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 /sound/core/pcm.c | |
| 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 'sound/core/pcm.c')
| -rw-r--r-- | sound/core/pcm.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/sound/core/pcm.c b/sound/core/pcm.c index 20bb2d7c8d4b..c4bc15f048b6 100644 --- a/sound/core/pcm.c +++ b/sound/core/pcm.c @@ -265,6 +265,9 @@ static const char * const snd_pcm_access_names[] = { static const char * const snd_pcm_subformat_names[] = { SUBFORMAT(STD), + SUBFORMAT(MSBITS_MAX), + SUBFORMAT(MSBITS_20), + SUBFORMAT(MSBITS_24), }; static const char * const snd_pcm_tstamp_mode_names[] = { |