ASoC: Add WM8974 CODEC driver

The WM8974 is a low power, high quality mono CODEC designed for portable
applications such as digital still cameras or digital voice recorders.

This driver was originally written by Graeme Gregory and Liam Girdwood
and has since been maintained by myself with some updates contributed by
Brett Saunders and Javier Martin.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/Kconfig

@@ -38,6 +38,7 @@ config SND_SOC_ALL_CODECS
 	select SND_SOC_WM8940 if I2C
 	select SND_SOC_WM8960 if I2C
 	select SND_SOC_WM8971 if I2C
+	select SND_SOC_WM8974 if I2C
 	select SND_SOC_WM8988 if SND_SOC_I2C_AND_SPI
 	select SND_SOC_WM8990 if I2C
 	select SND_SOC_WM9081 if I2C
@@ -151,6 +152,9 @@ config SND_SOC_WM8960
 config SND_SOC_WM8971
 	tristate
 
+config SND_SOC_WM8974
+	tristate
+
 config SND_SOC_WM8988
 	tristate
 

sound/soc/codecs/Makefile

@@ -26,6 +26,7 @@ snd-soc-wm8903-objs := wm8903.o
 snd-soc-wm8940-objs := wm8940.o
 snd-soc-wm8960-objs := wm8960.o
 snd-soc-wm8971-objs := wm8971.o
+snd-soc-wm8974-objs := wm8974.o
 snd-soc-wm8988-objs := wm8988.o
 snd-soc-wm8990-objs := wm8990.o
 snd-soc-wm9081-objs := wm9081.o
@@ -59,6 +60,7 @@ obj-$(CONFIG_SND_SOC_WM8753)	+= snd-soc-wm8753.o
 obj-$(CONFIG_SND_SOC_WM8900)	+= snd-soc-wm8900.o
 obj-$(CONFIG_SND_SOC_WM8903)	+= snd-soc-wm8903.o
 obj-$(CONFIG_SND_SOC_WM8971)	+= snd-soc-wm8971.o
+obj-$(CONFIG_SND_SOC_WM8974)	+= snd-soc-wm8974.o
 obj-$(CONFIG_SND_SOC_WM8940)	+= snd-soc-wm8940.o
 obj-$(CONFIG_SND_SOC_WM8960)	+= snd-soc-wm8960.o
 obj-$(CONFIG_SND_SOC_WM8988)	+= snd-soc-wm8988.o