ALSA: ac97: add bus binding for codecs

Add the generic ac97 bus binding, especially for ac97 codecs discovered
by ac97 hardware probing.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/Documentation/devicetree/bindings/sound/ac97-bus.txt b/Documentation/devicetree/bindings/sound/ac97-bus.txt
new file mode 100644 (file)
index 0000000..103c428
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/ac97-bus.txt
@@ -0,0 +1,32 @@
+Generic AC97 Device Properties
+
+This documents describes the devicetree bindings for an ac97 controller child
+node describing ac97 codecs.
+
+Required properties:
+-compatible : Must be "ac97,vendor_id1,vendor_id2
+             The ids shall be the 4 characters hexadecimal encoding, such as
+             given by "%04x" formatting of printf
+-reg       : Must be the ac97 codec number, between 0 and 3
+
+Example:
+ac97: sound@40500000 {
+       compatible = "marvell,pxa270-ac97";
+       reg = < 0x40500000 0x1000 >;
+       interrupts = <14>;
+       reset-gpios = <&gpio 95 GPIO_ACTIVE_HIGH>;
+       #sound-dai-cells = <1>;
+       pinctrl-names = "default";
+       pinctrl-0 = < &pinctrl_ac97_default >;
+       clocks = <&clks CLK_AC97>, <&clks CLK_AC97CONF>;
+       clock-names = "AC97CLK", "AC97CONFCLK";
+
+       #address-cells = <1>;
+       #size-cells = <0>;
+       audio-codec@0 {
+               reg = <0>;
+               compatible = "ac97,574d,4c13";
+               clocks = <&fixed_wm9713_clock>;
+               clock-names = "ac97_clk";
+       }
+};