diff options
| author | Jaroslav Kysela <perex@perex.cz> | 2023-11-17 13:05:55 +0100 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2023-11-27 17:24:26 +0100 |
| commit | 2112aa034907c428785e1a5730927181276ee45b (patch) | |
| tree | c75e6907ab964064ba449d4b716109fcfce1d597 /include/sound | |
| parent | 26257869672fd4a06a60c2da841e15fb2cb47bbe (diff) | |
ALSA: pcm: Introduce MSBITS subformat interface
Improve granularity of format selection for S32/U32 formats by adding
constants representing 20, 24 and MAX most significant bits.
The MAX means the maximum number of significant bits which can
the physical format hold. For 32-bit formats, MAX is related
to 32 bits. For 8-bit formats, MAX is related to 8 bits etc.
As there is only one user currently (format S32_LE), subformat is
represented by a simple u32 and stores flags only for that one user
alone. The approach of subformat being part of struct snd_pcm_hardware
is a compromise between ALSA and ASoC allowing for
hw_params-intersection code to be alloc/free-less while not adding any
new responsibilities to ASoC runtime structures.
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Co-developed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Link: https://lore.kernel.org/r/20231117120610.1755254-2-cezary.rojewski@intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'include/sound')
| -rw-r--r-- | include/sound/pcm.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/include/sound/pcm.h b/include/sound/pcm.h index 2a815373dac1..cc175c623dac 100644 --- a/include/sound/pcm.h +++ b/include/sound/pcm.h @@ -32,6 +32,7 @@ struct snd_pcm_hardware { unsigned int info; /* SNDRV_PCM_INFO_* */ u64 formats; /* SNDRV_PCM_FMTBIT_* */ + u32 subformats; /* for S32_LE, SNDRV_PCM_SUBFMTBIT_* */ unsigned int rates; /* SNDRV_PCM_RATE_* */ unsigned int rate_min; /* min rate */ unsigned int rate_max; /* max rate */ @@ -217,6 +218,12 @@ struct snd_pcm_ops { #define SNDRV_PCM_FMTBIT_U20 SNDRV_PCM_FMTBIT_U20_BE #endif +#define _SNDRV_PCM_SUBFMTBIT(fmt) BIT((__force int)SNDRV_PCM_SUBFORMAT_##fmt) +#define SNDRV_PCM_SUBFMTBIT_STD _SNDRV_PCM_SUBFMTBIT(STD) +#define SNDRV_PCM_SUBFMTBIT_MSBITS_MAX _SNDRV_PCM_SUBFMTBIT(MSBITS_MAX) +#define SNDRV_PCM_SUBFMTBIT_MSBITS_20 _SNDRV_PCM_SUBFMTBIT(MSBITS_20) +#define SNDRV_PCM_SUBFMTBIT_MSBITS_24 _SNDRV_PCM_SUBFMTBIT(MSBITS_24) + struct snd_pcm_file { struct snd_pcm_substream *substream; int no_compat_mmap; |