iio: dac: Add AD5758 support

The AD5758 is a single channel DAC with 16-bit precision which uses the
SPI interface that operates at clock rates up to 50MHz.

The output can be configured as voltage or current and is available on a
single terminal.

Datasheet:
http://www.analog.com/media/en/technical-documentation/data-sheets/ad5758.pdf

Signed-off-by: Stefan Popa <stefan.popa@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

MAINTAINERS

@@ -796,6 +796,13 @@ M:	Michael Hanselmann <linux-kernel@hansmi.ch>
 S:	Supported
 F:	drivers/macintosh/ams/
 
+ANALOG DEVICES INC AD5758 DRIVER
+M:	Stefan Popa <stefan.popa@analog.com>
+L:	linux-iio@vger.kernel.org
+W:	http://ez.analog.com/community/linux-device-drivers
+S:	Supported
+F:	drivers/iio/dac/ad5758.c
+
 ANALOG DEVICES INC AD5686 DRIVER
 M:	Stefan Popa <stefan.popa@analog.com>
 L:	linux-pm@vger.kernel.org

drivers/iio/dac/Kconfig

@@ -167,6 +167,16 @@ config AD5755
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad5755.
 
+config AD5758
+	tristate "Analog Devices AD5758 DAC driver"
+	depends on SPI_MASTER
+	help
+	  Say yes here to build support for Analog Devices AD5758 single channel
+	  Digital to Analog Converter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad5758.
+
 config AD5761
 	tristate "Analog Devices AD5761/61R/21/21R DAC driver"
 	depends on SPI_MASTER

drivers/iio/dac/Makefile

@@ -16,6 +16,7 @@ obj-$(CONFIG_AD5592R_BASE) += ad5592r-base.o
 obj-$(CONFIG_AD5592R) += ad5592r.o
 obj-$(CONFIG_AD5593R) += ad5593r.o
 obj-$(CONFIG_AD5755) += ad5755.o
+obj-$(CONFIG_AD5755) += ad5758.o
 obj-$(CONFIG_AD5761) += ad5761.o
 obj-$(CONFIG_AD5764) += ad5764.o
 obj-$(CONFIG_AD5791) += ad5791.o