ad525x_dpot: new driver for AD525x digital potentiometers

This driver supports the non-volatile digital potentiometers via I2C:
AD5258, AD5259, AD5251, AD5252, AD5253, AD5254, and AD5255

It provides a sysfs interface to each device for reading/writing which
is documented in Documentation/misc-devices/ad525x_dpot.txt.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Chris Verges <chrisv@cyberswitching.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 2c16ca6..0c7f4c5 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -13,6 +13,20 @@
 
 if MISC_DEVICES
 
+config AD525X_DPOT
+	tristate "Analog Devices AD525x Digital Potentiometers"
+	depends on I2C && SYSFS
+	help
+	  If you say yes here, you get support for the Analog Devices
+	  AD5258, AD5259, AD5251, AD5252, AD5253, AD5254 and AD5255
+	  digital potentiometer chips.
+
+	  See Documentation/misc-devices/ad525x_dpot.txt for the
+	  userspace interface.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called ad525x_dpot.
+
 config ATMEL_PWM
 	tristate "Atmel AT32/AT91 PWM support"
 	depends on AVR32 || ARCH_AT91SAM9263 || ARCH_AT91SAM9RL || ARCH_AT91CAP9