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| author | Daniel Mack <zonque@gmail.com> | 2013-04-17 00:01:36 +0800 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2013-04-18 10:02:33 +0200 |
| commit | ef7a4f979bd8201324b2bcd30277c14aba889f50 (patch) | |
| tree | 7235f0aa55aca6d7e7f2d67210c640e9ff4b9ec4 /include/uapi | |
| parent | d5657ec9f4ad048873f2682d8945905b29938f57 (diff) | |
| download | blackbird-obmc-linux-ef7a4f979bd8201324b2bcd30277c14aba889f50.tar.gz blackbird-obmc-linux-ef7a4f979bd8201324b2bcd30277c14aba889f50.zip | |
ALSA: add DSD formats
This patch adds two formats for Direct Stream Digital (DSD), a
pulse-density encoding format which is described here:
https://en.wikipedia.org/wiki/Direct_Stream_Digital
DSD operates on 2.8, 5.6 or 11.2MHz sample rates and as a 1-bit
stream.
The two new types added by this patch describe streams that are capable
of handling DSD samples in DOP format as 8-bit or in 16-bit (or at a x8
or x16 data rate, respectively).
DSD itself specifies samples in *bit*, while DOP and ALSA handle them
as *bytes*. Hence, a factor of 8 or 16 has to be applied for the sample
rare configuration, according to the following table:
configured hardware
176.4KHz 352.8kHz 705.6KHz <---- sample rate
8-bit 2.8MHz 5.6MHz
16-bit 2.8Mhz 5.6MHz 11.2MHz
`-----------------------------'
actual DSD sample rates
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'include/uapi')
| -rw-r--r-- | include/uapi/sound/asound.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/include/uapi/sound/asound.h b/include/uapi/sound/asound.h index 1774a5c3ef10..e3983d508272 100644 --- a/include/uapi/sound/asound.h +++ b/include/uapi/sound/asound.h @@ -214,7 +214,9 @@ typedef int __bitwise snd_pcm_format_t; #define SNDRV_PCM_FORMAT_G723_24_1B ((__force snd_pcm_format_t) 45) /* 1 sample in 1 byte */ #define SNDRV_PCM_FORMAT_G723_40 ((__force snd_pcm_format_t) 46) /* 8 Samples in 5 bytes */ #define SNDRV_PCM_FORMAT_G723_40_1B ((__force snd_pcm_format_t) 47) /* 1 sample in 1 byte */ -#define SNDRV_PCM_FORMAT_LAST SNDRV_PCM_FORMAT_G723_40_1B +#define SNDRV_PCM_FORMAT_DSD_U8 ((__force snd_pcm_format_t) 48) /* DSD, 1-byte samples DSD (x8) */ +#define SNDRV_PCM_FORMAT_DSD_U16_LE ((__force snd_pcm_format_t) 49) /* DSD, 2-byte samples DSD (x16), little endian */ +#define SNDRV_PCM_FORMAT_LAST SNDRV_PCM_FORMAT_DSD_U16_LE #ifdef SNDRV_LITTLE_ENDIAN #define SNDRV_PCM_FORMAT_S16 SNDRV_PCM_FORMAT_S16_LE |
