ASoC: rockchip: support ACODEC for rk3328

This patch adds support for audio CODEC core of rk3328.

Rockchip does not publish detail specification of this core
but driver source code is opened on their GitHub repository.
  https://github.com/rockchip-linux/kernel

So I ported this code to linux-next and added some trivial fixes.

Signed-off-by: Katsuhiro Suzuki <katsuhiro@katsuster.net>
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/rockchip,rk3328-codec.txt

@@ -0,0 +1,23 @@
+* Rockchip Rk3328 internal codec
+
+Required properties:
+
+- compatible: "rockchip,rk3328-codec"
+- reg: physical base address of the controller and length of memory mapped
+  region.
+- rockchip,grf: the phandle of the syscon node for GRF register.
+- clocks: a list of phandle + clock-specifer pairs, one for each entry in clock-names.
+- clock-names: should be "pclk".
+- spk-depop-time-ms: speak depop time msec.
+
+Example for rk3328 internal codec:
+
+codec: codec@ff410000 {
+	compatible = "rockchip,rk3328-codec";
+	reg = <0x0 0xff410000 0x0 0x1000>;
+	rockchip,grf = <&grf>;
+	clocks = <&cru PCLK_ACODEC>;
+	clock-names = "pclk";
+	spk-depop-time-ms = 100;
+	status = "disabled";
+};

sound/soc/codecs/Kconfig

@@ -130,6 +130,7 @@ config SND_SOC_ALL_CODECS
 	select SND_SOC_PCM5102A
 	select SND_SOC_PCM512x_I2C if I2C
 	select SND_SOC_PCM512x_SPI if SPI_MASTER
+	select SND_SOC_RK3328
 	select SND_SOC_RT274 if I2C
 	select SND_SOC_RT286 if I2C
 	select SND_SOC_RT298 if I2C
@@ -806,6 +807,10 @@ config SND_SOC_PCM512x_SPI
 	select SND_SOC_PCM512x
 	select REGMAP_SPI
 
+config SND_SOC_RK3328
+	tristate "Rockchip RK3328 audio CODEC"
+	select REGMAP_MMIO
+
 config SND_SOC_RL6231
 	tristate
 	default y if SND_SOC_RT5514=y

sound/soc/codecs/Makefile

@@ -133,6 +133,7 @@ snd-soc-pcm5102a-objs := pcm5102a.o
 snd-soc-pcm512x-objs := pcm512x.o
 snd-soc-pcm512x-i2c-objs := pcm512x-i2c.o
 snd-soc-pcm512x-spi-objs := pcm512x-spi.o
+snd-soc-rk3328-objs := rk3328_codec.o
 snd-soc-rl6231-objs := rl6231.o
 snd-soc-rl6347a-objs := rl6347a.o
 snd-soc-rt1305-objs := rt1305.o
@@ -400,6 +401,7 @@ obj-$(CONFIG_SND_SOC_PCM5102A)	+= snd-soc-pcm5102a.o
 obj-$(CONFIG_SND_SOC_PCM512x)	+= snd-soc-pcm512x.o
 obj-$(CONFIG_SND_SOC_PCM512x_I2C)	+= snd-soc-pcm512x-i2c.o
 obj-$(CONFIG_SND_SOC_PCM512x_SPI)	+= snd-soc-pcm512x-spi.o
+obj-$(CONFIG_SND_SOC_RK3328)	+= snd-soc-rk3328.o
 obj-$(CONFIG_SND_SOC_RL6231)	+= snd-soc-rl6231.o
 obj-$(CONFIG_SND_SOC_RL6347A)	+= snd-soc-rl6347a.o
 obj-$(CONFIG_SND_SOC_RT1305)	+= snd-soc-rt1305.o