Re: [PATCH v7 2/7] ALSA: Add definitions for the bits in IEC958 subframe

[Simona Vetter <simona.vetter@ffwll.ch>]

On Tue, Sep 23, 2025 at 01:29:56PM +0800, Shengjiu Wang wrote:
> The IEC958 subframe format SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE are used
> in HDMI and DisplayPort to describe the audio stream, but hardware device
> may need to reorder the IEC958 bits for internal transmission, so need
> these standard bits definitions for IEC958 subframe format.
> 
> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
> Reviewed-by: Takashi Iwai <tiwai@suse.de>
> Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>

Would be good to get a formal ack from alsa maintainers before merging
through drm, just to be sure.

Thanks, Sima

> ---
>  include/sound/asoundef.h | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/include/sound/asoundef.h b/include/sound/asoundef.h
> index 09b2c3dffb30..c4a929d4fd51 100644
> --- a/include/sound/asoundef.h
> +++ b/include/sound/asoundef.h
> @@ -12,6 +12,15 @@
>   *        Digital audio interface					    *
>   *                                                                          *
>   ****************************************************************************/
> +/* IEC958 subframe format */
> +#define IEC958_SUBFRAME_PREAMBLE_MASK	(0xfU)
> +#define IEC958_SUBFRAME_AUXILIARY_MASK	(0xfU << 4)
> +#define IEC958_SUBFRAME_SAMPLE_24_MASK	(0xffffffU << 4)
> +#define IEC958_SUBFRAME_SAMPLE_20_MASK	(0xfffffU << 8)
> +#define IEC958_SUBFRAME_VALIDITY	(0x1U << 28)
> +#define IEC958_SUBFRAME_USER_DATA	(0x1U << 29)
> +#define IEC958_SUBFRAME_CHANNEL_STATUS	(0x1U << 30)
> +#define IEC958_SUBFRAME_PARITY		(0x1U << 31)
>  
>  /* AES/IEC958 channel status bits */
>  #define IEC958_AES0_PROFESSIONAL	(1<<0)	/* 0 = consumer, 1 = professional */
> -- 
> 2.34.1
> 

-- 
Simona Vetter
Software Engineer
http://blog.ffwll.ch