas Instruments TMP121 is a SPI temperature sensor very similar
to the LM70, with slightly higher resolution.  This patch extends the
LM70 driver to support the TMP121.  The TMP123 differs in pin assign-
ment.

Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/Documentation/hwmon/lm70 b/Documentation/hwmon/lm70
index b8d1a52..0d24029 100644
--- a/Documentation/hwmon/lm70
+++ b/Documentation/hwmon/lm70
@@ -1,9 +1,11 @@
 Kernel driver lm70
 ==================
 
-Supported chip:
+Supported chips:
   * National Semiconductor LM70
     Datasheet: http://www.national.com/pf/LM/LM70.html
+  * Texas Instruments TMP121/TMP123
+    Information: http://focus.ti.com/docs/prod/folders/print/tmp121.html
 
 Author:
         Kaiwan N Billimoria <kaiwan@designergraphix.com>
@@ -29,6 +31,10 @@
 with a "SPI master controller driver", see drivers/spi/spi_lm70llp.c
 and its associated documentation.
 
+The TMP121/TMP123 are very similar; main differences are 4 wire SPI inter-
+face (read only) and 13-bit temperature data (0.0625 degrees celsius reso-
+lution).
+
 Thanks to
 ---------
 Jean Delvare <khali@linux-fr.org> for mentoring the hwmon-side driver