USBD_Audio_DrvStreamStop

Description

Stop record or playback stream.

Files

usbd_audio_drv_<codec-name>.h / usbd_audio_drv_<codec-name>.c

Prototype

static  CPU_BOOLEAN  USBD_Audio_DrvStreamStop (USBD_AUDIO_DRV  *p_audio_drv,
                                               CPU_INT08U       terminal_id_link);

Arguments

p_audio_drv

Pointer to audio driver structure.

terminal_id_link

AudioStreaming terminal link.

Returned Value

DEF_OK, if NO error(s) occurred.

DEF_FAIL, otherwise.

Callers

Audio Class.

Implementation guidelines

This listing shows an example usage of this function handling record and playback streams.

Listing - USBD_Audio_DrvStreamStop() Example Usage

static  CPU_BOOLEAN  USBD_Audio_DrvStreamStop (USBD_AUDIO_DRV  *p_audio_drv,
                                               CPU_INT08U       terminal_id_link)
{
    if (terminal_id_link == Mic_OT_USB_IN_ID) {                                   (1)
	    /* $$$$ Abort ongoing DMA transfer(s). */						          (2)

    	/* $$$$ Disable record operations on audio chip. */			              (3)

    } else if (terminal_id_link == Speaker_IT_USB_OUT_ID) {
	    /* $$$$ Abort ongoing DMA transfer(s). */						          (2)

    	/* $$$$ Disable playback operations on audio chip. */			          (3)
    }

    return (DEF_OK);
}

(1) If the function handles different streams, the terminal ID allows to differentiate them.

(2) Abort ongoing DMA transfer(s). The buffer associated to the DMA transfer may be freed with USBD_Audio_RecordBufFree() or USBD_Audio_PlaybackBufFree into the ISR responsible for DMA data transfer completion.

(3) You may have to disable the record or playback operations on the audio chip. It could be disabling some clocks, disabling some modules, etc. It may require sending a series of I2C commands for registers access,