Re: [PATCH 1/3] ALSA: pcm: Add missing formats to formats list

[Amadeusz Sławiński <amadeuszx.slawinski@xxxxxxxxxxxxxxx>]

On 1/25/2024 11:35 PM, Ivan Orlov wrote:
> Add 4 missing formats to 'snd_pcm_format_names' array in order to be
> able to get their names with 'snd_pcm_format_name' function.
>
> Signed-off-by: Ivan Orlov <ivan.orlov0322@xxxxxxxxx>
> ---
>   sound/core/pcm.c | 4 ++++
>   1 file changed, 4 insertions(+)
>
> diff --git a/sound/core/pcm.c b/sound/core/pcm.c
> index a09f0154e6a7..d0788126cbab 100644
> --- a/sound/core/pcm.c
> +++ b/sound/core/pcm.c
> @@ -211,6 +211,10 @@ static const char * const snd_pcm_format_names[] = {
>   	FORMAT(DSD_U32_LE),
>   	FORMAT(DSD_U16_BE),
>   	FORMAT(DSD_U32_BE),
> +	FORMAT(S20_LE),
> +	FORMAT(S20_BE),
> +	FORMAT(U20_LE),
> +	FORMAT(U20_BE),
>   };
>   
>   /**

Maybe we can also add some kind of static_assert to check at compile 
time that all formats are handled, something like:
static_assert(ARRAY_SIZE(snd_pcm_format_names) == SNDRV_PCM_FORMAT_LAST 
+ 1);

Although looking at definitions there is a hole between 
SNDRV_PCM_FORMAT_U20_BE & SNDRV_PCM_FORMAT_SPECIAL, which will cause 
this idea to fail.

Perhaps with comment:
static_assert(ARRAY_SIZE(snd_pcm_format_names) == SNDRV_PCM_FORMAT_LAST 
+ 1 - 2); /* -2 for formats reserved for future use */
?