f00f846fe3
The sample illustrates how to calculate feedback value based on I2S sample clock measurement or indirect I2S FRAMESTART and USBD SOF. The sample is currently only supported on nrf5340dk_nrf5340_cpuapp target because the feedback measurement uses target specific peripherals. While it should be possible to perform feedback value calculation entirely in software (possibly with some additional filtering due to software scheduling jitter), the I2S API does not provide necessary timestamps. Signed-off-by: Tomasz Moń <tomasz.mon@nordicsemi.no>
45 lines
1,017 B
Plaintext
45 lines
1,017 B
Plaintext
/*
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* Copyright (c) 2023 Nordic Semiconductor ASA
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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#include <dt-bindings/usb/audio.h>
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/ {
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uac2_headphones: usb_audio2 {
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compatible = "zephyr,uac2";
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status = "okay";
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audio-function = <AUDIO_FUNCTION_OTHER>;
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uac_aclk: aclk {
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compatible = "zephyr,uac2-clock-source";
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clock-type = "internal-programmable";
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frequency-control = "host-programmable";
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sampling-frequencies = <48000>;
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};
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out_terminal: out_terminal {
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compatible = "zephyr,uac2-input-terminal";
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clock-source = <&uac_aclk>;
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terminal-type = <USB_TERMINAL_STREAMING>;
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front-left;
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front-right;
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};
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headphones_output: headphones {
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compatible = "zephyr,uac2-output-terminal";
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data-source = <&out_terminal>;
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clock-source = <&uac_aclk>;
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terminal-type = <OUTPUT_TERMINAL_HEADPHONES>;
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};
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as_iso_out: out_interface {
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compatible = "zephyr,uac2-audio-streaming";
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linked-terminal = <&out_terminal>;
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subslot-size = <2>;
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bit-resolution = <16>;
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};
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};
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};
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