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Add a codec driver for the Cirrus Logic CS48L32 audio DSP. The CS48L32 is a low-power audio DSP with microphone inputs for "Always on Voice" (i.e. voice trigger) and voice command processing. It has a programmable Halo Core DSP and a variety of power-efficient fixed-function audio processors, with configurable digital mixing and routing. There are two I2S/TDM audio serial ports. Four analogue inputs are available through IN1. These feed into a 2-channel ADC through an analogue mux. There is an ALSA control for each IN1 ADC channel to select which analogue input to use. A dedicated digital mic (DMIC) PDM input is available on IN2. Two PDM outputs can feed DMIC inputs on another codec or a host DMIC/PDM input. An on-board regulator provides a power supply or bias voltage to attached microphones. Three switchable MICBIAS outputs are fed from this allowing only the microphone in use to be powered-up. There are DAPM widgets for these outputs: MICBIAS1A, MICBIAS1B and MICBIAS1C. The machine driver must create a DAPM route from the required MICBIAS1x widget to the INn input widgets to make the MICBIAS switch on when the audio input is powered-up. For example if the microphone feeding CS48L32 pin IN1LN_1 is powered from MICBIAS1A, the machine driver must create the path: (sink) IN1LN_1 <----- (source) MICBIAS1A Co-developed-by: Stuart Henderson <stuarth@opensource.cirrus.com> Signed-off-by: Stuart Henderson <stuarth@opensource.cirrus.com> Co-developed-by: Qi Zhou <qi.zhou@cirrus.com> Signed-off-by: Qi Zhou <qi.zhou@cirrus.com> Co-developed-by: Piotr Stankiewicz <piotrs@opensource.cirrus.com> Signed-off-by: Piotr Stankiewicz <piotrs@opensource.cirrus.com> Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> Link: https://patch.msgid.link/20250415115016.505777-3-rf@opensource.cirrus.com Signed-off-by: Mark Brown <broonie@kernel.org>
Linux kernel
============
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