[alsa-devel] [PATCH] ALSA: core: Add 384kHz Support

[Takashi Iwai]

On Wed, 27 Jan 2016 14:53:45 +0100,
<brian.austin at cirrus.com> wrote:
> 
> From: Brian Austin <brian.austin at cirrus.com>
> 
> Adding support for 384kHz audio sample rates

The most important information is missing: why this is needed.

(Note that the support of 384kHz itself can be done without this
 addition :) 


Takashi

> 
> Signed-off-by: Brian Austin <brian.austin at cirrus.com>
> ---
>  include/sound/pcm.h     | 3 +++
>  sound/core/pcm_native.c | 4 ++--
>  2 files changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/include/sound/pcm.h b/include/sound/pcm.h
> index b0be092..050c0b7 100644
> --- a/include/sound/pcm.h
> +++ b/include/sound/pcm.h
> @@ -129,6 +129,7 @@ struct snd_pcm_ops {
>  #define SNDRV_PCM_RATE_96000		(1<<10)		/* 96000Hz */
>  #define SNDRV_PCM_RATE_176400		(1<<11)		/* 176400Hz */
>  #define SNDRV_PCM_RATE_192000		(1<<12)		/* 192000Hz */
> +#define SNDRV_PCM_RATE_384000		(1<<13)		/* 384000Hz */
>  
>  #define SNDRV_PCM_RATE_CONTINUOUS	(1<<30)		/* continuous range */
>  #define SNDRV_PCM_RATE_KNOT		(1<<31)		/* supports more non-continuos rates */
> @@ -141,6 +142,8 @@ struct snd_pcm_ops {
>  					 SNDRV_PCM_RATE_88200|SNDRV_PCM_RATE_96000)
>  #define SNDRV_PCM_RATE_8000_192000	(SNDRV_PCM_RATE_8000_96000|SNDRV_PCM_RATE_176400|\
>  					 SNDRV_PCM_RATE_192000)
> +#define SNDRV_PCM_RATE_8000_384000	(SNDRV_PCM_RATE_8000_192000|SNDRV_PCM_RATE_384000)
> +
>  #define _SNDRV_PCM_FMTBIT(fmt)		(1ULL << (__force int)SNDRV_PCM_FORMAT_##fmt)
>  #define SNDRV_PCM_FMTBIT_S8		_SNDRV_PCM_FMTBIT(S8)
>  #define SNDRV_PCM_FMTBIT_U8		_SNDRV_PCM_FMTBIT(U8)
> diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
> index a8b27cd..2e10c3f 100644
> --- a/sound/core/pcm_native.c
> +++ b/sound/core/pcm_native.c
> @@ -1969,12 +1969,12 @@ static int snd_pcm_hw_rule_sample_bits(struct snd_pcm_hw_params *params,
>  	return snd_interval_refine(hw_param_interval(params, rule->var), &t);
>  }
>  
> -#if SNDRV_PCM_RATE_5512 != 1 << 0 || SNDRV_PCM_RATE_192000 != 1 << 12
> +#if SNDRV_PCM_RATE_5512 != 1 << 0 || SNDRV_PCM_RATE_384000 != 1 << 13
>  #error "Change this table"
>  #endif
>  
>  static unsigned int rates[] = { 5512, 8000, 11025, 16000, 22050, 32000, 44100,
> -                                 48000, 64000, 88200, 96000, 176400, 192000 };
> +			48000, 64000, 88200, 96000, 176400, 192000, 384000 };
>  
>  const struct snd_pcm_hw_constraint_list snd_pcm_known_rates = {
>  	.count = ARRAY_SIZE(rates),
> -- 
> 1.9.1
>