Re: [PATCH][LINUX][ALSA][USB AUDIO CLASS 1] wrong channel ids for surround

[Takashi Iwai <tiwai@suse.de>]

On Thu, 25 Jul 2024 13:08:20 +0200,
Sylvain BERTRAND wrote:
> 
> Hi,
> 
> In the USB audio class 1 specifications, page 33 (3.7.2.3 Audio Channel Cluster Format):
> 
> Surround is spatially defined as [rear], hence left surround should be SNDRV_CHMAP_RL and not SND_CHMAP_SL (Side).
> Same for right surround channel.
> 
> Right?

Yes, this looks rather like a typo, SL/SR appear twice there.

> 
> I am not a mailing list subscriber, CC me please.
> 
> regards,

Could you submit a properly formatted patch (with a patch description
and your Signed-off-by tag) to linux-sound ML
(linux-sound@vger.kernel.org) instead?


thanks,

Takashi


> 
> -- 
> Sylvain BERTRAND
> 
> 
> --- a/sound/usb/stream.c
> +++ b/sound/usb/stream.c
> @@ -244,8 +244,8 @@ static struct snd_pcm_chmap_elem *convert_chmap(int channels, unsigned int bits,
>  		SNDRV_CHMAP_FR,		/* right front */
>  		SNDRV_CHMAP_FC,		/* center front */
>  		SNDRV_CHMAP_LFE,	/* LFE */
> -		SNDRV_CHMAP_SL,		/* left surround */
> -		SNDRV_CHMAP_SR,		/* right surround */
> +		SNDRV_CHMAP_RL,		/* left surround */
> +		SNDRV_CHMAP_RR,		/* right surround */
>  		SNDRV_CHMAP_FLC,	/* left of center */
>  		SNDRV_CHMAP_FRC,	/* right of center */
>  		SNDRV_CHMAP_RC,		/* surround */
>