Samsung Exynos SoC Low Power Audio Subsystem (LPASS)

Required properties:

 - compatible		: "samsung,exynos5433-lpass"
 - reg			: should contain the LPASS top SFR region location
			  and size
 - clock-names		: should contain following required clocks: "sfr0_ctrl"
 - clocks		: should contain clock specifiers of all clocks, which
			  input names have been specified in clock-names
			  property, in same order.
 - #address-cells	: should be 1
 - #size-cells		: should be 1
 - ranges		: must be present

Each IP block of the Low Power Audio Subsystem should be specified as
an optional sub-node. For "samsung,exynos5433-lpass" compatible this includes:
UART, SLIMBUS, PCM, I2S, DMAC, Timers 0...4, VIC, WDT 0...1 devices.

Bindings of the sub-nodes are described in:
  ../serial/samsung_uart.yaml
  ../sound/samsung-i2s.txt
  ../dma/arm-pl330.txt


Example:

audio-subsystem {
	compatible = "samsung,exynos5433-lpass";
	reg = <0x11400000 0x100>, <0x11500000 0x08>;
	clocks = <&cmu_aud CLK_PCLK_SFR0_CTRL>;
	clock-names = "sfr0_ctrl";
	#address-cells = <1>;
	#size-cells = <1>;
	ranges;

	adma: adma@11420000 {
		compatible = "arm,pl330", "arm,primecell";
		reg = <0x11420000 0x1000>;
		interrupts = <0 73 0>;
		clocks = <&cmu_aud CLK_ACLK_DMAC>;
		clock-names = "apb_pclk";
		#dma-cells = <1>;
		#dma-channels = <8>;
		#dma-requests = <32>;
	};

	i2s0: i2s0@11440000 {
		compatible = "samsung,exynos7-i2s";
		reg = <0x11440000 0x100>;
		dmas = <&adma 0 &adma 2>;
		dma-names = "tx", "rx";
		interrupts = <0 70 0>;
		clocks = <&cmu_aud CLK_PCLK_AUD_I2S>,
			 <&cmu_aud CLK_SCLK_AUD_I2S>,
			 <&cmu_aud CLK_SCLK_I2S_BCLK>;
		clock-names = "iis", "i2s_opclk0", "i2s_opclk1";
		pinctrl-names = "default";
		pinctrl-0 = <&i2s0_bus>;
	};

	serial_3: serial@11460000 {
		compatible = "samsung,exynos5433-uart";
		reg = <0x11460000 0x100>;
		interrupts = <0 67 0>;
		clocks = <&cmu_aud CLK_PCLK_AUD_UART>,
			 <&cmu_aud CLK_SCLK_AUD_UART>;
		clock-names = "uart", "clk_uart_baud0";
		pinctrl-names = "default";
		pinctrl-0 = <&uart_aud_bus>;
	};
 };
