hwmon: add Maxim MAX197 support

The MAX197 is an A/D converter, made by Maxim. This driver currently
supports the MAX197, and MAX199. They are both 8-Channel, Multi-Range,
5V, 12-Bit DAS with 8+4 Bus Interface and Fault Protection.

The available ranges for the MAX197 are {0,-5V} to 5V, and {0,-10V} to
10V, while they are {0,-2V} to 2V, and {0,-4V} to 4V on the MAX199.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index f50cb44..6566ed6 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -813,6 +813,15 @@
 	  This driver can also be built as a module.  If so, the module
 	  will be called max1668.
 
+config SENSORS_MAX197
+	tristate "Maxim MAX197 and compatibles"
+	help
+	  Support for the Maxim MAX197 A/D converter.
+	  Support will include, but not be limited to, MAX197, and MAX199.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called max197.
+
 config SENSORS_MAX6639
 	tristate "Maxim MAX6639 sensor chip"
 	depends on I2C && EXPERIMENTAL