ASoC: tegra: Add Tegra186 based ASRC driver

Asynchronous Sample Rate Converter (ASRC) converts the sampling frequency
of the input signal from one frequency to another. It can handle over a
wide range of sample rate ratios (freq_in/freq_out) from 1:24 to 24:1.

ASRC has two modes of operation. One where ratio can be programmed in SW
and the other where it gets the information from ratio estimator module.
The latter mode above can help address the cases where the sample rate is
not known at the stream set up time or is potentially time varying.
In addition, the ratio between input and output sample rate can be any
arbitrary number and the input and output clocks could be derived from
asynchronous clocks.

This patch registers ASRC driver with ASoC framework. The component driver
exposes DAPM widgets, routes and kcontrols for the device. The DAI driver
exposes ASRC interfaces, which can be used to connect different components
in the ASoC layer. Makefile and Kconfig support is added to allow build
the driver.

Signed-off-by: Sameer Pujar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mark Brown <[email protected]>

sound/soc/tegra/Kconfig

@@ -85,6 +85,18 @@ config SND_SOC_TEGRA210_I2S
 	  compatible devices.
 	  Say Y or M if you want to add support for Tegra210 I2S module.
 
+config SND_SOC_TEGRA186_ASRC
+	tristate "Tegra186 ASRC module"
+	help
+	  Config to enable the Asynchronous Sample Rate Converter (ASRC),
+	  which converts the sampling frequency of the input signal from
+	  one frequency to another. It can handle over a wide range of
+	  sample rate ratios (freq_in/freq_out) from 1:24 to 24:1.
+	  ASRC has two modes of operation. One where ratio can be programmed
+	  in SW and the other where it gets information from ratio estimator
+	  module.
+	  Say Y or M if you want to add support for Tegra186 ASRC module.
+
 config SND_SOC_TEGRA186_DSPK
 	tristate "Tegra186 DSPK module"
 	help

sound/soc/tegra/Makefile

@@ -11,6 +11,7 @@ snd-soc-tegra30-i2s-objs := tegra30_i2s.o
 snd-soc-tegra210-ahub-objs := tegra210_ahub.o
 snd-soc-tegra210-dmic-objs := tegra210_dmic.o
 snd-soc-tegra210-i2s-objs := tegra210_i2s.o
+snd-soc-tegra186-asrc-objs := tegra186_asrc.o
 snd-soc-tegra186-dspk-objs := tegra186_dspk.o
 snd-soc-tegra210-admaif-objs := tegra210_admaif.o
 snd-soc-tegra210-mvc-objs := tegra210_mvc.o
@@ -29,6 +30,7 @@ obj-$(CONFIG_SND_SOC_TEGRA30_I2S) += snd-soc-tegra30-i2s.o
 obj-$(CONFIG_SND_SOC_TEGRA210_DMIC) += snd-soc-tegra210-dmic.o
 obj-$(CONFIG_SND_SOC_TEGRA210_AHUB) += snd-soc-tegra210-ahub.o
 obj-$(CONFIG_SND_SOC_TEGRA210_I2S) += snd-soc-tegra210-i2s.o
+obj-$(CONFIG_SND_SOC_TEGRA186_ASRC) += snd-soc-tegra186-asrc.o
 obj-$(CONFIG_SND_SOC_TEGRA186_DSPK) += snd-soc-tegra186-dspk.o
 obj-$(CONFIG_SND_SOC_TEGRA210_ADMAIF) += snd-soc-tegra210-admaif.o
 obj-$(CONFIG_SND_SOC_TEGRA210_MVC) += snd-soc-tegra210-mvc.o