ASoC: fsl_asrc: Add ASRC ASoC CPU DAI and platform drivers

The Asynchronous Sample Rate Converter (ASRC) converts the sampling rate of a
signal associated with an input clock into a signal associated with a different
output clock. The driver currently works as a Front End of DPCM with other Back
Ends DAI links such as ESAI<->CS42888 and SSI<->WM8962 and SAI. It converts the
original sample rate to a common rate supported by Back Ends for playback while
converts the common rate of Back Ends to a desired rate for capture. It has 3
pairs to support three different substreams within totally 10 channels.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Varka Bhadram <varkabhadram@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/sound/fsl,asrc.txt b/Documentation/devicetree/bindings/sound/fsl,asrc.txt
new file mode 100644
index 000000000000..b93362a570be
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/fsl,asrc.txt
@@ -0,0 +1,60 @@
+Freescale Asynchronous Sample Rate Converter (ASRC) Controller
+
+The Asynchronous Sample Rate Converter (ASRC) converts the sampling rate of a
+signal associated with an input clock into a signal associated with a different
+output clock. The driver currently works as a Front End of DPCM with other Back
+Ends Audio controller such as ESAI, SSI and SAI. It has three pairs to support
+three substreams within totally 10 channels.
+
+Required properties:
+
+  - compatible          : Contains "fsl,imx35-asrc" or "fsl,imx53-asrc".
+
+  - reg                 : Offset and length of the register set for the device.
+
+  - interrupts          : Contains the spdif interrupt.
+
+  - dmas                : Generic dma devicetree binding as described in
+                          Documentation/devicetree/bindings/dma/dma.txt.
+
+  - dma-names           : Contains "rxa", "rxb", "rxc", "txa", "txb" and "txc".
+
+  - clocks              : Contains an entry for each entry in clock-names.
+
+  - clock-names         : Contains the following entries
+        "mem"             Peripheral access clock to access registers.
+        "ipg"             Peripheral clock to driver module.
+        "asrck_<0-f>"     Clock sources for input and output clock.
+
+   - big-endian         : If this property is absent, the little endian mode
+                          will be in use as default. Otherwise, the big endian
+                          mode will be in use for all the device registers.
+
+   - fsl,asrc-rate      : Defines a mutual sample rate used by DPCM Back Ends.
+
+   - fsl,asrc-width     : Defines a mutual sample width used by DPCM Back Ends.
+
+Example:
+
+asrc: asrc@02034000 {
+        compatible = "fsl,imx53-asrc";
+        reg = <0x02034000 0x4000>;
+        interrupts = <0 50 IRQ_TYPE_LEVEL_HIGH>;
+        clocks = <&clks 107>, <&clks 107>, <&clks 0>,
+               <&clks 0>, <&clks 0>, <&clks 0>, <&clks 0>,
+               <&clks 0>, <&clks 0>, <&clks 0>, <&clks 0>,
+               <&clks 0>, <&clks 0>, <&clks 0>, <&clks 0>,
+               <&clks 107>, <&clks 0>, <&clks 0>;
+        clock-names = "mem", "ipg", "asrck0",
+                "asrck_1", "asrck_2", "asrck_3", "asrck_4",
+                "asrck_5", "asrck_6", "asrck_7", "asrck_8",
+                "asrck_9", "asrck_a", "asrck_b", "asrck_c",
+                "asrck_d", "asrck_e", "asrck_f";
+        dmas = <&sdma 17 23 1>, <&sdma 18 23 1>, <&sdma 19 23 1>,
+             <&sdma 20 23 1>, <&sdma 21 23 1>, <&sdma 22 23 1>;
+        dma-names = "rxa", "rxb", "rxc",
+                "txa", "txb", "txc";
+        fsl,asrc-rate  = <48000>;
+        fsl,asrc-width = <16>;
+        status = "okay";
+};