ALSA: pcm: add new DSD sampleformat for native DSD playback on XMOS based devices

XMOS based USB DACs with native DSD support expose this feature via a USB
alternate setting. The audio format is either 32-bit raw or a 32-bit PCM format.
To utilize this feature on linux this patch introduces a new 32-bit DSD
sampleformat DSD_U32_LE.
A follow up patch will add a quirk for XMOS based devices to utilize the new format.
Further patches will add support to alsa-lib.

Signed-off-by: Jurgen Kramer <gtmkramer@xs4all.nl>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Jurgen Kramer 2014-09-05 10:47:56 +02:00 committed by Takashi Iwai
parent 7fd4394dfe
commit d4288d3fac
4 changed files with 8 additions and 1 deletions

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@ -183,6 +183,7 @@ struct snd_pcm_ops {
#define SNDRV_PCM_FMTBIT_G723_40_1B _SNDRV_PCM_FMTBIT(G723_40_1B)
#define SNDRV_PCM_FMTBIT_DSD_U8 _SNDRV_PCM_FMTBIT(DSD_U8)
#define SNDRV_PCM_FMTBIT_DSD_U16_LE _SNDRV_PCM_FMTBIT(DSD_U16_LE)
#define SNDRV_PCM_FMTBIT_DSD_U32_LE _SNDRV_PCM_FMTBIT(DSD_U32_LE)
#ifdef SNDRV_LITTLE_ENDIAN
#define SNDRV_PCM_FMTBIT_S16 SNDRV_PCM_FMTBIT_S16_LE

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@ -219,7 +219,8 @@ typedef int __bitwise snd_pcm_format_t;
#define SNDRV_PCM_FORMAT_G723_40_1B ((__force snd_pcm_format_t) 47) /* 1 sample in 1 byte */
#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
#define SNDRV_PCM_FORMAT_DSD_U32_LE ((__force snd_pcm_format_t) 50) /* DSD, 4-byte samples DSD (x32), little endian */
#define SNDRV_PCM_FORMAT_LAST SNDRV_PCM_FORMAT_DSD_U32_LE
#ifdef SNDRV_LITTLE_ENDIAN
#define SNDRV_PCM_FORMAT_S16 SNDRV_PCM_FORMAT_S16_LE

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@ -215,6 +215,7 @@ static char *snd_pcm_format_names[] = {
FORMAT(G723_40_1B),
FORMAT(DSD_U8),
FORMAT(DSD_U16_LE),
FORMAT(DSD_U32_LE),
};
const char *snd_pcm_format_name(snd_pcm_format_t format)

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@ -148,6 +148,10 @@ static struct pcm_format_data pcm_formats[(INT)SNDRV_PCM_FORMAT_LAST+1] = {
.width = 16, .phys = 16, .le = 1, .signd = 0,
.silence = {},
},
[SNDRV_PCM_FORMAT_DSD_U32_LE] = {
.width = 32, .phys = 32, .le = 1, .signd = 0,
.silence = { 0x69, 0x69, 0x69, 0x69 },
},
/* FIXME: the following three formats are not defined properly yet */
[SNDRV_PCM_FORMAT_MPEG] = {
.le = -1, .signd = -1,